The DTNB Knockout NCI-H1975 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the DTNB gene in the NCI-H1975 lung adenocarcinoma cell line. This loss-of-function model enables investigation of dystrobrevin beta-dependent processes without imposing clonal selection, preserving the inherent heterogeneity of the tumor cell population. The polyclonal format provides a robust system for studying gene function in a context that more closely mimics the genetic diversity observed in patient tumors, facilitating drug sensitivity and signaling studies.
NCI-H1975 is a human non-small cell lung cancer cell line isolated from a non-smoking female with lung adenocarcinoma. These cells harbor dual EGFR mutations (L858R/T790M), which confer resistance to first-generation tyrosine kinase inhibitors. As a model of acquired EGFR inhibitor resistance, NCI-H1975 is widely used to explore mechanisms driving treatment failure and to screen next-generation targeted therapies. The epithelial origin and metastatic potential of this line further support its utility in invasion and cytoskeletal dynamics research.
The DTNB gene encodes dystrobrevin beta, a key structural adaptor of the dystrophin-glycoprotein complex. This complex links the actin cytoskeleton to the extracellular matrix through interactions with dystrophin (DMD), utrophin (UTRN), ??- and ??-dystrobrevin (DTNA, DTNB), syntrophins (SNTA1, SNTB1), and dystroglycan (DAG1). DTNB is regulated by MEF2 transcription factors, SP1, mechanical stress, and EGFR signaling, and it coordinates downstream activation of Rac1, Cdc42, FAK, ERK1/2, and AKT to modulate actin polymerization and cell adhesion. By scaffolding these components, DTNB maintains membrane stability and integrates adhesive cues with mitogenic signaling.
Disruption of DTNB in NCI-H1975 cells compromises the integrity of the dystrophin-glycoprotein complex, leading to altered membrane stability and adhesion signaling. This perturbation is predicted to impair cell migration and invasion, while potentially modulating EGFR-dependent downstream pathways. Given the EGFR T790M/L858R background, DTNB knockout may influence sensitivity to EGFR TKIs such as gefitinib and osimertinib, offering a platform to dissect cross-talk between cytoskeletal organization and drug resistance. The model thus addresses gaps in understanding how structural proteins contribute to therapeutic responses in lung adenocarcinoma.
Typical applications include probing EGFR TKI resistance mechanisms via phospho-EGFR/ERK analysis and drug sensitivity assays, assessing metastatic behavior using Transwell invasion and wound healing assays, and examining cytoskeletal reorganization through immunofluorescence and Rho GTPase activation assays. Co-immunoprecipitation and Western blotting enable validation of DTNB interactions with DMD, DAG1, and other complex members, while RT-qPCR quantifies transcriptional changes. This product is suitable for target validation, adhesion signaling studies, and high-throughput drug screening. For additional information, please contact Ascent Research.
