LIF and neoplasm: With the advancement of research, M2-type TAMs can be further subdivided into M2a, involved in tissue fibrosis (induced by IL-4 or IL-13), M2b, which promote tumor progression (induced by immune complexes in conjunction with IL-1β or LPS), M2c, responsible for tissue remodeling (induced by IL-10, TGF-β, or glucocorticoids), and M2d, which promote angiogenesis (induced by IL-6, leukemia inhibitory factor (LIF), and adenosine) (6, 17, 18, 22) (Table 1).