The prevalence and invasiveness of cutaneous squamous cell carcinoma (cSCC), one of the most prevalent non-melanoma skin malignancies, are increasing annually. Effective biomarkers and targeted therapeutics for locally advanced, metastatic cSCC (i.e., tumors that are difficult to manage surgically due to extensive local invasion or distant spread) as well as for recurrent cSCC are still lacking, despite surgical resection being the primary therapy approach. Circular RNA (circRNA) has drawn a lot of interest lately in relation to cancer and development. There is evidence that circRNA can regulate biological processes like cell migration, invasion, and proliferation by acting as microRNA (miRNA) sponges. Furthermore, because of its tissue-specific expression, high stability, and wide range of regulatory roles, circRNA has demonstrated considerable relevance as a diagnostic marker and possible therapeutic target. This study provides a systematic review of the literature regarding the expression profiles of circRNAs in cSCC, the associated circRNA-miRNA-mRNA regulatory networks and molecular mechanisms, the involved signaling pathways, and their potential as therapeutic targets and diagnostic biomarkers. These findings may offer new approaches to the diagnosis, monitoring, and prognosis of cSCC.
Keywords: biomarker; circRNA; cutaneous squamous cell carcinoma; molecular mechanism; molecular sponge.
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