The KYNU Knockout HCT 116 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population targeting the KYNU gene in the HCT 116 human colorectal carcinoma cell line. This loss-of-function model disrupts kynureninase activity, the pyridoxal phosphate-dependent enzyme central to the kynurenine pathway. The polyclonal format provides a genetically diverse pool of edited alleles, enabling robust functional studies without clonal selection biases.
HCT 116 is an epithelial, adherent colorectal carcinoma line from a male patient, characterized by MSI-high status due to MLH1 deficiency and oncogenic BRAF V600E, KRAS G13D, and PIK3CA mutations. These features make it a key model for studying tumorigenesis, mismatch repair defects, and drug resistance, with widespread use in cancer biology.
Kynureninase (KYNU) hydrolyzes kynurenine to anthranilic acid and 3-hydroxykynurenine to 3-hydroxyanthranilic acid, linking tryptophan catabolism to NAD+ biosynthesis and AHR signaling. KYNU expression is induced by IFNG, TNF, and IL1B via STAT1/NFKB, and it operates downstream of IDO1/TDO2. KYNU disruption causes accumulation of kynurenine and 3-hydroxykynurenine, which serve as endogenous AHR ligands, promoting transcription of AHR target genes such as CYP1A1 and CYP1B1. This metabolic shift also redirects flux toward kynurenic acid production, altering cellular NAD+ pools and immune-modulatory metabolite profiles.
In HCT 116 cells, KYNU knockout simulates metabolic reprogramming seen in tumors with high IDO1/TDO2 activity. Elevated AHR signaling fosters an immunosuppressive microenvironment by inducing Treg differentiation and suppressing T cell responses. The model allows dissection of how kynurenine pathway metabolites drive immune evasion, proliferation changes, and therapeutic resistance in MSI-high colorectal carcinoma.
Applications include cancer metabolism and tumor immunology research, IDO1/TDO2 inhibitor screening, and NAD+ biology studies. Experimental readouts may involve LC-MS quantitation of tryptophan metabolites, RT-qPCR for AHR targets, Western blotting, T cell co-culture suppression assays, flow cytometry, and xenograft models. For inquiries, please contact Ascent Research.
