A microRNA-related single nucleotide polymorphism of the XPO5 gene is associated with survival of small cell lung cancer patients

MicroRNA (miRNA)‑related single nucleotide polymorphisms (miR‑SNPs) in miRNA processing machinery genes affect cancer risk, treatment efficacy and patient prognosis. A miR‑SNP of rs11077 located in the 3'UTR of miRNA processing machinery gene XPO5 was examined in small cell lung cancer (SCLC) patients to evaluate its association with cancer survival. A total of 42 patients were enrolled in the present study and genotyped for rs11077 and survival was assessed using the Kaplan‑Meier method, as well as univariate and multivariate analyses. The AA genotype of rs11077 was identified for its significant association with better survival time (P=0.023). In addition, rs11077 was found to associate independently with overall survival in SCLC patients by multivariate analysis (relative risk 2.469; 95% CI, 1.088‑5.603; P=0.031). The findings of this study suggest that although miR-SNP studies for miRNA processing machinery genes are still at an early age, miR-SNPs have an impact on cancer survival. In conclusion, a miR-SNP in the 3'UTR region of the XPO5 gene was identified as an independent prognostic marker for survival of advanced SCLC patients.