Study on relationship between IGFBP-5/p53 axis and anti-proliferation effect of tetrandrine in MCF-7 cells / 中国药理学通报

Aim To study the effect of tetrandrine ( Tet ) on proliferation of MCF-7 breast cancer cells and the possible mechanism underlying this biological process. Methods CCK-8, flow cytometric and Western blot were introduced to analyze the effect of Tet on proliferation and apoptosis in MCF-7 cells.Re-al-time PCR and/or Western blot assay were employed to detect the effect of Tet on expression of IGFBP-5 , p53 and MDM2.CCK-8 and recombinant adenovirus were utilized to determine the effect of IGFBP-5 on the proliferation inhibitory effect of Tet .Western blot assay was introduced to evaluate the effect of IGFBP-5 on p53 which was induced by Tet .Results Tet inhibited the proliferation , arrested cell cycle at G 1 phase and decreased the expression of PCNA concentration dependently in MCF-7 cells.Meanwhile, Tet increased the percentage of apoptotic cells , the level of Bad and reduced the level of Bcl-2.Tet increased the expres-sion of IGFBP-5 either mRNA or protein , over-expres-sion of IGFBP-5 enhanced the anti-proliferation activity of Tet in MCF-7 cells, but knockdown of IGFBP-5 at-tenuated this effect of Tet .Tet increased the level of p53 and decreased that of MDM2, and exogenous IG-FBP-5 enhanced the effect of Tet on p53 and MDM2, respectively .Conclusion Tet can inhibit the prolifer-ation of MCF-7 cells, and this activity is partly media-ted by increasing the function of p 53 signal , which may be triggered by the Tet-induced IGFBP-5.

Influence of Expression Plasmid of Connective Tissue Growth Factor and Tissue Inhibitor of Metalloproteinase-1 shRNA on Hepatic Precancerous Fibrosis in Rats.

BACKGROUND: In this study, influence caused by expression plasmids of connective tissue growth factor (CTGF) and tissue inhibitor of metalloproteinase-1 (TIMP-1) short hairpin RNA (shRNA) on mRNA expression of CTGF,TIMP-1,procol-α1 and PCIII in hepatic tissue with hepatic fibrosis, a precancerous condition, in rats is analyzed. MATERIALS AND METHODS: To screen and construct shRNA expression plasimid which effectively interferes RNA targets of CTGF and TIMP-1 in rats. 50 cleaning Wistar male rats are allocated randomly at 5 different groups after precancerous fibrosis models and then injection of shRNA expression plasimids. Plasmid psiRNA-GFP-Com (CTGF and TIMP-1 included), psiRNA-GFP-CTGF, psiRNA-GFP-TIMP-1 and psiRNA- DUO-GFPzeo of blank plasmid are injected at group A, B, C and D, respectively, and as model control group that none plasimid is injected at group E. In 2 weeks after last injection, to hepatic tissue at different groups, protein expression of CTGF, TIMP-1, procol-α1and PC III is tested by immunohistochemical method and,mRNA expression of CTGF,TIMP-1,procol-α1 and PCIII is measured by real-time PCR. One-way ANOVA is used to comparison between-groups. RESULTS: Compared with model group, there is no obvious difference of mRNA expression among CTGF,TIMP-1,procol-α1,PC III and of protein expression among CTGF, TIMP-1, procol-α1, PC III in hepatic tissue at group injected with blank plasmid. Expression quantity of mRNA of CTGF, TIMP-1, procol-α1 and PCIII at group A, B and C decreases, protein expression of CTGF, TIMP-1, procol-α1, PC III in hepatic tissue is lower, where the inhibition of combination RNA interference group (group A) on procol-α1 mRNA transcription and procol-α1 protein expression is superior to that of single interference group (group B and C) (P<0.01 or P<0.05). CONCLUSIONS: RNA interference on CTGF and/or TIMP-1 is obviously a inhibiting factor for mRNA and protein expression of CTGF, TIMP-1, procol-α1 and PCIII. Combination RNA interference on genes of CTGF and TIMP-1 is superior to that of single RNA interference, and this could be a contribution for prevention of precancerous condition.