In situ detection of TGF betas, TGF beta receptor II mRNA and telomerase activity in rat cholangiocarcinogenesis

AIM: Initial report on the in situ examination of the mRNA expression of transforming growth factor betas (TGFβs), TGFβ type II receptor (TβRII) and telomerase activity in the experimental rat liver tissue during cholangiocarcinogenesis. METHODS: Rat liver cholangiocarcinogenesis was induced by 3’-methyl 4-dimethylazobenzene (3’Me-DAB). In situ hybridization was used to examine the TGFβs) and TGFβ type II receptor (TβRII) mRNA, in situ TRAP was used to check the telomerase activity in the tissue samples. RESULTS: There was no TGFβs, TβRII mRNA expression or telomerase activity in the control rat cholangiocytes. The expression of TGFβ1, TβRII was increased in regenerative, hyperplastic, dysplastic cholangiocytes and cholangiocarcinoma (CC) cells. The expression of TGFβ2 mRNA was observed in only a part of hyperplastic, dysplastic cholangiocytes. TGFβ3 expression was very weak, only in hyperplastic lesion. There was positive telomerase activity in the regenerative, hyperplastic, dysplastic cholangiocytes, and CC cells. Stroma fibroblasts of these lesions also showed positive TGFβs, TβRII mRNA expression and telomerase activity. CONCLUSION: There were TGFβs, TβRII expression and telomerase activity in hyperplastic, dysplastic cholangiocytes, cholangiocarcinoma cells as well as in stroma fibroblasts during cholangiocarcinogenesis. Their expression or activity is important in cholangiocarcinogenesis andstroma formation.