The EBAG9 Knockout NCI-H1975 Polyclonal Cells are a polyclonal CRISPR/Cas9-edited human lung adenocarcinoma cell population with targeted disruption of the EBAG9 gene (also known as RCAS1). This loss-of-function model enables the study of EBAG9-mediated immune evasion and apoptosis regulation in a non-small cell lung cancer (NSCLC) context.
The NCI-H1975 host cell line is derived from the pleural effusion of a nonsmoking female patient with lung adenocarcinoma. It harbors activating EGFR L858R and resistance T790M mutations, making it a widely used model for EGFR-driven NSCLC. This genetic background provides a relevant system for investigating tumor-intrinsic signaling and immune interactions.
EBAG9 (estrogen receptor-binding fragment-associated gene 9) encodes a tumor-associated antigen that functions as a checkpoint molecule. Its expression is upregulated by estrogen receptor signaling and the transcription factor NF-??B. The EBAG9 protein, in conjunction with the interacting partner Galectin-3 (LGALS3), binds to a putative immune receptor on cytotoxic lymphocytes. This interaction promotes mitochondrial cytochrome c release and activation of the caspase cascade, culminating in caspase-9 and caspase-3-mediated apoptosis of the immune effector cells. In parallel, EBAG9 amplifies intracellular survival signals via the PI3K/Akt pathway, which converges on NF-??B to repress the expression of pro-apoptotic genes and inhibit the intrinsic apoptotic machinery. Consequently, EBAG9 operates downstream of EGFR and hormone receptors to synchronize immune evasion with tumor cell viability.
In the NCI-H1975 cell line, which is addicted to mutant EGFR signaling, knockout of EBAG9 is expected to disrupt this immune?privileged state. The removal of EBAG9 function prevents the induction of apoptosis in co?cultured T cells and simultaneously sensitizes the lung adenocarcinoma cells to intrinsic apoptosis, likely through relief of Akt?NF???B?mediated survival programs. This polyclonal knockout population therefore offers a physiologically relevant platform to study how EGFR?driven NSCLC subverts antitumor immunity, and to evaluate the therapeutic potential of combining EGFR inhibitors with strategies that restore immune cell activity.
The EBAG9 Knockout NCI-H1975 Polyclonal Cells are suitable for a variety of experimental applications. Flow cytometry using EBAG9?specific antibodies can confirm the loss of protein expression. Co?culture cytotoxicity assays, such as with CAR?T cells or patient?derived lymphocytes, directly measure the restoration of immune?mediated killing. Annexin V?based apoptosis detection and Western blotting for cleaved caspase?3 and caspase?9 allow quantification of the intrinsic apoptotic response. RT?qPCR can be used to profile changes in downstream target genes like those encoding caspases and Bcl?2 family members. These cells also serve as an appropriate model for xenograft studies to investigate immune cell infiltration and tumor progression in vivo. For further details, please contact Ascent Research.
