Search

Alzheimer's disease and related dementias (ADRD) often result in communication deficits that can lead to negative health outcomes as well as complications for caregiving and clinical care. Although augmentative and alternative communication (AAC) devices have demonstrated efficacy in assisting persons living with dementia (PLWD) in communicating, few devices offer customization for the person's care preferences (e.g., clothing, food, activities) or are designed for integration into clinical care and caregiving. To address this issue, our research team is developing a novel electronic AAC prototype with a touchscreen to promote communication and personhood for PLWD. The current article describes the development of this technology and uses the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2013 Statement to describe the clinical trial that is planned to test its efficacy. TARGETS: PLWD and their care partners. INTERVENTION DESCRIPTION: Use of AAC Plus to promote communication and personhood for PLWD. MECHANISMS OF ACTION: AAC Plus will provide PLWD and care partners a way to communicate PLWD's daily preferences and provide clinical data for health care providers. OUTCOMES: Determine whether enhanced communication of daily preferences of PLWD will improve quality of life of PLWD and their care partners. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04571502 (Date of registration October 1, 2020). [ Research in Gerontological Nursing, 14 (5), 225–234.]

More than two decades ago, a recessive syndromic phenotype affecting kidneys, eyes, and ears, was first described in the endogamous Afrikaner population of South Africa. Using whole-exome sequencing of DNA from two affected siblings (and their carrier parents), we identified the novel RRM2B c.786G>T variant as a plausible disease-causing mutation. The RRM2B gene is involved in mitochondrial integrity, and the observed change was not previously reported in any genomic database. The subsequent screening revealed the variant in two newly presenting unrelated patients, as well as two patients in our registry with rod-cone dystrophy, hearing loss, and Fanconi-type renal disease. All patients with the c.786G>T variant share an identical 1.5 Mb haplotype around this gene, suggesting a founder effect in the Afrikaner population. We present ultrastructural evidence of mitochondrial impairment in one patient, to support our thesis that this RRM2B variant is associated with the renal, ophthalmological, and auditory phenotype.

© 2020 The Authors. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/), The cause of autosomal-dominant retinitis pigmentosa (adRP), which leads to loss of vision and blindness, was investigated in families lacking a molecular diagnosis. A refined locus for adRP on Chr17q22 (RP17) was delineated through genotyping and genome sequencing, leading to the identification of structural variants (SVs) that segregate with disease. Eight different complex SVs were characterized in 22 adRP-affected families with >300 affected individuals. All RP17 SVs had breakpoints within a genomic region spanning YPEL2 to LINC01476. To investigate the mechanism of disease, we reprogrammed fibroblasts from affected individuals and controls into induced pluripotent stem cells (iPSCs) and differentiated them into photoreceptor precursor cells (PPCs) or retinal organoids (ROs). Hi-C was performed on ROs, and differential expression of regional genes and a retinal enhancer RNA at this locus was assessed by qPCR. The epigenetic landscape of the region, and Hi-C RO data, showed that YPEL2 sits within its own topologically associating domain (TAD), rich in enhancers with binding sites for retinal transcription factors. The Hi-C map of RP17 ROs revealed creation of a neo-TAD with ectopic contacts between GDPD1 and retinal enhancers, and modeling of all RP17 SVs was consistent with neo-TADs leading to ectopic retinal-specific enhancer-GDPD1 accessibility. qPCR confirmed increased expression of GDPD1 and increased expression of the retinal enhancer that enters the neo-TAD. Altered TAD structure resulting in increased retinal expression of GDPD1 is the likely convergent mechanism of disease, consistent with a dominant gain of function. Our study highlights the importance of SVs as a genomic mechanism in unsolved Mendelian diseases.

Background Over the past decade, there has been an increase in the use of information technologies to educate and support people with dementia and their family caregivers. At the same time, chatbot technologies have become increasingly popular for use by the public and have been identified as having benefits for health care delivery. However, little is known about how chatbot technologies may benefit people with dementia and their caregivers. Objective This study aims to identify the types of current commercially available chatbots that are designed for use by people with dementia and their caregivers and to assess their quality in terms of features and content. Methods Chatbots were identified through a systematic search on Google Play Store, Apple App Store, Alexa Skills, and the internet. An evidence-based assessment tool was used to evaluate the features and content of the identified apps. The assessment was conducted through interrater agreement among 4 separate reviewers. Results Of the 505 initial chatbots identified, 6 were included in the review. The chatbots assessed varied significantly in terms of content and scope. Although the chatbots were generally found to be easy to use, some limitations were noted regarding their performance and programmed content for dialog. Conclusions Although chatbot technologies are well established and commonly used by the public, their development for people with dementia and their caregivers is in its infancy. Given the successful use of chatbots in other health care settings and for other applications, there are opportunities to integrate this technology into dementia care. However, more evidence-based chatbots that have undergone end user evaluation are needed to evaluate their potential to adequately educate and support these populations.

ObjectivesAmid a political agenda for integrated, high-value care, the UK is implementing its Low Back and Radicular Pain Pathway. To align care with need, it is imperative to understand the patients’ perspective. The purpose of this study was, therefore, to explore how people experience being managed for sciatica within an National Health Service (NHS) pathway.DesignQualitative interpretative study.SettingMusculoskeletal Service in an NHS, Primary Care Trust, UK.ParticipantsThe sample comprised 14 people aged ≥18 years with a clinical presentation of sciatica, who were currently under the care of a specialist physiotherapist (the specialist spinal triage practitioner), had undergone investigations (MRI) and received the results within the past 6 weeks. People were excluded if they had previously undergone spinal surgery or if the suspected cause of symptoms was cauda equina syndrome or sinister pathology. Participants were sampled purposively for variation in age and gender. Data were collected using individual semi-structured interviews (duration: 38–117 min; median: 82.6 min), which were audio-recorded and transcribed verbatim. Data were analysed thematically.ResultsA series of problems with the local pathway (insufficient transparency and information; clinician-led decisions; standardised management; restricted access to specialist care; and a lack of collaboration between services) made it difficult for patients to access the management they perceived necessary. Patients were therefore required to be independent and proactive or have agency. This was, however, difficult to achieve (due to the impact of sciatica and because patients lacked the necessary skills, funds and support) and together with the pathway issues, this negated patients’ capability to manage sciatica.ConclusionsThis novel paper explores how patients experience the process of being managed within a sciatica pathway. While highlighting the need to align with recommended best practice, it shows the need to be more person-centred and to support and empower patient agency.Trial registration numberClinicalTrials.gov reference (UOS-2307-CR); Pre-results.

Acute interstitial nephritis is a well-known cause of acute kidney injury, but its association with cocaine use is extremely rare. In this article, we chronicle the case of a patient who developed acute interstitial nephritis secondary to cocaine insufflation. Furthermore, we conducted a systematic literature search of MEDLINE, Cochrane, Embase, and Scopus databases regarding cocaine-induced acute interstitial nephritis. A comprehensive review of the search results yielded a total of 7 case reports only. The data on patient characteristics, clinical features, biochemical profiles, treatment, and outcomes were collected and analyzed. This paper illustrates that acute interstitial nephritis may be added to the list of differentials in patients with acute kidney injury and a history of cocaine use. The therapeutic approach for cocaine-related kidney disease may be different than other etiologies responsible for acute renal insult. Prompt recognition of this entity is crucial because such patients may ultimately develop severe deterioration in renal function.

Purpose: Missing heritability in human diseases represents a major challenge, and this is particularly true for ABCA4-associated Stargardt disease (STGD1). We aimed to elucidate the genomic and transcriptomic variation in 1054 unsolved STGD and STGD-like probands. Methods: Sequencing of the complete 128-kb ABCA4 gene was performed using single-molecule molecular inversion probes (smMIPs), based on a semiautomated and cost-effective method. Structural variants (SVs) were identified using relative read coverage analyses and putative splice defects were studied using in vitro assays. Results: In 448 biallelic probands 14 known and 13 novel deep-intronic variants were found, resulting in pseudoexon (PE) insertions or exon elongations in 105 alleles. Intriguingly, intron 13 variants c.1938-621G>A and c.1938-514G>A resulted in dual PE insertions consisting of the same upstream, but different downstream PEs. The intron 44 variant c.6148-84A>T resulted in two PE insertions and flanking exon deletions. Eleven distinct large deletions were found, two of which contained small inverted segments. Uniparental isodisomy of chromosome 1 was identified in one proband. Conclusion: Deep sequencing of ABCA4 and midigene-based splice assays allowed the identification of SVs and causal deep-intronic variants in 25% of biallelic STGD1 cases, which represents a model study that can be applied to other inherited diseases. Fil: Khan, Mubeen. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Cornelis, Stéphanie S.. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Del Pozo Valero, Marta. Hospital Universitario Fundación Jiménez Díaz; España. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Whelan, Laura. Trinity College; Estados Unidos Fil: Runhart, Esmee H.. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Mishra, Ketan. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Bults, Femke. Radboud University Nijmegen Medical Centre; Países Bajos Fil: AlSwaiti, Yahya. St John of Jerusalem Eye Hospital Group; Palestina (ANP) Fil: AlTalbishi, Alaa. St John of Jerusalem Eye Hospital Group; Palestina (ANP) Fil: De Baere, Elfride. University of Ghent; Bélgica Fil: Banfi, Sandro. Seconda Universita Degli Studi Di Napoli; Italia Fil: Banin, Eyal. The Hebrew University of Jerusalem; Israel Fil: Bauwens, Miriam. University of Ghent; Bélgica Fil: Ben Yosef, Tamar. The Ruth And Bruce Rappaport Faculty Of Medicine; Israel Fil: Boon, Camiel J. F.. Leiden University. Leiden University Medical Center; Países Bajos Fil: van den Born, L. Ingeborgh. Rotterdam Ophthalmic Institute; Países Bajos Fil: Defoort, Sabine. Universite Lille; Francia Fil: Devos, Aurore. Universite Lille; Francia Fil: Dockery, Adrian. Trinity College; Estados Unidos Fil: Dudakova, Lubica. Charles University and General University Hospital; República Checa Fil: Fakin, Ana. Charles University and General University Hospital; República Checa Fil: Farrar, G. Jane. Trinity College; Estados Unidos Fil: Ferraz Sallum, Juliana Maria. Universidade Federal de Sao Paulo; Brasil Fil: Fujinami, Kaoru. UCL Institute of Ophthalmology; Reino Unido Fil: Gilissen, Christian. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Glavac, Damjan. University of Ljubljana; Eslovenia Fil: Gorin, Michael B.. University of California at Los Angeles. School of Medicine; Estados Unidos Fil: Greenberg, Jacquie. University of Cape Town; Sudáfrica Fil: Hayashi, Takaaki. The Jikei University School of Medicine; Japón Fil: Hettinga, Ymkje M.. Bartiméus Diagnostic Center for Complex Visual Disorders; Países Bajos Fil: Hoischen, Alexander. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Hoyng, Carel B.. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Hufendiek, Karsten. University Eye Hospital Hannover Medical School; Alemania Fil: Jägle, Herbert. University Regensburg; Alemania Fil: Kamakari, Smaragda. OMMA Ophthalmological Institute of Athens; Grecia Fil: Karali, Marianthi. Seconda Universita Degli Studi Di Napoli; Italia Fil: Kellner, Ulrich. No especifíca; Fil: Klaver, Caroline C. W.. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Kousal, Bohdan. Charles University and General University Hospital; República Checa Fil: Lamey, Tina M.. University of Western Australia; Australia Fil: MacDonald, Ian M.. University of Alberta; Canadá Fil: Matynia, Anna. University of California at Los Angeles. School of Medicine; Estados Unidos Fil: McLaren, Terri L.. University of Western Australia; Australia Fil: Mena, Marcela D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina Fil: Meunier, Isabelle. Université Montpellier II; Francia Fil: Miller, Rianne. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Newman, Hadas. Universitat Tel Aviv; Israel Fil: Ntozini, Buhle. University of Cape Town; Sudáfrica Fil: Oldak, Monika. No especifíca; Fil: Pieterse, Marc. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Podhajcer, Osvaldo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina Fil: Puech, Bernard. Universite Lille; Francia Fil: Ramesar, Raj. University of Cape Town; Sudáfrica Fil: Rüther, Klaus. No especifíca; Fil: Salameh, Manar. No especifíca; Fil: Salles, Mariana Vallim. Universidade de Sao Paulo; Brasil Fil: Sharon, Dror. The Hebrew University of Jerusalem; Israel Fil: Simonelli, Francesca. Seconda Universita Degli Studi Di Napoli; Italia Fil: Spital, Georg. No especifíca; Fil: Steehouwer, Marloes. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Szaflik, Jacek P.. No especifíca; Fil: Thompson, Jennifer A.. No especifíca; Fil: Thuillier, Caroline. Universite Lille; Francia Fil: Tracewska, Anna M.. No especifíca; Fil: van Zweeden, Martine. Radboud University Nijmegen Medical Centre; Países Bajos Fil: Vincent, Andrea L.. University of Auckland; Nueva Zelanda Fil: Zanlonghi, Xavier. No especifíca; Fil: Liskova, Petra. Charles University and General University Hospital; República Checa Fil: Stöhr, Heidi. Universitat Regensburg; Alemania Fil: De Roach, John N.. University of Western Australia; Australia Fil: Ayuso, Carmen. Hospital Universitario Fundación Jiménez Díaz; España Fil: Roberts, Lisa. University of Cape Town; Sudáfrica Fil: Weber, Bernhard H. F.. Universitat Regensburg; Alemania Fil: Dhaenens, Claire Marie. Universite Lille; Francia Fil: Cremers, Frans P. M.. Radboud University Nijmegen Medical Centre; Países Bajos

Missing heritability in human diseases represents a major challenge. Although whole-genome sequencing enables the analysis of coding and non-coding sequences, substantial costs and data storage requirements hamper its large-scale use to (re)sequence genes in genetically unsolved cases. The ABCA4 gene implicated in Stargardt disease (STGD1) has been studied extensively for 22 years, but thousands of cases remained unsolved. Therefore, single molecule molecular inversion probes were designed that enabled an automated and cost-effective sequence analysis of the complete 128-kb ABCA4 gene. Analysis of 1,054 unsolved STGD and STGD-like probands resulted in bi-allelic variations in 448 probands. Twenty-seven different causal deep-intronic variants were identified in 117 alleles. Based on in vitro splice assays, the 13 novel causal deep-intronic variants were found to result in pseudo-exon (PE) insertions (n=10) or exon elongations (n=3). Intriguingly, intron 13 variants c.1938-621G>A and c.1938-514G>A resulted in dual PE insertions consisting of the same upstream, but different downstream PEs. The intron 44 variant c.6148-84A>T resulted in two PE insertions that were accompanied by flanking exon deletions. Structural variant analysis revealed 11 distinct deletions, two of which contained small inverted segments. Uniparental isodisomy of chromosome 1 was identified in one proband. Integrated complete gene sequencing combined with transcript analysis, identified pathogenic deep-intronic and structural variants in 26% of bi-allelic cases not solved previously by sequencing of coding regions. This strategy serves as a model study that can be applied to other inherited diseases in which only one or a few genes are involved in the majority of cases.

Background Epidermal growth factor receptor (EGFR) alterations are associated with multiple cancers. Current EGFR-directed therapies have led to increased efficacy but are associated with specific side effects. The antibody-drug conjugate depatuxizumab mafodotin (depatux-m) targets EGFR with a monoclonal antibody linked to a cytotoxin, and is highly tumor-specific. Methods This phase 1/2 study evaluated the safety, pharmacokinetics, and efficacy of depatux-m in patients who had advanced solid tumors with known wild-type EGFR overexpression, amplification, or mutated EGFR variant III. A 3 + 3 dose escalation was used, and 2 dosing schedules were evaluated. Depatux-m also was manufactured under an alternate process to reduce the drug load and improve the safety profile, and it was tested at the maximum tolerated dose (MTD). In another cohort, prolonged infusion time of depatux-m was evaluated; and a cohort with confirmed EGFR amplification also was evaluated at the MTD. Results Fifty-six patients were treated. The MTD and the recommended phase 2 dose for depatux-m was 3.0 mg/kg. Common adverse events (AEs) were blurred vision (48%) and fatigue (41%). A majority of patients (66%) experienced 1 or more ocular AEs. Grade 3 or 4 AEs were observed in 43% of patients. One patient with EGFR-amplified, triple-negative breast cancer had a partial response. Stable disease was observed in 23% of patients. Pharmacokinetics revealed that depatux-m exposures were approximately dose-proportional. Conclusions Depatux-m resulted in infrequent nonocular AEs but increased ocular AEs. Patient follow-up confirmed that ocular AEs were reversible. Lowering the drug-antibody ratio did not decrease the number of ocular AEs. A partial response in 1 patient with EGFR-amplified disease provides the opportunity to study depatux-m in diseases with a high incidence of EGFR amplification. Cancer 2018;124:2174-83. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Epidermal growth factor receptor (EGFR) amplification has been reported to occur in ~ 50% of glioblastomas (GBMs). We are conducting several global studies that require central testing for EGFR amplification during screening, representing an opportunity to confirm the frequency of amplification in GBM in a large cohort and to evaluate whether EGFR amplification differs by region of the world. EGFR amplification was measured by fluorescence in situ hybridization during screening for therapeutic trials of an EGFR antibody–drug conjugate: two Phase 2/3 global trials (INTELLANCE-1, INTELLANCE-2), and a Japanese Phase 1/2 trial (INTELLANCE-J). We evaluated the proportion of tumor tissue samples harboring EGFR amplification among those tested and differences in amplification frequency by geography. EGFR was amplified in 54% of 3150 informative cases screened for INTELLANCE-1 and -2, consistent with historic controls, but was significantly lower in patients from Asia versus the rest of the world (35% vs. 56%, P

RPGR exon ORF15 variants are one of the most frequent causes for inherited retinal disorders (IRDs), in particular retinitis pigmentosa. The low sequence complexity of this mutation hotspot makes it prone to indels and challenging for sequence data analysis. Whole-exome sequencing generally fails to provide adequate coverage in this region. Therefore, complementary methods are needed to avoid false positives as well as negative results. In this study, next-generation sequencing (NGS) was used to sequence long-range PCR amplicons for an IRD cohort of African ancestry. By developing a novel secondary analysis pipeline based on de novo assembly, we were able to avoid the miscalling of variants generated by standard NGS analysis tools. We identified pathogenic variants in 11 patients (13% of the cohort), two of which have not been reported previously. We provide a novel and alternative end-to-end secondary analysis pipeline for targeted NGS of ORF15 that is less prone to false positive and negative variant calls., Genes, 11 (7)

BACKGROUND: Depatuxizumab mafodotin (depatux-m, formerly ABT-414) is an EGFR-directed antibody-drug conjugate being developed for treatment of EGFR-amplified glioblastoma (GBM). As therapeutic pressure engenders tumor adaptations, it is important to understand the stability of biomarkers targeted by precision medicine approaches such as depatux-m. Therefore, we assessed EGFR amplification (amp) and expression in longitudinally-sampled GBMs from patients (pts) treated +/- depatux-m to explore biomarker stability. MATERIAL AND METHODS: Formalin-fixed, paraffin embedded GBM tumor tissue was analyzed from 68 patients who underwent at least 2 surgeries; EGFR amp was detected by in situ hybridization (e.g., FISH) or next-generation sequencing in all samples. Fifty-six pts did not receive depatux-m; among 12 pts who did, EGFR expression was also evaluated by RNA sequencing. RESULTS: Of 56 pts who did not receive depatux-m, 31 (55%) had tumors harboring EGFR amp at 1st surgery (initial diagnosis); among those, EGFR amp was maintained at re-operation in 27 (87%), and not maintained in 4 (13%). None of the 25 cases without baseline EGFR amp acquired it at the 2nd surgery. Of 12 pts treated with depatux-m between surgeries, 9 cases harbored EGFR amp at baseline which was maintained in 4 (44%) at the 2(nd) surgery, all 4 of which had the highest levels of EGFR expression at baseline. Of the 3 cases without EGFR amp at baseline, none acquired amplification at the 2(nd) surgery, and all 3 had the lowest levels of EGFR expression at study start. CONCLUSION: The presence of EGFR amp in GBM tissue at baseline was maintained at 2(nd) surgery in 87% of pts who received treatment other than depatux-m, and in 44% following depatux-m exposure. Therefore, depatux-m exposure appears to reduce EGFR amp maintenance (p=0.0159 by Fisher’s exact test); accordingly, the therapeutic approach may influence EGFR status. In no case was EGFR amp acquired at recurrence, regardless of depatux-m therapy. Ongoing analyses of additional tumor samples will increase power and further examine concordance among EGFR amp assays.

The purpose of the current feasibility study was to examine the use, utility, and areas for refinement of a newly developed web-based and Android ™ application (app) (i.e., CareHeroes) with multiple features to support individuals caring for loved ones with Alzheimer's disease or other forms of dementia (AD). The study was performed over an 11-week period with triads of AD caregivers, assigned home care case managers, and primary care providers (PCP). The study involved quantitative and qualitative methodologies. Eleven AD caregivers (seven daughters, two sons, and two spouses), six case managers, and five PCPs participated. Data demonstrate participants were mostly satisfied with the multiple features and ability to access and use CareHeroes. Barriers for use include concerns about time constraints and not being familiar with technology. Although the study findings are promising, a longer term study to evaluate the impact of the CareHeroes app is indicated. [Res Gerontol Nurs. 2016; 9(4): 193–203.]

To evaluate the rates and characteristics of musculoskeletal disorders (MSDs) in physical therapists (PTs) according to their specialty and setting.Participants completed an online questionnaire including 15 demographic questions, 7 work-related and 8 injury-related questions for 9 different body parts.Complete responses were obtained from 121 PTs; 96% reported MSD symptoms during the previous 12 months, 64% affecting at least 3 body parts. The body parts with the highest prevalence of symptoms were the low back (66%) and the neck (61%). For PTs specialized in acute care, geriatrics and pediatrics, the body part most commonly affected was the low back, while for PTs specialized in orthopedics and neurology, the body part most commonly affected was the neck. Regarding work settings, the low back was the most commonly affected for PTs working in skilled nursing facilities, outpatient clinics and hospitals, and the neck in PTs working in academic and home health settings.MSDs are common among PTs; the body parts most often affected were the low back and neck. The prevalence and body parts affected varied by practice setting and specialty area. The findings can help informing the design of evidence-based rehabilitation, prevention, training and educational programs.Rehabilitation of injured physical therapists needs to address the symptoms of the multiple body parts that are usually affected (e.g. back, wrists and hands). Rehabilitation of injured physical therapists needs to take into consideration their job demands, practice setting and specialty area. The findings can inform the design of rehabilitation, prevention, training and educational programs for physical therapists.

Objective: To determine the feasibility of a Dance Centre delivering a programme of mixed dances to people with Parkinson’s and identify suitable outcomes for a future definitive trial. Design: A two-group randomized controlled feasibility trial. Methods: People with Parkinson’s were randomized to a control or experimental group (ratio 15:35), alongside usual care. In addition, participants in the experimental group danced with a partner for one hour, twice-a-week for 10 weeks; professional dance teachers led the classes and field-notes were kept. Control-group participants were given dance class vouchers at the end of the study. Blinded assessments of balance, mobility and function were completed in the home. Qualitative interviews were conducted with a subsample to explore the acceptability of dance. Results: A total of 51 people with Parkinson’s (25 male) with Hoehn and Yahr scores of 1–3 and mean age of 71 years (range 49–85 years), were recruited to the study. Dance partners were of similar age (mean 68, range 56–91 years). Feasibility findings focused on recruitment (target achieved); retention (five people dropped out of dancing); outcome measures (three measures were considered feasible, changes were recommended). Proposed sample size for a Phase III trial, based on the 6-minute walk test at six months was 220. Participants described dance as extremely enjoyable and the instructors were skilled in instilling confidence and motivation. The main organizational challenges for a future trial were transport and identifying suitable dance partners. Conclusion: We have demonstrated the feasibility of conducting the study through a Dance Centre and recommend a Phase III trial.

Background Venetoclax (ABT-199), a first-in-class orally bioavailable BCL-2-selective inhibitor, was recently approved by the FDA for use in patients with 17p-deleted chronic lymphocytic leukemia who have received prior therapy. It is also being evaluated in numerous clinical trials for treating patients with various hematologic malignancies. As with any targeted cancer therapy, it is critically important to identify potential mechanisms of resistance, both for patient stratification and developing strategies to overcome resistance, either before it develops or as it emerges. Methods In order to gain a more comprehensive insight into the nature of venetoclax resistance mechanisms, we evaluated the changes in the BCL-2 family members at the genetic and expression levels in seven different venetoclax-resistant derived leukemia and lymphoma cell lines. Results Gene and protein expression analyses identified a number of different alterations in the expression of pro- and anti-apoptotic BCL-2 family members. In the resistant derived cells, an increase in either or both the anti-apoptotic proteins BCL-XL or MCL-1, which are not targeted by venetoclax was observed, and either concomitant or exclusive with a decrease in one or more pro-apoptotic proteins. In addition, mutational analysis also revealed a mutation in the BH3 binding groove (F104L) that could potentially interfere with venetoclax-binding. Not all changes may be causally related to venetoclax resistance and may only be an epiphenomenon. For resistant cell lines showing elevations in BCL-XL or MCL-1, strong synergistic cell killing was observed when venetoclax was combined with either BCL-XL- or MCL-1-selective inhibitors, respectively. This highlights the importance of BCL-XL- and MCL-1 as causally contributing to venetoclax resistance. Conclusions Overall our study identified numerous changes in multiple resistant lines; the changes were neither mutually exclusive nor universal across the cell lines tested, thus exemplifying the complexity and heterogeneity of potential resistance mechanisms. Identifying and evaluating their contribution has important implications for both patient selection and the rational development of strategies to overcome resistance. Electronic supplementary material The online version of this article (doi:10.1186/s12885-017-3383-5) contains supplementary material, which is available to authorized users.

Item does not contain fulltext PURPOSE: To identify the genetic cause of and describe the phenotype in 4 families with autosomal recessive retinitis pigmentosa (arRP) that can be associated with pseudocoloboma. DESIGN: Case series. PARTICIPANTS: Seven patients from 4 unrelated families with arRP, among whom 3 patients had bilateral early-onset macular pseudocoloboma. METHODS: We performed homozygosity mapping and whole-exome sequencing in 5 probands and 2 unaffected family members from 4 unrelated families. Subsequently, Sanger sequencing and segregation analysis were performed in additional family members. We reviewed the medical history of individuals carrying IDH3A variants and performed additional ophthalmic examinations, including full-field electroretinography, fundus photography, fundus autofluorescence imaging, and optical coherence tomography. MAIN OUTCOME MEASURES: IDH3A variants, age at diagnosis, visual acuity, fundus appearance, visual field, and full-field electroretinography, fundus autofluorescence, and optical coherence tomography findings. RESULTS: We identified 7 different variants in IDH3A in 4 unrelated families, that is, 5 missense, 1 nonsense, and 1 frameshift variant. All participants showed symptoms early in life, ranging from night blindness to decreased visual acuity, and were diagnosed between the ages of 1 and 11 years. Four participants with biallelic IDH3A variants displayed a typical arRP phenotype and 3 participants were diagnosed with arRP and pseudocoloboma of the macula. CONCLUSIONS: IDH3A variants were identified as a novel cause of typical arRP in some individuals associated with macular pseudocoloboma. We observed both phenotypes in 2 siblings carrying the same compound heterozygous variants, which could be explained by variable disease expression and warrants caution when making assertions about genotype-phenotype correlations.

Background: Depatux-M (ABT-414) is an antibody-drug-conjugate consisting of an antibody (ABT-806) bound to the toxin monomethylauristatin-F. A randomized phase II trial on EGFR-amplified recurrent glioblastomas (GBMs) showed an improvement (p=0.06 in the primary analysis, p=0.024 in follow-up analysis) in overall survival in the Depatux-M+TMZ arm when compared to the control arm (CCNU or TMZ). In this study, we performed targeted next generation sequencing and correlated molecular features with response to treatment in order to better identify patients that benefit from the combination. Material and Methods: DNA and RNA was isolated from samples, collected at initial diagnosis, and selected for regions with highest tumor content. Target selection was done using the Trusight 170 gene panel (Illumina) which interrogates somatic variants and copy number, RNA levels and fusion genes in a set of known cancer genes. Variant calling was done using the Illumina Basespace sequence hub. For this trial, patients were eligible with centrally confirmed EGFR amplification, defined as EGFR/CEP 7 (centromere) ratio ≥ 2 in 15% of cells (FISH). Results: DNA and RNA data were generated from 233 and 234 samples respectively (of the 260 study patients). High-copy gene amplification was detected in EGFR (n=202), MDM2 (n=20), MDM4 (n=22), CDK4 (n=24) and CDK6 (n=5) which correlated with high expression levels. With this assay, 17 tumors did not show EGFR copy number (cn) aberrations (cn < 2.8), a further 14 showed copy number changes consistent with trisomy only (2.8< cn < 4). Most EGFR amplified tumors also had additional genetic changes in the EGFR locus including point mutations (111/202), splice variants (132/202, the most common being EGFRvIII n=96) or fusion genes (13/202). Twenty-one samples did not contain additional genetic changes and expressed only EGFRwt. Response (OS) to treatment was not correlated to EGFR gene expression or amplification levels though, since EGFR amplification was a pre-requisite for inclusion, the majority of cases expressed high levels of EGFR (not shown). Preliminary analysis suggests that subjects with EGFR amplification but without EGFRvIII expression had a trend towards superior clinical benefit from Depatux-M +TMZ (median survival 14.3 v. 8.9 and 8.1 months in the Depatux-M +TMZ, TMZ|CCNU and Depatux M arms respectively; HR 0.56, P=0.047 v. Depatux M monotherapy and HR 0.54, P=0.055 v. TMZ|CCNU ). Conclusion: Depatux-M in combination with TMZ showed a trend towards improved OS in EGFR amplified recurrent glioblastoma. This trend may be greater for subjects with an absence of EGFRvIII expression. Citation Format: Pim J. French, Johan M. Kros, Iris de Heer, Marica Eoli, Juan Manuel Sepulvada, Annemiek Walenkamp, Jean-Sebastian Frenel, Alba Brandes, Paul Clement, Michael Weller, Peter Ansell, Jim Looman, Earle Bain, Lisa Roberts-Rapp, Marie Morfouace, Thierry Gorlia, Vassilis Golfinopoulos, Martin van den Bent. Patients with EGFR amplification but without EGFRvIII expression have improved benefit compared to those with EGFRvIII expression in samples of the INTELLANCE2/EORTC1410 randomized phase II trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4886.

Preclinical Research The quest for a well-validated, non-invasive biomarker to aid in clinical decision making has remained elusive in the cancer space over the last 30 years. Much promise has been attached to circulating tumor cells (CTCs) as prognostic, predictive, and pharmacodynamic biomarkers with the potential to eliminate the need for invasive tumor biopsies and improve on the clinical value of other circulating tumor markers. The CellSearch® system (Veridex, LLC., Raritan, NJ, USA) cleared the U.S. Food and Drug Administration when the presence of CTCs was shown to have prognostic significance in patients with breast, prostate, and colorectal cancer. However, CTCs are not, at present, routinely being used in the clinic to guide treatment decisions. This paper discusses key attributes that a biomarker must possess, the status of other potential cancer biomarkers, and advancements in the capture and characterization of CTCs that will enable actualization of their potential as a reliable and efficient biomarker of disease diagnosis, progression, and response to therapy in the clinic.

Aim To explore the significance of circulating tumor cells (CTCs) detection in the course of preoperative chemotherapy (PC) and their effect on the outcomes. Methods Fifty-five patients with stage II/III invasive breast cancer were enrolled into a preoperative clinical trial. Patients were given PC with sequential single-agent doxorubicin and paclitaxel vs paclitaxel followed by doxorubicin. Blood samples (8 mL) were collected from patients before PC, after each phase, and at 6 months intervals during follow-up. Peripheral blood mononuclear cells were isolated and enriched for epithelial cells. Quantitative RT-PCR was used to determine the presence of cytokeratin 19 (CK19) mRNA. Samples were considered positive when the PCR curve crossed the standard threshold curve. Results After the first phase of chemotherapy, there was a 59% overall reduction in the median tumor volume. The percentage of volume reduction did not differ between patients who presented with detectable CTCs at baseline and those who did not (p=0.89). After the second phase of chemotherapy, there was a further decrease in the median tumor volume to 93% from baseline. There was no correlation between the lack of response and the presence of CTCs either after the first (p=0.36) or second (p=0.5391) phases of PC. The presence of CTCs was a predictor of local or distant relapse (p=0.0411). The detection of CTCs did not affect overall survival (p=0.2569). Conclusion CTCs can be used as predictors of relapse after definitive treatment of locally advanced breast cancer; however, CTCs detection in peripheral blood during the course of PC does not implicate a particular pattern of response to treatment.

Purpose Research over the past 25 years at the University of Cape Town has led to the identification of causative mutations in 17% of the 1416 families in the Retinal Degenerative Diseases (RDD) biorepository in South Africa. A low rate of mutation detection has been observed in patients of indigenous African origin, hinting at novel genes and mutations in this population. Recently, however, data from our translational research program showed two unrelated indigenous African families with Usher syndrome (USH), with the same homozygous MYO7A mutation. Therefore, the extent to which this mutation contributes toward the disease burden in South Africa was investigated. Methods Cohorts of unrelated indigenous South African probands with different RDD diagnoses were tested for the MYO7A c.6377delC mutation. Familial cosegregation analysis was performed for homozygous probands, clinical data were evaluated, and SNP haplotypes were analyzed. Results This homozygous MYO7A mutation underlies a remarkable 43% of indigenous African USH cases investigated in this study, the majority of which (60%) were diagnosed clinically with Type 2 USH. All homozygotes shared a common haplotype. This mutation does not appear to cause nonsyndromic vision loss. Conclusions Of interest is the origin of this common mutation relevant to the Bantu population migration into southern Africa. Further investigation of the phenotype may elucidate the disease biology, and perhaps reveal a larger cohort with the same mutation, with which to assess the impact of environmental and genetic modifiers and evaluate therapeutic trials.

2033Background: Depatuxizumab mafodotin (depatux-m, formerly ABT-414) is an EGFR-directed antibody-drug conjugate being developed for treatment of EGFR-amplified glioblastoma (GBM). As therapeutic ...

Background: Aberrant EGFR plays a vital role in the oncogenesis of multiple tumor types. ABBV-221 is a 2nd-generation antibody-drug conjugate (ADC) targeting EGFR, based on the 1st-generation ADC depatuxizumab mafodotin (depatux-m, formerly ABT-414). Depatux-m demonstrates efficacy in glioblastoma (GBM) patients (pts) with EGFR amplification in ongoing studies. ABBV-221 is an affinity matured monoclonal antibody against EGFR linked to the microtubule toxin monomethylauristatin E. ABBV-221 has higher affinity for EGFR than depatux-m, potentially allowing it to target a broader range of tumor types. To understand the population most suitable for ABBV-221, molecular assays characterizing EGFR pathway status, including EGFR protein, EGFR mRNA, and EGFR ligand mRNA expression, were evaluated from available tumor tissue of enrolled patients. The results of each assay were correlated with patient outcome to determine which marker may be best associated with prognosis. Methods: In this phase 1, multicenter study of ABBV-221, eligible pts have solid tumors that are likely to overexpress EGFR. EGFR protein expression in tumor tissue samples was analyzed with immunohistochemistry (IHC) using the Dako pharmDx IHC assay. EGFR and mRNA expression from the EGFR ligands epiregulin (EREG) and amphiregulin (AREG) were measured using next-generation RNA sequencing (RNAseq). Results: As of 29 March 2017, 42 pts were treated (13 colon, 5 head & neck [H&N] cancer, 5 non-small cell lung cancer, 5 GBM, 2 breast, 12 other). Ten dose escalation cohorts have been completed with the last cleared dose 4.5 mg/kg per cycle. The most common adverse events were infusion reactions in 19/42 pts (45%) and fatigue in 17/42 pts (41%). Sixteen pts (38%) had stable disease (SD), including 4 pts who remained on study longer than 6 months. All markers are expressed in a wide range across enrolled pts. The pts with response had high EGFR and EGFR ligand. One pt with head and neck cancer who received 5 cycles of ABBV-221 had a partial response and elevated levels of both EGFR (3-fold higher than median for all pts) and EGFR ligand (8-fold higher AREG and 19-fold higher EREG than median for all pts). One colorectal cancer pt with durable SD >6 months had high levels of ligand (EREG) but not receptor, and one H&N pt with SD >6 months had high levels of EGFR receptor but not ligand. Conclusions: Multiple EGFR pathway status biomarkers were evaluated and correlated with clinical outcomes observed in this phase 1 trial of ABBV-221. Patients who observed clinical benefit had high levels of EGFR pathway markers. The duration of SD in pts with refractory solid tumors is encouraging. Clinical trial information: NCT02365662 Citation Format: Emiliano Calvo, James M. Cleary, Victor Moreno, Maryella Gifford, Lisa Roberts-Rapp, Peter J. Ansell, Ho-Jin Lee, Beibei Hu, David Barch, Christopher Ocampo, Anthony W. Tolcher. Biomarker analysis in a phase 1 study of the antibody-drug conjugate ABBV-221 in patients with solid tumors likely to overexpress the epidermal growth factor receptor (EGFR) [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A028.

Fraser S, Roberts L, Murphy E. Cauda equina syndrome: a literature review of its definition and clinical presentation. Objective To review the current evidence for the signs and symptoms of cauda equina syndrome (CES). Data Sources Relevant literature sourced through Medline, Embase, and CINAHL using the key search words "cauda equina syndrome" combined with "definition," "clinical presentation," "signs and symptoms," "pathology," and "etiology." Study Selection Not applicable. Data Extraction Not applicable. Data Synthesis Three reviewers independently extracted data on CES from the literature specific to its definition, clinical presentation, and etiology. Of 111 articles, 105 were included for review, and relevant information on CES was synthesized into a framework structured as per a clinical consultation. A content analysis was then conducted using the method adopted by the Chartered Society of Physiotherapy whereby the level of consensus for each sign and symptom of CES was determined by its percentage coverage within the literature: 100% coverage equals unanimity, 75% to 99% equals consensus, 51% to 74% equals majority view, and 0% to 50% equals no consensus. This enabled the frequency of each reported sign and symptom to be ranked. Articles that included specific definitions for CES were divided into 3 categories: those that (1) included generalized statements, (2) stated a pathomechanical basis, and (3) defined the syndrome by its clinical presentation. Throughout this review, the frequencies of specific etiologies and pathologies were noted. Together with details of clinical presentation, this enabled a comprehensive review of CES. No single aspect of CES within the literature achieved unanimity or consensus; however, a majority view indicated that there would be bladder and sensory disturbance (74% and 66% of all articles, respectively). The most commonly cited pathology resulting in CES was identified as the disk (45% of all articles reviewed). Conclusions There are marked inconsistencies in the current evidence base surrounding the etiology and clinical presentation of CES, with 17 definitions identified. Subclassifications of the definition of CES are ambiguous and should be avoided. From reviewing 105 articles, a single definition of CES is proposed. For a diagnosis of CES, one or more of the following must be present: (1) bladder and/or bowel dysfunction, (2) reduced sensation in the saddle area, and (3) sexual dysfunction, with possible neurologic deficit in the lower limb (motor/sensory loss, reflex change).

The detection of circulating tumor cells (CTCs) in peripheral blood may have important prognostic and predictive implications in breast cancer treatment. A limitation in this field has been the lack of a validated method of accurately measuring CTCs. While sensitivity has improved using RT-PCR, specificity remains a major challenge. The goal of this paper is to present a sensitive and specific methodology of detecting CTCs in women with HER-2 positive metastatic breast cancer, and to examine its role as a marker that tracks disease response during treatment with trastuzumab-containing regimens. The study included patients with HER-2-positive metastatic breast cancer enrolled on two different clinical protocols using a trastuzumab-containing regimen. Serial CTCs were measured at planned time points and clinical correlations were made. Immunomagnetic selection of circulating epithelial cells was used to address the specificity of tumor cell detection using cytokeratin 19 (CK19). In addition, the extracellular domain of the HER-2 protein (HER-2/ECD) was measured to determine if CTCs detected by CK19 accurately reflect tumor burden. The presence of CTCs at first restaging was associated with disease progression. We observed an association between CK19 and HER-2/ECD. The association of HER-2/ECD with clinical response followed a similar pattern to that seen with CK19. Finally, the absence of HER-2/ECD at best overall response and a change of HER-2/ECD from positive at baseline to negative at best overall response was associated with favorable treatment response. Our study supports the prognostic and predictive role of the detection of CTCs in treatment of HER-2-positive metastatic breast cancer patients. The association between CK19 and markers of disease burden is in line with the concept that CTCs may be a reliable measure of tumor cells in the peripheral blood of patients with metastatic breast cancer. The association of CTCs at first restaging with treatment failure indicates that CTCs may have a role as surrogate markers to monitor treatment response.

Mutations in the RP2 gene account for up to 20% of X-linked recessive retinitis pigmentosa (RP). Arg120stop is to date the most frequently reported mutation found in RP2. Mutation screening was performed during the course of a large screening program of retinal degenerative disorders (RDDs) in South Africa using exon 1 and 2 of RP2 in 20 unrelated families with an X-linked mode of retinal degenerative inheritance. Direct sequencing analysis revealed a C-->T transition at position 358 in the proband in a family of German origin. Subsequent analysis revealed that this Arg120stop mutation cosegregated with the disease in an additional affected family member. The nonsense mutation, Arg120stop, could not however, be detected in the somatic cells of the obligate carrier female. This, the first report of a germ line mutation for a family with RP, has many implications for genetic counseling of retinal degeneration (RD). To avoid inaccurate risk assessment for RP due to epigenetic events, such as the rare occurrence of germ line mosaicism, genetic counseling in families with XLRP should always be guided by molecular testing.

Analysis of exon ORF15 of the RPGR gene has revealed a novel mutation in a South African family with X-linked retinitis pigmentosa (XLRP), which has implications for the rest of the family in terms of pre-symptomatic testing. The ability to test for this mutation will be beneficial for the accurate determination of carrier status in female relatives who may have been unaware of their risk before this study was performed. This work also highlights the need to be aware of the ramifications of mutation testing in what may appear to be small families. This is the first report of an RPGR ORF15 mutation in a South African family of mixed ancestry.

The anti-apoptotic proteins BCL-2 and MCL-1 have been shown to promote multiple myeloma (MM) cell survival. Venetoclax (VEN) is a potent, selective, and orally bioavailable small-molecule inhibitor of BCL-2. Bortezomib (BTZ) is a proteasome inhibitor that can inhibit MCL-1 activity by increasing the MCL-1 antagonist, NOXA. Results presented herein describe correlative biomarker analyses in the ongoing phase 1b study of VEN in combination with BTZ and dexamethasone in patients with relapsed/refractory (R/R) MM (NCT01794507). As of 19 Aug 2016, 66 patients were enrolled on study. Baseline bone marrow aspirate samples were available from 52 patients, of which 45 were evaluable for BCL-2 family gene expression by droplet digital PCR in CD138-selected tumor cells. Correlation between BCL2 (BCL-2), BCL2L1 (BCL-XL) and MCL1 (MCL-1) mRNA expression (log2-transformed copies/ul normalized to housekeeping gene) and preliminary efficacy [overall response rate (ORR), time to disease progression (TTP) and duration of response (DoR)] were examined by Log-rank and Wilcoxon tests for binary biomarkers, and by risk ratio from Cox proportional hazard model for continuous biomarkers. The ORR was 68% (44/65) for all evaluable patients and 89% (31/35) in patients who had 1-3 prior therapies (31/35). A broad range of BCL2, BCL2L1 and MCL1 expression was observed, however higher BCL2 levels were detected in patients who achieved a partial response (PR) or better (median: 3.01 vs 0.87, p Citation Format: Jeremy Ross, Brenda Chyla, Rasna Goswami, Lisa Roberts-Rapp, Yan Sun, Yanwen Jiang, Elizabeth Punnoose, Maria Verdugo, Anahita Bhathena, Paulo Maciag. BCL2 expression is a potential predictive biomarker of response to venetoclax in combination with bortezomib and dexamethasone in patients with relapsed/refractory multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT122. doi:10.1158/1538-7445.AM2017-CT122

Selective BCL-2 targeting with venetoclax (VEN) has shown potent anti-tumor activity in human multiple myeloma (MM) cell lines and primary MM cells harboring the t(11;14) translocation, which is present in approximately 15-20% of patients (pts) with MM. Preclinical studies also indicated that VEN single-agent activity correlated with higher expression levels of BCL-2 relative to BCL-XL and MCL-1. The results presented herein describe correlative biomarker analyses in the ongoing phase 1 study of VEN monotherapy in pts with relapsed/refractory (R/R) MM (NCT01794520). As of 19 Aug 2016, 66 pts were enrolled on study, including 30 pts with t(11;14) MM as determined by interphase FISH analysis on CD138-selected bone marrow plasma cells. The overall response rate (ORR) in pts with t(11;14) MM was 40%, compared to 6% in the non-t(11;14) group (n=36). Responses in t(11;14) pts were durable, with a median duration of response (DoR) of 9.7 months and a median time to progression (TTP) of 6.6 months. In contrast, the median TTP was 1.9 months for non-t(11;14) pts. VEN activity was independent of refractory status to prior therapies and clinical responses were observed in t(11;14) pts with concurrent high-risk cytogenetics, including chromosome 17p deletion. In addition to cytogenetic analyses, baseline bone marrow aspirate samples from 44 pts were evaluable for BCL2 (BCL-2), BCL2L1 (BCL-XL) and MCL1 (MCL-1) mRNA expression by droplet digital PCR. Gene expression analysis revealed that the ratios of BCL2:BCL2L1 (log2 median: 2.75 vs 0.56, p low BCL2L1 > high BCL2:MCL1 > high BCL2 > low MCL1. On the basis of these results, bootstrapping and aggregating thresholds from trees was used to estimate a threshold value for BCL2:BCL2L1 that would provide optimum selection of pts likely to have a response. A high BCL2:BCL2L1 expression ratio (≥5.0) was observed in 10/44 (23%) pts, and was enriched in the t(11;14) subgroup [9/24 (38%) vs 1/20 (5%) in the non-t(11;14) subgroup]. Within the t(11;14) group, 8/9 pts with a high BCL2:BCL2L1 expression ratio achieved a partial response or better (ORR 88%), with a median DoR of 9.7 months and median TTP of 11.5 months. Median TTP for t(11;14) pts (n=15) with a low BCL2:BCL2L1 ratio was 5.3 months. Commensurate with preclinical findings, VEN has promising single-agent activity in pts with R/R t(11;14) MM. Additionally, BCL-2 family expression profiling can further define clinical activity within t(11;14) pts, including 88% ORR in high BCL2:BCL2L1 expressors, thus providing further supportive evidence for VEN monotherapy as a unique biomarker-driven approach for MM treatment. Citation Format: Jeremy Ross, Brenda Chyla, Rasna Goswami, Lisa Roberts-Rapp, Yan Sun, Yanwen Jiang, Elizabeth Punnoose, Maria Verdugo, Anahita Bhathena, Paulo Maciag. Correlative biomarkers of response to venetoclax monotherapy in patients with relapsed/refractory multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT121. doi:10.1158/1538-7445.AM2017-CT121

2003 Background: GBM is the most common malignant primary brain tumor in adults. Pts with rGBM have a poor prognosis. EGFR is amplified (amp) in ~50% of GBMs and is a compelling therapeutic target. ABT-414 is an antibody-drug conjugate composed of an EGFR-directed antibody conjugated to a microtubule toxin, MMAF. ABT-414 binds a unique epitope exposed during EGFR activation, either through ligand stimulation or mutation such as EGFR variant III (EGFRvIII), releasing MMAF into the cancer cell. Here, we report a pooled safety and efficacy analysis of ABT-414 +/- TMZ in EGFR amp, rGBM. Methods: M12-356 is a Phase 1, open-label, multi-arm study. Results from the 2 arms accruing rGBM pts were pooled for analysis. Eligible adults had rGBM, centrally confirmed EGFR amp, and KPS ≥ 70. Pts received 0.5-1.25 mg/kg ABT-414 on days 1 and 15 +/- 150-200 mg/m2 TMZ on days 1-5 of 28-day cycles until progression (per RANO). Results: As of 11 January 2017, 126 pts were treated. The most common adverse events (AEs, ≥ 25% pts) were ocular (90%) and included blurred vision (64%) and photophobia (31%), which were mainly reversible. Common non-ocular AEs were fatigue (36%) and headache (30%). Grade 3/4 AEs (≥ 5% pts) included ocular toxicities (29%) and decreased platelets/thrombocytopenia (10%). Serious AEs included seizure and keratitis (2% each). Of 125 pts evaluable by RANO, 52% had improvement or stabilization as best response (2 CR, 9 PR, 54 SD), and the remaining 60 (48%) had PD. Of 115 pts with measurable disease at baseline, the objective response rate (ORR) was 10% (2 CR + 9 PR). For 5 pts, re-resection for radiographic PD revealed mostly necrotic tissue and pts were classified as SD, suggesting the ORR may be an underestimate. Of all 126 pts, the 6-month PFS rate (PFS6) was 26%; median OS was 8.5 months. Conclusions: In this Phase 1 trial of EGFR amp, rGBM, we observed encouraging disease control (52%, CR + PR + SD) and PFS6 (26%) rates. Toxicity was mainly ocular, and reversible. A global, randomized trial of ABT-414 vs. ABT-414 + TMZ vs. TMZ/lomustine in EGFR amp, rGBM has completed accrual with results expected later this year (NCT02343406). Clinical trial information: NCT01800695.

2510 Background: ABBV-221 is a 2nd-generation antibody-drug conjugate (ADC) targeting EGFR based on the 1st-generation ADC ABT-414. ABT-414 shows efficacy in glioblastoma (GBM) patients (pts) with EGFR amplification in ongoing studies. ABBV-221 is an affinity matured monoclonal antibody against EGFR linked to the toxin MMAE. ABBV-221 has higher affinity for overexpressed EGFR than ABT-414, potentially allowing it to target a broader range of tumor types. Methods: This is a Phase 1, multicenter study to determine maximum tolerated dose (MTD) and recommended Phase 2 dose (RPTD) of ABBV-221. Pts are required to have an EGFR-dependent cancer to be eligible. Starting dose of ABBV-221: 0.3 mg/kg IV infused over 3 hrs for each 21-day cycle, with alternate dosing schedules utilized (2 wks on, 1 wk off or weekly) to mitigate infusion reactions. Results: As of 11 January 2017, 42 pts were treated (13 colon, 5 head & neck (H&N) cancer, 5 non-small cell lung cancer, 5 GBM, 2 breast, 12 other). Ten dose escalation cohorts have been completed with the last cleared dose 4.5 mg/kg per cycle. Tumor tissue samples were evaluated for EGFR protein expression by IHC, EGFR and EGFR ligand mRNA expression by RNAseq, and the results compared to outcome. The most common adverse event (AE) was infusion reaction in 18/42 pts (43%); 3 pts experienced severe infusion reactions. Several mitigation strategies were used to permit continued dose escalation. The other most common AE was fatigue in 17/42 pts (41%). Only 1 pt had keratitis (Grade 4). Sixteen pts (38%) had stable disease (SD), including 4 pts who remained on study longer than 6 months. One H&N pt who has received 2 cycles of ABBV-221 had an unconfirmed partial response and continues to be treated. This pt had high levels of both EGFR and EGFR ligand. Preliminary pharmacokinetics (PK) analysis suggests ABBV-221 exposures are approximately dose-proportional. Conclusions: Safety, PK, pharmacodynamics, and preliminary efficacy data of ABBV-221 warrant further study in this population. Infusion reactions have been manageable and primarily a first dose phenomenon. The duration of SD in pts with refractory solid tumors is encouraging. Clinical trial information: NCT02365662.

The mammaglobin gene has been shown to be preferentially expressed in breast tissue. Few genes match its specificity. Mammaglobin has generated much interest, and studies are ongoing to develop diagnostic tests for breast cancer based on the detection of mammaglobin. While searching the Incyte Genomics Lifeseq database for tissue-specific markers, we observed a second secretoglobin, BU101, also known as lipophilin B. We report here that mammaglobin, in breast tissue, is found as a complex with BU101. The complex was isolated from breast cancer tissue and was characterized as the biologically relevant form of mammaglobin.

Stargardt disease is an ABCA4-associated retinopathy, which generally follows an autosomal recessive inheritance pattern and is a frequent cause of macular degeneration in childhood. ABCA4 displays significant allelic heterogeneity whereby different mutations can cause retinal diseases with varying severity and age of onset. A genotype–phenotype model has been proposed linking ABCA4 mutations, purported ABCA4 functional protein activity and severity of disease, as measured by degree of visual loss and the age of onset. It has, however, been difficult to verify this model statistically in observational studies, as the number of individuals sharing any particular mutation combination is typically low. Seven founder mutations have been identified in a large number of Caucasian Afrikaner patients in South Africa, making it possible to test the genotype–phenotype model. A generalised linear model was developed to predict and assess the relative pathogenic contribution of the seven mutations to the age of onset of Stargardt disease. It is shown that the pathogenicity of an individual mutation can differ significantly depending on the genetic context in which it occurs. The results reported here may be used to identify suitable candidates for inclusion in clinical trials, as well as guide the genetic counselling of affected individuals and families.

Bromodomain and extra-terminal (BET) family are dual bromodomain-containing proteins that play an important role in transcription regulation. ABBV-075 is a small molecule BET bromodomain inhibitor currently in phase 1 clinical trials. Here we report the identification of Hexim1 and other BET-responsive genes as robust pharmacodynamic markers for monitoring ABBV-075 target engagement in tumors and in surrogate tissues such as whole blood and skin. Transcription profiling of cancer cell lines for their responses to BET inhibitors identified a set of 9 BET-regulated genes, including Hexim1, that responded to BET inhibition across cancer cell lines and in xenograft tumors. Further characterization of BET-responsive genes in surrogate tissues such as mouse skin, mouse/human PBMCs and whole blood revealed that the mRNA level of Hexim1 exhibited the best response to BETi treatment across different settings. A dose-dependent increase of Hexim1 expression was detected in the whole blood of ABBV-075 treated tumor bearing mice, and the Hexim1 response was closely correlated with the plasma drug concentration and largely reflected the anti-tumor efficacy at various dose levels of ABBV-075. Hexim1 is part of a protein/RNA complex that sequesters pTEFb and prevents its recruitment by BRD4. It also reportedly mediates the anti-proliferative activity of BRD4 in AML. Taken together, Hexim1 could serve as a functional relevant pharmacodynamic marker for monitoring ABBV-075 target engagement in animal models and in the clinical setting. Citation Format: Xiaoli Huang, Xiaoyu Lin, Leiming Li, Rongqi Wang, Lisa Roberts, Paul Hessler, Tamar Uziel, Lloyd Lam, Terry Magoc, Daniel H. Albert, Steven W. Elmore, Guowei Fang, Saul H. Rosenberg, Keith McDaniel, Warren Kati, Yu Shen. HEXIM1 as a pharmacodynamic marker for monitoring target engagement of ABBV-075. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3770.

Retinal degenerative disorders (RDDs) encompass a group of inherited diseases characterised by vision loss. The genetic and clinical complexity poses a challenge in unravelling the molecular genetic aetiology of this group of disorders. Furthermore, the population diversity in South Africa (SA) presents researchers with a particularly complicated task. Rapid advances in the development of cutting-edge technological platforms over the past two decades, however, have assisted in overcoming some of the challenges. The RDD research team has utilised these escalating technologies, which has facilitated a corresponding increase in molecular diagnoses. A biorepository has been established and comprises ~3 200 patient DNA samples archived with many forms of RDD (including retinitis pigmentosa, macular dystrophies, Stargardt disease, Leber congenital amaurosis, Usher syndrome and Bardet Biedl syndrome). A comprehensive review is presented of the SA journey spanning 25 years, into elucidating the molecular genetic basis of various forms of RDD in SA.

Introduction: Multiple myeloma (MM) tumor cell survival is largely dependent on a complex network of interactions between pro-survival (BCL-2, BCL-XL, MCL-1) and pro-death (BIM, NOXA, BID, BAD, BAK, BAX) BCL-2 family members. Venetoclax (VEN) is a potent, selective, orally bioavailable small-molecule BCL-2 inhibitor. Bortezomib (BTZ) is a proteasome inhibitor that can impede MCL-1 activity by increasing the MCL-1 antagonist NOXA. The addition of VEN has been shown to enhance the activity of BTZ in MM cell line and xenograft models. Chromosomal abnormalities (immunoglobulin heavy chain translocations, amplification, deletions) can also influence sensitivity of MM cells to treatment. Results presented herein describe retrospective biomarker analysis in a subset of dose-escalation patients (pts) from an ongoing phase 1b study of VEN in combination with BTZ and dexamethasone in relapsed/refractory (R/R) MM. Methods: Exploratory objectives included evaluation of chromosomal abnormalities, BCL-2 family member gene expression levels, and ex vivosensitivity of pt MM tumor cells to VEN and/or BTZ. Interphase FISH analysis was performed on CD138-positively selected bone marrow mononuclear cells (BMMC) using probes for t(11;14), t(4;14), deletion 17p (17p-), deletion 13q (13q-), and amplification of chromosomes 5, 9, or 15 (denoted as hyperdiploid [HY]). Absolute quantitation of BCL-2 family members (BCL-2, BCL-XL, MCL-1, BCL-2A1, BIM, BID, BAD, BAX, and NOXA) was performed on CD138-selected BMMCs collected at baseline using TaqMan probe-based droplet digital polymerase chain reaction. Ex vivosensitivity of BMMCs collected at baseline to increasing doses of VEN and/or BTZ was determined by flow cytometry using a combined analysis for the loss of CD138 surface expression and the alteration of cellular morphology (lower FCS). Correlations between biomarkers and median best percentage change in M-protein were examined by Spearman test. Correlations between biomarkers and median time on study (mToS) were examined by log-rank and Wilcoxon tests for binary biomarkers, and by risk ratio from a Cox proportional hazard model for continuous biomarkers. No correction for multiple testing was performed. Results: Forty-one pts were enrolled as of 06/15/2015. The biomarker study subgroups were similar to the overall pt population with respect to demographics. Of the 37/41 (90%) pts assessed by FISH, 5 were t(11;14), 3 were t(4;14), 20 were 13q-, 10 were 17p-, and 15 were HY. In pts with HY, median best percentage change in M-protein was -79.4% compared to +101.65% in non-HY, while mToS was 309 days compared to 29 days in non-HY (p Conclusions: VEN in combination with BTZ and dexamethasone is active in R/R MM. CD138-enriched BMMCs were obtained in sufficient numbers to enable downstream FISH analysis, BCL-2 family gene expression profiling, and ex vivo sensitivity evaluation. The exploratory biomarker analysis showed that higher BCL-2 gene expression levels at baseline significantly correlated with clinical responses to therapy, with a trend toward increased mToS. Additionally, MM cells treated ex vivo demonstrated greater sensitivity to the combination of VEN/BTZ than to the 2 single agents alone. Further investigation of this dataset continues, including analysis of on-treatment tumor samples in a subset of pts. Disclosures Ross: AbbVie: Employment, Equity Ownership. Off Label Use: Venetoclax is an investigational drug that is not yet approved in this indication.. Chyla:AbbVie: Employment, Equity Ownership. Roberts-Rapp:AbbVie: Employment, Equity Ownership. Goswami:AbbVie: Employment, Equity Ownership. Yan:AbbVie: Employment, Equity Ownership. Huang:AbbVie: Employment, Equity Ownership. Bhathena:AbbVie: Employment, Equity Ownership. Enschede:AbbVie: Employment, Equity Ownership. Maciag:AbbVie: Employment, Equity Ownership. Humerickhouse:AbbVie: Employment, Equity Ownership. McKeegan:AbbVie: Employment, Equity Ownership.

As a population, non-Hodgkin’s lymphoma (NHL) cell lines positive for the t(14;18) translocation and/or possessing elevated BCL2 copy number (CN; BCL2High) are exquisitely sensitive to navitoclax or the B-cell lymphoma protein-2 (BCL-2)-selective inhibitor venetoclax. Despite this, some BCL2High cell lines remain resistant to either agent. Here we show that the MCL-1-specific inhibitor A-1210477 sensitizes these cell lines to navitoclax. Chemical segregation of this synergy with the BCL-2-selective inhibitor venetoclax or BCL-XL-selective inhibitor A-1155463 indicated that MCL-1 and BCL-2 are the two key anti-apoptotic targets for sensitization. Similarly, the CDK inhibitor flavopiridol downregulated MCL-1 expression and synergized with venetoclax in BCL2High NHL cell lines to a similar extent as A-1210477. A-1210477 also synergized with navitoclax in the majority of BCL2Low NHL cell lines. However, chemical segregation with venetoclax or A-1155463 revealed that synergy was driven by BCL-XL inhibition in this population. Collectively these data emphasize that BCL2 status is predictive of venetoclax potency in NHL not only as a single agent, but also in the adjuvant setting with anti-tumorigenic agents that inhibit MCL-1 function. These studies also potentially identify a patient population (BCL2Low) that could benefit from BCL-XL (navitoclax)-driven combination therapy.

Background Detection of circulating tumor cells (CTC) in the blood of cancer patients may have prognostic and predictive significance. However, background expression of 'tumor specific markers' in peripheral blood mononuclear cells (PBMC) may confound these studies. The goal of this study was to identify the origin of Cytokeratin 19 (CK19) and HER-2 signal in PBMC and suggest an approach to enhance techniques involved in detection of CTC in breast cancer patients. Methods PBMC from healthy donors were isolated and fractionated into monocytes, lymphocytes, natural killer cells/granulocytes and epithelial populations using immunomagnetic selection and fluorescent cell-sorting for each cell type. RNA isolated from each fraction was analyzed for CK19, HER2 and Beta 2 microglobulin (B2M) using real-time qRT-PCR. Positive selection for epithelial cells and negative selection for NK/granulocytes were used in an attempt to reduce background expression of CK19 and HER2 markers. Results In normal PBMC, CK19 was expressed in the lymphocyte population while HER-2 expression was highest in the NK/granulocyte population. Immunomagnetic selection for epithelial cells reduced background CK19 signal to a frequency of Conclusion We present a novel method to improve the specificity of the traditional method of detecting CTC by identifying the source of the background signals and reducing them by negative immunoselection. Further studies are warranted to improve sensitivity and specificity of methods of detecting CTC will prove to be useful tools for clinicians in determining prognosis and monitoring treatment responses of breast cancer patients.

Mutation analysis of retinal candidate genes is performed as part of an ongoing research to identify the causative genetic defect in South African families with retinal degenerative disorders (RDDs). A translational research protocol has been established whereby probands are counseled and given their molecular genetic results to take back to other family members, who can then request individual diagnostic testing. A Thr17Met mutation of the rhodopsin gene was identified in a Caucasian South African family with autosomal dominant retinitis pigmentosa. Patients with this mutation appear to benefit from treatment using oral vitamin A supplementation. This family has been informed that a molecular diagnosis is available; however, one individual has refused testing and none of the younger generation has shown interest in receiving molecular results or genetic counseling. Adapting the established protocol for the translation of RDD research results and contacting mutation positive individuals may be justifiable in light of the potential benefit of therapy.

2510 Background: Aberrant EGFR expression and signaling has been identified as a hallmark of cancer growth and survival. ABT-414 is an antibody-drug conjugate composed of the antibody ABT-806, targ...

ABT-199 is a first-in-class orally bioavailable BCL-2 selective inhibitor that is currently being testing in clinical trials. Clinical activity has been reported in chronic lymphocytic leukemia and NHL patients treated with ABT-199 as a monotherapy. As with any targeted cancer therapy, it is important to identify the potential mechanisms of resistance, not only to inform patient selection but also to develop strategies to circumvent resistance as it emerges. In this study, we generated resistant variants from ABT-199-sensitive cell lines of different leukemia and lymphoma subtypes (two diffuse large B-cell lymphomas, two follicular lymphomas, one leukemia line, and two mantle cell lymphomas) by increasing exposure to ABT-199 in a stepwise manner over time. Compared to the parental cell lines, the variants were 10 to >100-fold less sensitive to ABT-199. The ABT-199-resistant variants were also resistant to ABT-263 (navitoclax), a BCL-2/BCL-XL inhibitor, as well as to other standard-of-care cancer agents. Gene and protein expression analyses revealed multiple alterations in the expression of BCL-2 family members in the resistant variants; however, not all of the changes were universal. Alterations included changes in the levels of the target protein BCL-2, reduction of the pro-apoptotic proteins BAX, BIM or NOXA, or increases in the anti-apoptotic proteins BCL-XL or MCL-1. In some but not all cases, the changes to gene and protein expression levels were accompanied by changes in DNA copy number. To determine whether changes in the anti-apoptotic BCL-2 family members were causally related to ABT-199 resistance, we tested ABT-199 in combination with BCL-XL and MCL-1 selective inhibitors. Co-treating with ABT-199 and either a BCL-XL or MCL-1 selective compound was synergistic in killing the ABT-199-resistant variants, suggesting these proteins can both contribute directly to ABT-199 resistance. Under appropriate selection pressure, intrinsic traits that mitigate the effects of anticancer drugs can lead to the enrichment of a resistant tumor population. In ABT-199-resistant RS4;11 cells we observed a complete and permanent loss of BAX, one of the ultimate effectors of mitochondrial mediated apoptosis. FACS analysis revealed that there was a pre-existing population of RS4;11 cells lacking this protein. It is likely that these cells had a selective advantage over those expressing BAX when treated with ABT-199. Overall our data indicate that there are distinct mechanisms of resistance to ABT-199, either innate or acquired, which will have important implications for both patient selection and developing strategies to overcome resistance. Disclosures: All authors are employees of AbbVie. The design, study conduct, and financial support for the research were provided by AbbVie. AbbVie participated in the interpretation of data, review, and approval of the publication. Citation Format: Stephen K. Tahir, Morey L. Smith, Paul Hessler, Lisa Roberts-Rapp, Joel D. Leverson, Lloyd T. Lam. Mechanisms of resistance to ABT-199 in leukemia and lymphoma cell lines. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Drug Sensitivity and Resistance: Improving Cancer Therapy; Jun 18-21, 2014; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(4 Suppl): Abstract nr B30.

'Plateau' is an expression frequently used in relation to decisions to discharge patients from physiotherapy following stroke. This paper critically considers the concept of recovery plateau in stroke, exploring (i) the evidence for plateau, (ii) potential contributing factors, and (iii) the consequences for patients, therapists and services.The concept of recovery plateau in stroke was reviewed drawing on standard critical appraisal methodology for the search strategy and critique. Electronic searches using Web of Knowledge, MEDLINE, CINAHL, Department of Health Website and the Cochrane Library from the earliest dates of coverage until February 2005 identified quantitative and qualitative literature related to stroke, plateau, recovery, outcome, rehabilitation and physiotherapy.The concept of plateau is ambiguous. Recovery has been considered to plateau within the first 6 months, yet recent studies indicate later recovery is possible. We suggest that 'plateau' relates not only to the patient's physical potential, but is influenced by how recovery is measured, the intensity and type of therapy, patients' actions and motivations, therapist values, and service limitations.'Plateau' is conceptually more complex than previously considered. Current conceptualizations may limit potential recovery and hinder service development. Research into plateau which takes account of contextual issues of therapy provision is required.

Genetic and physical mapping of the RP17 locus on 17q identified a 3.6-megabase candidate region that includes the gene encoding carbonic anhydrase IV ( CA4 ), a glycosylphosphatidylinositol-anchored protein that is highly expressed in the choriocapillaris of the human eye. By sequencing candidate genes in this region, we identified a mutation that causes replacement of an arginine with a tryptophan (R14W) in the signal sequence of the CA4 gene at position -5 relative to the signal sequence cleavage site. This mutation was found to cosegregate with the disease phenotype in two large families and was not found in 36 unaffected family members or 100 controls. Expression of the mutant cDNA in COS-7 cells produced several findings, suggesting a mechanism by which the mutation can explain the autosomal dominant disease. In transfected COS-7 cells, the R14W mutation ( i ) reduced the steady-state level of carbonic anhydrase IV activity expressed by 28% due to a combination of decreased synthesis and accelerated turnover; ( ii ) led to up-regulation of immunoglobulin-binding protein, double-stranded RNA-regulated protein kinase-like ER kinase, and CCAAT/enhancer-binding protein homologous protein, markers of the unfolded protein response and endoplasmic reticulum stress; and ( iii ) induced apoptosis, as evidenced by annexin V binding and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining, in most cells expressing the mutant, but not the WT, protein. We suggest that a high level of expression of the mutant allele in the endothelial cells of the choriocapillaris leads to apoptosis, leading in turn to ischemia in the overlying retina and producing autosomal dominant retinitis pigmentosa.

Having identified a disease-associated rhodopsin mutation in a patient with retinitis pigmentosa (RP), the issue is to address the question of whether to offer genetic testing to at-risk family members. Two members of a South African (SA) family, one of whom suffers from RP, as well as 54 unrelated SA RP patients from the same population group were investigated using single-stranded conformational polymorphism analysis followed by DNA sequencing. A rare homozygous mutation at the intron-exon boundary of exon 4 in the rhodopsin gene was identified in the proband. One of his siblings was found to be heterozygous for the same mutation. The mutation was not detected in the 54 unrelated SA RP patients examined, 11 of whom were sporadic cases. A low incidence of RP amongst heterozygous carriers of this mutation has been reported; however, in the past it has been unclear whether the mutation has an effect in single copy or dual copy. To the best of our knowledge, this is the first time that this mutation has been reported as homozygous in an affected individual, thereby resolving the issue and confirming that it is a recessive disease-associated mutation. This is also the first autosomal recessive RP disease-causing rhodopsin mutation that has been identified in Southern Africa. Analysis of the extended pedigree indicated obligate heterozygous carriers of the mutation, without obvious signs of visual impairment in early adulthood. The extent to which potential heterozygous carriers should be pursued and clinically examined is discussed and the question is addressed as to whether to inform the family of these molecular findings.

2021 Background: Patients (pts) with recurrent GBM have few treatment options and a very poor prognosis. GBM tumors often exhibit aberrant epidermal growth factor receptor (EGFR) proliferative sign...