HLA-G And Fas Ligand Expression In Clear Cell Renal Cell Carcinoma

Objective: Conventional (clear cell) renal cell carcinoma (ccRCC) is unsusceptible to chemotherapy, radiotherapy and hormone therapy. The effect of immunotherapy is far from satisfaction, it may be attributed to tumor evade immune surveillance which was caused by expressing some immunosuppressive molecules in RCC. In this research we investigate the expression of the tow kinds of immunosuppressive molecules, nonclassical human leucocyte antigen class HLA-G and Fas ligand (FasL), in the ccRCCs. Methods: 60 cases of ccRCC's formalin-fixed, parafflin-embed surgical specimens were examined by immunohistochemistry. Data were analysed by SPSS software. Results: There were no expression of HLA-G in the normal renal tissue. HLA-G was detected in 40 ccRCC cases (66.7%),FasL was detected in 36 cases (60%). Both the HLA-G and FasL were positive in 31 cases (51.7%) and were negative in 15 cases (25%).Both the HLA-G and FasL expression level were increased after the ccRCC cells invaded the vessel or lymphatic node. The incidence and level of HLA-G were correlated with tumor grade or stage (P<0.01). The incidence of FasL expression were correlated with the tumor grade (P<0.05) but the level of FasL expression were correlated with the tumor stage (P<0.01). Conclusions: The expression of HLA-G and FasL were correlated with the tumor stage, grade and metastasis of ccRCC. The mechanisms of high expression of immunosuppressive molecules in the advanced stage ccRCCs require further investigation.