VEGFA and small cell lung carcinoma: In in vitro lung cancer studies, catecholamine treatment drove macrophages toward a tumor-supportive M2 polarization via adrenergic signaling while also enhancing the expression of vascular endothelial growth factor (VEGF), thereby promoting tumor angiogenesis in the HCC827 human NSCLC cell line and the H446 small-cell lung cancer cell line.