In addition, UDP increased MMP-9 enzyme activity, not only in MDA-MB-231 cells, but also in BT549, T47D, MDA-MB-468, MDA-MB-453 and MCF-7 cells, suggesting the extensive role of UDP/P2Y6 in breast cancer cell metastasis (Figure 6B). The gene discussed is P2RY6; the disease is breast cancer.