The HRAS Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the HRAS gene. This loss-of-function model provides a pooled population of edited cells, minimizing clonal artifacts and enabling robust investigation of HRAS-dependent signaling in a lung adenocarcinoma context. Suitable for assays requiring quantitative pathway analysis, the polyclonal format ensures representative assessment of gene disruption effects without the bias of clonal selection.
The parental NCI-H1975 cell line is an epithelial lung adenocarcinoma model carrying activating EGFR mutations L858R and T790M. These mutations drive constitutive tyrosine kinase signaling and are linked to acquired resistance to first-line EGFR inhibitors. Widely used in non-small cell lung cancer research, the line’s dependence on downstream RAS?CMAPK signaling makes it an ideal platform for studying oncogenic EGFR-to-RAS circuitry.
HRAS encodes a small GTPase that functions as a binary switch, toggling between inactive GDP-bound and active GTP-bound conformations. In the NCI-H1975 background, oncogenic EGFR promotes HRAS activation through adaptor proteins GRB2 and SOS1, leading to GTP loading. Active HRAS stimulates multiple effector cascades, including the RAF1?CMEK1/2?CERK1/2 kinase module and the PI3K?CAKT survival pathway. Additionally, it engages RalGDS and Rac/Rho pathways. The switch is regulated by exchange factors such as SOS1 and RASGRP, and GTPase-activating proteins like NF1. Thus, HRAS integrates growth factor signals to control proliferation and survival.
Disrupting HRAS in the EGFR-mutant NCI-H1975 line creates a valuable model to dissect RAS dependency in lung adenocarcinoma. This system allows dissection of EGFR signaling bifurcation, resistance mechanisms to EGFR inhibitors, and the contribution of RAS to tumorigenesis. It also offers a human epithelial context for studying HRAS-related pathologies such as Costello syndrome, and for validating RAS-targeted therapeutic strategies.
Applications include oncogenic RAS signaling studies using Western blotting for p-ERK/p-AKT, RAF1-RBD pull-down for active HRAS, and GTPase assays. Functional readouts such as proliferation, apoptosis, and drug sensitivity assays with MEK inhibitors (trametinib) are readily performed. RT-qPCR can monitor RAS target gene expression. These cells thus facilitate comprehensive analysis of the EGFR?CRAS?CMAPK axis. For further information, contact Ascent Research.
