OLR1 and breast cancer: In another study, MCF7 breast cancer cells cocultured with immortalized lymphatic endothelial cells to form spheres had higher 15-LOX-1 expression than monolayer cell formations; short hairpin RNA (shRNA) knockdown of 15-LOX-1 reduced MCF7 xenograft formation in mice, and a trend was observed for association between 15-LOX-1 immunohistochemical (IHC) expression in human sentinel lymph node metastases and poor prognosis (P = 0.0567) 23.