CCN1 and hepatocellular carcinoma: Another group of matricellular proteins involved in HCC is cellular communication network factors (CCN), core regulatory proteins—including cysteine-rich angiogenic protein 61 (CYR61 or CCN1), connective tissue growth factor (CTGF or CCN2), nephroblastoma overexpressed (NOV or CCN3) and Wnt1-Inducible Signaling pathway proteins (WISP-1 or CCN4)—that modulate cell–matrix interactions to modify the cellular phenotype.