Interleukin-6 gene-174 G/C promoter polymorphism is not associated with multiple myeloma susceptibility: evidence from meta-analysis: A systematic review and meta-analysis

PURPOSE: Presently, whether interleukin-6 (IL-6) gene-174 G/C promoter polymorphism is correlated to the susceptibility of multiple myeloma (MM) remains controversial. For this reason, the method of meta-analysis was applied to exploring the association between IL-6 gene-174 G/C promoter polymorphism and MM. METHOD: Two independent researchers systematically searched PubMed, EMBASE, Google academic, Cochrane Library and Chinese literature databases to screen case-control studies on IL-6 gene-174 G/C promoter polymorphism and MM susceptibility. The retrieval period was limited from the formation of the database to January 2020, and data analysis was conducted by employing Stata 11.0 software. RESULT: Seven articles were ultimately included in the present study, including 594 MM patients and 681 controls. Integration analysis exhibited that compared with GC or CC genotype, GG genotype did not increase MM susceptibility (OR = 0.95, 95% CI 0.75–1.22; OR = 0.79, 95% CI 0.52–1.19, respectively). Further, in comparison with CC genotype, GC genotype also presented no effect on increasing MM susceptibility (OR = 0.79, 95% CI 0.53–1.16), while compared with GC+CC genotype, GG genotype had no significant relationship with MM susceptibility (OR = 0.94, 95% CI 0.75–1.19). In subsequent analysis, an observation was made that allele G or C was not related to MM susceptibility (OR = 0.92, 95% CI 0.76–1.12). Funnel chart and Begg test did not reveal publication bias in the included articles. CONCLUSION: The results of the present study advocate that there is no testimony to support the relationship between IL-6 gene-174 G/C promoter polymorphism and MM susceptibility.