Shh plays a major physiological role in embryonic development where it is critical for appropriate growth of limbs, skin, neuronal progenitor cells, inner ear, eye, taste buds and hair follicles.1 The role of Shh is significantly diminished in postnatal and adult organisms, although it is important in the maintenance of stem cells, and for tissue repair and regeneration.2 However, Shh expression is regained in many types of cancer, and is widely recognised as a driver of carcinogenesis.3 Here, SHH is linked to cancer.