CXCL12 and neoplasm: However, TAMs can be transformed from the M1 to M2 phenotype to promote tumor angiogenesis by producing pro-angiogenic growth factors (e.g., VEGF, EGF, FGF family, and PDGF-β), angiogenic CXC chemokines (e.g., CXCL8/IL-8 and CXCL12, also known as SDF-1), and angiogenesis-associated factors (e.g., TGF-β, thymidine phosphorylase) (Muller et al. 2001; Lewis and Pollard 2006; Kim et al. 2012; Hughes et al. 2015).