[Effect of calmodulin antagonist O-4-ethoxyl- butyl-berbamine on the proliferation of human breast cancer cell line MCF-7 and its relevant mechanism].

OBJECTIVE: To investigate the effect of calmodulin antagonist O-(4-ethoxyl-butyl)-berbamine (EBB) on proliferation of human breast cancer cell MCF-7 and its possible mechanism. METHODS: MTT assay was used to analyze the effect of EBB on tumor cells growth. Flow cytometry was used to detect its impact on the cell cycle of MCF-7 cells. Immunofluoresce labeling technique and laser scanning confocal microscope were used to reveal the changes of the microtubule, microfilament, mitochondrion, and endoplasmic reticulum in the cells. RESULTS: The IC50 value of EBB in MCF-7 cells was (13.0 +/- 3.7) micromol/L. MCF-7 cells were arrested at S phase after EBB treatment. Meanwhile, depolymerization of the microtubule and microfilament, impairment of the mitochondrion and swelling of endoplasmic reticulum were observed. CONCLUSION: EBB arrests MCF-7 cells at S phase by inhibiting the growth of MCF-7 cells, which may be related to the changes of structures and functions of the microtubule, microfilament, mitochondrion, and endoplasmic reticulum.