NM23 gene expression in human prostatic carcinomas and benign prostatic hyperplasias: Altered expression in combined androgen blockaded carcinomas

Purpose: To investigate whether NM23 (nm23-H1, nm23-H2), a metastasis suppressor gene family, is a molecular marker indicative of metastatic potential of localized carcinoma of the prostate (CaP). Previously, we found decreased nm23-H2 expression correlated with an increase in stage, and here we have expanded the cohort. Materials and Methods: Eighty prostate tissue samples from patients with CaP and benign prostatic hyperplasia (BPH) were examined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) for NM23 gene expression. Samples were grouped according to stage, grade and whether the patient received combined androgen blockade (CAB) prior to surgery. Results: We could not confirm our initial results of an inverse correlation of nm23-H2 expression levels with grade. However, two significant results were found after CAB: 1) nm23-H1 expression was reduced (p = 0.003), and 2) nm23-H2 expression across stage and grade was uniformly higher (p = 0.003) than in untreated samples. Conclusion: NM23 appears not to be a useful molecular marker of metastatic potential in CaP. The altered gene expression after CAB may relate to a cancer cell subpopulation insensitive to apoptosis induced by hormone withdrawal.