PTCH1 and cancer: Cancer cells pump chemotherapeutic agents out of the cells using the http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=153 (MRPs, also known as MDR or the ABCC family of transporters) and the Hedgehog receptor Patched 1 (protein patched homolog 1, PTCH1), which reduces drug accumulation within cancer cells and, thereby, lower drug efficacy (Amiri‐Kordestani, Basseville, Kurdziel, Fojo, & Bates, 2012; Bidet et al., 2012).