Identification of expression quantitative trait loci of RPTOR for susceptibility to glioma.

Expression quantitative trait loci (eQTLs) have been recognized to be more likely to associate with complex diseases including cancer. As an essential scaffold for MTOR complex 1, RPTOR is necessary for the MTOR-catalyzed phosphorylation. This study examined the associations between the eQTLs of RPTOR and glioma susceptibility. The eQTLs of RPTOR were obtained from GTEx eQTL Browser. Associations were estimated by logistic regression models. On the basis of analysis of 138 cases with glioma and 327 cancer-free population controls, we demonstrated that the eQTL of RPTOR, rs7502563, was significantly associated with a decreased glioma risk [odds ratio (OR) = 0.59, 95 % confidence interval (CI) = 0.38-0.89, P = 0.0123] in a dominant manner. Stratified analyses indicated that the association between rs7502563 and glioma was more pronounced in females (OR = 0.40, 95 % CI = 0.20-0.80, P = 0.0091), older subjects (OR = 0.47, 95 % CI = 0.26-0.86, P = 0.0135), and subjects with high-grade glioma (OR = 0.45, 95 % CI = 0.27-0.77, P = 0.0031). Moreover, an interest gradual decrease in OR with higher grade glioma was observed. Further analysis of the extracted data from GTEx eQTL Browser found that rs7502563 G allele was associated with significantly higher expression of RPTOR in all HapMap populations. Our results demonstrate for the first time that the eQTL of RPTOR, rs7502563, is susceptible to glioma.