The HRAS Knockout CAL-27 Polyclonal Cells are a polyclonal cell population generated from the human CAL-27 squamous cell carcinoma line via CRISPR/Cas9-mediated disruption of the HRAS gene. This heterogeneous knockout pool overcomes clonal drift and selection biases, providing a robust model to assess HRAS function within a dynamic cellular context. The polyclonal format captures population-level signaling variations and retains the parental line??s fundamental growth and differentiation characteristics while eliminating wild-type HRAS expression.
CAL-27 cells were originally derived from a tongue squamous cell carcinoma of a 56-year-old male patient and serve as a canonical model for head and neck squamous cell carcinoma (HNSCC). These adherent epithelial cells exhibit tumorigenic properties in vitro and in xenograft assays, with known mutations in TP53 and other cancer-relevant loci. Their oral cavity origin renders them particularly suitable for investigating epithelial?to?mesenchymal transition, invasion, and therapeutic responses relevant to HNSCC progression.
HRAS encodes a small GTPase that operates as a binary switch, cycling between GDP?bound inactive and GTP?bound active conformations. Upstream signals from receptor tyrosine kinases, including EGFR and FGFR, promote GTP loading via SOS1, while NF1 stimulates GTP hydrolysis to return HRAS to the off state. Active HRAS interacts with a spectrum of effectors: it binds RAF1 and BRAF, triggering the MEK1/2?CERK1/2 cascade; activates PI3K, leading to AKT and mTOR signaling; and engages RALGDS to stimulate RalA/B GTPases. This integrated network governs proliferation, survival, and metabolic regulation. Activating mutations in HRAS, which impair intrinsic GTPase activity, result in persistent effector engagement and are oncogenic in multiple tissues, including the head and neck.
In the CAL-27 background, HRAS gene disruption specifically interrogates the contribution of wild?type HRAS to the malignant phenotype. This system allows discrimination between HRAS?dependent and other RAS isoform?driven effects, and facilitates precise assessment of targeted inhibitors, particularly those directed at the MAPK pathway. MEK inhibitor sensitivity, compensatory signaling through PI3K/AKT/mTOR, and RalGDS pathway activation can be systematically evaluated. The model thus provides a genetically tractable platform for dissecting signaling redundancy and adaptive resistance mechanisms in HNSCC cells.
Researchers can employ these polyclonal knockout cells for western blot analysis of phospho?ERK and phospho?AKT, MTT or colony?based proliferation assays, and transwell migration/invasion studies. Drug sensitivity profiling, flow cytometric detection of apoptosis and cell cycle changes, and rescue experiments with HRAS variants further extend the utility. This product is ideally suited for mechanism?of?action studies, targeted therapy development, and head and neck cancer biology. For comprehensive technical specifications and ordering information, please contact Ascent Research.
