The KDM4B Knockout HT29 Polyclonal Cells product consists of a polyclonal population of HT-29 colorectal adenocarcinoma cells edited by CRISPR/Cas9 to disrupt the KDM4B gene. This knockout model enables investigation of KDM4B’s role in histone demethylation and transcriptional regulation without clonal selection, offering a biologically relevant tool for colorectal cancer research. The heterogeneous nature of polyclonal cells reflects a spectrum of editing outcomes, making them suitable for pooled functional genomic screens and studies of gene essentiality.
HT-29 is a human colorectal adenocarcinoma cell line with epithelial morphology, originally isolated from a primary tumor. These cells are extensively characterized for maintaining intestinal epithelial barrier functions, mucin secretion, and nutrient absorption in vitro. Their widespread use in colorectal cancer biology includes studies of tumor progression, metastasis, and drug response, making HT-29 an optimal host for dissecting the oncogenic functions of KDM4B.
KDM4B belongs to the JmjC domain-containing histone demethylase family and specifically removes methyl groups from H3K9me3 and H3K36me3, thereby relieving transcriptional repression. Its expression is induced by HIF-1??, TGF-??, and Wnt/??-catenin signaling, while miR-491-5p negatively regulates it. KDM4B directly activates oncogenic and stemness targets such as CCND1, HOXA cluster genes, SOX2, and NANOG, and also modulates CHD1L, PHLPP2, and MDM2. It forms multiprotein complexes with nuclear receptors (AR, ESR1), tumor suppressors (p53), and chromatin modifiers (HDAC1, SIN3A, CHD4, PARP1) to fine-tune chromatin accessibility and gene expression during cell cycle progression, stem cell maintenance, and DNA damage repair.
In HT-29 colorectal cancer cells, CRISPR/Cas9-mediated KDM4B disruption leads to accumulation of H3K9me3 and H3K36me3 at promoters of critical genes, including CCND1, resulting in transcriptional silencing of proliferative and pluripotency networks. This epigenetic blockade attenuates Wnt/??-catenin and HIF-1?? signaling, curbing cell proliferation, migration, and invasion while promoting apoptosis. The model recapitulates tumor-suppressive effects associated with maintenance of repressive histone marks and may reveal vulnerabilities in DNA repair pathways, offering insights into overcoming chemoresistance in colorectal adenocarcinoma.
Researchers can employ this polyclonal knockout population for various functional studies. ChIP-qPCR and Western blotting measure H3K9me3/H3K36me3 levels, while RT-qPCR or RNA-seq profiles targets like CCND1 and SOX2. Proliferation, migration, and invasion are assessed by MTT, colony formation, and Transwell assays; apoptosis and cell cycle by flow cytometry. Co-IP confirms KDM4B interactions with HDAC1, SIN3A, or PARP1, and luciferase reporters monitor Wnt/??-catenin activity. These tools facilitate epigenetic cancer research, demethylase inhibitor screening, and drug resistance studies.
