Abstract
The second most frequent cancer in the world is prostate cancer. Incidence and mortality are respectively 30.7 and 7.7 per 100,000 people. While late-stage cancer has a survival rate of 30%, earlystage cancer has a 5-year survival rate of 96.8%. In Thailand, the incidence of prostate cancer is 14.6 per 100,000 population. The fifth most frequent cancer in the world is colon cancer. Per 100,000 people, the incidence and mortality are 11.4 and 5.4, respectively. It is the seventh most prevalent cancer in Thailand. Risk factors for these cancers include age, smoking, drinking alcohol, having a family history of the disease, and race. Increases in disease incidence and progression are associated to BRCA1 gene mutations. DNA damage repair will be unsuccessful if the BRCA1 gene was altered. The errorprone will occur, which leads to carcinogenesis. As a result, BRCA1 mutation is highly associated with the etiology of prostate cancer and colon cancer. It is essential to understand the relationship between the BRCA1 mutation and prostate cancer and colon cancer in terms of carcinogenesis, treatment response, and prognosis. A unique variant in cancer cells may be beneficial for targeted therapy and personalized medicine, gene variation investigation crucial. Currently available next generation sequencing would be utilized to investigate any alterations to a gene or genome that might affect the pathophysiology and management of cancer. Twelve samples, comprising three cases of colon cancer and nine cases of prostate cancer, were used in this study, and their whole exomes were sequenced. Five of all these cases are clinical staged, while the other cases' data is not relevant. This research revealed seven SNP-missense mutations that are common in 8 out of 12 cases. It contains the missense SNVs rs799917 G>A, rs16942 T>C, rs16941 T>C, and rs1799966 T>C. InDel mutation is identified in nine cases. Unfortunately, all the InDel mutations are in the particular genetic intron. The investigation included a LOH analysis. Combining NGS information with LOH results revealed that 5 out of 12 sample, including B0966, B2666, B3629, B6643, and B9546 have both LOH at D17S855 and D17S250 and SNV rs16941 T>C missense mutation. The knowledge can be used to identify biomarkers for disease diagnosis, prognosis, and responsiveness prediction. Furthermore, it can be used for both current and future drug development.
