Expression and clinical significance of CD147 in genitourinary carcinomas

CD147/extracellular matrix metalloproteinase inducer (EMMPRIN) expressed by tumor cells stimulates peri-tumorous fibroblasts to produce matrix metalloproteinases (MMPs), thus contributing to tumor invasion and metastasis. To assess its suitability as a potential therapeutic target, as well as its association with the clinicopathologic features and the prognosis of patients, the expression of CD147/EMMPRIN in neoplastic tissues of the genitourinary system were analyzed.

CD147/EMMPRIN expression in 52 patients with renal carcinoma, 58 patients with bladder carcinoma, 101 patients with prostate carcinoma, 17 patients of penis carcinoma, and 17 patients of testis carcinoma were examined by immunostaining on paraffin-embedded tumor specimens using monoclonal antibodies. Then, the association of its expression with clinicopathologic characteristics to the patients' prognosis was analyzed. The RNA interference approach was used to silence CD147/EMMPRIN expression in the human prostate carcinoma cell line LNCAP and human bladder carcinoma cell line J82. The in vitro proliferative ability of CD147/EMMPRIN-deficient cells was determined by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay.

CD147/EMMPRIN was expressed in neoplastic tissues, but not in normal tissues. Positive expression was shown in 42 of 52 (80.77%) of the patients with renal carcinoma, 41 of 58 (70.69%) of the patients with bladder carcinoma, 67 of 101 (66.34%) of the patients with prostate carcinoma, 16 of 17 (94.12%) of the patients with penis carcinoma and testis carcinoma. Positive CD147/EMMPRIN staining was significantly associated with TNM stages and histological subtypes of patients with various urinary carcinomas (P < 0.05). In all five groups, for different expression levels of CD147/EMMPRIN, the patients with a highly positive expression of CD147/EMMPRIN had the poorest prognosis. The siRNA-treated cells exhibited significantly decreased growth ability compared with control cells in vitro.

These results may assist in defining the suitability of CD147/EMMPRIN as a therapeutic target and as a method for predicting a poor outcome in patients with various urinary carcinomas.