Screening of differentially expressed Gene(S) and low Penetrance Cancer Susceptibility genes in Colorectal Cancer for Biomarker development

This project studied and screened for differentially expressed genes and low-penetrance cancer susceptible genes in Malaysian patients with colorectal cancer in order to identify potential biomarkers for colorectal cancer detection. A total of 1140 healthy and 246 cancer blood or tissue samples were collected and analysed. A series of differentially expressed genes were identified in colorectal cancer tissues using molecular approaches. STK1S and XRCCl were among the identified differentially expressed genes. Using STK1S and polymerase chain reaction technology, a kit was developed to detect colorectal cancer in this project. Further investigation on STK1S polymorphisms at Phe31 and ValS7 using genomic DNA extracted from blood revealed no significant risk to colorectal cancer in the studied samples. However, single nucleotide polymorphism occurrence at Arg194 of XRCCl showed increased risk to gastrointestinal cancer significantly. Further analyses on other identified genes in this study showed promising results and need to be further developed into biomarkers for colorectal cancer. Four of these potential biomarkers were ribosomal genes. The expression levels of these genes clearly discriminate colorectal cancer from non-colorectal cancer samples, indicating the potential to use as a sensitive and specific noninvasive pre-selection modality for identifying individuals at risk for col 0 recta I cancer. Further development of the kit by a combination of these biomarkers may promise to become a more suitable and affordable means of prevention and early detection of col 0 recta I cancer that can be applied as a routine health check for greater patient compliance and public health benefits