MicroRNAs and Lymph Node Metastasis in Papillary Thyroid Cancers

Abstract

Lymph node metastasis (LNM) in papillary thyroid cancer (PTC) has been shown to be associated with increased risk of locoregional recurrence, poor prognosis and decreased survival, especially in older patients. Hence, there is a need for a reliable biomarker for the prediction of LNM in this cancer. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene translation or degradation and play key roles in numerous cellular functions including cell-cycle regulation, differentiation, apoptosis, invasion and migration. Various studies have demonstrated deregulation of miRNA levels in many diseases including cancers. While a large number of miRNAs have been identified from PTCs using various means, association of miRNAs with LNM in such cases is still controversial. Furthermore, studies linking most of the identified miRNAs to the mechanism of LNM have not been well documented. The aim of this review is to update readers on the current knowledge of miRNAs in relation to LNM in PTC.

Overexpression of LncRNA HOTAIR is Associated with Poor Prognosis in Thyroid Carcinoma: A Study Based on TCGA and GEO Data

“…However, the occurrence and progression of TC were generally attributed to long-term interactions between environmental and genetic factors. Accumulating studies have re- ported that molecular mechanisms act an important role in human thyroid carcinogenesis and a large number of ncRNAs participate in the process [3,5,29,30]. Hence, it is of important significance to excavate abnormally expressed lncRNAs and their related signaling pathways, which will provide adequate theoretical basis to interpret the underlying mechanisms and to search effective therapeutic targets for TC.…”

“…Thyroid carcinoma (TC) is the most common malignancy of endocrine organs worldwide, with steadily increasing morbidity during the last 3 decades [1,2]. To date, numerous studies have suggested that complex biological processes involving the interaction of multiple genes might participate in the development of TC [3][4][5]. In addition to protein-coding genes, 6 types of long noncoding RNAs (lncRNAs) have recently been reported to be involved in human thyroid carcinogenesis, including MEG3 [6], PTCSC3 [7], BANCR [8], PVT1 [9], NONHSAT037832 [10], and LOC100507661 [11].…”

MicroRNA‑766 inhibits papillary thyroid cancer progression by directly targeting insulin receptor substrate 2 and regulating the PI3K/Akt pathway

“…Previous studies have reported that miRNAs are aberrantly expressed in almost all types of human cancer, including PTC (12), colorectal cancer (13), lung cancer (14), glioblastoma (15) MicroRNA-766 inhibits papillary thyroid cancer progression by directly targeting insulin receptor substrate 2 and regulating the PI3K/Akt pathway and bladder cancer (16). Increasing evidence has revealed that various miRNAs are differentially expressed in PTC, and their dysregulation has been implicated in the regulation of PTC occurrence and development (17)(18)(19). Furthermore, miRNAs may have tumor suppressive or oncogenic roles in the progression of PTC and are able to regulate various cancer-associated biological processes, including cell proliferation, cell cycle progression, apoptosis, invasion, metastasis and epithelial-mesenchymal transition (20)(21)(22).…”

MKL1 overexpression predicts poor prognosis in patients with papillary thyroid cancer and promotes nodal metastasis

“…Recently, relying on molecular and genetic analysis, BRAF-only mutations have been found as the most frequent molecular alterations in LNM, whereas TERTp-only mutations are the most frequent alterations in distant metastasis (Melo et al, 2017). In addition, several miRNAs, such as miRNA-146b and miR-221/222, have also been shown to be potential biomarkers in predicting LNM (Mutalib et al, 2016). To date, studies focusing on the involvement of protein biomarkers in PTC with LNM are quite limited.…”