CSCs Self-renewal may be retained through multiple endogenous signaling paths, including Wnt, Bmp, Pten, Notch, B cell–specific Moloney murine leukemia virus integration site 1 (Bmi1), TGF-β, and Hedgehog [80–86] that would be often actuated in human cancers [85, 87, 88]. The gene discussed is BMI1; the disease is cancer.