The HPDL Knockout NCI-H1975 Polyclonal Cells constitute a CRISPR/Cas9-edited polyclonal knockout cell population engineered to disrupt the HPDL gene in the NCI-H1975 human lung adenocarcinoma epithelial cell line. This gene-edited model is designed for researchers studying tyrosine catabolism, redox homeostasis, and metabolic vulnerabilities in EGFR-mutant non-small cell lung carcinoma. The polyclonal format preserves the genetic heterogeneity arising from CRISPR/Cas9-mediated gene disruption without clonal selection, providing a population-level representation of HPDL loss-of-function rather than an isolated monoclonal derivative. As such, it is well-suited for bulk assays that demand biological replicates and reproducible population responses, including metabolomic profiling, oxidative stress measurements, and drug sensitivity screens.
The host cell line, NCI-H1975, is an established model of lung adenocarcinoma harboring the activating EGFR L858R mutation and the secondary T790M gatekeeper mutation, which confer oncogenic signaling and acquired resistance to first-generation EGFR tyrosine kinase inhibitors. This cell line is widely employed to explore mechanisms of EGFR inhibitor resistance, metabolic reprogramming, and tumor cell adaptation to targeted therapies. Its epithelial origin and mutant EGFR background provide a physiologically relevant context for dissecting how metabolic enzyme alterations influence cancer cell fitness, particularly under conditions of nutrient stress or pharmacologic challenge.
HPDL encodes a 4-hydroxyphenylpyruvate dioxygenase-like protein that mediates the conversion of 4-hydroxyphenylpyruvate to homogentisate, a critical step in the tyrosine degradation pathway. This reaction is functionally dependent on mitochondrial import machinery and likely requires Fe2+ as a cofactor. HPDL acts downstream of key regulators such as HIF1A, which is induced by hypoxia, and PPARG, a lipid-sensing nuclear receptor, and its activity is modulated by dietary tyrosine availability. The homogentisate produced by HPDL is subsequently processed by GSTZ1 and FAH to yield fumarate and acetoacetate, linking tyrosine catabolism to the tricarboxylic acid cycle and ketone body production. Disruption of HPDL abolishes this enzymatic activity, leading to accumulation of 4-hydroxyphenylpyruvate and other upstream metabolites, together with elevation of reactive oxygen species, thereby perturbing cellular redox balance.
In the context of NCI-H1975 cells, loss of HPDL is predicted to exacerbate metabolic stress and alter the redox environment that supports EGFR-driven proliferation. Because these cells rely on sustained oncogenic signaling and may experience basal oxidative stress, HPDL knockout can uncover vulnerabilities that sensitize them to further metabolic perturbation or therapeutic intervention. This model is thus a powerful tool for investigating the intersection between tyrosine catabolism and EGFR-mutant lung adenocarcinoma biology, potentially revealing new nodes for therapeutic targeting in tumors that exhibit altered amino acid metabolism or heightened dependence on redox regulatory pathways.
This product is applicable to a broad range of research applications, including but not limited to: elucidation of tyrosine catabolic roles in cancer metabolism; assessment of EGFR-mutant NSCLC metabolic liabilities; evaluation of HPDL loss on oxidative stress responses and drug sensitivity; and analysis of neuroprotective gene function within a lung cancer context. Representative assays include western blotting, RT-qPCR, LC-MS-based metabolite profiling, ROS measurement, cell viability and proliferation assays, EGFR signaling phospho-analysis, clonogenic survival assays, and drug sensitivity screens. This polyclonal knockout cell population offers a robust platform for functional genomics and drug discovery studies. For further information or to discuss this model, please contact Ascent Research.
