TNFSF10 and cancer: Apart from sparking the development of TRAIL-receptor (TRAIL-R) agonists (TRAs) for clinical application as potential novel cancer therapeutics, this discovery resulted in intense world-wide research efforts to unravel the signal transduction machinery triggered by this ligand, especially concerning apoptosis induction in cancer cells and how resistance to TRAIL-induced apoptosis may be overcome when it is encountered.