The expression and evaluation of androgen receptor in human renal cell carcinoma

To investigate the expression of androgen receptor (AR) with clinical and pathologic features in patients with renal cell carcinoma (RCC) and to explore the function of AR using human RCC cells.

The expression of AR was detected by immunohistochemistry in 44 adjacent normal kidney tissues of 120 RCC patients and also in 16 metastatic RCC patients with their respective primary and metastatic tissue samples. The expression of AR was examined by western blot in commonly used human RCC cell lines and normal kidney epithelial cells, and the luciferase assay was performed in those AR-positive RCC cells.

The expression rate of AR was higher in adjacent normal kidney (90.9%) than in RCC tissues (30.0%, P <.001), and it was negatively associated with pT stage and Fuhrman's grade. Specifically, there were 40.7% AR-positive cases in pT1 compared with 8.0% in pT3 (P = .013), and 50.0% of grade I cases were found to be AR positive compared with 12.9% in grade III (P = .008). AR expression was slightly higher in primary RCC tissues (12.5%) than their respective metastases (0%, P = .484). AR strongly expressed in CAKI-2 and OSRC-2 cells with little transactivation, which might indicate that AR in those 2 RCC cells has little function.

Our results suggest that any attempt to investigate the roles of AR in RCC progression might need to combine the detection of AR expression in tissue samples with examining its function to make a correct correlation between AR and RCC progression.