The HEXB Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the HEXB gene in NCI-H1975 human lung adenocarcinoma epithelial cells. This ready-to-use knockout model provides a genetically heterogeneous cell pool with targeted gene disruption, eliminating single-cell cloning while enabling functional studies of HEXB-dependent processes. The polyclonal format preserves population variability, making it suitable for unbiased screening and pathway analysis in a physiologically relevant cancer cell background.
The NCI-H1975 cell line was derived from a metastatic pleural effusion of a female patient with non-small cell lung carcinoma and harbors an EGFR L858R mutation. These epithelial cells are sensitive to EGFR tyrosine kinase inhibitors, serving as a well-characterized model for EGFR-driven oncogenic signaling and drug resistance. Integrating HEXB knockout into this background enables investigation of lysosomal function in EGFR-mutant lung adenocarcinoma, where aberrant lysosomal activity influences tumor progression and therapy response.
HEXB encodes the beta subunit of lysosomal beta-hexosaminidase, forming heterodimeric Hex A (with HEXA) and homodimeric Hex B. These isoenzymes hydrolyze terminal N-acetyl-D-hexosamine residues from GM2 gangliosides and other glycoconjugates in glycosphingolipid degradation. Hex A, activated by GM2A, cleaves GM2 into GM3, further processed by sialidase to lactosylceramide, glucosylceramide, and ceramide. Beyond degradation, HEXB is regulated by TFEB, MITF, and TFE3 downstream of mTORC1, and associates with LAMP1 and LAMP2, linking to lysosomal positioning and autophagy.
Disruption of HEXB in NCI-H1975 cells leads to loss of Hex A and Hex B activities, causing GM2 ganglioside accumulation in enlarged lysosomes. This lysosomal storage phenotype accompanies autophagy dysfunction and altered lysosomal signaling. In the EGFR L858R-mutant context, lysosomal sequestration and mTORC1 regulation may affect EGFR turnover, downstream signaling, and therapeutic sensitivity. Thus, the HEXB knockout provides a unique tool to explore how lysosomal homeostasis impacts oncogenic signaling, metabolic adaptation, and autophagy-dependent survival in cancer cells.
These polyclonal knockout cells support diverse applications: modeling GM2 gangliosidosis and Sandhoff disease, investigating glycosphingolipid metabolism in lung cancer, and studying lysosome-autophagy crosstalk. Validation can be performed via hexosaminidase enzymatic assays, HPLC/Mass spectrometry for GM2, and immunofluorescence for LAMP1/2 and GM2. Additional assays include autophagy flux analysis, electron microscopy of lysosomal morphology, and EGFR inhibitor sensitivity testing. The model enables pharmacological screening of chaperones, enzyme replacement strategies, and evaluation of GM2 accumulation effects on tumor cell proliferation and therapy response. For more information, contact Ascent Research.
