The CBR1 Knockout SK-HEP-1 Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal population originating from the SK-HEP-1 hepatocellular carcinoma line, featuring disruption of the CBR1 gene. This heterogeneous pool disrupts CBR1 protein expression, enabling robust loss-of-function studies in a mixed genetic background. These cells are tailored for studying carbonyl reductase activity, drug detoxification pathways, and liver cancer signaling.
The SK-HEP-1 cell line was originally isolated from ascitic fluid of a hepatocellular carcinoma patient and displays both endothelial and epithelial characteristics, providing a versatile model for liver cancer research. It is widely used to examine hepatocellular carcinoma pathogenesis, chemotherapeutic drug responses, and xenobiotic metabolism, recapitulating key aspects of the hepatic tumor microenvironment and intracellular detoxification processes.
CBR1 encodes a monomeric NADPH-dependent carbonyl reductase that reduces a broad range of substrates, including anthracycline chemotherapeutics (e.g., doxorubicin), prostaglandin H2, and cytotoxic lipid peroxidation products like 4-hydroxynonenal. Transcription of CBR1 is activated by the KEAP1?CNrf2 antioxidant response pathway: under oxidative stress, Nrf2 dissociates from KEAP1, translocates to the nucleus, and induces expression of CBR1 along with other detoxifying genes. Additional regulation occurs through PPAR?? and the aryl hydrocarbon receptor (AhR). In arachidonic acid metabolism, CBR1 catalyzes the conversion of prostaglandin H2 to prostaglandin F2??, connecting it to inflammatory processes. The enzyme partners with NADPH and may functionally interact with cytochrome P450 enzymes and other carbonyl reductases to modulate cellular redox balance. By reducing doxorubicin to inactive metabolites, CBR1 directly contributes to chemoresistance, whereas its detoxification of 4-hydroxynonenal mitigates oxidative stress-induced apoptosis.
In the context of hepatocellular carcinoma, CBR1 is often overexpressed and linked to intrinsic doxorubicin resistance. Disruption of CBR1 in SK-HEP-1 cells eliminates this protective mechanism, markedly sensitizing them to doxorubicin-induced cytotoxicity and oxidative damage. This knockout model thus serves as a powerful tool for dissecting the molecular pathways underlying drug resistance and for testing combinatorial therapies that aim to resensitize liver cancer cells. Moreover, the endothelial-like properties of SK-HEP-1 cells allow for the investigation of potential crosstalk between carbonyl reductase activity and angiogenic or adhesion signaling pathways in the tumor microenvironment.
These polyclonal CBR1 knockout cells are well-suited for a variety of functional assays, including doxorubicin IC50 determination, apoptosis and viability analyses, and direct measurement of carbonyl reductase activity using specific substrates. Transcriptomic and metabolomic profiling via RNA-seq and mass spectrometry can reveal global adaptations to CBR1 loss, while Western blotting and RT-qPCR verify knockout efficiency and monitor compensatory regulation of related reductases and Nrf2 target genes. For additional details or to place an order, please contact Ascent Research.
