The M2 TAMs can directly activate angiogenesis through the release of VEGF, bFGF, and PlGF or indirectly activate angiogenesis through the release of matrix metalloproteinases (MMPs) to remodel the extracellular matrix and to improve the migration of endothelial cells (47), which could form new blood vessels and accelerate tumor progression. Here, PGF is linked to neoplasm.