Aim: To investigate the role of Wnt/beta-catenin signaling transduction pathway in rat hepatocarcinogenesis.
Methods: The mRNAs of Wnt1, beta-catenin, APC, cyclin D1 and c-myc genes were amplified by using of semiquantitative reverse transcription polymerase chain reaction (RT-PCR) from normal rat livers, atypical hyperplasia livers and hepatoma tissues, respectively. Then the proteins expression of beta-catenin, APC and cyclin D1 was examined by immunohistochemical staining.
Results: In normal rat livers, the mRNAs of Wnt1, cyclin D1 and c-myc genes were not detected and only beta-catenin protein was observed to have low expression at cellular membrane. However, 14 weeks after cancer induction in atypical hyperplasia livers, beta-catenin protein and APC protein were accumulated in cytoplasm. Meanwhile, cyclin D1 protein was detected in cytoplasm and/or nucleus in some cells. 16 weeks after cancer induction in hepatoma tissues, the mRNAs and protein expression of beta-catenin, APC, cyclin D1 and c-myc genes were detected except Wnt1.
Conclusion: The activation of Wnt/beta-catenin signaling transduction pathway might be one of the reasons for rat hepatocarcinogenesis.