IL4 and neoplasm: Th2 cells, basophils, and eosinophil release inducers such as IL-4, IL-13, and tumor cells themselves release cytokines such as macrophage colony-stimulating factors (CSFs) and transforming growth factor (TGF) β that drive this M2 polarization.19–23 The tumor’s hypoxic conditions and lactic acid presence are also involved in this process.