To further confirm whether PinX1 regulated MMP-9 expression via the NF-κB signaling pathway in human breast cancer cells, we transfected NF-κB-p65 siRNA (Santa Cruz) into PinX1KD-MDA-MB-231 cells and PinX1KD-BT-549 cells. Here, NFKB1 is linked to breast carcinoma.