AML cells have low spare reserve capacity in their respiratory chain that renders them susceptible to oxidative metabolic stress.

Mitochondrial respiration is a crucial component of cellular metabolism that can become dysregulated in cancer. Compared with normal hematopoietic cells, acute myeloid leukemia (AML) cells and patient samples have higher mitochondrial mass, without a concomitant increase in respiratory chain complex activity. Hence these cells have a lower spare reserve capacity in the respiratory chain and are more susceptible to oxidative stress. We therefore tested the effects of increasing the electron flux through the respiratory chain as a strategy to induce oxidative stress and cell death preferentially in AML cells. Treatment with the fatty acid palmitate induced oxidative stress and cell death in AML cells, and it suppressed tumor burden in leukemic cell lines and primary patient sample xenografts in the absence of overt toxicity to normal cells and organs. These data highlight a unique metabolic vulnerability in AML, and identify a new therapeutic strategy that targets abnormal oxidative metabolism in this malignancy.

A classification system for clinical relevance of somatic variants identified in molecular profiling of cancer.

PURPOSE: Interpretation systems for clinical laboratory reporting of genetic variants for inherited conditions have been widely published. By contrast, there are no existing systems for interpretation and classification of somatic variants found from molecular testing of cancer. METHODS: We designed an assessment protocol and classification system for somatic variants identified through next-generation sequencing molecular profiling of tumor-derived samples and applied these to a pilot dataset of somatic variants found by next-generation sequencing profiling of 158 tumor samples derived from advanced cancer patients examined at the Princess Margaret Cancer Centre. RESULTS: We present a classification system to interpret the significance of genetic variants in molecular analysis of cancer, including the following key factors: (i) known or predicted pathogenicity of the variant; (ii) primary site and tumor histology in which the variant is found; (iii) recurrence of the variant; and (iv) evidence of clinical actionability. We used these factors to develop a five-category somatic variant classification for simplified reporting of variant interpretations to treating oncologists. CONCLUSION: Our somatic variant classification can be of practical value to other clinical molecular laboratories performing cancer genetic profiling by promoting consistent reporting of somatic variants and permitting harmonization of variant data among laboratories and clinical studies.

Carnitine transporter CT2 (SLC22A16) is over-expressed in acute myeloid leukemia (AML) and target knockdown reduces growth and viability of AML cells.

AML (acute myeloid leukemia) cells have a unique reliance on mitochondrial metabolism and fatty acid oxidation (FAO). Thus, blocking FAO is a potential therapeutic strategy to target these malignant cells. In the current study, we assessed plasma membrane carnitine transporters as novel therapeutic targets for AML. We examined the expression of the known plasma membrane carnitine transporters, OCTN1, OCTN2, and CT2 in AML cell lines and primary AML samples and compared expression to normal hematopoietic cells. Of the three carnitine transporters, CT2 demonstrated the greatest differential expression between AML and normal cells. Using shRNA, we knocked down CT2 and demonstrated that target knockdown impaired the function of the transporter. In addition, knockdown of CT2 reduced the growth and viability of AML cells with high expression of CT2 (OCI-AML2 and HL60), but not low expression. CT2 knockdown reduced basal oxygen consumption without a concomitant increase in glycolysis. Thus, CT2 may be a novel target for a subset of AML.

Select microtubule inhibitors increase lysosome acidity and promote lysosomal disruption in acute myeloid leukemia (AML) cells.

To identify new biological vulnerabilities in acute myeloid leukemia, we screened a library of natural products for compounds cytotoxic to TEX leukemia cells. This screen identified the novel small molecule Deoxysappanone B 7,4' dimethyl ether (Deox B 7,4), which possessed nanomolar anti-leukemic activity. To determine the anti-leukemic mechanism of action of Deox B 7,4, we conducted a genome-wide screen in Saccharomyces cerevisiae and identified enrichment of genes related to mitotic cell cycle as well as vacuolar acidification, therefore pointing to microtubules and vacuolar (V)-ATPase as potential drug targets. Further investigations into the mechanisms of action of Deox B 7,4 and a related analogue revealed that these compounds were reversible microtubule inhibitors that bound near the colchicine site. In addition, Deox B 7,4 and its analogue increased lysosomal V-ATPase activity and lysosome acidity. The effects on microtubules and lysosomes were functionally important for the anti-leukemic effects of these drugs. The lysosomal effects were characteristic of select microtubule inhibitors as only the Deox compounds and nocodazole, but not colchicine, vinca alkaloids or paclitaxel, altered lysosome acidity and induced lysosomal disruption. Thus, our data highlight a new mechanism of action of select microtubule inhibitors on lysosomal function.

A randomized phase II study of cediranib alone versus cediranib in combination with dasatinib in docetaxel resistant, castration resistant prostate cancer patients.

BACKGROUND: Activation of the vascular endothelial growth factor receptor (VEGFR) and the oncogenic Src pathway has been implicated in the development of castration-resistant prostate cancer (CRPC) in preclinical models. Cediranib and dasatinib are multi-kinase inhibitors targeting VEGFR and Src respectively. Phase II studies of cediranib and dasatinib in CRPC have shown single agent activity. METHODS: Docetaxel-pretreated CRPC patients were randomized to arm A: cediranib alone (20 mg/day) versus arm B: cediranib (20 mg/day) plus dasatinib (100 mg/day) given orally on 4-week cycles. Primary endpoint was 12-week progression-free survival (PFS) as per the Prostate Cancer Clinical Trials Working Group (PCWG2). Patient reported outcomes were evaluated using Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Present Pain Intensity (PPI) scales. Correlative studies of bone turnover markers (BTM), including bone alkaline phosphate (BAP) and serum beta-C telopeptide (B-CTx) were serially assayed. Results A total of 22 patients, 11 per arm, were enrolled. Baseline demographics were similar in both arms. Median number of cycles =4 in arm A (range 1-12) and 2 in arm B (range 1-9). Twelve-week PFS was 73 % in arm A versus 18 % in arm B (p = 0.03). Median PFS in months (arm A versus B) was: 5.2 versus 2.6 (95 % CI: 1.9-6.5 versus 1.4-not reached). Most common grade 3 toxicities were hypertension, anemia and thrombocytopenia in arm A and hypertension, diarrhea and fatigue in arm B. One treatment-related death (retroperitoneal hemorrhage) was seen in arm A. FACT-P and PPI scores did not significantly change in either arm. No correlation between BTM and PFS was seen in either arm. CONCLUSIONS: Although limited by small numbers, this randomized study showed that the combination of VEGFR and Src targeted therapy did not result in improved efficacy and may be associated with a worse outcome than VEGFR targeted therapy alone in patients with CRPC. ClinicalTrials.gov number: NCT01260688.

Towards identifying gaps in employment integration of people living with vision impairment: A scoping review.

Background: The high rate of unemployment among individuals with vision impairment remains a pressing issue, even with the implementation of disability laws and coordinated effort to foster inclusive workplace. Employment integration challenges persist for people with vision impairment due to inaccessible job markets and workplaces. Objective: To create new knowledge from previous studies related to employment among people with vision impairment and to understand what has been explored and identify the gaps in employment integration. Method: A comprehensive search of six databases was conducted utilizing both index terms and keywords. The title and abstract of identified studies were screened, followed by a full-text screening using pre-set criteria. Only available peer-reviewed studies with a focus on employment and vision impairment were included, irrespective of location and publication year. Result: Of 2264 studies screened, only 43 studies were eligible for review and data extraction. Using thematic analysis, 8 key themes emerged: social support, disability rights and service systems, transition strategies and challenges, career, employment integration, employment environment, adaptive potential, and employment sustainability. These studies considered the perspectives of people living with vision impairment, rehabilitation practice, and employers. Identified gaps include transition strategies, workplace participation, the perception of colleagues, and work evolution. Conclusion: The primary focus of studies was on the individual factors that impact workplace integration; work environment impact was not explored in depth. The need to examine the readiness of the work environment is also importance because environmental factors can be modified according to the functional needs of people with vision impairment.

Visual impairment, employment status, and reduction in income: the Canadian Longitudinal Study on Aging.

OBJECTIVE: To examine the employment status of those with and without visual impairment and eye disease and to examine the association between visual impairment and eye disease and a reduction in income over a 3-year period. DESIGN: Population-based prospective cohort study. PARTICIPANTS: A total of 12,174 nonretired participants aged 45-64 years old in the Canadian Longitudinal Study on Aging. METHODS: Visual impairment was defined if binocular presenting or pinhole-corrected monocular visual acuity in the better eye was worse than 20/40 at baseline. Self-reported diagnoses of age-related macular degeneration (AMD) and glaucoma were collected. Employment status (employed, not employed due to sickness or disability, or unemployed) was based on questions on labour force participation. Income reduction was defined as household income <$50,000 per year at follow-up when household income was ≥$50,000 at baseline. Multinomial and logistic regressions were used to adjust for demographic and health variables. RESULTS: Visual impairment using binocular presenting visual acuity (odds ratio [OR] = 2.09; 95% CI, 1.21-3.62) and pinhole-corrected visual acuity (OR = 2.99; 95% CI, 1.54-5.83) were associated with a higher odds of not being employed due to sickness or disability after adjustment. AMD (OR = 1.82; 95% CI, 1.11-3.01) and glaucoma (OR = 2.05; 95% CI, 1.28-3.28) at baseline were both associated with reductions in income over a 3-year period after adjustment. CONCLUSION: Individuals with visual impairment experienced lower employment, and those with AMD or glaucoma were more likely to have their incomes decline over 3 years. Policies to improve workplace participation by those with vision loss are needed.

New sources of drugs for hematologic malignancies.

Advancing novel therapeutic agents for the treatment of malignancy into the marketplace is an increasingly costly and lengthy process. As such, new strategies for drug discovery are needed. Drug repurposing represents an opportunity to rapidly advance new therapeutic strategies into clinical trials at a relatively low cost. Known on-patent or off-patent drugs with unrecognized anticancer activity can be rapidly advanced into clinical testing for this new indication by leveraging their known pharmacology, pharmacokinetics, and toxicology. Using this approach, academic groups can participate in the drug discovery field and smaller biotechnology companies can "de-risk" early-stage drug discovery projects. Here, several scientific approaches used to identify drug repurposing opportunities are highlighted, with a focus on hematologic malignancies. In addition, a discussion of the regulatory issues that are unique to drug repurposing and how they impact developing old drugs for new indications is included. Finally, the mechanisms to enhance drug repurposing through increased collaborations between academia, industry, and nonprofit charitable organizations are discussed.

Hearing disability and employment: a population-based analysis using the 2017 Canadian survey on disability.

Purpose: The objectives of this study were to determine the effects of hearing disability on employment rates; examine how various factors are associated with employment; and identify workplace accommodations available to persons with hearing disabilities in Canada.Material and methods: A population-based analysis was done using the data collected through the 2017 Canadian Survey on Disability (CSD), representing 6 million (n = 6 246 640) Canadians. A subset of the complete dataset was created focusing on individuals with a hearing disability (n = 1 334 520). Weighted descriptive and multivariate logistic regression analyses were performed.Results: In 2017, the employment rates for working-age adults with a hearing disability were 55%. Excellent general health status (OR: 3.37; 95% CI: 2.29-4.96) and daily use of the internet (OR: 2.70; 95% CI: 1.78-4.10) had the highest positive effect on the employment rates. The top three needed but least available accommodations were communication aids (16%), technical aids (19%), and accessible parking/elevator (21%).Conclusion: Employment rates for persons with a hearing disability are lower than the general population in Canada. Employment outcomes are closely associated with one's general health and digital skills. Lack of certain workplace accommodations may disadvantage individuals with a hearing disability in their employment.Implications for RehabilitationPeople with severe hearing disabilities and those with additional disabilities may need additional and more rigorous services and supports to achieve competitive employment.It is important for the government to improve efforts toward inclusive education and develop strategies that promote digital literacy for job seekers with hearing disabilities.Officials concerned with implementing employment equity policies in Canada should focus on finding strategies that enable employees to have supportive conversations with their employers regarding disability disclosure and obtaining required accommodations.

Considerations when asking about "disability" in disability inclusive research.

PURPOSE: There are several ways to include "disability" in research studies, which can be confusing or overwhelming for researchers, community members, and students. The aim of this paper is to share conceptualizations of disability and how to ask about "disability" in research studies. The paper provides a general introduction and brief analysis of the methodological approaches which can be used. METHODS: We used reviews of the literature and extensive discussions to identify key articles, books, websites, and reports that provide guidance and examples of asking about disability in research. RESULTS: Four primary approaches to asking study participants about disability were identified. For each of these, we provide background information, key points about the ways to use the approach including tools that have been developed, and example studies. A comparison table provides a high-level overview of similarities and differences in approaches. Other approaches and tools were also identified and are briefly described. CONCLUSION: Researchers involved in disability and rehabilitation research should be aware that there is not one best or singular way to ask about disability when conducting research. The approach or approaches chosen for a particular study need to match the purpose of the study. It is important that researchers take time to carefully consider their options and choose the best fit for their study.

There are several different ways to ask about disability and functioning when conducting research that aims to include a disability component or focus.Researchers need to carefully select the best option(s) for their study.Whenever possible, researchers should use more than one approach and should allow for more than one type of disability or impairment to be selected.Researchers often require training to understand how to include disability in research.Allow adequate time and resources for training research team members so that the tools are implemented correctly.

An international consensus on effective, inclusive, and career-spanning short-format training in the life sciences and beyond.

Science, technology, engineering, mathematics, and medicine (STEMM) fields change rapidly and are increasingly interdisciplinary. Commonly, STEMM practitioners use short-format training (SFT) such as workshops and short courses for upskilling and reskilling, but unaddressed challenges limit SFT's effectiveness and inclusiveness. Education researchers, students in SFT courses, and organizations have called for research and strategies that can strengthen SFT in terms of effectiveness, inclusiveness, and accessibility across multiple dimensions. This paper describes the project that resulted in a consensus set of 14 actionable recommendations to systematically strengthen SFT. A diverse international group of 30 experts in education, accessibility, and life sciences came together from 10 countries to develop recommendations that can help strengthen SFT globally. Participants, including representation from some of the largest life science training programs globally, assembled findings in the educational sciences and encompassed the experiences of several of the largest life science SFT programs. The 14 recommendations were derived through a Delphi method, where consensus was achieved in real time as the group completed a series of meetings and tasks designed to elicit specific recommendations. Recommendations cover the breadth of SFT contexts and stakeholder groups and include actions for instructors (e.g., make equity and inclusion an ethical obligation), programs (e.g., centralize infrastructure for assessment and evaluation), as well as organizations and funders (e.g., professionalize training SFT instructors; deploy SFT to counter inequity). Recommendations are aligned with a purpose-built framework-"The Bicycle Principles"-that prioritizes evidenced-based teaching, inclusiveness, and equity, as well as the ability to scale, share, and sustain SFT. We also describe how the Bicycle Principles and recommendations are consistent with educational change theories and can overcome systemic barriers to delivering consistently effective, inclusive, and career-spanning SFT.

The antihelmintic flubendazole inhibits microtubule function through a mechanism distinct from Vinca alkaloids and displays preclinical activity in leukemia and myeloma.

On-patent and off-patent drugs with previously unrecognized anticancer activity could be rapidly repurposed for this new indication given their prior toxicity testing. To identify such compounds, we conducted chemical screens and identified the antihelmintic flubendazole. Flubendazole induced cell death in leukemia and myeloma cell lines and primary patient samples at nanomolar concentrations. Moreover, it delayed tumor growth in leukemia and myeloma xenografts without evidence of toxicity. Mechanistically, flubendazole inhibited tubulin polymerization by binding tubulin at a site distinct from vinblastine. In addition, cells resistant to vinblastine because of overexpression of P-glycoprotein remained fully sensitive to flubendazole, indicating that flubendazole can overcome some forms of vinblastine resistance. Given the different mechanisms of action, we evaluated the combination of flubendazole and vinblastine in vitro and in vivo. Flubendazole synergized with vinblastine to reduce the viability of OCI-AML2 cells. In addition, combinations of flubendazole with vinblastine or vincristine in a leukemia xenograft model delayed tumor growth more than either drug alone. Therefore, flubendazole is a novel microtubule inhibitor that displays preclinical activity in leukemia and myeloma.

The antiparasitic agent ivermectin induces chloride-dependent membrane hyperpolarization and cell death in leukemia cells.

To identify known drugs with previously unrecognized anticancer activity, we compiled and screened a library of such compounds to identify agents cytotoxic to leukemia cells. From these screens, we identified ivermectin, a derivative of avermectin B1 that is licensed for the treatment of the parasitic infections, strongyloidiasis and onchocerciasis, but is also effective against other worm infestations. As a potential antileukemic agent, ivermectin induced cell death at low micromolar concentrations in acute myeloid leukemia cell lines and primary patient samples preferentially over normal hematopoietic cells. Ivermectin also delayed tumor growth in 3 independent mouse models of leukemia at concentrations that appear pharmacologically achievable. As an antiparasitic, ivermectin binds and activates chloride ion channels in nematodes, so we tested the effects of ivermectin on chloride flux in leukemia cells. Ivermectin increased intracellular chloride ion concentrations and cell size in leukemia cells. Chloride influx was accompanied by plasma membrane hyperpolarization, but did not change mitochondrial membrane potential. Ivermectin also increased reactive oxygen species generation that was functionally important for ivermectin-induced cell death. Finally, ivermectin synergized with cytarabine and daunorubicin that also increase reactive oxygen species production. Thus, given its known toxicology and pharmacology, ivermectin could be rapidly advanced into clinical trial for leukemia.

Learning to see after early and extended blindness: A scoping review.

Purpose: If an individual has been blind since birth due to a treatable eye condition, ocular treatment is urgent. Even a brief period of visual deprivation can alter the development of the visual system. The goal of our structured scoping review was to understand how we might better support children with delayed access to ocular treatment for blinding conditions. Method: We searched MEDLINE, Embase and Global Health for peer-reviewed publications that described the impact of early (within the first year) and extended (lasting at least 2 years) bilateral visual deprivation. Results: Of 551 reports independently screened by two authors, 42 studies met our inclusion criteria. Synthesizing extracted data revealed several trends. The data suggests persistent deficits in visual acuity, contrast sensitivity, global motion, and visual-motor integration, and suspected concerns for understanding complex objects and faces. There is evidence for resilience in color perception, understanding of simple shapes, discriminating between a face and non-face, and the perception of biological motion. There is currently insufficient data about specific (re)habilitation strategies to update low vision services, but there are several insights to guide future research in this domain. Conclusion: This summary will help guide the research and services provision to help children learn to see after early and extended blindness.

Design, synthesis, and in vitro characterization of novel hybrid peptidomimetic inhibitors of STAT3 protein.

Aberrant activation of oncogenic signal transducer and activator of transcription 3 (STAT3) protein signaling pathways has been extensively implicated in human cancers. Given STAT3's prominent dysregulatory role in malignant transformation and tumorigenesis, there has been a significant effort to discover STAT3-specific inhibitors as chemical probes for defining the aberrant STAT3-mediated molecular events that support the malignant phenotype. To identify novel, STAT3-selective inhibitors suitable for interrogating STAT3 signaling in tumor cells, we explored the design of hybrid molecules by conjugating a known STAT3 inhibitory peptidomimetic, ISS610 to the high-affinity STAT3-binding peptide motif derived from the ILR/gp-130. Several hybrid molecules were examined in in vitro biophysical and biochemical studies for inhibitory potency against STAT3. Lead inhibitor 14aa was shown to strongly bind to STAT3 (K(D)=900 nM), disrupt STAT3:phosphopeptide complexes (K(i)=5 µM) and suppress STAT3 activity in in vitro DNA binding activity/electrophoretic mobility shift assay (EMSA). Moreover, lead STAT3 inhibitor 14aa induced a time-dependent inhibition of constitutive STAT3 activation in v-Src transformed mouse fibroblasts (NIH3T3/v-Src), with 80% suppression of constitutively-active STAT3 at 6h following treatment of NIH3T3/v-Src. However, STAT3 activity recovered at 24h after treatment of cells, suggesting potential degradation of the compound. Results further showed a suppression of aberrant STAT3 activity in NIH3T3/v-Src by the treatment with compound 14aa-OH, which is the non-pTyr version of compound 14aa. The effect of compounds 14aa and 14aa-OH are accompanied by a moderate loss of cell viability.

Employment outcomes and experiences of people with seeing disability in Canada: An analysis of the Canadian Survey on Disability 2017.

BACKGROUND: Many individuals with disabilities face barriers to meaningful employment. Legislation has been put in place to ensure employment equity for individuals with disabilities in Canada. However, little is known about the employment profile and experiences of people with seeing disabilities. OBJECTIVES: The objectives of our research study were to explore the employment rates of people with seeing disabilities in Canada, the factors associated with being employed, and supports and barriers that affect their work participation. METHODS: We used the nationally representative data from the Canadian Survey on Disability (CSD) 2017, collected by Statistics Canada. The CSD is a national cross-sectional survey of Canadians 15 years of age and above who face a functional limitation due to a health-related condition, representing more than 6 million (n = 6,246,640) Canadians. Our analyses focused on people who reported having a seeing disability. A subset of the complete dataset was created, focusing on individuals with a seeing disability. Weighted descriptive analyses were performed using SPSS. Multivariate logistic regression analyses were conducted for individuals between 25-64 years of age to identify predictors of employment. RESULTS: Out of the estimated 892,220 working-age adults (25-64 years) with a seeing disability who were represented by the survey, 54% were employed, 6% were unemployed and 40% were not in the labour force. Early onset of seeing disability (OR: 1.33; 95% CI: 1.32-1.35), less severe seeing disability (OR: 1.51; 95% CI: 1.49-1.53), education above high school (OR: 2.00; 95% CI: 1.97-2.02) and daily use of the internet (OR: 2.46; 95% CI: 2.41-2.51) were positively related with employment. The top three employment accommodations that were needed and were made available included: modified work hours (45%); work from home (38.5%) and a modified workstation (37%). The top three needed but least available accommodations were technical aids (14%), communication aids (22%) and a computer with specialized software or adaptation (27%). Overall, 26% reported that an accommodation was required but was not made available by the employer. While 75% of individuals with a seeing disability were out of the labour force due to their condition, the remaining identified barriers that prevented them from working which included (top 3): (i) too few jobs available (20%); (ii) inadequate training/experience (19%), (iii) past attempts at finding employment were unsuccessful (19%). CONCLUSION: Adults with seeing disability in Canada experience lower labour force participation than the general population. Rigorous programs are required to assist them with the job search, job retraining and workplace accommodations. It is important for governments to improve efforts towards inclusive education and develop strategies that promote digital literacy of employees and job seekers with visual impairments. Although accessibility legislations have been put in place, programs should be established that provide accessibility solutions for various employers, enabling them to hire individuals with different abilities.

Online Self-Determination Toolkit for Youth With Disabilities: Protocol for a Mixed Methods Evaluation Study.

BACKGROUND: Youth with disabilities encounter many challenges during their transition to adulthood including finding employment. Jobs are often inaccessible, and youth often face a lack of support, discriminatory attitudes, and sometimes low self-confidence. Therefore, it is critical to help youth enhance their self-determination skills to advocate for their needs in the workplace. OBJECTIVE: The aim of this paper is to describe how an online toolkit aimed to improve self-determination in advocating for needs, including disability disclosure and accommodation requests to employers, was co-created with youth with disabilities. METHODS: We will use a mixed method design in which qualitative data (ie, focus groups and mentored discussion forum) are collected to understand the contextual factors during the intervention that could affect outcomes or explain results through the pre-post questionnaires. Fifty youths with disabilities aged 15 to 24 years will be recruited. RESULTS: Data collection is in progress. Planned analyses include focus groups and pre-post surveys to determine the impact of the intervention on self-determination. A qualitative content analysis of the focus groups and all open-ended survey questions will be conducted to understand the impact of the toolkit. CONCLUSIONS: Our online toolkit includes evidence-informed content that was co-created with youth who have a disability. It has potential for educational and vocational programming for youth with disabilities. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/20463.

Programmed cell death 4 loss increases tumor cell invasion and is regulated by miR-21 in oral squamous cell carcinoma.

BACKGROUND: The tumor suppressor Programmed Cell Death 4 (PDCD4) has been found to be under-expressed in several cancers and associated with disease progression and metastasis. There are no current studies characterizing PDCD4 expression and its clinical relevance in Oral Squamous Cell Carcinoma (OSCC). Since nodal metastasis is a major prognostic factor in OSCC, we focused on determining whether PDCD4 under-expression was associated with patient nodal status and had functional relevance in OSCC invasion. We also examined PDCD4 regulation by microRNA 21 (miR-21) in OSCC. RESULTS: PDCD4 mRNA expression levels were assessed in 50 OSCCs and 25 normal oral tissues. PDCD4 was under-expressed in 43/50 (86%) OSCCs, with significantly reduced mRNA levels in patients with nodal metastasis (p = 0.0027), and marginally associated with T3-T4 tumor stage (p = 0.054). PDCD4 protein expression was assessed, by immunohistochemistry (IHC), in 28/50 OSCCs and adjacent normal tissues; PDCD4 protein was absent/under-expressed in 25/28 (89%) OSCCs, and marginally associated with nodal metastasis (p = 0.059). A matrigel invasion assay showed that PDCD4 expression suppressed invasion, and siRNA-mediated PDCD4 loss was associated with increased invasive potential of oral carcinoma cells. Furthermore, we showed that miR-21 levels were increased in PDCD4-negative tumors, and that PDCD4 expression may be down-regulated in OSCC by direct binding of miR-21 to the 3'UTR PDCD4 mRNA. CONCLUSIONS: Our data show an association between the loss of PDCD4 expression, tumorigenesis and invasion in OSCC, and also identify a mechanism of PDCD4 down-regulation by microRNA-21 in oral carcinoma. PDCD4 association with nodal metastasis and invasion suggests that PDCD4 may be a clinically relevant biomarker with prognostic value in OSCC.

Assessing the Diagnostic Yield of Targeted Next-Generation Sequencing for Melanoma and Gastrointestinal Tumors.

A common rationale in molecular diagnostic laboratories is that implementation of next-generation sequencing (NGS) enables simultaneous multigene testing, allowing increased information benefit compared with non-NGS assays. However, minimal published data exist to support this justification. The current study compared clinical diagnostic yield of TruSight Tumor 26 Sequencing Panel (TST26) in melanoma, colorectal (CRC), and gastrointestinal stromal (GIST) tumors with non-NGS assays. A total of 1041 formalin-fixed, paraffin-embedded tumors, of melanoma, CRC, and GIST, were profiled. NGS results were compared with non-NGS single-gene or single-variant assays with respect to variant output and diagnostic yield. A total of 79% melanoma and 94% CRC tumors were variant positive by panel testing. TST26 panel improved serine/threonine-protein kinase B-raf (BRAF) variant detection in melanoma compared with single-variant BRAF Val600Glu/Lys (V600E/K) routine tests by 24% and detected variants in genes other than BRAF, NRAS, and KIT, which could impact patient management in 20% additional cases. NGS enhanced diagnostic yield in CRC by 36% when compared with routine single-gene assays. In contrast, no added benefit of NGS-based testing for GIST tumors was observed. TST26 panel either missed or inaccurately called complex insertion/deletion variants in KIT exon 11, which were accurately identified by non-NGS methods. Findings of this study demonstrate the differential impact of cancer site and variant type on diagnostic test information yield from NGS assays.