FGF2 and idiopathic pulmonary fibrosis: The in vitro efficacy of nintedanib was explored in vascular endothelial growth factor (VEGF)- or fibroblast growth factor (FGF)-2-stimulated human umbilical vascular endothelial cells (HUVECs), pericytes stimulated with platelet driven growth factor (PDGF) and FGF-2, and TGF-β-induced primary culture of lung fibroblasts from IPF patients [7].