The effects of calcium-sensing receptor (CASR) gene variants on colorectal cancer (CRC) risk and mortality: a systematic review and meta-analysis

The role of calcium-sensing receptor (CASR) in colorectal cancer (CRC) have been assessed with several studies, but the conclusions were inconclusive. Thus we performed a meta-analysis to evaluate the impact of CASR polymorphisms on CRC risk and mortality. We searched literature from PubMed, Embase, Cochrane Library, and Web of Science databases. The strength of association between the CASR polymorphisms and CRC risk was assessed by calculating odds ratio (OR) with 95% CI. CASR rs1801725 polymorphism was related to an increased risk of CRC (OR = 1.44; 95% CI, 1.08-1.93; P = 0.01). CASR rs1042636 polymorphism was not found to be associated with CRC risk (OR = 0.90; 95% CI, 0.74-1.10; P = 0.32). As for rs1801726 (OR = 0.90; 95% CI, 0.66-1.23; P = 0.51) and rs12485716 (OR = 0.99; 95% CI, 0.88-1.11; P = 0.82), they were also not associated with CRC risk, respectively. CASR rs4678174 polymorphism was significantly related to decreased risk of CRC (OR = 0.91; 95% CI, 0.83-0.99; P = 0.03). However, CASR rs1801725 polymorphism was not associated with CRC mortality risk. In conclusion, this meta-analysis demonstrates CASR rs1801725 polymorphism and rs4678174 polymorphism were significantly related to the risk of CRC.