The GPX4 Knockout 769-P Polyclonal Cells are a CRISPR/Cas9-edited polyclonal cell population derived from the human 769-P clear cell renal cell carcinoma line, carrying a targeted disruption of the GPX4 gene. This loss-of-function model circumvents single-cell cloning, providing a heterogeneous pool of knockout alleles suitable for bulk assays and large-scale functional screens requiring a uniform GPX4-null background.
The 769-P cell line originates from a primary clear cell renal cell carcinoma (ccRCC) and is widely used as an in vitro model for RCC drug response and metabolic studies. These adherent epithelial cells retain key ccRCC features, including dysregulated hypoxia-inducible factor signaling and altered lipid metabolism, providing a physiologically relevant background for investigating ferroptosis and redox homeostasis in renal cancer.
GPX4 is a selenoenzyme that suppresses ferroptosis by reducing phospholipid hydroperoxides to lipid alcohols, using glutathione (GSH) as a cofactor. Its expression is transcriptionally regulated by NRF2 (NFE2L2) and repressed by p53 via SLC7A11 downregulation; ATF4 and selenium availability also modulate GPX4 levels. The enzyme counteracts lipid peroxidation driven by ACSL4, LPCAT3, and lipoxygenases such as ALOX5, thereby preventing ferroptotic cell death. Consequently, GPX4 deletion results in unchecked lipid peroxide accumulation and ferroptosis execution.
In 769-P cells, GPX4 knockout eliminates the primary ferroptosis defense, rendering the cells highly susceptible to oxidative stress and lipid peroxidation, particularly under conditions of cystine deprivation or direct GPX4 inhibition. This sensitization is especially pertinent to ccRCC, where metabolic rewiring often creates exploitable redox vulnerabilities. The knockout model thus enables dissection of ferroptosis-related cell death pathways and identification of synthetic lethal interactions within the renal carcinoma context.
Applications include screening ferroptosis-inducing compounds, mechanistic studies of lipid peroxide signaling, and validation of GPX4-dependent pathways. Typical assays incorporate western blotting for GPX4, C11-BODIPY-based lipid peroxidation analysis, cell viability tests with erastin or RSL3, glutathione quantification, and flow cytometry for lipid ROS. The cells are also suitable for rescue experiments, metabolic profiling, and co-culture models. For further technical inquiries, please contact Ascent Research.
