FOXC2 and breast carcinoma: Knock-down of Foxc2/FOXC2 in murine mammary carcinoma 4T1-TVM cells (Fig 3A, 3B and S3A) and human MDA-MB-231 claudin-low breast cancer cells (Fig 3A, 3C and S3B), with two different shRNAs, consistently suppressed network formation.