Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), also known as CD253 or TNFSF10, can be produced and secreted by most normal tissue cells. TRAIL proteins are available in two forms: membrane-bound (full-length TRAIL) and soluble (sTRAIL). In vivo, only the membrane-bound form exists, while the soluble polypeptide (sTRAIL), which is formed in the extracellular region of TRAIL, has the full biological activity of the membrane-bound TRAIL. Both of them are able to bind to specific receptors on the cell membrane and rapidly induce the expression of TRAIL through intracellular signal transduction. They can rapidly induce apoptosis in cells expressing TRAIL-specific receptors. TRAIL has a broad spectrum of action and can induce apoptosis in a variety of tumor cells in the colon, lung, breast, kidney, brain and skin, and is considered as a promising broad-spectrum anti-cancer molecule.