Diagnostic Significance of Overexpression of Golgi Membrane Protein 1 in Prostate Cancer

Abstract

To investigate the diagnostic significance of Golgi membrane protein 1 (GOLM1) expression in prostate cancer. The localization of GOLM1 in prostate cancer cells was detected by immunofluorescence. The GOLM1 expression in prostate cancer cells at the mRNA and protein level was determined by quantitative real-time polymerase chain reaction and Western blot analysis, respectively. A prostate cancer tissue microarray was used to analyze GOLM1 protein expression by immunohistochemistry. The immunofluorescence results demonstrated that GOLM1 was located at the cis-Golgi in the DU145 cells. GOLM1 transcripts and protein were overexpressed in a wide variety of prostate cancer cell lines (DU145, 22RV1, PC-3, and LNCaP). Tissue microarray immunohistochemistry demonstrated that GOLM1 protein staining was occasionally found in the normal prostate gland and benign prostatic hyperplasia, whereas that in prostate cancer was predominantly observed in the cytoplasm of tumor cells. GOLM1 protein was strongly expressed in prostate cancer tissues, and there was a significant difference compared with the normal prostate and benign prostatic hyperplasia cases (P < .05). There were no significant differences between GOLM1 overexpression and pathologic variables of prostate cancer, including histologic grade and pathologic stage (P > .05). Our results suggest that GOLM1 protein is significantly expressed in prostate cancer in comparison with the normal prostate gland and benign prostatic hyperplasia. These findings may suggest that GOLM1 is useful in the diagnosis or therapy of prostate cancer. However, GOLM1 overexpression is not associated with disease stage and grade.