OBJECTIVETo study the different proportions of intermediate epithelial cells in human prostate cancer tissue and their clinical significance.

METHODSWe performed immunohistochemical staining for Cytokeratin 5 (CK5) and Cytokeratin 8 (CK8) on 60 samples of human prostate cancer, determined the proportions of intermediate epithelial cells in the cancer tissue, and classified the samples into 2 types, one with a majority of intermediate epithelial cells (CaP-INT, n = 32), and the other composed mostly of luminal epithelial cells (CaP-LUM, n = 28). Then we compared the 2 types of prostate cancer in the expression of the androgen receptor (AR), age of the patient, serum t-PSA, prostate volume, Gleason score, clinical stage, androgen resistance, and incidence of distant metastasis.

RESULTSCaP-INT showed a significantly lower expression of AR ([24.42 +/- 11.41] %) and a higher incidence of distant metastasis (n = 14) than CaP-LUM ([77.21 +/- 10.22] % and n = 4) (P < 0.05). In the CaP-INT group, 6 of the 26 endocrinologically treated cases developed into androgen-independent prostate cancer (AIPC), while in the CaP-LUM group, only 1 out of 23 (P < 0.05). The former also showed remarkably higher clinical stages than the latter (P < 0.05), but no significant differences were found in age, serum t-PSA, prostate volume and Gleason score between the two groups (P > 0.05).

CONCLUSIONA higher proportion of intermediate epithelial cells may lead to increased invasiveness and metastasis of human prostate cancer.