MicroRNA-124 inhibits proliferation, invasion, migration and epithelial-mesenchymal transition of cervical carcinoma cells by targeting astrocyte-elevated gene-1

miR-218-5p, miR-124-3p and miR-23b-3p act synergistically to modulate the expression of NACC1, proliferation, and apoptosis in C-33A and CaSki cells

Background

In cervical cancer (CC), miR-218-5p, -124-3p, and -23b-3p act as tumor suppressors. These miRNAs have specific and common target genes that modulate apoptosis, proliferation, invasion, and migration; biological processes involved in cancer.

Methods

miR-218-5p, -124-3p, and -23b-3p mimics were transfected into C-33A and CaSki cells, and RT-qPCR was used to quantify the level of each miRNA and NACC1. Proliferation was assessed by BrdU and apoptosis by Annexin V/PI. In the TCGA and The Human Protein Atlas databases, the level of NACC1 mRNA and protein (putative target of the three miRNAs) was analyzed in CC and normal tissue. The relationship of NACC1 with the overall survival in CC was analyzed in GEPIA2. NACC1 mRNA and protein levels were higher in CC tissues compared with cervical tissue without injury.

Results

An increased expression of NACC1 was associated with lower overall survival in CC patients. The levels of miR-218-5p, -124-3p, and -23b-3p were lower, and NACC1 was higher in C-33A and CaSki cells compared to HaCaT cells. The increase of miR-218-5p, -124-3p, and -23b-3p induced a significant decrease in NACC1 mRNA. The transfection of the three miRNAs together caused more drastic changes in the level of NACC1, in the proliferation, and in the apoptosis with respect to the individual transfections of each miRNA.

Conclusion

The results indicate that miR-218-5p, -124-3p, and -23b-3p act synergistically to decrease NACC1 expression and proliferation while promoting apoptosis in C-33A and CaSki cells. The levels of NACC1, miR-218-5p, -124-3p, and -23b-3p may be a potential prognostic indicator in CC.

MicroRNA-124 plays an inhibitory role in cutaneous squamous cell carcinoma cells via targeting SNAI2, an immunotherapy determinant

MicroRNAs (miRs) play multiple roles during cutaneous squamous cell carcinoma (CSCC) progression. Previous studies suggest miR-124 could inhibit cancer development in CSCC.

METHODS

Obtained 63 pairs of CSCC and adjacent tissues for analysis. Cultured HaCaT and two CSCC cell lines (A431 and SCL-1) in DMEM (10 % FBS). Transfected cells using Lipofectamine 2000 with various miR-124 mimics, inhibitors, or Snail family transcriptional repressor 2 (SNAI2) expression plasmid. Performed a series of assays, including real-time quantitative PCR, Western blot, CCK8, wound healing, transwell, and luciferase reporter gene assay, to examine the effects of miR-124 on CSCC cells.

RESULTS

An evident downregulation of miR-124 in CSCC tissues, which was related to advanced disease stage and nodal metastasis. Overexpressing miR-124 could reduce the proliferation, migration, and invasion abilities of CSCC cells. It was verified that miR-124 targets the SNAI2 in CSCC cells. Moreover, ectopic expression of SNAI2 rescued the suppressive effects on CSCC cells induced by miR-124 overexpression. Furthermore, miR-124 increased cell sensitivity to cisplatin. Besides, SNAI2 is a critical factor in the immune-related aspects of CSCC and its modulation may influence the response to immunotherapy.

CONCLUSION

We demonstrate that miR-124 inhibits CSCC progression through downregulating SNAI2, and thus it may be a molecular candidate for treating CSCC in the clinic.

MicroRNA (miR)-124: A Promising Therapeutic Gateway for Oncology

MicroRNA (miR) are a class of small non-coding RNA that are involved in post-transcriptional gene regulation. Altered expression of miR has been associated with several pathological conditions. MicroRNA-124 (miR-124) is an abundantly expressed miR in the brain as well as the thymus, lymph nodes, bone marrow, and peripheral blood mono-nuclear cells. It plays a key role in the regulation of the host immune system. Emerging studies show that dysregulated expression of miR-124 is a hallmark in several cancer types and it has been attributed to the progression of these malignancies. In this review, we present a comprehensive summary of the role of miR-124 as a promising therapeutic gateway in oncology.

miR-23b-3p, miR-124-3p and miR-218-5p Synergistic or Additive Effects on Cellular Processes That Modulate Cervical Cancer Progression? A Molecular Balance That Needs Attention

In cervical cancer (CC), miR-23b-3p, miR-124-3p, and miR-218-5p have been found to act as tumor suppressors by regulating cellular processes related to progression and metastasis. The objective of the present review is to provide an update on the experimental evidence about the role of miR-23b-3p, miR-124-3p, and miR-218-5p in the regulation of CC progression. Additionally, we present the results of a bioinformatic analysis that suggest that these miRNAs have a somewhat redundant role in the same cellular processes that may result in a synergistic effect to promote CC progression. The results indicate that specific and common target genes for miR-23b-3p, miR-124-3p, and miR-218-5p regulate proliferation, migration, apoptosis, and angiogenesis, all processes that are related to CC maintenance and progression. Furthermore, several target genes may regulate cancer-related signaling pathways. We found that a total of 271 proteins encoded by the target mRNAs of miR-23b-3p, miR-124-3p, or miR-218-5p interact to regulate the cellular processes previously mentioned, and some of these proteins are regulated by HPV-16 E7. Taken together, information analysis indicates that miR-23b-3p, miR-124-3p, and miR-218-5p may potentiate their effects to modulate the cellular processes related to the progression and maintenance of CC with and without HPV-16 involvement.

Comparison of Selected Non-Coding RNAs and Gene Expression Profiles between Common Osteosarcoma Cell Lines

Simple Summary

Osteosarcoma (OS) is a malignant tumour affecting mainly children and elderly people. Despite significant advances in cancer medicine, osteosarcoma patients’ survival is not improving. The primary treatment methods are established using in vitro models that rely upon the application of well-established cell lines, including U-2 OS, Saos-2 and MG-63. The molecular phenotype of these cell lines is still not fully outlined. Therefore, our study aimed to establish the expression profile of molecular markers related to osteosarcoma survival, progression and metastasis. Non-bone-related cells were used as a reference, i.e. HeLa cell line and human adipose-derived stromal cells (hASCs). Evaluated osteosarcoma cell lines showed characteristic phenotypes with unique patterns related to upregulation of MMP-7, MMP-14, BMP-7, miR-21-5p, miR-124-3p and downregulation of lncRNA MEG3. Our findings may facilitate the selection of the most reliable cellular model for pre-clinical investigations focused on developing new and satisfying methods of osteosarcoma therapy.

Abstract

Osteosarcoma (OS) is a bone tumour affecting adolescents and elderly people. Unfortunately, basic treatment methods are still underdeveloped, which has a high impact on the poor survivability of the patients. Studies designed to understand the underlying mechanisms of osteosarcoma development, as well as preclinical investigations aimed at establishing novel therapeutic strategies, rely significantly upon in vitro models, which apply well-established cell lines such as U-2 OS, Saos-2 and MG-63. In this study, the expression of chosen markers associated with tumour progression, metastasis and survival were identified using RT-qPCR. Levels of several onco-miRs (miR-21-5p, miR-124-3p, miR-223-3p and miR-320a-3p) and long non-coding RNA MEG3 were established. The mRNA expression of bone morphogenetic proteins (BMPs), including BMP-2, BMP-3, BMP-4, BMP-6, BMP-7, as well as their receptors: BMPR-IA, BMPR-IB and BMPR-II was also determined. Other tested markers included metalloproteinases, i.e., MMP-7 and MMP-14 and survivin (BIRC5), C-MYC, as well as CYCLIN D (CCND1). The analysis included comparing obtained profiles with transcript levels established for the osteogenic HeLa cell line and human adipose-derived stromal cells (hASCs). The tested OS cell lines were characterised by a cancer-related phenotype, such as increased expression of mRNA for BMP-7, as well as MMP-7 and MMP-14. Osteosarcoma cells differ considerably in miR-21-5p and miR-124-3p levels, which can be related to uncontrolled tumour growth. The comprehensive examination of osteosarcoma transcriptome profiles may facilitate the selection of appropriate cell models for preclinical investigations aimed at the development of new strategies for OS treatment.

Infection by High-Risk Human Papillomaviruses, Epithelial-to-Mesenchymal Transition and Squamous Pre-Malignant or Malignant Lesions of the Uterine Cervix: A Series of Chained Events?

Wound healing requires static epithelial cells to gradually assume a mobile phenotype through a multi-step process termed epithelial-to-mesenchymal transition (EMT). Although it is inherently transient and reversible, EMT perdures and is abnormally activated when the epithelium is chronically exposed to pathogens: this event deeply alters the tissue and eventually contributes to the development of diseases. Among the many of them is uterine cervical squamous cell carcinoma (SCC), the most frequent malignancy of the female genital system. SCC, whose onset is associated with the persistent infection of the uterine cervix by high-risk human papillomaviruses (HR-HPVs), often relapses and/or metastasizes, being resistant to conventional chemo- or radiotherapy. Given that these fearsome clinical features may stem, at least in part, from the exacerbated and long-lasting EMT occurring in the HPV-infected cervix; here we have reviewed published studies concerning the impact that HPV oncoproteins, cellular tumor suppressors, regulators of gene expression, inflammatory cytokines or growth factors, and the interactions among these effectors have on EMT induction and cervical carcinogenesis. It is predictable and desirable that a broader comprehension of the role that EMT inducers play in SCC pathogenesis will provide indications to flourish new strategies directed against this aggressive tumor.

Metadherin-mediated mechanisms in human malignancies

Metadherin (MTDH) has been recognized as a novel protein that is critical for the progression of multiple types of human malignancies. Studies have reported that MTDH enhances the metastatic potential of cancer cells by regulating multiple signaling pathways. miRNAs and various tumor-related proteins have been shown to interact with MTDH, making it a potential therapeutic target as well as a biomarker in human malignancies. MTDH plays a critical role in inflammation, angiogenesis, hypoxia, epithelial-mesenchymal transition and autophagy. In this review, we present the function and mechanisms of MTDH for cancer initiation and progression.

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.

MicroRNA124 and microRNA21-5p regulate migration, proliferation and differentiation of rat bone marrow mesenchymal stem cells

Mesenchymal stem cells (MSCs) are multipotent stromal cells that can be a useful source of cells for the treatment of many diseases, including neurologic diseases. The curative effect of MSCs relies mostly on cell’s capacity of migration, proliferation and differentiation. MicroRNAs (miRNAs) are small non-coding RNAs that play important roles on regulating various cell behaviors. Here, we report that miRNA-124 (miR124) and miRNA-21-5p (miR21-5p) display different regulatory roles on migration, proliferation and neuron differentiation of MSCs. MiR124 was shown greatly promoting MSCs migration and neuronal differentiation. MiR21-5p could significantly enhance the proliferation and neuronal differentiation ability of MSCs. MiR124 and miR21-5p synergistically promote differentiation of MSCs into neurons. Collectively, miR124 and miR21-5p can functionally regulate cell migration, proliferation and neuronal differentiation of MSCs. Therefore, miR124 and miR21-5p may be promising tools to improve transplantation efficiency for neural injury.

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.

miR-124-3p Suppresses the Invasiveness and Metastasis of Hepatocarcinoma Cells via Targeting CRKL

Abnormal expressions of microRNAs are involved in growth and progression of human cancers including hepatocellular carcinoma (HCC). An adaptor protein CRKL plays a pivotal role in HCC growth, whereas miR-124-3p downregulation is associated with clinical stage and the poor survival of patients. However, the relationship between miR-124-3p and CRKL and the molecular mechanisms through which they regulate HCC metastasis remains unclear. In the current work, we explored miR-124-3p and its correlation with CRKL expression in HCC patient tissues. We found that miR-124-3p deficiency is inversely co-related with CRKL overexpression in tumorous tissues of HCC patients, which was also consistent in HCCLM3 and Huh7 HCC cell lines. Target validation data shows that miR-124-3p directly targets CRKL. The overexpression of miR-124-3p reverses the CRKL expression at both mRNA and protein levels and inhibits the cell development, migration, and invasion. Mechanistic investigations showed that CRKL downregulation suppresses the ERK pathway and EMT process, and concomitant decrease in invasion and metastasis of HCC cells. The expressions of key molecules in the ERK pathway such as RAF, MEK, ERK1/2, and pERK1/2 and key promoters of EMT such as N-cadherin and vimentin were downregulated, whereas E-cadherin, a key suppression indicator of EMT, was upregulated. MiR-124-3p-mediated CRKL suppression led to BAX/BCL-2 increase and C-JUN downregulation, which inhibited the cell proliferation and promoted the apoptosis in HCC cells. Collectively, our data illustrates that miR-124-3p acts as an important tumor-suppressive miRNA to suppress HCC carcinogenesis through targeting CRKL. The miR-124-3p-CRKL axial regulated pathway may offer valuable indications for cancer research, diagnosis, and treatment.

The roles of microRNA in human cervical cancer

Although a potentially preventable disease, cervical cancer (CC) is the second most commonly diagnosed gynaecological cancer with at least 530,000 new cases annually, and the prognosis with CC is still poor. Studies suggest that aberrant expression of microRNA (miRNA) contributes to the progression of CC. As a group of small non-coding RNA with 18-25 nucleotides, miRNA regulate about one-third of all human genes. They function by repressing translation or inducing mRNA cleavage or degradation, including genes involved in diverse and important cellular processes, including cell cycling, proliferation, differentiation, and apoptosis. Results showed that misexpression of miRNA is closely related to the onset and progression of CC. This review will provide an overview of the function of miRNA in CC and the mechanisms involved in cervical carcinogenesis.

Natural killer T cell cytotoxic activity in cervical cancer is facilitated by the LINC00240/microRNA-124-3p/STAT3/MICA axis

Long noncoding RNAs play significant roles in diverse cancers. In this study, we found that LINC00240 expression was markedly increased in cervical cancer. Functional in vitro assays in cervical cancer cells showed that LINC00240 enhanced the growth, migration, and invasion of cervical cancer cells. The target of LINC00240 was confirmed as microRNA(miR)-124-3p. Inhibition of miR-124-3p significantly enhanced cervical cancer progression via targeting of STAT3, which is greatly activated in tumor-infiltrating immune cells. LINC00240 expression was able to induce STAT3 expression via sponging of miR-124-3p, and showed a positive association with STAT3 expression in cervical cancer tissues. MHC class I-related chain (MIC)-A plays a key role in activating natural killer T (NKT) cells and serves as a downstream target of STAT3. Here, MICA was inhibited by up-regulation of LINC00240, and could be rescued by STAT3 knockdown. In addition, LINC00240 overexpression suppressed the cytotoxic activity of NKT cells by affecting the STAT3/MICA axis. Subsequently, we found that LINC00240 expression promoted cervical cancer progression via induction of miR-124-3p/STAT3/MICA-mediated NKT cell tolerance. Considering these findings, we conclude that LINC00240 might be a novel target for cervical cancer.

The role of miRNAs in the invasion and metastasis of cervical cancer

Cervical cancer (CC) with early metastasis of the primary tumor results in poor prognosis and poor therapeutic outcomes. MicroRNAs (miRNAs) are small, noncoding RNA molecules that play a substantial role in regulating gene expression post-transcriptionally and influence the development and progression of tumors. Numerous studies have discovered that miRNAs play significant roles in the invasion and metastasis of CC by affecting specific pathways, including Notch, Wnt/β-catenin, and phosphoinositide-3 kinase (PI3K)-Akt pathways. miRNAs also effectively modulate the process of epithelial–mesenchymal transition. Many studies provide new insights into the role of miRNAs and the pathogenesis of metastatic CC. In this review, we will offer an overview and update of our present understanding of the potential roles of miRNAs in metastatic CC.

Competing endogenous RNA networks in cervical cancer: function, mechanism and perspective

In the past several years, competing endogenous RNAs (ceRNAs) have emerged as a potential class of post-transcriptional regulators that alter gene expression through a microRNA (miRNA)-mediated mechanism. An increasing number of studies have found that ceRNAs play important roles in tumorigenesis. Cervical cancer is one of the most common cancers in female malignancies. Despite advances in our understanding of this neoplasm, patients with advanced cervical cancer still have poor prognosis. There is an urgent need to provide a new insight on the mechanism of cervical cancer development and may be acted as new anticancer therapeutic strategies. Here, we review the ceRNA studies and coherent researches in cervical cancer, especially in long non-coding RNA (lncRNA) and miRNAs in order to broaden horizons into mechanisms, selection biomarkers for diagnosis as well as predicting prognosis, and targeting treatment for cervical cancer in the future.

MicroRNA-124 inhibits cell proliferation, invasion and migration by targeting CAV1 in bladder cancer

MicroRNAs (miRs) may have promotive or suppressive roles in various human cancers types, but the molecular mechanisms underlying the role of miR-124 in bladder cancer (BC) progression have remained largely elusive. In the present study, it was observed that miR-124 was significantly downregulated in BC tissues compared with that in adjacent non-neoplastic tissues. Furthermore, its expression was also reduced in several human BC cell lines (T24, HT-1376 and 5637) compared with that in the normal bladder epithelial SV-HUC-1 cell line. A low expression of miR-124 in BC patients was significantly associated with advanced malignancy and a poor prognosis. Caveolin 1 (CAV1) was identified as a novel target gene of miR-124, and the expression of CAV1 was negatively regulated by miR-124 in T24 cells. Furthermore, CAV1 was identified to be significantly upregulated in BC tissues and cell lines, and a negative correlation was observed between the expression of miR-124 and CAV1 in BC tissues. Furthermore, restoration of miR-124 expression significantly inhibited the proliferation, migration and invasion of T24 cells, and these effects were impaired following overexpression of CAV1. Taken together, the present results demonstrate that miR-124 has a suppressive role in the proliferation, migration and invasion of BC cells by targeting CAV1, which suggests that miR-124 is a potential therapeutic candidate for BC.

MiR-129 regulates growth and invasion by targeting MAL2 in papillary thyroid carcinoma

MAL2, a member of the MAL proteolipid family, is essential for raft-mediated transport. In this study, we investigated the roles and underlying mechanism of MAL2 in the development of papillary thyroid carcinoma (PTC). Up-regulation of MAL2 was found in human PTC tissues and significantly correlated with poor overall survival (OS). Knockdown of MAL2 dramatically suppressed PTC cell proliferation and invasion in vitro and inhibited tumor growth in vivo. We further found that miR-129 suppressed the expression of MLA through directly binding to the 3' untranslated region (3' UTR). While forced miR-129 expression suppressed growth and invasion of PTC cells, re-expression of MAL2 rescued these effects. Taken together, our data indicated that MAL2 acted as an oncogene and was negatively regulated by miR-129, supporting the potential therapeutic strategy against PTC by targeting miR-129-MAL2 axis.

MicroRNA-302 inhibits cell migration and invasion in cervical cancer by targeting DCUN1D1

MicroRNA serve crucial roles in a variety of human cancer types. The miR-302-367 cluster has been reported to suppress the proliferation of cervical carcinoma cells through the novel target AKT1; however, the molecular mechanism of miR-302 in cervical cancer metastasis remains unclear. The present study aimed to investigate the clinical significance of miR-302-3p expression in cervical cancer, and to examine the regulatory mechanism of miR-302-3p in the malignant phenotypes of cervical cancer cells. The present data indicated that miR-302-3p was significantly downregulated in cervical cancer tissues compared with the level in adjacent non-tumor tissues, and low expression of miR-302-3p was significantly associated with node metastasis, advanced clinical stage, and poor prognosis in patients with cervical cancer. Restoration of miR-302-3p expression caused a significant reduction in cervical cancer cell migration and invasion. Defective in cullin neddylation 1 domain containing 1 (DCUN1D1) was identified as a novel target gene of miR-302-3p, and miR-302-3p negatively regulated the mRNA and protein expression of DCUN1D1 in cervical cancer HeLa cells. Additionally, overexpression of DCUN1D1 rescued the effects of miR-302-3p on the migration and invasion of cervical cancer cells. Furthermore, DCUN1D1 was upregulated in cervical cancer tissues compared with the levels in adjacent tissues, and its high expression was associated with node metastasis, advanced clinical stage, and shorter survival time in patients with cervical cancer. Notably, a negative correlation between miR-302-3p and DCUN1D1 expression in cervical cancer tissues was observed. Taken together, the present study suggests that miR-302-3p serves a suppressive role in cervical cancer metastasis, partly at least, via directly targeting DCUN1D1. Therefore, miR-302-3p/DCUN1D1 may be a potential therapeutic target for cervical cancer treatment.

Downregulation of microRNA-216b contributes to glioma cell growth and migration by promoting AEG-1-mediated signaling

Accumulating evidence indicates microRNA-216b (miR-216b) plays an important role in the development and progression of various cancers. However, little is known about the function of miR-216b in gliomas. In this study, we aimed to investigate the expression level and functional significance of miR-216b in gliomas. We found that miR-216b was significantly downregulated in glioma specimens and cell lines. Overexpression of miR-216b suppressed the growth and migration of glioma cells, while miR-216b inhibition showed the opposite effects. Astrocyte elevated gene-1 (AEG-1) was predicted as a potential target gene of miR-216b by bioinformatics analysis. A dual-luciferase reporter assay showed that miR-216b could directly target the 3'-untranslated region of AEG-1. RT-qPCR and western blot analysis showed that miR-216 negatively regulated AEG-1 expression in glioma cells. Correlation analysis revealed an inverse correlation between miR-216b and AEG-1 in clinical glioma specimens. miR-216b also regulated the activation of nuclear factor-κB and Wnt signaling in glioma cells. Moreover, restoration of AEG-1 expression partially reversed the inhibitory effect of miR-216b overexpression on glioma cell growth and migration. Overall, these results revealed a tumor suppressive role of miR-216b in glioma tumorigenesis, and identified AEG-1 as a target gene of miR-216b action. Our study suggests that miR-216b can be potentially targeted for the development of novel therapies for gliomas.

MicroRNA‑195 inhibits cell proliferation, migration and invasion by targeting defective in cullin neddylation 1 domain containing 1 in cervical cancer

MicroRNAs (miRs), a class of small non-coding RNAs, have been demonstrated to perform promoting or suppressive roles in various types of human malignancy. Deregulation of miR-195 has been observed in numerous types of human cancer, including cervical cancer; however, the detailed molecular mechanism of miR-195 underlying the malignant progression of cervical cancer remains largely unclear. In the present study, miR-195 was significantly down-regulated in cervical cancer tissue samples compared with adjacent non-tumor tissue samples, and the reduced expression level of miR-195 was associated with node metastasis and an advanced clinical stage in cervical cancer. Furthermore, the patients with low miR-195 expression levels demonstrated shorter survival times when compared with those with high miR-195 expression levels. In vitro experiments indicated that miR-195 exerted suppressive effects on the proliferation, migration and invasion of cervical cancer cells. Luciferase reporter gene assay identified defective in cullin neddylation 1 domain containing 1 (DCUN1D1) as a novel target gene of miR-195 and the expression level of DCUN1D1 was identified to be negatively regulated by miR-195 in cervical cancer cells. DCUN1D1 was significantly upregulated in cervical cancer, with a negative correlation to miR-195 expression. Furthermore, upregulation of DCUN1D1 was associated with the malignant progression and poor prognosis of cervical cancer. DCUN1D1 overexpression attenuated the suppressive effects of miR-195 on the malignant phenotypes of cervical cancer cells. Notably, the expression levels of miR-195 were significantly lower in HeLa [human papilloma virus (HPV)18⁺] and SiHa (HPV16⁺) cells compared with those in C33A (HPV⁻) cells, and knockdown of E6 using small interfering RNA significantly increased the miR-195 expression while the DCUN1D1 expression level was reduced in HeLa and SiHa cells. Thus, these findings indicate that miR-195 exerts a suppressive role in cervical cancer by targeting DCUN1D1. Therefore, miR-195 may present as a potential therapeutic candidate for cervical cancer.

microRNA-23a promotes cell growth and metastasis in gastric cancer via targeting SPRY2-mediated ERK signaling

microRNAs (miRs) serve important roles in various human cancer types. Recently, miR-23a has been indicated as an oncogene in gastric cancer, but the underlying mechanism remains unclear. In the present study, reverse transcription-quantitative polymerase chain reaction and western blot analysis was used to explore the effects of miR-23a in gastric cancer. Additionally, cell proliferation, migration and invasion were examined using an MTT assay, wound healing assay and Transwell assay, respectively. Furthermore, a luciferase reporter gene assay was used to confirm the target association. It was determined that miR-23a was significantly upregulated in gastric cancer tissues and cell lines compared with adjacent tissues, and a normal gastric epithelial cell line. Furthermore, its upregulation was significantly associated with cancer progression and poor prognosis of patients. Knockdown of miR-23a caused a notable reduction in the proliferation, migration and invasion of gastric cancer AGS cells. Sprouty homolog 2 (SPRY2) was then predicted to be target gene of miR-23a. A luciferase reporter gene assay data demonstrated that miR-23a has the ability to directly bind to the 3′-untranslational region of SPRY2 mRNA. Further investigation demonstrated that SPRY2 was significantly downregulated in gastric cancer tissues and cell lines, and the protein expression of SPRY2 was negatively regulated by miR-23a in AGS cells. Furthermore, knockdown of SPRY2 reduced the suppressive effects of miR-23a inhibition in AGS cell proliferation, migration and invasion. In addition, the activity of extracellular signal-regulated kinase (ERK) signaling was also inhibited by the miR-23a/SPRY2 knockdown in AGS cells. The present study indicated that miR-23a serves a promoting role in gastric cancer via targeting SPRY2 and downstream ERK signaling.

MicroRNA-124-3p inhibits cell growth and metastasis in cervical cancer by targeting IGF2BP1

MicroRNAs (miRs) serve a role in promoting and suppressing tumors in various types of malignant cancer, such as cervical cancer. However, the regulatory mechanism of miR-124-3p in cervical cancer remains unclear. In the present study, miR-124-3p was significantly downregulated in cervical cancer tissues and cell lines compared with matching adjacent non-tumor tissues and the normal cervical epithelial cell line End1/E6E7, respectively. Decreased expression of miR-124-3p was associated with advanced cervical cancer and the results of an in vitro study demonstrated that the ectopic expression of miR-124-3p significantly decreased the proliferation, migration and invasion of cervical cancer Caski cells. Furthermore, insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) was identified as a novel target of miR-124-3p. Overexpression of miR-124-3p decreased the expression of IGF2BP1, whereas miR-124-3p knockdown promoted IGF2BP1 expression at the post-transcriptional level in Caski cells. Additionally, overexpression of IGF2BP1 attenuated the suppressive effects of miR-124-3p on the proliferation, migration and invasion of Caski cells. IGF2BP1 was upregulated in cervical cancer tissues and cell lines compared with matching adjacent non-tumor tissues and the End1/E6E7 cell line, respectively. Therefore, the present study suggests that miR-124-3p suppresses the growth and metastasis of cervical cancer by directly targeting IGF2BP. Thus, miR-124-3p may be developed as a novel method of treating cervical cancer.

Astrocyte elevated gene-1 promotes tumour growth and invasion by inducing EMT in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a common human malignancy with a high incidence rate and poor prognosis. Although astrocyte elevated gene 1 (AEG-1) expression is up-regulated in various human cancers and plays an important role in carcinogenesis and tumour progression, the impact of AEG-1 on the development and progression of OSCC remains unclear. Accordingly, this study aims to clarify the biological significance of AEG-1 in OSCC. We found AEG-1 to be overexpressed in OSCC tissues compared to normal oral mucosa. Knockdown or overexpression of AEG-1 in OSCC cell lines showed that AEG-1 is important for tumour growth, apoptosis, drug tolerance, and maintaining epithelial-mesenchymal transition (EMT)-mediated cell migration and invasion in vitro. Moreover, in a xenograft-mouse model generated by AEG-1-overexpressing SCC15 cells, we found that higher expression of AEG-1 promoted tumour growth, angiogenesis, and EMT in vivo. These findings provide mechanistic insight into the role of AEG-1 in regulating OSCC tumour growth, apoptosis, drug tolerance, and invasion, as well as AEG-1-induced activation of p38 and NF-κB signalling, suggesting that AEG-1 is an important prognostic factor and therapeutic target for OSCC.

MicroRNAs in gynecological cancers: Small molecules with big implications

Gynecological cancers (GCs) are often diagnosed at advanced stages, limiting the efficacy of available therapeutic options. Thus, there remains an urgent and unmet need for innovative research for the efficient clinical management of GC patients. Research over past several years has revealed the enormous promise of miRNAs. These small non-coding RNAs can aid in the diagnosis, prognosis and therapy of all major GCs, viz., ovarian cancers, cervical cancers and endometrial cancers. Mechanistic details of the miRNAs-mediated regulation of multiple biological functions are under constant investigation, and a number of miRNAs are now believed to influence growth, proliferation, invasion, metastasis, chemoresistance and the relapse of different GCs. Modulation of tumor microenvironment by miRNAs can possibly explain some of their reported biological effects. miRNA signatures have been proposed as biomarkers for the early detection of GCs, even the various subtypes of individual GCs. miRNA signatures are also being pursued as predictors of response to therapies. This review catalogs the knowledge gained from collective studies, so as to assess the progress made so far. It is time to ponder over the knowledge gained, so that more meaningful pre-clinical and translational studies can be designed to better realize the potential that miRNAs have to offer.

miR-124 inhibits proliferation, migration and invasion of malignant melanoma cells via targeting versican

MicroRNA (miR)-124 has been implicated in malignant melanoma (MM). However, the detailed regulatory mechanism of miR-124 in the malignant phenotypes of MM cells has remained largely elusive. A total of 68 pairs of MM tissues and adjacent tissues were collected. Reverse-transcription quantitative polymerase chain reaction was used to examine the mRNA expression of versican as well as the expression of miR-124, and the protein expression of versican was assessed by western blot analysis. MTT, wound healing and Transwell assays were used to determine cell proliferation, migration and invasion, respectively. A bioinformatics analysis and a luciferase reporter assay were used to confirm the targeting association between miR-124 and versican. miR-124 was significantly downregulated in MM tissues compared with that in adjacent non-tumorous tissues, and decreased expression of miR-124 was associated with increased tumor thickness, advanced clinical stage and node metastasis of MM. Furthermore, the expression levels of miR-124 were also reduced in MM cell lines compared with normal human skin HACAT cells. Forced overexpression of miR-124 caused a significant reduction in the proliferation, migration and invasion of MM A375 cells. Versican was significantly upregulated in MM tissues and cell lines, and was identified as a novel target of miR-124 in A375 cells using a luciferase reporter gene assay, and miR-124 was revealed to negatively regulate the protein expression of versican in A375 cells. Overexpression of versican impaired the suppressive effects of miR-124 on the proliferation, migration and invasion of A375 cells. In conclusion, miR-124 inhibited the malignant phenotypes of MM cells at least partly via inhibition of versican. Therefore, the miR-124/versican axis may be used as a promising therapeutic target for inhibiting MM growth and metastasis.

The association between polymorphisms in microRNA genes and cervical cancer in a Chinese Han population

Several studies have confirmed the crucial roles of microRNAs (miRNAs) in cancer occurrence. In addition, single nucleotide polymorphisms (SNPs) in miRNA genes have been associated with various cancers. The aim of the present study was to investigate the association of SNPs in miRNA genes with cervical intraepithelial neoplasia (CIN) and cervical cancer in a Chinese Han population. We searched SNPs in nineteen miRNAs by sequencing healthy individuals (n=50). Then, a total of 400 patients with CIN, 609 patients with cervical cancer and 583 healthy individuals were recruited to genotype the SNPs using a Taqman assay. The results showed that only five of the nineteen miRNAs had SNPs (rs11134527 in pri-miR-218-2; rs74693964 in pri-miR-145; rs6062251 in pri-miR-133a2; rs531564 in pri-miR-124-1; and rs1834306 in pri-miR-100) in this Chinese Han population. The frequency of the rs11134527A allele was significantly higher in the control group than in CIN and cervical cancer groups (P=0.011 and 0.035, respectively). The frequency of the rs531564G allele was higher in the CIN and control groups than in the cervical cancer group (P=0.019 and 0.017, respectively). These results indicated that rs11134527 in pri-miR-218-2 and rs531564 in pri-miR-124-1 could be associated with CIN and cervical cancer in the Chinese Han population.

Targeting epithelial-mesenchymal plasticity in cancer: clinical and preclinical advances in therapy and monitoring

The concept of epithelial-mesenchymal plasticity (EMP), which describes the dynamic flux within the spectrum of phenotypic states that invasive carcinoma cells may reside, is being increasingly recognised for its role in cancer progression and therapy resistance. The myriad of events that are able to induce EMP, as well as the more recently characterised control loops, results in dynamic transitions of cancerous epithelial cells to more mesenchymal-like phenotypes through an epithelial-mesenchymal transition (EMT), as well as the reverse transition from mesenchymal phenotypes to an epithelial one. The significance of EMP, in its ability to drive local invasion, generate cancer stem cells and facilitate metastasis by the dissemination of circulating tumour cells (CTCs), highlights its importance as a targetable programme to combat cancer morbidity and mortality. The focus of this review is to consolidate the existing knowledge on the strategies currently in development to combat cancer progression via inhibition of specific facets of EMP. The prevalence of relapse due to therapy resistance and metastatic propensity that EMP endows should be considered when designing therapy regimes, and such therapies should synergise with existing chemotherapeutics to benefit efficacy. To further improve upon EMP-targeted therapies, it is imperative to devise monitoring strategies to assess the impact of such treatments on EMP-related phenomenon such as CTC burden, chemosensitivity/-resistance and micrometastasis in patients.

Oncogenic Role of MicroRNA-30b-5p in Glioblastoma Through Targeting Proline-Rich Transmembrane Protein 2

MicroRNAs (miRs) have been found to play promoting or suppressive roles in different human cancers. However, the exact regulatory mechanism of miR-30b in glioblastoma remains unknown. Here we have shown that the expression of miR-30b is significantly increased in glioblastoma tissues and cell lines. Moreover, a high expression of miR-30b is significantly associated with a shorter survival time for glioblastoma patients. Knockdown of miR-30b caused a significant reduction in the proliferation, migration, and invasion of U87 and A172 cells. Proline-rich transmembrane protein 2 (PRRT2) was further identified as a novel target gene of miR-30b, and its protein expression is negatively regulated by miR-30b in U87 and A172 cells. Furthermore, PRRT2 is significantly downregulated in glioblastoma tissues and cell lines, and we found an inverse correlation between miR-30b and PRRT2 expression in glioblastoma tissues. In addition, inhibition of PRRT2 reversed the suppressive effect of miR-30b downregulation on the malignant phenotypes of U87 and A172 cells. Accordingly, we demonstrated that miR-30b promotes glioblastoma cell proliferation, migration, and invasion via targeting PRRT2. Therefore, miR-30b may be used as a promising therapeutic target for glioblastoma.

Use of Mature miRNA Strand Selection in miRNAs Families in Cervical Cancer Development

Aberrant miRNA expression is well recognized as a cancer hallmark, nevertheless miRNA function and expression does not always correlate in patients tissues and cell lines studies. In addition to this issue, miRNA strand usage conduces to increased cell signaling pathways modulation diversifying cellular processes regulation. In cervical cancer, 20 miRNA families are involved in carcinogenesis induction and development to this moment. These families have 5p and 3p strands with different nucleotide (nt) chain sizes. In general, mature 5p strands are larger: two miRNAs of 24 nt, 24 miRNAs of 23 nt, 35 miRNAs of 22 nt and three miRNAs of 21 nt. On the other hand, the 3p strands lengths observed are: seven miRNAs of 23 nt, 50 miRNAs of 22 nt, six miRNAs of 21 nt and four miRNAs of 20 nt. Based on the analysis of the 20 miRNA families associated with cervical cancer, 67 3p strands and 65 5p strands are selected suggesting selectivity and specificity mechanisms regulating cell processes like proliferation, apoptosis, migration, invasion, metabolism and Warburg effect. The insight reviewed here could be used in the miRNA based therapy, diagnosis and prognosis approaches.

Role of miRNAs in human cancer metastasis: Implications for therapeutic intervention

Metastasis is the spread and growth of localized cancer to new locations in the body and is considered the main cause of cancer-related deaths. Metastatic cancer cells display distinct genomic and epigenomic profiles and almost universally an aggressive pathophysiology. A better understanding of the molecular mechanisms and regulation of metastasis, including how metastatic tumors grow and survive in the nascent niche and the interactions of the emergent metastatic cancer cells within the local microenvironment may provide tools to design strategies to restrict metastatic dissemination. Aberrant microRNAs (miRNA) expression has been reported in metastatic cancer cells. MicroRNAs are known to regulate divergent and/or convergent metastatic gene pathways including activation of reprogramming switches during metastasis. An in-depth understanding of role of miRNAs in the metastatic cascade may lead to the identification of novel targets for anti-metastatic therapeutics as well as potential candidate miRNAs for cancer treatment. This review primarily focuses on the role of miRNAs in the mechanisms of cancer metastasis as well as implications for metastatic cancer treatment.