The ACE2 Knockout CAL-27 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the CAL-27 human tongue squamous cell carcinoma line. The ACE2 gene is disrupted by targeted Cas9-mediated cleavage, resulting in a heterogeneous mixture of cells with loss-of-function alleles. This ablation of ACE2 protein expression provides a controlled model to decipher ACE2-dependent pathways without residual wild-type activity, facilitating functional genomics, disease modeling, and drug target validation in an oral cancer context.
CAL-27 is an established cell line isolated from a human tongue squamous cell carcinoma, a prevalent oral malignancy with high invasive capacity. It retains the defining characteristics of the original tumor, including genetic alterations and phenotypic traits such as rapid proliferation and motility, making it a valuable host for oral cancer research. The epithelial origin of CAL-27 allows for the investigation of gene function in a clinically relevant setting for head and neck cancers.
ACE2 encodes a carboxypeptidase that converts angiotensin II into angiotensin-(1-7), a heptapeptide that acts via the Mas receptor to induce vasodilation, anti-inflammatory responses, and nitric oxide production. This reaction counteracts the angiotensin II/AT1R axis, which promotes vasoconstriction and pro-inflammatory signaling. ACE2 also serves as the cellular receptor for SARS-CoV-2 by binding the viral spike protein, and it heterodimerizes with the amino acid transporter SLC6A19 (B0AT1) to facilitate neutral amino acid uptake. The enzyme is subject to cleavage by ADAM17 and is transcriptionally regulated by factors including FOXO1, SIRT1, IFN-??, and TNF-??. Disruption of ACE2 in these cells abolishes angiotensin-(1-7) generation, enhancing angiotensin II/AT1R activity, eliminates SARS-CoV-2 entry, and impairs B0AT1-mediated transport.
In the oral cancer context, loss of ACE2 shifts the equilibrium toward angiotensin II-driven tumorigenic processes such as proliferation, migration, and invasion, while removing the protective ACE2/Ang-(1-7)/Mas signaling. This makes the knockout cells a powerful system to dissect the role of the renin-angiotensin system in oral squamous cell carcinoma progression. Moreover, the absence of SARS-CoV-2 receptor renders the cells refractory to viral entry, providing a stringent negative control for infection studies and a platform to evaluate ACE2-dependent antiviral strategies.
Typical applications encompass functional assays for cell proliferation (e.g., BrdU, colony formation), migration (wound healing), and invasion (transwell), as well as molecular analyses via Western blotting and RT-qPCR. The cells are ideal for angiotensin conversion assays to quantify ACE2 activity, SARS-CoV-2 pseudovirus entry tests, and immunofluorescence localization studies. RNA-seq and drug screening efforts benefit from this comprehensive loss-of-function resource. For technical inquiries, please contact Ascent Research.
