The GSDME Knockout 786-O Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population derived from the 786-O renal adenocarcinoma line, featuring targeted disruption of the GSDME gene. This knockout model enables loss-of-function studies of gasdermin E, a key pyroptosis executor and tumor suppressor. The polyclonal format provides a heterogeneous cell pool that better recapitulates tumor heterogeneity, offering a versatile tool for functional genomics, drug screening, and mechanistic investigations without the artifacts of clonal selection.
The parental 786-O cell line is a human clear cell renal cell carcinoma (ccRCC) model with a naturally occurring VHL mutation, leading to constitutive HIF pathway activation. These epithelial tumor cells retain hallmark characteristics of ccRCC, including anchorage-independent growth and tumorigenicity. The VHL-null background is particularly relevant as GSDME is frequently silenced by promoter methylation in ccRCC, making this knockout model ideal for examining the interplay between tumor suppressor pathways and pyroptotic signaling.
GSDME is a substrate of caspase-3, which cleaves it at Asp270 to release the N-terminal pore-forming domain. This fragment oligomerizes in the plasma membrane phospholipids, forming pores that mediate pyroptotic cell death and release of pro-inflammatory factors including IL-1??, IL-18, and HMGB1. Upstream activators include TNF, TRAIL, granzyme B, and chemotherapeutics like cisplatin and doxorubicin. In cancer, GSDME silencing via methylation promotes immune evasion and chemoresistance, whereas its re-expression restores pyroptosis and enhances anti-tumor immunity through inflammatory cytokine release and immunogenic cell death.
In the VHL-deficient 786-O context, GSDME knockout provides a physiologically appropriate model to dissect pyroptosis-dependent tumor suppression. Loss of GSDME allows direct assessment of its role in chemotherapy sensitivity, immune cell recruitment, and progression of renal cell carcinoma. This system is valuable for studying how re-expression of GSDME or pharmacological induction of pyroptosis can overcome drug resistance, given the frequent downregulation of GSDME in ccRCC and its association with poor prognosis.
This knockout model supports diverse assays including Western blotting for GSDME cleavage, LDH release and Annexin V/PI staining to quantify pyroptosis, MTT viability assays following drug treatment, and ELISA for IL-1??/IL-18 secretion. Additional applications encompass colony formation assays for long-term survival, immunofluorescence to visualize GSDME pore formation, and high-throughput screening for pyroptosis-inducing compounds. It is an essential tool for research into renal cell carcinoma biology, tumor immunology, and the development of therapies that exploit the caspase-3/GSDME pyroptotic axis. For further information, please contact Ascent Research.
