MiR-744 suppresses the proliferation and chemoresistance of HCC. (A) HepG2 cells were transfected with the miR-744 mimic or co-transfected with miR-744 and PAX2. An EdU labeling assay was utilized to show the impact of miR-744 on cell proliferation (* compared with miR-NC, # compared with miR-744, ns: no significant difference compared with miR-NC). (B) The effect of the indicated transfection on the sorafenib resistance of HepG2 cells; CCK-8 assay was performed to assess cell viability 24 hours after sorafenib treatment (* compared with miR-NC, # compared with miR-744, ns: no significant difference compared with miR-NC). (C) CCK-8 assay shows the sorafenib-resistant ability of the established HepG2-R cells and normal HepG2 cells. (D) Western blotting shows the exosome protein markers of the isolated exosomes derived from HepG2 and HepG2-R cell culture media. (E) The exosomal miR-744 levels in HepG2 and HepG2-R cell culture media were evaluated by qRT-PCR. * and # represent P<0.05, ** and ## represent P<0.01, and *** P<0.001. HCC – hepatocellular carcinoma; EdU – 5-ethynyl-2′-deoxyuridine; CCK-8 – Cell Counting Kit-8; qRT-PCR – quantitative real-time polymerase chain reaction.