EPAS1 and neoplasm: The initial decrease in HIF-2α expression is consistent with the differentiating properties of A1AR; HIF-2α has been found to be colocalised with stem cell markers in tumour specimens45 and to have a pivotal role in maintaining stem cells in an undifferentiated state.60 In contrast, the increase in the HIF-2α mRNA levels that was observed on the 7th day may be associated with effects on other signalling pathways in the CHA-differentiated CSCs.