The CBS Knockout NCI-H1299 Polyclonal Cells are a CRISPR/Cas9-mediated polyclonal knockout cell population generated from the NCI-H1299 non-small cell lung carcinoma line. This mixed cell pool carries targeted disruption of the CBS gene, providing a loss-of-function model for functional studies in a physiologically relevant cancer context.
The NCI-H1299 cell line originates from a lymph node metastasis of a lung adenocarcinoma and is widely established as a model for metastatic non-small cell lung cancer (NSCLC). Notably, these cells are p53-null, which contributes to their aggressive and invasive properties and makes them particularly valuable for studying oncogenic signaling and drug responses in a p53-deficient context. The epithelial morphology and metastatic origin of NCI-H1299 cells provide a suitable background for evaluating the role of CBS in lung cancer progression and metastasis.
CBS encodes cystathionine-??-synthase, a pyridoxal-5??-phosphate-dependent enzyme catalyzing condensation of homocysteine and serine to form cystathionine, the committed step of the transsulfuration pathway. This link between methionine cycle and cysteine biosynthesis also generates hydrogen sulfide (H2S). CBS transcription is regulated by SP1, NF-??B, NRF2, and HIF-1??, and its activity allosterically modulated by S-adenosylmethionine (SAM). Downstream, cystathionine is converted by cystathionine-??-lyase (CTH) to cysteine, feeding glutathione synthesis or protein persulfidation. CBS-derived H2S modifies targets like NF-??B and Keap1 via persulfidation, influencing redox and inflammatory signaling.
In the context of NCI-H1299 lung cancer cells, CBS knockout disrupts the transsulfuration pathway, impairing cysteine and glutathione synthesis and reducing H2S production. Given the p53-null status of these cells, which inherently alters redox balance and survival signaling, CBS loss may further sensitize cells to oxidative stress or alter their metastatic potential. This model is particularly relevant for dissecting the role of H2S in NSCLC biology, including its effects on cell proliferation, migration, and drug resistance. Moreover, because CBS is linked to homocystinuria and cardiovascular disease, this knockout model can be used to explore CBS-associated metabolic vulnerabilities in cancer.
Typical applications include functional studies of CBS in lung cancer, H2S signaling investigation, metabolic flux analysis of methionine/transsulfuration pathways, and redox homeostasis assessment. Compatible assays include Western blotting for CBS and CTH, RT-qPCR, MTS/MTT proliferation, Transwell migration, fluorimetric H2S detection, glutathione quantification, ROS measurement, Seahorse metabolic analysis, and PCR-based genotyping (T7E1 or TIDE). This polyclonal population enables CBS inhibitor screening and interrogation of sulfur metabolism-oncogenic signaling crosstalk. For details, contact Ascent Research.
