The CD34 Knockout CAL-27 Polyclonal Cells constitute a CRISPR/Cas9-edited polyclonal cell population derived from the human CAL-27 tongue squamous cell carcinoma line, engineered for targeted disruption of the CD34 gene. This knockout model abolishes CD34 protein expression within a heterogeneous population, providing a physiologically relevant loss-of-function system for studying CD34-dependent processes in an oral cancer epithelial context. The cells are delivered as a pooled polyclonal population, representing a spectrum of independent editing events and enabling population-level analyses without clonal selection bias. This format is particularly suited for experiments requiring robust representation of phenotypic variability while maintaining stable CD34 ablation across the population.
The parental CAL-27 cell line was originally established from a tongue squamous cell carcinoma excised from a 56-year-old male patient and exhibits adherent epithelial-like morphology typical of oral squamous cell carcinoma. CAL-27 cells harbor TP53 mutations (H193L) and are widely used as a model for head and neck squamous cell carcinoma, displaying characteristic features such as dysregulated proliferation, invasive potential, and chemoresistance. This background offers a clinically relevant platform for investigating the roles of adhesion molecules like CD34 in the behavior of malignant epithelial cells, bridging the gap between hematopoietic stem cell biology and solid tumor pathology.
CD34 is a cell surface sialomucin that serves as a key mediator of cell adhesion and homing, primarily through its interaction with L-selectin (CD62L) and linkage to the actin cytoskeleton via adaptor proteins such as ezrin. CD34 engagement initiates downstream signaling cascades including PI3K/AKT and focal adhesion kinase (FAK) pathways, which regulate survival, migration, and integrin activation. In hematopoietic contexts, CD34 expression is transcriptionally governed by master regulators GATA2 and RUNX1, as well as by NOTCH, TNF-??, and TGF-?? signaling. CD34 also modulates actin polymerization and cytoskeletal reorganization, thereby influencing cell shape and motility. Although classically considered a hematopoietic marker, CD34 is aberrantly expressed in certain solid tumors, including oral squamous cell carcinomas, where it may contribute to malignant progression.
In CAL-27 cells, CD34 knockout is expected to disrupt L-selectin-dependent adhesion and impair downstream PI3K/AKT and integrin-mediated signaling, potentially attenuating the migratory and invasive capacities of these tumor cells. Given the reported association of CD34 expression with stem/progenitor features and therapy resistance in some solid malignancies, this knockout model may exhibit reduced stem-like properties, as assessable by ALDEFLUOR activity and colony formation assays. The polyclonal nature of the knockout population mirrors the genetic heterogeneity observed in clinical tumor specimens, enabling studies that capture a broad spectrum of CD34 loss-of-function effects on cell behavior, from adhesion to drug sensitivity. This model thus provides a valuable tool for dissecting CD34-specific contributions to oral cancer pathogenesis, independent of its hematopoietic role.
Typical research applications include flow cytometric verification of CD34 depletion, quantitative adhesion assays on L-selectin-coated substrates, Transwell migration and invasion screens, and drug sensitivity profiling in the context of CD34 knockout. The cells are also suitable for interrogating the interplay between CD34 and PI3K/AKT or FAK signaling via western blotting and RT-qPCR, as well as for assessing stemness changes using the ALDEFLUOR assay or sphere-formation tests. The CD34 Knockout CAL-27 Polyclonal Cells thus offer a multifaceted platform for exploring oral cancer biology and for screening compounds targeting adhesion-dependent tumor cell functions. For additional information and technical support, please contact Ascent Research.
