The CBS Knockout SK-HEP-1 Polyclonal Cells product is a ready-to-use, CRISPR/Cas9-edited polyclonal cell population derived from the SK-HEP-1 human hepatic adenocarcinoma cell line, in which the CBS gene has been disrupted to create a loss-of-function model. This heterogeneous knockout pool is generated through CRISPR/Cas9-mediated gene disruption, resulting in a diverse cellular population with targeted CBS inactivation, suitable for studying gene function without clonal selection artifacts. The polyclonal format provides a robust representation of the knockout phenotype across a mixed genetic background, enabling researchers to assess population-level effects on transsulfuration pathway activity and hydrogen sulfide signaling.
The host SK-HEP-1 cell line is an established human hepatic adenocarcinoma model originally isolated from the ascitic fluid of a patient with liver adenocarcinoma. SK-HEP-1 cells exhibit epithelial morphology and are widely utilized in liver cancer research to investigate tumor biology, metabolic reprogramming, and signaling pathways. This line retains key characteristics of hepatic differentiation, making it a relevant platform for examining liver-specific metabolic processes, including methionine metabolism and one-carbon metabolism, which are tightly linked to CBS function.
Cystathionine beta-synthase (CBS) catalyzes the condensation of homocysteine and serine to cystathionine, a pivotal step in the transsulfuration pathway leading to cysteine, glutathione, and hydrogen sulfide (H?S) production. CBS is regulated by heme, pyridoxal phosphate, S-adenosylmethionine, and nitric oxide, and transcribed by SP1 and NF-Y. Downstream, cystathionine is metabolized by CTH to cysteine, which generates glutathione and H?S; H?S subsequently modulates NF-??B, KEAP1, and KATP channels to influence redox balance and signaling. CBS also interacts with PRMT1 and heme oxygenase-2, integrating it into methionine metabolism and stress responses.
In SK-HEP-1 hepatoma cells, CBS knockout abolishes transsulfuration, impairing cysteine and glutathione synthesis and eliminating H?S-mediated signaling. This disruption alters redox homeostasis and homocysteine metabolism, providing a model to study liver cancer metabolic dependencies, homocystinuria-like phenotypes, and the role of H?S in tumor proliferation and apoptosis. The polyclonal knockout population avoids clonal bias, enabling robust assessment of pathway-wide transcriptional and metabolic adaptations.
Applications include Western blot and RT-qPCR for CBS expression analysis, LC-MS metabolite profiling of homocysteine and cysteine, H?S production assays, glutathione measurement, and ROS detection. Cell proliferation, caspase activity, and RNA-seq experiments can be employed to investigate downstream effects. This tool is suitable for drug screening and pathway interrogation. For further information, please contact Ascent Research.
