Macrophages, specifically the M1 and M2 subtypes, play critical roles in tumor development and progression.225,226 M1 macrophages can kill tumor cells, while M2 macrophages promote tumor growth, invasion, and metastasis.227 Dysregulation of the mTOR pathway has been implicated in the polarization and function of macrophages. This evidence concerns the gene MTOR and neoplasm.