Studies On The Correlation Between Adenylate Cyclase-Associated Protein 1 And Hepatocellular Carcinoma

Objective1. To investigate the expression of CAP1 in the hepatocellular carcinoma (HCC), and analyze the correlation of CAP1 expression and the development and prognosis of HCC patients.2. To investigate the expression variation of CAP1 during the metastasis process of HCC, and investigate the role of CAP1 during the process. To futher broaden our understanding of the molecular mechanisms of HCC metastasis, and provide a novel target for therapy of HCC.Methods1. In tissue level, the expression of CAP1 in 8 paired HCC specimens and the adjacent liver tissues were detected by Western blot. The mRNA levels of CAP1 were examined in eight paired HCC specimens and adjacent non-cancerous liver tissues using Real-time PCR assay. Immunohistochemical staining was used to detect the expression of CAP1 in 107 samples of HCC tissues and adjacent non-tumor tissues. To evaluate the association of CAP1 and clinicopathological factors of HCC patients, such as age、 gender、histological grade、metastasis、tumor size and so on. One hundred and seven cases of HCC patients were followed up, survival curve was calculated by the Kaplan-Meier method, and the orognosis was analyzed by the univariate and multivariate Cox Droportional hazards regression analysis.2. In cell level, the expression of CAP1 was detected in normal lepatocyte cell line LO2 and four HCC cell lines:HuH7, HepG2, MHCC97H, BEL-7404. Immunofluorescence assay determined whether CAP1 and actin were colocalized in MHCC97H cells. After MHCC97H cells were transfected with CAP1-targeting siRNA, the migration of MHCC97H cells was detected by the wound healing and the transwell migration assay.Results1.In tissue level, immunohistochemistry, western blot and Real-time PCR assay showed that CAP1 expression in HCC were higher than that in adjacent non-cancerous liver tissues. The mRNA levels of CAP1 in metastatic HCC were significantly elevated compared with that in the primary HCC. CAP1 expression was correlated with tumor metastasis (P=0.002), The Kaplan-Meier survival curves displayed that high CAP1 expression related to a poor survival with statistical significance (p<0.01). Unvaried analysis showed that CAP1 expression was related with poor prognosis of HCC (p=0.000). Multivariate Cox proportional hazards regression analysis reveled that CAP1 expression was an independent prognostic factor for HCC (p= 0.010).2. In cell level, western blot showed that the expression of CAP1 in HCC cell lines was higher than normal hepatocyte cell line LO2, MHCC97H cell lines displayed highest abundance of CAP1 among these cell lines. CAP1 and F-actin were colocalized in the eading edge of the lamellipodium of MHCC97H cells by the immunofluorescence assay. After CAP1-targeting siRNA was transfected into MHCC97H cells, we found that interference of CAP1 displayed an evident inhibitory effect on MHCC97H cell notility.Conclusions1. The expression of CAP1 was up-regulated significantly in HCC, CAP1 may serves as an independent prognostic factor for HCC. These results revealed that CAP1 might play an important role in the development of HCC.2. During the the migration process of MHCC97H cells, the expression of CAP1 was up-regulated, CAP1 promotes the migration of MHCC97H cells, probably through modulating the assembly of actin cytoskeleton.