This product consists of a CRISPR/Cas9-edited polyclonal knockout cell population derived from the NCI-H1975 human non-small cell lung cancer (NSCLC) cell line, engineered to disrupt the CCDC85C gene (DIPA). The polyclonal format provides a heterogeneous pool of cells carrying various loss-of-function mutations, enabling robust assessment of CCDC85C-dependent effects without the constraints of single-cell clonal variation. This model serves as a versatile tool for investigating the negative regulation of Notch signaling in a clinically relevant lung adenocarcinoma background.
The parental NCI-H1975 cell line was established from the pleural effusion of a female never-smoker with lung adenocarcinoma and harbors endogenous EGFR L858R and T790M mutations, the latter conferring resistance to first- and second-generation EGFR tyrosine kinase inhibitors (TKIs). As a well-characterized NSCLC model for acquired EGFR TKI resistance, NCI-H1975 cells exhibit constitutive EGFR pathway activation and are widely employed to study resistance mechanisms and therapeutic vulnerabilities in oncogene-driven lung cancer.
CCDC85C encodes DIPA, a negative regulator of the Notch signaling pathway. Mechanistically, CCDC85C interacts directly with Delta-like ligands, including DLL1 and DLL4, preventing their binding to Notch receptors (NOTCH1?C4) and thereby suppressing the ??-secretase-mediated release of the Notch intracellular domain (NICD). This blocks NICD translocation to the nucleus, where it would otherwise form a transcriptional activation complex with CSL/RBPJ and MAML co-activators to induce target genes such as HES1 and HEY1. Consequently, CCDC85C acts upstream of core Notch pathway components, and its disruption is predicted to relieve inhibition, leading to enhanced transcription of HES and HEY family repressors.
In the context of NCI-H1975 cells, Notch signaling intersects with EGFR-driven oncogenic programs, influencing cell fate decisions, epithelial-to-mesenchymal transition, and drug sensitivity. Loss of CCDC85C-mediated Notch suppression may alter the balance between proliferation and differentiation, potentially modulating TKI resistance phenotypes. This polyclonal knockout model enables researchers to dissect how derepression of Notch signaling affects the malignant properties of EGFR-mutant adenocarcinoma cells, providing insights into pathway crosstalk and adaptive resistance mechanisms.
Researchers can employ these polyclonal CCDC85C knockout cells in a range of experimental systems, including Notch luciferase reporter assays to quantify pathway activity, co-immunoprecipitation to confirm disruption of CCDC85C?CDLL interactions, western blotting or RT-qPCR for HES1/HEY1 expression changes, and functional assays such as MTT proliferation, transwell migration, and EGFR inhibitor sensitivity testing. The heterogeneous knockout population is particularly suited for pooled screening and phenotypic analyses where averaging over multiple genotypes yields biologically relevant insights. For ordering information, technical specifications, or batch-specific data, please contact Ascent Research.
