FASLG and cancer: Following cytokine treatment, NK cells convert (turn into) lymphokine-activated killer (LAK) cells, subsequently producing cytokines and upregulating the factors such as adhesion molecules, perforin, granzymes, FasL, and TRAIL [183,184,185,186,187], thereby enhancing their capability to detect and adhere to cancer cells, triggering various activity to eliminate cancer cells through perforin/granzyme-dependent necrosis [188,189] and/or Fasl/TRAIL-mediated apoptosis [184,185,186,187].