Publications (1)0 Total impact
[show abstract] [hide abstract]
ABSTRACT: ObjectiveTo investigate the influence of O-(4-ethoxyl-butyl)-berbamine (EBB) on the expression of cyclin B1 and cdc2-p34 in the human
drug-resistant breast cancer MCF-7/ADR cell line.
MethodsThe MTT assay was used to assess the cytotoxicity of EBB. Different levels of EBB were added to different cell lines at series
of time points solely or combined with doxorubicin (DOX) to detect the effect on the expression of cyclinB1 and cdc2-p34 by
Western blots. cdc2-p34 tyrosine phosphorylation was detected by immunoprecipitation. In addition, apoptosis and cytoplastic
Ca2+ concentrations were systematically examined by laser scanning confocal microscopy (LSCM).
ResultsEBB showed little inhibitory activity on human umbilical vein endothelial cells (ECV304), whereas EBB inhibited cell growth
(IC50 range, 4.55–15.74 μmol/L) in a variety of sensitive and drug-resistance cell lines. EBB also down-regulated the expression
of cyclin B1 and cdc2-p34 in a concentration and time dependent manner, which was an important reason for the G2/M phase arrest. EBB was shown to induce apoptosis of MCF-7/ADR cells while increasing the level of cytoplastic Ca2+.
ConclusionThe low cytotoxicity of EBB suggests it may be useful as a rational reversal agent. The effect of EBB on cell cycle arrest
and related proteins, apoptosis, and cytoplastic Ca2+ concentration may be involved in reversing multidrug resistance.