Fig. 5.

Three possible mechanisms of Fas-mediated anoikis. Elevated Fas expression levels result in the formation of downstream FADD and activation of caspase. A Firstly, the increase in the transcription level of Fas ligand FasL leads to the increase in the transcription level of receptor Fas and induces the formation of FADD. B Secondly, the increased expression level of Fas may be due to the decreased degradation of lysosomes through vesicle sorting through endocytosis, which leads to the increased accumulation of Fas in endosomes and the increased location of Fas to the plasma membrane surface dependent on Rab11-mediated recirculation and activation of downstream FADD. C The third is that RIP shuttles between Fas and FAK to regulate anoikis. RIP can form complexes with Fas or FAK to activate different signaling pathways under different conditions