The ADAM17 knockout HT29 polyclonal cells constitute a CRISPR/Cas9-edited polyclonal knockout population targeting the ADAM17 gene (encoding TACE) in the HT29 human colorectal adenocarcinoma cell line. This product comprises a heterogeneous pool of HT29 cells harboring disruptive mutations at the ADAM17 locus, resulting in a loss-of-function model suitable for dissecting ADAM17-dependent signaling pathways. No single-cell clonal selection has been performed, preserving genetic diversity while maintaining uniform ADAM17 deficiency across the population. The cells provide a robust, validated tool for investigating ADAM17-mediated sheddase activity in colorectal cancer biology.
HT29 cells are a widely used model of human colorectal adenocarcinoma, originally derived from a primary tumor of a 44-year-old female. These cells exhibit epithelial morphology and form polarized monolayers with tight junctions, recapitulating key features of the colorectal epithelium. Genomically, HT29 cells harbor mutations in the tumor suppressor genes p53 and APC, while KRAS remains wild-type, making them particularly relevant for studying Wnt/??-catenin and p53 signaling perturbations in colorectal cancer. Their ability to differentiate into enterocyte-like cells under specific conditions further expands their utility in investigating intestinal biology and cancer progression.
ADAM17 (a disintegrin and metalloprotease 17), also known as TNF??-converting enzyme, functions as a primary sheddase that cleaves ectodomains of numerous transmembrane proteins, releasing soluble ligands and receptors. Its activity is regulated by upstream kinases including PKC, ERK, and p38 MAPK, and it is transcriptionally induced by TNF??, IL-1??, EGF, and hypoxia. Key substrates include the membrane-bound proform of TNF??, EGFR ligands such as TGF??, amphiregulin, and HB-EGF, as well as the IL-6 receptor and Notch1. ADAM17 interacts with iRhom1 and iRhom2, which are essential for its maturation and trafficking, and is inhibited by TIMP3 and PDZ-domain proteins. Downstream, shed ligands activate pathways such as EGFR?CERK1/2?CAKT, TNF???CNF-??B, and IL-6R?CSTAT3, orchestrating pleiotropic cellular responses. In addition, ADAM17-mediated release of Notch ligands modulates Notch signaling, influencing cell fate decisions.
In the context of HT29 colorectal cancer cells, ADAM17 plays a pivotal role in autocrine and paracrine signaling loops. Shedding of EGFR ligands leads to constitutive EGFR activation, driving downstream MAPK and NF-??B cascades that promote proliferation, survival, and inflammatory gene expression. This autocrine loop is implicated in chemoresistance and tumor progression. Furthermore, ADAM17-dependent shedding of TNF?? and IL-6R contributes to an inflammatory microenvironment, fostering cancer cell growth. The knockout of ADAM17 in HT29 cells thus provides a powerful system to dissect the contribution of metalloprotease-mediated shedding to colorectal cancer pathobiology, offering insights into mechanisms of growth factor dependency and immune evasion.
These polyclonal knockout cells are suited for a range of research applications, including the study of EGFR ligand shedding, cytokine release, and signaling crosstalk in colorectal cancer. They can be employed in proliferation and migration assays, western blotting to assess ADAM17 expression and phosphorylation of downstream effectors such as ERK1/2 and AKT, and ELISA to quantify soluble TNF?? and TGF?? levels. Flow cytometry enables measurement of surface retention of EGFR ligands following ADAM17 disruption. Additionally, the cells facilitate drug target validation, particularly for ADAM17 inhibitors, and the screening of compounds that modulate metalloprotease activity. For further information or technical support, please contact Ascent Research.
