Since Rho-mediated signaling can regulate liver cancer cell proliferation, amino acid sequence changes of its downstream targets, actins, might alter the properties of cell growth. Here, we investigated the function of a novel class of actins, named κ-actins, in hepatocellular carcinoma (HCC).
Materials and methods: Alexander cells overexpressing an HCC-derived κ-actin (Alex-κ cells) were established to study growth property changes. κ-actin expression was also determined in tumor and noncancerous tissues from 72 HCC patients. Survival analysis was conducted to evaluate the prognostic predictive value of κ-actin expression.
Results: Phylogenetic analysis showed that κ-actin sequences constituted 94.7% and 17.6% of actin transcripts in Alex-κ and naive Alexander cells, respectively. Alex-κ cells exhibited serum-independent cell growth with increased anchorage-independent colony formation and BrdU incorporation upon serum deprivation. Cox proportional hazard analysis showed that κ-actin expression in both cancerous and noncancerous tissues predicted poorer postoperative disease-free survival (p=0.004).
Conclusion: Overexpression of κ-actin altered growth properties of hepatoma cells, contributing to poor postoperative prognosis.