TGF-β induced EMT mediated by inflammatory cells in the tumor microenvironment is promoted by leukotriene B4 receptor 2, which, in response to leukotriene B4, activates reactive oxygen species (ROS) and NF-κB transcriptional activity that facilitates the establishment of EMT by TGF-β42. The gene discussed is TGFB1; the disease is neoplasm.