microRNA-539 functions as a tumor suppressor in papillary thyroid carcinoma via the transforming growth factor β1/Smads signaling pathway by targeting secretory leukocyte protease inhibitor

Prognostic Roles of ZNF703 and SMAD4 Expression in Patients with Papillary Thyroid Cancer and Association with Nodal Metastasis

It is important to detect novel predictive biomarkers of cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) to help the surgeons in making early decision of performing central lymph node dissection and aggressive management strategies in selected high-risk patients, thus improving their prognosis. Zinc finger protein 703 (ZNF703) is a member of the neutrophil extracellular trap (NET) transcription factors family which has roles in proliferation and invasion of cancer cells. SMAD4 is a protein that has a role in cellular processes including cell proliferation, invasion, and metastasis through many genes' transcription. In this study, we aimed to assess the expression of ZNF703 and SMAD4 in PTC and evaluated the correlation between its expression, clinicopathological features of PTC cases, and prognostic parameters of patients to evaluate their roles in PTC progression. This is a retrospective study which included 40 cases with PTC. For immunohistochemistry, tissues stained their paraffin blocks with ZNF703 and SMAD4. We followed patients to detect disease progression and recurrence. Positive ZNF703 expression and negative SMAD4 expression were associated with higher incidence of CLNM, advanced stage and large tumor size, higher incidence of disease progression, recurrence, unfavorable PFS, and unfavorable OS rates. The higher ZNF703 expression and the lower SMAD4 expression were significantly increased in PTC patients with cervical LNM compared with those without. ZNF703 over expression and downregulation SMAD4 expression was significantly increased in PTC patients. Elevated expression of ZNF703 in tumor tissue with CLNM can be considered a predictive factor for the development of metastasis.

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.

The Inhibition of Inflammatory Signaling Pathway by Secretory Leukocyte Protease Inhibitor can Improve Spinal Cord Injury

Spinal cord injury leads to loss of sensory motor functions below the damaged area, and can significantly affects physical and mental health. An effective spinal cord injury treatment is currently unavailable, in part, because of the intricacy of the brain, as well as the complex pathophysiological mechanism of the injury. Inflammation is an important biological process in multitudinous diseases, with no exception for spinal cord injury. Nuclear factor kappa beta (NF-κB) signaling pathway is a key inflammatory element, as it is involved in cell survival, apoptosis, proliferation, differentiation, and immune response. Activation of the NF-κB signaling pathway leads to the release of a large number of inflammatory factors that can affect tissue repair. Hence, the inhibition of inflammatory responses could improve the repair of injured spinal cord tissues. Secretory leukocyte protease inhibitor (SLPI) has anti-inflammatory and anti-bacterial properties, and promotes wound healing. SLPI can bind to the promoter region of tumor necrosis factor-αand interleukin-8 (IL-8) to inhibit the NF-κB signaling pathway. Additionally, SLPI can reduce secondary damages after spinal cord injury, and prevent further complications. In this report, we analyze the pathophysiological mechanism of spinal cord injury, the role of NF-κB signaling pathway following spinal cord injury, and how SLPI regulates the NF-κB signaling pathway to curtail inflammatory reaction.

MicroRNA-497 elevation or LRG1 knockdown promotes osteoblast proliferation and collagen synthesis in osteoporosis via TGF-β1/Smads signalling pathway

MicroRNAs (miRNAs) have been corroborated to engage in the process of cellular activities in osteoporosis. However, few researches have been conducted to expose the integrated role of miR‐497, leucine‐rich alpha‐2‐glycoprotein‐1 (LRG1) and transforming growth factor beta 1 (TGF‐β1)/Smads signalling pathway in osteoporosis. Thereafter, the study is set out to delve into miR‐497/LRG1/TGF‐β1/Smads signalling pathway axis in osteoporosis. Osteoporosis bone tissues and normal bone tissues were collected. Rat osteoporosis models were constructed via ovariectomy. Model rats were injected with restored miR‐497 or depleted LRG1 to explore their roles in osteoporosis. Rat osteoblasts were extracted from osteoporosis rats and transfected with restored miR‐497 or depleted LRG1 for further verification. MiR‐497 and LRG1 expression in femoral head tissues and osteoblasts of osteoporosis rats were detected. TGF‐β1/Smads signalling pathway‐related factors were detected. MiR‐497 was poorly expressed while LRG1 was highly expressed and TGF‐β1/Smads signalling pathway activation was inhibited in osteoporosis. MiR‐497 up‐regulation or LRG1 down‐regulation activated TGF‐β1/Smads signalling pathway, promoted collagen type 1 synthesis and suppressed oxidative stress in femoral head tissues in osteoporosis. MiR‐497 restoration or LRG1 knockdown activated TGF‐β1/Smads signalling pathway, promoted viability and suppressed apoptosis of osteoblasts in osteoporosis. Our study suggests that miR‐497 up‐regulation or LRG1 down‐regulation promotes osteoblast viability and collagen synthesis via activating TGF‐β1/Smads signalling pathway, which may provide a novel reference for osteoporosis treatment.

Overexpressed microRNA-539-5p inhibits inflammatory response of neurons to impede the progression of cerebral ischemic injury by histone deacetylase 1

Several microRNAs (miRNAs or miRs) regulate cerebral ischemic injury outcomes; however, little is known about the role of miR-539-5p during cerebral ischemic injury or the postischemic state. Cerebral ischemic injury was modeled in vitro by exposing human cortical neurons to oxygen-glucose deprivation (OGD) and in vivo by occluding the middle cerebral artery (MCAO) in a rat model. The effects of miR-539-5p, histone deacetylase 1 (HDAC1), and early growth response 2 (EGR2) on cerebral ischemia were investigated using gain- and loss-of-function experiments. We identified changes in miR-539-5p, HDAC1, EGR2, and phosphorylated c-Jun NH₂-terminal kinase (JNK). The interaction among miR-539-5p, HDAC1, and EGR2 was determined by dual luciferase reporter gene assay, chromatin immunoprecipitation, and coimmunoprecipitation. We also investigated the effects on cell viability and apoptosis and changes in inflammatory cytokine expression and spatial memory on MCAO rats. miR-539-5p and EGR2 were poorly expressed, while HDAC1 was highly expressed in OGD-treated HCN-2 cells. miR-539-5p targeted HDAC1, while HDAC1 prevented acetylation of EGR2 resulting in its downregulation and subsequent activation of the JNK pathway. Overexpression of miR-539-5p or EGR2 or silencing HDAC1 improved viability and reduced apoptosis of OGD-treated HCN-2 cells in vitro. Furthermore, overexpression of miR-539-5p improved spatial memory, while decreasing cell apoptosis and inflammation in MCAO rats. Collectively, these data suggest that miR-539-5p targets HDAC1 to upregulate EGR2, thus blocking the JNK signaling pathway, by which cerebral ischemic injury is alleviated.

MicroRNA-592 suppresses the malignant phenotypes of thyroid cancer by regulating lncRNA NEAT1 and downregulating NOVA1

Numerous studies have demonstrated that various microRNAs (miRs) are aberrantly expressed in thyroid cancer and play critical roles in thyroid cancer malignancy. The aberrant expression of miR‑592 has frequently been reported in multiple human cancer types; however, its expression profile and functions in thyroid cancer remain poorly understood. Reverse transcription‑quantitative polymerase chain reaction was carried out to determine the expression profile of miR‑592 in thyroid cancer tissues and cell lines. The regulatory effects of miR‑592 upregulation on thyroid cancer cell proliferation, migration, and invasion in vitro, and tumor growth in vivo were investigated using a CCK‑8 assay, migration and invasion assays, and a xenograft tumor model, respectively. Furthermore, the mechanisms underlying miR‑592‑mediated suppression of the aggressive phenotypes of thyroid cancer cells were explored in detail. The results indicated that miR‑592 was significantly downregulated in thyroid cancer samples, and its downregulation was associated with lymph node metastasis and tumor‑node‑metastasis stage. Patients with thyroid cancer and low miR‑592 expression exhibited shorter overall survival than patients with high miR‑592 expression. Overexpression of miR‑592 resulted in decreased cell proliferation, migration, and invasion in thyroid cancer. In addition, neuro‑oncological ventral antigen 1 (NOVA1) was identified as a novel target gene of miR‑592 in thyroid cancer cells. Furthermore, ectopic NOVA1 expression may effectively abolish the tumor‑suppressing effects of miR‑592 overexpression in thyroid cancer cells. Notably, the lncRNA NEAT1 was proposed to function as a sponge of miR‑592 in thyroid cancer cells, thereby regulating NOVA1 expression. Finally, resuming miR‑592 expression significantly impaired thyroid cancer tumor growth in vivo. The results indicated that the NEAT1/miR‑592/NOVA1 pathway may play regulatory roles in thyroid cancer malignancy in vitro and in vivo. Our findings may provide novel insight into the pathogenesis of thyroid cancer. Therefore, this pathway may be an effective target for treating patients with this disease.