Abstract C35: Differential inflammatory cytokine secretion between African American and Caucasian colon cancer cell lines

Abstract

Abstract Colorectal cancer (CRC) incidence and mortality rates in African Americans (AAs) are up to 38% higher than in Caucasian Americans (CAs). Moreover, our previous studies reported that AAs have hypermethylated DNA regions in inflammatory genes such as NELL1, GDF1, ARHGEF4, and ITGA4; suggesting that AAs have differences in their inflammation patterns when compared to CAs. Therefore, we used two AA tumor-derived cell lines, which were generated in Dr. Williams' laboratory, and two CA tumor-derived cell lines to study the production of the pro-inflammatory IL-8 and anti-inflammatory IL-10 cytokines as they relate to possible differences in the inflammatory response. The inflammatory inducers IL-1B and TNF-alpha as well as Lipopolysaccharide from E. coli were used to mimic colonic inflammatory niches and induce cytokines secretion in these four cell lines. As hypothesized, our results show a significantly higher inflammatory cytokine production of IL-8 in the CA cell lines in response to all the treatments when compared to the AA cell lines. In contrast, secretion of IL-10 between the cell lines was within the same range. We could then propose that AA colon tumors secrete less IL-8 than CA colon tumors as a consequence of their DNA hypermethylated genes and this leads to deficient recruitment of neutrophils and macrophages, key cells for pathogen elimination and T cell activation. Further studies are needed to elucidate the differences in inflammation patterns between AAs and CAs and their role in CRC health disparities. Citation Format: Jenny Elizabeth Paredes Sanchez, Maria Munoz-Sagastibelza, Ji Peing, Laura Martello-Rooney, Jennie Williams. Differential inflammatory cytokine secretion between African American and Caucasian colon cancer cell lines. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C35.