High expression of ASPM correlates with tumor progression and predicts poor outcome in patients with prostate cancer

Abnormal spindle microtubule assembly (ASPM) gene was known to be linked with poor clinical prognosis in various tumors. However, the clinical significance of ASPM in prostate cancer (PCa) has not yet been understood. The purpose of this study was to determine the association of ASPM with tumor progression and prognosis in PCa patients. The expression of ASPM at protein level in human PCa and non-cancerous prostate tissue was detected by immunohistochemical analysis, which was further validated by using microarray-based dataset (NCBI GEO: GSE21032 and The Cancer Genome Atlas (TCGA) dataset) at mRNA level. Subsequently, the association of ASPM expression with the clinicopathological characteristics of patients with PCa was then statistically analyzed. Immunohistochemistry and dataset analyses revealed that ASPM expression was significantly increased in the PCa tissues with high Gleason score. Additionally, as showed by two datasets, ASPM expression was significantly high expressed in the PCa tissues when compared with the non-cancerous tissues, especially in advanced PCa pathological stage. The upregulation of ASPM mRNA expression in the PCa tissues significantly correlated with the presence of tumor metastasis, shorter overall survival and prostate-specific antigen (PSA) failure. Furthermore, both univariate and multivariate analyses showed that the upregulation of ASPM was a potential predictor of poor biochemical recurrence (BCR)-free survival. Our data suggest that ASPM may play an important role in the progression of PCa. More importantly, the increased expression of ASPM may potentially predict poor BCR-free survival in patients with PCa.