Differential Expression Of Wnt-1and Axin-1in Chemically Induced Liver Carcinogenesis In Mice

Objective To detect the expression of Wnt-1and Axin-1during theprocess of liver cancer in C57BL/6J mouse induced by chemicals, and to revealthe relationship between Wnt/β-catenin signaling pathway and liver cancer.Methods Ninety-five C57BL/6J male mice were divided randomly intothe experimental group (n=50) and the control group(n=45). Mice in theexperimental group were treated with diethylnitrosamine(DEN), carbontetrachloride (CCl4) and ethanol for twenty weeks to induce hepatocellularcarcinoma(HCC). Mice in the control group were not given any special treatment.Two groups of animals were fed mouse feed pellets and drank sterilized ordinarywater. Observe the growth, weight, mental, and appetite of the two groups miceduring the experiment. Five mice of each group were sacrificed every two weeksfrom the4th week and their liver specimens were collected. The expression ofWnt-signaling upstream factors Wnt-1and Axin-1were dynamically observed by Real-time PCR, Western Blot and immunohistochemistry, while thepathological changes were observed using HE staining.Results Liver cancer in C57BL/6J mice was successfully inducedchemically after20weeks. The results of Real-time PCR showed that theexpression of Wnt-1mRNA in the experimental group significantly increasedcompared to the control group at various time points during the period fromweeks14to20, while there was no significant difference from weeks4to12. Inthe experimental group, Wnt-1mRNA expression increased with time fromweeks14to16and18, and the mRNA levels were4.192±0.322,5.630±0.579and8.060±0.795(P<0.05), but there was no significant difference between weeks18and20(8.060±0.795vs8.038±0.649, P>0.05). Western Blot showed thatWnt-1protein expression was weak in the experimental group from weeks4to12, as with in the control group, but increased with time in the experimentalgroup, although there was also no significant difference between weeks18and20. Immunohistochemistry showed that Wnt-1was expressed weakly in theexperimental group at week8and the control group. but began to increase fromweek16in the experimental group, peaking at week20. The results of Real-timePCR and Western Blot showed that the expression of Axin-1in the experimentalgroup were reduced significantly compared to the control group during theperiod between16th and20th week(P＜0.05), and weakened as time progressed:the mRNA levels at the16th,18th and20th week were0.421±0.083,0.278±0.042and0.120±0.028respectively(P＜0.05). The results of immunohistochemistryshowed that the expression of Axin-1was positive in each time point in thecontrol group, while in the experimental group it began to reduce at the16thweek compared to the control group and was nearly negative at the20th week. Conclusion Wnt/β-catenin signaling pathway upstream factors Wnt-1and Axin-1may be associated with the development of HCC, and it reveals thatWnt/β-catenin signaling pathway may have a certain relationship with HCC.