HSP90 Inhibitor 17-AAG Inhibits Migration And Invasion Of Anaplastic Thyroid Carcinoma By Down-regulating HIF-1?

Objective: To study the effect of heat shock protein 90(Heat-Shock Proteins 90)inhibitor 17-propylene amino-demethoxy-geldanamycin(17-AAG)on invasion and metastasis of anaplastic thyroid carcinoma(ATC).To explore the molecular mechanism of HSP90 and hypoxia-inducible factor-1?(HIF-1?)and its downstream invasion-related proteins in ATC cells.Methods: The effect of 17-AAG(0,250,500,1000,2000,4000 nM)on the survival of anaplastic thyroid carcinoma(ATC)cell lines 8305 c and 8505 c was detected by the cell counting kit method at 12 h,24h,48 h,respectively.Test the effect of 17-AAG on ATC cell metastasis and invasion ability by Transwell chamber experiment.Western blotting was used to detect the effects of HIF-1? and the expression levels of invasion-related proteins MMP2,VEGF,and E-cadherin.The potential mechanism of HSP90 and HIF-1? was evaluated by immunoprecipitation experiments.The plasmid was transfected into anaplastic thyroid carcinoma cell lines 8503 c and 8505 c by Lipofectamine 2000 method.The changes of ATC cell invasion and metastasis after17-AAG treatment were observed,and the expression levels of related proteins were further detected by Western blot.Results: With the increase of 17-AAG concentration,the activity of ATC cells was inhibited(P < 0.05),and the activity of ATC cells was also inhibited with the prolongation of the action time(P < 0.05).The results of Transwell chamber experiments and cell scratch experiments suggest that 17-AAG can inhibit the invasion and metastasis of ATC cells.Western blot analysis showed that the expression of HIF-1 ?,MMP2 and VEGF was inhibited by 17-AAG(P < 0.05),while the expression of E-cadherin protein was increased.HIF-1? was confirmed to be a client protein of HSP90 by immunoprecipitation experiments.Overexpression of HIF-1 ?protein restored the metastatic and invasive ability of the ATC cell line in ATC cells treated with 17-AAG.Conclusion: Our results indicate that 17-AAG inhibits cell metastasis and invasion in ATC cell lines by disrupting the stability of HSP90 and HIF-1?,thereby down-regulating the expression of HIF-1? protein in ATC cells,and thendown-regulating expression of MMP2,VEGF,thereby inhibiting ATC cell migration and invasion.