Background: Oral squamous cell carcinoma (OSCC) is an oral and maxillofacial malignancy with a high incidence worldwide. Accumulating evidence indicates that circular RNAs (circRNAs) play a vital role in modulating tumor development. However, the mechanism of circRNA action in human OSCC remains largely unknown.
Methods: By using high-throughput transcriptome sequencing technology, we conducted a comprehensive study of circRNAs in human OSCC. The effect of circRNA hsa_circ_0005379 on OSCC tissues and cell lines was monitored by qRT-PCR, Transwell assay, flow cytometry, and western blot analysis. Xenograft mouse models were used to assess tumor growth and animal survival.
Results: We found that circRNA hsa_circ_0005379 expression is significantly lower in OSCC tissue compared to paired non-cancerous matched tissue and is associated with tumor size and differentiation. Overexpression of hsa_circ_0005379 effectively inhibits migration, invasion, and proliferation of OSCC cells in vitro and suppresses OSCC growth in nude mice in vivo. Mechanistic studies revealed that hsa_circ_0005379 may be involved in the regulation of the epidermal growth factor receptor (EGFR) pathway. Furthermore, we found that high expression of hsa_circ_0005379 could significantly enhance the sensitivity of OSCC to the cetuximab drug.
Conclusions: Our findings provide evidence that hsa_circ_0005379 regulates OSCC malignancy and may be a new therapeutic target for OSCC treatment.
Keywords: Cetuximab; Circular RNAs; EGFR pathway; Epithelial–mesenchymal transition; Oral squamous cell carcinoma.