RAF1 and hepatocellular carcinoma: To explain these findings, Huitzil-Melendez et al postulates that there may be significant differential expression of Raf-1, an important kinase involved in the oncogenesis of HCC, among HCV- and HBV-related HCC, given that HCV core proteins are known to induce a high basal rate of Raf-1 activity (50, 51).