Carfilzomib inhibits the progression of hepatocellular cancer by upregulating GADD45α expression

Hepatocellular carcinoma (HCC) ranks among the most prevalent and lethal cancers affecting humans. Currently, there are limited effective treatments available for HCC. Carfilzomib, a proteasome inhibitor, is known to exert anti-HCC activities; however, its underlying mechanisms of action remain unclear. In the present study, the efficacy of carfilzomib against HCC was evaluated and its underlying mechanisms were explored. Cell Counting Kit-8, 5-ethynyl-2-deoxyuridine staining and colony formation assays were employed to analyze the antiproliferative effect of carfilzomib on MHCC-97H and Huh7 cells. Additionally, flow cytometry was used to assess the effect of carfilzomib on the cell cycle and Transwell assays were used to evaluate the effect of carfilzomib on cell migration and invasion. Western blotting was utilized to examine the protein expression levels associated with cell cycle arrest. Furthermore, short hairpin RNA (shRNA) transfection was used to investigate the role of DNA damage inducible α (GADD45α) on carfilzomib-induced cell cycle arrest. A xenograft tumor model using nude mice was employed to evaluate the anti-HCC activity of carfilzomib <i>in vivo</i>. The findings demonstrated that carfilzomib inhibited proliferation, invasion and migration in both MHCC-97H and Huh7 cells. In addition, carfilzomib caused cell cycle arrest by suppressing the expression of cyclin A2, cyclin E1 and cyclin-dependent kinases 2 and 4. Carfilzomib also upregulated the expression of GADD45α, activated the MAPK pathway and inhibited GADD45α through shRNA abolished carfilzomib-induced cell cycle arrest in HCC cells. In addition, carfilzomib inhibited Huh7 cell growth <i>in vivo</i>. To conclude, the present research revealed that carfilzomib inhibits the progression of HCC cells by upregulating GADD45α expression, suggesting that carfilzomib could be a potential chemotherapeutic agent against HCC.