Association between VEGF Gene Polymorphism -634G>C and Risk of Colorectal Cancer

Abstract

BACKGROUND: Genetic and environmental factors play an important role in the pathogenesis of colorectal cancer. Angiogenesis is a central process in carcinogenesis and is affected by vascular endothelial growth factor (VEGF). Several genetic variations, such as polymorphism, may alter VEGF expression and influence the risk of colorectal cancer. AIM: The objective of this study was to determine the association between VEGF gene polymorphism -634G>C and risk of colorectal cancer. METHODS: A cross-sectional study was conducted at Haji Adam Malik general hospital and its sister hospitals. Subjects were obtained by consecutive sampling. Inclusion criteria for case and control groups were patients with colorectal cancer and healthy subject, respectively, aged 18 years or older and willing to participate in the study. Exclusion criteria were patients with systemic comorbidities or malignancies in other organs. Each subject undergoes an interview, colonoscopy, biopsy, serum VEGF level measurement, and VEGF polymorphism -634G>C evaluation. RESULTS: Eighty subjects were enrolled and distributed into case and control groups. Males were dominant in both groups, with a mean age of older than 55 years. Most lesions were in the rectum and 45% of subjects had moderately differentiated cancer. The median serum VEGF level in the case group was higher than the control group (2,175.1 pg/mL vs. 253 pg/mL; p < 0.001). VEGF gene polymorphism -634G > C was associated with the risk of colorectal cancer (p = 0.048). GG and GC genotypes had 1.89 times higher risk of colorectal cancer compared to the CC genotype. GG genotype and G allele had the highest serum VEGF levels. CONCLUSION: There is an association between VEGF gene polymorphism -634G>C and risk of colorectal cancer in this study.