Dynamic changes in the endoplasmic reticulum (ER) morphology are central to maintaining cellular homeostasis. Microtubules (MT) facilitate the continuous remodeling of the ER network into sheets and tubules by coordinating with many ER-shaping protein complexes, although how this process is controlled by extracellular signals remains unknown. Here we report that TAK1, a kinase responsive to various growth factors and cytokines including TGF-β and TNF-α, triggers ER tubulation by activating αTAT1, an MT-acetylating enzyme that enhances ER-sliding.
View Article and Find Full Text PDFBackground And Objectives: eNAMPT (extracellular nicotinamide phosphoribosyltransferase), a novel DAMP and TLR4 ligand, is a druggable ARDS therapeutic target with promoter SNPs associated with ARDS severity. This study assesses the previously unknown influence of promoter SNPs on transcription, eNAMPT secretion, and ARDS severity.
Methods And Design: Human lung endothelial cells (ECs) transfected with promoter luciferase reporters harboring SNPs G-1535A, A-1001 C, and C-948A, were exposed to LPS or LPS/18% cyclic stretch (CS) and promoter activity, NAMPT protein expression, and secretion assessed.
Dynamic changes in the endoplasmic reticulum (ER) morphology are central to maintaining cellular homeostasis. Microtubules (MT) facilitate the continuous remodeling of the ER network into sheets and tubules by coordinating with many ER-shaping protein complexes, although how this process is controlled by extracellular signals remains unknown. Here we report that TAK1, a kinase responsive to numerous growth factors and cytokines including TGF-β and TNF-α, triggers ER tubulation by activating αTAT1, an MT-acetylating enzyme that enhances ER-sliding.
View Article and Find Full Text PDFBackground: The United States is becoming increasingly diverse, but few molecular studies have assessed the progression of clear cell renal cell carcinoma (ccRCC) in diverse patient populations. This study examined ccRCC molecular variations in non-Hispanic White (NHW) and Hispanic patients and their effect on the association of gene expression with high-grade (Grade 3 or 4) ccRCC and overall mortality.
Methods: A total of 156 patients were included in VHL sequencing and/or TempO-Seq analysis.
The establishment and maintenance of different cellular compartments in tissues is a universal requirement across all metazoans. Maintaining the correct ratio of cell types in time and space allows tissues to form patterned compartments and perform complex functions. Patterning is especially evident in the human colon, where tissue homeostasis is maintained by stem cells in crypt structures that balance proliferation and differentiation.
View Article and Find Full Text PDFBLM is sumoylated in response to replication stress. We have studied the role of BLM sumoylation in physiologically normal and replication-stressed conditions by expressing in BLM-deficient cells a BLM with SUMO acceptor-site mutations, which we refer to as SUMO-mutant BLM cells. SUMO-mutant BLM cells exhibited multiple defects in both stressed and unstressed DNA replication conditions, including, in hydroxyurea-treated cells, reduced fork restart and increased fork collapse and, in untreated cells, slower fork velocity and increased fork instability as assayed by track-length asymmetry.
View Article and Find Full Text PDFDefective angiogenesis underlies over 50 malignant, ischemic and inflammatory disorders yet long-term therapeutic applications inevitably fail, thus highlighting the need for greater understanding of the vast crosstalk and compensatory mechanisms. Based on proteomic profiling of angiogenic endothelial components, here we report β-spectrin, a non-erythrocytic cytoskeletal protein, as a critical regulator of sprouting angiogenesis. Early loss of endothelial-specific β-spectrin promotes embryonic lethality in mice due to hypervascularization and hemorrhagic defects whereas neonatal depletion yields higher vascular density and tip cell populations in developing retina.
View Article and Find Full Text PDFBackground: Mismatch repair (MMR) deficiency is the hallmark of tumours from Lynch syndrome (LS), sporadic MLH1 hypermethylated and Lynch-like syndrome (LLS), but there is a lack of understanding of the variability in their mutational profiles based on clinical phenotypes. The aim of this study was to perform a molecular characterisation to identify novel features that can impact tumour behaviour and clinical management.
Methods: We tested 105 MMR-deficient colorectal cancer tumours (25 LS, 35 LLS and 45 sporadic) for global exome microsatellite instability, cancer mutational signatures, mutational spectrum and neoepitope load.
Oxylipins derived from arachidonic acid (ARA) have been implicated in the development of colorectal adenomas and colorectal cancer. The primary purpose of this work was to determine the relationship between plasma levels of oxylipins and colorectal adenoma characteristics at study entry, as well as with the development of a new adenoma during follow-up within a Phase III adenoma prevention clinical trial with selenium (Sel). Secondarily, we sought to determine whether the selenium intervention influenced plasma oxylipin levels.
View Article and Find Full Text PDFBackground: Selenium (Se) is a trace element that has been linked to many health conditions. Genome-wide association studies (GWAS) have identified variants for blood and toenail Se levels, but no GWAS has been conducted to date on responses to Se supplementation.
Objectives: A GWAS was performed to identify the single nucleotide polymorphisms (SNPs) associated with changes in Se concentrations after 1 year of supplementation.
Genes Chromosomes Cancer
August 2020
Despite improvements over the past 20 years, African Americans continue to have the highest incidence and mortality rates of colorectal cancer (CRC) in the United States. While previous studies have found that copy number variations (CNVs) occur at similar frequency in African American and White CRCs, copy-neutral loss of heterozygosity (cnLOH) has not been investigated. In the present study, we used publicly available data from The Cancer Genome Atlas (TCGA) as well as data from an African American CRC cohort, the Chicago Colorectal Cancer Consortium (CCCC), to compare frequencies of CNVs and cnLOH events in CRCs in the two racial groups.
View Article and Find Full Text PDFFanconi anaemia (FA), ataxia telangiectasia (A-T), Nijmegen breakage syndrome (NBS) and Bloom syndrome (BS) are clinically distinct, chromosome instability (or breakage) disorders. Each disorder has its own pattern of chromosomal damage, with cells from these patients being hypersensitive to particular genotoxic drugs, indicating that the underlying defect in each case is likely to be different. In addition, each syndrome shows a predisposition to cancer.
View Article and Find Full Text PDFThe double-strand break (DSB) is the most cytotoxic type of DNA damage and measurement of DSBs in cells is essential to understand their induction and repair. Pulsed-field gel electrophoresis (PFGE) allows for quantitative measurement of DSBs in a cell population generated by DNA damaging agents. PFGE has the capacity to separate DNA molecules from several hundred base pairs to over six million base pairs.
View Article and Find Full Text PDFMany colorectal cancers (CRCs) that exhibit microsatellite instability (MSI) are not explained by MLH1 promoter methylation or germline mutations in mismatch repair (MMR) genes, which cause Lynch syndrome (LS). Instead, these Lynch-like syndrome (LLS) patients have somatic mutations in MMR genes. However, many of these patients are young and have relatives with cancer, suggesting a hereditary entity.
View Article and Find Full Text PDFFirefighters are exposed to carcinogens and have elevated cancer rates. We hypothesized that occupational exposures in firefighters would lead to DNA methylation changes associated with activation of cancer pathways and increased cancer risk. To address this hypothesis, we collected peripheral blood samples from 45 incumbent and 41 new recruit non-smoking male firefighters and analyzed the samples for DNA methylation using an Illumina Methylation EPIC 850k chip.
View Article and Find Full Text PDFBMJ Open Diabetes Res Care
April 2020
Objective: While controversial, observational and randomized clinical trial data implicate the micronutrient selenium (Se) in the development of type 2 diabetes (T2D). The aim of this study was to test the hypothesis that Se supplementation adversely affects pancreatic β-cell function and insulin sensitivity.
Research Design And Methods: In a subset of 400 individuals participating in a randomized, placebo-controlled trial of Se at 200 µg/day for colorectal adenomatous polyps, fasting plasma glucose and insulin were measured before randomization and within 6 months of completing intervention.
NSMCE2 is an E3 SUMO ligase and a subunit of the SMC5/6 complex that associates with the replication fork and protects against genomic instability. Here, we study the fate of collapsed replication forks generated by prolonged hydroxyurea treatment in human NSMCE2-deficient cells. Double strand breaks accumulate during rescue by converging forks in normal cells but not in NSMCE2-deficient cells.
View Article and Find Full Text PDFClear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of kidney cancer, yet molecular biomarkers have not been used for the prognosis of ccRCC to aide clinical decision making. This study aimed to identify genes associated with ccRCC aggressiveness and overall survival (OS). Samples of ccRCC tumor tissue were obtained from 33 patients who underwent nephrectomy.
View Article and Find Full Text PDFAfrican Americans (AAs) have higher incidence and mortality rates of colorectal cancer (CRC) compared with other US populations. They present with more right-sided, microsatellite stable disease and are diagnosed at earlier ages compared with non-Hispanic Whites (NHWs). To gain insight into these trends, we conducted exome sequencing (n = 45), copy number (n = 33) and methylation analysis (n = 11) of microsatellite stable AA CRCs.
View Article and Find Full Text PDFIntroduction: Pseudogenes are paralogues of functional genes historically viewed as defunct due to either the lack of regulatory elements or the presence of frameshift mutations. Recent evidence, however, suggests that pseudogenes may regulate gene expression, although the functional role of pseudogenes remains largely unknown. We previously reported that MYLKP1, the pseudogene of MYLK that encodes myosin light chain kinase (MLCK), is highly expressed in lung and colon cancer cell lines and tissues but not in normal lung or colon.
View Article and Find Full Text PDFBloom Syndrome (BSyn) is an autosomal recessive disorder that causes growth deficiency, endocrine abnormalities, photosensitive skin rash, immune abnormalities, and predisposition to early-onset cancer. The available treatments for BSyn are symptomatic, and early identification of complications has the potential to improve outcomes. To accomplish this, standardized recommendations for health supervision are needed for early diagnosis and treatment.
View Article and Find Full Text PDFBackground: Screening in the average risk population for colorectal cancer (CRC) is expected to reduce the incidence of distant (i.e., metastatic) CRCs at least as much as less advanced CRCs.
View Article and Find Full Text PDFCancer disparities in Native Americans (NAs) and Hispanic Americans (HAs) vary significantly in terms of cancer incidence and mortality rates across geographic regions. This review reports that kidney and renal pelvis cancers are unevenly affecting HAs and NAs compared to European Americans of non-Hispanic origin, and that currently there is significant need for improved data and reporting to be able to advance toward genomic-based precision medicine for the assessment of such cancers in these medically underserved populations. More specifically, in states along the US-Mexico border, HAs and NAs have higher kidney cancer incidence rates as well as a higher prevalence of kidney cancer risk factors, including obesity and chronic kidney disease.
View Article and Find Full Text PDFAfrican Americans have the highest incidence and mortality rates of colorectal cancer (CRC) of any ethnic group in the United States. Although some of these disparities can be explained by differences in access to care, cancer screening, and other socioeconomic factors, disparities remain after adjustment for these factors. Consequently, an examination of recent advances in the understanding of ethnicity-specific factors, including genetic and environmental factors relating to risk of CRC, the biology of CRC progression, and the changes in screening and mortality, is important for evaluating our progress toward eliminating the disparities.
View Article and Find Full Text PDFBloom's syndrome is an autosomal recessive disorder characterized by prenatal and postnatal growth deficiency, photosensitive skin changes, immune deficiency, insulin resistance, and a greatly increased risk of early onset of cancer and for the development of multiple cancers. Loss-of-function mutations of , which codes for a RecQ helicase, cause Bloom's syndrome. The absence of a functional BLM protein causes chromosome instability, excessive homologous recombination, and a greatly increased number of sister chromatid exchanges that are pathognomonic of the syndrome.
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