Figure 5.

miR-29a enhances HCC tumor growth and metastasis in vivo by inhibiting the TET–SOCS1–MMP9 signaling pathway. (a) miR-29a overexpression promoted tumor growth in orthotopic SMMC-7721 cells implantation mouse models, whereas miR-29a inhibited caused the opposite result (left). Tumor volumes at week 6 were quantitated (right). (b) Metastatic lesions in the lungs of mice at week 6 (left), the total numbers and grades of lung metastatic lesions in the different groups of nude mice were measured (right). Data are shown as mean±S.D. (n=3). *P<0.05, **P<0.01, and ***P<0.001. (c) In SMMC-7721 and HepG2 cells transfected with miR-29a vector, expression levels of p-Stat3, p-ERK1/2, and MMP9 were significantly increased compared with control cells. While miR-29a inhibited caused the opposite result. TET1, 2, and 3 knockdown in HCCLM3-anti-miR-29a cells promoted p-Stat3, p-ERK1/2, and MMP9 expressions. DNMT1 and DNMT3A knockdown in HCCLM3-anti-miR-29a cells, which had no significant effect on SOCS1, p-Stat3, p-ERK1/2, and MMP9 expressions, downregulation DNMT3B slightly decreased p-Stat3 and p-ERK1/2 expressions. (d and e) IHC staining for TET–SOCS1–MMP9 pathway-related proteins in tumor tissues from orthotopic HCC implantation mice. Scale bars=100 μm. (f) ChIP-PCR assays demonstrated the binding of TET1 to the SOCS1 promoter in HCC cells