68). In NSCLC the expression of HH signalling components is higher than in the non-tumoural parenchyma and associates with high grade, poor survival and metastases (Refs 172, 173). In NSCLC, GLI1 regulates cell proliferation in cell-autonomous manner. Moreover, increased production of SHH by tumour cells leads to activation of fibroblasts in the tumour-associated stroma, indicating the presence of paracrine HH signalling (Refs 69, 174). Here, SHH is linked to neoplasm.