STAT3 and neoplasm: In head and neck squamous cell carcinoma, STAT3 phosphorylation is a consequence of increased IL‐6 production by tumour cells.39 Increased expression of the G‐CSF receptor is observed in high‐grade ovarian epithelial tumours, and cell culture experiments suggest that G‐CSF contributes to JAK/STAT activation in this disease.40 Given that hypoxia stimulates the proliferation of PASMCs, thereby promoting pulmonary blood vessel remodelling,41 we thus utilized TG101043 (TG), a selective JAK2 inhibitor, to elucidate the effect of JAK2 on PASMC proliferation following hypoxic insult.