Abstract C051: Deciphering the role of stress-survival pathway genes and mutations in Hispanic colorectal cancer disparities

• Published in: Cancer epidemiology, biomarkers & prevention biomarkers & prevention, 2023-12, Vol.32 (12_Supplement), p.C051-C051
• Main Authors: Roy, Sourav, Grajeda, Brian I., Khan, Md Zahirul Islam, Basnet, Urbashi, Nair, Soumya
• Format: Article
• Language: English
• ISSN: 1538-7755; 1538-7755
• DOI: 10.1158/1538-7755.DISP23-C051

This study aims to determine the role of stress-survival pathway (SSP) genes and the associated mutations in Hispanic colorectal cancer (CRC) disparities, particularly in young and late-stage Hispanic CRC. CRC is the second most-deadliest among all cancers and the third leading cause of cancer in the United States (US).  An overall reduction in CRC cases among individuals aged 50 and older has been reported, albeit there is an alarming rise in the incidence of early-onset (patients under the age of 50) CRC. The increase in the early onset of CRC is concerning as these cases tend to appear with higher pathologic grades and have a higher risk of recurrence and metastasis. The incidence of early-onset CRC is almost two times in Hispanics (16.5%) when compared to that in non-Hispanic White (NHWs; 8.7%). Access to health care for Hispanics is limited, as a result, they also tend to present with later-stage CRC when compared to NHWs (32% versus 19% of Stage IV), which likely accounts for their inferior age-adjusted survival after CRC diagnosis. Since Hispanics have the highest percentage of young people and comprise ~18% of the US population, the rising incidence of early-onset and late-stage detection of CRC among Hispanics coupled with the rapid growth in this segment of the population makes it imperative to correctly assess the causes behind the observed disparities in Hispanics with early-onset and late-stage CRC. Our previous study, using in-silico analyses of CRC datasets, helped us identify twenty-eight oxidative stress-response and apoptosis-associated genes that are expressed differently in CRC when compared to normal colon tissues. Expressions of these SSP genes (mRNA and protein levels) were validated in CRC cell lines, cDNA arrays, and human colon cancer tissue microarrays (TMAs). Finally, we have confirmed the differential expression of all twenty-eight transcripts in Hispanic and NHW CRC, and corresponding normal adjacent to the tumor (NAT) tissues. Interestingly, we have identified distinct transcripts that are differentially expressed in Hispanics with early-onset (PDCD2L, CDK1, and PRDX4) and late-stage (CCNB1, CDK4, CHEK1, and MCM10) CRC. We have also identified the mutations associated with the SSP genes by analyzing the ClinVar and NHGRI-EBI GWAS databases. These findings have laid the foundation to characterize further, the roles played by these genes in the molecular basis for Hispanic CRC disparities at early-onset and late stages. Differe