Expression profile of zinc channels in human renal cell carcinoma after Temsirolimus treatment

Abstract

INTRODUCTION: Zinc is an essential trace element for cell proliferation and growth. Cellular Zn is regulated of by ZnT and ZIP family channels but its mechanism still not completely understood. Renal cell carcinoma (RCC) is one of the most malignant renal tumors. The RCC clear cell pathological subtype is associated with the VHL gene mutation, that is responsible for its aggressiveness. Temsirolimus (TEM), an antineoplastic drug used in the treatment of RCC, is a selective inhibitor of mTOR. OBJECTIVES: To evaluate the expression of zinc channels in clear cell renal carcinoma cell line with and without TEM treatment. MATERIALS AND METHODS: The MTS (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium-bromide) assay was used define IC50. The expression of ZnT1, ZnT4, ZIP11 and ZIP14 channels from the HK-2, 786-0 and 786-0/TEM cells was evaluated by real-time PCR and Western blot analysis. DISCUSSION AND RESULTS: The IC50 dose was 10μM. Gene expression analysis comparing Hk-2 and 786-0 cell lines revealed decreased levels of ZnT1 of 79.20±3.58% (P< 0.0001 vs HK-2) and an increase for the ZIP 11 of 243.3±62.84% (P< 0.01 vs HK-2). The comparison between 786-0 with and without TEM treatment showed decreased levels of ZnT1 of 34.03±20.45% (P< 0.05 vs 786-0), ZnT4 of 92.82±0.72% (P< 0.0001vs 786-0), ZIP14 of 11.24% (P< 0.01 vs 786-0) and ZIP11 of 95.96±0.54% (P< 0.0001 vs 786-0). Western blot data corroborated the real time results. CONCLUSION: There is a difference in the Zn channel expression profiles between HK-2 and 786-0. The treatment with TEM modulates the expression of these channels.