45 results on '"Schwarz LJ"'
Search Results
2. MYC and MCL1 Cooperatively Promote Chemotherapy-Resistant Breast Cancer Stem Cells via Regulation of Mitochondrial Oxidative Phosphorylation
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Lee KM, Giltnane JM, Balko JM, Schwarz LJ, Guerrero-Zotano AL, Hutchinson KE, Nixon MJ, Estrada MV, Sánchez V, Sanders ME, Lee T, Gómez H, Lluch A, Pérez-Fidalgo JA, Wolf MM, Andrejeva G, Rathmell JC, Fesik SW, and Arteaga CL
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- 2017
3. Abstract PD5-02: Not presented
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Guerrero-Zotano, AL, primary, Stricker, TP, additional, Hutchinson, KE, additional, Stover, DG, additional, Formisano, L, additional, Lee, K-M, additional, Schwarz, LJ, additional, Giltnane, JM, additional, Jansen, VM, additional, Gavila, J, additional, Perez-Fidalgo, A, additional, Lluch, A, additional, Llombart, A, additional, Bayar, MA, additional, Michiels, S, additional, André, F, additional, Arnedos, M, additional, Ruiz, A, additional, and Arteaga, CL, additional
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- 2018
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4. Abstract GS6-05: Gain-of-function kinase library screen identifies FGFR1 amplification as a mechanism of resistance to antiestrogens and CDK4/6 inhibitors in ER+ breast cancer
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Formisano, L, primary, Lu, Y, additional, Jansen, VM, additional, Bauer, JA, additional, Hanker, A, additional, Gonzalez Ericsson, P, additional, Lee, K-M, additional, Nixon, MJ, additional, Guerrero-Zotano, AL, additional, Schwarz, LJ, additional, Sanders, M, additional, Sudhan, D, additional, Dugger, TC, additional, Cruz, MR, additional, Behdad, A, additional, Cristofanilli, M, additional, Bardia, A, additional, O'Shaughnessy, J, additional, Mayer, IA, additional, and Arteaga, CL, additional
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- 2018
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5. Abstract P1-13-08: Extended adjuvant neratinib/fulvestrant blocks ER/HER2 crosstalk and maintains complete responses of ER+/HER2+ tumors following treatment with chemotherapy and anti-HER2 therapy
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Sudhan, DR, primary, Schwarz, LJ, additional, Guerrero-Zotano, AL, additional, Nixon, M, additional, Formisano, L, additional, Croessmann, S, additional, Gonzalez Ericsson, PI, additional, Sanders, ME, additional, Balko, JM, additional, Avogadri-Connors, F, additional, Cutler, RE, additional, Lalani, AS, additional, Bryce, R, additional, Auerbach, A, additional, and Arteaga, CL, additional
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- 2018
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6. Abstract P6-12-09: Pan-HER, an antibody mixture with antitumor activity against drug-resistant HER2-overexpressing breast cancers with high ERBB ligand expression
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Schwarz, LJ, primary, Hutchinson, KE, additional, Estrada, MV, additional, Sanders, ME, additional, Dugger, TC, additional, Formisano, L, additional, Guerrero, AL, additional, Red-Brewer, M, additional, Young, CD, additional, Lantto, J, additional, Pedersen, MW, additional, Kragh, M, additional, Horak, ID, additional, and Arteaga, CL, additional
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- 2017
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7. Abstract P2-10-01: Genomic profiling of residual ER+ breast cancers treated with prolonged neoadjuvant letrozole reveals novel alterations in clinically resistant tumors
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Guerrero, AL, primary, Stricker, T, additional, Hutchinson, KE, additional, Formisano, L, additional, Giltnane, J, additional, Fidalgo, A, additional, Schwarz, LJ, additional, Gavila, J, additional, Guillen, V, additional, Lluch, A, additional, Ruiz, A, additional, and Arteaga, CL, additional
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- 2017
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8. Abstract S6-01: JAK2 amplifications are enriched in triple negative breast cancers (TNBCs) after neoadjuvant chemotherapy and predict poor prognosis
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Balko, JM, primary, Giltnane, JM, additional, Schwarz, LJ, additional, Sanders, ME, additional, Wang, K, additional, Harris, LN, additional, Lin, NU, additional, Miller, VA, additional, Stephens, PJ, additional, Yelensky, R, additional, Pinto, JA, additional, Gomez, H, additional, and Arteaga, CL, additional
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- 2013
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9. Abstract P6-07-21: Signs and symptoms at central nervous system (CNS) relapse in breast cancer patients with Leptomeningeal carcinomatosis related with shorter survival after recurrence
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Gomez, HL, primary, Schwarz, LJ, additional, Vásquez, J, additional, Neciosup, SP, additional, Pinto, JA, additional, Vidaurre, T, additional, Ferreyros, G, additional, and Vallejos, CS, additional
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- 2012
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10. Aberrant FGFR signaling mediates resistance to CDK4/6 inhibitors in ER+ breast cancer
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Valerie M. Jansen, Yao Lu, Paula Gonzalez Ericsson, Wei He, Luis J. Schwarz, Richard B. Lanman, Dhivya R. Sudhan, Yu Shyr, Teresa C. Dugger, Yan Guo, Carlos L. Arteaga, Marcelo Rocha Cruz, Alberto Servetto, Ingrid A. Mayer, Amir Behdad, Aditya Bardia, Luigi Formisano, Sarah Croessmann, Nadia Solovieff, Angel Guerrero-Zotano, Fei Su, Michelle Miller, Justin M. Balko, Mellissa J. Nixon, Joyce O'Shaughnessy, Ariella B. Hanker, Kyungmin Lee, Melinda E. Sanders, Massimo Cristofanilli, Joshua A. Bauer, Rebecca J. Nagy, Formisano, L, Lu, Y, Servetto, A, Hanker, Ab, Jansen, Vm, Bauer, Ja, Sudhan, Dr, Guerrero-Zotano, Al, Croessmann, S, Guo, Y, Ericsson, Pg, Lee, Km, Nixon, Mj, Schwarz, Lj, Sanders, Me, Dugger, Tc, Cruz, Mr, Behdad, A, Cristofanilli, M, Bardia, A, O'Shaughnessy, J, Nagy, Rj, Lanman, Rb, Solovieff, N, He, W, Miller, M, Su, F, Shyr, Y, Mayer, Ia, Balko, Jm, and Arteaga, Cl.
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0301 basic medicine ,Pyridines ,General Physics and Astronomy ,Aminopyridines ,02 engineering and technology ,Drug resistance ,Tyrosine-kinase inhibitor ,Piperazines ,Circulating Tumor DNA ,chemistry.chemical_compound ,Mice ,Erdafitinib ,Antineoplastic Combined Chemotherapy Protocols ,Cyclin D1 ,lcsh:Science ,Abemaciclib ,Fulvestrant ,cancer cell ,Multidisciplinary ,drug ,High-Throughput Nucleotide Sequencing ,021001 nanoscience & nanotechnology ,Progression-Free Survival ,3. Good health ,inhibitor ,Receptors, Estrogen ,MCF-7 Cells ,Quinolines ,Female ,biological phenomena, cell phenomena, and immunity ,0210 nano-technology ,medicine.drug ,Signal Transduction ,identification method ,Antineoplastic Agents, Hormonal ,medicine.drug_class ,Science ,Breast Neoplasms ,Palbociclib ,Naphthalenes ,General Biochemistry, Genetics and Molecular Biology ,Article ,resistance ,03 medical and health sciences ,Breast cancer ,Quinoxalines ,medicine ,Animals ,Humans ,Progression-free survival ,Receptor, Fibroblast Growth Factor, Type 1 ,Receptor, Fibroblast Growth Factor, Type 2 ,Protein Kinase Inhibitors ,Proportional Hazards Models ,business.industry ,Cyclin-Dependent Kinase 4 ,General Chemistry ,DNA ,Cyclin-Dependent Kinase 6 ,medicine.disease ,Xenograft Model Antitumor Assays ,stomatognathic diseases ,030104 developmental biology ,chemistry ,Drug Resistance, Neoplasm ,Purines ,Mutation ,Cancer research ,Pyrazoles ,lcsh:Q ,survival tumor ,business - Abstract
Using an ORF kinome screen in MCF-7 cells treated with the CDK4/6 inhibitor ribociclib plus fulvestrant, we identified FGFR1 as a mechanism of drug resistance. FGFR1-amplified/ER+ breast cancer cells and MCF-7 cells transduced with FGFR1 were resistant to fulvestrant ± ribociclib or palbociclib. This resistance was abrogated by treatment with the FGFR tyrosine kinase inhibitor (TKI) lucitanib. Addition of the FGFR TKI erdafitinib to palbociclib/fulvestrant induced complete responses of FGFR1-amplified/ER+ patient-derived-xenografts. Next generation sequencing of circulating tumor DNA (ctDNA) in 34 patients after progression on CDK4/6 inhibitors identified FGFR1/2 amplification or activating mutations in 14/34 (41%) post-progression specimens. Finally, ctDNA from patients enrolled in MONALEESA-2, the registration trial of ribociclib, showed that patients with FGFR1 amplification exhibited a shorter progression-free survival compared to patients with wild type FGFR1. Thus, we propose breast cancers with FGFR pathway alterations should be considered for trials using combinations of ER, CDK4/6 and FGFR antagonists., Era+ breast cancer patients often develop resistance to endocrine therapy. Here, the authors show that FGFR1 amplification is a resistance mechanism to CDK4/6 inhibitor and endocrine therapy and that combined treatment with FGFR, CDK4/6, and anti-estrogens is a potential therapeutic strategy in Era+ breast cancer tumors.
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- 2019
11. Extended Adjuvant Therapy with Neratinib Plus Fulvestrant Blocks ER/HER2 Crosstalk and Maintains Complete Responses of ER+/HER2+ Breast Cancers: Implications to the ExteNET Trial
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Mellissa J. Nixon, Sarah Croessmann, Justin M. Balko, Carlos L. Arteaga, Paula Gonzalez Ericsson, Alshad S. Lalani, Melinda E. Sanders, Dhivya R. Sudhan, Francesca Avogadri-Connors, Angel Guerrero-Zotano, Alan Auerbach, Richard Bryce, Luigi Formisano, Luis J. Schwarz, Richard E. Cutler, Sudhan, Dr, Schwarz, Lj, Guerrero-Zotano, A, Formisano, L, Nixon, Mj, Croessmann, S, González Ericsson, Pi, Sanders, M, Balko, Jm1, Avogadri-Connors, F, Cutler, Re, Lalani, A, Bryce, R, Auerbach, A, and Arteaga, Cl.
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0301 basic medicine ,Cancer Research ,Receptor, ErbB-2 ,Breast Neoplasms ,Article ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cyclin D1 ,Trastuzumab ,ErbB ,Cell Line, Tumor ,Antineoplastic Combined Chemotherapy Protocols ,Biomarkers, Tumor ,medicine ,Adjuvant therapy ,Animals ,Humans ,skin and connective tissue diseases ,Fulvestrant ,business.industry ,Immunohistochemistry ,Xenograft Model Antitumor Assays ,Disease Models, Animal ,Treatment Outcome ,030104 developmental biology ,Receptors, Estrogen ,Oncology ,Paclitaxel ,chemistry ,Chemotherapy, Adjuvant ,030220 oncology & carcinogenesis ,Neratinib ,Quinolines ,Cancer research ,Female ,Pertuzumab ,business ,medicine.drug - Abstract
Purpose:The phase III ExteNET trial showed improved invasive disease-free survival in patients with HER2+ breast cancer treated with neratinib versus placebo after trastuzumab-based adjuvant therapy. The benefit from neratinib appeared to be greater in patients with ER+/HER2+ tumors. We thus sought to discover mechanisms that may explain the benefit from extended adjuvant therapy with neratinib.Experimental Design: Mice with established ER+/HER2+ MDA-MB-361 tumors were treated with paclitaxel plus trastuzumab ± pertuzumab for 4 weeks, and then randomized to fulvestrant ± neratinib treatment. The benefit from neratinib was evaluated by performing gene expression analysis for 196 ER targets, ER transcriptional reporter assays, and cell-cycle analyses.Results:Mice receiving “extended adjuvant” therapy with fulvestrant/neratinib maintained a complete response, whereas those treated with fulvestrant relapsed rapidly. In three ER+/HER2+ cell lines (MDA-MB-361, BT-474, UACC-893) but not in ER+/HER2− MCF7 cells, treatment with neratinib induced ER reporter transcriptional activity, whereas treatment with fulvestrant resulted in increased HER2 and EGFR phosphorylation, suggesting compensatory reciprocal crosstalk between the ER and ERBB RTK pathways. ER transcriptional reporter assays, gene expression, and immunoblot analyses showed that treatment with neratinib/fulvestrant, but not fulvestrant, potently inhibited growth and downregulated ER reporter activity, P-AKT, P-ERK, and cyclin D1 levels. Finally, similar to neratinib, genetic and pharmacologic inactivation of cyclin D1 enhanced fulvestrant action against ER+/HER2+ breast cancer cells.Conclusions:These data suggest that ER blockade leads to reactivation of ERBB RTKs and thus extended ERBB blockade is necessary to achieve durable clinical outcomes in patients with ER+/HER2+ breast cancer.
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- 2019
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12. An ERBB1-3 Neutralizing Antibody Mixture With High Activity Against Drug-Resistant HER2+ Breast Cancers With ERBB Ligand Overexpression
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Monica V. Estrada, Melinda E. Sanders, Christian D. Young, Monica Red-Brewer, Michael Kragh, Katherine E. Hutchinson, Carlos L. Arteaga, Teresa C. Dugger, Mikkel Wandahl Pedersen, Brent N. Rexer, Paula Gonzalez Ericsson, Angel Guerrero-Zotano, Luis J. Schwarz, Johan Lantto, Ivan D Horak, Luigi Formisano, Schwarz, Lj, Hutchinson, Ke, Rexer, Bn, Estrada, Mv, Gonzalez Ericsson, Pi, Sanders, Me, Dugger, Tc, Formisano, L, Guerrero-Zotano, A, Red-Brewer, M, Young, Cd, Lantto, J, Pedersen, Mw, Kragh, M, Horak, Id, and Arteaga, Cl.
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0301 basic medicine ,Cancer Research ,Receptor, ErbB-3 ,Receptor, ErbB-2 ,Mice, Nude ,Antineoplastic Agents ,Breast Neoplasms ,Ado-Trastuzumab Emtansine ,Antibodies, Monoclonal, Humanized ,Ligands ,Lapatinib ,Mice ,03 medical and health sciences ,ErbB Receptors ,0302 clinical medicine ,ErbB ,Trastuzumab ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Maytansine ,Epidermal growth factor receptor ,skin and connective tissue diseases ,biology ,Cancer ,Articles ,medicine.disease ,Antibodies, Neutralizing ,Xenograft Model Antitumor Assays ,Molecular biology ,030104 developmental biology ,Oncology ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,Quinazolines ,Cancer research ,biology.protein ,Immunohistochemistry ,Female ,Pertuzumab ,medicine.drug - Abstract
BACKGROUND: Plasticity of the ERBB receptor network has been suggested to cause acquired resistance to anti–human epidermal growth factor receptor 2 (HER2) therapies. Thus, we studied whether a novel approach using an ERBB1-3-neutralizing antibody mixture can block these compensatory mechanisms of resistance. METHODS: HER2+ cell lines and xenografts (n ≥ 6 mice per group) were treated with the ERBB1-3 antibody mixture Pan-HER, trastuzumab/lapatinib (TL), trastuzumab/pertuzumab (TP), or T-DM1. Downregulation of ERBB receptors was assessed by immunoblot analysis and immunohistochemistry. Paired pre- and post-T-DM1 tumor biopsies from patients (n = 11) with HER2-amplified breast cancer were evaluated for HER2 and P-HER3 expression by immunohistochemistry and/or fluorescence in situ hybridization. ERBB ligands were measured by quantitative reverse transcription polymerase chain reaction. Drug-resistant cells were generated by chronic treatment with T-DM1. All statistical tests were two-sided. RESULTS: Treatment with Pan-HER inhibited growth and promoted degradation of ERBB1-3 receptors in a panel of HER2+ breast cancer cells. Compared with TL, TP, and T-DM1, Pan-HER induced a similar antitumor effect against established BT474 and HCC1954 tumors, but was superior to TL against MDA-361 xenografts (TL mean = 2026 mm(3), SD = 924 mm(3), vs Pan-HER mean = 565 mm(3), SD = 499 mm(3), P = .04). Pan-HER-treated BT474 xenografts did not recur after treatment discontinuation, whereas tumors treated with TL, TP, and T-DM1 did. Post-TP and post-T-DM1 recurrent tumors expressed higher levels of neuregulin-1 (NRG1), HER3 and P-HER3 (all P < .05). Higher levels of P-HER3 protein and NRG1 mRNA were also observed in HER2+ breast cancers progressing after T-DM1 and trastuzumab (NRG1 transcript fold change ± SD; pretreatment = 2, SD = 1.9, vs post-treatment = 11.4, SD = 10.3, P = .04). The HER3-neutralizing antibody LJM716 resensitized the drug-resistant cells to T-DM1, suggesting a causal association between the NRG1-HER3 axis and drug resistance. Finally, Pan-HER treatment inhibited growth of HR6 trastuzumab- and T-DM1-resistant xenografts. CONCLUSIONS: These data suggest that upregulation of a NRG1-HER3 axis can mediate escape from anti-HER2 therapies. Further, multitargeted antibody mixtures, such as Pan-HER, can simultaneously remove and/or block targeted ERBB receptor and ligands, thus representing an effective approach against drug-sensitive and -resistant HER2+ cancers.
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- 2017
13. A nationwide pilot study on breast cancer screening in Peru.
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Araujo JM, Gómez AC, Jongh WZ, Ausejo J, Córdova I, Schwarz LJ, Bretel D, Fajardo W, Saravia-Huarca LG, Barboza-Meca J, Morante Z, Guillén JR, Gómez H, Cárdenas NK, Hernández L, Melo W, Villarreal-Garza C, Caglevic C, Palacio C, García H, Mejía G, Flores C, Vallejos C, and Pinto JA
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Introduction: A high prevalence of advanced breast cancer (BC) is a common scenario in Latin America. In Peru, the frequency of BC at Stages III/IV is ≈50% despite implementation of a programme for breast cancer screening (BCS) along the country. We carried out a study to assess the feasibility and develop an instrument to evaluate the knowledge, barriers and perception about BCS in a nationwide pilot study in Peru among candidates for BCS., Methods: We conducted a systematic review of 2,558 reports indexed in PubMed, Scopus, Web of Science, Medline-Ovid and EMBASE, regarding to our study theme. In total, 111 were selected and a 51-items survey was developed (eight items about sociodemographic characteristics). Patients were recruited in public hospitals or private clinics, in rural and urban areas of nine departments of Peru., Results: We surveyed 488 women from: Lima (150), Cajamarca (93), Ica (59), Arequipa (56), Loreto (48), Ancash (38), Junín (15), Puerto Maldonado (15) and Huancavelica (14); 27.9% of them were from rural areas. The mean of age was 53.3 years (standard deviation ± 9.1). Regarding education level, 29.8% had primary, 33.2% secondary and 37.0% higher education. In total, 28.7% of women did not know the term 'mammogram' and 47.1% reported never receiving a BCS (36.9% from urban and 73.5% from rural population). In women that underwent BCS, only 67% knew it is for healthy women. In total, 54.1% of patients had low levels of knowledge about risk factors for BC (i.e. 87.5% of women respond that injuries in the breast produce cancer). Cultural, economic and geographic barriers were significantly associated with having a mammogram where 56.9% of participants considered a cost ≤ 7 USD as appropriate. Mammogram was perceived as too painful for 54.9% of women. In addition, women with a self-perception of low-risk for BC and a fatalistic perception of cancer were less likely to have a BCS., Conclusion: We found that it is feasible to conduct a large-scale study in Peru. The results of this pilot study highlight an urgent need of extensive education and awareness about BCS in Peru., Competing Interests: The authors declare that they have no conflicts of interest., (© the authors; licensee ecancermedicalscience.)
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- 2023
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14. Influence of Sex in the Molecular Characteristics and Outcomes of Malignant Tumors.
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Araujo JM, Rosas G, Belmar-López C, Raez LE, Rolfo CD, Schwarz LJ, Infante-Huaytalla U, Paez KJ, García LR, Alvarado H, Ramos FP, Delgado-Espinoza SS, Cardenas-Farfan JB, Cornejo M, Zanabria D, Colonio-Cossio C, Rojas-Jefferson M, and Pinto JA
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Background: Sex is frequently underestimated as a prognostic biomarker in cancer. In this study, we evaluated a large cohort of patients and public datasets to determine the influence of sex on clinical outcomes, mutational status, and activation of immune pathways in different types of cancer., Methods: A cohort of 13,619 Oncosalud-affiliated patients bearing sex-unrelated cancers was followed over a 20-year period. Hazard ratios (HRs) for death were estimated for female vs . male patients for each cancer type and then pooled in a meta-analysis to obtain an overall HR. In addition, the mutational status of the main actionable genes in melanoma (MEL), colorectal cancer (CRC), and lung cancer was compared between sexes. Finally, a gene set enrichment analysis (GSEA) of publicly available data was conducted, to assess differences in immune processes between sexes in MEL, gastric adenocarcinoma (GC), head and neck cancer (HNC), colon cancer (CC), liver cancer (LC), pancreatic cancer (PC), thyroid cancer (TC), and clear renal cell carcinoma (CCRCC)., Results: Overall, women had a decreased risk of death (HR = 0.73, CI95: 8%-42%), with improved overall survival (OS) in HNC, leukemia, lung cancer, lymphoma, MEL, multiple myeloma (MM), and non-melanoma skin cancer. Regarding the analysis of actionable mutations, only differences in EGFR alterations were observed (27.7% for men vs . 34.4% for women, p = 0.035). The number of differentially activated immune processes was higher in women with HNC, LC, CC, GC, MEL, PC, and TC and included cellular processes, responses to different stimuli, immune system development, immune response activation, multiorganism processes, and localization of immune cells. Only in CCRCC was a higher activation of immune pathways observed in men., Conclusions: The study shows an improved survival rate, increased activation of immune system pathways, and an enrichment of EGFR alterations in female patients of our cohort. Enhancement of the immune response in female cancer patients is a phenomenon that should be further explored to improve the efficacy of immunotherapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Araujo, Rosas, Belmar-López, Raez, Rolfo, Schwarz, Infante-Huaytalla, Paez, García, Alvarado, Ramos, Delgado-Espinoza, Cardenas-Farfan, Cornejo, Zanabria, Colonio-Cossio, Rojas-Jefferson and Pinto.)
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- 2021
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15. The Antioxidant and Anti-Inflammatory Properties of Rice Bran Phenolic Extracts.
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Saji N, Francis N, Schwarz LJ, Blanchard CL, and Santhakumar AB
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Oxidative stress and inflammation are known to be linked to the development of chronic inflammatory conditions, such as type 2 diabetes and cardiovascular disease. Dietary polyphenols have been demonstrated to contain potent bioactivity against specific inflammatory pathways. Rice bran (RB), a by-product generated during the rice milling process, is normally used in animal feed or discarded due to its rancidity. However, RB is known to be abundant in bioactive polyphenols including phenolic acids. This study investigates the antioxidant and anti-inflammatory effects of RB phenolic extracts (25, 50, 100, and 250 µg/mL) on RAW264.7 mouse macrophage cells stimulated with hydrogen peroxide and lipopolysaccharide. Biomarkers of oxidative stress and inflammation such as malondialdehyde (MDA), intracellular reactive oxygen species, nitric oxide and pro-inflammatory cytokines such as interleukin-6 (IL-6), monocyte chemoattractant protein 1 (MCP-1), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), interleukin-12, p70 (IL-12p70), and interferon-γ (IFN-γ) were measured in vitro. Treatment with RB extracts significantly decreased the production of MDA, intracellular reactive oxygen species, nitric oxide and pro-inflammatory cytokines (IL-6, IL-12p70, and IFN-γ) when compared to the control. It is proposed that RB phenolic extracts, via their metal chelating properties and free radical scavenging activity, target pathways of oxidative stress and inflammation resulting in the alleviation of vascular inflammatory mediators.
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- 2020
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16. Rice Bran Phenolic Extracts Modulate Insulin Secretion and Gene Expression Associated with β-Cell Function.
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Saji N, Francis N, Schwarz LJ, Blanchard CL, and Santhakumar AB
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- Animals, Cell Line, Tumor, Cell Survival drug effects, Gene Expression drug effects, Insulin metabolism, Insulin-Secreting Cells drug effects, Rats, Dietary Fiber, Insulin Secretion drug effects, Oryza, Phenols pharmacology, Plant Extracts pharmacology
- Abstract
Oxidative stress is known to modulate insulin secretion and initiate gene alterations resulting in impairment of β-cell function and type 2 diabetes mellitus (T2DM). Rice bran (RB) phenolic extracts contain bioactive properties that may target metabolic pathways associated with the pathogenesis of T2DM. This study aimed to examine the effect of stabilized RB phenolic extracts on the expression of genes associated with β-cell function such as glucose transporter 2 ( Glut2 ), pancreatic and duodenal homeobox 1 ( Pdx1 ), sirtuin 1 ( Sirt1 ), mitochondrial transcription factor A ( Tfam ), and insulin 1 ( Ins1 ) in addition to evaluating its impact on glucose-stimulated insulin secretion. It was observed that treatment with different concentrations of RB phenolic extracts (25-250 µg/mL) significantly increased the expression of Glut2 , Pdx1 , Sirt1, Tfam, and Ins1 genes and glucose-stimulated insulin secretion under both normal and high glucose conditions. RB phenolic extracts favourably modulated the expression of genes involved in β-cell dysfunction and insulin secretion via several mechanisms such as synergistic action of polyphenols targeting signalling molecules, decreasing free radical damage by its antioxidant activity, and stimulation of effectors or survival factors of insulin secretion.
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- 2020
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17. Parallel enrichment of polyphenols and phytosterols from Pinot noir grape seeds with molecularly imprinted polymers and analysis by capillary high-performance liquid chromatography electrospray ionisation tandem mass spectrometry.
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Hashim SNNS, Boysen RI, Yang Y, Schwarz LJ, Danylec B, and Hearn MTW
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- Chromatography, High Pressure Liquid, Hexanes chemistry, Seeds chemistry, Solvents chemistry, Spectrometry, Mass, Electrospray Ionization, Tandem Mass Spectrometry, Molecular Imprinting, Phytosterols chemistry, Phytosterols isolation & purification, Polymers chemical synthesis, Polyphenols chemistry, Polyphenols isolation & purification, Vitis chemistry
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This investigation describes an integrated workflow for the parallel extraction and recovery of polyphenols and phytosterols from Pinot noir grape seeds. Using (E)-resveratrol and stigmasterol as exemplars, the approach employs two different molecular imprinted polymers in tandem for the extraction of these compounds and their subsequent analysis by capillary high-performance liquid chromatography (capHPLC) interfaced with electrospray ionisation tandem mass spectrometry (ESI MS/MS). Information on the selectivity of the solid-phase extraction processes was obtained through analysis of the binding behaviour of (E)-resveratrol- and stigmasterol-imprinted polymers using structurally similar polyphenols or phytosterols with the extent of binding determined from the capHPLC-ion trap ESI MS/MS data. This study documents with Pinot noir grape seed extracts and optimised solid-phase extraction protocols that the (E)-resveratrol-templated MIP enabled a very high recovery (99%) of the health-beneficial polyphenol (E)-resveratrol with co-purification of procyanidin and catechin/epicatechin. Further, the stigmasteryl-3-O-methacrylate-templated polymer resulted in high recovery (96%) of the phytosterol stigmasterol with co-purification of campesteryl glycoside. The results also demonstrate that rapid and high-resolution capHPLC-ESI MS/MS methods can be used as part of the work flow for selectivity optimisation and monitoring of the performance of MIPs intended for use in the solid-phase extraction of bioactive molecules with nutraceutical properties from agricultural waste streams., (Copyright © 2019 Elsevier B.V. All rights reserved.)
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- 2020
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18. Rice Bran Derived Bioactive Compounds Modulate Risk Factors of Cardiovascular Disease and Type 2 Diabetes Mellitus: An Updated Review.
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Saji N, Francis N, Schwarz LJ, Blanchard CL, and Santhakumar AB
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- Animals, Functional Food, Humans, Polyphenols, Rats, Risk Factors, Cardiovascular Diseases diet therapy, Cardiovascular Diseases epidemiology, Cardiovascular Diseases prevention & control, Diabetes Mellitus, Type 2 diet therapy, Diabetes Mellitus, Type 2 epidemiology, Diabetes Mellitus, Type 2 prevention & control, Dietary Fiber, Oryza
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Cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) are two chronic diseases that have claimed more lives globally than any other disease. Dietary supplementation of functional foods containing bioactive compounds is recognised to result in improvements in free-radical-mediated oxidative stress. Emerging evidence indicates that bioactive compounds derived from rice bran (RB) have therapeutic potential against cellular oxidative stress. This review aims to describe the mechanistic pathways behind CVD and T2DM development and the therapeutic potential of polyphenols derived from RB against these chronic diseases.
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- 2019
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19. Rice Bran Phenolic Compounds Regulate Genes Associated with Antioxidant and Anti-Inflammatory Activity in Human Umbilical Vein Endothelial Cells with Induced Oxidative Stress.
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Saji N, Francis N, Blanchard CL, Schwarz LJ, and Santhakumar AB
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- Human Umbilical Vein Endothelial Cells cytology, Humans, Plant Extracts chemistry, Anti-Inflammatory Agents metabolism, Antioxidants metabolism, Gene Expression Regulation drug effects, Human Umbilical Vein Endothelial Cells metabolism, Oryza chemistry, Oxidative Stress drug effects, Plant Extracts pharmacology
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Oxidative stress, inflammation and endothelial dysfunction are associated with the development of cardiovascular and metabolic diseases. Phenolic extracts derived from rice bran (RB) are recognised to have antioxidant and anti-inflammatory potential. However, the underlying mechanisms remain unknown. Therefore, this study aimed to evaluate the ability of RB-derived phenolic extracts to modulate genes associated with antioxidant and anti-inflammatory pathways in human umbilical vein endothelial cells (HUVECs) under induced oxidative stress conditions. HUVECs under oxidative stress were treated with varying concentrations of RB phenolic extracts (25-250 µg/mL). Using quantitative real-time polymerase chain reaction, the expression of candidate genes that regulate antioxidant and anti-inflammatory pathways were determined. This included nuclear factor erythroid 2-related factor 2 ( Nrf2 ), nicotinamide adenine dinucleotide phosphate: quinone oxidoreductase 1 ( NQO1 ), heme oxygenase 1 ( HO1 ), nicotinamide adenine dinucleotide phosphate oxidase 4 ( NOX4 ), intercellular adhesion molecule 1 ( ICAM1 ), endothelial nitric oxide synthase ( eNOS ), ectonucleoside triphosphate diphosphohydrolase 1 ( CD39 ) and ecto-5'-nucleotidase ( CD73 ). Phenolic extracts derived from RB down-regulated the expression of four genes, ICAM1 , CD39 , CD73 and NOX4 and up-regulated the expression of another four genes, Nrf2 , NQO1 , HO1 and eNOS , indicating an antioxidant/ anti-inflammatory effect for RB against endothelial dysfunction.
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- 2019
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20. Recent Advances in Research on Hoarding.
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Davidson EJ, Dozier ME, Pittman JOE, Mayes TL, Blanco BH, Gault JD, Schwarz LJ, and Ayers CR
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- Cognitive Behavioral Therapy, Hoarding psychology, Hoarding therapy, Humans, Object Attachment, Psychotherapy, Group, Risk Factors, Behavioral Research, Hoarding Disorder psychology, Hoarding Disorder therapy
- Abstract
Purpose of Review: The purpose of the following paper is to review recent literature trends and findings in hoarding disorder (HD). Our goal is to highlight recent research on etiology, associated features, and empirically based treatments., Recent Findings: Recent literature has added support for cognitive differences as a risk factor for HD; however, there is evidence that individuals with HD may overestimate their level of cognitive impairment. Several associated features have been highlighted in recent studies, including emotion regulation, intolerance of uncertainty and distress intolerance, and attachment. Finally, several psychotherapeutic treatments for hoarding have been recently validated, including group-based therapy and treatments using the cognitive-behavioral model. Although recent research demonstrates that hoarding can be effectively treated with available psychotherapeutic modalities, the effectiveness of current treatments is not as robust as that for other psychiatric disorders and more work is needed in treatment precision.
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- 2019
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21. Patterns of Mutation Enrichment in Metastatic Triple-Negative Breast Cancer.
- Author
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Saravia CH, Flores C, Schwarz LJ, Bravo L, Zavaleta J, Araujo J, Neciosup S, and Pinto JA
- Abstract
Background: Triple-negative breast cancer (TNBC) is a heterogeneous disease with aggressive biology and complex tumor evolution. Our purpose was to identify enrichment patterns of genomic alterations in metastatic triple-negative breast cancer (mTNBC)., Methods: Genomic data were retrieved (mutations and copy number variations) from 550 primary TNBC tumors from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas (TCGA) data sets and 58 mTNBC tumors from "Mutational Profile of Metastatic Breast Cancers" and "The Metastatic Breast Cancer Project." Statistical analysis of microarray data between primary and metastatic tumors was performed using a chi-square test, and the percentage of mutation enrichment in mTNBC cases was estimated. P -values were adjusted for multiple testing with Benjamini-Hochberg method with a false-discovery rate (FDR) <.05. In addition, we identified dominant hallmarks of cancer in mTNBC., Results: Seven genes with mutations were enriched in mTNBC after correcting for multiple testing. These included TTN, HMCN1, RELN, PKHD1L1, DMD, FRAS1 , and RYR3 . Only RPS6KB2 amplification was statistically significant in mTNBC; on the contrary, deletion of the genes TET1, RHOA, EPHA5, SET, KCNJ5, ABCG4, NKX3-1, SDHB, IGF2 , and BRCA1 were the most frequent. The molecular alterations related to the hallmark of "genetic instability and mutation" were predominant in mTNBC. Interestingly, the hallmark of "activating immune destruction" was the least represented in mTNBC., Conclusion: Despite the study limitations, we identified recurrent patterns of genomic alterations with potential contribution to tumor evolution. Deletions were the aberrations more commonly found in mTNBC. Several molecular alterations are potentially targetable., Competing Interests: Declaration of Conflicting Interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2019
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22. Aberrant FGFR signaling mediates resistance to CDK4/6 inhibitors in ER+ breast cancer.
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Formisano L, Lu Y, Servetto A, Hanker AB, Jansen VM, Bauer JA, Sudhan DR, Guerrero-Zotano AL, Croessmann S, Guo Y, Ericsson PG, Lee KM, Nixon MJ, Schwarz LJ, Sanders ME, Dugger TC, Cruz MR, Behdad A, Cristofanilli M, Bardia A, O'Shaughnessy J, Nagy RJ, Lanman RB, Solovieff N, He W, Miller M, Su F, Shyr Y, Mayer IA, Balko JM, and Arteaga CL
- Subjects
- Aminopyridines administration & dosage, Aminopyridines pharmacology, Animals, Antineoplastic Agents, Hormonal administration & dosage, Antineoplastic Agents, Hormonal pharmacology, Breast Neoplasms genetics, Breast Neoplasms metabolism, Cyclin D1 metabolism, Cyclin-Dependent Kinase 4 antagonists & inhibitors, Cyclin-Dependent Kinase 6 antagonists & inhibitors, Drug Resistance, Neoplasm drug effects, Female, Fulvestrant administration & dosage, Fulvestrant pharmacology, High-Throughput Nucleotide Sequencing, Humans, MCF-7 Cells, Mice, Mutation, Naphthalenes pharmacology, Piperazines pharmacology, Progression-Free Survival, Proportional Hazards Models, Protein Kinase Inhibitors administration & dosage, Protein Kinase Inhibitors pharmacology, Purines administration & dosage, Purines pharmacology, Pyrazoles pharmacology, Pyridines pharmacology, Quinolines pharmacology, Quinoxalines pharmacology, Receptor, Fibroblast Growth Factor, Type 1 antagonists & inhibitors, Receptor, Fibroblast Growth Factor, Type 2 antagonists & inhibitors, Receptors, Estrogen metabolism, Signal Transduction, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Breast Neoplasms drug therapy, Circulating Tumor DNA genetics, Drug Resistance, Neoplasm genetics, Receptor, Fibroblast Growth Factor, Type 1 genetics, Receptor, Fibroblast Growth Factor, Type 2 genetics
- Abstract
Using an ORF kinome screen in MCF-7 cells treated with the CDK4/6 inhibitor ribociclib plus fulvestrant, we identified FGFR1 as a mechanism of drug resistance. FGFR1-amplified/ER+ breast cancer cells and MCF-7 cells transduced with FGFR1 were resistant to fulvestrant ± ribociclib or palbociclib. This resistance was abrogated by treatment with the FGFR tyrosine kinase inhibitor (TKI) lucitanib. Addition of the FGFR TKI erdafitinib to palbociclib/fulvestrant induced complete responses of FGFR1-amplified/ER+ patient-derived-xenografts. Next generation sequencing of circulating tumor DNA (ctDNA) in 34 patients after progression on CDK4/6 inhibitors identified FGFR1/2 amplification or activating mutations in 14/34 (41%) post-progression specimens. Finally, ctDNA from patients enrolled in MONALEESA-2, the registration trial of ribociclib, showed that patients with FGFR1 amplification exhibited a shorter progression-free survival compared to patients with wild type FGFR1. Thus, we propose breast cancers with FGFR pathway alterations should be considered for trials using combinations of ER, CDK4/6 and FGFR antagonists.
- Published
- 2019
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23. Correction: Association of FGFR1 with ERα Maintains Ligand-Independent ER Transcription and Mediates Resistance to Estrogen Deprivation in ER + Breast Cancer.
- Author
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Formisano L, Stauffer KM, Young CD, Bhola NE, Guerrero-Zotano AL, Jansen VM, Estrada MM, Hutchinson KE, Giltnane JM, Schwarz LJ, Lu Y, Balko JM, Deas O, Cairo S, Judde JG, Mayer IA, Sanders M, Dugger TC, Bianco R, Stricker T, and Arteaga CL
- Published
- 2019
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24. Correction: ER + Breast Cancers Resistant to Prolonged Neoadjuvant Letrozole Exhibit an E2F4 Transcriptional Program Sensitive to CDK4/6 Inhibitors.
- Author
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Guerrero-Zotano AL, Stricker TP, Formisano L, Hutchinson KE, Stover DG, Lee KM, Schwarz LJ, Giltnane JM, Estrada MV, Jansen VM, Servetto A, Gavilá J, Perez-Fidalgo JA, Lluch A, Llombart-Cussac A, Bayar MA, Michiels S, André F, Arnedos M, Guillem V, Ruiz-Simon A, and Arteaga CL
- Published
- 2019
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25. Helicobacter pylori: History and facts in Peru.
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Tirado-Hurtado I, Carlos C, Lancho L, Alfaro A, Ponce R, Schwarz LJ, Torres L, Ayudant M, Pinto JA, and Fajardo W
- Subjects
- Helicobacter Infections complications, Helicobacter Infections virology, History, 20th Century, History, 21st Century, Humans, Incidence, Peru epidemiology, Stomach Neoplasms etiology, Stomach Neoplasms prevention & control, Helicobacter Infections history, Helicobacter pylori isolation & purification, Stomach Neoplasms epidemiology
- Abstract
Helicobacter pylori (H. pylori) is a cosmopolite bacteria and the main responsible for the high burden of gastric cancer in developing countries, such as Peru. In this review, we describe some historical facts in the H. Pylori discovery, the first researches of this bacterium in Peru, as well as its epidemiology, clinical characteristics, diagnosis, treatments, and outcomes. Our literature and review of real-life data suggest that several efforts should be conducted in our country to deal with antibiotic-resistance and lack of adherence to treatment in order to reduce our incidence of gastric cancer., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
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26. Precision medicine for locally advanced breast cancer: frontiers and challenges in Latin America.
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Pinto JA, Saravia CH, Flores C, Araujo JM, Martínez D, Schwarz LJ, Casas A, Bravo L, Zavaleta J, Chuima B, Alvarado H, Fujita R, and Gómez HL
- Abstract
Advances in high-throughput technologies and their involvement in the 'omics' of cancer have made possible the identification of hundreds of biomarkers and the development of predictive and prognostic platforms that model the management of cancer from evidence-based medicine to precision medicine. Latin America (LATAM) is a region characterised by fragmented healthcare, high rates of poverty and disparities to access to a basic standard of care not only for cancer but also for other complex diseases. Patients from the public setting cannot afford targeted therapy, the facilities offering genomic platforms are scarce and the use of high-precision radiotherapy is limited to few facilities. Despite the fact that LATAM oncologists are well-trained in the use of genomic platforms and constantly participate in genomic projects, a medical practice based in precision oncology is a great challenge and frequently limited to private practice. In breast cancer, we are waiting for the results of large basket trials to incorporate the detection of actionable mutations to select targeted treatments, in a similar way to the management of lung cancer. On the other hand and paradoxically, in the 'one fit is not for all' era, clinical and genomic studies continue grouping our patients under the single label 'Latin American' or 'Hispanic' despite the different ancestries and genomic backgrounds seen in the region. More regional cancer genomic initiatives and public availability of this data are needed in order to develop more precise oncology in locally advanced breast cancer.
- Published
- 2019
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27. Extended Adjuvant Therapy with Neratinib Plus Fulvestrant Blocks ER/HER2 Crosstalk and Maintains Complete Responses of ER + /HER2 + Breast Cancers: Implications to the ExteNET Trial.
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Sudhan DR, Schwarz LJ, Guerrero-Zotano A, Formisano L, Nixon MJ, Croessmann S, González Ericsson PI, Sanders M, Balko JM, Avogadri-Connors F, Cutler RE, Lalani AS, Bryce R, Auerbach A, and Arteaga CL
- Subjects
- Animals, Antineoplastic Combined Chemotherapy Protocols adverse effects, Biomarkers, Tumor, Breast Neoplasms pathology, Cell Line, Tumor, Chemotherapy, Adjuvant, Disease Models, Animal, Female, Fulvestrant administration & dosage, Humans, Immunohistochemistry, Mice, Quinolines administration & dosage, Treatment Outcome, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Breast Neoplasms drug therapy, Breast Neoplasms metabolism, Receptor, ErbB-2 metabolism, Receptors, Estrogen metabolism
- Abstract
Purpose: The phase III ExteNET trial showed improved invasive disease-free survival in patients with HER2
+ breast cancer treated with neratinib versus placebo after trastuzumab-based adjuvant therapy. The benefit from neratinib appeared to be greater in patients with ER+ /HER2+ tumors. We thus sought to discover mechanisms that may explain the benefit from extended adjuvant therapy with neratinib. Experimental Design: Mice with established ER+ /HER2+ MDA-MB-361 tumors were treated with paclitaxel plus trastuzumab ± pertuzumab for 4 weeks, and then randomized to fulvestrant ± neratinib treatment. The benefit from neratinib was evaluated by performing gene expression analysis for 196 ER targets, ER transcriptional reporter assays, and cell-cycle analyses., Results: Mice receiving "extended adjuvant" therapy with fulvestrant/neratinib maintained a complete response, whereas those treated with fulvestrant relapsed rapidly. In three ER+ /HER2+ cell lines (MDA-MB-361, BT-474, UACC-893) but not in ER+ /HER2- MCF7 cells, treatment with neratinib induced ER reporter transcriptional activity, whereas treatment with fulvestrant resulted in increased HER2 and EGFR phosphorylation, suggesting compensatory reciprocal crosstalk between the ER and ERBB RTK pathways. ER transcriptional reporter assays, gene expression, and immunoblot analyses showed that treatment with neratinib/fulvestrant, but not fulvestrant, potently inhibited growth and downregulated ER reporter activity, P-AKT, P-ERK, and cyclin D1 levels. Finally, similar to neratinib, genetic and pharmacologic inactivation of cyclin D1 enhanced fulvestrant action against ER+ /HER2+ breast cancer cells., Conclusions: These data suggest that ER blockade leads to reactivation of ERBB RTKs and thus extended ERBB blockade is necessary to achieve durable clinical outcomes in patients with ER+ /HER2+ breast cancer., (©2018 American Association for Cancer Research.)- Published
- 2019
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28. A GC-MS untargeted metabolomics approach for the classification of chemical differences in grape juices based on fungal pathogen.
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Schueuermann C, Steel CC, Blackman JW, Clark AC, Schwarz LJ, Moraga J, Collado IG, and Schmidtke LM
- Subjects
- Botrytis, Fruit, Fruit and Vegetable Juices analysis, Fruit and Vegetable Juices microbiology, Gas Chromatography-Mass Spectrometry, Metabolomics, Vitis chemistry, Vitis microbiology
- Abstract
Fungal bunch rot of grapes leads to production of detrimental flavour compounds, some of which are well characterised but others remain unidentified. The current study uses an untargeted metabolomics approach to classify volatile profiles of grape juices based on the presence of different fungal pathogens. Individual grape berries were inoculated with Botrytis cinerea, Penicillium expansum, Aspergillus niger or A. carbonarius. Grape bunches were inoculated and blended with healthy fruit, to provide 10% (w/w) infected juice. Juices from the above sample batches were analysed by GC/MS. PLS-DA of the normalised summed mass ions indicated sample classification according to pathogen. Compounds identified from those mass ion matrices that had high discriminative value for classification included 1,5-dimethylnaphthalene and several unidentified sesquiterpenes that were relatively higher in B. cinerea infected samples. A. niger and A. carbonarius samples were relatively higher in 2-(4-hexyl-2,5-dioxo-2,5-dihydrofuran-3-yl)acetic acid, while P. expansum samples were higher in γ-nonalactone and m-cresol., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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29. ER + Breast Cancers Resistant to Prolonged Neoadjuvant Letrozole Exhibit an E2F4 Transcriptional Program Sensitive to CDK4/6 Inhibitors.
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Guerrero-Zotano AL, Stricker TP, Formisano L, Hutchinson KE, Stover DG, Lee KM, Schwarz LJ, Giltnane JM, Estrada MV, Jansen VM, Servetto A, Gavilá J, Perez-Fidalgo JA, Lluch A, Llombart-Cussac A, Bayar MA, Michiels S, André F, Arnedos M, Guillem V, Ruiz-Simon A, and Arteaga CL
- Subjects
- Aged, Aged, 80 and over, Aromatase Inhibitors therapeutic use, Biomarkers, Tumor, Breast Neoplasms metabolism, Cell Line, Tumor, Cell Proliferation, Computational Biology methods, E2F4 Transcription Factor metabolism, Female, Gene Expression Profiling, Humans, Letrozole therapeutic use, Middle Aged, Mutation, Protein Kinase Inhibitors pharmacology, Receptors, Estrogen metabolism, Retreatment, Transcriptome, Breast Neoplasms drug therapy, Breast Neoplasms genetics, Drug Resistance, Neoplasm drug effects, Drug Resistance, Neoplasm genetics, E2F4 Transcription Factor genetics, Protein Kinase Inhibitors therapeutic use, Receptors, Estrogen genetics
- Abstract
Purpose: This study aimed to identify biomarkers of resistance to endocrine therapy in estrogen receptor-positive (ER
+ ) breast cancers treated with prolonged neoadjuvant letrozole. Experimental Design: We performed targeted DNA and RNA sequencing in 68 ER+ breast cancers from patients treated with preoperative letrozole (median, 7 months). Results: Twenty-four tumors (35%) exhibited a PEPI score ≥4 and/or recurred after a median of 58 months and were considered endocrine resistant. Integration of the 47 most upregulated genes (log FC > 1, FDR < 0.03) in letrozole-resistant tumors with transcription-binding data showed significant overlap with 20 E2F4-regulated genes ( P = 2.56E-15). In patients treated with the CDK4/6 inhibitor palbociclib before surgery, treatment significantly decreased expression of 24 of the 47 most upregulated genes in letrozole-resistant tumors, including 18 of the 20 E2F4 target genes. In long-term estrogen-deprived ER+ breast cancer cells, palbociclib also downregulated all 20 E2F4 target genes and P-RB levels, whereas the ER downregulator fulvestrant or paclitaxel only partially suppressed expression of this set of genes and had no effect on P-RB. Finally, an E2F4 activation signature was strongly associated with resistance to aromatase inhibitors in the ACOSOG Z1031B neoadjuvant trial and with an increased risk of relapse in adjuvant-treated ER+ tumors in METABRIC. Conclusions: In tumors resistant to prolonged neoadjuvant letrozole, we identified a gene expression signature of E2F4 target activation. CDK4/6 inhibition suppressed E2F4 target gene expression in estrogen-deprived ER+ breast cancer cells and in patients' ER+ tumors, suggesting a potential benefit of adjuvant CDK4/6 inhibitors in patients with ER+ breast cancer who fail to respond to preoperative estrogen deprivation. Clin Cancer Res; 24(11); 2517-29. ©2018 AACR ., (©2018 American Association for Cancer Research.)- Published
- 2018
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30. An ERBB1-3 Neutralizing Antibody Mixture With High Activity Against Drug-Resistant HER2+ Breast Cancers With ERBB Ligand Overexpression.
- Author
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Schwarz LJ, Hutchinson KE, Rexer BN, Estrada MV, Gonzalez Ericsson PI, Sanders ME, Dugger TC, Formisano L, Guerrero-Zotano A, Red-Brewer M, Young CD, Lantto J, Pedersen MW, Kragh M, Horak ID, and Arteaga CL
- Subjects
- Ado-Trastuzumab Emtansine, Animals, Antibodies, Monoclonal, Humanized therapeutic use, Breast Neoplasms chemistry, Cell Line, Tumor, Drug Resistance, Neoplasm, ErbB Receptors antagonists & inhibitors, Female, Humans, Lapatinib, Ligands, Maytansine analogs & derivatives, Maytansine therapeutic use, Mice, Mice, Nude, Quinazolines therapeutic use, Receptor, ErbB-2 antagonists & inhibitors, Receptor, ErbB-3 antagonists & inhibitors, Trastuzumab therapeutic use, Xenograft Model Antitumor Assays, Antibodies, Neutralizing therapeutic use, Antineoplastic Agents therapeutic use, Breast Neoplasms drug therapy
- Abstract
Background: Plasticity of the ERBB receptor network has been suggested to cause acquired resistance to anti-human epidermal growth factor receptor 2 (HER2) therapies. Thus, we studied whether a novel approach using an ERBB1-3-neutralizing antibody mixture can block these compensatory mechanisms of resistance., Methods: HER2+ cell lines and xenografts (n ≥ 6 mice per group) were treated with the ERBB1-3 antibody mixture Pan-HER, trastuzumab/lapatinib (TL), trastuzumab/pertuzumab (TP), or T-DM1. Downregulation of ERBB receptors was assessed by immunoblot analysis and immunohistochemistry. Paired pre- and post-T-DM1 tumor biopsies from patients (n = 11) with HER2-amplified breast cancer were evaluated for HER2 and P-HER3 expression by immunohistochemistry and/or fluorescence in situ hybridization. ERBB ligands were measured by quantitative reverse transcription polymerase chain reaction. Drug-resistant cells were generated by chronic treatment with T-DM1. All statistical tests were two-sided., Results: Treatment with Pan-HER inhibited growth and promoted degradation of ERBB1-3 receptors in a panel of HER2+ breast cancer cells. Compared with TL, TP, and T-DM1, Pan-HER induced a similar antitumor effect against established BT474 and HCC1954 tumors, but was superior to TL against MDA-361 xenografts (TL mean = 2026 mm 3 , SD = 924 mm 3 , vs Pan-HER mean = 565 mm 3 , SD = 499 mm 3 , P = .04). Pan-HER-treated BT474 xenografts did not recur after treatment discontinuation, whereas tumors treated with TL, TP, and T-DM1 did. Post-TP and post-T-DM1 recurrent tumors expressed higher levels of neuregulin-1 (NRG1), HER3 and P-HER3 (all P < .05). Higher levels of P-HER3 protein and NRG1 mRNA were also observed in HER2+ breast cancers progressing after T-DM1 and trastuzumab (NRG1 transcript fold change ± SD; pretreatment = 2, SD = 1.9, vs post-treatment = 11.4, SD = 10.3, P = .04). The HER3-neutralizing antibody LJM716 resensitized the drug-resistant cells to T-DM1, suggesting a causal association between the NRG1-HER3 axis and drug resistance. Finally, Pan-HER treatment inhibited growth of HR6 trastuzumab- and T-DM1-resistant xenografts., Conclusions: These data suggest that upregulation of a NRG1-HER3 axis can mediate escape from anti-HER2 therapies. Further, multitargeted antibody mixtures, such as Pan-HER, can simultaneously remove and/or block targeted ERBB receptor and ligands, thus representing an effective approach against drug-sensitive and -resistant HER2+ cancers., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2017
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31. Association of FGFR1 with ERα Maintains Ligand-Independent ER Transcription and Mediates Resistance to Estrogen Deprivation in ER + Breast Cancer.
- Author
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Formisano L, Stauffer KM, Young CD, Bhola NE, Guerrero-Zotano AL, Jansen VM, Estrada MM, Hutchinson KE, Giltnane JM, Schwarz LJ, Lu Y, Balko JM, Deas O, Cairo S, Judde JG, Mayer IA, Sanders M, Dugger TC, Bianco R, Stricker T, and Arteaga CL
- Subjects
- Animals, Breast Neoplasms drug therapy, Breast Neoplasms pathology, Cell Line, Tumor, Disease Models, Animal, Estrogen Receptor Modulators pharmacology, Estrogen Receptor alpha antagonists & inhibitors, Female, Fibroblast Growth Factors genetics, Fibroblast Growth Factors metabolism, Gene Amplification, Gene Expression Regulation, Neoplastic, Humans, Mice, Molecular Targeted Therapy, Neoplasm Staging, Protein Kinase Inhibitors pharmacology, Protein Transport, Receptor, Fibroblast Growth Factor, Type 1 antagonists & inhibitors, Receptor, Fibroblast Growth Factor, Type 1 genetics, Signal Transduction drug effects, Breast Neoplasms genetics, Breast Neoplasms metabolism, Drug Resistance, Neoplasm genetics, Estrogen Receptor alpha genetics, Estrogen Receptor alpha metabolism, Receptor, Fibroblast Growth Factor, Type 1 metabolism, Transcription, Genetic
- Abstract
Purpose: FGFR1 amplification occurs in approximately 15% of estrogen receptor-positive (ER
+ ) human breast cancers. We investigated mechanisms by which FGFR1 amplification confers antiestrogen resistance to ER+ breast cancer. Experimental Design: ER+ tumors from patients treated with letrozole before surgery were subjected to Ki67 IHC, FGFR1 FISH, and RNA sequencing (RNA-seq). ER+ / FGFR1 -amplified breast cancer cells, and patient-derived xenografts (PDX) were treated with FGFR1 siRNA or the FGFR tyrosine kinase inhibitor lucitanib. Endpoints were cell/xenograft growth, FGFR1/ERα association by coimmunoprecipitation and proximity ligation, ER genomic activity by ChIP sequencing, and gene expression by RT-PCR. Results: ER+ / FGFR1 -amplified tumors in patients treated with letrozole maintained cell proliferation (Ki67). Estrogen deprivation increased total and nuclear FGFR1 and FGF ligands expression in ER+ / FGFR1- amplified primary tumors and breast cancer cells. In estrogen-free conditions, FGFR1 associated with ERα in tumor cell nuclei and regulated the transcription of ER-dependent genes. This association was inhibited by a kinase-dead FGFR1 mutant and by treatment with lucitanib. ChIP-seq analysis of estrogen-deprived ER+ / FGFR1 -amplified cells showed binding of FGFR1 and ERα to DNA. Treatment with fulvestrant and/or lucitanib reduced FGFR1 and ERα binding to DNA. RNA-seq data from FGFR1 -amplified patients' tumors treated with letrozole showed enrichment of estrogen response and E2F target genes. Finally, growth of ER+ / FGFR1- amplified cells and PDXs was more potently inhibited by fulvestrant and lucitanib combined than each drug alone. Conclusion s : These data suggest the ERα pathway remains active in estrogen-deprived ER+ / FGFR1 -amplified breast cancers. Therefore, these tumors are endocrine resistant and should be candidates for treatment with combinations of ER and FGFR antagonists. Clin Cancer Res; 23(20); 6138-50. ©2017 AACR ., (©2017 American Association for Cancer Research.)- Published
- 2017
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32. Molecularly imprinted polymer membranes and thin films for the separation and sensing of biomacromolecules.
- Author
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Boysen RI, Schwarz LJ, Nicolau DV, and Hearn MT
- Subjects
- Membranes, Artificial, Biosensing Techniques, Chemistry Techniques, Analytical instrumentation, Macromolecular Substances analysis, Macromolecular Substances isolation & purification, Polymers chemical synthesis
- Abstract
This review describes recent advances associated with the development of surface imprinting methods for the synthesis of polymeric membranes and thin films, which possess the capability to selectively and specifically recognize biomacromolecules, such as proteins and single- and double-stranded DNA, employing "epitope" or "whole molecule" approaches. Synthetic procedures to create different molecularly imprinted polymer membranes or thin films are discussed, including grafting/in situ polymerization, drop-, dip-, or spin-coating procedures, electropolymerization as well as micro-contact or stamp lithography imprinting methods. Highly sensitive techniques for surface characterization and analyte detection are described, encompassing luminescence and fluorescence spectroscopy, X-ray photoelectron spectroscopy, FTIR spectroscopy, surface-enhanced Raman spectroscopy, atomic force microscopy, quartz crystal microbalance analysis, cyclic voltammetry, and surface plasmon resonance. These developments are providing new avenues to produce bioelectronic sensors and new ways to explore through advanced separation science procedures complex phenomena associated with the origins of biorecognition in nature., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2017
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33. Selectivity mapping of the binding sites of (E)-resveratrol imprinted polymers using structurally diverse polyphenolic compounds present in Pinot noir grape skins.
- Author
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Hashim SNNS, Schwarz LJ, Danylec B, Potdar MK, Boysen RI, and Hearn MTW
- Subjects
- Binding Sites, Chromatography, High Pressure Liquid, Molecular Imprinting, Porosity, Resveratrol, Spectrometry, Mass, Electrospray Ionization, Surface Properties, Tandem Mass Spectrometry, Fruit chemistry, Plant Extracts chemistry, Polymers chemistry, Polyphenols analysis, Stilbenes chemistry, Vitis
- Abstract
This investigation describes a general procedure for the selectivity mapping of molecularly imprinted polymers, using (E)-resveratrol-imprinted polymers as the exemplar, and polyphenolic compounds present in Pinot noir grape skin extracts as the test compounds. The procedure is based on the analysis of samples generated before and after solid-phase extraction of (E)-resveratrol and other polyphenols contained within the Pinot noir grape skins using (E)-resveratrol-imprinted polymers. Capillary reversed-phase high-performance liquid chromatography (RP-HPLC) and electrospray ionisation tandem mass spectrometry (ESI MS/MS) was then employed for compound analysis and identification. Under optimised solid-phase extraction conditions, the (E)-resveratrol-imprinted polymer showed high binding affinity and selectivity towards (E)-resveratrol, whilst no resveratrol was bound by the corresponding non-imprinted polymer. In addition, quercetin-3-O-glucuronide and a dimer of catechin-methyl-5-furfuraldehyde, which share some structural features with (E)-resveratrol, were also bound by the (E)-resveratrol-imprinted polymer. Polyphenols that were non-specifically retained by both the imprinted and non-imprinted polymer were (+)-catechin, a B-type procyanidin and (-)-epicatechin. The compounds that did not bind to the (E)-resveratrol molecularly imprinted polymer had at least one of the following molecular characteristics in comparison to the (E)-resveratrol template: (i) different spatial arrangements of their phenolic hydroxyl groups, (ii) less than three or more than four phenolic hydroxyl groups, or (iii) contained a bulky substituent moiety. The results show that capillary RP-HPLC in conjunction with ESI MS/MS represent very useful techniques for mapping the selectivity of the binding sites of imprinted polymer. Moreover, this procedure permits performance monitoring of the characteristics of molecularly imprinted polymers intended for solid-phase extraction of bioactive and nutraceutical molecules from diverse agricultural waste sources., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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34. Recovery of ergosterol from the medicinal mushroom, Ganoderma tsugae var. Janniae, with a molecularly imprinted polymer derived from a cleavable monomer-template composite.
- Author
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Hashim SN, Schwarz LJ, Danylec B, Mitri K, Yang Y, Boysen RI, and Hearn MT
- Subjects
- Acetonitriles chemistry, Methacrylates chemistry, Molecular Imprinting, Solvents chemistry, Water chemistry, Chemistry Techniques, Analytical methods, Ergosterol isolation & purification, Ganoderma chemistry, Polymers chemistry, Solid Phase Extraction
- Abstract
A semi-covalent imprinting strategy has been developed for the synthesis of molecularly-imprinted polymers specific for the fungal sterol, ergosterol, a biological precursor of vitamin D
2 . This imprinting approach involved a novel post-synthesis cleavable monomer-template composite, namely ergosteryl methacrylate, and resulted in the formation of an imprinted polymer that selectively and efficiently recognized ergosterol through non-covalent interactions. The derived molecularly-imprinted polymer and the corresponding non-imprinted polymer were systematically evaluated for their selectivity towards ergosterol via static and dynamic binding studies using various ergosteryl esters (e.g. ergosteryl-cinnamate, -ferulate, -coumarate, -ferulate acetate and -acetate, respectively) as competitors. Moreover, the binding capacity of the molecularly imprinted polymer for ergosterol was enhanced when the sample loading conditions involved the use of partially aqueous solvent mixtures, such as acetonitrile/water (9:1 (v/v) or 8:2 (v/v)). These attributes were exploited in a solid-phase extraction format, whereby ergosterol was obtained with excellent recoveries from an extract of the fruiting body powder of the medicinal fungus Ganoderma tsugae var. Janniae., (Copyright © 2016 Elsevier B.V. All rights reserved.)- Published
- 2016
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35. Maybe we don't know JAK?
- Author
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Schwarz LJ and Balko JM
- Abstract
The cornerstone for precision medicine is the development of robust biomarkers that reflect molecular phenotypes and therapeutic vulnerabilities in disease. We recently described Janus kinase-2 (JAK2)-specific inhibition as a therapeutic opportunity in triple negative breast cancers with 9p24 amplification. Here, we comment on this work and discuss the challenges of targeting this amplicon.
- Published
- 2016
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36. Triple-negative breast cancers with amplification of JAK2 at the 9p24 locus demonstrate JAK2-specific dependence.
- Author
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Balko JM, Schwarz LJ, Luo N, Estrada MV, Giltnane JM, Dávila-González D, Wang K, Sánchez V, Dean PT, Combs SE, Hicks D, Pinto JA, Landis MD, Doimi FD, Yelensky R, Miller VA, Stephens PJ, Rimm DL, Gómez H, Chang JC, Sanders ME, Cook RS, and Arteaga CL
- Subjects
- Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Cell Line, Tumor, Cell Proliferation drug effects, Cohort Studies, Female, Gene Knockdown Techniques, Humans, Middle Aged, STAT3 Transcription Factor metabolism, STAT6 Transcription Factor metabolism, Signal Transduction drug effects, Spheroids, Cellular drug effects, Spheroids, Cellular pathology, Triple Negative Breast Neoplasms drug therapy, Triple Negative Breast Neoplasms pathology, Chromosomes, Human, Pair 9 genetics, Gene Amplification, Genetic Loci, Janus Kinase 2 genetics, Triple Negative Breast Neoplasms enzymology, Triple Negative Breast Neoplasms genetics
- Abstract
Amplifications at 9p24 have been identified in breast cancer and other malignancies, but the genes within this locus causally associated with oncogenicity or tumor progression remain unclear. Targeted next-generation sequencing of postchemotherapy triple-negative breast cancers (TNBCs) identified a group of 9p24-amplified tumors, which contained focal amplification of the Janus kinase 2 (JAK2) gene. These patients had markedly inferior recurrence-free and overall survival compared to patients with TNBC without JAK2 amplification. Detection of JAK2/9p24 amplifications was more common in chemotherapy-treated TNBCs than in untreated TNBCs or basal-like cancers, or in other breast cancer subtypes. Similar rates of JAK2 amplification were confirmed in patient-derived TNBC xenografts. In patients for whom longitudinal specimens were available, JAK2 amplification was selected for during neoadjuvant chemotherapy and eventual metastatic spread, suggesting a role in tumorigenicity and chemoresistance, phenotypes often attributed to a cancer stem cell-like cell population. In TNBC cell lines with JAK2 copy gains or amplification, specific inhibition of JAK2 signaling reduced mammosphere formation and cooperated with chemotherapy in reducing tumor growth in vivo. In these cells, inhibition of JAK1-signal transducer and activator of transcription 3 (STAT3) signaling had little effect or, in some cases, counteracted JAK2-specific inhibition. Collectively, these results suggest that JAK2-specific inhibitors are more efficacious than dual JAK1/2 inhibitors against JAK2-amplified TNBCs. Furthermore, JAK2 amplification is a potential biomarker for JAK2 dependence, which, in turn, can be used to select patients for clinical trials with JAK2 inhibitors., (Copyright © 2016, American Association for the Advancement of Science.)
- Published
- 2016
- Full Text
- View/download PDF
37. Sequential molecularly imprinted solid-phase extraction methods for the analysis of resveratrol and other polyphenols.
- Author
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Schwarz LJ, Danylec B, Harris SJ, Boysen RI, and Hearn MT
- Subjects
- Arachis chemistry, Chromatography, High Pressure Liquid, Industrial Waste analysis, Molecular Imprinting, Resveratrol, Spectrometry, Mass, Electrospray Ionization, Water chemistry, Chemistry Techniques, Analytical methods, Polyphenols analysis, Polyphenols isolation & purification, Solid Phase Extraction, Stilbenes analysis, Stilbenes isolation & purification
- Abstract
Molecularly imprinted polymers (MIPs) templated with either the phytoalexin, (E)-resveratrol, or its structural analog, 3,5-dihydroxy-N-(4-hydroxyphenyl)benzamide, have been used in tandem for the sequential extraction of (E)-resveratrol from aqueous peanut meal extracts in high purity and in near quantitative yields. Re-processing of the (E)-resveratrol-depleted peanut meal extract with the 3,5-dihydroxy-N-(4-hydroxyphenyl)benzamide imprinted MIP yielded additional polyphenolic components, identified as A-type procyanidins. Tandem liquid chromatography-electrospray ionization mass spectrometry confirmed the identity and purity of the isolated products. This study documents the advantages of tandem approaches with MIPs for the solid phase extraction and analysis of multiple bioactive compounds present in complex biomass waste streams., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
38. The Application of Template Selectophores for the Preparation of Molecularly Imprinted Polymers.
- Author
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Danylec B, Schwarz LJ, Harris SJ, Boysen RI, and Hearn MT
- Subjects
- Adsorption, Chromatography, High Pressure Liquid, Green Chemistry Technology, Molecular Mimicry, Molecular Structure, Polymers chemistry, Resveratrol, Molecular Imprinting methods, Polymers chemical synthesis, Stilbenes chemistry
- Abstract
Molecularly imprinted polymers are versatile materials with wide application scope for the detection, capture and separation of specific compounds present in complex feed stocks. A major challenge associated with their preparation has been the need to sacrifice one mole equivalent of the template molecule to generate the complementary polymer cavities that selectively bind the target molecule. Moreover, template molecules can often be difficult to synthesise, expensive or lack stability. In this study, we describe a new approach, directed at the use of synthetic selectophores, chosen as readily prepared and low cost structural analogues with recognition groups in similar three-dimensional arrangements as found in the target molecule. To validate the approach, a comparative study of selectophores related to the polyphenolic compound (E)-resveratrol has been undertaken using traditional and green chemical synthetic approaches. These molecular mimic compounds were employed as polymer templates and also as binding analytes to interrogate the recognition sites associated with the molecularly imprinted polymers. Importantly, the study confirms that the use of selectophores has the potential to confer practical advantages, including access to more efficient methods for selection and preparation of suitable template molecules with a broader range of molecular diversity, as well as delivering imprinted polymers capable of recognizing the target compound and structurally related products.
- Published
- 2015
- Full Text
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39. LYN-activating mutations mediate antiestrogen resistance in estrogen receptor-positive breast cancer.
- Author
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Schwarz LJ, Fox EM, Balko JM, Garrett JT, Kuba MG, Estrada MV, González-Angulo AM, Mills GB, Red-Brewer M, Mayer IA, Abramson V, Rizzo M, Kelley MC, Meszoely IM, and Arteaga CL
- Subjects
- Amino Acid Substitution, Aminopyridines agonists, Aminopyridines pharmacology, Animals, Breast Neoplasms drug therapy, Breast Neoplasms genetics, Breast Neoplasms pathology, Dasatinib, Drug Resistance, Neoplasm drug effects, Drug Synergism, Female, Gene Expression Regulation, Enzymologic drug effects, Gene Expression Regulation, Enzymologic genetics, Gene Expression Regulation, Neoplastic drug effects, Gene Expression Regulation, Neoplastic genetics, Humans, Mice, Mice, Nude, Morpholines agonists, Morpholines pharmacology, Phosphatidylinositol 3-Kinases genetics, Phosphatidylinositol 3-Kinases metabolism, Phosphoinositide-3 Kinase Inhibitors, Phosphorylation drug effects, Phosphorylation genetics, Protein Kinase Inhibitors pharmacology, Pyrimidines agonists, Pyrimidines pharmacology, Receptors, Estrogen genetics, Thiazoles agonists, Thiazoles pharmacology, Xenograft Model Antitumor Assays, src Homology Domains, src-Family Kinases genetics, Breast Neoplasms metabolism, Drug Resistance, Neoplasm genetics, Estrogen Receptor Modulators pharmacology, Mutation, Missense, Receptors, Estrogen metabolism, src-Family Kinases metabolism
- Abstract
Estrogen receptor-positive (ER(+)) breast cancers adapt to hormone deprivation and become resistant to antiestrogen therapy. Here, we performed deep sequencing on ER(+) tumors that remained highly proliferative after treatment with the aromatase inhibitor letrozole and identified a D189Y mutation in the inhibitory SH2 domain of the SRC family kinase (SFK) LYN. Evaluation of 463 breast tumors in The Cancer Genome Atlas revealed four LYN mutations, two of which affected the SH2 domain. In addition, LYN was upregulated in multiple ER(+) breast cancer lines resistant to long-term estrogen deprivation (LTED). An RNAi-based kinome screen revealed that LYN is required for growth of ER(+) LTED breast cancer cells. Kinase assays and immunoblot analyses of SRC substrates in transfected cells indicated that LYN(D189Y) has higher catalytic activity than WT protein. Further, LYN(D189Y) exhibited reduced phosphorylation at the inhibitory Y507 site compared with LYN(WT). Other SH2 domain LYN mutants, E159K and K209N, also exhibited higher catalytic activity and reduced inhibitory site phosphorylation. LYN(D189Y) overexpression abrogated growth inhibition by fulvestrant and/or the PI3K inhibitor BKM120 in 3 ER(+) breast cancer cell lines. The SFK inhibitor dasatinib enhanced the antitumor effect of BKM120 and fulvestrant against estrogen-deprived ER(+) xenografts but not LYN(D189Y)-expressing xenografts. These results suggest that LYN mutations mediate escape from antiestrogens in a subset of ER(+) breast cancers.
- Published
- 2014
- Full Text
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40. A comparison of covalent and non-covalent imprinting strategies for the synthesis of stigmasterol imprinted polymers.
- Author
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Hashim SN, Boysen RI, Schwarz LJ, Danylec B, and Hearn MT
- Subjects
- Solid Phase Extraction methods, Stigmasterol isolation & purification, Water Pollutants, Chemical chemistry, Water Pollutants, Chemical isolation & purification, Molecular Imprinting methods, Polymers chemical synthesis, Solid Phase Extraction instrumentation, Stigmasterol chemistry
- Abstract
Non-covalent and covalent imprinting strategies have been investigated for the synthesis of stigmasterol imprinted polymers. The synthesized molecularly imprinted polymers (MIPs) were then evaluated for their recognition and selectivity towards stigmasterol via static and dynamic batch-binding assays and their performance measured against control non-imprinted polymers (NIPs). MIPs prepared using the conventional non-covalent imprinting method displayed little to no binding affinity for stigmasterol under various conditions. In contrast, the application of a covalent imprinting approach using the novel post-synthetically cleavable monomer-template composite stigmasteryl-3-O-methacrylate resulted in the fabrication of a MIP that successfully recognized stigmasterol in both organic and partially aqueous environments. The affinity and selectivity of the covalently prepared MIP was enhanced when undertaken in a partially aqueous environment consisting of an acetonitrile/water (9:1, v/v) solvent mixture. These features have been exploited in a molecularly imprinted solid-phase extraction (MISPE) format, wherein the preferential retention of stigmasterol (with an imprint factor of 12) was demonstrated with 99% recovery in comparison to cholesterol (imprint factor of 6) and ergosterol (imprint factor of 4) while in the presence of several closely related steryl analogues., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
41. Molecular profiling of the residual disease of triple-negative breast cancers after neoadjuvant chemotherapy identifies actionable therapeutic targets.
- Author
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Balko JM, Giltnane JM, Wang K, Schwarz LJ, Young CD, Cook RS, Owens P, Sanders ME, Kuba MG, Sánchez V, Kurupi R, Moore PD, Pinto JA, Doimi FD, Gómez H, Horiuchi D, Goga A, Lehmann BD, Bauer JA, Pietenpol JA, Ross JS, Palmer GA, Yelensky R, Cronin M, Miller VA, Stephens PJ, and Arteaga CL
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cell Line, Tumor, Cluster Analysis, DNA Copy Number Variations, Drug Resistance, Neoplasm genetics, Female, Gene Amplification, Genes, myc, Humans, Ki-67 Antigen genetics, Ki-67 Antigen metabolism, Myeloid Cell Leukemia Sequence 1 Protein genetics, Neoadjuvant Therapy, Neoplasm, Residual, Prognosis, Treatment Outcome, Triple Negative Breast Neoplasms drug therapy, Triple Negative Breast Neoplasms mortality, Gene Expression Profiling, Triple Negative Breast Neoplasms genetics, Triple Negative Breast Neoplasms pathology
- Abstract
Unlabelled: Neoadjuvant chemotherapy (NAC) induces a pathologic complete response (pCR) in approximately 30% of patients with triple-negative breast cancers (TNBC). In patients lacking a pCR, NAC selects a subpopulation of chemotherapy-resistant tumor cells. To understand the molecular underpinnings driving treatment-resistant TNBCs, we performed comprehensive molecular analyses on the residual disease of 74 clinically defined TNBCs after NAC, including next-generation sequencing (NGS) on 20 matched pretreatment biopsies. Combined NGS and digital RNA expression analysis identified diverse molecular lesions and pathway activation in drug-resistant tumor cells. Ninety percent of the tumors contained a genetic alteration potentially treatable with a currently available targeted therapy. Thus, profiling residual TNBCs after NAC identifies targetable molecular lesions in the chemotherapy-resistant component of the tumor, which may mirror micrometastases destined to recur clinically. These data can guide biomarker-driven adjuvant studies targeting these micrometastases to improve the outcome of patients with TNBC who do not respond completely to NAC., Significance: This study demonstrates the spectrum of genomic alterations present in residual TNBC after NAC. Because TNBCs that do not achieve a CR after NAC are likely to recur as metastatic disease at variable times after surgery, these alterations may guide the selection of targeted therapies immediately after mastectomy before these metastases become evident., (2013 AACR)
- Published
- 2014
- Full Text
- View/download PDF
42. Rapid solid-phase extraction and analysis of resveratrol and other polyphenols in red wine.
- Author
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Hashim SN, Schwarz LJ, Boysen RI, Yang Y, Danylec B, and Hearn MT
- Subjects
- Chromatography, High Pressure Liquid, Limit of Detection, Molecular Imprinting, Polyphenols analysis, Polyphenols isolation & purification, Resveratrol, Spectrometry, Mass, Electrospray Ionization, Stilbenes analysis, Stilbenes isolation & purification, Tandem Mass Spectrometry, Polyphenols chemistry, Solid Phase Extraction methods, Stilbenes chemistry, Wine analysis
- Abstract
Red wine has long been credited as a good source of health-beneficial antioxidants, including the bioactive polyphenols catechin, quercetin, and (E)-resveratrol. In this paper, we report the application of reusable molecularly imprinted polymers (MIPs) for the selective and robust solid-phase extraction (SPE) and rapid analysis of (E)-resveratrol (LOD=8.87×10(-3) mg/L, LOQ=2.94×10(-2) mg/L), along with a range of other polyphenols from an Australian Pinot noir red wine. Optimization of the molecularly imprinted solid-phase extraction (MISPE) protocol resulted in the significant enrichment of (E)-resveratrol and several structurally related polyphenols. These secondary metabolites were subsequently identified by RP-HPLC and μLC-ESI ion trap MS/MS methods. The developed MISPE protocol employed low volumes of environmentally benign solvents selected according to the Green Chemistry principles, and resulted in the recovery of 99% of the total (E)-resveratrol present. These results further demonstrate the potential of generic protocols for the analysis of target compound with health beneficial properties within the food and nutraceutical industries using tailor-made MIPs., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
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43. Activation of MAPK pathways due to DUSP4 loss promotes cancer stem cell-like phenotypes in basal-like breast cancer.
- Author
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Balko JM, Schwarz LJ, Bhola NE, Kurupi R, Owens P, Miller TW, Gómez H, Cook RS, and Arteaga CL
- Subjects
- Animals, Breast Neoplasms genetics, Breast Neoplasms metabolism, Cell Culture Techniques, Dual-Specificity Phosphatases genetics, Dual-Specificity Phosphatases metabolism, Female, Heterografts, Humans, Mice, Mice, Nude, Mitogen-Activated Protein Kinase Phosphatases genetics, Mitogen-Activated Protein Kinase Phosphatases metabolism, Mitogen-Activated Protein Kinases metabolism, Neoplastic Stem Cells metabolism, Neoplastic Stem Cells pathology, Phenotype, Transfection, Breast Neoplasms enzymology, Breast Neoplasms pathology, Dual-Specificity Phosphatases deficiency, MAP Kinase Signaling System physiology, Mitogen-Activated Protein Kinase Phosphatases deficiency, Mitogen-Activated Protein Kinases genetics
- Abstract
Basal-like breast cancer (BLBC) is an aggressive disease that lacks a clinically approved targeted therapy. Traditional chemotherapy is effective in BLBC, but it spares the cancer stem cell (CSC)-like population, which is likely to contribute to cancer recurrence after the initial treatment. Dual specificity phosphatase-4 (DUSP4) is a negative regulator of the mitogen-activated protein kinase (MAPK) pathway that is deficient in highly aggressive BLBCs treated with chemotherapy, leading to aberrant MAPK activation and resistance to taxane-induced apoptosis. Herein, we investigated how DUSP4 regulates the MAP-ERK kinase (MEK) and c-jun-NH2-kinase (JNK) pathways in modifying CSC-like behavior. DUSP4 loss increased mammosphere formation and the expression of the CSC-promoting cytokines interleukin (IL)-6 and IL-8. These effects were caused in part by loss of control of the MEK and JNK pathways and involved downstream activation of the ETS-1 and c-JUN transcription factors. Enforced expression of DUSP4 reduced the CD44(+)/CD24(-) population in multiple BLBC cell lines in a MEK-dependent manner, limiting tumor formation of claudin-low SUM159PT cells in mice. Our findings support the evaluation of MEK and JNK pathway inhibitors as therapeutic agents in BLBC to eliminate the CSC population., (©2013 AACR.)
- Published
- 2013
- Full Text
- View/download PDF
44. Enrichment of (E)-resveratrol from peanut byproduct with molecularly imprinted polymers.
- Author
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Schwarz LJ, Danylec B, Yang Y, Harris SJ, Boysen RI, and Hearn MT
- Subjects
- Chromatography, High Pressure Liquid, Magnetic Resonance Spectroscopy, Resveratrol, Solid Phase Microextraction, Spectrometry, Mass, Electrospray Ionization, Tandem Mass Spectrometry, Arachis chemistry, Polymers chemistry, Stilbenes analysis
- Abstract
Molecularly imprinted solid phase extraction (MISPE) has been employed to isolate and concentrate bioactive polyphenols from peanut press waste. To this end, a molecularly imprinted polymer (MIP) templated with the phytoalexin (E)-resveratrol has been prepared via self-assembly with the functional monomer 4-vinylpyridine (4VP) in a 1:3 molar ratio. Subsequent molecular interrogation of the MIP binding sites demonstrated preferential structural selectivity for (E)-resveratrol with respect to other structurally related naturally occurring compounds. This selectivity was subsequently exploited to achieve substantial sample cleanup of peanut press waste under aqueous conditions with significant enrichment of (E)-resveratrol (>60 fold) requiring minimal sample preparation.
- Published
- 2011
- Full Text
- View/download PDF
45. Preparation of molecularly imprinted polymers for the selective recognition of the bioactive polyphenol, (E)-resveratrol.
- Author
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Schwarz LJ, Danylec B, Harris SJ, Boysen RI, and Hearn MT
- Subjects
- Chromatography, High Pressure Liquid, Models, Molecular, Phenols chemistry, Pyridines, Resveratrol, Solid Phase Extraction, Molecular Imprinting, Polymers chemistry, Stilbenes chemistry
- Abstract
(E)-Resveratrol imprinted polymers have been rationally designed with the aid of molecular modelling and NMR spectroscopic titration techniques to determine the optimal ratio of the template to functional monomer for polymer formation. Based on this approach, (E)-resveratrol imprinted polymers were prepared via non-covalent self-assembly with the functional monomer 4-vinylpyridine (4VP) in a 1:3 molar ratio. Polymerisation in the presence of a cross-linker resulted in rigid block copolymers that had selective capacities towards (E)-resveratrol (e.g. 14 μmol/g) when compared to the non-imprinted reference polymer. The selectivity of these MIPs was also examined using several structurally related polyphenolic compounds to determine the influence of polyphenolic hydroxyl number and position on binding and molecular recognition., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
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