The EGFR Knockout HCT 116 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population targeting the EGFR gene in HCT 116 human colorectal carcinoma cells (Homo sapiens). This gene-edited model enables investigation of EGFR function in a well-characterized epithelial cancer background. The polyclonal format preserves cellular heterogeneity, providing a robust platform for assessing EGFR-dependent phenotypes without clonal selection artifacts. CRISPR/Cas9-mediated gene disruption allows researchers to interrogate the roles of EGFR in signal transduction networks that govern proliferation, survival, and migration.
HCT 116 is a colorectal carcinoma epithelial cell line with a microsatellite instability-high (MSI-H) phenotype, a heterozygous KRAS G13D mutation, and wild-type TP53. These features make it a representative model for a subset of human colorectal cancers. The cells exhibit rapid growth and well-defined signaling, facilitating dissection of oncogenic pathways. Introducing EGFR knockout into this MLH1-deficient, KRAS-mutant background allows examination of EGFR cooperation with mutant KRAS and analysis of signaling redundancy in a clinically relevant tumor context.
EGFR encodes a receptor tyrosine kinase that binds EGF-family ligands (e.g., EGF, TGF-??, amphiregulin) leading to receptor dimerization and autophosphorylation. Phosphotyrosine residues recruit adaptors GRB2, SHC1, and GAB1, which activate the RAS?CRAF?CMEK?CERK cascade, driving transcription via ELK1 and FOS. EGFR also stimulates PI3K?CAKT?CmTOR signaling to enhance survival and protein synthesis, and PLC?èCPKC and JAK/STAT pathways. Interacting proteins CBL and SRC regulate receptor trafficking and signaling amplitude. In HCT 116 cells, CRISPR/Cas9-mediated EGFR disruption impairs ligand-induced activation of these networks, reducing proliferative and migratory responses.
Loss of EGFR in HCT 116 cells permits dissection of EGFR-dependent versus KRAS-driven signaling in an MSI-H colorectal carcinoma environment. Given the presence of oncogenic KRAS G13D, this knockout model is valuable for studying compensatory pathway activation, drug resistance mechanisms, and combination therapy strategies. The polyclonal population provides a more representative picture of therapeutic response and adaptive rewiring, avoiding clonal bias. Researchers can investigate how EGFR loss sensitizes cells to targeted agents or how KRAS mutation sustains signaling independently.
This cell model supports diverse functional and pharmacological assays. Western blotting can detect loss of EGFR and reduced phosphorylation of downstream effectors (ERK, AKT). RT-qPCR quantifies immediate early gene induction (FOS, JUN) after stimulation. Flow cytometry enables cell cycle and apoptosis analyses. Proliferation assays (MTS/MTT) and colony formation assess growth, while migration/invasion assays evaluate metastatic potential. Drug sensitivity profiling with EGFR inhibitors (cetuximab, gefitinib) can be performed to dissect resistance. This versatile tool empowers cancer signaling research and drug development. For more information, contact Ascent Research.
