C -reactive protein promotes tumor progression in Hepatocellular Carcinom by 1 interacting with Ephrin type B receptor 3

C-reactive protein (CRP), an acute phase protein, has been increasingly implicated in various tumors, and the role of CRP is positively correlated with invasion and metastasis in hepatocellular carcinoma cells. However, the mechanism of CRP affecting HCC progression remains poorly investigated. The present study investigated the role of CRP in HCC and the underlying mechanisms. We first found that CRP was significantly upregulated in HCC tissues and HCC cells, the expression level correlated with the metastatic ability of HCC cells. Knockdown of CRP significantly suppresses migration and invasion capacity in HCC cells. Through a proteomic analysis of CRP co-immunoprecipitation complexes, the Eph receptor B3 was identified as a new CRP interactor. Then we found that the expression and functions of EphB3 were consistent with CRP in HCC. In addition, co-immunoprecipitation and immunofluorescence assays suggested that EphB3 was able to interact with MAPK/ERK to activate MAPK/ERK signaling pathways. Furthermore, we showed that CRP can induce the phosphorylation of MAPK/ERK by binding EphB3. Our findings showed that CRP increased HCC cells migration and invasion by binding EphB3 to activate MAPK/ERK signaling pathways. It suggested that CRP may become a prognostic factor and a potential therapeutic target for liver cancer.