PGF and neoplasm: Tumor angiogenesis is regulated by a variety of cytokines including VEGF, placenta growth factor (PLGF), transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), and angiopoietin (Galvano et al., 2019).