Serum miRNAs as Biomarkers for the Diagnosis and Prognosis of Thyroid Cancer: A Comprehensive Review of the Literature
Background/Objectives: Thyroid cancer is the most common endocrine malignancy and accounts for 1% of cancers. In recent years, there has been much interest in the feasibility of using miRNAs or miRNA panels as biomarkers for the diagnosis of thyroid cancer. miRNAs are noncoding RNAs with 21–23 nucleotides that are highly conserved during evolution. They have been proposed as regulators of gene expression, apoptosis, cancer, and cell growth and differentiation. Methods: The Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO), and Web of Science were searched. Results: The serum level of miRNAs (miRNA-375, 34a, 145b, 221, 222, 155, Let-7, 181b) can be used as molecular markers for the diagnosis and prognosis of thyroid cancer in the serum samples of patients with thyroid glands. Conclusions: Given that most common methods for the screening of thyroid cancer cannot detect the disease in its early stages, identifying miRNAs that are released in the bloodstream during the gradual progression of the disease is considered a key method in the early diagnosis of thyroid cancers.