VEGFA and small cell lung carcinoma: As a key transcriptional regulator, HIF-1α plays a central role in the adaptation of tumor cells to hypoxia and helps to regulate the expression of muitiple cytokines, such as vascular endothelial growth factor-A (VEGF-A), and promotes the proliferation [5] and angiogenesis potential [6] of small cell lung cancers (SCLCs).