The ITGB8 Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the NCI-H1975 human lung adenocarcinoma cell line, designed to disrupt the ITGB8 gene. This product provides a heterogeneous pool of cells carrying targeted gene disruptions, offering a versatile loss-of-function model for studying integrin beta-8 biology. The polyclonal format eliminates clonal selection artifacts while maintaining robust knockout across the population, making it ideal for functional studies where monoclonal isolation is not required. The cells are produced using CRISPR/Cas9 technology to introduce targeted modifications without a defined editing pattern, ensuring broad utility in investigating ITGB8-dependent mechanisms.
The host cell line NCI-H1975 is a widely used model of non-small cell lung cancer (NSCLC), originally derived from a non-smoking female patient with lung adenocarcinoma. These epithelial cells harbor the EGFR L858R/T790M double mutation, conferring sensitivity to first-generation EGFR tyrosine kinase inhibitors but also predisposing to acquired resistance. NCI-H1975 cells exhibit key characteristics of advanced NSCLC, including deregulated proliferation, enhanced survival signaling, and metastatic potential. Their genetic background makes them particularly relevant for studying oncogenic signaling networks and evaluating therapeutic strategies against T790M-mediated resistance.
ITGB8 encodes the integrin beta-8 subunit, which pairs exclusively with integrin alpha-V (ITGAV) to form the alpha-V/beta-8 heterodimer. This integrin is a key activator of latent transforming growth factor-beta (TGF-beta) by binding to the latency-associated peptide (LAP) of the TGF-beta1 complex and inducing a conformational change that releases active TGF-beta1. Active TGF-beta1 then engages TGF-beta receptors (TGFBR1/2), leading to phosphorylation of SMAD2/3, which form complexes with SMAD4 and translocate to the nucleus to regulate target gene transcription. Downstream effectors include SMAD7 (inhibitory feedback), CTGF, and matrix metalloproteinases (MMPs), as well as mesenchymal markers such as Vimentin and N-cadherin. ITGB8 expression is controlled by transcription factors SP1 and ETS1, and is upregulated by TGF-beta1 itself and EGFR signaling, creating a positive feedback loop. The integrin also interacts with extracellular matrix components vitronectin and fibronectin, linking cell adhesion to TGF-beta activation.
In the context of NCI-H1975 NSCLC cells, ITGB8-mediated TGF-beta activation drives epithelial-mesenchymal transition (EMT), a process critical for tumor invasion and metastasis. Knockout of ITGB8 disrupts this signaling axis, potentially reducing the activation of SMAD2/3 and attenuating the expression of EMT markers and MMPs. This model is especially valuable because NCI-H1975 cells harbor EGFR mutations that can crosstalk with TGF-beta pathways to promote aggressive tumor behavior and immunosuppression within the microenvironment. By ablating ITGB8, researchers can examine how integrin-dependent TGF-beta release contributes to drug resistance, particularly to EGFR inhibitors, and explore whether targeting this axis enhances therapeutic responses.
This polyclonal knockout cell population is ideal for a range of experimental applications, including investigation of ITGB8??s role in lung cancer progression, TGF-beta activation mechanisms, and EMT. Representative assays include Western blotting for ITGB8 and phosphorylated SMAD2, RT-qPCR for EMT markers (e.g., Vimentin, N-cadherin), and transwell migration/invasion assays to assess metastatic potential. TGF-beta bioassays using luciferase reporters can quantify active TGF-beta levels, while cell adhesion assays on vitronectin or fibronectin evaluate integrin function. Immunofluorescence and flow cytometry enable visualization and quantification of surface ITGB8, and MTT proliferation assays or drug sensitivity tests with EGFR inhibitors can be used to study growth and resistance. For further details, please contact Ascent Research.
