The IDH3B Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human NCI-H1975 lung adenocarcinoma cell line. This product provides a heterogeneous pool of cells carrying targeted disruption of the IDH3B gene, offering a loss-of-function model for studying IDH3 function in a non-small cell lung cancer (NSCLC) context free of clonal selection artifacts.
The parental NCI-H1975 line is a widely used NSCLC model harboring EGFR L858R and T790M mutations, which drive constitutive oncogenic signaling and metabolic reprogramming. These cells rely on mitochondrial metabolism and glutamine utilization, making them especially relevant for investigating TCA cycle dynamics and their role in drug resistance.
IDH3B encodes the ??-subunit of the mitochondrial NAD+-dependent isocitrate dehydrogenase complex, catalyzing the oxidative decarboxylation of isocitrate to ??-ketoglutarate (??-KG) with concomitant NADH generation. Transcription is controlled by PPARGC1A, NRF1, and TFAM. IDH3B functions within the TCA cycle and interacts with IDH3A, IDH3G, citrate synthase, and ATP citrate lyase. Its activity supplies ??-KG for TET dioxygenases and influences HIF1A stability via prolyl hydroxylases. Knockout therefore disrupts ??-KG-dependent epigenetic regulation, the NADH/NAD+ redox equilibrium, and flux through key TCA intermediates including citrate, succinyl-CoA, succinate, fumarate, and malate.
In the EGFR-mutant NCI-H1975 background, IDH3B disruption alters mitochondrial oxidative metabolism, reducing ??-KG production and shifting the NADH/NAD+ ratio. These changes modulate HIF1A activity and TET-mediated DNA demethylation, potentially impacting gene expression and metabolic adaptation. The model enables dissection of how TCA cycle dysfunction contributes to NSCLC proliferation, survival, and therapeutic response to EGFR inhibitors, and provides a tool to identify metabolic vulnerabilities linked to IDH3 loss.
Applications include metabolic flux analysis with Seahorse or LC-MS, glutamine metabolism studies, proliferation and apoptosis assays, RNA-seq, and targeted metabolomics. These polyclonal cells are suitable for Western blot and RT-qPCR confirmation of IDH3B ablation and downstream effectors. They support research into mitochondrial disorders, cancer metabolic reprogramming, and NSCLC drug resistance mechanisms. For further details, please contact Ascent Research.
