The NOTCH receptors are a membrane receptor proteins responsible for proliferation of cells and angiogenesis of the tumorNOTCH overexpression is observed in ovarian cancer, together with the downstream components of this pathway, like VEGF, VEGFR1, DLL4, and JAG1Tumor hypoxia enhances NOTCH signaling, stemness, and migration of OCSCsNOTCH pathway upregulates NANOG, OCT4, and ABCB1 transporter, thus increasing chemoresistance. The gene discussed is POU5F1; the disease is ovarian cancer.