A summary of various secreted factors implicated in EMT induction by stromal cells and immune cells. CAFs, CAAs and immune cells including T lymphocytes, TAMs and MDSCs could promote EMT in cancer cells through the secretion of cytokines, chemokines and growth factors, such as TGFβ, IL-6, CXCL12, CCL18, FGF and HGF. Meanwhile, cancer cells secrete various factors to stimulate CAFs or CAAs formation and recruit more Tregs, TAMs or MDSCs. CAFs: cancer associated fibroblasts; CAAs: cancer associated adipocytes; TAMs: tumor associated macrophages; MDSCs: myeloid-derived suppressor cells.