96 results on '"Jason, Ho"'
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2. Frameless versus frame-based stereotactic radiosurgery for intracranial arteriovenous malformations: A propensity-matched analysis
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Zhexi He, Man Kit Jason Ho, Wan Yan Venus Lee, Hing Yuen Law, Yee Wa Victy Wong, To-wai Leung, Wing Ho Mui, Sui-To Wong, Chi Sing Frank Wong, and Kwong Yui Yam
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Adverse radiation effect ,Frameless radiosurgery ,Intracranial arteriovenous malformations ,Obliteration rate ,Linear accelerator ,Mask-based radiosurgery ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Objective: The frameless linear accelerator (LINAC) based stereotactic radiosurgery (SRS) has been evolving with a reduction in patient discomfort. However, there was limited evidence comparing frame-based and frameless SRS for intracranial arteriovenous malformations (AVM). We aimed to compare the treatment outcomes between frame-based and frameless LINAC SRS. Materials and Methods: This retrospective cohort compared the outcomes of frame-based LINAC SRS (1998–2009) with frameless LINAC SRS (2010–2020). The primary outcome was the obliteration rate. The other outcomes included the neurological, radiological, and functional outcomes after SRS. A matched cohort was identified by propensity scores for further comparisons. Results: A total of 65 patients were included with a mean follow-up time of 13.2 years (158.5 months). There were 40 patients in the frame-based group and 25 patients in the frameless group. The overall obliteration rate was comparable (Frame-based 82.5% vs Frameless 80.0%, p = 0.310) and not significantly different over time (log-rank p = 0.536). The crude post-SRS hemorrhage rate was 1.5% and the incidence was 0.3 per 100 person-years. There were 67.7% of patients with AVM obliteration without new persistent neurological deficits at the last visit and 56.9% of patients with AVM obliteration without any deficits (transient or persistent) during the entire follow-up period. Four patients (8.0%) developed late onset persistent adverse radiation effects (more than 96 months after SRS) among 50 patients with more than 8-year surveillance. In the propensity-matched cohort of 42 patients, there was no significant difference in AVM obliteration (Frame-based vs Frameless, log-rank p = 0.984). Conclusion: Frameless and frame-based LINAC SRS have comparable efficacy in intracranial AVM obliteration. A longer follow-up duration may further characterize the rate of late adverse radiation effects in frameless SRS.
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- 2023
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3. INBRX-120, a CD8α-targeted detuned IL-2 that selectively expands and activates tumoricidal effector cells for safe and durable in vivo responses
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Jason Ho, Chelsie Macedo, Garrett Cyprus, Rajay Pandit, Anya Polovina, Nadja Kern, Abrahim Hussain, Sae Jeong Ahn, William Crago, Emily Rowell, Florian J Sulzmaier, John C Timmer, and Brendan P Eckelman
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background As a major driver of lymphocyte proliferation and activation interleukin 2 (IL-2) is a crucial mediator for antitumor responses. Despite promising activity in a subset of patients, wider therapeutic utility of IL-2 (aldesleukin) has been hampered by severe dose-limiting toxicities, the expansion of immunosuppressive regulatory T cells and a poor pharmacokinetic (PK) profile. Recent engineering efforts, including non-α IL-2 variants, have lowered the toxicity profile, but have yet to induce meaningful antitumor activity in a wider patient population.Methods We engineered INBRX-120, a CD8α-targeted Cisleukin™ molecule consisting of an affinity tuned IL-2 (IL2-x) connected to two high affinity CD8α-specific single domain antibodies via an effector-silenced Fc domain. To show that this large affinity differential enables directed IL-2 cis-signaling exclusively on CD8α-expressing tumoricidal effector cell populations, INBRX-120 effects on target cell expansion, activation and antitumor activity were tested in vitro. In vivo antitumor efficacy was evaluated in syngeneic mouse models alone or in combination with programmed cell death protein-1 (PD-1) blockade. Preclinical safety, as well as pharmacodynamic (PD) and PK profiling was carried out in non-human primates.Results INBRX-120 effectively expanded and enhanced the cytotoxic capacity of CD8 T cells and natural killer cells towards tumor cells without affecting regulatory T cells in vitro and in vivo. In syngeneic mouse models, INBRX-120 surrogate showed safe, potent, and durable antitumor efficacy alone and in combination with PD-1 blockade. In non-human primates, INBRX-120 expanded and activated CD8α-expressing effector cells, showed a favorable PK profile, and was well tolerated up to a dose of 1 mg/kg.Conclusions Through its unique cis-signaling activity on CD8α-expressing effector cells, INBRX-120 overcomes the major limitations of IL-2-based therapy and effectively harnesses IL-2’s potent intrinsic antitumor activity. This novel therapeutic strategy promises safer clinical activity that could induce meaningful antitumor efficacy in a wider set of patients with various cancer indications.
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- 2023
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4. Gang Up with the Right Gangs – A Comparative Study on the Law of Unlawful Assembly in Hong Kong and Japan
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Jason Ho Ching Cheung
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hong kong ,japan ,unlawful assembly ,riot ,public order ordinance ,freedom of assembly ,disturbance ,Political science (General) ,JA1-92 ,Economics as a science ,HB71-74 - Abstract
Freedom of assembly is guaranteed in most if not all democracies, but it is not without limit and regulation under their public order laws. Hong Kong and Japan are two democratic regimes in East Asia with sound rule of law despite few studies have been conducted to compare the public order offences of the two jurisdictions. By studying the law of unlawful assembly and law of disturbance in Hong Kong and Japan respectively, this article aims at discovering the similarities and differences in criminalizing assemblies in the two jurisdictions. Issues on comparation of Hong Kong and Japanese public order offences, significance of the law of unlawful assemblies, and possible justification of differences in Hong Kong and Japanese jurisdiction on unlawful assembly will be discussed. This article further raises the concern of the law enforcement on unlawful assembly and its relationship with the severity of the offence itself. A conclusion is drawn that Japan might have a wider coverage of conduct constituting unlawful assembly but the recent social and political movement in Hong Kong may have significant influence on the deterring effect imposed by the latter’s jurisprudence.
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- 2021
5. Room temperature synthesis of nanocomposite thin films with embedded Cs2AgIn0.9Bi0.1Cl6 lead-free double perovskite nanocrystals with long-term water stability, wide range pH tolerance, and high quantum yield
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Bayer, Steevanson, primary, Yu, Jason Ho Yin, additional, and Nagl, Stefan, additional
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- 2024
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6. Room temperature synthesis of nanocomposite thin films with embedded Cs2AgIn0.9Bi0.1Cl6 leadfree double perovskite nanocrystals with long-term water stability, wide range pH tolerance, and high quantum yield.
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Bayer, Steevanson, Jason Ho Yin Yu, and Nagl, Stefan
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- 2024
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7. Bifunctional molecules targeting SARS-CoV-2 spike and the polymeric Ig receptor display neutralization activity and mucosal enrichment
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Ian White, Ninkka Tamot, Rajitha Doddareddy, Jason Ho, Qun Jiao, Paul B. Harvilla, Tong-Yuan Yang, Brian Geist, M. Jack Borrok, Matthew D. Truppo, Rajkumar Ganesan, Partha Chowdhury, and Adam Zwolak
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Polymeric Ig receptor ,pIgR ,sars-cov-2. coronavirus ,antibody ,Igg ,bifunctional ,Therapeutics. Pharmacology ,RM1-950 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The global health crisis and economic tolls of COVID-19 necessitate a panoply of strategies to treat SARS-CoV-2 infection. To date, few treatment options exist, although neutralizing antibodies against the spike glycoprotein have proven to be effective. Because infection is initiated at the mucosa and propagates mainly at this site throughout the course of the disease, blocking the virus at the mucosal milieu should be effective. However, administration of biologics to the mucosa presents a substantial challenge. Here, we describe bifunctional molecules combining single-domain variable regions that bind to the polymeric Ig receptor (pIgR) and to the SARS-CoV-2 spike protein via addition of the ACE2 extracellular domain (ECD). The hypothesis behind this design is that pIgR will transport the molecule from the circulation to the mucosal surface where the ACE ECD would act as a decoy receptor for the nCoV2. The bifunctional molecules bind SARS-Cov-2 spike glycoprotein in vitro and efficiently transcytose across the lung epithelium in human tissue-based analyses. Designs featuring ACE2 tethered to the C-terminus of the Fc do not induce antibody-dependent cytotoxicity against pIgR-expressing cells. These molecules thus represent a potential therapeutic modality for systemic administration of neutralizing anti-SARS-CoV-2 molecules to the mucosa.
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- 2021
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8. Zebrafish Paralogs brd2a and brd2b Are Needed for Proper Circulatory, Excretory and Central Nervous System Formation and Act as Genetic Antagonists during Development
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Gregory L. Branigan, Kelly S. Olsen, Isabella Burda, Matthew W. Haemmerle, Jason Ho, Alexandra Venuto, Nicholas D. D’Antonio, Ian E. Briggs, and Angela J. DiBenedetto
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gene duplication ,functional antagonism ,gene interaction ,pronephros ,peripheral blood island ,spinal interneuron ,Biology (General) ,QH301-705.5 - Abstract
Brd2 belongs to the BET family of epigenetic transcriptional co-regulators that act as adaptor-scaffolds for the assembly of chromatin-modifying complexes and other factors at target gene promoters. Brd2 is a protooncogene and candidate gene for juvenile myoclonic epilepsy in humans, a homeobox gene regulator in Drosophila, and a maternal-zygotic factor and cell death modulator that is necessary for normal development of the vertebrate central nervous system (CNS). As two copies of Brd2 exist in zebrafish, we use antisense morpholino knockdown to probe the role of paralog Brd2b, as a comparative study to Brd2a, the ortholog of human Brd2. A deficiency in either paralog results in excess cell death and dysmorphology of the CNS, whereas only Brd2b deficiency leads to loss of circulation and occlusion of the pronephric duct. Co-knockdown of both paralogs suppresses single morphant defects, while co-injection of morpholinos with paralogous RNA enhances them, suggesting novel genetic interaction with functional antagonism. Brd2 diversification includes paralog-specific RNA variants, a distinct localization of maternal factors, and shared and unique spatiotemporal expression, providing unique insight into the evolution and potential functions of this gene.
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- 2021
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9. Figure S3 from Selective Tumor Cell Apoptosis and Tumor Regression in CDH17-Positive Colorectal Cancer Models using BI 905711, a Novel Liver-Sparing TRAILR2 Agonist
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Klaus Peter Kuenkele, Mark Pearson, Norbert Kraut, Frank Hilberg, Iñigo Tirapu, Maria Antonietta Impagnatiello, Craig Giragossian, Joerg Rinnenthal, Rachel Kroe-Barrett, Philip N. Gorman, Darrin Dutcher, Jason Ho, Catarina Pinto, Paolo Chetta, Andreas Wernitznig, Cordula Weishaeupl, Shirley Wang, and Juan Manuel García-Martínez
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CDH17 and TRAILR2 protein expression and their correlation with BI 905711 minPOC in CRC cell lines.
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- 2023
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10. Supplementary Table 1-2 from Effects of Anti-VEGF on Pharmacokinetics, Biodistribution, and Tumor Penetration of Trastuzumab in a Preclinical Breast Cancer Model
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C. Andrew Boswell, Leslie A. Khawli, Paul J. Fielder, Frank-Peter Theil, Jay Tibbitts, Mark Sliwkowski, Daniela Bumbaca, Peter Nauka, Nicholas Lewin-Koh, Katherine R. Kozak, Josefa dela Cruz Chuh, Sheila Bheddah, Nicholas Majidy, Marjie Van Hoy, Gary Cain, Kathryn Parsons-Reponte, Eric Cheng, Sarajane Ross, Suzanna Clark, Sheila Ulufatu, Jason Ho, Tapan K. Nayak, Simon P. Williams, Eduardo E. Mundo, and Cinthia V. Pastuskovas
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PDF file - 87K
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- 2023
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11. Supplementary Data from Effect of Modulating FcRn Binding on Direct and Pretargeted Tumor Uptake of Full-length Antibodies
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C. Andrew Boswell, Jack D. Sadowsky, James Ernst, Shang-Fan Yu, Jeffrey Lau, Jason Ho, Sheila Ulufatu, Christopher W. Davies, James T. Koerber, Gregory Z. Ferl, Danielle Mandikian, Hanine Rafidi, and Lidia Nazarova
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Supplementary methods (S1-S4), Supplementary tables (1-4) and Supplementary Figures (1-5)
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- 2023
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12. Data from Relative Target Affinities of T-Cell–Dependent Bispecific Antibodies Determine Biodistribution in a Solid Tumor Mouse Model
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C. Andrew Boswell, Teemu T. Junttila, Saileta Prabhu, Mark S. Dennis, Sean B. Joseph, Kedan Lin, Klara Totpal, Robyn Clark, Maria Hristopoulos, Jason Ho, Dionysos Slaga, Jeffrey Eastham-Anderson, Ji Li, Amy A. Lo, Nene Takahashi, and Danielle Mandikian
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Anti-HER2/CD3, a T-cell–dependent bispecific antibody (TDB) construct, induces T-cell–mediated cell death in cancer cells expressing HER2 by cross-linking tumor HER2 with CD3 on cytotoxic T cells, thereby creating a functional cytolytic synapse. TDB design is a very challenging process that requires consideration of multiple parameters. Although therapeutic antibody design strategy is commonly driven by striving for the highest attainable antigen-binding affinity, little is known about how the affinity of each TDB arm can affect the targeting ability of the other arm and the consequent distribution and efficacy. To our knowledge, no distribution studies have been published using preclinical models wherein the T-cell–targeting arm of the TDB is actively bound to T cells. We used a combined approach involving radiochemistry, invasive biodistribution, and noninvasive single-photon emission tomographic (SPECT) imaging to measure TDB distribution and catabolism in transgenic mice with human CD3ϵ expression on T cells. Using CD3 affinity variants, we assessed the impact of CD3 affinity on short-term pharmacokinetics, tissue distribution, and cellular uptake. Our experimental approach determined the relative effects of (i) CD3 targeting to normal tissues, (ii) HER2 targeting to HER2-expressing tumors, and (iii) relative HER2/CD3 affinity, all as critical drivers for TDB distribution. We observed a strong correlation between CD3 affinity and distribution to T-cell–rich tissues, with higher CD3 affinity reducing systemic exposure and shifting TDB distribution away from tumor to T-cell–containing tissues. These observations have important implications for clinical translation of bispecific antibodies for cancer immunotherapy. Mol Cancer Ther; 17(4); 776–85. ©2018 AACR.
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- 2023
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13. Supplementary Material and Methods from Selective Tumor Cell Apoptosis and Tumor Regression in CDH17-Positive Colorectal Cancer Models using BI 905711, a Novel Liver-Sparing TRAILR2 Agonist
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Klaus Peter Kuenkele, Mark Pearson, Norbert Kraut, Frank Hilberg, Iñigo Tirapu, Maria Antonietta Impagnatiello, Craig Giragossian, Joerg Rinnenthal, Rachel Kroe-Barrett, Philip N. Gorman, Darrin Dutcher, Jason Ho, Catarina Pinto, Paolo Chetta, Andreas Wernitznig, Cordula Weishaeupl, Shirley Wang, and Juan Manuel García-Martínez
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Supplementary Material and Methods
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- 2023
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14. Supplementary Data from Valency of HER2 Targeting Antibodies Influences Tumor Cell Internalization and Penetration
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C. Andrew Boswell, Gregory Z. Ferl, Amrita V. Kamath, Shang-Fan Yu, Mary Ann T. Go, Christoph Spiess, T. Noelle Lombana, Sheila Ulufatu, Jason Ho, Alecia T. Dent, Anna King, Lauren N. Sermeño, Danielle Mandikian, and Madeleine K. Ramos
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Supplementary Data and Methods
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- 2023
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15. Table S1, S2, S3 and S4 from Selective Tumor Cell Apoptosis and Tumor Regression in CDH17-Positive Colorectal Cancer Models using BI 905711, a Novel Liver-Sparing TRAILR2 Agonist
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Klaus Peter Kuenkele, Mark Pearson, Norbert Kraut, Frank Hilberg, Iñigo Tirapu, Maria Antonietta Impagnatiello, Craig Giragossian, Joerg Rinnenthal, Rachel Kroe-Barrett, Philip N. Gorman, Darrin Dutcher, Jason Ho, Catarina Pinto, Paolo Chetta, Andreas Wernitznig, Cordula Weishaeupl, Shirley Wang, and Juan Manuel García-Martínez
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S1: Evaluation of CDH17 and TRAILR2 IHC staining in hepatic metastases of colorectal cancer -S2:BI 905711 kinetic and steady-state measurements -S3: CDH17 and TRAILR2 mean fluorescence intensity, antibody binding capacity and BI 905711 / TAS266' minPOC in 24 CRC cell lines -S4: Intergroup comparison of gross pathology observations in Cynomolgus Monkey small intestine, large intestine and pancreas
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- 2023
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16. Data from Selective Tumor Cell Apoptosis and Tumor Regression in CDH17-Positive Colorectal Cancer Models using BI 905711, a Novel Liver-Sparing TRAILR2 Agonist
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Klaus Peter Kuenkele, Mark Pearson, Norbert Kraut, Frank Hilberg, Iñigo Tirapu, Maria Antonietta Impagnatiello, Craig Giragossian, Joerg Rinnenthal, Rachel Kroe-Barrett, Philip N. Gorman, Darrin Dutcher, Jason Ho, Catarina Pinto, Paolo Chetta, Andreas Wernitznig, Cordula Weishaeupl, Shirley Wang, and Juan Manuel García-Martínez
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Activation of TRAILR2 has emerged as an important therapeutic concept in cancer treatment. TRAILR2 agonistic molecules have only had limited clinical success, to date, due either to lack of efficacy or hepatotoxicity. BI 905711 is a novel tetravalent bispecific antibody targeting both TRAILR2 and CDH17 and represents a novel liver-sparing TRAILR2 agonist specifically designed to overcome the disadvantages of previous strategies. Here, we show that BI 905711 effectively triggered apoptosis in a broad panel of CDH17-positive colorectal cancer tumor cells in vitro. Efficient induction of apoptosis was dependent on the presence of CDH17, as exemplified by the greater than 1,000-fold drop in potency in CDH17-negative cells. BI 905711 demonstrated single-agent tumor regressions in CDH17-positive colorectal cancer xenografts, an effect that was further enhanced upon combination with irinotecan. Antitumor efficacy correlated with induction of caspase activation, as measured in both the tumor and plasma. Effective tumor growth inhibition was further demonstrated across a series of different colorectal cancer PDX models. BI 905711 induced apoptosis in both a cis (same cell) as well as trans (adjacent cell) fashion, translating into significant antitumor activity even in xenograft models with heterogeneous CDH17 expression. In summary, we demonstrate that BI 905711 has potent and selective antitumor activity in CDH17-positive colorectal cancer models both in vitro and in vivo. The high prevalence of over 95% CDH17-positive tumors in patients with colorectal cancer, the molecule preclinical efficacy together with its potential for a favorable safety profile, support the ongoing BI 905711 phase I trial in colorectal cancer and additional CDH17-positive cancer types (NCT04137289).
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- 2023
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17. Supplemental Methods and Figures 1-5 from Relative Target Affinities of T-Cell–Dependent Bispecific Antibodies Determine Biodistribution in a Solid Tumor Mouse Model
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C. Andrew Boswell, Teemu T. Junttila, Saileta Prabhu, Mark S. Dennis, Sean B. Joseph, Kedan Lin, Klara Totpal, Robyn Clark, Maria Hristopoulos, Jason Ho, Dionysos Slaga, Jeffrey Eastham-Anderson, Ji Li, Amy A. Lo, Nene Takahashi, and Danielle Mandikian
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Supplemental Methods, followed by Supplemental Figures S1, S2, S3, S4 and S5. Supplementary Fig. S1 In vitro binding of TDBs to HER2 and CD3 expressing cell lines. Supplementary Fig. S2 HER2 expression in model cell lines in vitro and tumors in vivo. Supplementary Fig. S3 HER2, CD3� and MECA-32 staining and vascular characterization of HER2 positive and negative tumors. Supplementary Fig. S4 T cell infiltration and CD3 expression in murine CT26 and CT26-HER2 tumors. Supplementary Fig. S5 Pharmacokinetic data from whole blood and cell pellet fractions
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- 2023
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18. Supplementary Figure 1 from Effects of Anti-VEGF on Pharmacokinetics, Biodistribution, and Tumor Penetration of Trastuzumab in a Preclinical Breast Cancer Model
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C. Andrew Boswell, Leslie A. Khawli, Paul J. Fielder, Frank-Peter Theil, Jay Tibbitts, Mark Sliwkowski, Daniela Bumbaca, Peter Nauka, Nicholas Lewin-Koh, Katherine R. Kozak, Josefa dela Cruz Chuh, Sheila Bheddah, Nicholas Majidy, Marjie Van Hoy, Gary Cain, Kathryn Parsons-Reponte, Eric Cheng, Sarajane Ross, Suzanna Clark, Sheila Ulufatu, Jason Ho, Tapan K. Nayak, Simon P. Williams, Eduardo E. Mundo, and Cinthia V. Pastuskovas
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PDF file - 93K
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- 2023
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19. Data from Valency of HER2 Targeting Antibodies Influences Tumor Cell Internalization and Penetration
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C. Andrew Boswell, Gregory Z. Ferl, Amrita V. Kamath, Shang-Fan Yu, Mary Ann T. Go, Christoph Spiess, T. Noelle Lombana, Sheila Ulufatu, Jason Ho, Alecia T. Dent, Anna King, Lauren N. Sermeño, Danielle Mandikian, and Madeleine K. Ramos
- Abstract
T-cell–dependent bispecific antibodies (TDB) have been a major advancement in the treatment of cancer, allowing for improved targeting and efficacy for large molecule therapeutics. TDBs are comprised of one arm targeting a surface antigen on a cancer cell and another targeting an engaging surface antigen on a cytotoxic T cell. To impart this function, the antibody must be in a bispecific format as opposed to the more conventional bivalent format. Through in vitro and in vivo studies, we sought to determine the impact of changing antibody valency on solid tumor distribution and catabolism. A bivalent anti-HER2 antibody exhibited higher catabolism than its full-length monovalent binding counterpart in vivo by both invasive tissue harvesting and noninvasive single photon emission computed tomography/X-ray computed tomography imaging despite similar systemic exposures for the two molecules. To determine what molecular factors drove in vivo distribution and uptake, we developed a mechanistic model for binding and catabolism of monovalent and bivalent HER2 antibodies in KPL4 cells. This model suggests that observed differences in cellular uptake of monovalent and bivalent antibodies are caused by the change in apparent affinity conferred by avidity as well as differences in internalization and degradation rates of receptor bound antibodies. To our knowledge, this is the first study to directly compare the targeting abilities of monovalent and bivalent full-length antibodies. These findings may inform diverse antibody therapeutic modalities, including T-cell–redirecting therapies and drug delivery strategies relying upon receptor internalization.
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- 2023
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20. Intravitreal ocriplasmin for the treatment of vitreomacular traction and macular hole- A study of efficacy and safety based on NICE guidance.
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Mahiul M K Muqit, Robin Hamilton, Jason Ho, Sally Tucker, and Helen Buck
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Medicine ,Science - Abstract
To evaluate the real world clinical outcomes of intravitreal ocriplasmin in patients with vitreomacular traction (VMT) with and without full thickness macular holes (FTMH) treated according to NICE guidance.Retrospective observational case series of 25 patients treated with a single intravitreal ocriplasmin injection between December 2013 and December 2015. Best corrected visual acuity and optical coherence tomography exams were performed to determine visual outcomes and anatomical VMT release and FTMH closure over time. Two patient groups were identified: ocular macular co-morbidity (OCM) and no OCM (nOCM), with follow-up at 4, 12, and 24 weeks.Twenty-five patients were identified that included 19 patients with VMT, and 6 patients with VMT plus FTMH. In the nOCM group of 22 patients, the release rate of VMT was 44%, 63%, and 69% at 4, 12 and 24 weeks respectively. In the "real-world" OCM group of 25 patients, the VMT release rate was 37%, 53%, and 58% at the same time-points. In both groups, the FTMH closure rate was 33%, 50%, and 67% at 4, 12, and 24 weeks. At mean follow-up of 30 weeks in the VMT group with nOCM, the mean LogMAR VA improved significantly from 0.44 to 0.28 (p = 0.0068, paired t-test). Three were no serious adverse events.This study reports improved efficacy of intravitreal ocriplasmin for both VMT and FTMH, and is more favourable in patients with no ocular co-morbidity. We highlight the importance of careful patient selection and structured standard of care pathways to identify patients who will benefit from the positive visual and anatomical effects of intravitreal ocriplasmin.
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- 2018
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21. NEK10 tyrosine phosphorylates p53 and controls its transcriptional activity
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Jason Ho, Luis Palomero, Miquel Angel Pujana, Michael B. Yaffe, Nasir Haider, Vuk Stambolic, Bert van de Kooij, and Previn Dutt
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0301 basic medicine ,Regulation of gene expression ,Cancer Research ,Cell signaling ,Mutation ,Kinase ,DNA damage ,Tyrosine phosphorylation ,Biology ,medicine.disease_cause ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,chemistry ,030220 oncology & carcinogenesis ,Genetics ,medicine ,Phosphorylation ,Carcinogenesis ,Molecular Biology - Abstract
In response to genotoxic stress, multiple kinase signaling cascades are activated, many of them directed towards the tumor suppressor p53, which coordinates the DNA damage response (DDR). Defects in DDR pathways lead to an accumulation of mutations that can promote tumorigenesis. Emerging evidence implicates multiple members of the NimA-related kinase (NEK) family (NEK1, NEK10, and NEK11) in the DDR. Here, we describe a function for NEK10 in the regulation of p53 transcriptional activity through tyrosine phosphorylation. NEK10 loss increases cellular proliferation by modulating the p53-dependent transcriptional output. NEK10 directly phosphorylates p53 on Y327, revealing NEK10’s unexpected substrate specificity. A p53 mutant at this site (Y327F) acts as a hypomorph, causing an attenuated p53-mediated transcriptional response. Consistently, NEK10-deficient cells display heightened sensitivity to DNA-damaging agents. Further, a combinatorial score of NEK10 and TP53-target gene expression is an independent predictor of a favorable outcome in breast cancers.
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- 2020
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22. Enhanced delivery of antibodies across the blood-brain barrier via TEMs with inherent receptor-mediated phagocytosis
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Suzanne Edavettal, Pilar Cejudo-Martin, Bidisha Dasgupta, Danlin Yang, Matthew D. Buschman, Derrick Domingo, Kristof Van Kolen, Pharavee Jaiprasat, Renata Gordon, Keith Schutsky, Brian Geist, Natalie Taylor, Camille Helene Soubrane, Elisabeth Van Der Helm, Ann LaCombe, Zemeda Ainekulu, Eilyn Lacy, Jason Aligo, Jason Ho, Yingbo He, Peter F. Lebowitz, James T. Patterson, Justin M. Scheer, and Sanjaya Singh
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Blood-Brain Barrier ,Receptors, Transferrin ,Biological Transport ,General Medicine ,Transcytosis ,Antibodies - Abstract
The near impermeability of the blood-brain barrier (BBB) and the unique neuroimmune environment of the CNS prevents the effective use of antibodies in neurological diseases. Delivery of biotherapeutics to the brain can be enabled through receptor-mediated transcytosis via proteins such as the transferrin receptor, although limitations such as the ability to use Fc-mediated effector function to clear pathogenic targets can introduce safety liabilities. Hence, novel delivery approaches with alternative clearance mechanisms are warranted.Binders that optimized transport across the BBB, known as transcytosis-enabling modules (TEMs), were identified using a combination of antibody discovery techniques and pharmacokinetic analyses. Functional activity of TEMs were subsequently evaluated by imaging for the ability of myeloid cells to phagocytose target proteins and cells.We demonstrated significantly enhanced brain exposure of therapeutic antibodies using optimal transferrin receptor or CD98 TEMs. We found that these modules also mediated efficient clearance of tau aggregates and HER2+ tumor cells via a non-classical phagocytosis mechanism through direct engagement of myeloid cells. This mode of clearance potentially avoids the known drawbacks of FcγR-mediated antibody mechanisms in the brain such as the neurotoxic release of proinflammatory cytokines and immune cell exhaustion.Our study reports a new brain delivery platform that harnesses receptor-mediated transcytosis to maximize brain uptake and uses a non-classical phagocytosis mechanism to efficiently clear pathologic proteins and cells. We believe these findings will transform therapeutic approaches to treat CNS diseases.This research was funded by Janssen, Pharmaceutical Companies of JohnsonJohnson.
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- 2021
23. Biodistribution and efficacy of an anti-TENB2 antibody-drug conjugate in a patient-derived model of prostate cancer
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Jennifer A. Lacap, Shang-Fan Yu, Eduardo E. Mundo, Leslie A. Khawli, Crystal Zhang, C. Andrew Boswell, Kedan Lin, Sheila Ulufatu, Daniela Bumbaca Yadav, Gregory Z. Ferl, Aimee Fourie-O'Donohue, Jason Ho, and Katherine R. Kozak
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0301 basic medicine ,Antibody-drug conjugate ,Biodistribution ,medicine.drug_class ,media_common.quotation_subject ,Pharmacology ,Monoclonal antibody ,antibody-drug conjugate ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Therapeutic index ,Pharmacokinetics ,medicine ,Internalization ,media_common ,biology ,business.industry ,imaging ,TENB2 ,prostate cancer ,medicine.disease ,body regions ,030104 developmental biology ,Oncology ,Proteoglycan ,030220 oncology & carcinogenesis ,biology.protein ,business ,pharmacokinetics ,Research Paper - Abstract
TENB2, a transmembrane proteoglycan protein, is a promising target for antibody drug conjugate (ADC) therapy due to overexpression in human prostate tumors and rapid internalization. We previously characterized how predosing with parental anti-TENB2 monoclonal antibody (mAb) at 1 mg/kg in a patient-derived LuCap77 explant model with high (3+) TENB2 expression could (i) block target-mediated intestinal uptake of tracer (& 0.1 mg/kg) levels of radiolabeled anti-TENB2-monomethyl auristatin E ADC while preserving tumor uptake, and (ii) maintain efficacy relative to ADC alone. Here, we systematically revisit this strategy to evaluate the effects of predosing on tumor uptake and efficacy in LuCap96.1, a low TENB2-expressing (1+) patient-derived model that is more responsive to ADC therapy than LuCap77. Importantly, rather than using tracer (& 0.1 mg/kg) levels, radiolabeled ADC tumor uptake was assessed at 1 mg/kg – one of the doses evaluated in the tumor growth inhibition study – in an effort to bridge tissue distribution (PK) with efficacy (PD). Predosing with mAb up to 1 mg/kg had no effect on efficacy. These findings warrant further investigations to determine whether predosing prior to ADC therapy might improve therapeutic index by preventing ADC disposition and possible toxicological liabilities in antigen-expressing healthy tissues.
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- 2019
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24. COVID-19 is Affecting the Presentation and Treatment of Melanoma Patients in the Northeastern United States
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Jason Ho, Catherine H. Davis, Stephanie H. Greco, Roberto J. Vidri, Jeffrey M. Farma, Vadim P. Koshenkov, and Adam C. Berger
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medicine.medical_specialty ,business.industry ,Colorectal cancer ,SARS-CoV-2 ,Melanoma ,Cancer ,COVID-19 ,Retrospective cohort study ,Disease ,medicine.disease ,Oncology ,Surgical oncology ,Internal medicine ,Pandemic ,Communicable Disease Control ,medicine ,Humans ,Surgery ,Stage (cooking) ,business ,Retrospective Studies - Abstract
Background Covid-19 significantly affected healthcare delivery over the past year, with a shift in focus away from nonurgent care. Emerging data are showing that screening for breast and colon cancer has dramatically decreased. It is unknown whether the same trend has affected patients with melanoma. Methods This is a retrospective cohort study of melanoma patients at two large-volume cancer centers. Patients were compared for 8 months before and after the lockdown. Outcomes focused on delay in treatment and possible resultant upstaging of melanoma. Results A total of 375 patients were treated pre-lockdown and 313 patients were treated post-lockdown (17% decrease). Fewer patients presented with in situ disease post-lockdown (15.3% vs. 17.9%), and a higher proportion presented with stage III-IV melanoma (11.2% vs. 9.9%). Comparing patients presenting 2 months before versus 2 months after the lockdown, there was an even more significant increase in Stage III-IV melanoma from 7.1% to 27.5% (p < 0.0001). Finally, in Stage IIIB-IIID patients, there was a decrease in patients receiving adjuvant therapy in the post lockdown period (20.0% vs. 15.2%). Conclusions As a result of the recent pandemic, it appears there has been a shift away from melanoma in situ and toward more advanced disease, which may have significant downstream effects on prognosis and could be due to a delay in screening. Significantly patients have presented after the lockdown, and fewer patients are undergoing the recommended adjuvant therapies. Patient outreach efforts are essential to ensure that patients continue to receive preventative medical care and screening as the pandemic continues.
- Published
- 2021
25. Should Routine Lymphoscintigraphy Be Standard of Care for Extremity Melanoma?
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Vadim P. Koshenkov, Jason Ho, Jeffrey S. Kempf, and Adam C. Berger
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medicine.medical_specialty ,Standard of care ,business.industry ,Melanoma ,Medicine ,Surgery ,Radiology ,business ,medicine.disease - Published
- 2021
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26. S467 Indications and Outcomes With Endoscopic Submucosal Dissection for High-Grade Barrett’s Esophagus
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Divya M. Chalikonda, Anthony Infantolino, Jason Ho, Alexander Schlachterman, Christina Tofani, and Adina Kazan
- Subjects
medicine.medical_specialty ,Hepatology ,business.industry ,Barrett's esophagus ,Gastroenterology ,medicine ,Endoscopic submucosal dissection ,business ,medicine.disease ,Surgery - Published
- 2021
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27. Valency of HER2 Targeting Antibodies Influences Tumor Cell Internalization and Penetration
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Mary Ann T. Go, Danielle Mandikian, Christoph Spiess, Lauren N. Sermeño, Gregory Z. Ferl, Madeleine K. Ramos, Shang-Fan Yu, T. Noelle Lombana, Sheila Ulufatu, Jason Ho, Alecia T. Dent, C. Andrew Boswell, Amrita V. Kamath, and Anna King
- Subjects
Cancer Research ,Receptor, ErbB-2 ,media_common.quotation_subject ,Antibody Affinity ,Apoptosis ,Breast Neoplasms ,Mice, SCID ,Mice ,Antigen ,In vivo ,Antibodies, Bispecific ,Tumor Cells, Cultured ,Cytotoxic T cell ,Animals ,Humans ,Avidity ,Tissue Distribution ,Internalization ,media_common ,Cell Proliferation ,biology ,Chemistry ,Xenograft Model Antitumor Assays ,Oncology ,Drug delivery ,Cancer cell ,Cancer research ,biology.protein ,Female ,Antibody ,T-Lymphocytes, Cytotoxic - Abstract
T-cell–dependent bispecific antibodies (TDB) have been a major advancement in the treatment of cancer, allowing for improved targeting and efficacy for large molecule therapeutics. TDBs are comprised of one arm targeting a surface antigen on a cancer cell and another targeting an engaging surface antigen on a cytotoxic T cell. To impart this function, the antibody must be in a bispecific format as opposed to the more conventional bivalent format. Through in vitro and in vivo studies, we sought to determine the impact of changing antibody valency on solid tumor distribution and catabolism. A bivalent anti-HER2 antibody exhibited higher catabolism than its full-length monovalent binding counterpart in vivo by both invasive tissue harvesting and noninvasive single photon emission computed tomography/X-ray computed tomography imaging despite similar systemic exposures for the two molecules. To determine what molecular factors drove in vivo distribution and uptake, we developed a mechanistic model for binding and catabolism of monovalent and bivalent HER2 antibodies in KPL4 cells. This model suggests that observed differences in cellular uptake of monovalent and bivalent antibodies are caused by the change in apparent affinity conferred by avidity as well as differences in internalization and degradation rates of receptor bound antibodies. To our knowledge, this is the first study to directly compare the targeting abilities of monovalent and bivalent full-length antibodies. These findings may inform diverse antibody therapeutic modalities, including T-cell–redirecting therapies and drug delivery strategies relying upon receptor internalization.
- Published
- 2020
28. The PTEN and ATM axis controls the G1/S cell cycle checkpoint and tumorigenesis in HER2-positive breast cancer
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Luke N. Buckler, Emily Cianci, Bryan E. Snow, Tak Wah Mak, Jason Ho, Vuk Stambolic, Chiara Gorrini, Jerome Fortin, Jillian Haight, Christian Bassi, Andrew Wakeham, and Annick You-Ten
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DNA damage ,Carcinogenesis ,Molecular biology ,Breast Neoplasms ,Mammary Neoplasms, Animal ,Genotoxic Stress ,Ataxia Telangiectasia Mutated Proteins ,medicine.disease_cause ,Article ,law.invention ,Mice ,law ,medicine ,PTEN ,Animals ,Humans ,Tumour-suppressor proteins ,Mutation ,biology ,Chemistry ,Tumor Suppressor Proteins ,Cell Cycle ,PTEN Phosphohydrolase ,Cell Biology ,Cell Cycle Checkpoints ,Apoptosis ,biology.protein ,Cancer research ,Suppressor ,Phosphorylation ,Female - Abstract
The tumor suppressor PTEN is disrupted in a large proportion of cancers, including in HER2-positive breast cancer, where its loss is associated with resistance to therapy. Upon genotoxic stress, ataxia telangiectasia mutated (ATM) is activated and phosphorylates PTEN on residue 398. To elucidate the physiological role of this molecular event, we generated and analyzed knock-in mice expressing a mutant form of PTEN that cannot be phosphorylated by ATM (PTEN-398A). This mutation accelerated tumorigenesis in a model of HER2-positive breast cancer. Mammary tumors in bi-transgenic mice carrying MMTV-neu and Pten398A were characterized by DNA damage accumulation but reduced apoptosis. Mechanistically, phosphorylation of PTEN at position 398 is essential for the proper activation of the S phase checkpoint controlled by the PI3K–p27Kip1–CDK2 axis. Moreover, we linked these defects to the impaired ability of the PTEN-398A protein to relocalize to the plasma membrane in response to genotoxic stress. Altogether, our results uncover a novel role for ATM-dependent PTEN phosphorylation in the control of genomic stability, cell cycle progression, and tumorigenesis.
- Published
- 2020
29. Abstract 3513: INBRX-121, a safe and efficacious molecular targeted cytokine that enhances NK cell-mediated tumor killing
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Heather Kinkead, Florian J. Sulzmaier, Anya Polovina, Nadja Kern, Angelica Sanabria, Jason Ho, Chelsie Macedo, Ryan Henderson, Abrahim Hussain, Rajay Pandit, William Crago, Emily Rowell, and Brendan P. Eckelman
- Subjects
Cancer Research ,Oncology - Abstract
IL-2 is a powerful cytokine that enhances the activity of and induces the expansion of tumoricidal effector cells including T and NK cells. Despite promising signs of activity, the clinical utility of IL-2 is limited due to severe treatment-associated toxicities including vascular leak syndrome and the concurrent expansion of immunosuppressive regulatory T cells, which blunts efficacy. We developed a molecular targeted cytokine (MTC) platform that combines an engineered IL-2 variant with reduced affinity for the IL-2 receptor and high affinity single-domain antibodies (sdAb) to restrict IL-2 receptor signaling to cells expressing the target antigen (termed cis-signaling). INBRX-121 is an MTC designed to deliver IL-2 to NK cells using an NKp46-specific sdAb as the targeting moiety. In vitro, INBRX-121 induces dose-dependent STAT5 phosphorylation and proliferation in NK cells with comparable potency to wild-type IL-2, while showing no NKp46-independent activity at concentrations of more than three magnitudes higher than that required for NK cell activity. INBRX-121 enhances NK cell activation and cytotoxic capacity, thereby reducing the NK-to-target cell ratio as well as the target receptor density needed for optimal tumor cell killing. Furthermore, INBRX-121 lowers the threshold for antibody-dependent cellular cytotoxicity (ADCC) and increases maximal target cell killing in combination with ADCC-competent antibodies to an extent that may lessen the need for Fc engineering to enhance binding to the low affinity CD16A variant. In vivo, INBRX-121 demonstrates potent anti-tumor activity with increased intra-tumoral NK cell accumulation and upregulation of NK cell activation markers. INBRX-121 monotherapy reduces primary tumor growth and the formation of metastasis, while combination with ADCC-competent antibodies further increases NK cell activity to convert tumor growth suppression into complete tumor elimination. INBRX-121 is well tolerated in rodents and non-human primates and no overt signs of toxicity have been observed in cynomolgus monkeys up to the highest administered dose of 30 mg/kg. Our MTC platform provides a novel path to overcoming the limitations of IL-2 therapy through the pinpointed delivery of IL-2 activity to target cells of interest. In the case of INBRX-121 this ensures potent enhancement of the naturally broad anti-tumor activity of NK cells, which have distinct advantages over T cell therapeutics. Unlike T cells, tumor recognition by NK cells is independent of MHC-presented antigens and can elicit immediate cytotoxic activity. Further, many of the toxicities associated with T cell therapeutics have not been observed with NK-centric treatments. INBRX-121 therefore provides a promising safe and efficacious treatment option for a broad array of cancer indications both as a monotherapy and in combination with ADCC-enabled antibodies. Citation Format: Heather Kinkead, Florian J. Sulzmaier, Anya Polovina, Nadja Kern, Angelica Sanabria, Jason Ho, Chelsie Macedo, Ryan Henderson, Abrahim Hussain, Rajay Pandit, William Crago, Emily Rowell, Brendan P. Eckelman. INBRX-121, a safe and efficacious molecular targeted cytokine that enhances NK cell-mediated tumor killing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3513.
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- 2022
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30. Site-specific conjugation allows modulation of click reaction stoichiometry for pretargeted SPECT imaging
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Gabriel Fung, Shang-Fan Yu, Cynthia McCaughey, Jason Ho, Lidia A. Nazarova, Saileta Prabhu, Hanine Rafidi, Danielle Mandikian, Priya Venkatraman, C. Andrew Boswell, Pragya Adhikari, Gregory Z. Ferl, Sheila Ulufatu, Isabel Figueroa, Jeffrey Lau, and Jack Sadowsky
- Subjects
Immunoconjugates ,Receptor, ErbB-2 ,medicine.drug_class ,medicine.medical_treatment ,pretargeted imaging ,Immunology ,010402 general chemistry ,Monoclonal antibody ,01 natural sciences ,Chemical kinetics ,Heterocyclic Compounds, 1-Ring ,Mice ,03 medical and health sciences ,Tetrazine ,chemistry.chemical_compound ,0302 clinical medicine ,Report ,Cell Line, Tumor ,Neoplasms ,Spect imaging ,medicine ,Animals ,Humans ,Immunology and Allergy ,Tissue Distribution ,Pretargeting ,Tomography, Emission-Computed, Single-Photon ,iEDDA reaction ,site-specific bioconjugation ,Antibodies, Monoclonal ,Radioimmunotherapy ,Xenograft Model Antitumor Assays ,0104 chemical sciences ,biorthogonal click chemistry ,chemistry ,SPECT ,Isotope Labeling ,030220 oncology & carcinogenesis ,Biophysics ,Click chemistry ,tetrazine ,Click Chemistry ,Molecular imaging - Abstract
Antibody pretargeting is a promising strategy for improving molecular imaging, wherein the separation in time of antibody targeting and radiolabeling can lead to rapid attainment of high contrast, potentially increased sensitivity, and reduced patient radiation exposure. The inverse electron demand Diels-Alder ‘click’ reaction between trans-cyclooctene (TCO) conjugated antibodies and radiolabeled tetrazines presents an ideal platform for pretargeted imaging due to rapid reaction kinetics, bioorthogonality, and potential for optimization of both slow and fast clearing components. Herein, we evaluated a series of anti-human epidermal growth factor receptor 2 (HER2) pretargeting antibodies containing distinct molar ratios of site-specifically incorporated TCO. The effect of stoichiometry on tissue distribution was assessed for pretargeting TCO-modified antibodies (monitored by 125I) and subsequent accumulation of an 111In-labeled tetrazine in a therapeutically relevant HER2+tumor-bearing mouse model. Single photon emission computed tomography (SPECT) imaging was also employed to assess tumor imaging at various TCO-to-monoclonal antibody (mAb) ratios. Increasing TCO-to-mAb molar ratios correlated with increased in vivo click reaction efficiency evident by increased tumor distribution and systemic exposure of 111In-labeled tetrazines. The pharmacokinetics of TCO-modified antibodies did not vary with stoichiometry. Pretargeted SPECT imaging of HER2-expressing tumors using 111In-labeled tetrazine demonstrated robust click reaction with circulating antibody at ~2 hours and good tumor delineation for both the 2 and 6 TCO-to-mAb ratio variants at 24 hours, consistent with a limited cell-surface pool of pretargeted antibody and benefit from further distribution and internalization. To our knowledge, this represents the first reported systematic analysis of how pretargeted imaging is affected solely by variation in click reaction stoichiometry through site-specific conjugation chemistry.
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- 2018
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31. ASO Visual Abstract: COVID-19 is Affecting the Presentation and Treatment of Melanoma Patients in the Northeastern United States
- Author
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Catherine H. Davis, Jason Ho, Stephanie H. Greco, Vadim P. Koshenkov, Roberto J. Vidri, Jeffrey M. Farma, and Adam C. Berger
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Oncology ,ASO Visual Abstract ,Surgery - Published
- 2022
32. Dsc E3 ligase localization to the Golgi requires the ATPase Cdc48 and cofactor Ufd1 for activation of sterol regulatory element-binding protein in fission yeast
- Author
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Risa Burr, Sumana Raychaudhuri, Diedre Ribbens, Jason Ho, Peter J. Espenshade, and Emerson V. Stewart
- Subjects
0301 basic medicine ,Glycosylation ,Recombinant Fusion Proteins ,Ubiquitin-Protein Ligases ,Golgi Apparatus ,Cell Cycle Proteins ,Biochemistry ,03 medical and health sciences ,symbols.namesake ,Valosin Containing Protein ,Schizosaccharomyces ,Immunoprecipitation ,Protein Interaction Domains and Motifs ,Golgi localization ,Molecular Biology ,Adenosine Triphosphatases ,biology ,Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ,Cell Biology ,Golgi apparatus ,biology.organism_classification ,Peptide Fragments ,AAA proteins ,Sterol regulatory element-binding protein ,Cell biology ,Protein Transport ,030104 developmental biology ,Protein Synthesis and Degradation ,Schizosaccharomyces pombe ,symbols ,Sterol Regulatory Element Binding Protein 1 ,lipids (amino acids, peptides, and proteins) ,Schizosaccharomyces pombe Proteins ,Sterol regulatory element-binding protein 2 ,Protein Multimerization ,Carrier Proteins ,Protein Processing, Post-Translational ,Gene Deletion ,Peptide Hydrolases ,Sterol Regulatory Element Binding Protein 2 ,Transcription Factors - Abstract
Sterol regulatory element-binding proteins (SREBPs) in the fission yeast Schizosaccharomyces pombe regulate lipid homeostasis and the hypoxic response under conditions of low sterol or oxygen availability. SREBPs are cleaved in the Golgi through the combined action of the Dsc E3 ligase complex, the rhomboid protease Rbd2, and the essential ATPases associated with diverse cellular activities (AAA+) ATPase Cdc48. The soluble SREBP N-terminal transcription factor domain is then released into the cytosol to enter the nucleus and regulate gene expression. Previously, we reported that Cdc48 binding to Rbd2 is required for Rbd2-mediated SREBP cleavage. Here, using affinity chromatography and mass spectrometry experiments, we identified Cdc48-binding proteins in S. pombe, generating a list of many previously unknown potential Cdc48-binding partners. We show that the established Cdc48 cofactor Ufd1 is required for SREBP cleavage but does not interact with the Cdc48-Rbd2 complex. Cdc48-Ufd1 is instead required at a step prior to Rbd2 function, during Golgi localization of the Dsc E3 ligase complex. Together, these findings demonstrate that two distinct Cdc48 complexes, Cdc48-Ufd1 and Cdc48-Rbd2, are required for SREBP activation and low-oxygen adaptation in S. pombe.
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- 2017
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33. Impact of COVID-19 on Patient-Initiated Discontinuation of Omalizumab in Two Academic Hospital Clinics at the University of Toronto
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Jensen Yeung, Jason Ho Seung Kim, and Jorge R. Georgakopoulos
- Subjects
2019-20 coronavirus outbreak ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pneumonia, Viral ,Comorbidity ,Omalizumab ,Dermatology ,Betacoronavirus ,Administration, Inhalation ,medicine ,Humans ,Anti-Asthmatic Agents ,Pandemics ,Ontario ,Withholding Treatment ,SARS-CoV-2 ,business.industry ,COVID-19 ,Asthma ,Discontinuation ,Multicenter study ,Family medicine ,Surgery ,Coronavirus Infections ,business ,medicine.drug - Published
- 2020
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34. Additive manufacturing of linear shaped charges for curved penetration
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Phillip R. Mulligan, Catherine E. Johnson, Jason Ho, and Cody S. Lough
- Subjects
Shaped charge ,Materials science ,Manufacturing process ,Explosive force ,Mechanical engineering ,Penetration (firestop) ,Selective laser melting ,Curvature ,Depth of penetration ,Penetration depth - Abstract
Linear shaped charges (LSC) are typically manufactured in continuous lengths and formed into an inverted “V”. They use explosive force to cut through a target with a straight blade, usually in the demolition industry, but there is also significant interest in cutting a circle with the LSC formation for military and breaching applications. While some curved LSCs do exist, there are limitations for the curve due to the manufacturing process; additionally depth of penetration is reduced as the blade is formed at an angle due to varying inside and outside dimensions of the LSC. The run-up/run-down effect that is prevalent with the use of LSCs also poses as an obstacle towards cutting a full circle, as the optimal penetration depth is not reached in the run-up/run-down areas. Additive manufacturing allows for geometric complexity not possible in other manufacturing techniques. In this work, selective laser melting with a Renishaw 250 system was utilized. Using additive manufacturing, two separate design challenges were addressed; reducing the amount of run-up that occurs, and producing curved penetration with the LSC blade. LSC performance was evaluated by the depth of penetration, reduction of the amount of run-up that occurs, and curvature in the cut compared to traditional liners. The aim of this work is to show the potential for reducing the amount of run-up and curving the blade of a LSC through additive manufacturing of LSC liners.
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- 2020
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35. Effect of Modulating FcRn Binding on Direct and Pretargeted Tumor Uptake of Full-length Antibodies
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Jason Ho, Christopher W. Davies, Hanine Rafidi, C. Andrew Boswell, Shang-Fan Yu, Lidia A. Nazarova, Sheila Ulufatu, James T. Koerber, Danielle Mandikian, Jeffrey Lau, Gregory Z. Ferl, Jack Sadowsky, and James A. Ernst
- Subjects
0301 basic medicine ,Cancer Research ,Single Photon Emission Computed Tomography Computed Tomography ,Receptor, ErbB-2 ,Spleen ,Breast Neoplasms ,Mice, SCID ,Receptors, Fc ,Pharmacology ,03 medical and health sciences ,Tetrazine ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Neonatal Fc receptor ,Pharmacokinetics ,Spect imaging ,medicine ,Image Processing, Computer-Assisted ,Animals ,Pretargeting ,biology ,Chemistry ,Histocompatibility Antigens Class I ,Antibodies, Monoclonal ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Click chemistry ,biology.protein ,Click Chemistry ,Female ,Antibody ,Radiopharmaceuticals - Abstract
Full-length antibodies lack ideal pharmacokinetic properties for rapid targeted imaging, prompting the pursuit of smaller peptides and fragments. Nevertheless, studying the disposition properties of antibody-based imaging agents can provide critical insight into the pharmacology of their therapeutic counterparts, particularly for those coupled with potent payloads. Here, we evaluate modulation of binding to the neonatal Fc receptor (FcRn) as a protein engineering-based pharmacologic strategy to minimize the overall blood pool background with directly labeled antibodies and undesirable systemic click reaction of radiolabeled tetrazine with circulating pretargeted trans-cyclooctene (TCO)-modified antibodies. Noninvasive SPECT imaging of mice bearing HER2-expressing xenografts was performed both directly (111In-labeled antibody) and indirectly (pretargeted TCO-modified antibody followed by 111In-labeled tetrazine). Pharmacokinetic modulation of antibodies was achieved by two distinct methods: Fc engineering to reduce binding affinity to FcRn, and delayed administration of an antibody that competes with binding to FcRn. Tumor imaging with directly labeled antibodies was feasible in the absence of FcRn binding, rapidly attaining high tumor-to-blood ratios, but accompanied by moderate liver and spleen uptake. Pretargeted imaging of tumors with non-FcRn-binding antibody was also feasible, but systemic click reaction still occurred, albeit at lower levels than with parental antibody. Our findings demonstrate that FcRn binding impairment of full-length IgG antibodies moderately lowers tumor accumulation of radioactivity, and shifts background activity from blood pool to liver and spleen. Furthermore, reduction of FcRn binding did not eliminate systemic click reaction, but yielded greater improvements in tumor-to-blood ratio when imaging with directly labeled antibodies than with pretargeting.
- Published
- 2019
36. NEK10 tyrosine phosphorylates p53 and controls its transcriptional activity
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Nasir, Haider, Previn, Dutt, Bert, van de Kooij, Jason, Ho, Luis, Palomero, Miquel Angel, Pujana, Michael, Yaffe, and Vuk, Stambolic
- Subjects
Antineoplastic Agents ,HCT116 Cells ,Substrate Specificity ,Gene Expression Regulation, Neoplastic ,HEK293 Cells ,A549 Cells ,Mutation ,MCF-7 Cells ,Humans ,NIMA-Related Kinases ,Tyrosine ,Cisplatin ,Phosphorylation ,Tumor Suppressor Protein p53 ,Gene Deletion ,Cell Proliferation - Abstract
In response to genotoxic stress, multiple kinase signaling cascades are activated, many of them directed towards the tumor suppressor p53, which coordinates the DNA damage response (DDR). Defects in DDR pathways lead to an accumulation of mutations that can promote tumorigenesis. Emerging evidence implicates multiple members of the NimA-related kinase (NEK) family (NEK1, NEK10, and NEK11) in the DDR. Here, we describe a function for NEK10 in the regulation of p53 transcriptional activity through tyrosine phosphorylation. NEK10 loss increases cellular proliferation by modulating the p53-dependent transcriptional output. NEK10 directly phosphorylates p53 on Y327, revealing NEK10's unexpected substrate specificity. A p53 mutant at this site (Y327F) acts as a hypomorph, causing an attenuated p53-mediated transcriptional response. Consistently, NEK10-deficient cells display heightened sensitivity to DNA-damaging agents. Further, a combinatorial score of NEK10 and TP53-target gene expression is an independent predictor of a favorable outcome in breast cancers.
- Published
- 2019
37. Beneficial visual outcome of vitrectomy and delamination surgery for tractional complications of diabetic retinopathy in a cohort of black patients
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D Alistair H Laidlaw, Jason Ho, Tom H. Williamson, and Roger Wong
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Adult ,Male ,medicine.medical_specialty ,Visual acuity ,Time Factors ,genetic structures ,medicine.medical_treatment ,Visual Acuity ,Black People ,Vitrectomy ,Case review ,Article ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Primary outcome ,medicine ,Humans ,Aged ,Retrospective Studies ,Diabetic Retinopathy ,business.industry ,Incidence ,Mean age ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,eye diseases ,United Kingdom ,Surgery ,Ophthalmology ,Treatment Outcome ,Cohort ,030221 ophthalmology & optometry ,Female ,Tamponade ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
BACKGROUND/AIMS: Poor visual outcomes have recently been reported in black patients undergoing vitrectomy and delamination surgery for complications of proliferative diabetic retinopathy. We therefore investigated the outcome of surgery on a similar cohort of black patients and examined for potential predictors of visual success. METHODS: A single-centre retrospective case review of consecutive black patients who underwent vitrectomy and delamination surgery for complications of PDR between July 2010 and September 2017. The primary outcome measure was change in visual acuity (VA) at 6 months post-operatively. Multiple linear regression analysis was performed to evaluate determinants of change in VA. RESULTS: A total of 44 eyes of 44 patients were included. Mean age was 53.7 (range: 24.3–75.8) years. In all, 43% were male. A total of 52% had adjunctive pre-operative anti-VEGF therapy. Mean pre-operative VA was 1.49 logMAR ± 0.73 (range 0.18 to 2.6 logMAR). Mean change in VA at 6 months was a gain of 0.59 ± 0.94 logMAR (range 1.9 logMAR acuity loss to 2.5 logMAR acuity gain). Four cases required further surgery to treat rhegmatogenous detachment. The acuity of 68% improved by 0.3 or more logMAR. Silicone oil was used as primary tamponade in 7%. Pre-operative VA and use of silicone oil significantly predicted VA decline at 6 months (p = 0.001 and p = 0.007). CONCLUSIONS: The majority of our cohort derived visual benefit from vitrectomy and delamination for PDR-related complications. Improvement in VA was comparable to outcomes from the UK National Ophthalmic Database report. Silicone oil should be avoided these patients if possible.
- Published
- 2019
38. National survey of the management of eye emergencies in the accident and emergency department by foundation doctors: has anything changed over the past 15 years?
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Chuiki Jasmine La, Jonathan Than, Jason Ho, and Peng Yong Sim
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business.industry ,Accident and emergency ,education ,Workload ,medicine.disease ,Confidence interval ,Article ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Surveys and Questionnaires ,030221 ophthalmology & optometry ,medicine ,Medical Staff, Hospital ,Humans ,Medical emergency ,Prospective Studies ,Emergencies ,business ,Emergency Service, Hospital ,030217 neurology & neurosurgery - Abstract
BACKGROUND: Ophthalmic emergencies comprise a significant portion of junior doctors’ workload in accident and emergency (A&E). However, previous studies have demonstrated a lack of training and confidence in the management of such emergencies. This study assessed changes in basic ophthalmic training that A&E junior doctors received in dealing with eye emergencies, their perceived level of confidence and the availability of appropriate ophthalmic equipment in A&E over the last 15 years. METHODS: A prospective, national, combined online and telephone survey using a previously published questionnaire was performed. Foundation year two doctors (FY2s) from each A&E department in the UK listed on the official NHS directory were contacted for participation. RESULTS: Two hundred and ten A&E departments were contacted and 202 responded (response rate of 96.2%). There was no significant change in the number of A&E departments equipped with slit lamps (82.5% in 2003 vs 79.7% in 2018; p = 0.26). However, the prevalence of training in its use has decreased significantly (68.4% in 2003 vs 52% in 2018; p = 0.005). There was also a significant reduction in the prevalence of training in the management of eye emergencies (77.4% in 2003 vs 45.5% in 2018; p
- Published
- 2019
39. A comparison of 23-gauge and 20-gauge vitrectomy for proliferative sickle cell retinopathy – clinical outcomes and surgical management
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Anna Grabowska, Mahiul M. K. Muqit, Jason Ho, and Marta Ugarte
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Adult ,Male ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Adolescent ,medicine.medical_treatment ,Visual Acuity ,Vitrectomy ,Anemia, Sickle Cell ,Article ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Retinal Diseases ,Ophthalmology ,medicine ,Humans ,Macular hole ,Aged ,Retrospective Studies ,business.industry ,Retinal detachment ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,eye diseases ,030221 ophthalmology & optometry ,Female ,sense organs ,Epiretinal membrane ,medicine.symptom ,Complication ,business ,030217 neurology & neurosurgery ,Retinopathy - Abstract
AIMS: To report anatomical and functional outcomes in patients with proliferative sickle retinopathy (PSR) who underwent 23-gauge (23G) and 20-gauge (20G) vitrectomy. METHODS: Retrospective consecutive case series of patients who underwent vitreoretinal intervention for complications of PSR between April 2009 and February 2015. Operations were performed at a tertiary referral centre, Moorfields Eye Hospital. Visual acuity and anatomical success rates were evaluated for PSR complicated by retinal detachment, tractional vitreous haemorrhage and macular hole. Proliferative diabetic retinopathy cases were excluded. RESULTS: A total of 71 eyes (63 patients) underwent vitreoretinal surgery for PSR complications with 26 months mean follow-up. Primary indications were: tractional retinal detachment (TRD, n = 17), TRD with rhegmatogenous retinal detachment (n = 16), rhegmatogenous retinal detachment (n = 5, macula-on: 1, macula-off: 4), vitreous haemorrhage (n = 19), epiretinal membrane (n = 6), and full thickness macula hole (n = 8). Thirty-nine cases underwent 20G vitrectomy, and 23G surgery was performed in 32 eyes. Mean best corrected visual acuity (BCVA) improved from pre-operative 1.30 LogMAR to final BCVA of 0.74 LogMAR (p
- Published
- 2018
40. Intravitreal ocriplasmin for the treatment of vitreomacular traction and macular hole- A study of efficacy and safety based on NICE guidance
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Helen Buck, Robin Hamilton, Mahiul M. K. Muqit, Sally Tucker, and Jason Ho
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Male ,genetic structures ,Vision ,Visual Acuity ,Social Sciences ,lcsh:Medicine ,Vitreomacular traction ,Diagnostic Radiology ,chemistry.chemical_compound ,0302 clinical medicine ,Vitrectomy ,Medicine and Health Sciences ,Psychology ,Fibrinolysin ,lcsh:Science ,Macular hole ,Tomography ,Multidisciplinary ,Radiology and Imaging ,Ophthalmic Procedures ,Cataract Surgery ,Research Design ,Intravitreal Injections ,Practice Guidelines as Topic ,Full thickness ,Female ,Sensory Perception ,Safety ,Anatomy ,Tomography, Optical Coherence ,Research Article ,medicine.medical_specialty ,Standard of care ,Imaging Techniques ,Clinical Research Design ,Ocular Anatomy ,Surgical and Invasive Medical Procedures ,Research and Analysis Methods ,Retina ,Nice guidance ,03 medical and health sciences ,Diagnostic Medicine ,Ocular System ,Ophthalmology ,medicine ,Humans ,In patient ,Adverse effect ,Vision, Ocular ,Aged ,business.industry ,Ocriplasmin ,lcsh:R ,Biology and Life Sciences ,medicine.disease ,Retinal Perforations ,Peptide Fragments ,eye diseases ,chemistry ,030221 ophthalmology & optometry ,lcsh:Q ,Adverse Events ,business ,030217 neurology & neurosurgery ,Neuroscience - Abstract
PURPOSE To evaluate the real world clinical outcomes of intravitreal ocriplasmin in patients with vitreomacular traction (VMT) with and without full thickness macular holes (FTMH) treated according to NICE guidance. METHODS Retrospective observational case series of 25 patients treated with a single intravitreal ocriplasmin injection between December 2013 and December 2015. Best corrected visual acuity and optical coherence tomography exams were performed to determine visual outcomes and anatomical VMT release and FTMH closure over time. Two patient groups were identified: ocular macular co-morbidity (OCM) and no OCM (nOCM), with follow-up at 4, 12, and 24 weeks. RESULTS Twenty-five patients were identified that included 19 patients with VMT, and 6 patients with VMT plus FTMH. In the nOCM group of 22 patients, the release rate of VMT was 44%, 63%, and 69% at 4, 12 and 24 weeks respectively. In the "real-world" OCM group of 25 patients, the VMT release rate was 37%, 53%, and 58% at the same time-points. In both groups, the FTMH closure rate was 33%, 50%, and 67% at 4, 12, and 24 weeks. At mean follow-up of 30 weeks in the VMT group with nOCM, the mean LogMAR VA improved significantly from 0.44 to 0.28 (p = 0.0068, paired t-test). Three were no serious adverse events. CONCLUSIONS This study reports improved efficacy of intravitreal ocriplasmin for both VMT and FTMH, and is more favourable in patients with no ocular co-morbidity. We highlight the importance of careful patient selection and structured standard of care pathways to identify patients who will benefit from the positive visual and anatomical effects of intravitreal ocriplasmin.
- Published
- 2018
41. Who Decides What to Watch on TV at Home? Insights from People-Meter Data in Mexico
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José-Domingo Mora, Jason Ho, and Robert E. Krider
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Marketing ,People meter ,Co viewing ,Communication ,Interpersonal influence ,Television viewers ,Advertising ,Business ,Affect (psychology) ,Preference - Abstract
How do household members influence one another9s television-viewing behaviors, and how can these behaviors affect new programming? The current study offers a method to separate two different sources of interpersonal influence among television viewers in the same household: what the authors call “social co-viewing” and the intrinsic preferences of another viewer independent of co-viewing. Applying the method to people-meter data from Mexico, the researchers found that, ultimately, wives were more influential than husbands in building audiences. The authors believe their method can be applied to any people-meter data, providing insight for programmers promoting new shows and for advertisers choosing programs to sponsor in the upfront market.
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- 2015
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42. Relative Target Affinities of T-Cell-Dependent Bispecific Antibodies Determine Biodistribution in a Solid Tumor Mouse Model
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Danielle Mandikian, C. Andrew Boswell, Jason Ho, Teemu T. Junttila, Kedan Lin, Maria Hristopoulos, Amy C. Y. Lo, Mark S. Dennis, Saileta Prabhu, Robyn Clark, Jeffrey Eastham-Anderson, Ji Li, Klara Totpal, Dionysos Slaga, Nene Takahashi, and Sean B. Joseph
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0301 basic medicine ,Cancer Research ,Biodistribution ,CD3 Complex ,Receptor, ErbB-2 ,medicine.medical_treatment ,T cell ,CD3 ,Antibody Affinity ,Mice, Nude ,Mice, Transgenic ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Cancer immunotherapy ,Antibodies, Bispecific ,medicine ,Tumor Cells, Cultured ,Cytotoxic T cell ,Animals ,Humans ,Tissue Distribution ,biology ,Chemistry ,Immunotherapy ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Cancer cell ,Colonic Neoplasms ,Cancer research ,biology.protein ,Female ,Antibody ,T-Lymphocytes, Cytotoxic - Abstract
Anti-HER2/CD3, a T-cell–dependent bispecific antibody (TDB) construct, induces T-cell–mediated cell death in cancer cells expressing HER2 by cross-linking tumor HER2 with CD3 on cytotoxic T cells, thereby creating a functional cytolytic synapse. TDB design is a very challenging process that requires consideration of multiple parameters. Although therapeutic antibody design strategy is commonly driven by striving for the highest attainable antigen-binding affinity, little is known about how the affinity of each TDB arm can affect the targeting ability of the other arm and the consequent distribution and efficacy. To our knowledge, no distribution studies have been published using preclinical models wherein the T-cell–targeting arm of the TDB is actively bound to T cells. We used a combined approach involving radiochemistry, invasive biodistribution, and noninvasive single-photon emission tomographic (SPECT) imaging to measure TDB distribution and catabolism in transgenic mice with human CD3ϵ expression on T cells. Using CD3 affinity variants, we assessed the impact of CD3 affinity on short-term pharmacokinetics, tissue distribution, and cellular uptake. Our experimental approach determined the relative effects of (i) CD3 targeting to normal tissues, (ii) HER2 targeting to HER2-expressing tumors, and (iii) relative HER2/CD3 affinity, all as critical drivers for TDB distribution. We observed a strong correlation between CD3 affinity and distribution to T-cell–rich tissues, with higher CD3 affinity reducing systemic exposure and shifting TDB distribution away from tumor to T-cell–containing tissues. These observations have important implications for clinical translation of bispecific antibodies for cancer immunotherapy. Mol Cancer Ther; 17(4); 776–85. ©2018 AACR.
- Published
- 2017
43. PTEN Nuclear Functions
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Vuk Stambolic, Ryan J.O. Dowling, Jason Ho, and Edward S. Cruise
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DNA Replication ,0301 basic medicine ,DNA Repair ,DNA repair ,Apoptosis ,Disease ,Biology ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Animals ,Humans ,PTEN ,Cell Nucleus ,Cell Cycle ,PTEN Phosphohydrolase ,DNA replication ,Cancer ,medicine.disease ,030104 developmental biology ,030220 oncology & carcinogenesis ,biology.protein ,Autism ,Neuroscience ,Function (biology) ,Nuclear localization sequence ,Perspectives ,Signal Transduction - Abstract
For years, clinical and basic researchers have been aware of the presence of PTEN in the nucleus in cell culture, animal models, and both healthy and diseased human tissues. Despite the early recognition of nuclear PTEN, the understanding of the mechanisms of its nuclear localization, function in the nucleus, and importance in biology and human disease has been lacking. Over the last decade, emerging concepts for the complex involvement of nuclear PTEN in a variety of processes, including genome maintenance and DNA repair, cell-cycle control, gene expression, and DNA replication, are illuminating what could prove to be the key path toward a full understanding of PTEN function in health and disease. Dysregulation of nuclear PTEN is now considered an important aspect of the etiology of many pathologic conditions, prompting reconsideration of the therapeutic approaches aimed at countering the consequences of PTEN deficiency. This new knowledge is fueling the development of innovative therapeutic modalities for a broad spectrum of human conditions, from cancer and metabolic diseases, to neurological disorders and autism.
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- 2019
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44. Nuclear PTEN Controls DNA Repair and Sensitivity to Genotoxic Stress
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Jason Ho, Rjo J. O. Dowling, Tharan Srikumar, Christian Bassi, Vuk Stambolic, Tw W. Mak, Sj J. Miller, Brian Raught, Chiara Gorrini, and Bg G. Neel
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Ataxia Telangiectasia Mutated Proteins ,Multidisciplinary ,Tumor suppressor gene ,biology ,DNA repair ,SUMO protein ,biology.protein ,Cancer research ,Tensin ,PTEN ,Genotoxic Stress ,PI3K/AKT/mTOR pathway - Abstract
PTEN Variations The product of the tumor suppressor gene phosphate and tensin homolog on chromosome ten ( PTEN) is a lipid and protein phosphatase that regulates important cellular processes, including growth, survival, and metabolism (see the Perspective by Leslie and Brunton ). Though PTEN is best known for effects on the phosphatidylnositol 3-kinase (PI3K) signaling pathway, the PTEN protein is also found in the nucleus. Bassi et al. (p. 395 ) found that PTEN's presence in the nucleus was regulated in response to covalent modification of the protein by SUMOylation and phosphorylation. Cells lacking nuclear PTEN showed increased sensitivity to DNA damage and underwent cell death if the PI3K pathway was also inhibited. Hopkins et al. (p. 399 , published online 6 June) discovered an alternative translation start site in human PTEN messenger RNA that allowed expression of a protein, PTEN-Long, with about 170 extra amino acids. The unusual enzyme was released from cells and then taken up into other cells. In a mouse tumor model, uptake of the enzyme inhibited the PI3K pathway and inhibited tumor growth.
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- 2013
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45. Characterization of Plasmablasts in the Blood of HIV-Infected Viremic Individuals: Evidence for Nonspecific Immune Activation
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Emily K. Funk, Anthony S. Fauci, Lela Kardava, Susan Moir, Yuxing Li, Jacqueline G. Posada, Tae-Wook Chun, Amy Nelson, Clarisa M. Buckner, Wei Wang, and Jason Ho
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Adult ,Male ,Cellular differentiation ,Plasma Cells ,Immunology ,HIV Infections ,Viremia ,Microbiology ,Immunoglobulin G ,Young Adult ,Immune system ,Hypergammaglobulinemia ,Virology ,medicine ,Humans ,Young adult ,biology ,virus diseases ,Cell Differentiation ,Middle Aged ,medicine.disease ,Vaccination ,Immunization ,Insect Science ,biology.protein ,Pathogenesis and Immunity ,Female - Abstract
Terminal differentiation of B cells and hypergammaglobulinemia are hallmarks of B-cell hyperactivity in HIV disease. Plasmablasts are terminally differentiating B cells that circulate transiently in the blood following infection or vaccination; however, in HIV infection, they arise early and are maintained at abnormally high levels in viremic individuals. Here we show that only a small fraction of plasmablasts in the blood of viremic individuals is HIV specific. Assessment of plasmablast immunoglobulin isotype distribution revealed increased IgG + plasmablasts in early and most prominently during chronic HIV viremia, contrasting with a predominantly IgA + plasmablast profile in HIV-negative individuals or in aviremic HIV-infected individuals on treatment. Of note, IgG is the predominant immunoglobulin isotype of plasmablasts that arise transiently in the blood following parenteral immunization. Serum immunoglobulin levels were also elevated in HIV-infected viremic individuals, especially IgG, and correlated with levels of IgG + plasmablasts. Several soluble factors associated with immune activation were also increased in the sera of HIV-infected individuals, especially in viremic individuals, and correlated with serum immunoglobulin levels, particularly IgG. Thus, our data suggest that while plasmablasts in the blood may contribute to the HIV-specific immune response, the majority of these cells are not HIV specific and arise early, likely from indirect immune-activating effects of HIV replication, and reflect over time the effects of chronic antigenic stimulation. Such B-cell dysregulation may help explain why the antibody response is inadequate in HIV-infected individuals, even during early infection.
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- 2013
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46. Convergence of dispersed regulatory mutations predicts driver genes in prostate cancer
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Nicholas A Sinnott-Armstrong, Jason Ho, Ken Kron, Stacey L. Edwards, Richard C Sallari, Vuk Stambolic, Juliet D. French, Manolis Kellis, Jason H. Moore, and Mathieu Lupien
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Genetics ,0303 health sciences ,Cancer ,Genomics ,Biology ,medicine.disease ,Genome ,Chromatin ,Transcriptome ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Regulatory sequence ,medicine ,Gene ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
Cancer sequencing predicts driver genes using recurrent protein-altering mutations, but detecting recurrence for non-coding mutations remains unsolved. Here, we present a convergence framework for recurrence analysis of non-coding mutations using three-dimensional co-localization of epigenomically-identified regions. We define the regulatory plexus of each gene as its cell-type-specific three-dimensional gene-regulatory neighborhood, inferred using Hi-C chromosomal interactions and chromatin state annotations. Using 16 matched tumor-normal prostate transcriptomes, we predict tumor-upregulated genes, and find enriched plexus mutations in distal regulatory regions normally repressed in prostate, suggesting out-of-context de-repression. Using 55 matched tumor-normal prostate genomes, we predict 15 driver genes by convergence of dispersed, low-frequency mutations into high-frequency dysregulation events along prostate-specific plexi, while controlling for mutational heterogeneity across regions, chromatin states, and patients. These putative drivers play roles in growth signaling, immune evasion, mitochondrial function, and vascularization, suggesting higher-order pathway-level convergence. We experimentally validate the PLCB4 plexus and its ability to affect the canonical PI3K cancer pathway.
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- 2016
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47. COMPARISON OF LIFE CYCLE COST OF CENTRALIZED AND SPLIT AIR CONDITIONING SYSTEMS
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Dharma Hagare, Jason Ho, and Swapan Saha
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Waste management ,Air conditioning ,business.industry ,Geography, Planning and Development ,Environmental science ,Development ,business - Abstract
Central and split systems are the two most common air conditioning (AC) systems used in residential applications. Central system employs one large unit to produce and distribute conditioned air through a system of ductwork. On the other hand, the split system, employs several small ACs. Each AC consisted of outdoor and indoor units to produce conditioned air directly to the designed area. Each system has distinct strengths and weaknesses. Depending on the structure of cooling area and operating schedule, the performance of each system will be different. The aim of this paper is to examine the impact of various parameters such as operating schedule and building characteristics to the performance of central and split AC systems over the 25 years of their operation. The life cycle analysis (LCA) considered essential factors which have significant impact on the energy consumption and both initial and operating costs of the two systems. All required sections of life cycle analysis are included according to the relevant Australian Standards. The results indicated that under standard operating conditions, central system is more economical and energy efficient than split system. However, when the flexibility in operation of split system is considered, there was a significant reduction in its operating cost, which was below that of central system. Overall, total life cycle cost of split system was slightly lower than central system. Also, considering the usage flexibility and the comfort of users, it appears that the split system is more suitable than the central AC system for residential buildings.
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- 2016
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48. Head pose estimation and its application in TV viewers' behavior analysis
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Jie Liang, Jason Ho, and Siyu Wu
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Computer science ,business.industry ,020208 electrical & electronic engineering ,Pattern recognition ,02 engineering and technology ,3D pose estimation ,Support vector machine ,Gabor filter ,Region of interest ,Histogram ,Face (geometry) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,business ,Pose - Abstract
Head pose implies a person's visual attention and interest. It plays an important role in many applications. Existing head pose estimation methods work in the original head pose space. However, the large number of head pose candidates in the space makes the estimation task quite challenging. In this paper, we propose a coarse-to-fine head pose estimation method by decomposing the original pose space into a hierarchical structure. The estimation begins by detecting the region of interest (ROI) within a face image via measuring the importance scores of key image points. After that, a coarse head pose estimation step is applied to identify a subset of head pose candidates, based on Gabor filter and random forest. A fine estimation is then employed within the subset, using histogram of oriented gradient (HOG) and support vector machine (SVM). Finally, we apply the proposed method to TV viewers' behavior analysis by determining whether a viewer is focused or unfocused, which can be useful for marketing research.
- Published
- 2016
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49. Effects of Anti-VEGF on Pharmacokinetics, Biodistribution, and Tumor Penetration of Trastuzumab in a Preclinical Breast Cancer Model
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Kathryn L Parsons-Reponte, Eduardo E. Mundo, Leslie A. Khawli, Frank-Peter Theil, Nicholas Lewin-Koh, Cinthia V. Pastuskovas, Daniela Bumbaca, Jason Ho, C. Andrew Boswell, Eric Cheng, Jay Tibbitts, Sarajane Ross, Mark X. Sliwkowski, Sheila Bheddah, Sheila Ulufatu, Katherine R. Kozak, Suzanna Clark, Marjie Van Hoy, Nicholas Majidy, Josefa Chuh, Simon Williams, Paul J. Fielder, Tapan K. Nayak, Gary Cain, and Peter Nauka
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Vascular Endothelial Growth Factor A ,Cancer Research ,Biodistribution ,Bevacizumab ,Receptor, ErbB-2 ,Antibody Affinity ,Mice, Nude ,Breast Neoplasms ,Vascular permeability ,Pharmacology ,Antibodies, Monoclonal, Humanized ,Multimodal Imaging ,Iodine Radioisotopes ,Mice ,Breast cancer ,Pharmacokinetics ,Antibody Specificity ,Trastuzumab ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Tissue Distribution ,skin and connective tissue diseases ,Dose-Response Relationship, Drug ,business.industry ,Indium Radioisotopes ,Antibodies, Monoclonal ,medicine.disease ,Immunohistochemistry ,Xenograft Model Antitumor Assays ,Oncology ,Positron-Emission Tomography ,Female ,Tomography, X-Ray Computed ,business ,Perfusion ,medicine.drug - Abstract
Both human epidermal growth factor receptor 2 (HER-2/neu) and VEGF overexpression correlate with aggressive phenotypes and decreased survival among breast cancer patients. Concordantly, the combination of trastuzumab (anti-HER2) with bevacizumab (anti-VEGF) has shown promising results in preclinical xenograft studies and in clinical trials. However, despite the known antiangiogenic mechanism of anti-VEGF antibodies, relatively little is known about their effects on the pharmacokinetics and tissue distribution of other antibodies. This study aimed to measure the disposition properties, with a particular emphasis on tumor uptake, of trastuzumab in the presence or absence of anti-VEGF. Radiolabeled trastuzumab was administered alone or in combination with an anti-VEGF antibody to mice bearing HER2-expressing KPL-4 breast cancer xenografts. Biodistribution, autoradiography, and single-photon emission computed tomography–X-ray computed tomography imaging all showed that anti-VEGF administration reduced accumulation of trastuzumab in tumors despite comparable blood exposures and similar distributions in most other tissues. A similar trend was also observed for an isotype-matched IgG with no affinity for HER2, showing reduced vascular permeability to macromolecules. Reduced tumor blood flow (P < 0.05) was observed following anti-VEGF treatment, with no significant differences in the other physiologic parameters measured despite immunohistochemical evidence of reduced vascular density. In conclusion, anti-VEGF preadministration decreased tumor uptake of trastuzumab, and this phenomenon was mechanistically attributed to reduced vascular permeability and blood perfusion. These findings may ultimately help inform dosing strategies to achieve improved clinical outcomes. Mol Cancer Ther; 11(3); 752–62. ©2012 AACR.
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- 2012
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50. Television Co-Viewing in Mexico: An Assessment on People Meter Data
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Jason Ho, José-Domingo Mora, and Robert E. Krider
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People meter ,Data set ,Measure (data warehouse) ,Co viewing ,Multimedia ,Computer science ,Communication ,Advertising ,computer.software_genre ,computer ,Panel data - Abstract
Television co-viewing is a frequent behavior with important social and economic implications. This study proposes a measure of co-viewing on people meter panel data, tests it on a data set in Mexic...
- Published
- 2011
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