Polymorphism of MMP-9 gene is not associated with the risk of urinary cancers: Evidence from an updated meta-analysis

Objective Matrix metalloproteinases 9 (MMP-9) is a zinc-dependent gelatinase, which could decrease the expression of extracellular matrix proteins and influence the metastatic behavior of tumors. In order to draw a comprehensive and precise result about the relationship of MMP-9 and urinary cancers, we presented the current meta-analysis. Methods We searched the PubMed, EMbase, Web of Science, CBM, CNKI and Wanfang databases, the cited references were also manually searched again, covering all the papers published until August 2018. Quality assessment was conducted using the Newcastle–Ottawa Scale. All the meta-analysis was conducted with Stata version 12.0 software to assess the strength of the association. Linkage disequilibrium (LD) analyses of gene polymorphisms and in-silico analysis of MMP-9 expression were also conducted to illustrate the relationship. Results 17 case-control studies comprise of more than 6154 cases and 6330 controls were enrolled and analyzed. After analyzed, we found that there is no significant association between rs3918241, rs2250889, rs17576 and rs17577 of MMP-9 and urinary cancers. LD analysis uncovered a significant LD between rs3918241 and rs17577 in CEU, CHBC CHBC ESN: r2 = 0.74; JPT: r2 = 0.77), as well as a remarkable LD between rs17576 and rs2250889 in CHBC JPT: r2 = 0.82). Furthermore, in-silico results indicated that the expression of MMP-9 in cancer tissue was higher than that in normal tissue in prostate cancer (Transcripts Per Kilobase Million (TPM) = 7.14 vs. 1.36, P Conclusions rs3918241, rs2250889, rs17576 and rs17577 polymorphisms of MMP-9 are not associated with altered risk of urinary cancer. More studies with large sample size focused on the combined effect of two or more polymorphisms of MMP-9 are necessary in the future.