ID3 Knockout HCT 116 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population designed for loss-of-function analysis of the inhibitor of DNA binding 3 (ID3) gene. This product consists of a genetically diverse pool of HCT 116 cells harboring targeted disruption of endogenous ID3, achieved through CRISPR/Cas9-mediated gene editing. The polyclonal nature circumvents clonal artifacts and preserves biological variability, making it ideal for functional genomics studies, drug screening, and pathway interrogation where heterogeneous knockout responses are desired.
The HCT 116 cell line is a well-established model of human colorectal carcinoma, exhibiting epithelial morphology and oncogenic mutations in KRAS (G13D) and PIK3CA (H1047R). Additionally, these cells are mismatch repair-deficient due to MLH1 loss, recapitulating features of microsatellite instability-high colorectal cancer. This genetic context makes HCT 116 particularly relevant for investigating tumorigenesis, metastasis, and therapeutic resistance mechanisms.
ID3 functions as a dominant-negative helix-loop-helix (HLH) protein that lacks a basic DNA-binding domain, thereby dimerizing with and inhibiting ubiquitous E-proteins such as E2A (TCF3), HEB (TCF12), and E2-2 (TCF4). ID3 expression is transcriptionally activated by TGF-?? and BMP ligands (BMP2, BMP4) through SMAD2/3?CSMAD4 complexes, and by Wnt3a via ??-catenin/TCF/LEF, while Notch signaling also contributes. ID3 interacts with MyoD and p53, and its inhibition releases E-proteins to transcriptionally regulate target genes including the cyclin-dependent kinase inhibitor p21 (CDKN1A), cyclin D1 (CCND1), and MYC, ultimately controlling cell cycle progression, differentiation, and apoptosis.
In the HCT 116 colorectal cancer background, knockout of ID3 is expected to relieve E-protein suppression, leading to upregulation of p21 and possible cell cycle arrest or differentiation, while decreasing cyclin D1-dependent proliferation. This model allows dissection of ID3’s role in stemness, epithelial-mesenchymal transition, and resistance to chemotherapeutics within the context of activated KRAS and PIK3CA signaling. Consequently, these cells serve as a powerful tool to explore ID3-dependent vulnerabilities in mismatch repair-deficient colorectal cancer.
These polyclonal knockout cells are suitable for diverse applications including colorectal cancer progression studies, cancer stem cell research, drug resistance and immune evasion analyses, and differentiation therapy exploration. Researchers can validate knockout efficiency and downstream effects via western blotting and RT-qPCR, assess proliferation with MTS/CCK8 and colony formation assays, profile cell cycle and apoptosis by flow cytometry, and analyze tumor growth in xenograft models. Global transcriptional changes can be examined by RNA-seq, and E-protein target occupancy by ChIP-seq. For further information or to request custom products, please contact Ascent Research.
