CSF2 and neoplasm: Consistently, a further study from the same group demonstrated that tumor-derived cytokines, such as G-CSF and GM-CSF, induce the expression of lipid transport receptors in intratumoral MDSCs through the activation of STAT3 and STAT5, which leads to increased uptake of lipids that are present at high concentrations in the tumor microenvironment; intracellular accumulation of lipids in turn increases the oxidative metabolism and suppressive activity of MDSCs (187).