NOTCH3 and breast cancer: On the basis of these results, we developed unique NOTCH3-knockout breast cancer cells (vMCF-7Raf-1 1GXCRISPR-NOTCH3) to abrogate NOTCH3 expression and evaluate the causative role of NOTCH3 signaling in promoting stemness and invasive properties of vMCF-7∆Raf1 1GX cells.