Project description:In the proposed study, investigators will conduct a 90-day dietary intervention study in human subjects. Thirty individuals at risk for adenomatous colon polyp formation will be randomized to receive a calcium and multi-mineral-rich natural product (Aquamin) or a comparable level of calcium alone. There will also be a placebo group. Prior to ingesting the study agents and following the course of treatment, colonic biopsies will be obtained by sigmoidoscopy and quantitatively examined for markers of growth and differentiation. In this study, metabolomic and microbial profiles will also be generated from fecal and colon mucosal samples taken at baseline and study endpoint.
Project description:Colorectal cancer (CRC) is one of the most prevalent cancers affecting humans, with a complex genetic and environmental aetiology. Unlike cancers with known environmental, heritable, or sex-linked causes, sporadic CRC is hard to foresee and has no molecular biomarkers of risk in clinical use. One in twenty CRC cases presents with an established heritable component. The remaining cases are sporadic and associated with partially obscure genetic, epigenetic, regenerative, microbiological, dietary, and lifestyle factors. To tackle this complexity, we should improve the practice of colonoscopy, which is recommended uniformly beyond a certain age, to include an assessment of biomarkers indicative of individual CRC risk. Ideally, such biomarkers will be causal to the disease and potentially modifiable upon dietary or therapeutic interventions. Multi-omics analysis, including transcriptional, epigenetic as well as metagenomic, and metabolomic profiles, are urgently required to provide data for risk analyses. The aim of this article is to provide a perspective on the multifactorial derailment of homeostasis leading to the initiation of CRC, which may be explored via multi-omics and Gut-on-Chip analysis to identify much-needed predictive biomarkers.
Project description:Our studies in mice have suggested that the immunological microenvironment of preneoplastic lesions could determine their fate toward neoplasia or regression. A role for gastrointestinal tract bacteria antigens in modulating cancer-related immune responses in the tumor micro- and macro-environment is emerging, thus opening new possibilities for colon cancer prevention.
Project description:Smyd3 is a histone methyltransferase implicated in tumorigenesis. Here we show that Smyd3 expression in mice is required but not sufficient for chemically induced liver and colon cancer formation. In these organs Smyd3 is functioning in the nucleus as a direct transcriptional activator of several key genes involved in cell proliferation, epithelial-mesenchymal transition, JAK/Stat3 oncogenic pathways, as well as of the c-myc and b-catenin oncogenes. Smyd3 specifically interacts with H3K4Me3-modified histone tails and is recruited to the core promoter regions of many but not all active genes. Smyd3 binding density on target genes positively correlates with increased RNA Pol-II density and transcriptional outputs. The results suggest that Smyd3 is an essential transcriptional potentiator of a multitude of cancer-related genes. Standard Smyd3-deficient (Smyd3-KO) mice were generated using gene-trap ES cell clones (AS0527 from International Gene Trap Consortium), in which a selection cassette, containing the splice acceptor site from mouse EN2 exon 2 followed by the beta-galactosidase and neomycin resistance gene fusion gene and the SV40 polyadenylation sequence was inserted into the 5th intron of the Smyd3 gene. The resulting mice were devoid of Smyd3 mRNA and protein in all tissues, including liver and colon. For the generation of Smyd3-Tg mice the open reading frame of the mouse Smyd3 cDNA, which contained 3 Flag epitopes at the 3â end was inserted into the StuI site of the pTTR1-ExV3 plasmid (Yan et al, 1990). The 6.8 kb HindIII fragment containing the mouse transthyretin enhancer/promoter, intron 1, Smyd3 cDNA, three Flag epitopes and SV40 poly-A site was used to microinject C57Bl/6 fertilized oocytes. Founder animals were identified by Southern blotting and crossed with F1 mice to generate lines. Specific overexpression in the liver was tested by RT-PCR analysis in different tissues.
Project description:Primary sclerosing cholangitis (PSC) is a chronic, fibroinflammatory, progressive cholangiopathy. In a clinically significant proportion of patients, the disease course of PSC is punctuated by carcinogenesis, namely cholangiocarcinoma, gallbladder carcinoma, hepatocellular carcinoma, and/or colorectal carcinoma. Indeed, malignancy is arguably the most consequential sequela and the cause of nearly 50% of deaths in patients with PSC. This statistic is multifactorial, relating partly to the premalignant nature of PSC, challenges in diagnosis due to obscuration of cancer by the inflammation and fibrosis inherent to PSC, and the unpredictability of which type of cancer will develop in PSC and when. Here, in the second of a 2-part series, we review cancer risk, prevention, and surveillance in patients with PSC. We also discuss potential cancer surveillance strategies in PSC and, where evidence is limited, make pragmatic recommendations based on current data and expert opinion.