MAPK3 and hepatocellular carcinoma: Previous studies have shown that upregulation of caprin-1 expression is associated with poor prognosis in patients with HCC [30], and that the protein regulates the proliferation and invasion of human breast cancer cells [36], as well as promotes osteosarcoma tumor growth and lung metastasis in mice by activating the Akt and Erk1 pathways [32].