GIPC1 Promotes Proliferation,Migration And Invasion Of Hepatoma Cell And Its Molecular Mechanism

Background:Hepatocellular carcinoma(HCC)is one of the most common malignant tumors with high morbidity and mortality and poor prognosis.It is an important way to improve the prognosis of primary hepatocellular carcinoma(PHC)by studying the mechanism of its occurrence and development and finding new targets for early diagnosis and treatment of PHC.GIPC1 is an intracellular scaffold protein,which plays an important role in the transport and regulation of cell membrane receptors.Recent studies indicated that GIPC1 is a new tumor-associated antigen and a potential target for cancer therapy.However,the role of GIPC1 in the development of hepatoma and its molecular mechanism is still unclear.AIM:To investigate the role of GIPC1 in the development of hepatoma and its molecular mechanism.Methods:1)Immunohistochemistry was used to detect the expression of GIPC1 in different tissues of liver cancer tissue microarray;2)SMMC-7721 hepatoma cell models with GIPC1 shRNA knockdown and rescue Flag-GIPC1 overexpression were constructed;Cell counting,CCK-8,colony formation,scratch assay,transwell experiments and animal experiments were used to detect the proliferation,migration,invasion and tumor growth of GIPC1 on hepatoma cells,respectively.3)Western Blot and q-PCR were used to detect the expression of GIPC1-related signaling molecules and clarify its molecular mechanism.Results:1)The expression of GIPC1 in liver cirrhosis,primary liver cancer,paracancerous tissue and metastasis of liver cancer were higher than that in normal liver tissues,which indicated that the expression of GIPC1 was positively correlated with the occurrence and development of liver cancer.2)Compared with shControl group,the proliferation,migration and invasion of hepatoma cells were significantly inhibited after shGIPC1 knockdown,while the proliferation,migration and invasion of hepatoma cells significantly restored with the over-expression of Flag-GIPC1,indicating that GIPC1 significantly promoted the proliferation,migration and invasion of hepatoma cells.Animal experiments showed that GIPC1 could promote subcutaneous tumorigenesis and tumor growth of hepatoma cells in nude mice.3)It was found that the expression of PDGFR-?protein and mRNA in hepatoma cells decreased significantly after GIPC1 knockdown,and the phosphorylation levels of PI3K,AKT and mTOR also decreased significantly.On the contrary,the expression levels of PDGFR-? protein and mRNA increased significantly after Flag-GIPC1 overexpression,and the phosphorylation levels of PI3K,AKT and mTOR increased accordingly.Further studies showed that p300 and H3K27ac were also positively correlated with GIPC1 expression,suggesting that GIPC1 may up-regulate the expression of PDGFR-? through p300.It was also found that AKT inhibitors could significantly inhibit the proliferation and migration of hepatoma cells and reduce the phosphorylation level of AKT,while supplementation of PDGF-bb could promote the proliferation and migration of hepatoma cells and increase the phosphorylation level of AKT,suggesting that GIPC1 promotes the proliferation and migration of hepatoma cells depending on the activation of PI3K/AKT/mTOR signaling pathway mediated by PDGFR-?.Conclusions:GIPC1 is positively correlated with the occurrence and development of hepatoma.GIPC1 can significantly promote the proliferation,migration,invasion and tumor growth of hepatoma cells.Its molecular mechanism may be as follows:GIPC1 upregulates PDGFR-? through enhancement of transcription induced by 300 increation.The promotion of proliferation,migration of GIPC1 mediated by PDGFR-? depends on the activation of PI3K/AKT/mTOR signaling pathway.This study explored the correlation between GIPC1 and the occurrence and development of hepatoma,clarified the role of GIPC1 in promoting the proliferation,migration and invasion of hepatoma cells and the growth of transplanted tumors in nude mice,and preliminarily clarified its molecular regulatory mechanism.The study also discussed the feasibility of GIPC1 as a new target for the treatment of hepatoma,providing a new basis and theoretical basis for targeted therapy of tumors based on GIPC1 target.