Fig. 4

Downregulation of USP37 weakens cell self-renewal and chemo-resistance to cisplatin. a, b MCF-7 and MDA-MB-231 cells were transfected with shUSP37#2 and shScramble, and expressions of USP37, Smo, Gli-1, ALDH1 and OCT4 were confirmed by western blotting. *P < 0.05, **P < 0.01. c, d Comparison of mammosphere formation among inoculated cells in MCF-7 and MDA-MB-231 cells (original magnification, 4× or 20×).*P < 0.05, ***P < 0.001. e MCF-7-ShScramble and MCF-7-shUSP37#2 cells were treated with cisplatin (1 μg/ml) for 48 h, then treated cells were harvested to detect the levels of Bcl-2, Bax and cleaved caspase 9. GAPDH was examined as a loading control. j MDA-MB-231 cells transfected with shScramble or shUSP37#2 were exposed to 3 μg/ml cisplatin for 48 h, and the levels of Bcl-2, Bax and cleaved caspase 9 were detected via western blotting. f, g, k, l CCK-8 assay and colony formation assay showed that cell viability was decreased in MCF-7 and MDA-MB-231 cells after USP37 knockdown. Quantitation of colony formation in (h) MCF-7 and (i) MDA-MB-231. GAPDH was examined as a loading control. *P < 0.05, **P < 0.01, ***P < 0.001