The CASP7 Knockout HGC-27 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HGC-27 human gastric carcinoma cell line, engineered for targeted disruption of the CASP7 gene. This loss-of-function model provides a heterogeneous cell pool with abrogated caspase-7 expression, enabling robust investigation of apoptosis executioner caspase biology without monoclonal selection biases. The polyclonal format preserves phenotypic diversity while ensuring functional knockout across the population, making it suitable for pooled functional studies and downstream assays where clonal uniformity is not required.
HGC-27 is an adherent epithelial cell line established from the metastatic lymph node of a patient with gastric adenocarcinoma, and it retains key characteristics of gastric cancer cells, including aberrant signaling, migratory capacity, and resistance to apoptosis. This line is widely employed in gastric cancer research for studying tumor progression, metastasis, and therapeutic responses. The HGC-27 background harbors genetic alterations typical of gastric malignancies, offering a clinically relevant context for dissecting caspase-7-mediated pathways in a disease setting where apoptosis evasion is a hallmark.
CASP7 encodes caspase-7, an executioner caspase that is proteolytically activated by initiator caspases such as caspase-8 and caspase-9 during apoptosis. Upon activation, caspase-7 cleaves a range of substrates including PARP1, lamin A/C, vimentin, ??-tubulin, and ROCK1, orchestrating DNA fragmentation, nuclear dismantling, and cytoskeletal reorganization. Its activity is tightly regulated by upstream complexes: the extrinsic pathway engages death receptors (e.g., Fas, TNF-R1) through adaptor FADD and procaspase-8, while the intrinsic pathway involves cytochrome c/Apaf-1-mediated activation of procaspase-9. Caspase-3 can also contribute to caspase-7 processing. Inhibitory factors such as XIAP and cIAP1/2 bind and suppress caspase-7; this inhibition is relieved by mitochondrial release of Smac/DIABLO following Bak/Bax-mediated mitochondrial outer membrane permeabilization. Bid, cleaved by caspase-8, links the extrinsic and intrinsic routes.
In the HGC-27 gastric cancer model, CASP7 knockout disrupts the execution phase of apoptosis, providing a unique tool to study the rewiring of cell death pathways. Gastric adenocarcinomas frequently exhibit dysregulated apoptosis, contributing to chemoresistance and tumor survival. This polyclonal knockout system permits analysis of how loss of caspase-7 affects sensitivity to chemotherapeutics, death receptor ligands, or BH3 mimetics, and can reveal compensatory engagement of other executioner caspases or pyroptotic machinery. It also serves as a platform to interrogate non-apoptotic functions of caspase-7 recently implicated in inflammation and cell remodeling.
Key applications include apoptosis mechanism studies, drug resistance profiling in gastric cancer, and screening for caspase-7 modulators. Researchers can employ Western blotting to confirm loss of caspase-7 and assess PARP cleavage, fluorogenic substrate-based activity assays to quantify residual executioner activity, flow cytometry with Annexin V/PI to measure apoptotic response, TUNEL for DNA fragmentation, and co-immunoprecipitation to map altered protein interactions. The model is also amenable to CRISPR knockout validation by qRT-PCR and complementation experiments. These polyclonal knockout cells are a powerful resource for dissecting apoptosis signaling networks and advancing anti-cancer therapeutics. Researchers are invited to contact Ascent Research for further information or to discuss custom applications.
