Overexpression of malignant brain tumor domain containing protein 1 predicts a poor prognosis of prostate cancer.

Malignant brain tumor domain containing protein 1 (MBTD1) is a member of the polycomb group protein family that is associated with tumorigenesis. The present study investigated the role of MBTD1 within defined clinicopathological parameters and the prognosis of patients with prostate cancer (PCa). A human tissue microarray containing samples from 71 patients with PCa and seven healthy donors was employed for immunohistochemistry (IHC). The clinicopathological characteristics and prognostic value of MBTD1 were investigated using a dataset of 499 patients from The Cancer Genome Atlas (TCGA). IHC illustrated that the levels of MBTD1 protein were enhanced and markedly associated with aggressive clinical stage and advanced tumor invasion, distant metastasis and lymph node metastasis in patients with PCa. In the TCGA data set, the level of MBTD1 was found to positively correlate with the prostate-specific antigen level, Gleason score and distant metastasis. The multivariate analysis of Cox regression revealed that the levels of MBTD1 may act as an independent prognostic factor for low non-biochemical, recurrence-free survival. In conclusion, MBTD1 was overexpressed in PCa tissues and is associated with aggressive clinicopathological characteristics. It may therefore act as a novel prognostic factor and diagnostic marker in PCa.