EZH2 knockout in oral cavity basal epithelia causes more invasive squamous cell carcinomas.

TitleEZH2 knockout in oral cavity basal epithelia causes more invasive squamous cell carcinomas.
Publication TypeJournal Article
Year of Publication2021
AuthorsBaquero J, Tang X-H, Scognamiglio T, Gudas LJ
Date Published2021 12 31
KeywordsAnimals, Biomarkers, Tumor, Cell Line, Tumor, Disease Models, Animal, Disease Susceptibility, DNA Methylation, Enhancer of Zeste Homolog 2 Protein, Epigenesis, Genetic, Gene Expression Regulation, Neoplastic, Gene Knockdown Techniques, Genetic Predisposition to Disease, Histones, Humans, Hyaluronan Receptors, Immunohistochemistry, Mice, Mice, Transgenic, Mouth Mucosa, Neoplasm Invasiveness, Phosphorylation, Squamous Cell Carcinoma of Head and Neck, STAT3 Transcription Factor, Tamoxifen, Xenograft Model Antitumor Assays

Oral squamous cell carcinoma (oral SCC) is an aggressive disease and despite intensive treatments, 5-year survival rates for patients have remained low in the last 20 years. Enhancer of zeste homolog 2 (EZH2), part of polycomb repressive complex 2 (PRC2), is highly expressed in human oral SCC samples and cell lines and has been associated with greater epithelia-to-mesenchymal transition (EMT), invasion and metastasis. Here, we developed a tamoxifen-regulated, transgenic mouse line (KcEZH2) in which EZH2 is selectively knocked out (KO) in some tongue epithelial basal stem cells (SCs) in adult mice. EZH2 KO SCs do not show the H3K27me3 mark, as assessed by double-label immunofluorescence. We used this mouse line to assess EZH2 actions during oral tumorigenesis with our immunocompetent 4-nitroquinoline 1-oxide model of oral SCC. We report that higher percentages of mice with invasive SCCs and high-grade neoplastic lesions are observed in mice containing EZH2 KO SCs (KcEZH2-2TΔ and KcEZH2-5TΔ mice). Moreover, EZH2 expression does not correlate with the expression of markers of invasive SCCs. Finally, EZH2 KO cells that are E-cadherin+ are present at invasion fronts infiltrating underlying muscle tissue. Our findings indicate that the knockout of EZH2 in basal SCs of tongue epithelia results in more aggressive carcinomas, and this should be considered when targeting EZH2 as a therapeutic strategy.

Alternate JournalCarcinogenesis
PubMed ID34614148
PubMed Central IDPMC8727743
Grant ListR01 CA205258 / CA / NCI NIH HHS / United States
T32 CA062948 / CA / NCI NIH HHS / United States
/ / Weill Cornell Medical College /
T32 CA062948 / NH / NIH HHS / United States