Stromal cells can mediate immune-suppression and protect tumor cells from cytotoxicity via secretion of soluble factors including immune suppressive mediators such as IL-10, TGF-β and PGE2 or growth factors such as stem cell factor (SCF), IL-7, IL-15, CXCL-12 among others21,33. Here, CXCL12 is linked to neoplasm.