Wortmannin reduces metastasis and angiogenesis of human breast cancer cells via nuclear factor-κB-dependent matrix metalloproteinase-9 and interleukin-8 pathways.

OBJECTIVE

To investigate whether inhibition of Akt phosphorylation by the phosphatidylinositol 3-kinase (PI3K) inhibitor, wortmannin, reduces metastasis and angiogenesis in a human breast cancer cell line via nuclear factor (NF)-κB-dependent matrix metalloproteinase (MMP)-9 and interleukin (IL)-8 pathways.

METHODS

MDA-MB-231 cells were treated with wortmannin 0-200 nM for 4 h. Restoration of Akt activity was evaluated by transfection of cells with constitutively active myristoylated Akt (myr-Akt). NF-κB, MMP-9 and IL-8 proteins were detected by electrophoretic mobility shift assay, Western blot or enzyme-linked immunosorbent assay. The chicken embryo chorio-allantoic membrane assay, cell motility and migration assays were used to evaluate angiogenesis and invasion in vitro. A mouse pseudo metastatic breast cancer model was used to assess the effects of wortmannin on metastasis and angiogenesis in vivo.

RESULTS

Wortmannin inhibited the phosphorylation of Akt, upregulation of NF-κB, MMP-9, IL-8, and in vitro cell invasion and angiogenesis, in a dose-dependent manner. Transfection of myr-Akt reversed the cellular and biochemical effects of wortmannin in vitro. Wortmannin also significantly inhibited tumour metastasis and angiogenesis in vivo.

CONCLUSION

The findings of the present study suggest that wortmannin inhibits metastasis and angiogenesis in breast cancer cells via PI3K/Akt/NF-κB-mediated MMP-9 and IL-8 signalling pathways.