The AADAT Knockout HCT 116 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HCT 116 human colorectal carcinoma cell line, featuring targeted disruption of the AADAT gene. This polyclonal pool provides a loss-of-function model for studying aminoadipate aminotransferase (kynurenine aminotransferase-2) in a mismatch repair-deficient, KRAS- and PIK3CA-mutated epithelial background.
HCT 116 is a well-established human colorectal carcinoma cell line with epithelial morphology, isolated from a male patient. It harbors KRAS G13D and PIK3CA H1047R activating mutations and exhibits microsatellite instability (MSI-high) due to MLH1 promoter hypermethylation. These genetic features make HCT 116 a widely used model for colorectal cancer research, drug screening, and xenograft studies, particularly valuable in investigations of DNA repair deficiency and targeted therapy response.
The AADAT gene encodes aminoadipate aminotransferase, a pyridoxal phosphate-dependent enzyme that catalyzes the transamination of L-kynurenine to kynurenic acid and L-2-aminoadipate to 2-oxoadipate. Within the kynurenine pathway of tryptophan metabolism, AADAT functions downstream of IDO1 and TDO2, which generate kynurenine. Kynurenic acid antagonizes NMDA receptors and ??7 nicotinic acetylcholine receptors, modulates AhR, and signals through GPR35. Pro-inflammatory cytokines IL-1??, TNF-??, and IFN-??, along with TGF-??, regulate AADAT expression, while enzymatic activity depends on pyridoxal phosphate and substrate availability.
In HCT 116 cells, AADAT knockout is expected to abolish kynurenic acid production, disrupting tryptophan catabolism and potentially altering cellular redox balance and energy metabolism. Given the role of the kynurenine pathway in immune evasion and tumor microenvironment modulation, this model provides insight into how colorectal cancer cells redirect tryptophan metabolism to affect NMDA receptor and AhR downstream signaling. The MSI-high background, combined with KRAS and PIK3CA mutations, makes this knockout particularly relevant for studying metabolic adaptations in mismatch repair-deficient tumors.
This polyclonal knockout cell population supports metabolomic profiling via LC-MS for kynurenine and kynurenic acid, enzyme activity assays, and immunoblotting. Applications include assessing cell proliferation, migration, invasion, apoptosis, and drug sensitivity to kynurenine pathway modulators, as well as cytokine response assays. For further technical details, contact Ascent Research.
