Validation of MicroRNA-188-5p Inhibition Power on Tumor Cell Proliferation in Papillary Thyroid Carcinoma

Potential roles of FGF5 as a candidate therapeutic target in prostate cancer

Fibroblast growth factor (FGF) is a secreted ligand that is widely expressed in embryonic tissues but its expression decreases with age. In the developing prostate, FGF5 has been proposed to interact with the Hedgehog (Hh) signaling pathway to guide mitogenic processes. In the adult prostate, the FGF/FGFR signaling axis has been implicated in prostate carcinogenesis, but focused studies on FGF5 functions in the prostate are limited. Functional studies completed in other cancer models point towards FGF5 overexpression as an oncogenic driver associated with stemness, metastatic potential, proliferative capacity, and increased tumor grade. In this review, we explore the significance of FGF5 as a therapeutic target in prostate cancer (PCa) and other malignancies; and we introduce a potential route of investigation to link FGF5 to benign prostatic hyperplasia (BPH). PCa and BPH are two primary contributors to the disease burden of the aging male population and have severe implications on quality of life, psychological wellbeing, and survival. The development of new FGF5 inhibitors could potentially alleviate the health burden of PCa and BPH in the aging male population.

Curcumin inhibits the viability, migration and invasion of papillary thyroid cancer cells by regulating the miR-301a-3p/STAT3 axis

Thyroid cancer is one of the most common malignant tumors, and the mortality rate associated with thyroid cancer has been increasing annually. Curcumin has been reported to exert an antitumor effect on papillary thyroid cancer (PTC), and the identification of additional mechanisms underlying the anticancer effect of curcumin on PTC requires further investigation. The present study aimed to explore the effects of curcumin on the viability, migration and invasion of PTC cells. TPC-1 cells were incubated with different concentrations of curcumin, and then, cell viability, migration and invasion, and wound healing were examined by CCK-8, Transwell and wound healing assays, respectively. Subsequently, microRNA (miR)-301a-3p mimics, miR-301a-3p inhibitors and signal transducer and activator of transcription (STAT)3 overexpression vector were transfected into TPC-1 cells, and cell viability, migration, and invasion were reassessed in these transfected cells. Matrix metallopeptidase (MMP)-2, MMP-9, epithelial-mesenchymal transition (EMT)-related markers, and Janus kinase (JAK)/STAT signaling pathway components were assessed by western blot analysis. Curcumin significantly inhibited cell viability, migration and invasion and downregulated MMP-2, MMP-9 and EMT marker expression. Additionally, curcumin decreased STAT3 expression by upregulating miR-301a-3p expression, and the inhibition of miR-301a-3p and the overexpression of STAT3 reversed the effects of curcumin on cell viability, migration and invasion, and MMP-2, MMP-9 and EMT marker expression in TPC-1 cells. Furthermore, curcumin suppressed the JAK/STAT signaling pathway through the miR-301a-3p/STAT3 axis. The data of the present study indicated that curcumin could inhibit the viability, migration and invasion of TPC-1 cells by regulating the miR-301a-3p/STAT3 axis. These findings may provide a possible strategy for the clinical treatment of PTC.

Circular RNA circ_0062389 modulates papillary thyroid carcinoma progression via the miR-1179/high mobility group box 1 axis

Circular RNAs (circRNAs) feature prominently in regulating the progression of tumors, including papillary thyroid carcinoma (PTC). This work is designated to delve into the role of circ_0062389 in PTC. Generally, quantitative real-time polymerase chain reaction (qRT-PCR) was employed to detect circ_0062389, miR-1179 and high mobility group box 1 (HMGB1) mRNA expression levels. RNase R assay was used to verify the circular characteristics of circ_0062389. After circ_0062389 was knocked down in PTC cells, CCK-8 assay was adopted to determine cell viability. Wound healing assay was leveraged to probe cell migration. Besides, Western blot assay was executed to examine the expression levels of HMGB1 and epithelial-mesenchymal transformation (EMT)-related markers (E-cadherin and N-cadherin). Dual-luciferase reporter assay was performed to authenticate the targeting relationships between miR-1179 and circ_0062389, as well as miR-1179 and HMGB1. Here, this work proved that circ_0062389 was greatly up-regulated in PTC tissues and cell lines. The high expression of circ_0062389 was related to large tumor size and positive lymphatic metastasis. Knocking down circ_0062389 could inhibit the proliferation, migration and EMT process of PTC cells. Besides, miR-1179 was a downstream molecule of circ_0062389. Furthermore, miR-1179 inhibitors could partially reverse the above effect of knocking down circ_0062389 on PTC cells. It was also confirmed that HMGB1 was a direct target of miR-1179 and mediated the effects of circ_0062389 and miR-1179 in PTC. Altogether, circ_0062389 can adsorb miR-1179, and regulate HMGB1 expression, thus playing a role in PTC.

Epigenetic signature associated with thyroid cancer progression and metastasis

Thyroid cancer is not among the top cancers in terms of diagnosis or mortality but it still ranks fifth among the cancers diagnosed in women. Infact, women are more likely to be diagnosed with thyroid cancer than the males. The burden of thyroid cancer has dramatically increased in last two decades in China and, in the United States, it is the most diagnosed cancer in young adults under the age of twenty-nine. All these factors make it worthwhile to fully understand the pathogenesis of thyroid cancer. Towards this end, microRNAs (miRNAs) have constantly emerged as the non-coding RNAs of interest in various thyroid cancer subtypes on which there have been numerous investigations over the last decade and half. This comprehensive review takes a look at the current knowledge on the topic with cataloging of miRNAs known so far, particularly related to their utility as epigenetic signatures of thyroid cancer progression and metastasis. Such information could be of immense use for the eventual development of miRNAs as therapeutic targets or even therapeutic agents for thyroid cancer therapy.

miR‑122‑5p suppresses the oncogenesis of PTC by inhibiting DUSP4 expression

MicroRNAs (miRNAs or miRs) play an important role in regulating the occurrence and development of papillary thyroid carcinoma (PTC). miR‑122‑5p is widely considered a tumour inhibitor, which has not been fully explored in PTC. Bioinformatics analysis identified dual specificity phosphatase 4 (DUSP4), a tumour promoter gene for PTC, as a downstream target of miR‑122‑5p. The aim of the present study was to investigate the role and molecular mechanism of miR‑122‑5p in PTC oncogenesis. In this study, the expression pattern of miR‑122‑5p in PTC cancer tissues and PTC cell lines was investigated via reverse transcription‑quantitative PCR. Furthermore, the roles of miR‑122‑5p in PTC were explored using gain‑of‑function and loss‑of‑function assays. The results revealed that the expression of miR‑122‑5p was significantly lower in PTC cancer tissues, especially in cancer tissues with significant invasion or metastasis. Overexpression of miR‑122‑5p caused by miR‑122‑5p mimics inhibited the proliferation, invasion, and migration of the PTC cell line K1, while knockdown of miR‑122‑5p by miR‑122‑5p inhibitors exhibited the opposite effect. Furthermore, in vivo assays revealed that miR‑122‑5p overexpression inhibited tumour growth. In addition, miR‑122‑5p was negatively correlated with DUSP4 expression in PTC cancer tissues. miR‑122‑5p overexpression inhibited DUSP4 expression in K1 cells, while miR‑122‑5p downregulation produced the inverse effect. Specifically, a luciferase reporter assay confirmed the binding sites of miR‑122‑5p on the 3'‑UTR of DUSP4, demonstrating the targeting effect of miR‑122‑5p on DUSP4. miR‑122‑5p inhibited the oncogenesis of PTC by targeting DUSP4, revealing the potential application value of miR‑122‑5p in the diagnosis and treatment of PTC.

MicroRNA in Papillary Thyroid Carcinoma: A Systematic Review from 2018 to June 2020

Simple Summary

The most common form of endocrine cancer - papillary thyroid carcinoma, has an increasing incidence. Although this disease usually has an indolent behavior, there are cases when it can evolve more aggressively. It has been known for some time that it is possible to use microRNAs for the diagnosis, prognosis and even treatment monitoring of papillary thyroid cancer. The purpose of this study is to summarize the latest information provided by publications regarding the involvement of microRNAs in papillary thyroid cancer, underling the new clinical perspectives offered by these publications.

Abstract

The involvement of micro-ribonucleic acid (microRNAs) in metabolic pathways such as regulation, signal transduction, cell maintenance, and differentiation make them possible biomarkers and therapeutic targets. The purpose of this review is to summarize the information published in the last two and a half years about the involvement of microRNAs in papillary thyroid carcinoma (PTC). Another goal is to understand the perspective offered by the new findings. Main microRNA features such as origin, regulation, targeted genes, and metabolic pathways will be presented in this paper. We interrogated the PubMed database using several keywords: “microRNA” + “thyroid” + “papillary” + “carcinoma”. After applying search filters and inclusion criteria, a selection of 137 articles published between January 2018–June 2020 was made. Data regarding microRNA, metabolic pathways, gene/protein, and study utility were selected and included in the table and later discussed regarding the matter at hand. We found that most microRNAs regularly expressed in the normal thyroid gland are downregulated in PTC, indicating an important tumor-suppressor action by those microRNAs. Moreover, we showed that one gene can be targeted by several microRNAs and have nominally described these interactions. We have revealed which microRNAs can target several genes at once.