The GRB10 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human HT29 colorectal adenocarcinoma cell line, engineered to disrupt the GRB10 gene. This polyclonal pool features a heterogeneous genetic background, reflecting a realistic population of gene-edited cells for loss-of-function studies. GRB10 encodes an adaptor protein that negatively regulates insulin and insulin-like growth factor 1 (IGF-1) receptor signaling, and its ablation enables investigation of unattenuated signaling in a colorectal cancer context.
HT29 cells, originally isolated from a primary colon tumor, are a well-characterized model for colorectal cancer and intestinal epithelial barrier function. They harbor mutations in key tumor suppressors and oncogenes, such as APC and KRAS, and are widely used in drug screening and oncogenic signaling studies. The polyclonal knockout population on this background preserves the intrinsic molecular heterogeneity of cancer cells, providing a more physiologically relevant system than clonal derivatives.
GRB10 acts as a cytoplasmic adaptor that binds activated insulin receptor (INSR) and IGF1R, blunting signal transduction by competing with insulin receptor substrate 1 (IRS1) for docking sites and facilitating receptor ubiquitination via NEDD4. Upstream, GRB10 expression is regulated by FOXO transcription factors and is induced by insulin or IGF-1. Loss of GRB10 leads to unopposed activation of the PI3K?CAKT1 and MAPK/ERK cascades, causing hyperphosphorylation of AKT1, ERK1/2, and mTORC1, which drive proliferation, survival, and metabolic processes.
In colorectal cancer, aberrant insulin and IGF-1 signaling promotes tumorigenesis and therapy resistance. GRB10 knockout in HT29 cells removes a critical negative feedback mechanism, resulting in sustained PI3K?CAKT and MAPK/ERK pathway activity that may enhance cell growth and metabolic reprogramming. This model is valuable for studying the interplay between systemic metabolic signals and colorectal cancer, and the polyclonal nature allows analysis of response heterogeneity and identification of GRB10-dependent subpopulations.
Researchers can employ this model to dissect insulin/IGF-1 signaling through phospho-protein analysis (e.g., phospho-AKT and phospho-ERK immunoblotting), transcriptional profiling via RT-qPCR or RNA-seq, and functional assays such as cell proliferation (MTT/BrdU) and apoptosis under insulin stimulation. It is also suited for drug sensitivity screening to identify inhibitors of hyperactivated PI3K?CAKT or MAPK pathways and for functional genomics studies exploring synthetic lethality. For further information, please contact Ascent Research.
