Dynactin 2 acts as an oncogene in hepatocellular carcinoma through promoting cell cycle progression

Background: Dynactin (DCTN) can activate cytoplasmic dynein and drive intracellular organelle transport containing six family members (DCTN1 to DCTN6). The DCTN family has been studied as cancer-related genes or biomarkers in various cancers. Nevertheless, in hepatocellular carcinoma (HCC), the functions and prognostic roles of the DCTN family have been unexplored. Methods: We evaluated the diagnostic and survival effects of DCTN subunits in HCC through bioinformatics analysis and validated the results of bioinformatics by our data to address this problem. Results: The results of bioinformatics analysis found that DCTN2 was a significant prognostic factor in HCC, and high-level DCTN2 can predict poor patient survival in HCC. Cox regression analysis also suggested that DCTN2 (hazard ratio = 1.748, 95% confidence interval 1.190–2.568, P = 0.004) is an independent prognostic factor for patient survival. Western blot and quantitative reverse transcription-polymerase chain reaction assays confirmed that the protein and mRNA expression levels of DCTN2 were upregulated in HCC cell lines. The proliferation, invasion, and migration were decreased and cell apoptosis was enhanced after DCTN2 was knocked down in Huh7 and Hep3B cells. DCTN2 promoted the cell cycle progression through regulating the expression of cell cycle regulatory proteins cyclin-dependent kinase 4, Cyclin D1, and p21. Conclusions: We propose that DCTN2 can serve as a prognostic marker for HCC. DCTN2 acts as an oncogene and promotes the cell cycle progression through the G1/S phase-related signaling pathway.