The KRT5 Knockout CAL-27 Polyclonal Cells are a polyclonal cell population derived from the human oral squamous cell carcinoma line CAL-27, engineered through CRISPR/Cas9-mediated disruption of the KRT5 gene. This product provides a heterogeneous knockout model, enabling loss-of-function studies of keratin 5 (KRT5) without clonal isolation. By targeting KRT5, the cells lack functional keratin 5 protein, which is a critical component of the intermediate filament cytoskeleton in basal epithelial cells. The polyclonal format preserves the genetic diversity inherent to the editing process, allowing researchers to assess population-level phenotypes relevant to epithelial biology and cancer.
CAL-27 is a widely used adherent cell line isolated from a tongue squamous cell carcinoma of a 56-year-old male patient. The line exhibits characteristics of aggressive oral cancer, including rapid proliferation, invasive capacity, and expression of epithelial markers. Its use as a host background places KRT5 disruption in a clinically relevant context for oral squamous cell carcinoma research. The cells retain the molecular features of the parental line, with targeted inactivation of KRT5, making them a powerful tool for dissecting keratin-dependent mechanisms in a malignant epithelial setting.
KRT5 encodes a type II intermediate filament protein that forms obligate heterodimers with keratin 14 (KRT14), a type I keratin, to assemble the cytoskeletal networks that impart mechanical resilience to epithelial cells. The KRT5 gene is transcriptionally regulated by ??Np63 (TP63), a master regulator of epithelial identity, and its expression is modulated by upstream signals from EGF, TGF??, Notch, and WNT pathways. At the protein level, keratin 5 interacts with desmoplakin, plectin, BPAG1, periplakin, envoplakin, and the scaffold protein 14-3-3?? (SFN). These interactions anchor intermediate filaments to desmosomes and hemidesmosomes, thereby stabilizing cell?Ccell and cell?Cmatrix adhesion. Disruption of KRT5 abolishes this network, impairing desmosome integrity, reducing cellular tensile strength, and compromising epithelial barrier function.
In the context of CAL-27 cells, KRT5 knockout substantially alters the mechanical and adhesive properties of the malignant epithelium. Loss of keratin 5?Ckeratin 14 filaments weakens intercellular cohesion and may promote epithelial-to-mesenchymal transition (EMT), a process associated with enhanced tumor invasion and metastasis. The model recapitulates features of diseases such as epidermolysis bullosa simplex, where KRT5 mutations cause skin fragility, and provides a controllable system to study how cytoskeletal defects contribute to oral cancer progression. Researchers can investigate the interplay between mechanical signaling and EMT driven by growth factors like TGF??, as well as the role of keratins in modulating responses to chemotherapeutic agents.
Typical applications include the study of epithelial cell mechanics, keratinocyte biology, drug screening for keratin modulators, and cancer invasion and metastasis research. Representative assays are western blotting for keratin proteins, immunofluorescence to visualize intermediate filament networks, RT-qPCR for KRT5 expression, scratch wound and transwell migration assays to measure motility, mechanical stress assays, co-immunoprecipitation to examine keratin interactions, and histological analysis of epithelial integrity. These polyclonal knockout cells provide a versatile platform for exploring KRT5-related signaling pathways and disease models. For additional information, please contact Ascent Research.
