The effects of TWEAK on the cellular programming of gene expression are likely to be multifactorial and may underlie the alterations in cellular processes—such as cell proliferation, apoptosis, and angiogenesis—observed in inflammatory and autoimmune diseases, as well as in cancer, which may well justify the use of TWEAK as a biomarker of these pathological conditions [33]. This evidence concerns the gene TNFSF12 and cancer.