Similarly, the presence of S1P induces Notch signaling and augments mammosphere-forming capacity in breast CSCs, and S1P3 is highly expressed in ALDH-positive cells derived from breast cancer patients, suggesting that the SPHK1/S1P/S1P3 axis is important for the maintenance of stem-like features [49]. The gene discussed is MBTPS1; the disease is breast carcinoma.