The CBX8 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colon adenocarcinoma cell line, engineered to disrupt the CBX8 gene. This product provides a heterogeneous knockout model for studying loss-of-function effects of the chromobox protein CBX8, a core component of the Polycomb repressive complex 1 (PRC1). The polyclonal nature ensures representation of diverse editing events, offering a robust tool for functional genomics and cancer research without requiring single-cell clonal isolation.
The HT29 cell line, isolated from a primary colorectal adenocarcinoma of a 44-year-old Caucasian female, is a widely used epithelial model of intestinal differentiation and colon tumorigenesis. HT29 cells maintain the capacity to undergo enterocytic differentiation under defined conditions, making them particularly suitable for investigating the interplay between epigenetic regulation and cellular differentiation programs in colorectal cancer.
CBX8 functions as a reader of trimethylated lysine 27 on histone H3 (H3K27me3), a hallmark of facultative heterochromatin, via its chromodomain. As part of PRC1, it collaborates with RING1B, BMI1, and PHC proteins to mediate chromatin compaction and gene silencing. CBX8 activity is regulated by upstream signals including SHH-GLI, Wnt/??-catenin, MYC, and E2F, and its overexpression in colorectal cancer represses key tumor suppressor loci such as the INK4a/ARF locus (CDKN2A), encoding p16INK4a and p14ARF, while also downregulating E-cadherin (CDH1). Additionally, CBX8 interacts with ??-catenin and epigenetic modifiers like DNA methyltransferases and histone deacetylases, reinforcing transcriptional silencing of pro-apoptotic and pro-differentiation genes.
In the HT29 colorectal adenocarcinoma context, CBX8 is frequently overexpressed and contributes to malignant phenotypes by maintaining a dedifferentiated, proliferative state. Disruption of CBX8 in this background provides a powerful model to dissect its role in tumor maintenance, epithelial-mesenchymal transition, and stem cell-like properties. The polyclonal knockout population enables the study of CBX8-dependent gene expression changes and epigenetic reprogramming at the bulk level, facilitating experiments that require sufficient cell numbers for biochemical assays such as ChIP-qPCR and co-immunoprecipitation.
These polyclonal knockout cells are suitable for a breadth of applications in colorectal cancer research, including chromatin immunoprecipitation coupled with quantitative PCR (ChIP-qPCR) to assess H3K27me3 dynamics, RNA-seq to profile global transcriptomic alterations, and western blotting or RT-qPCR to validate CBX8-dependent target expression (e.g., p16INK4a, p14ARF, CDH1). Functional studies such as colony formation, migration/invasion, and apoptosis assays (Annexin V) can characterize phenotypic consequences of CBX8 loss. Further, these cells serve as a platform for drug target discovery and screening of agents that modulate Polycomb function. For inquiries regarding use and availability, please contact Ascent Research.
