| Objective: To investigate the effect of copper on the development and Wnt signaling pathway of colorectal cancer liver metastasis,and to explore the mechanism of copper on colorectal cancer liver metastasis from molecular biology perspective by establishing a BALB/c mouse liver metastasis model of colorectal cancer.Methods: The liver metastasis model of colorectal cancer was established by spleen injection with splenectomy.48 male BALB/c mice were randomly divided into 4 groups according to body weight,12 in each group.They were control group,copper group(0.3mg/kg),tetrathiomolybdate(TM)group(1mg),and copper + TM group(0.3mg/kg + 1mg).Gavage was used for 1 week in advance.Second days after operation,the same gastric lavage was given.At the same time,TM group and copper +TM group were treated with 1mg TM,and the mice were killed for about 4 weeks,and the number of nodules and liver metastasis were observed.The expression of Wnt pathway related factors glycogen synthase kinase-3β(GSK-3β)andβ-chain protein(β-catenin)at the level of translation and phosphorylation were detected by Western-blot.RT-PCR and immunohistochemistry were used to detect downstream metastasis related factors of Wnt pathway: E-cadherin、matrix metalloproteinase-7、-9(MMP7、MMP9)、 adhesion molecules(CD44)、vascular endothelial growth factor(VEGF)m RNA and protein expression changes.Results: There was no significant difference in weight change during the experiment of mice in each group(P > 0.05).Compared with the control group and the copper + TM group,the number of nodules increased significantly in copper group(P < 0.05),and there was a significant difference between the control group and the TM group(P < 0.05).The rate of liver metastasis in the copper group was higher than that of the other three groups,suggesting that copper could promote the metastasis of colorectal cancer to a certain extent.The expression of p GSK3βandβ-catenin protein in the copper group was significantly higher than that in the control group and the copper +TM group,and the difference was statistically significant(P < 0.05).Copper also significantly increased MMP7、MMP9、CD44、VEGF protein and m RNA expression(P < 0.05),and reduced E-cadherin protein and m RNA expression in the downstream of Wnt pathway(P < 0.05).Conclusion: Copper can promote the occurrence of colorectal cancer liver metastases,and its mechanism involves transcription,translation and phosphorylation of related factors in the Wnt/β-catenin signaling pathway.Copper can inhibit GSK-3β activity,reduce the degradation of downstream β-catenin,thereby promoting β-catenin translocate into the nucleus,causing changes in the expression of downstream target genes E-cadherin、MMP7、MMP9、CD44、VEGF,to achieve the promotion of liver metastasis of colorectal cancer,and promoting the development process of colorectal cancer. |
PDF Full Text Request