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Background: Folate is involved in multiple genetic, epigenetic, and metabolic processes, and inadequate folate intake has been associated with an increased risk of cancer., Objective: We examined whether folate intake is differentially associated with colorectal cancer (CRC) risk according to somatic mutations in genes linked to CRC using targeted sequencing., Design: Participants within 2 large CRC consortia with available information on dietary folate, supplemental folic acid, and total folate intake were included. Colorectal tumor samples from cases were sequenced for the presence of nonsilent mutations in 105 genes and 6 signaling pathways (IGF2/PI3K, MMR, RTK/RAS, TGF-β, WNT, and TP53/ATM). Multinomial logistic regression models were analyzed comparing mutated/nonmutated CRC cases to controls to compute multivariable-adjusted odds ratios (ORs) with 95% confidence interval (CI). Heterogeneity of associations of mutated compared with nonmutated CRC cases was tested in case-only analyses using logistic regression. Analyses were performed separately in hypermutated and nonhypermutated tumors, because they exhibit different clinical behaviors., Results: We included 4339 CRC cases (702 hypermutated tumors, 16.2%) and 11,767 controls. Total folate intake was inversely associated with CRC risk (OR = 0.93; 95% CI: 0.90, 0.96). Among hypermutated tumors, 12 genes (AXIN2, B2M, BCOR, CHD1, DOCK3, FBLN2, MAP3K21, POLD1, RYR1, TET2, UTP20, and ZNF521) showed nominal statistical significance (P < 0.05) for heterogeneity by mutation status, but none remained significant after multiple testing correction. Among these genetic subtypes, the associations between folate variables and CRC were mostly inverse or toward the null, except for tumors mutated for DOCK3 (supplemental folic acid), CHD1 (total folate), and ZNF521 (dietary folate) that showed positive associations. We did not observe differential associations in analyses among nonhypermutated tumors, or according to the signaling pathways., Conclusions: Folate intake was not differentially associated with CRC risk according to mutations in the genes explored. The nominally significant differential mutation effects observed in a few genes warrants further investigation., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Epidemiological and experimental evidence suggests that higher folate intake is associated with decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate's role in CRC., Objectives: Our aim was to perform a genome-wide interaction analysis to identify genetic variants that may modify the association of folate on CRC risk., Methods: We applied traditional case-control logistic regression, joint 3-degree of freedom, and a 2-step weighted hypothesis approach to test the interactions of common variants (allele frequency >1%) across the genome and dietary folate, folic acid supplement use, and total folate in relation to risk of CRC in 30,550 cases and 42,336 controls from 51 studies from 3 genetic consortia (CCFR, CORECT, GECCO)., Results: Inverse associations of dietary, total folate, and folic acid supplement with CRC were found (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.90, 0.96; and 0.91; 95% CI: 0.89, 0.94 per quartile higher intake, and 0.82 (95% CI: 0.78, 0.88) for users compared with nonusers, respectively). Interactions (P-interaction < 5×10 -8 ) of folic acid supplement and variants in the 3p25.2 locus (in the region of Synapsin II [SYN2]/tissue inhibitor of metalloproteinase 4 [TIMP4]) were found using traditional interaction analysis, with variant rs150924902 (located upstream to SYN2) showing the strongest interaction. In stratified analyses by rs150924902 genotypes, folate supplementation was associated with decreased CRC risk among those carrying the TT genotype (OR: 0.82; 95% CI: 0.79, 0.86) but increased CRC risk among those carrying the TA genotype (OR: 1.63; 95% CI: 1.29, 2.05), suggesting a qualitative interaction (P-interaction = 1.4×10 -8 ). No interactions were observed for dietary and total folate., Conclusions: Variation in 3p25.2 locus may modify the association of folate supplement with CRC risk. Experimental studies and studies incorporating other relevant omics data are warranted to validate this finding., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies., (© 2016 by The American Society of Hematology.)

Background: Studies of the role of dietary factors in epithelial ovarian cancer (EOC) development have been limited, and no specific dietary factors have been consistently associated with EOC risk., Objective: We used a nutrient-wide association study approach to systematically test the association between dietary factors and invasive EOC risk while accounting for multiple hypothesis testing by using the false discovery rate and evaluated the findings in an independent cohort., Design: We assessed dietary intake amounts of 28 foods/food groups and 29 nutrients estimated by using dietary questionnaires in the EPIC (European Prospective Investigation into Cancer and Nutrition) study (n = 1095 cases). We selected 4 foods/nutrients that were statistically significantly associated with EOC risk when comparing the extreme quartiles of intake in the EPIC study (false discovery rate = 0.43) and evaluated these factors in the NLCS (Netherlands Cohort Study; n = 383 cases). Cox regression models were used to estimate HRs and 95% CIs., Results: None of the 4 dietary factors that were associated with EOC risk in the EPIC study (cholesterol, polyunsaturated and saturated fat, and bananas) were statistically significantly associated with EOC risk in the NLCS; however, in meta-analysis of the EPIC study and the NLCS, we observed a higher risk of EOC with a high than with a low intake of saturated fat (quartile 4 compared with quartile 1; overall HR: 1.21; 95% CI: 1.04, 1.41)., Conclusion: In the meta-analysis of both studies, there was a higher risk of EOC with a high than with a low intake of saturated fat., (© 2016 American Society for Nutrition.)

There are inconsistent and limited data available to assess the relationship between fat intake and risk of epithelial ovarian cancer (EOC). We examined the consumption of total fat, fat sources and fat subtypes in relation to risk of EOC and its major histologic subtypes in the European Prospective Investigation into Cancer and Nutrition which includes incident invasive (n=1095) and borderline (n=96) EOC. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). In multivariate models, we observed no association with consumption of total fat, animal or plant fat, saturated fat, cholesterol, monounsaturated fat, or fatty fish and risk of invasive EOC. There was, however, an increased risk of invasive EOC in the highest category of intake (Quartile 4 vs. Quartile 1) of polyunsaturated fat (HR=1.22, 95% CI=1.02-1.48, P(trend)=0.02). We did not observe heterogeneity in the risk associations in comparisons of serous and endometrioid histologic subtypes. This study does not support an etiological role for total fat intake in relation to EOC risk; however, based on observations of a positive association between intake of polyunsaturated fat and invasive EOC risk in the current and previous studies, this fat subtype warrants further investigation to determine its potential role in EOC development., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: In 1994, acrylamide (AA) was classified as a probable human carcinogen by the International Agency for Research on Cancer. In 2002, AA was discovered at relatively high concentrations in some starchy, plant-based foods cooked at high temperatures., Patients and Methods: A prospective analysis was conducted to evaluate the association between the dietary intake of AA and ductal adenocarcinoma of the exocrine pancreatic cancer (PC) risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort using Cox regression modeling. EPIC includes >500,000 men and women aged 35-75 at enrollment from 10 European countries. AA intake was estimated for each participant by combining questionnaire-based food consumption data with a harmonized AA database derived from the EU monitoring database of AA levels in foods, and evaluated in quintiles and continuously., Results: After a mean follow-up of 11 years, 865 first incident adenocarcinomas of the exocrine pancreas were observed and included in the present analysis. At baseline, the mean dietary AA intake in EPIC was 26.22 µg/day. No overall association was found between continuous or quintiles of dietary AA intake and PC risk in EPIC (HR:0.95, 95%CI:0.89-1.01 per 10 µg/day). There was no effect measure modification by smoking status, sex, diabetes, alcohol intake or geographic region. However, there was an inverse association (HR: 0.73, 95% CI: 0.61-0.88 per 10 µg/day) between AA intake and PC risk in obese persons as defined using the body mass index (BMI, ≥ 30 kg/m(2)), but not when body fatness was defined using waist and hip circumference or their ratio., Conclusions: Dietary intake of AA was not associated with an increased risk of PC in the EPIC cohort.

The Raf/MEK/extracellular signal-regulated kinase (ERK) pathway participates in many processes altered in development and progression of cancer in human beings such as proliferation, transformation, differentiation, and apoptosis. Kinase suppressor of Ras 1 (KSR1) can interact with various kinases of the Raf/MEK/extracellular signal-regulated kinase pathway to enhance its activation. The role of KSR1 in endometrial carcinogenesis was investigated. cDNA and tissue microarrays demonstrated that expression of KSR1 was up-regulated in endometrial carcinoma. Furthermore, inhibition of KSR1 expression by specific small hairpin RNA resulted in reduction of both proliferation and anchorage-independent cell growth properties of endometrial cancer cells. Because inhibition of apoptosis has a pivotal role in endometrial carcinogenesis, the effects of KSR1 in regulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis were investigated. KSR1 knock-down sensitized resistant endometrial cell lines to both TRAIL- and Fas-induced apoptosis. Sensitization to TRAIL and agonistic anti-Fas antibody was caused by down-regulation of FLIP (FLICE-inhibitory protein). Also investigated was the molecular mechanism by which KSR1 regulates FLIP protein levels. It was demonstrated that KSR1 small hairpin RNA did not affect FLIP transcription or degradation. Rather, FLIP down-regulation was caused by Fas-associated death domain protein-dependent inhibition of FLIP translation triggered after TRAIL stimulation in KSR1-silenced cells. Re-expression of heterologous KSR1 in cells with down-regulated endogenous KSR1 restored FLIP protein levels and TRAIL resistance. In conclusion, KSR1 regulates endometrial sensitivity to TRAIL by regulating FLIP levels., (Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Development of three-dimensional (3D) cultures that mimic in vivo tissue organization has a pivotal role in the investigation of the involvement of cell adhesion and polarity genes in the pathogenesis of epithelial cancers. Here we describe a novel 3D culture model with primary mouse endometrial epithelial cells. In this model, isolated endometrial epithelial cells develop single-lumened, polarized glandular structures resembling those observed in endometrial tissue. Our in vitro 3D culture model of endometrial glands requires the use of serum-free defined medium with only epidermal growth factor and insulin as growth supplements and 3% Matrigel as reconstituted extracellular matrix. Under these culture conditions, glands of epithelial cells displaying typical apicobasal polarity and proper positioning of tight and adherent junctions are formed by hollowing as early as 7 to 8 days in culture. Addition of the phosphatidylinositol 3-kinase inhibitor LY294002 completely inhibits bromodeoxyuridine incorporation and cyclinD1 expression, confirming that in vitro growth of endometrial glands depends on phosphatidylinositol 3-kinase/Akt signaling. To prove that our culture method is a good model to study endometrial carcinogenesis, we knocked down E-cadherin or phosphatase and tensin homolog expression by lentivirus-delivered short hairpin RNAs. Down-regulation of E-cadherin resulted in complete loss of epithelial cell polarity and glandular formation, whereas phosphatase and tensin homolog down-regulation resulted in increased proliferation of glandular epithelial cells. These properties indicate that our 3D culture model is suitable to study the effect of growth factors, drugs, and gene alterations in endometrial carcinogenesis and to study normal endometrial biology/physiology.

Protein kinase CK2 (CK2) is a serine/threonine kinase that participates in important cellular processes. We have recently demonstrated that CK2 plays a role in resistance to TRAIL/Fas-induced apoptosis in endometrial carcinoma (EC) by regulating FLIP. Here, we assessed the immunohistochemical expression of CK2beta in EC and checked its role in cell proliferation and anchorage-independent cell growth. CK2beta immunostaining was assessed in two tissue microarrays, one constructed from paraffin-embedded blocks of 95 ECs and another from 70 samples of normal endometrium. CK2beta expression was correlated with histological type; grade and stage; cell proliferation (Ki-67) and apoptotic index; immunostaining for cyclin D1, PTEN, AKT, beta-catenin, and FLIP. Moreover, the Ishikawa EC cell line was subjected to down-regulation of CK2 by shRNA. CK2beta expression was frequent in EC (nuclear, 100%; cytoplasmic, 87.5%). The staining was more intense in EC than in normal endometrium (P = 0.000), and statistically correlated with AKT, PTEN, beta-catenin, and FLIP. In EC, CK2beta expression correlated with cell proliferation. Knock-down of CK2beta blocked colony formation of EC in soft agar, and also resulted in decreased expression of cyclin D1 and ERK phosphorylation. The results confirm that CK2beta is widely expressed in EC, and suggest a role in cell proliferation and anchorage-independent cell growth.