IGF1 and posterior cortical atrophy: Consistent with the reported requirement of IGF and FGF in establishing a regulatory SC niche in cultured human ESCs22, and promotion by STAT3 of stem-like phenotypes in normal prostate and PCa cells23, 24, basal cells exhibited a high sensitivity to inhibitors of FGFR, IGF1R and STAT3 signalling (Fig. 3b–d).