Resumen
Protein canopy homolog 2 (CNPY2) controls the outgrowth of neurites through positive regulation of their outgrowth in neuroblastoma and pheochromocytoma due to stabilizing the myosin regulatory light chain (MRLC). Given the important role in endoplasmic reticulum (ER) stress and proteolysis, we focused on investigation of CNPY2 expression in mouse and human hepatocarcinogenesis and its clinical relevance in virus-associated liver cancer. CNPY2 elevation and coordinated accumulation of numerous cytoskeletal proteins and those involved in ER and mitochondrial stresses was found in mouse altered foci and tumors by proteome analysis of microdissected lesions. In Huh7 and HepG2 human liver cancer cells, CNPY2 increase was significantly associated with cell cycle progression, activated cell proliferation and invasion. CNPY2 expression was high in HCV-associated HCC patients, being positively associated with survival. To the best of our knowledge, this is the first report to demonstrate that CNPY2 may become a useful prognostic biomarker in HCV-associated HCC.