The HTRA1 Knockout NCI-H1975 Polyclonal Cells constitute a CRISPR/Cas9-edited polyclonal knockout population derived from the NCI-H1975 human lung adenocarcinoma cell line. This model features targeted disruption of the HTRA1 gene, resulting in loss of tumor suppressor function. The polyclonal format provides a heterogeneous knockout background suitable for functional studies. This product is intended for in vitro research applications in cancer biology and signal transduction.
The host NCI-H1975 cell line was established from pleural effusion of a female non-small cell lung cancer patient and carries activating EGFR L858R and T790M mutations. These mutations confer sensitivity to EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib, and the T790M mutation often mediates acquired resistance. NCI-H1975 is widely employed as a model for investigating EGFR signaling, drug response, and resistance mechanisms in lung adenocarcinoma.
HTRA1 encodes a secreted serine protease that suppresses TGF-?? signaling by cleaving TGF-??1 ligands and shedding the ectodomain of the TGF-?? type II receptor (TGFBR2). This activity reduces SMAD2/3 phosphorylation and downstream transcriptional responses. HTRA1 also degrades extracellular matrix components including fibronectin, decorin, and biglycan, linking its function to ECM remodeling. The protease is regulated by p53 and is frequently silenced in cancer. Knockout of HTRA1 in NCI-H1975 cells is known to elevate TGF-?? pathway activity, promoting epithelial-mesenchymal transition (EMT), invasion, and apoptosis resistance.
In the NCI-H1975 background with EGFR L858R/T790M, HTRA1 knockout provides a valuable tool to study the interplay between TGF-?? signaling and EGFR-targeted therapy resistance. Enhanced TGF-?? activity resulting from HTRA1 loss may drive phenotypic plasticity and contribute to drug-tolerant persister states, making this model relevant for investigating mechanisms of gefitinib resistance and testing combination treatment strategies.
This knockout model supports a range of experimental approaches, including western blotting, RT-qPCR, TGF-?? ELISA, and luciferase reporter assays to monitor pathway activity. Functional assays such as cell proliferation, migration/invasion, and apoptosis analysis can characterize the cellular consequences of HTRA1 disruption. Co-immunoprecipitation enables interaction studies with ECM proteins or receptors. Drug sensitivity testing with EGFR TKIs is particularly informative. For inquiries, contact Ascent Research.
