The CASP8 Knockout AGS Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human gastric adenocarcinoma cell line AGS, with targeted disruption of the CASP8 gene. This polyclonal pool enables loss-of-function studies of caspase-8 in a heterogeneous genetic background, minimizing clonal bias and reflecting population-level responses.
The AGS cell line is an adherent epithelial model of gastric adenocarcinoma, widely used for investigating cancer biology, drug responses, and signaling pathways. Its origin from a primary gastric tumor makes it a relevant system for studying mechanisms of gastric carcinogenesis and therapeutic resistance.
Caspase-8 functions as an initiator caspase in death receptor-mediated extrinsic apoptosis. It is recruited by FADD to activated death receptors, including FAS and TRAIL receptors, where it autoproteolytically activates and then cleaves downstream caspases-3 and -7. Caspase-8 also processes BID, linking to mitochondrial cytochrome c release and APAF1/caspase-9 apoptosome formation. Interactions with c-FLIP, RIPK1, TRADD, and TRAF2 allow caspase-8 to regulate necroptosis and NF-??B signaling. Ligands TNF, FASL, and TRAIL, along with regulators c-FLIP and RIPK1, control its activity.
In AGS gastric cancer cells, CASP8 knockout blocks extrinsic apoptosis induced by death receptor agonists, facilitating study of apoptosis resistance and potential sensitization to TRAIL-based therapies. This model also unveils necroptosis as an alternative cell death pathway, since caspase-8 deficiency can unleash RIPK1-dependent necroptosis. Additionally, it permits exploration of caspase-8??s role in inflammatory signaling and its impact on gastric tumor biology.
Applications include screening death receptor agonists, evaluating chemosensitization, and dissecting necroptotic and inflammatory pathways. Compatible assays encompass Western blotting for caspase-8, cleaved caspase-3, and phospho-RIPK1; Annexin V/PI apoptosis analysis; MTS viability tests; flow cytometry; co-immunoprecipitation of caspase-8 and FADD; RT-qPCR; and caspase activity measurements. For more information, contact Ascent Research.
