Inhibition of in vitro carcinogenicity by 8-bromo-7-methoxychrysin mediated by modulating miR-519d/TWIST1 axis in liver cancer stem-like cells from SMMC-7721 cell line / 中国药理学通报

ABSTRACT

Aim To determine whether 8-bromo-7-me-thoxychrysin ( BrMC) inhibits in vitro carcinogenicity via up-regulating miR-519d expression and down-regu-lating Twist1 expression in liver cancer stem-like cells ( LCSLCs) derived from SMMC-7721 cell line. Meth-ods The second generation spheroids derived from SMMC-7721 cell line were obtained by sphere-forming assay and were considered as LCSLCs . Then LCSLCs were treated with various concentrations ( 1.0, 3.0, 10.0 μmol·L-1) of BrMC. The expression level of miR-519d was detected using real-time PCR. And in vitro carcinogenicity was investigated by sphere-forming assay and clone-forming assay in agar. The transcrip-tional activity and protein expression of Twist1 were an-alyzed using luciferase reporter assay and Western blot. Moreover, the molecular mechanism of BrMC was elucidated via miR-519 mimic transfection and Twist1 gene transduction, respectively. Results Compared with SMMC-7721 cells, miR-519d-3p was low-ex-pressed and Twist1 was over expressed in LCSLCs. And the sphere-forming ratio and the clone-forming ra-tio decreased by treatment with BrMC ( 1.0, 3.0, 10.0 μmol·L-1) in a dose-dependent manner. Fur-thermore, luciferase reporter assay demonstrated miR-519d could directly target the 3′ untranslated region of Twist1 mRNA and regulate protein expression. miR-519d mimic enhanced the effects of BrMC (3.0 μmol ·L-1) . However, Twist1 gene transduction effective-ly reversed the effects of BrMC ( 3.0 μmol·L-1) . Conclusion BrMC inhibits in vivo carcinogenicity via regulating miR-519/Twist1 signal axis in LCSLCs de-rived from SMMC-7721 cell line.