Charakterizace TRAILem indukované, receptor-specifické signalizace v nádorových buňkách.

Peterka, Martin

TNF-related apoptosis-inducing ligand (TRAIL) is a member of TNF family expressed mainly by hematopoietic cells. TRAIL brought significant attention mainly for its ability to trigger apoptosis in a number of cancer cells. In addition to apoptosis, TRAIL can induce several other signaling pathways such as activation of MAP kinases or canonical NF-B signaling. Human TRAIL can bind to five receptors but only two of them (death receptors TRAIL-R1/DR4 and TRAIL-R2/DR5) can trigger TRAIL-mediated apoptotic and non-apoptotic signaling in target cells. Both receptors are ubiquitously expressed on normal and cancer cells, but the relative contribution of DR4 and DR5 to TRAIL-induced signaling is not well known. Using DR4/DR5-specific variants of TRAIL, we examined how individual receptor contributes to the induction of apoptosis and NF-B, JNK, p38, ERK1/2 and TAK1 signaling pathways in selected colorectal cells. We found that in DLD-1 cells, apoptosis and activation of JNKs are mainly mediated by DR4-selective ligand. In TRAIL-resistant HT-29 cells, we show that though DISC formation and activation of caspase-8 proceeds mainly via DR4-specific signaling, activation of NF-B pathway is mainly triggered by DR5 selective ligand. In other cells and analyzed signaling pathways both receptor-specific ligands triggered very...

guest :: login Digital Repository
		Search		Submit		Help		About