TNF and lung cancer: In coculture, U937 macrophages have been shown to secrete TNF-α and IL-1α (IL-1α not at high doses) after irradiation of NCI-H446 lung cancer cells with γ-rays (137Cs Source, 8 Gy) but only TNF-α after irradiation with accelerated carbon ions (290 MeV/n, LET 13 keV/μm, 2 Gy) (99).