Publications by authors named "Bernard Levin"

Cancer cell proliferation requires precise control of E2F1 activity; excess activity promotes apoptosis. Here, we developed cell-permeable and bioavailable macrocycles that selectively kill small cell lung cancer (SCLC) cells with inherent high E2F1 activity by blocking RxL-mediated interactions of cyclin A and cyclin B with select substrates. Genome-wide CRISPR/Cas9 knockout and random mutagenesis screens found that cyclin A/B RxL macrocyclic inhibitors (cyclin A/Bi) induced apoptosis paradoxically by cyclin B- and Cdk2-dependent spindle assembly checkpoint activation (SAC).

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Article Synopsis
  • Scientists are finding new ways to test for colorectal cancer that are easier and less invasive than traditional methods.
  • A group of experts updated the rules for how to evaluate these new tests to make sure they're effective.
  • The new tests should be compared to the existing reliable tests and go through several phases of research to ensure they're safe and useful in real-world situations.
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Individuals with colorectal cancer (CRC) have a tendency to intestinal bleeding which may result in mild to severe iron deficiency anemia, but for many colon cancer patients hematological abnormalities are subtle. The fecal occult blood test (FOBT) is used as a pre-screening test whereby those with a positive FOBT are referred to colonscopy. We sought to determine if information contained in the complete blood count (CBC) report coud be processed automatically and used to predict the presence of occult colorectal cancer (CRC) in the setting of a large health services plan.

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Multitarget stool DNA (mt-sDNA) testing was approved for average risk colorectal cancer (CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program (2014). The United States Preventive Services Task Force (USPSTF) October 2015 draft recommendation for CRC screening included mt-sDNA as an "alternative" screening test that "may be useful in select clinical circumstances", despite its very high sensitivity for early stage CRC. The evidence supporting mt-sDNA for routine screening use is robust.

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Objective: The use of risk prediction models grows as electronic medical records become widely available. Here, we develop and validate a model to identify individuals at increased risk for colorectal cancer (CRC) by analyzing blood counts, age, and sex, then determine the model's value when used to supplement conventional screening.

Materials And Methods: Primary care data were collected from a cohort of 606 403 Israelis (of whom 3135 were diagnosed with CRC) and a case control UK dataset of 5061 CRC cases and 25 613 controls.

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Objectives: The US Preventive Services Task Force (USPSTF) released draft recommendations regarding colorectal cancer (CRC) screening in October 2015. Despite evidence that annual fecal blood testing test use is uncommon in screen eligible adults, with only 10.4% reporting the use of such a test in 2012, and features poor adherence over time, the USPSTF recommended only 3 noninvasive screening strategy options, all including annual fecal occult blood testing: 1) annual fecal immunochemical test (FIT) alone; 2) annual FIT in combination with flexible sigmoidoscopy every 10 years; and 3) annual high-sensitivity fecal occult blood test (hsFOBT).

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Background: New screening tests for colorectal cancer continue to emerge, but the evidence needed to justify their adoption in screening programs remains uncertain.

Methods: A review of the literature and a consensus approach by experts was undertaken to provide practical guidance on how to compare new screening tests with proven screening tests.

Results: Findings and recommendations from the review included the following: Adoption of a new screening test requires evidence of effectiveness relative to a proven comparator test.

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The human immunodeficiency virus (HIV)-specific cytotoxic T lymphocyte (CTL) response is critical in controlling HIV infection. Since the immune response does not eliminate HIV, it would be beneficial to develop ways to enhance the HIV-specific CTL response to allow long-term viral suppression or clearance. Here, we report the use of a protective chimeric antigen receptor (CAR) in a hematopoietic stem/progenitor cell (HSPC)-based approach to engineer HIV immunity.

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We described earlier a dual-combination anti-HIV type 1 (HIV-1) lentiviral vector (LVsh5/C46) that downregulates CCR5 expression of transduced cells via RNAi and inhibits HIV-1 fusion via cell surface expression of cell membrane-anchored C46 antiviral peptide. This combinatorial approach has two points of inhibition for R5-tropic HIV-1 and is also active against X4-tropic HIV-1. Here, we utilize the humanized bone marrow, liver, thymus (BLT) mouse model to characterize the in vivo efficacy of LVsh5/C46 (Cal-1) vector to engineer cellular resistance to HIV-1 pathogenesis.

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Unlabelled: A unique aspect of human monocytes, compared to monocytes from many other species, is that they express the CD4 molecule. However, the role of the CD4 molecule in human monocyte development and function is not known. We determined that the activation of CD4 via interaction with major histocompatibility complex class II (MHC-II) triggers cytokine expression and the differentiation of human monocytes into functional mature macrophages.

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Purpose: Demographic, behavioral, and environmental factors have been associated with increased risk of colorectal cancer (CRC). We reviewed the published evidence and explored associations between risk factors and CRC incidence.

Methods: We identified 12 established non-screening CRC risk factors and performed a comprehensive review and meta-analyses to quantify each factor's impact on CRC risk.

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Background: Accurate measures of the total polyp burden in familial adenomatous polyposis (FAP) are lacking. Current assessment tools include polyp quantitation in limited-field photographs and qualitative total colorectal polyp burden by video.

Objective: To develop global quantitative tools of the FAP colorectal adenoma burden.

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Small animal models such as mice have been extensively used to study human disease and to develop new therapeutic interventions. Despite the wealth of information gained from these studies, the unique characteristics of mouse immunity as well as the species specificity of viral diseases such as human immunodeficiency virus (HIV) infection led to the development of humanized mouse models. The earlier models involved the use of C.

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The HIV-specific cytotoxic T lymphocyte (CTL) response is a critical component in controlling viral replication in vivo, but ultimately fails in its ability to eradicate the virus. Our intent in these studies is to develop ways to enhance and restore the HIV-specific CTL response to allow long-term viral suppression or viral clearance. In our approach, we sought to genetically manipulate human hematopoietic stem cells (HSCs) such that they differentiate into mature CTL that will kill HIV infected cells.

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Background: Previous gastrointestinal (GI) outcomes of nonsteroidal anti-inflammatory drug (NSAID) trials have focused on upper GI events, although recent evidence suggests NSAID-related lower GI effects are important and clinically relevant.

Objective: We assessed the long-term GI adverse event (AE) profile of celecoxib in a nonarthritis population. The aim of this post hoc analysis was to determine the incidence of serious GI AEs, using a new Clinically Significant Upper and/or Lower GI Events end point.

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Objectives: Subjects in the Prevention of Colorectal Sporadic Adenomatous Polyps (PreSAP) trial (PRESAP/NCT00141193/www.clinicaltrials.gov) were studied to determine efficacy and safety at a year 5 assessment.

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Analysis of abnormally methylated genes is increasingly important in basic research and in the development of cancer biomarkers. We have developed methyl-BEAMing technology to enable absolute quantification of the number of methylated molecules in a sample. Individual DNA fragments are amplified and analyzed either by flow cytometry or next-generation sequencing.

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Background: Over 11% of the US population in 2002 was foreign born. Studies that have examined disparities of cancer screening often focus on racial/ethnicity differences without considering their origins. This study examines the disparities in colorectal cancer (CRC) screening between US- and foreign-born groups and explores factors associated with such disparities.

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This article describes a joint update of guidelines by the American Cancer Society and the U.S. Multi-Society Task Force on Colorectal Cancer delineating evidence-based surveillance recommendations for patients after polypectomy and colorectal cancer resection.

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