Cytochrome c cytc

A methylthiazolyldiphenyl-tetrazolium bromide (MTT) cell proliferation and cytotoxicity assay kit was purchased from Beyotime Biotechnology (Shanghai, China). Annexin-V fluorescein isothiocyanate (Annexin-V FITC) and propidium iodide (PI) apoptosis detection kits were purchased from Sigma-Aldrich Trading Co., Ltd. (Shanghai, China). Antibodies against β-actin, Bax, Bcl-2, cytochrome C (CytC), caspase-9, caspase-3, and PARP were purchased from Beyotime Biotechnology (Shanghai, China). Unless specifically stated, all other reagents were analytical grade.

Podophyllotoxin, MTT, propidium iodide (PI), Hoechst 33258 and Rodamine 123 were all purchased from Sigma-Aldrich (St. Louis, MO, USA). Hydroxycamptothecin (HCPT) was purchased from Harbin Shengtai Pharmaceutical Co., Ltd. (Harbin, China); RPMI 1640 culture medium was purchased from Thermo Fisher Scientific Inc. (Waltham, MA, USA); fetal bovine serum (FBS) was obtained from Hangzhou Sijiqing Biological Engineering Materials Co., Ltd. (Hangzhou, China) and trypsin was purchased from Gibco-BRL (Rockville, MD, USA). Additionally, mouse anti-human β-actin, cytochrome c (cyt-c), caspase-9 and caspase-3 polyclonal antibodies, alkaline phosphatase (AP)-conjugated goat anti mouse polyclonal antibody, SDS-PAGE sample loading buffer, blocking buffer, TBST, buffer5-bromo-4-chloro-3-indolyl-phosphate (BCIP)/nitroblue tetrazolium (NBT) alkaline phosphatase color development kit (Beyotime Institute of Biotechnology, Haimen, China); detergent-compatible protein assay kit (Bio-Rad, Hercules, CA, USA).