Increased expression of NKX3.1 in benign prostatic hyperplasia.

ABSTRACT

OBJECTIVES: To establish the role of the NKX3.1 gene in the development of benign prostatic hyperplasia by comparing the expression of NKX3.1 in messenger ribonucleic acid (mRNA) and protein levels in young adult prostate and BPH tissues. METHODS: Normal prostate tissue samples (n = 4) were obtained from prostate biopsies of patients less than 40 years of age who underwent diagnostic cystoscopy for microscopic hematuria. Benign prostatic hyperplasia tissues (n = 12) were obtained from patients who underwent transurethral prostate resection for bladder outlet obstruction. The RNAs isolated from these tissue samples were analyzed with quantitative reverse transcriptase polymerase chain reaction; the proteins were analyzed with Western blotting and immunohistochemistry. RESULTS: The mean NKX3.1 mRNA transcript expression was 19.17 +/- 3.05 vs 1.24 +/- 1.32 in BPH and normal tissues, respectively, and NKX3.1 protein expression of BPH was approximately 2.4-fold higher than in normal prostate tissue. Reverse transcriptase polymerase chain reaction and Western blot analyses revealed that NKX3.1 gene expression in BPH patient tissues were higher compared with normal prostate tissues. Immunohistochemistry results indicated that most of the BPH tissues stained diffusely, and there was no BPH tissue that lacked NKX3.1 expression. CONCLUSIONS: NKX3.1 expression is elevated in BPH tissues when compared with normal tissues, which may be important in the development of BPH.