The CASP7 Knockout HT29 Polyclonal Cells consist of a heterogeneous population of HT29 colorectal adenocarcinoma cells bearing CRISPR/Cas9-mediated disruption of the CASP7 gene. This loss-of-function model abrogates expression of the executioner caspase-7, enabling systematic study of its pivotal roles in apoptosis and cellular homeostasis. The polyclonal format preserves genetic diversity, mimicking tumor heterogeneity and facilitating pooled functional analyses.
The parental HT29 cell line, derived from a primary colorectal adenocarcinoma of a 44-year-old Caucasian female, is a well-characterized model of intestinal epithelial cells. HT29 cells carry mutations such as BRAF V600E and TP53 R273H, and they are extensively employed for investigating colorectal cancer pathobiology, including aberrant signaling, differentiation, and mechanisms of drug resistance. Their epithelial origin and tumorigenic properties make them ideal for studies of apoptosis evasion in colorectal adenocarcinoma.
Caspase-7, encoded by CASP7, is an executioner caspase activated proteolytically by initiator caspases (caspase-8, -9, -10) and granzyme B in response to apoptotic cues. Active caspase-7 cleaves substrates such as PARP1 to halt DNA repair, lamin A/C to dismantle the nuclear lamina, and DFF45/ICAD to release CAD for DNA fragmentation, collectively enforcing apoptotic cell death. Its activity is tightly controlled by the IAP proteins XIAP and cIAP1/2, with Smac/DIABLO facilitating derepression. In HT29 cells, caspase-7 functions downstream of mitochondrial outer membrane permeabilization driven by BAX/BAK, Apaf-1, and cytochrome c, and also integrates extrinsic signals from death receptors including Fas and TNFRS.
Disruption of CASP7 in HT29 cells directly addresses the evasion of apoptosis, a hallmark of colorectal cancer progression and chemoresistance. As a downstream executioner, caspase-7 mediates the lethal outcomes of the p53 tumor suppressor pathway and TNFR signaling, enabling dissection of these cascades independent of initiator caspase activation. Clinically, reduced caspase-7 expression correlates with poor response to standard chemotherapeutics such as 5-fluorouracil and oxaliplatin, highlighting this polyclonal knockout model’s utility for drug resistance studies and for screening agents that restore apoptosis sensitivity.
Researchers can utilize these cells in a variety of assays, including western blotting to monitor cleavage of apoptotic substrates, luminescent caspase activity measurements, Annexin V/propidium iodide flow cytometry for cell death quantification, and MTT viability assays. The polyclonal knockout pool is well-suited for caspase substrate identification, drug sensitivity profiling, colony formation assays, and RT-qPCR analysis of apoptosis gene networks. This product provides a versatile platform for apoptosis signaling research in colorectal cancer. For further details, please contact Ascent Research.
