The CBR4 Knockout NCI-H1975 Polyclonal Cells product comprises a polyclonal population of human NCI-H1975 cells in which the CBR4 gene has been disrupted by CRISPR/Cas9. This polyclonal knockout pool enables functional studies of carbonyl reductase 4 activity without the artifacts of single-cell cloning. It is well-suited for population-level analyses of gene function, drug responses, and pathway activity in lung adenocarcinoma research.
The NCI-H1975 host cell line, derived from a non-smoking female patient with lung adenocarcinoma, harbors characteristic EGFR mutations (L858R and T790M) and a TP53 mutation. As an adherent epithelial model of non-small cell lung carcinoma (NSCLC), it is widely used to investigate oncogenic signaling, acquired resistance to EGFR tyrosine kinase inhibitors, and the role of metabolic pathways in cancer cell survival.
CBR4 encodes a NADPH-dependent carbonyl reductase belonging to the short-chain dehydrogenase/reductase family. It reduces a broad spectrum of carbonyl-containing substrates, including xenobiotics and endogenous reactive aldehydes such as 4-hydroxynonenal (4-HNE), thereby converting them to less toxic alcohols. This enzymatic activity protects cells from oxidative damage by decreasing lipid peroxidation adducts and protein carbonylation. CBR4 expression is transcriptionally upregulated by NRF2 and regulated by AhR under oxidative stress. Within the NRF2-KEAP1 antioxidant pathway, CBR4 functions as a downstream effector that mitigates carbonyl stress, linking redox homeostasis to cellular detoxification.
In the NCI-H1975 background, disruption of CBR4 is anticipated to compromise the detoxification of reactive carbonyl species, increasing sensitivity to oxidative stressors and carbonyl-inducing chemotherapeutics. Given the interplay between oxidative stress and EGFR-driven oncogenic signaling, this polyclonal knockout model provides a relevant system to explore how carbonyl metabolism influences drug resistance and tumor cell survival in TKI-resistant NSCLC with EGFR L858R/T790M mutations.
Researchers can employ this CBR4 knockout polyclonal cell population for diverse assays, including cell viability under oxidative challenge (e.g., H2O2, 4-HNE), protein carbonylation detection, TBARS-based lipid peroxidation measurement, and RT-qPCR profiling of NRF2 target genes. Additional applications include Western blotting for CBR4 and oxidative stress markers, Annexin V/PI apoptosis assays, ROS detection with DCFDA, and colony formation to assess long-term proliferation. These cells are also suitable for drug sensitivity screens and studies of metabolic detoxification pathways. For further details or technical assistance, please contact Ascent Research.
