miR-509-5p Inhibits the Proliferation and Invasion of Osteosarcoma by Targeting TRIB2

Human pulmonary artery smooth muscle cell dysfunction is regulated by miR-509-5p in hypoxic environment

Reportedly, dysfunction of human pulmonary arterial smooth muscle cells (PASMCs) is associated with the pathogenesis of pulmonary arterial hypertension (PAH). Herein, the role of miR-509-5p in hypoxia-induced PASMCs and the underlying mechanism were explored. PASMCs were cultured under both normoxia and hypoxia conditions. Quantitative real-time polymerase-chain reaction (qPCR) was employed for quantifying the expressions of miR-509-5p and DNMT1 mRNA in the serum of PAH patients and PASMCs. MiR-509-5p mimics and inhibitors were then, respectively, transfected into PAMSCs, and CCK-8 and Transwell assays were utilized to detect PASMCs' proliferation and migration. Flow cytometry was executed for evaluating PASMCs' apoptosis. Interrelation between miR-509-5p and DNMT1 was determined utilizing bioinformatics analysis and dual-luciferase reporter assay. Western blot assay was used to detect the expression of DNMT1 or SOD2. MiR-509-5p in serum samples of patients with PAH as well as hypoxia-induced PASMCs was significantly down-regulated, whereas DNMT1 was markedly up-regulated. MiR-509-5p mimics reduces the proliferation and migration of PASMCs, but promotes the apoptosis; conversely, miR-509-5p inhibitors exerted opposite effects. DNMT1 was identified as a target gene of miR-509-5p, and overexpression of DNMT1 reversed the biological functions of miR-509-5p in regulating the phenotypes of PAMSCs. MiR-509-5p up-regulated the expression of SOD2 by down-regulating DNMT1. MiR-509-5p regulates the proliferation, migration and apoptosis of PASMCs, and restoration of miR-509-5p may be a promising strategy to treat PAH.

Evaluation of the Expression of miR-486-3p, miR-548-3p, miR-561-5p and miR-509-5p in Tumor Biopsies of Patients with Oral Squamous Cell Carcinoma

Background and objective: Oral squamous cell carcinoma (OSCC) is the most common head and neck malignancy. Expression patterns of microRNAs (miRNAs) can direct us in identifying valuable biomarkers for the prognosis of different neoplasms. Inappropriate regulation of miRNAs during physiological procedures can result in malignancies including OSCC. The aim of the present study was to evaluate the expression of miR-486-3p, miR-561-5p, miR-548-3p, and miR-509-5p in tissue biopsy samples with and without OSCC. Materials and methods: This case-control study was conducted on 17 healthy and 17 OSCC tissue biopsy samples. The expression of miRNAs was assessed using quantitative real-time PCR (q-RT-PCR) after RNA extraction from normal and cancer tissues and cDNA synthesis. Results: The means of miRNA-486-3p, miR-561-5p, and miR-548-3p expression were significantly different between OSCC and control groups (p < 0.001), but there was no significant difference in means of miR-509-5p expression between OSCC and control groups (p = 0.179). Conclusions: The findings of this study revealed that the expression of miR-486-3p and miR-561-5p was significantly lower in cancer samples compared to normal tissue samples. On the other hand, miR-548-3p expression increased in the OSCC group compared to the control group.

MiR-509-3-5p inhibits colon cancer malignancy by suppressing GTSE1

BACKGROUND

The overarching goal of this research was to identify the effect of miR-509-3-5p on colon cancer (CC) and its interaction with potential target gene GTSE1 in CC.

METHODS

The miR-509-3-5p expression was ascertained after performing qRT-PCR analyses, and the ability of GTSE1 to influence this microRNA was detected after carrying out RNA pull-down assay. CCK-8 assay kit was first employed to determine the proliferation of the cells. To examine the migration and invasion level of HCT116 and SW480 cells, cell wound healing and transwell assay were later performed. After constructing luciferase reporter plasmids, luciferase reporter assay was used to confirm the impacts of miR-509-3-5p on GTSE1 in HCT116 and SW480 cells.

RESULTS

We found that miR-509-3-5p expression reduced in CC, and its overexpression inhibited the proliferation, migration and invasion of CC cells. We later discovered that miR-509-3-5p could target GTSE1 that was then proved to be an oncogene in CC.

CONCLUSION

Our study uncovered that miR-509-3-5p regulated CC malignancy by suppressing target gene GTSE1.

The Critical Role of TRIB2 in Cancer and Therapy Resistance

Simple Summary

The Tribbles proteins are members of CAMK Ser/Thr protein kinase family. They are evolutionary conserved pseudokinases found in most tissues of eukaryotic organisms. This ubiquitously expressed protein family is characterized by containing a catalytically deficient kinase domain which lacks amino acid residues required for the productive interaction with ATP and metal ions. Tribbles proteins exert their biological functions mainly through direct interaction with MAPKK and AKT proteins, therefore regulating important pathways involved in cell proliferation, apoptosis and differentiation. Due to the role of MAPKK and AKT signalling in the context of cancer development, Tribbles proteins have been recently considered as biomarkers of cancer progression. Furthermore, as the atypical pseudokinase domain retains a binding platform for substrates, Tribbles targeting provides an attractive opportunity for drug development.

Abstract

The Tribbles pseudokinases family consists of TRIB1, TRIB2, TRIB3 and STK40 and, although evolutionarily conserved, they have distinctive characteristics. Tribbles members are expressed in a context and cell compartment-dependent manner. For example, TRIB1 and TRIB2 have potent oncogenic activities in vertebrate cells. Since the identification of Tribbles proteins as modulators of multiple signalling pathways, recent studies have linked their expression with several pathologies, including cancer. Tribbles proteins act as protein adaptors involved in the ubiquitin-proteasome degradation system, as they bridge the gap between substrates and E3 ligases. Between TRIB family members, TRIB2 is the most ancestral member of the family. TRIB2 is involved in protein homeostasis regulation of C/EBPα, β-catenin and TCF4. On the other hand, TRIB2 interacts with MAPKK, AKT and NFkB proteins, involved in cell survival, proliferation and immune response. Here, we review the characteristic features of TRIB2 structure and signalling and its role in many cancer subtypes with an emphasis on TRIB2 function in therapy resistance in melanoma, leukemia and glioblastoma. The strong evidence between TRIB2 expression and chemoresistance provides an attractive opportunity for targeting TRIB2.

Association of sonic hedgehog signaling pathway genes IHH, BOC, RAB23a and MIR195-5p, MIR509-3-5p, MIR6738-3p with gastric cancer stage

Gastric cancer is the leading cause of cancer-related mortality worldwide. Given the importance of gastric cancer in public health, identifying biomarkers associated with disease onset is an important part of precision medicine. The hedgehog signaling pathway is considered as one of the most significant widespread pathways of intracellular signaling in the early events of embryonic development. This pathway contributes also to the maintenance of pluripotency of cancer stem cells pluripotency. In this study, we analyzed the expression levels of sonic hedgehog (Shh) signaling pathway genes IHH, BOC, RAB23a and their regulatory miRNAs including MIR-195-5p, MIR-509-3-5p, MIR-6738-3p in gastric cancer patients. In addition, the impact of infection status on the expression level of those genes and their regulatory miRNAs was investigated. One hundred samples taken from 50 gastric cancer patients (50 tumoral tissues and their adjacent non-tumoral counterparts) were included in this study. There was a significant difference in all studied genes and miRNAs in tumoral tissues in comparison with their adjacent non-tumoral counterparts. The lower expression of IHH, BOC, RAB23, miR-195-5p, and miR-6738-3p was significantly associated with more advanced cancer stage. Additionally, IHH upregulation was significantly associated with CMV infection (P < 0.001). Also, receiver operating characteristic (ROC) curve analysis indicated that mir-195 was significantly related to several clinicopathological features including tumor stage, grade, age, gender, and infection status of gastric cancer and can be considered as a potential diagnostic biomarker for gastric cancer. This study confirms the important role of Shh signaling pathway genes in gastric cancer tumorigenesis and their potential as novel molecular biomarkers and therapeutic targets.

Tribbles homolog 2 (Trib2), a pseudo serine/threonine kinase in tumorigenesis and stem cell fate decisions

The family of Tribbles proteins play many critical nonenzymatic roles and regulate a wide range of key signaling pathways. Tribbles homolog 2 (Trib2) is a pseudo serine/threonine kinase that functions as a scaffold or adaptor in various physiological and pathological processes. Trib2 can interact with E3 ubiquitin ligases and control protein stability of downstream effectors. This protein is induced by mitogens and enhances the propagation of several cancer cells, including myeloid leukemia, liver, lung, skin, bone, brain, and pancreatic. Thus, Trib2 can be a predictive and valuable biomarker for the diagnosis and treatment of cancer. Recent studies have illustrated that Trib2 plays a major role in cell fate determination of stem cells. Stem cells have the capacity to self-renew and differentiate into specific cell types. Stem cells are important sources for cell-based regenerative medicine and drug screening. Trib2 has been found to increase the self-renewal ability of embryonic stem cells, the reprogramming efficiency of somatic cells, and chondrogenesis. In this review, we will focus on the recent advances of Trib2 function in tumorigenesis and stem cell fate decisions.

Control of Cell Growth and Proliferation by the Tribbles Pseudokinase: Lessons from Drosophila

Simple Summary

Tribbles pseudokinases represent a sub-branch of the CAMK (Ca²⁺/calmodulin-dependent protein kinase) subfamily and are associated with disease-associated signaling pathways associated with various cancers, including melanoma, lung, liver, and acute leukemia. The ability of this class of molecules to regulate cell proliferation was first recognized in the model organism Drosophila and the fruit fly genetic model and continues to provide insight into the molecular mechanism by which this family of adapter molecules regulates both normal development and disease associated with corruption of their proper regulation and function.

Abstract

The Tribbles (Trib) family of pseudokinase proteins regulate cell growth, proliferation, and differentiation during normal development and in response to environmental stress. Mutations in human Trib isoforms (Trib1, 2, and 3) have been associated with metabolic disease and linked to leukemia and the formation of solid tumors, including melanomas, hepatomas, and lung cancers. Drosophila Tribbles (Trbl) was the first identified member of this sub-family of pseudokinases and shares a conserved structure and similar functions to bind and direct the degradation of key mediators of cell growth and proliferation. Common Trib targets include Akt kinase (also known as protein kinase B), C/EBP (CAAT/enhancer binding protein) transcription factors, and Cdc25 phosphatases, leading to the notion that Trib family members stand athwart multiple pathways modulating their growth-promoting activities. Recent work using the Drosophila model has provided important insights into novel facets of conserved Tribbles functions in stem cell quiescence, tissue regeneration, metabolism connected to insulin signaling, and tumor formation linked to the Hippo signaling pathway. Here we highlight some of these recent studies and discuss their implications for understanding the complex roles Tribs play in cancers and disease pathologies.

miR-138-5p suppresses glioblastoma cell viability and leads to cell cycle arrest by targeting cyclin D3

Although malignant glioblastoma (GBM) treatment has significantly improved in the past few decades, the prognosis of GBM remains unsatisfactory. MicroRNA (miR)-138-5p has been reported as a tumor suppressor in several types of human cancer; however, little is known about the function of miR-138-5p in GBM. The present study aimed to investigate the role of miR-138-5p in GBM as well as the underlying molecular mechanisms. The present study performed bioinformatics analysis, reverse transcription-quantitative (RT-q)PCR, western blotting, cell viability assays, colony formation assays, invasion assays and cell cycle analysis to investigate the biological function of miR-138-5p in both patient tissues and cell lines. In addition, miR-138-5p targets in GBM were predicted using Gene Expression Omnibus website and further validated by a dual luciferase reporter gene assay. The results revealed that miR-138-5p expression levels in patients with GBM from a Gene Expression Omnibus dataset were significantly downregulated. RT-qPCR analysis of miR-138-5p expression levels also revealed similar results in GBM tissues and cell lines. The upregulation of miR-138-5p expression levels using a mimic significantly inhibited the cell viability, colony formation and the G₀/G₁ to S progression in GBM cell lines, suggesting that miR-138-5p may be a tumor suppressor. Moreover, miR-138-5p was discovered to directly target cyclin D3 (CCND3), a protein that serves an important role in the cell cycle, and inhibited its expression. Finally, silencing CCND3 using small interfering RNA suppressed the viability of GBM cells. In conclusion, the results of the present study suggested that miR-138-5p may function as a tumor suppressor in GBM by targeting CCND3, indicating that miR-138-5p may be a novel therapeutic target for patients with GBM.

LncRNA ZEB1-AS1 promotes pancreatic cancer progression by regulating miR-505-3p/TRIB2 axis

Long noncoding RNAs (lncRNAs) are crucial regulatory factors in the development and progression of human malignancies. The purpose of this study was to investigate the potential mechanism of ZEB1-AS1 in pancreatic cancer (PC). The expression of ZEB1-AS1 in PC tissues and cells was assessed by RT-qPCR. The overall survival rate was evaluated using the Kaplan-Meier analysis. The association between ZEB1-AS1 and miR-505 was verified by dual-luciferase reporter assay. CCK-8 assay was employed to analyze PC cell viability. Transwell assay was employed to detect the migration and invasion of PC cells. Our results revealed that ZEB1-AS1 expression was significantly upregulated in PC tissues and cells, and the high expression of ZEB1-AS1 indicated the low overall survival rate in PC patients. Loss-of-function and gain-of-function assays indicated that knockdown of ZEB1-AS1 inhibited the cell viability, migration and invasion of PC cells, while overexpression of ZEB1-AS1 promoted PC cell progression. Moreover, ZEB1-AS1 upregulated TRIB2 expression via sponging miR-505. Finally, rescue assays demonstrated that TRIB2 overexpression partially abrogated the inhibitory effect of ZEB1-AS1 knockdown on the viability, migration and invasion of PC cells. These results confirmed that ZEB1-AS1 promoted the tumorigenesis of PC through the miR-505/TRIB2 axis, which indicated that ZEB1-AS1 might function as a biomarker for PC treatment and provide a new therapeutic direction in PC.