CASP8-associated protein 2 is a protein that in humans is encoded by the CASP8AP2 gene.

This protein is highly similar to FLASH, a mouse apoptotic protein identified by its interaction with the death-effector domain (DED) of caspase 8. Studies of FLASH protein suggested that this protein may be a component of the death-inducing signaling complex that includes Fas receptor, Fas-binding adapter FADD, and caspase 8, and plays a regulatory role in Fas-mediated apoptosis. Alternative splicing results in multiple transcript variants encoding the same protein.[provided by RefSeq, Nov 2008].
Function: Participates in TNF-alpha-induced blockade of glucocorticoid receptor (GR) transactivation at the nuclear receptor coactivator level, upstream and independently of NF-kappa-B. Suppresses both NCOA2- and NCOA3-induced enhancement of GR transactivation. Involved in TNF-alpha-induced activation of NF-kappa-B via a TRAF2-dependent pathway. Acts as a downstream mediator for CASP8-induced activation of NF-kappa-B. Required for the activation of CASP8 in FAS-mediated apoptosis. Required for histone gene transcription and progression through S phase.