Objective   To investigate the effect of the nuclear factor-κB (NF-κB) inhibitor

pyrrolidine dithiocarbamate (PDTC) and paclitaxel on the proliferation and invasion of human breast cancer cell line MDA-MB-231.    Methods   The MDA-MB-231 cells were treated with PDTC (100 μmol/L) or paclitaxel (1 μmol/L)

or combined treatment. The effect of proliferation was analyzed by MTT assay. The cell cycle was evaluated by flow cytometry. RT-PCR was used to detect the expression of NF-κB p65 mRNA. Western blotting were used to determing the expression of NF-κB p65

MMP-9 and TIMP-1 i

n MDA-MB-231 cells after treatment. The invasion ability of MDA-MB-231 cells was tested ty the invasion

migration and cell adhesion assay.    Results   The cell growth was significantly slowed down and the cell cycle was arrested at G

0

/G

1

phase after combined treatment. The expression of NF-κB p65 and MMP-9 was downregulated (P0.05) compared with paclitaxel treatment group

and the invasion ability of MDA-MB-231 cells was decreased after combined treatment (P0.01).    Conclusion   PDTC combined with paclitaxel effectively inhibits cell proliferation

induces cell cycle arrest

and decreases cell invasion ability of human breast cancer MDA-MB-231 cells. Its mechanism may be associated with PDTC inhibiting the NF-κB-related gene expression.