OBJECTIVETo investigate the expression of EphA2 and EphrinA1 and its relationship with angiogenesis in renal cell carcinoma and its relevance to clinicopathologic features.

METHODSThe expression of the EphA2 and EphrinA1 was detected by immunohistochemistry (IHC) in the tissues samples from 68 renal cell carcinomas and 24 normal kidneys, and quantitatively analyzed. The microvessel density (MVD) was determined by CD34 immunostaining of microvascular endothelial cells. Statistical analysis was performed using the software SPSS (version 13.0).

RESULTSThe expression of EphA2, EphrinA1 and MND in the cancerous tissues were significantly higher (P<0.01) than that in the normal ones. Significantly increased expression of EphA2, EphrinA1 and MVD (P<0.01) was detected in cancer tissues with higher grade differentiation, more advanced stage and more lymph node metastasis, respectively (P<0.05 for each group). Expression of the EphA2 and EphrinA1 protein was shown to be positively associated with the MVD assessed by Spearman's correlation and factor analysis (r=0.555, r=0.485, P<0.01). The MVD was also significantly correlated with the diameter of the tumor (P<0.01).

CONCLUSIONEphA2 and EphrinA1 are highly expressed in renal cell carcinoma, and positively correlated with histological differentiation, clinical stage and angiogenesis in the cancer.