MicroRNA-342-3p Inhibits the Proliferation, Migration, and Invasion of Osteosarcoma Cells by Targeting Astrocyte-Elevated Gene-1 (AEG-1)

Fetal Brain-Derived Exosomal miRNAs from Maternal Blood: Potential Diagnostic Biomarkers for Fetal Alcohol Spectrum Disorders (FASDs)

Fetal alcohol spectrum disorders (FASDs) are leading causes of neurodevelopmental disability but cannot be diagnosed early in utero. Because several microRNAs (miRNAs) are implicated in other neurological and neurodevelopmental disorders, the effects of EtOH exposure on the expression of these miRNAs and their target genes and pathways were assessed. In women who drank alcohol (EtOH) during pregnancy and non-drinking controls, matched individually for fetal sex and gestational age, the levels of miRNAs in fetal brain-derived exosomes (FB-Es) isolated from the mothers' serum correlated well with the contents of the corresponding fetal brain tissues obtained after voluntary pregnancy termination. In six EtOH-exposed cases and six matched controls, the levels of fetal brain and maternal serum miRNAs were quantified on the array by qRT-PCR. In FB-Es from 10 EtOH-exposed cases and 10 controls, selected miRNAs were quantified by ddPCR. Protein levels were quantified by ELISA. There were significant EtOH-associated reductions in the expression of several miRNAs, including miR-9 and its downstream neuronal targets BDNF, REST, Synapsin, and Sonic hedgehog. In 20 paired cases, reductions in FB-E miR-9 levels correlated strongly with reductions in fetal eye diameter, a prominent feature of FASDs. Thus, FB-E miR-9 levels might serve as a biomarker to predict FASDs in at-risk fetuses.

Dysregulation of MicroRNAs Derived from Plasma Extracellular Vesicles in Schizoaffective Disorder

The association between peripheral blood extracellular vesicles (EVs)-derived miRNAs (EVs-miRNAs) and neuropsychiatric diseases has been extensively studied. However, it remains largely unclear about the expression profile of EVs-miRNAs in schizoaffective disorder (SAD) patients. In our study, we isolated the EVs from plasma samples of patients and healthy controls, and then analyzed the expression profiles of EVs-miRNAs through small RNA sequencing. Our results identified 32 differentially expressed (DE) miRNAs (25 upregulated and 7 downregulated) in SAD patients. A module containing 42 miRNAs closely related to SAD was identified by weighted gene co-expression network analysis (WGCNA), among which has-miR-15b-5p, has-miR-301a-3p, has-miR-342-3p, has-miR-219b-5p, and has-miR-145-5p were identified as hub miRNAs. The enrichment analysis showed that the target genes of these 42 miRNAs were significantly enriched in multiple pathways related to neuropathology and located at synapses. A total of 6 DE miRNAs (has-miR-7-5p, has-miR-144-3p, has-miR-155-5p, has-miR-342-3p, has-miR-342-5p, and has-miR-487b-3p) associated with SAD were selected for qRT-PCR verification. The level of has-miR-342-3p in SAD patients was downregulated, and hsa-miR-155-5p was upregulated. Our findings support the hypothesis that dysregulation of EVs-miRNAs in plasma might be involved in the underlying neuropathology of SAD through several biological pathways and provide important preliminary evidence supporting the use of EVs-miRNAs as potential novel biomarkers in SAD.

Expression patterns of AEG-1 in the normal brain

Astrocyte elevated gene-1 (AEG-1) is a well-known oncogene implicated in various types of human cancers, including brain tumors. Recently, AEG-1 has also been reported to play pivotal roles in glioma-associated neurodegeneration and neurodegenerative diseases like Parkinson's disease and amyotrophic lateral sclerosis. However, the normal physiological functions and expression patterns of AEG-1 in the brain are not well understood. In this study, we investigated the expression patterns of AEG-1 in the normal mouse brain and found that AEG-1 is widely expressed in neurons and neuronal precursor cells, but little in glial cells. We observed differential expression levels of AEG-1 in various brain regions, and its expression was mainly localized in the cell body of neurons rather than the nucleus. Additionally, AEG-1 was expressed in the cytoplasm of Purkinje cells in both the mouse and human cerebellum, suggesting its potential role in this brain region. These findings suggest that AEG-1 may have important functions in normal brain physiology and warrant further investigation. Our results may also shed light on the differential expression patterns of AEG-1 in normal and pathological brains, providing insights into its roles in various neurological disorders.

Molecular biology of microRNA-342 during tumor progression and invasion

Cancer is considered as one of the main causes of human deaths and health challenges in the world. Various factors are involved in the high death rate of cancer patients, including late diagnosis and drug resistance that result in treatment failure and tumor recurrence. Invasive diagnostic methods are one of the main reasons of late tumor detection in cancer patients. Therefore, it is necessary to investigate the molecular tumor biology to introduce efficient non-invasive markers. MicroRNAs (miRNAs) are involved in regulation of the cellular mechanisms such as cell proliferation, apoptosis, and migration. MiRNAs deregulations have been also frequently shown in different tumor types. Here, we discussed the molecular mechanisms of miR-342 during tumor growth. MiR-342 mainly functions as a tumor suppressor by the regulation of transcription factors and signaling pathways such as WNT, PI3K/AKT, NF-kB, and MAPK. Therefore, miR-342 mimics can be used as a reliable therapeutic strategy to inhibit the tumor cells growth. The present review can also pave the way to introduce the miR-342 as a non-invasive diagnostic/prognostic marker in cancer patients.

Modulation of immunosuppressive cells and noncoding RNAs as immunotherapy in osteosarcoma

The most common bone cancer is osteosarcoma (OS), which mostly affects children and teenagers. Early surgical resection combined with chemotherapy significantly improves the prognosis of patients with OS. Existing chemotherapies have poor efficacy in individuals with distant metastases or inoperable resection, and these patients may respond better to novel immunotherapies. Immune escape, which is mediated by immunosuppressive cells in the tumour microenvironment (TME), is a major cause of poor OS prognosis and a primary target of immunotherapy. Myeloid-derived suppressor cells, regulatory T cells, and tumour-associated macrophages are the main immunosuppressor cells, which can regulate tumorigenesis and growth on a variety of levels through the interaction in the TME. The proliferation, migration, invasion, and epithelial-mesenchymal transition of OS cells can all be impacted by the expression of non-coding RNAs (ncRNAs), which can also influence how immunosuppressive cells work and support immune suppression in TME. Interferon, checkpoint inhibitors, cancer vaccines, and engineered chimeric antigen receptor (CAR-T) T cells for OS have all been developed using information from studies on the metabolic properties of immunosuppressive cells in TME and ncRNAs in OS cells. This review summarizes the regulatory effect of ncRNAs on OS cells as well as the metabolic heterogeneity of immunosuppressive cells in the context of OS immunotherapies.

Quercetin Inhibits Tumorigenesis of Colorectal Cancer Through Downregulation of hsa_circ_0006990

Quercetin can significantly inhibit the progression of colorectal cancer (CRC). However, its specific mechanism remains largely unclear. In this study, we aimed to explore the correlation among quercetin, tumour-associated macrophages (TAMs) and circular RNAs (circRNAs) in the progression of CRC and to present a novel strategy for the treatment of CRC. In this study, we revealed that quercetin could suppress the autophagy of M2-TAMs and induced their differentiation into M1-TAMs, by which quercetin significantly reversed the inhibition of M2-TAMS on CRC cell apoptosis and the promotion of M2-TAMS on CRC cell proliferation. Moreover, quercetin could promote the expression of downregulated hsa_circ_0006990 in CRC cells co-cultured with M2-TAMs, and the overexpression of hsa_circ_0006990 significantly reversed the anti-tumour effect of quercetin on CRC. Furthermore, we found quercetin can notably suppress the progression of CRC via mediation of the hsa_circ_0006990/miR-132-3p/MUC13 axis. In conclusion, our results suggested that quercetin inhibits the tumorigenesis of CRC via inhibiting the polarisation of M2 macrophages and downregulating hsa_circ_0006990. Our study provides useful insights for those exploring new methods of treating CRC.

Advances in the Biological Functions and Mechanisms of miRNAs in the Development of Osteosarcoma

Osteosarcoma is one of the most common primary malignant bone tumors, mainly occurring in children and adolescents, and is characterized by high morbidity and poor prognosis. MicroRNAs, a class of noncoding RNAs consisting of 19 to 25 nucleotides, are involved in cell proliferation, invasion, metastasis, and apoptosis to regulate the development and progression of osteosarcoma. Studies have found that microRNAs are closely related to the diagnosis, treatment, and prognosis of osteosarcoma patients and have an important role in improving drug resistance in osteosarcoma. This paper reviews the role of microRNAs in the pathogenesis of osteosarcoma and their clinical value, aiming to provide a new research direction for diagnosing and treating osteosarcoma and achieving a better prognosis.

Long non-coding RNA ASMTL-AS1 deteriorates the oncogenicity of osteosarcoma by decoying microRNA-342-3p and consequently raising ADAM9 expression

BACKGROUND

Till now, little is known regarding expression pattern and specific roles of lncRNA ASMTL antisense RNA 1 (ASMTL-AS1) in osteosarcoma (OS). Therefore, our current research measured the expression of ASMTL-AS1 in OS, unveiled the roles of ASMTL-AS1 in the modulation of malignant characteristics of OS, and identified the downstream mechanism.

METHODS

The regulatory actions of ASMTL-AS1 ablation in OS cells were explored utilizing loss-of-function experiments. Mechanistic studies were implemented utilizing bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation and rescue experiments.

RESULTS

ASMTL-AS1 expression in OS was elevated in both TCGA database and our own cohort. Interfering with ASMTL-AS1 restricted cell proliferation, migration and invasion while increasing cell apoptosis in vitro. Additionally, silencing ASMTL-AS1 blocked tumour growth in vivo. Mechanistically, ASMTL-AS1 could act as a competing endogenous RNA for microRNA-342-3p (miR-342-3p) and inhibit its activity in OS cells, consequently causing an increase in ADAM metallopeptidase domain 9 (ADAM9) levels. Furthermore, inhibiting miR-342-3p or upregulating ADAM9 abated silenced ASMTL-AS1-induced antitumour activity in OS cells.

CONCLUSION

ASMTL-AS1 aggravated OS progression by regulating the miR-342-3p/ADAM9 axis.

Hsa_circ_0004674 promotes osteosarcoma doxorubicin resistance by regulating the miR-342-3p/FBN1 axis

Background

The occurrence of chemoresistance is a common problem in tumor treatment. Circular RNA (circRNA) has been confirmed to be related to tumor chemoresistance. However, the role and the underlying molecular mechanism of hsa_circ_0004674 in the chemoresistance of osteosarcoma (OS) are still unclear.

Methods

The expression of hsa_circ_0004674, miR-342-3p, and fibrillin-1 (FBN1) was determined by qRT-PCR. Cell counting kit 8 assay was used to evaluate the doxorubicin (DXR) resistance of cells. The proliferation and apoptosis of cells were measured using colony formation assay and flow cytometry. Western blot analysis was utilized to examine the protein levels of resistance markers, Wnt/β-catenin pathway markers and FBN1. The interaction between miR-342-3p and hsa_circ_0004674 or FBN1 was confirmed by dual-luciferase reporter assay and RNA pull-down assay. Moreover, animal experiments were performed to assess the effect of hsa_circ_0004674 silencing on the DXR sensitive of OS in vivo.

Results

The upregulated hsa_circ_0004674 was found in DXR-resistant OS tissues and cells. Knockdown of hsa_circ_0004674 could inhibit the DXR resistance of OS cells in vitro and promote the DXR sensitive of OS tumors in vivo. In addition, we discovered that hsa_circ_0004674 could sponge miR-342-3p, and miR-342-3p could target FBN1. MiR-342-3p inhibitor could reverse the inhibition effect of hsa_circ_0004674 knockdown on the DXR resistance of OS cells. Similarly, the suppressive effect of miR-342-3p on the DXR resistance of OS cells also could be reversed by FBN1 overexpression. Furthermore, we revealed that hsa_circ_0004674 silencing inhibited the activity of Wnt/β-catenin pathway by the miR-342-3p/FBN1 axis.

Conclusion

Hsa_circ_0004674 facilitated the DXR resistance of OS through Wnt/β-catenin pathway via regulating the miR-342-3p/FBN1 axis, suggesting that hsa_circ_0004674 was a promising target for the chemoresistance of OS.

Emerging Role and Clinicopathological Significance of AEG-1 in Different Cancer Types: A Concise Review

Tumor breakthrough is driven by genetic or epigenetic variations which assist in initiation, migration, invasion and metastasis of tumors. Astrocyte elevated gene-1 (AEG-1) protein has risen recently as the crucial factor in malignancies and plays a potential role in diverse complex oncogenic signaling cascades. AEG-1 has multiple roles in tumor growth and development and is found to be involved in various signaling pathways of: (i) Ha-ras and PI3K/AKT; (ii) the NF-κB; (iii) the ERK or mitogen-activated protein kinase and Wnt or β-catenin and (iv) the Aurora-A kinase. Recent studies have confirmed that in all the hallmarks of cancers, AEG-1 plays a key functionality including progression, transformation, sustained angiogenesis, evading apoptosis, and invasion and metastasis. Clinical studies have supported that AEG-1 is actively intricated in tumor growth and progression which includes esophageal squamous cell, gastric, colorectal, hepatocellular, gallbladder, breast, prostate and non-small cell lung cancers, as well as renal cell carcinomas, melanoma, glioma, neuroblastoma and osteosarcoma. Existing studies have reported that AEG-1 expression has been induced by Ha-ras through intrication of PI3K/AKT signaling. Conversely, AEG-1 also activates PI3K/AKT pathway and modulates the defined subset of downstream target proteins via crosstalk between the PI3K/AKT/mTOR and Hedgehog signaling cascade which further plays a crucial role in metastasis. Thus, AEG-1 may be employed as a biomarker to discern the patients of those who are likely to get aid from AEG-1-targeted medication. AEG-1 may play as an effective target to repress tumor development, occlude metastasis, and magnify the effectiveness of treatments. In this review, we focus on the molecular mechanism of AEG-1 in the process of carcinogenesis and its involvement in regulation of crosstalk between the PI3K/AKT/mTOR and Hedgehog signaling. We also highlight the multifaceted functions, expression, clinicopathological significance and molecular inhibitors of AEG-1 in various cancer types.

A Review of AEG-1 Oncogene Regulating MicroRNA Expression in Colon Cancer Progression

MicroRNAs are a class of small non-coding RNAs that perform a crucial function in posttranscriptional gene regulation. Dysregulation of these microRNAs is associated with many types of cancer progression. In tumorigenesis, downregulated microRNAs might function as a tumour suppressor by repressing oncogenes, whereas overexpressed miRs might function as oncogenes by suppressing tumour suppressor. Similarly, Metadherin (also known as AEG-1/ LYRIC), is an oncogene, the levels of which are found to be very high in various cancers and play a crucial role in the proliferation of cells and invasion. Our review focuses on the study, which shows the alteration of microRNA expression profile and suppression of carcinogenesis when MTDH/AEG-1 is targeted. It summarises the studies where downregulation and upregulation of AEG-1 and microRNAs, respectively, alter the biological functions of the cell, such as proliferation and apoptosis. Studies have reported that AEG-1 can be direct or indirect target of microRNA, which could provide a new-insight to know the underlying molecular mechanism and might contribute to the progress of new therapeutic strategies for the disease.

AEG-1 deletion promotes cartilage repair and modulates bone remodeling-related cytokines via TLR4/MyD88/NF-κB inhibition in ovariectomized rats with osteoporosis

Background

Osteoporosis is a systemic skeletal disorder that can impact a variety of bones throughout the body. Astrocyte-elevated gene-1 (AEG-1) is involved in multiple pro-tumorigenic functions and participates in various inflammatory reactions. However, whether it has an impact on osteoporosis-related cartilage repair and bone remodeling remains unknown.

Methods

We utilized an ovariectomy mouse model with AEG-1 deletion to investigate the role of AEG-1 in osteoporosis. The mRNA level of AEG-1 was detected by RT-PCR, bone markers, bone volume/total volume (BV/TV), trabecular bone surface/bone volume (BSA/BV) and trabecular bone thickness (Tb. Th) were detected by micro computed tomography (µCT), bone injury was observed by HE and alcian blue staining. The contents of IL-6, IL-17, iNOS and IL-10 in peripheral blood of the three groups were detected by ELISA. The expression of OSX, coi1a1, OC, TLR4, MyD88 and NF-κB were detected by Western Blot.

Results

µCT revealed increased bone volume in the AEG-1 knockout (KO) ovariectomy (OVX) group compared to the wildtype (WT) OVX group 4 weeks after surgery, indicating restored bone formation after AEG-1 deletion. Flow sorting revealed that AEG-1 deletion inhibited the production of inflammatory factors. Western blot demonstrated activation of the TLR4/MyD88/NF-κB pathway after LPS exposure, which was reduced by AEG-1 deletion. AEG-1 deletion also improved lipopolysaccharide (LPS) induced adverse reactions.

Conclusions

Taken together, these findings indicate that AEG-1 deletion improves cartilage repair and bone remodeling during osteoporosis, which may partly occur through the inhibition of the TLR4/MyD88/NF-κB signaling pathway.

Bone Microenvironment and Osteosarcoma Metastasis

The bone microenvironment is an ideal fertile soil for both primary and secondary tumors to seed. The occurrence and development of osteosarcoma, as a primary bone tumor, is closely related to the bone microenvironment. Especially, the metastasis of osteosarcoma is the remaining challenge of therapy and poor prognosis. Increasing evidence focuses on the relationship between the bone microenvironment and osteosarcoma metastasis. Many elements exist in the bone microenvironment, such as acids, hypoxia, and chemokines, which have been verified to affect the progression and malignance of osteosarcoma through various signaling pathways. We thoroughly summarized all these regulators in the bone microenvironment and the transmission cascades, accordingly, attempting to furnish hints for inhibiting osteosarcoma metastasis via the amelioration of the bone microenvironment. In addition, analysis of the cross-talk between the bone microenvironment and osteosarcoma will help us to deeply understand the development of osteosarcoma. The cellular and molecular protagonists presented in the bone microenvironment promoting osteosarcoma metastasis will accelerate the exploration of novel therapeutic strategies towards osteosarcoma.

MiR-342-3p inhibits cell migration and invasion through suppressing forkhead box protein Q1 in ovarian carcinoma

Previous studies have shown that microRNAs are involved in the pathogenesis of ovarian carcinoma (OC). However, the abnormal expression and function of miR-342-3p have not been reported in OC. Therefore, this research was designed to explore its role in OC. In this study, qRT-PCR assay showed that the expression level of miR-342-3p was reduced in OC tissues and cell lines. Functionally, Transwell assay suggested that overexpression of miR-342-3p suppressed cell migration and invasion in OC. In addition, forkhead box protein Q1 (FOXQ1) was confirmed to be a direct target gene by luciferase activity assay. Furthermore, FOXQ1 was found to be upregulated and function as an oncogene in OC. More importantly, miR-342-3p was negatively correlated with FOXQ1 expression in OC tissues. Furthermore, overexpression of FOXQ1 could partially rescue inhibitory effect of miR-342-3p on cell migration and invasion in OC. In brief, we concluded that miR-342-3p inhibited migration and invasion of OC cells through suppressing FOXQ1 expression.

LncRNA LINC00313 Knockdown Inhibits Tumorigenesis and Metastasis in Human Osteosarcoma by Upregulating FOSL2 through Sponging miR-342-3p

PURPOSE

Osteosarcoma (OS) is the most common primary bone tumor, with high morbidity in infants and adolescents. Long noncoding RNA LINC00313 has been found to modulate papillary thyroid cancer tumorigenesis and to be dysregulate in lung cancer. However, the role of LINC00313 in OS has not yet been addressed.

MATERIALS AND METHODS

We evaluated mRNA and protein expression using real-time quantitative PCR and Western blotting. Cell proliferation was evaluated using MTT; apoptosis and autophagy were assessed with flow cytometry, Western blotting, and/or GFP-LC3 assay. Transwell assay was conducted to measure cell migration and invasion. Potential target sites for LINC00313 and miR-342-3p were predicted with starBase v.2.0 and TargetScan Human, and verified using luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down assay. In vivo, xenogeneic tumors were induced with U2OS and MG-63 cells, separately.

RESULTS

LINC00313 was upregulated and miR-342-3p was downregulated in OS tissues and cells. High expression of LINC00313 was associated with shorter overall survival. FOSL2 downregulation and miR-342-3p overexpression suppressed cell proliferation and migratory and invasive abilities while promoting apoptosis and autophagy, all of which were consistent with the effects of LINC00313 knockdown. miR-342-3p, sponged by LINC00313, inversely modulated FOSL2 by targeting MG-63 cells, and FOSL2 expression was positively controlled by LINC00313. LINC00313 knockdown suppressed tumor growth in vivo.

CONCLUSION

LINC00313 is upregulated in OS, and LINC00313 knockdown plays a vital anti-tumor role in OS cell progression through a miR-342-3p/FOSL2 axis. Our study suggests that LINC00313 may be a novel, promising biomarker for diagnosis and prognosis of OS.

CircSAMD4A regulates cell progression and epithelial‑mesenchymal transition by sponging miR‑342‑3p via the regulation of FZD7 expression in osteosarcoma

Osteosarcoma (OS) is a primary malignant tumor with a complex etiology. Therefore, research into the pathogenesis of osteosarcoma is considered a priority. Circular RNAs play important roles in cell metabolism and in the immune response and are closely associated with cancer treatment. However, research into the association of circular RNAs with osteosarcoma is limited. In the present study, CircSAMD4A was validated by RT‑qPCR and agarose gel electrophoresis. CircSAMD4A and miR‑342‑3p expression was detected by RT‑qPCR. The relative protein expression levels were measured by western blot analysis. MTT assay and flow cytometry were used to detect cell cytotoxicity and apoptosis, respectively. Transwell assay was applied to assess cell migration and invasion. Dual‑luciferase reporter assay was used to determine the association among CircSAMD4A, Frizzled‑7 (FZD7) and miR‑342‑3p. In vivo, subcutaneous tumor formation assay was performed in an experiment with nude mice. The results revealed that the expression levels of CircSAMD4A and FZD7 were upregulated, while those of miR‑342‑3p were downregulated in OS tissues and cells. The inhibition of CircSAMD4A suppressed cell progression and epithelial‑mesenchymal transition (EMT), and promoted cell apoptosis in OS. The reduction of miR‑342‑3p reversed the effects of CircSAMD4A downregulation on cell cytotoxicity, migration, invasion, apoptosis and EMT in OS, while FZD7 overexpression blocked the effect of miR‑342‑3p upregulation on OS progression. The suppressive effect of sh‑CircSAMD4A on tumor growth was thus verified in OS. Overall, the present study demonstrated that CircSAMD4A affected cell cytotoxicity, invasion, apoptosis, migration and EMT by regulating the miR‑342‑3p/FDZ7 axis in OS, thereby providing a novel regulatory mechanism and a potential therapeutic target for OS.

Knockdown of lncRNA SNHG16 suppresses multiple myeloma cell proliferation by sponging miR-342-3p

Background

Aberrant expression of long non-coding RNAs (lncRNAs) is closely associated with development and prognosis of human cancers. LncRNA SNHG16 is reportedly involved in human cancer; however, its roles in multiple myeloma (MM) remain unclear.

Methods

In this study, we investigated the function and molecular mechanisms of SNHG16 in MM. MM cells were transfected with si-SNHG16 or si-NC. SNHG16 expression levels was measured by qRT-PCR. Cell proliferation was monitored using the MTS. Flow cytometry assay was performed to measure the cell cycle and apoptosis. Luciferase reporter assay were performed to confirm the sponged miRNAs of SNHG16.

Results

SNHG16 expression was up-regulated in MM tissues. SNHG16 knockdown suppressed cell proliferation, arrested cell cycle transition from G1 to S phase, and promoted the apoptosis of MM cells. Moreover, SNHG16 knockdown promoted cleaved-Caspase-3, cleaved-Caspase-9, Foxa3a, and Bax expression, while markedly inhibiting CCND1, Bcl-2, Cyclin D1, PI3K, and p-AKT expression in MM cells. miR-342-3p was a direct target of SNHG16. SNHG16 knockdown significantly increased miR-342-3p expression in MM cells. Overexpression miR-342-3p markedly suppressed cell proliferation, arrested cell cycle transition from G1 to S phase, and promoted apoptosis of MM cells. Overexpression of miR-342-3p markedly promoted cleaved-Caspase-3/-9, Foxa3a, and Bax expression, and inhibited CCND1, Bcl-2, Cyclin D1, PI3K, and p-AKT expression in MM cells. Additionally, repression of miR-342-3p could rescue the effect of SNHG16 knockdown on MM cell proliferation, cycle arrest, apoptosis, and related protein expression.

Conclusion

Knockdown of lncRNA SNHG16 suppresses MM cell proliferation by sponging miR-342-3p, implicating SNHG16 as a novel therapeutic target for MM.

Oncogenic Role and Prognostic Value of MicroRNA-937-3p in Patients with Breast Cancer

Purpose

Breast cancer is the most common female tumor in the world. MicroRNA has been reported to play an important role in the progression of breast cancer. The purpose of this study was to explore the role of miR-937-3p in breast cancer.

Patients and methods

Expression of miR-937-3p in breast cancer tissues and serums was detected from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO) and patients' samples. Kaplan-Meier plotter identified the association between miR-937-3p and prognosis.

Results

The analysis of TCGA, GEO and qRT-PCR suggested that the level of miR-937-3p was increased in breast cancer tissues and serum compared with adjacent normal breast tissues and healthy persons, respectively. The decreased expression of miR-937-3p inhibited breast cancer proliferation, migration and invasion. CCRL2 was the target of miR-937-3p. In contrast to miR-937-3p, the level of CCRL2 was decreased in breast cancer tissues. Luciferase reporter assay revealed that miR-937-3p directly bound to the 3'-UTR of CCRL2. Double knockdown of CCRL2 and miR-937-3p promoted breast cancer cell proliferation, migration and invasion, suggesting that miR-937-3p promoted breast cancer cell proliferation, migration and invasion by targeting CCRL2. The Kaplan-Meier survival analysis suggested that breast cancer patients with high level of miR-937-3p or low level of CCRL2 had a reduced overall survival (OS).

Conclusion

miR-937-3p plays an important role in the diagnosis and prognosis of breast cancer. Inhibition of miR-937-3p expression may be a novel targeted therapy for breast cancer.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

MicroRNA-618 Directly Targets Metadherin mRNA To Suppress The Malignant Phenotype Of Osteosarcoma Cells By Reducing PTEN-AKT Pathway Output

Purpose

Dysregulation of microRNA-618 (miR-618) has been observed in multiple types of human cancer. However, whether miR-618 is implicated in osteosarcoma (OS) initiation and progression is still unclear. Hence, we measured the expression of miR-618 in OS tissues and cell lines. In addition, the roles of miR-618 and the mechanisms underlying its activities in OS cells were examined.

Methods

The expression status of miR-618 in OS was analyzed by reverse-transcription quantitative PCR. The regulatory roles of miR-618 overexpression in OS were explored by the Cell Counting Kit-8 assay, flow-cytometric analysis, Transwell cell migration and invasion assays, and a tumor xenograft experiment.

Results

The results revealed that the expression of miR-618 was notably lower in OS tissues and cell lines, and that the low miR-618 expression significantly correlated with the clinical stage and distant metastasis among patients with OS. Exogenous miR-618 expression significantly suppressed OS cell proliferation, migration, and invasion and induced apoptosis in vitro as well as slowed tumor growth in vivo. Mechanism investigation indicated that metadherin (MTDH) is a direct target gene of miR-618 in OS cells. A knockdown of MTDH mimicked the tumor-suppressive effects of miR-618 upregulation on OS cells. Notably, resumption of MTDH expression attenuated the miR-618–mediated reduction in OS cell growth and metastasis in vitro. In addition, miR-618 overexpression reduced the PTEN–AKT pathway output in OS cells both in vitro and in vivo through downregulation of MTDH.

Conclusion

To the best of our knowledge, this is the first study to show that miR-618 exerts crucial tumor-suppressive actions in OS pathogenesis by directly targeting MTDH mRNA and reducing PTEN–AKT pathway output. These results will help to elucidate the functions of miR-618 in OS and suggest that this miRNA may be investigated as a therapeutic target in this disease.

miR‑342‑3p suppresses cell migration and invasion in preeclampsia by targeting platelet‑derived growth factor receptor α

miR-342-3p expression was increased in the placentas of women with preeclampsia (PE) according to previous examinations; the mechanism underlying the development and progression of PE requires further investigation. The present study aimed to explore the mechanism and functionality of microRNA (miR)-342-3p in trophoblastic cells. The expression of miR-342-3p and platelet-derived growth factor receptor α (PDGFRA) in the placentas of 30 patients with PE and 30 normal controls was detected. In addition, HTR8/SVneo cells were transfected with miR-342-3p mimics, small interfering RNA (siR)-PDGFRA or their corresponding negative controls; then the proliferation, migration, invasion and the distribution of the cell cycle of these cells were analyzed. Additionally, a dual-luciferase reporter assay was performed. According to these analyses, the expression of miR-342-3p was significantly increased, while that of PDGFRA was significantly lower in the PE group compared with the normal group. Transfection with miR-342-3p mimics led to a significant decrease in cell proliferation, migration and invasion, and also affected the cell cycle. Furthermore, miR-342-3p mimics reduced the expression of PDGFRA; miR-342-3p overexpression also reduced the mRNA and protein levels of BCL-2 and Caspase-3. In addition, transfection of siR-PDGFRA exhibited similar effects to those of miR-342-3p mimics. Finally, PDGFRA was reported to be a direct target of miR-342-3p. In conclusion, miR-342-3p was proposed to inhibit the proliferation, migration, invasion and G1/S phase transition of HTR8/SVneo cells by suppressing PDGFRA. Our findings suggest that miR-342-3p may be a novel clinical indicator or prognostic marker for PE.

Metadherin: A Therapeutic Target in Multiple Cancers

Altered expression of many genes and proteins is essential for cancer development and progression. Recently, the affected expression of metadherin (MTDH), also known as AEG-1 (Astrocyte Elevated Gene 1) and Lyric, has been implicated in various aspects of cancer progression and metastasis. Elevated expression of MTDH/AEG-1 has been reported in many cancers including breast, prostate, liver, and esophageal cancers, whereas its expression is low or absent in non-malignant tissues. These expression studies suggest that MTDH may represent a potential tumor associated antigen. MTDH also regulates multiple signaling pathways including PI3K/Akt, NF-κB, Wnt/β-catenin, and MAPK which cooperate to promote the tumorigenic and metastatic potential of transformed cells. Several microRNA have also been found to be associated with the increased MTDH expression in different cancers. Increased MTDH levels were linked to the tumor chemoresistance making it an attractive novel therapeutic target. In this review, we summarize data on MTDH function in various cancers.

microRNA-342-3p targets FOXQ1 to suppress the aggressive phenotype of nasopharyngeal carcinoma cells

Background

microRNA (miR)-342–3p is frequently dysregulated in human cancers. In the present study, we aimed to explore the expression, prognostic significance, and biological relevance of miR-342-3p in nasopharyngeal carcinoma (NPC).

Methods

We examined miR-342-3p expression in 79 paired NPC specimens and corresponding normal tissues and analyzed its prognostic impact on overall survival of NPC patients. Gain- and loss-of-function experiments were conducted to determine the biological roles of miR-342-3p.

Results

Compared with matched normal nasopharyngeal tissues, miR-342-3p was significantly downregulated in NPC (P = 0.0038). Low miR-342-3p expression was significantly correlated with reduced overall survival (P = 0.0084). Ectopic expression of miR-342-3p significantly suppressed proliferation, colony formation, and invasion of NPC cells. In contrast, depletion of miR-342-3p facilitated NPC cell proliferation and invasion. In vivo xenograft studies confirmed that overexpression of miR-342-3p restrained the growth of NPC xenograft tumors. Mechanistically, FOXQ1 served as a functional target of miR-342-3p. There was a significantly negative correlation between miR-342-3p and FOXQ1 expression (r = − 0.487, P = 0.004) in NPC specimens. Overexpression of FOXQ1 rescued the inhibitory effects of miR-342-3p on NPC cell growth and invasion.

Conclusions

miR-342-3p downregulation predicts poor prognosis in NPC patients and shows suppressive activity against NPC growth and invasion through repression of FOXQ1. Restoration of miR-342-3p may represent a potential therapeutic strategy for NPC.

LINC00460 modulates KDM2A to promote cell proliferation and migration by targeting miR-342-3p in gastric cancer

Background

Increasing evidence has shown that long non-coding RNAs (lncRNAs) play important roles in the occurrence and development of human cancers. LINC00460, a novel tumor-related lncRNA, has been reported to be involved in several types of human malignancies. However, the role of LINC00460 in gastric cancer (GC) is still unclear. The present study aimed at exploring the biological role of LINC00460 in GC and illuminating the potential molecular mechanisms.

Methods

In this study, qRT-PCR, western blotting, MTT assay, and Transwell invasion assay were used to conduct relevant experimental analysis.

Results

Here, we found that LINC00460 was highly expressed in GC tissues and cell lines. Moreover, LINC00460 overexpression was found to promote GC cell proliferation, migration and invasion, whereas LINC00460 down-regulation significantly inhibited these processes. Notably, we confirmed that LINC00460 could up-regulate KDM2A expression by competitively binding to miR-342-3p in GC cells. Furthermore, the suppressive effects of LINC00460 down-regulation on GC cell proliferation, migration and invasion were partially reversed by a miR-342-3p inhibitor.

Conclusion

In summary, our findings provide evidence for LINC00460 as a potential therapeutic target in GC.

Blockade of NEAT1 represses inflammation response and lipid uptake via modulating miR-342-3p in human macrophages THP-1 cells

Atherosclerosis has been recognized as a chronic inflammation process induced by lipid of the vessel wall. Oxidized low-density lipoprotein (ox-LDL) can drive atherosclerosis progression involving macrophages. Recently, long noncoding RNAs (lncRNAs) have been reported to play critical roles in atherosclerosis development. In our current study, we focused on the biological roles of lncRNA NEAT1 in atherosclerosis progress. Here, we found that ox-LDL was able to trigger human macrophages THP-1 cells, a human monocytic cell line, apoptosis in a dose-dependent and time-dependent course. In addition, we observed that NEAT1 was significantly increased in THP-1 cells incubated with ox-LDL and meanwhile miR-342-3p was greatly decreased. Then, NEAT1 was silenced by transfection of small interfering RNA (siRNA) of NEAT1 into THP-1 cells. As exhibited, CD36, oil-red staining levels, total cholesterol (TC), total cholesterol (TG) levels and THP-1 cell apoptosis were obviously repressed by knockdown of NEAT1. Furthermore, inhibition of NEAT1 contributed to the repression of inflammation in vitro. Interleukin 6 (IL-6), IL-1β, cyclooxygenase-2 (COX-2) and tumour necrosis factor-alpha (TNF-α) protein levels were remarkably depressed by NEAT1 siRNA in THP-1 cells. By using bioinformatics analysis, miR-342-3p was predicted as a downstream target of NEAT1 and the correlation between them was confirmed in our study. Moreover, overexpression of miR-342-3p could also greatly suppress inflammation response and lipid uptake in THP-1 cells. Knockdown of NEAT1 and miR-342-3p mimics inhibited lipid uptake in THP-1 cells. In conclusion, we implied that blockade of NEAT1 repressed inflammation response through modulating miR-342-3p in human macrophages THP-1 cells and NEAT1 may offer a promising strategy to treat atherosclerotic cardiovascular diseases.

Inhibitory effect of icariin on osteosarcoma cell proliferation via the Wnt/β-catenin signaling pathway

Osteosarcoma, is a kind of malignant tumor derived from malignant interstitial cells. The pathogenesis of osteosarcoma remains unclear and despite use of chemotherapy drugs, resistance to these drugs affects the success of treatment. The present study was conducted to investigate the effects of icariin (ICA) on osteosarcoma cell proliferation and to investigate the role of the Wnt/β-catenin signaling pathway in the inhibition process of ICA on osteosarcoma cell proliferation. Different concentrations of ICA were selected to treat the osteosarcoma cell line 143B for 24 h, and then the onset concentration of ICA when it inhibited the growth of osteosarcoma cancer cell line 143B was detected via an MTT assay. The effect of ICA on the apoptosis of colon cancer cell line 143B under this concentration was detected using a flow cytometer. RNA in osteosarcoma cell line 143B was extracted, followed by reverse transcription. The expression levels of related and apoptotic proteins in the Wnt/β-catenin signaling pathway using ICA were detected by semi-quantitative PCR and western blot analysis, respectively. The expression quantities of vascular endothelial growth factor (VEGF) and MMP-9 were detected by ELISA. MTT assay showed that ICA inhibited the growth of 143B when its concentration was 5 µM (p<0.01). Flow cytometry showed that the number of apoptotic cells after ICA treatment was significantly higher than that in control group (p<0.01). RNA in osteosarcoma cell line 143B was extracted, followed by reverse transcription. Semi-quantitative PCR and western blot analysis revealed that the expression levels of p-GSK3β, β-catenin, c-Myc and cyclin D1 in cells after ICA treatment were significantly downregulated (p<0.01), while the expression level of caspase-3 was significantly increased (p<0.01). ELISA showed that the expression quantities of VEGF and MMP-9 were significantly decreased (p<0.01). Thus, ICA can significantly inhibit osteosarcoma cell proliferation and promote osteosarcoma cell apoptosis, which may be realized by affecting the expression of the Wnt/β-catenin signaling pathway and blocking the expression of related proteins.

T2DM inhibition of endothelial miR-342-3p facilitates angiogenic dysfunction via repression of FGF11 signaling

Understanding the function and molecular relevance of distinct miRNAs in endothelial cells (ECs) paves avenues for possible therapeutic intervention by targeting epigenetic mechanisms in vascular endothelial dysfunction, one of the major complications of type 2 diabetes mellitus (T2DM). MiR-342-3p, an obesity-associated miRNA, has recently been shown to be significantly upregulated in human angiosarcoma compared to benign hemangioma, indicating its potential involvement as a proangiogenic factor. Herein, we show that endothelial miR-342-3p expression was significantly compromised in T2DM organisms and this inhibition powerfully blocked vasculogenesis in vivo by repressing endothelial proliferation and migration. From a mechanistic standpoint, miR-342-3p promoted the transactivation of fibroblast growth factor 11 (FGF11) by directly targeting its 3' untranslated regions (3'UTRs). Functionally, overexpression of exogenous FGF11 successfully rescued miR-342-3p deficiency-impaired endothelial proliferation and migration. Thus, perturbation of miR-342-3p/FGF11 cascade by hyperinsulinemia plays a causative role in the induction of vascular dysfunction in T2DM. Overall, the current study underscore an endothelial facet of miR-342-3p, which may operate as a novel epigenetic integrator linking adipogenic homeostasis and angiogenesis.

Serum miR-342-3p is a novel diagnostic and prognostic biomarker for non-small cell lung cancer

Lung cancer is the leading cause of cancer-related mortality and non-small cell lung carcinoma (NSCLC) is the most common type. MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. Aberrant expression of miRNAs has been demonstrated to be a prominent feature in NSCLC. The aim of this study was to determine the potential clinical value of serum miR-342-3p in NSCLC. We first evaluated the miR-342-3p levels in NSCLC cell lines, culture media of NSCLC cell lines, and serum samples from NSCLC patients as well as in their respective controls. The associations between serum miR-342-3p levels and clinicopathological parameters as well as clinical outcome were then determined. miR-342-3p expression was significantly downregulated in NSCLC cell lines, culture media of NSCLC cell lines, and the serum samples from NSCLC patients compared to their controls. Serum miR-342-3p discriminated NSCLC patients from healthy individuals. Low expression of serum miR-342-3p was significantly associated with advanced TNM stage and positive lymph node metastasis. In addition, NSCLC patients in the low serum miR-342-3p expression group had remarkably shorter overall survival than those in the high serum miR-342-3p expression group. Serum miR-342-3p was shown to be an independent prognosis factor. In conclusion, serum miR-342-3p might be a promising biomarker for NSCLC that can be used to improve diagnosis and prognosis.

miR-342-3p suppresses hepatocellular carcinoma proliferation through inhibition of IGF-1R-mediated Warburg effect

Background

Insulin-like growth factor-1 receptor (IGF-1R) is a well-studied oncogenic factor that promotes cell proliferation and energy metabolism and is overexpressed in numerous cancers including hepatocellular carcinoma (HCC). Aerobic glycolysis is a hallmark of cancer, and drugs targeting its regulators, including IGF-1R, are being developed. However, the mechanisms of IGF-1R inhibition and the physiological significance of the IGF-1R inhibitors in cancer cells are unclear.

Materials and methods

Cell proliferation was evaluated by cell counting Kit-8 and colony formation assay. Western blot and real-time PCR were accordingly used to detect the relevant proteins, miRNA and gene expression. Luciferase reporter assays were used to illustrate the interaction between miR-342-3p and IGF-1R. The effect of miR-342-3p on glycolysis was determined by glucose uptake, ATP concentration, lactate generation, extracellular acidification rate and oxygen consumption rate assays. In vivo, subcutaneous tumor formation assay and PET were performed in nude mice.

Results

In this study, we demonstrate that by directly targeting the 3′-UTR (3′-untranslated regions) of IGF-1R, microRNA-342-3p (miR-342-3p) suppresses IGF-1R-mediated PI3K/AKT/GLUT1 signaling pathway both in vitro and in vivo. Through suppression of IGF-1R, miR-342-3p dampens glycolysis by decreasing glucose uptake, lactate generation, ATP production, and extracellular acidification rate (ECAR), and increasing oxygen consumption rate (OCR) in hepatoma cells. Importantly, glycolysis regulated by miR-342-3p is critical for its regulating HCC growth both in vitro and in vivo.

Conclusion

Our findings provide clues regarding the role of miR-342-3p as a tumor suppressor in liver cancer mainly through the inhibition of IGF-1R. Targeting IGF-1R by miR-342-3p could be a potential therapeutic strategy in liver cancer.

MicroRNA-342 Prohibits Proliferation and Invasion of Melanoma Cells by Directly Targeting Zinc-Finger E-Box-Binding Homeobox 1

As documented in numerous studies, microRNAs (miRNAs) play key roles in various biological processes associated with melanoma occurrence and development. In this study, we found that miRNA-342 (miR-342) was significantly downregulated in melanoma tissues and cell lines. Additionally, the ectopic expression of miR-342 prohibited the cell proliferation and invasion of melanoma. Moreover, zinc-finger E-box-binding homeobox 1 (ZEB1) was identified as a direct target gene of miR-342 in melanoma. Similar with the results induced by miR-342 overexpression, ZEB1 knockdown attenuated cell proliferation and invasion in melanoma. Furthermore, the restoration of ZEB1 expression reversed the suppressive effects of miR-342 on the proliferation and invasion of melanoma cells. These findings suggest that miR-342 may play tumor-suppressing roles in melanoma, at least partially, by directly inhibiting ZEB1 expression. Therefore, miR-342 may be developed as a potential candidate for the treatment of patients with this aggressive type of cancer.

Epigenetic silencing of EVL/miR-342 in multiple myeloma

miR-342-3p, localized to 14q32, is a tumor suppressor miRNA implicated in multiple cancers. As the promoter region of its host gene, EVL, is embedded in a CpG island, we postulated that miR-342-3p is an intronic miRNA co-regulated with its host gene by promoter DNA methylation in multiple myeloma (MM). By methylation-specific polymerase chain reaction, verified by quantitative bisulfite pyrosequencing, methylation of EVL/miR-342 was absent in all healthy controls (n = 10) and 12 of 15 (80%) human myeloma cell lines (HMCLs), but partially methylated in 3 of 15 (20%) HMCLs, including KMS-12-PE, OCI-MY5, and RPMI-8226R. In HMCLs, by real-time quantitative reverse transcription-polymerase chain reaction, methylation of EVL/miR-342 correlated with lower expression of both EVL (P = 0.013) and miR-342-3p (P = 0.023). Moreover, in KMS-12-PE and RPMI-8226R cells, both partially methylated for EVL/miR-342, 5-AzadC treatment led to demethylation of EVL/miR-342 and re-expression of miR-342-3p. Upon removal of 5-AzadC, continuous culture resulted in restoration of EVL/miR-342 methylation and downregulation of miR-342-3p. In primary samples, methylation of EVL/miR-342 was detected in 1 of 18 (5.6%) monoclonal gammopathy of undetermined significance (MGUS), 8 of 63 (12.7%) diagnostic MM, and 5 of 30 (16.7%) relapsed MM. EVL/miR-342 methylation was preferentially detected in IgD MM but not found to impact survival. Collectively, in MM, miR-342-3p is an intronic miRNA regulated by promoter DNA methylation of its host gene, EVL, in a tumor-specific manner. Methylation of EVL/miR-342 was present in consecutive stages of myelomagenesis including MGUS, diagnostic MM, and relapsed MM.

Expression profiling of microRNAs in human bone tissue from postmenopausal women

Bone tissue is composed of several cell types, which express their own microRNAs (miRNAs) that will play a role in cell function. The set of total miRNAs expressed in all cell types configures the specific signature of the bone tissue in one physiological condition. The aim of this study was to explore the miRNA expression profile of bone tissue from postmenopausal women. Tissue was obtained from trabecular bone and was analyzed in fresh conditions (n = 6). Primary osteoblasts were also obtained from trabecular bone (n = 4) and human osteoclasts were obtained from monocyte precursors after in vitro differentiation (n = 5). MicroRNA expression profiling was obtained for each sample by microarray and a global miRNA analysis was performed combining the data acquired in all the microarray experiments. From the 641 miRNAs detected in bone tissue samples, 346 (54%) were present in osteoblasts and/or osteoclasts. The other 46% were not identified in any of the bone cells analyzed. Intersection of osteoblast and osteoclast arrays identified 101 miRNAs shared by both cell types, which accounts for 30-40% of miRNAs detected in these cells. In osteoblasts, 266 miRNAs were detected, of which 243 (91%) were also present in the total bone array, representing 38% of all bone miRNAs. In osteoclasts, 340 miRNAs were detected, of which 196 (58%) were also present in the bone tissue array, representing 31% of all miRNAs detected in total bone. These analyses provide an overview of miRNAs expressed in bone tissue, broadening our knowledge in the microRNA field.

Profiling microRNA from Brain by Microarray in a Transgenic Mouse Model of Alzheimer's Disease

MicroRNAs (miRNAs) are small noncoding RNAs, which regulate numerous cell functions by targeting mRNA for cleavage or translational repression, and have been found to play an important role in Alzheimer's disease (AD). Our study aimed to identify differentially expressed miRNAs in AD brain as a reference of potential therapeutic miRNAs or biomarkers for this disease. We used amyloid precursor protein (APP) and presenilin 1 (PS1) double transgenic mice and age-matched wild-type (WT) littermates to determine the expression of miRNAs in the brain. MiRNAs were profiled by microarray, and differentially expressed miRNAs underwent target prediction and enrichment analysis. Microarray analysis revealed 56 differentially expressed miRNAs in AD mouse brain, which involved 39 miRNAs that were significantly upregulated and 19 that were downregulated at different ages. Among those miRNAs, a total of 11 miRNAs, including miR-342-3p, miR-342-5p, miR-376c-3p, and miR-301b-3p, were not only conserved in human but also predicted to have targets and signaling pathways closely related to the pathology of AD. In conclusion, in this study, differentially expressed miRNAs were identified in AD brain and proposed as biomarkers, which may have the potential to indicate AD progression. Despite being preliminary, these results may aid in investigating pathological hallmarks and identify effective therapeutic targets.