Evaluation of the association between the −1304T>G polymorphism in the promoter of the MKK4 gene and the risk of colorectal cancer: a PRISMA-compliant meta-analysis

Rui Bai, Cheng Yuan, Fuxiang Zhou, Lihua Ni, Yan Gong, Conghua Xie


Background: Colorectal cancer (CRC) is one of the most common cancers in China. Mitogen-activated protein kinase kinase 4 (MKK4) regulates tumorigenesis as a component of the MKK4 pathway. A number of studies have suggested a correlation between the MKK4 −1304T>G polymorphism and the risk of CRC. However, the results are still controversial. Therefore, we conducted a meta-analysis to obtain a more accurate assessment of the association between the MKK4 −1304T>G polymorphism and the risk of CRC.
Methods: Systematic literature searches were performed using PubMed, Embase, Cochrane Library, and CNKI. Four trials, including 1,255 cancer cases and 1,181 controls, were recruited in our study to assess the relationship of the MKK4 −1304T>G polymorphism with the risk of CRC.
Results: Four studies met our inclusion criteria and were finally included in the analysis, involving 1,255 cancer patients and 1,181 controls. Our meta-analysis revealed that the MKK4 −1304T>G polymorphism could reduce the risk of CRC (G vs. T: OR, 0.60, 95% CI: 0.48–0.76, P<0.0001; GG vs. TT: OR, 0.43, 95% CI: 0.29–0.62, P<0.0001; GG vs. TT + TG: OR, 0.50, 95% CI: 0.34–0.72, P=0.0003; TG + GG vs. TT: OR, 0.62, 95% CI: 0.53–0.73, P<0.0001; and TG vs. TT + GG: OR, 0.70, 95% CI: 0.59–0.82, P<0.0001).
Conclusions: In conclusion, our meta-analysis showed that the MKK4 −1304T>G polymorphism was associated with the susceptibility to CRC. In the future, large and well-designed case-control studies are needed to validate our findings.