Background: Angiogenesis is a proliferative process resulting in the development of new blood vessels from existing endothelial cells and is considered crucial for tumor growth and metastasis. Tumor angiogenesis can be quantified by microvascular density (MVD), which is evaluated in highly vascularized tumor areas (hot spots) by immunohistochemical assays using CD34 and CD31 pan-endothelial antibodies. More recently, CD105 has been successfully used for some tumor types because it could discriminate neovascularization. The expression of CD34 and CD105 in hepatocellular carcinomas (HCC) and hepatic precancerous lesions has been reported-although the results for CD105 are controversial-but to the best our knowledge, CD105 has not been previously investigated in dysplastic nodules (DN). We investigated and compared MVD-CD34 and MVD-CD105 immunoexpression in tissues containing different stages of hepatocarcinogenesis, including DN.
Methods: A total of 31 regenerative nodules (RN), 26 DN and 25 small HCC from explants were used for immunohistochemical tests with CD34 and CD105 antibodies. Antibody expression was quantified by computerized image analysis measurement of MVD, areas containing highly positive endothelial cells within the nodules.
Results: The median MVD for CD34 was higher in HCC than in DN and RN (p < 0.01), and was higher in DN compared with RN (p = 0.033). In contrast, MVD with CD105 was higher in RN, and the difference was significant in RN and DN compared with HCC (p = 0.019 and p = 0.012, respectively). When MVD with CD34 and CD105 were compared within a single group, there was a significant predominance of CD105 in RN and DN (p < 0.01). In addition, MVD-C34 in HCC predominated compared with MVD-CD105, but the difference was not statistically significant (p = 0.128).
Conclusions: This study identified a close relationship between CD105 and liver cirrhosis, and that CD34 antibody is a good endothelial marker for hepatic carcinogenesis. There was no difference between the use of CD105 and CD34 antibodies in preneoplastic lesions.