The INPPL1 Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population derived from the NCI-H1975 human lung adenocarcinoma epithelial cell line, designed with disruption of the INPPL1 gene. This loss-of-function model ablates expression of the lipid phosphatase SHIP2, a key attenuator of phosphoinositide 3-kinase (PI3K) signaling, providing a versatile tool for examining cellular responses in a heterogeneous knockout background.
The parental NCI-H1975 cell line was established from the lung adenocarcinoma of a non-smoking female and harbors activating EGFR mutations (L858R and T790M) together with a TP53 R273H loss-of-function mutation. These adherent epithelial cells are a well-characterized model for EGFR-mutant non-small cell lung cancer (NSCLC) and are extensively used to study oncogenic signaling, tumor cell biology, and mechanisms of acquired resistance to EGFR tyrosine kinase inhibitors (TKIs).
INPPL1 encodes SHIP2, a 5??-inositol phosphatase that hydrolyzes PI3K-generated PIP3 to PI(3,4)P2, directly opposing AKT activation. Upstream regulators include EGF, insulin, PDGF, Src, and Abl kinases. By diminishing PIP3 levels, SHIP2 reduces phosphorylation of AKT, resulting in GSK3?? de-repression, mTORC1 inhibition, and sustained FOXO activity. SHIP2 also scaffolds complexes containing Grb2, Shc, and Crk, and interacts with p130Cas and filamin to modulate actin dynamics and cell motility.
In NCI-H1975 cells, which possess constitutively active EGFR, INPPL1 disruption is predicted to increase PIP3 levels and amplify PI3K/AKT-driven processes. This system enables analysis of SHIP2-mediated feedback regulation of EGFR output and its impact on cell proliferation, survival, and motility. The knockout also offers a platform to assess changes in drug sensitivity to EGFR TKIs and PI3K inhibitors, contributing to the study of adaptive resistance mechanisms.
Applications include functional studies of SHIP2 in NSCLC, western blotting for phospho-AKT(S473) and phospho-S6, RT-qPCR validation, MTT and drug dose-response assays, transwell migration and invasion, Annexin V apoptosis, colony formation, and F-actin immunofluorescence. Co-immunoprecipitation and phospho-kinase arrays can map altered signaling networks. For further details, contact Ascent Research.
