IL4 and neoplasm: As would be expected, TAMs possess M2-like traits; Tumour cells and the tumour microenvironment release a variety of factors that facilitate this, including IL-4, IL-6, IL-10, PGE2, TGF-β1 and CSF-1, expressed by tumour cells, as well as IL-10, PGE2 and MMP-7 expressed by TAMs.