The BID Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population of the human SK-HEP-1 hepatocellular carcinoma line, with targeted disruption of the BID gene, abolishing expression of the pro-apoptotic BH3-only protein BID. This polyclonal pool, lacking single-cell cloning, provides a robust population-level knockout for apoptosis studies. It serves as a tool for investigating the crosstalk between extrinsic death receptor pathways and intrinsic mitochondrial apoptosis in hepatic tumor biology.
The SK-HEP-1 host cell line, derived from the ascitic fluid of a liver adenocarcinoma patient, is a well-characterized human hepatocellular carcinoma model used extensively in liver cancer research, including studies of pathogenesis, metastasis, and drug resistance. Its adherent growth and molecular features enable diverse assays, such as mitochondrial function and protein interaction analyses.
BID is a pivotal pro-apoptotic BH3-only protein that connects extrinsic death receptor signaling to the mitochondrial intrinsic apoptosis pathway. Upon engagement of death receptors (e.g., FAS, TRAIL), caspase-8 cleaves BID into truncated tBID, which translocates to the mitochondrial outer membrane. There, tBID directly interacts with BAX and BAK, promoting their oligomerization and mitochondrial outer membrane permeabilization, a process counteracted by anti-apoptotic BCL-2, BCL-XL, and MCL-1. The resulting cytochrome c release facilitates apoptosome assembly with APAF-1, leading to caspase-9 and executioner caspase-3/7 activation. BID expression is regulated by p53, and its activation is also mediated by granzyme B, thereby integrating signals from TNF family ligands, genotoxic stress, and immune effector pathways to dictate cell fate.
In hepatocellular carcinoma, apoptosis evasion drives tumor progression and therapeutic resistance. BID knockout in SK-HEP-1 cells enables interrogation of the mitochondrial apoptosis pathway’s role in liver cancer cell survival. This model is valuable for studying resistance to apoptosis-inducing therapies, including TRAIL-based and chemotherapeutics. Comparative analyses of BID-proficient and -deficient cells can delineate contributions of death receptor signaling, BCL-2 family interactions, and mitochondrial integrity. Moreover, it supports exploration of synthetic lethal vulnerabilities in liver cancer.
This BID knockout product supports a wide array of experimental workflows. Typical applications include Western blotting to assess BID cleavage and caspase activation kinetics, flow cytometry with Annexin V/propidium iodide staining for quantifying apoptosis, and JC-1-based mitochondrial membrane potential measurements. Co-immunoprecipitation experiments can map tBID??s interactions with BAX, BAK, or VDAC, while cell viability assays (MTT/XTT) evaluate responses to death ligands like TNF-alpha or TRAIL. The model facilitates dissection of p53-dependent and -independent apoptotic programs, as well as analysis of granzyme B-mediated cell killing. For technical inquiries or ordering support, please contact Ascent Research.
