Journal: The Journal of Clinical Investigation
Article Title: Hsp90B enhances MAST1-mediated cisplatin resistance by protecting MAST1 from proteosomal degradation
Figure Lengend Snippet: Inhibition of hsp90B sensitizes cisplatin-resistant cancer cells to cisplatin through MAST1. ( A ) Cisplatin IC 50 upon 17-AAG treatment (50 nM, 48 hours) with or without MAST1 knockdown. Cisplatin IC 50 values were determined by CellTiter-Glo assay and analyzed by GraphPad Prism 8. ( B ) Effect of 17-AAG and MAST1 knockdown on tumor growth of cisplatin-treated xenograft mice. Mice were treated with cisplatin (5 mg/kg) and 17-AAG (50 mg/kg) from 5 days after xenograft. Tumor volume (left) and tumor weight (right) for each group and MAST1 expression in tumor lysates are shown. Cisplatin IC 50 ( C ) and cisplatin-resistant tumor growth ( D ) upon 17-AAG treatment, MAST1 knockdown, and rescue expression of MAST1 WT. Cell viability assay and xenograft assay were performed as in A and B . ( E ) Cell proliferation of KB-3-1 cisR and A549 cisR cells with hsp90B knockdown and MAST1 overexpression in the presence of cisplatin. Cells were treated with sublethal doses of cisplatin (5 μg/mL KB-3-1 cisR ; 2 μg/mL A549 cisR ) and proliferation was determined by trypan blue exclusion. ( F ) Effect of hsp90B knockdown and MAST1 overexpression on cisplatin-resistant tumor growth. Mice were treated with cisplatin (5 mg/kg) from 5 days after xenograft. Tumor volume (left) and tumor weight (right) for each group and hsp90B and MAST1 expression in tumor lysates are shown. Data shown are representative of 2 ( A – D and F ) and 3 ( E ) independent biological experiments. Data are mean ± SD from 3 technical replicates for A , C , and E ; n = 6 for B , D , and F . Error bars represent SEM for tumor volume and SD for tumor weight. Statistical analysis was performed by 2-way ANOVA for B , D , and F (left), and E , and 1-way ANOVA for A and C and B , D , and F (right). * P
Article Snippet: The CHIP H260Q mutant, MAST1 variants including K317R, K545R, K317R/K545R (2KR), D497A, and CHIP or MAST1 shRNA resistant silent mutants were generated using site-directed mutagenesis kit (Agilent Technologies).
Techniques: Inhibition, Glo Assay, Mouse Assay, Expressing, Viability Assay, Xenograft Assay, Over Expression