Correlation of VEGF +405C/G Polymorphism with Gastrointestinal Tract Cancers Risk: An Updated Meta-Analysis.

Background: The functional polymorphisms of VEGF can affect different cellular processes and play a major role in angiogenesis and tumor development. Several case-control studies have explored the association of VEGF +405C/G polymorphism with GIT cancer risk, however, the results were inconsistent. Therefore, the meta-analysis was conducted to clarify the association.

Methods: Based on the inclusion and exclusion criteria, relevant data were extracted from PubMed, Google Scholar, Web of Science and Science Direct. Twenty three studies comprising 5,656 cases and 6,319 healthy controls were included in the present meta-analysis and the data was analysed by using online MetaGenyo software.

Results: In the present study, no significant association was found in any of the genetic models in overall analysis as well as when data was stratified according to the ethnicity (p>0.05). After performing sub-group analysis on the basis of cancer type, significant association was found with increased risk of developing esophageal cancer under allele contrast, recessive, GG vs. CC and GG vs. GC models (p<0.05). Under overdominant model, VEGF +405C/G polymorphism was significantly associated with decreased risk of developing esophageal cancer (p=0.017) and GG vs. GC model showed a significant association with the risk of developing colorectal cancer (p=0.047) and pancreatic cancer (p=0.010). However, GC vs. CC model showed that VEGF +405C/G polymorphism was significantly associated with reduced risk of pancreatic cancer (p=0.039).

Conclusion: The present updated meta-analysis suggested that VEGF +405C/G polymorphism may serve as a biomarker for determining an individual's risk of esophageal, colorectal and pancreatic cancer.