PTCH1 and acute myeloid leukemia: Consistent with AML heterogeneity, it was shown that the core components that mediate the HH signal response, PTCH1, SMO, GLI1, GLI2, and GLI3, are differentially expressed among AML patient samples (Bai et al., 2008; Kobune et al., 2009; Kobune et al., 2012; Wellbrock et al., 2015; Chaudhry et al., 2017).