Abstract: Objective To investigate the effects of emodin-8-O-β-D-glucoside (EG) combined with paclitaxel (PTX) on the viability and metastasis of human breast cancer cells. Methods MTT assay was used to detect the cell viability of EG, PTX alone and concomitant administration on MCF 7 and MDA-MB-231 cells, and the combination index (CI) value was calculated to evaluate the effects of the two drugs; Transwell assay was used to detect the metastasis ability of the two drugs combinations on two kinds of breast cancer cells; The mRNA expression level of metastasis-associated genes (MMP2、MMP9, CDH1, CDH2, Vimentin and Snail) detected by Quantitative Real-time PCR. Results EG and PTX significantly inhibit the survival of human breast cancer MCF 7 and MDA-MB-231 cells (P<0.01), and the two drugs exhibited a synergistic effect at experimental concentrations; The combination of EG (240 mmol·L^-1) and PTX (5 nmol·L^-1) can substantially suppress the metastasis of human breast cancer cells (P< 0.01); the expressions of matrix metalloproteinase genes MMP-2 and MMP-9 (P<0.01), EMT-related genes Vimentin (P<0.01) and Snail (P<0.01, P<0.05) in breast cancer cells was significantly down-regulated through the combination of two drugs; the combination can up-regulated the expression level of CDH1 in MCF 7 cells and down-regulated the expression level of CDH2 in MDA-MB-231 cells (P<0.01). Conclusion EG combined with PTX can synergistically inhibit the viability and metastasis of human breast cancer cells.

Key words: emodin-8-O-β-D-glucopyranoside, paclitaxel, combination of drugs, human breast cancer cell, metastasis, matrix metalloproteinases (MMPs), epithelial-mesenchymal transition (EMT)