Development of colorectal cancer (CRC) can occur both via gene mutations in tumor suppressor genes and oncogenes, as well as via epigenetic changes, including DNA methylation. Site-specific methylation in CRC regulates expression of tumor-associated genes. Right-sided colon tumors more frequently have BRAF (p.
View Article and Find Full Text PDFBackground: Cancer-specific hypermethylation of (promoter) CpG islands is common during the tumorigenesis of colon cancer. Although associations between certain genetic aberrations, such as BRAF mutation and microsatellite instability, and the CpG island methylator phenotype (CIMP), have been found, the mechanisms by which these associations are established are still unclear. We studied genome-wide DNA methylation differences between colorectal tumors carrying a BRAF mutation and BRAF wildtype tumors.
View Article and Find Full Text PDFDevelopment of colon cancer is a multistep process that is regulated by intrinsic and extrinsic cellular signals. Extrinsic factors include molecular patterns that are derived from either pathogens (PAMPs) or cellular damage (DAMPs). These molecules can promote tumourigenesis by activation of the innate immune system, but the individual contribution of ligands and their receptors remains elusive.
View Article and Find Full Text PDFBackground: 5-Aminosalicylic acid (5-ASA) may protect against the development of inflammation-associated colorectal cancer. In vitro data suggest that, in colorectal cancer cells, 5-ASA induces cell cycle arrest, but the molecular mechanism leading to this arrest remains to be determined.
Aim: To dissect the signal transduction events that lead to 5-ASA mediated inhibition of proliferation of colorectal cancer cells, focusing on mammalian target of rapamycin (mTOR), a regulator of cell cycle progression.
Quercetin has been shown to act as an anticarcinogen in experimental colorectal cancer (CRC). The aim of the present study was to characterize transcriptome and proteome changes occurring in the distal colon mucosa of rats supplemented with 10 g quercetin/kg diet for 11 wk. Transcriptome data analyzed with Gene Set Enrichment Analysis showed that quercetin significantly downregulated the potentially oncogenic mitogen-activated protein kinase (Mapk) pathway.
View Article and Find Full Text PDFThe aim was to investigate mechanisms contributing to quercetin's previously described effects on cell-proliferation and -differentiation, which contradicted its proposed anticarcinogenic potency. In a 10-day experiment, 40 microM quercetin stabilized by 1 mM ascorbate reduced Caco-2 differentiation up to 50% (p < 0.001).
View Article and Find Full Text PDFCell Mol Life Sci
December 2006
Dietary quercetin intake is suggested to be health promoting, but this assumption is mainly based on mechanistic studies performed in vitro. Previously, we identified rat lung as a quercetin target tissue. To assess relevant in vivo health effects of quercetin, we analyzed mechanisms of effect in rat lungs of a chronic (41 weeks) 1% quercetin diet using whole genome microarrays.
View Article and Find Full Text PDFThe effect of the flavonoid quercetin and its conjugate rutin was investigated on (biomarkers of) colorectal cancer (CRC). Male F344 rats (n = 42/group) were fed 0, 0.1, 1, or 10 g quercetin/kg diet or 40 g rutin/kg diet.
View Article and Find Full Text PDFThe effect of the dietary flavonoid quercetin was investigated on proliferation and differentiation of the human colon cancer cell line Caco-2. Confluent Caco-2 monolayers exposed to quercetin showed a biphasic effect on cell proliferation and a decrease in cell differentiation (0.001
Objectives: We conducted population specific confidential enquiries among immigrants who had never experienced hemoglobinopathies, to study the reliability of this approach in estimating the wish for primary prevention by prenatal diagnosis and selective abortion.
Methods: We collected data from Surinamese Hindustanis (n = 119), Surinamese and Antillean Afro-Americans (n = 105) and North Africans (mainly Moroccans) (n = 102), living in Holland. We also interviewed 105 informed individuals of different ethnicities, all members of the multi-ethnic patients and carriers' organization 'OSCAR Nederland'.
Quercetin is a dietary polyphenolic compound with potentially beneficial effects on health. Claims that quercetin has biological effects are based mainly on in vitro studies with quercetin aglycone. However, quercetin is rapidly metabolized, and we have little knowledge of its availability to tissues.
View Article and Find Full Text PDFDecreased phosphorylation of focal adhesion kinase and paxillin is associated with loss of focal adhesions and stress fibers and precedes the onset of apoptosis (van de Water, B., Nagelkerke, J. F.
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