Additionally, the growth factor HGF secreted by pancreatic stellate cells activates the expression of c‐MET, leading to the nuclear translocation of YAP and stabilising the structure of HIF‐1α, which promotes the tumour cell spheroidisation ability and upregulates the expression of stemness marker genes NANOG and OCT4.204, 205. This evidence concerns the gene YAP1 and neoplasm.