The GRAMD1B Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the GRAMD1B gene in NCI-H1975 cells. This loss-of-function model facilitates the study of GRAMD1B-dependent processes in lung adenocarcinoma. The polyclonal product arises from CRISPR/Cas9-mediated gene disruption without clonal selection, providing a population-level knockout suitable for functional analyses.
NCI-H1975 is a human lung adenocarcinoma cell line derived from a female non-smoker. It harbors EGFR L858R and T790M mutations, modeling non-small cell lung cancer with acquired tyrosine kinase inhibitor resistance. This cell line is extensively used to investigate EGFR-driven oncogenic signaling and therapeutic vulnerabilities.
GRAMD1B encodes a sterol transfer protein at ER-PM contact sites that senses cholesterol levels and mediates non-vesicular cholesterol transport. It interacts with VAPA, VAPB, OSBP, and PtdIns(4,5)P2 to regulate lipid exchange. Cellular cholesterol and mTOR signaling act upstream, while GRAMD1B activity influences membrane cholesterol content, AKT/mTOR pathway activity, and autophagy. GRAMD1B is implicated in autophagosome formation, modulating LC3 processing and autophagy-related proteins such as ATG5 and ATG12. Through its role in lipid redistribution, GRAMD1B may indirectly impact EGFR-dependent signaling cascades.
In the NCI-H1975 EGFR-mutant background, GRAMD1B knockout likely disrupts cholesterol distribution at ER-PM junctions, altering lipid raft-mediated receptor clustering and downstream AKT/mTOR signaling. This model allows investigation of how cholesterol transfer proteins modulate oncogenic pathways and autophagy in NSCLC. It can be used to explore whether GRAMD1B loss sensitizes cells to EGFR inhibitors or lipid metabolism-targeted interventions.
Applications include analysis of cholesterol trafficking and autophagy regulation via western blot (LC3, p62, AKT), filipin staining, RT-qPCR, and immunofluorescence. The model supports cell proliferation, migration, and drug sensitivity assays with EGFR inhibitors or autophagy modulators. By linking lipid transfer to oncogenic signaling, this knockout system aids in dissecting metabolic vulnerabilities in lung adenocarcinoma. For further information, please contact Ascent Research.
