The IGFBP2 Knockout HCT 116 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout population derived from the human colorectal carcinoma cell line HCT 116, featuring targeted disruption of the IGFBP2 gene. This heterogeneous pool preserves allelic diversity while collectively abolishing functional IGFBP2 protein expression, providing a loss-of-function model suitable for systematic interrogation of IGFBP2-dependent processes. The polyclonal format enables both transient and stable experimental paradigms without the biological averaging inherent to single-cell-derived clones.
HCT 116 is a widely characterized epithelial colorectal carcinoma line harboring KRAS G13D and MLH1 mutations, rendering it aggressively tumorigenic and defective in DNA mismatch repair. These adherent cells proliferate rapidly, maintain robust oncogenic signaling, and readily form xenograft tumors in immunocompromised mice. The parental line expresses endogenous IGFBP2, which contributes to autocrine and paracrine growth factor loops that modulate cancer cell behavior.
IGFBP2 binds insulin-like growth factors I and II (IGF-I and IGF-II) with high affinity, regulating their bioavailability for receptor-mediated signaling. In the canonical pathway, secreted IGFBP2 delivers IGFs to the transmembrane receptor IGF1R, which recruits adaptor protein IRS1 and activates downstream PI3K/AKT and RAS/RAF/MEK/ERK cascades, leading to phosphorylation of AKT, ERK1/2, and STAT3. These kinases transcriptionally regulate targets such as MMP-2 and Bcl-2, influencing matrix degradation and apoptosis. Additionally, IGFBP2 exerts IGF-independent functions by directly interacting with integrin ??5??1, modulating cell adhesion and migration through integrin-signaling pathways. Upstream, its expression is induced by the transcription factor Sp1 and hypoxia (HIF-1??), and is further modulated by growth factors including EGF and TGF-??. Thus, IGFBP2 knockout disrupts both canonical growth factor signaling and integrin-mediated cellular responses.
In colorectal cancer, elevated IGFBP2 correlates with metastatic progression and chemoresistance. In the HCT 116 context, loss of IGFBP2 attenuates AKT- and ERK-driven proliferation, survival, and migration, providing a model to dissect pathway dependencies and the reversal of epithelial-mesenchymal transition. The polyclonal nature mirrors tumor heterogeneity, facilitating investigation of clonal fitness, compensatory signaling, and the emergence of resistance mechanisms under therapeutic pressure.
Applications include quantitative western blotting for phospho-AKT and phospho-ERK1/2, RT-qPCR profiling of downstream transcripts, flow cytometric apoptosis analysis, and proliferation assays (MTT/BrdU). Functional migration and invasion can be assessed via Transwell or wound-healing assays. These cells support co-immunoprecipitation of pathway components, clonogenic survival studies, and xenograft models to evaluate tumor growth and metastasis. This platform is a valuable tool for colorectal cancer biology, drug resistance research, and preclinical target validation. For further technical details, please contact Ascent Research.
