MMP9 and breast cancer: On the other hand, melittin suppressed the HIF-1α signaling pathway in the breast adenocarcinoma cell line MDA-MB-231 through downregulation of NF-κB gene expression [41] and inhibited the EGF-induced MMP-9 expression via blocking the NF-κB and PI3K/Akt/mTOR pathways in two breast cancer cells, MDA-MB-231 and MCF-7 cells [42].