The BAX Knockout SK-HEP-1 Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal population of human hepatic adenocarcinoma cells harboring targeted disruption of the BAX gene. This polyclonal culture contains a spectrum of edited alleles, creating a heterogeneous loss-of-function model for the pro-apoptotic BAX protein without relying on single-cell-derived clones. The knockout was generated through CRISPR/Cas9-mediated gene disruption, offering a robust tool for apoptotic signaling studies.
The parental SK-HEP-1 cell line was derived from ascites of a patient with hepatic adenocarcinoma and displays epithelial morphology. SK-HEP-1 is a well-established model for hepatocellular carcinoma research and is frequently used to explore hepatic drug metabolism and toxicity, making it an appropriate host for dissecting connections between oncogenic pathways and programmed cell death.
BAX is a pivotal pro-apoptotic member of the BCL2 family that operates at the mitochondrial outer membrane to trigger permeabilization and cytochrome c release. Upstream, BAX is regulated by the tumor suppressor p53, stress-activated JNK kinases, and BH3-only proteins such as BID, BIM, PUMA, and NOXA, which relay diverse death signals. Upon activation, BAX interacts with anti-apoptotic BCL2 and BCL-xL, cooperates with BAK, and associates with VDAC to form mitochondrial pores. Downstream events include cytochrome c-dependent assembly of the APAF1/caspase-9 apoptosome, leading to caspase-3 activation and cleavage of substrates like PARP. Thus, BAX functions as an essential integrator in the intrinsic apoptosis pathway, converting upstream signals into caspase-mediated proteolysis.
Disruption of BAX in SK-HEP-1 cells eliminates a central effector of intrinsic apoptosis, conferring resistance to chemotherapeutic agents, growth factor deprivation, and irradiation. This phenotype mirrors the apoptosis evasion commonly observed in liver tumors, where tumor cells frequently downregulate pro-apoptotic machinery to sustain survival. By removing BAX, the balance of BCL2 family interactions shifts, potentially amplifying survival signals from pathways such as PI3K/AKT. The resulting polyclonal knockout model is highly relevant for investigating mechanisms of drug resistance in hepatocellular carcinoma and for testing whether candidate therapeutics require an intact apoptosis cascade for efficacy.
Key applications include apoptosis mechanism studies comparing cytochrome c release, caspase-9/3 activity, and Annexin V/PI flow cytometry between knockout and parental cells. The polyclonal population is also suited for high-throughput drug sensitivity screens (e.g., MTT assay) to identify compounds that overcome BAX deficiency or trigger alternative cell death pathways. Moreover, these cells facilitate exploration of crosstalk between apoptosis and oncogenic signaling and enable validation of BAX interactions with BCL2, BAK, and VDAC via co-immunoprecipitation and Western blotting. For further information, please contact Ascent Research.
