TGFB1 and cancer: As well, since atherosclerosis is promoted by M1 macrophages [46] and asthma and allergies are worsened by M2 skewed macrophages, reducing ATRA, PGE2 and/or TGFβ may prove efficacious in reducing the symptoms of allergies, asthma and the incidence and progression of cancer while increasing these factors might reduce certain forms of heart disease.