Expression of CEACAM1 and CD105 in Renal Cell Carcinoma and Its Correlation with Microvessel Density

We investigated expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and endoglin (CD105) in renal cell carcinoma (RCC), and its potential role in predicting tumor growth and progression. A total of 47 RCC specimens and 15 adjacent normal kidney tissues were obtained. Expression of CEACAM1 and CD105 was assessed by immunohistochemistry. Microvessel density (MVD) was counted under the microscope by labeling the endothelial cells with biomarker CD34. The positivity of CEACAM1 expression in RCC (42.6%) was significantly lower than that in the normal kidney (73.%, P = 0.038). In contrast, the positivity of CD105 expression was significantly higher in RCC (78.7%) compared to that in the normal kidney (46.7%, P = 0.017). The expression level of CD105 in 47 RCC patients was significantly associated with the clinical stages of RCC (P < 0.05) but not with gender, age, tumor size, or histologic grade. Average MVD in RCC (78.05 ± 16.57) was significantly higher than that in normal tissue (43.62 ± 12.37, P < 0.05), and was significantly higher in RCC patients with advanced histologic grades (P < 0.05) or clinical stages (P < 0.01). In addition, MVD was significantly correlated with CD105 but negatively correlated with CEACAM1. Our findings suggest that down-regulation of CEACAM1 may promote angiogenesis in RCC, and that up-regulation of CD105 may promote RCC progress. MVD may be an indicator of RCC malignancy.