Study of mechanism of indirubin derivative PHⅡ-7 in augmenting TRAIL-induced cytotoxicity in breast cancer cell line as well as its chemo-resistant counterpart / 中国药理学通报

ABSTRACT

Aim To investigate the effect of indirubin derivative PHⅡ-7 and TRAIL on proliferation in breast cancer cell MCF-7 and its MDR counterpart MCF-7/ADR and the mechanism.Methods Growth inhibition rate was examined respectively by MTT assay under treatment with TRAIL or PHⅡ-7 or in combination. Cell apoptosis and ROS production were examined by flow cytometry.The change of TRAIL receptors(DR4/DR5 )in mRNA was analysed by realtime PCR.Re-sults IC50 of PHⅡ-7 on MCF-7 and MCF-7/ADR was (4.49 ±1.55 ),(3.44 ±0.90 )μmol · L-1 respec-tively;MDA-MB-231 was TRAIL sensitive cell line, and apparently TRAIL induced apoptosis in MDA-MB-23 1 .Low concentration of PHⅡ-7 in combination with TRAIL could augment TRAIL-induced cytotoxic effect including apoptosis while TRAIL or PHⅡ-7 treatment alone had limited cytotoxity to those cells.Besides, PHⅡ-7 at this concentration had little toxicity to hu-man peripheral blood mononuclear cells even if in com-bination with TRAIL.PHⅡ-7 generated ROS produc-tion inside MCF-7 and MCF-7/ADR cells and up-regu-lated DR4/DR5 expression concentration dependently. Once upon ROS scavenger NAC involved,the effect of TRAIL receptors up-regualtion by expression was abro-gated.Conclusions PHⅡ-7 at low concentration could improve the sensitivities of breast cancer cell MCF-7 and MCF-7/ADR to TRAIL,the mechanism of which may be the ability of ROS production by PHⅡ-7 help up-regulated TRAIL receptor DR4,DR5 .Our re-search set a solid foundation for PHⅡ-7 in combination with TRAIL in future clinical application.