Abstract C110: The role of the S100 family signaling pathway proteins in Hispanic colorectal cancer disparities
Authors: Nair Soumya , Grajeda Brian I , Roy Sourav 
Published: September 2024

Abstract
Colorectal cancer (CRC) is a global health concern, ranking as the second deadliest and third most diagnosed cancer. In the United States alone, it is estimated that there will be 152,810 new cases of CRC in 2024. CRC has an overall survival rate of 90% when detected in its early stages (Stage I/II). However, due to low screening rates, only 39% of CRC patients in the U.S. are diagnosed during the early stage, particularly among the minority groups like Hispanics. This disparity can be attributed to various factors, including limited access to health care facilities and socio-economic barriers. Among Hispanics, CRC diagnosis and screening rate are lower, resulting in a higher incidence of late-stage (Stage III/IV) diagnosis compared to Non-Hispanic Whites (NHW). Only 33% of Hispanics receive timely diagnosis, and merely 49% undergo recommended screening protocols, in comparison to a diagnosis rate of 35% and screening rate of 58% in NHW. Addressing this health disparity emphasizes the urgent need for targeted interventions to improve early screening and diagnosis within the Hispanic population. We hypothesize that genetic factors across different ethnicities/races may influence gene expression patterns during various stages, thereby contributing to CRC tumorigenesis and progression. To enhance the chances of identifying markers for early detection and diagnosis among Hispanics, we aim to identify new ethnicity-specific transcriptomic profiles. RNA sequencing of Hispanic CRC, NHW CRC and their respective normal tissues adjacent to the tumor (NAT), revealed unique sets of differentially expressed genes (DEGs) with a log2 foldchange of ≥ 2.0 and ≤ -2.0 and p-adjusted value ≤ 0.05 in Hispanic (1831) and NHW (1225) CRC populations compared to their respective NATs. Further analysis identified DEGs specific to early (1012) and late (765) stages of CRC within the Hispanic population, as compared to the respective stages in the NHW. Ingenuity Pathway Analysis (IPA) was used to uncover significant DEGs associated with the S100 family signaling pathway in Hispanic CRC samples. Previous studies have indicated the involvement of the S100 family proteins and their signaling pathways in CRC development, progression, metastasis, and drug resistance through interactions with WNT/β-catenin, RAGE, MAPK and NF-κβ signaling pathways. Our investigation of DEGs within the S100 signaling pathway and their interaction with downstream effectors suggests differential expression of genes crucial in cellular processes, including matrix metallopeptidases (MMP), mitogen-activated protein kinases (MAP2K) and Wingless-related integration site (WNT) family proteins. Exploring these proteins and their downstream effectors in Hispanic CRC tissues and organoids would elucidate specific functional attributes influencing CRC progression. Understanding the interaction of proteins identified in this study may serve as potential ethnicity-specific biomarkers or targets for the development of novel therapeutic interventions for early-stage CRC diagnosis in Hispanics.
Citation Format: Soumya Nair, Brian I Grajeda, Sourav Roy. The role of the S100 family signaling pathway proteins in Hispanic colorectal cancer disparities [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C110.