MicroRNA Role in Thyroid Cancer Development

Abstract

MicroRNAs (miRNAs) are endogenous noncoding RNAs that negatively regulate gene expression by binding the 3′ noncoding region of the messenger RNA targets inducing their cleavage or blocking the protein translation. They play important roles in multiple biological and metabolic processes, including developmental timing, signal transduction, and cell maintenance and differentiation. Their deregulation can predispose to diseases and cancer. miRNA expression has been demonstrated to be deregulated in many types of human tumors, including thyroid cancers, and could be responsible for tumor initiation and progression. In this paper we reviewed the available data on miRNA deregulation in different thyroid tumors and describe the putative role of miRNA in thyroid cancer development.

Heterochromatin protein 1 expression is reduced in human thyroid malignancy

“…17,19 We observed a strong negative correlation of miR-205 and HP1b expression (Pearson r ¼ À 0.52) in previously published array data from papillary carcinomas (Figure 3a). 21 These data show that miR-205 and HP1b were significantly up and downregulated (Po0.05), respectively in these tumors.…”

“…16 It has been proposed that of the miRNAs that are dysregulated only those which are highly overexpressed or strongly downregulated are involved in thyroid tumorigenesis. 17 Thyroid cancers exhibit aberrant miRNA expression that leads to the altered expression of oncogenes as well as tumor suppressor genes. 17,18 Interestingly, several miRNAs that are differentially upregulated in thyroid lesions are also predicted to target the HP1 family.…”

“…17 Thyroid cancers exhibit aberrant miRNA expression that leads to the altered expression of oncogenes as well as tumor suppressor genes. 17,18 Interestingly, several miRNAs that are differentially upregulated in thyroid lesions are also predicted to target the HP1 family. 19 The need for improved accuracy in the diagnosis of thyroid lesions has led us to explore the expression of HP1a and HP1b across benign and malignant thyroid tumors, respectively.…”

MicroRNA-134 targets KRAS to suppress breast cancer cell proliferation, migration and invasion

“…Dysregulated miRNA expression has been observed in various types of human malignancies, including breast cancers (17). These previous studies indicated that specific dysregulated miRNAs may serve as useful biomarkers for breast cancer tumorigenesis, progression and clinical prognosis, as well as potential targets for breast cancer therapy (16,17).…”

“…Previous studies have suggested that specific miRNAs may be downregulated or upregulated in certain types of tumors (13)(14)(15). Downregulated miRNAs may normally function as tumor suppressor genes, whereas upregulated miRNAs may normally function as oncogenes (16). Dysregulated miRNA expression has been observed in various types of human malignancies, including breast cancers (17).…”