Research Paper Volume 13, Issue 6 pp 8380—8395

Figure 4. Extracellular HMGB1 promotes CD44 expression through miR-21 mediated activation of OCT4/ TGF-β1 signaling. (A, B) Immunoblot analysis shows that miR-21 inhibitor restricts OCT4 expression and nuclear translocation caused by rhHMGB1. HepG2 and HCCLM3 cells were transfected with negative control, OCT4 siRNA or miR-21 inhibitor and then cultured with rhHMGB1 (1μg/ml) for 24h. (C) Q-PCR analysis indicates miR-21 inhibitor represses TGF-β1 expression caused by rhHMGB1. HepG2 and HCCLM3 cells were transfected with negative control or miR-21 inhibitor and then cultured with rhHMGB1 (1μg/ml) for 24h. (D) Supernatant TGF-β1 is measured by ELISA assays and results indicate that miR-21 inhibitor and OCT4 siRNA both suppresses TGF-β1 secretion caused by rhHMGB1. HepG2 and HCCLM3 cells were transfected with negative control, OCT4 siRNA or miR-21 inhibitor and then cultured with rhHMGB1 (1μg/ml) for 24h. (E) Immunoblot analysis shows that miR-21 inhibitor and TGF-β1 antibody both suppress CD44 expression by inactivating TGF-β1/Smad signaling. HepG2 and HCCLM3 cells were treated with negative control, TGF-β1 antibody or miR-21 inhibitor and then cultured with rhHMGB1 (1μg/ml) for 24h. Data are means ± SEM, * means p<0.05, ** means p<0.01, *** means p<0.001 by unpaired student T test.