Thiazole Antibiotics Target FoxM1 and Induce Apoptosis in Human Cancer Cells (original) (raw)
Figure 3
Overexpression of FoxM1 partially protects cancer cell lines from thiazole antibiotic-induced apoptosis.
(A) Immunoblot analysis after treatment with Siomycin A revealed close correlation between downregulation of FoxM1 and induction of apoptosis. (B) Following treatment with thiostrepton, thiopeptide-induced apoptosis and inhibition of FoxM1 protein expression are more prominent in the presence of cyclohexamide (Chx) as depicted by immunoblotting for FoxM1 and cleaved caspase-3. (C) The expression of endogenous FoxM1 decreased in a time-dependent fashion in the presence of thiostrepton and Chx, while the levels of exogenous FoxM1 were not affected. Overexpression of FoxM1 protected against cell death induced by thiostrepton as detected by immunoblotting for cleaved caspase-3. (D) FoxM1 overexpressing cells were resistant to the treatment with increasing amount of Siomycin A as analyzed by immunoblotting for cleaved caspase-3. (E) Immunoblot analysis revealed that overexpression of FoxM1 also protected against Siomycin A-induced apoptosis in the presence of Chx.