The GSK3A Knockout NCI-H1975 Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal knockout population in which the GSK3A gene has been disrupted in the NCI-H1975 human lung adenocarcinoma cell line. This product provides a loss-of-function model system for investigating the cellular and biochemical roles of glycogen synthase kinase 3 alpha. The polyclonal format presents a heterogeneous mixture of gene-edited cells, enabling the study of GSK3A-dependent phenotypes in a context that captures the genetic variability inherent to pooled knockout populations. This cell product is designed for advanced research applications in cancer biology, signal transduction, and targeted therapy resistance.
NCI-H1975 is an adherent epithelial cell line originally derived from a female patient with lung adenocarcinoma. The cell line harbors well-characterized EGFR L858R and T790M mutations, making it a widely used model for EGFR-mutant non-small cell lung cancer (NSCLC). These mutations confer sensitivity to first- and second-generation tyrosine kinase inhibitors (TKIs) while also predisposing cells to acquired resistance. Consequently, NCI-H1975 cells are employed extensively to dissect mechanisms of TKI resistance, oncogenic signaling, and tumor cell adaptation.
GSK3A encodes a constitutively active serine/threonine kinase that acts as a central node in multiple signaling pathways. In the absence of Wnt ligands, GSK3A is part of the ??-catenin destruction complex with Axin1, APC, and DVL2, where it phosphorylates CTNNB1 (??-catenin) to promote its proteasomal degradation. Pathway activation by Wnt3A or insulin/PI3K/AKT signaling results in inhibitory phosphorylation of GSK3A by AKT1, leading to ??-catenin stabilization and TCF7L2-mediated transcription of c-Myc and CCND1 (Cyclin D1). GSK3A also phosphorylates GYS1, MCL1, tau (MAPT), CREB1, and NFATc1, thus influencing glycogen metabolism, apoptosis, and gene expression. Upstream regulators include insulin receptor, EGF, PDGF, PKA, and PKC, while interacting factors encompass FRAT1 and PP2A.
In NCI-H1975 lung adenocarcinoma cells expressing EGFR L858R/T790M, GSK3A knockout is likely to perturb the balance of oncogenic signaling. AKT1-mediated inhibition of GSK3A lies downstream of EGFR/PI3K; disrupting GSK3A may simulate or amplify AKT pathway output, potentially leading to increased ??-catenin stability, elevated c-Myc and CCND1 expression, and altered apoptotic sensitivity. This model enables precise investigation of whether GSK3A loss cooperates with pre-existing EGFR mutations to influence TKI resistance, cell survival, or tumor progression.
Typical research applications include ??-catenin/TCF luciferase reporter assays, western blotting for GSK3A, ??-catenin, c-Myc, and phospho-substrates, and RT-qPCR for downstream targets. Functional assays span cell proliferation (MTT), apoptosis (Annexin V flow cytometry), migration/invasion (Boyden chamber), and drug sensitivity profiling with EGFR TKIs such as erlotinib and osimertinib. The cell product is also suited for screening GSK3A-dependent substrates and studying insulin/Wnt crosstalk in NSCLC. For further information, contact Ascent Research.
