PinX1 is up-regulated and associated with poor patients' survival in gliomas.

PinX1, a conserved nuclear protein, could maintain telomere integrity and plays an important role in regulating telomerase activity. It has been reported that the expression of PinX1 is down-regulated in some cancer and associated with cancer prognosis. However, the value of PinX1 in gliomas has not been studied. In this study, two independent retrospective gliomas cohorts with the corresponding gliomas tissue microarrays (TMAs) were established to detect the expression level of PinX1 and the correlation of PinX1 expression with the clinicopathological features and the patients' survival. Compared with non-cancerous brain tissues, PinX1 protein levels were remarkably up-regulated in gliomas (P = 0.001), and further increased from benign gliomas tissues to malignant gliomas tissues (P = 0.090). Moreover, high PinX1 expression was significantly positively associated with gliomas WHO grade in the training set (P = 0.019) and the validation set (P = 0.037). High PinX1 expression significantly correlated with a worse 5-year overall (P = 0.016) and disease-specific survival (P = 0.026). Simultaneously, the multivariate COX regression analysis showed that PinX1 was an independent unfavorable prognostic factor for 5-year overall survival (hazard ratio (HR) = 2.078, P = 0.015) and disease-specific survival (HR = 2.429, P = 0.012) after adjusting with age, sex and WHO grade in gliomas. In conclusion, PinX1 expression may serve as a prognostic and predictive biomarker for gliomas.