Abstract SS01-02: Microbial sulfur metabolism and colorectal cancer risk

Abstract

Abstract Both sporadic and IBD-associated colon cancer result from multifactorial interactions among common alleles of polymorphic genes and insults in the intestinal environment. We are examining the extent to which bacterial-derived hydrogen sulfide may serve as a proinflammatory and genotoxic insult that modifies colon cancer risk. Data will be presented which demonstrate that the human colonic mucosa is persistently colonized by bacteria capable of generating sulfide from both inorganic and organic sulfur sources along with evidence that sulfide activates molecular pathways that underlie epithelial inflammation and hyperplasia, a phenotype common to both ulcerative colitis and colorectal cancer. Our published studies will also be summarized, which demonstrate that exogenous sulfide is a potent genotoxin that acts independent of cellular metabolism and mediated by free radicals. These observations highlight the possible role of sulfide as an intestinal insult that, given a predisposing genetic background, may lead to genomic instability or the cumulative mutations characteristic of colorectal cancer. Citation Format: H. Rex Gaskins. Microbial sulfur metabolism and colorectal cancer risk. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr SS01-02. doi:10.1158/1538-7755.DISP13-SS01-02