MicroRNA-10b promotes nucleus pulposus cell proliferation through RhoC-Akt pathway by targeting HOXD10 in intervetebral disc degeneration

The Role of MicroRNAS in Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a common and genetically heterozygous inflammatory rheumatic disease characterized by new bone formation, ankylosis and inflammation of hip, sacroiliac joints and spine. Until now, there is no method for early diagnosis of AS and the effective treatment available for AS patients remain largely undefined.We searched articles indexed in PubMed (MEDLINE) database using Medical Subject Heading (MeSH) or Title/Abstract words ("microRNA" and "ankylosing spondylitis") from inception up to November 2015.Genetic polymorphisms of miRNAs and their targets might alter the risk of AS development whereas certain miRNAs exhibit correlation with inflammatory index.Let-7i and miR-124 were upregulated whereas miR-130a was downregulated in circulating immune cells of AS patients. These deregulated miRNAs could modulate key immune cell functions, such as cytokine response and T-cell survival.miRNA deregulation is key to AS pathogenesis. However, clinical utilization of miRNAs for management of AS patients requires further support from future translational studies.

Dysregulated miR-98 Contributes to Extracellular Matrix Degradation by Targeting IL-6/STAT3 Signaling Pathway in Human Intervertebral Disc Degeneration

Intervertebral disc degeneration (IDD) is associated with dysregulated expression of microRNAs (miRNAs). However, the precise molecular mechanisms underlying this disorder remain unclear. Therefore, we tested the hypothesis that miRNAs modulate IDD through effects on the IL-6/STAT3 signaling pathway, a potential regulator of IDD. The miRNA expression profile was determined in nucleus pulposus (NP) tissues from patients with IDD and controls, employing miRNA microarray and quantitative real-time PCR (RT-qPCR). Biological functions of differential expression miRNAs were further investigated using immunofluorescent staining. Luciferase reporter assays and Western blotting were performed to determine miRNA targets. We identified 41 miRNAs that were differentially expressed in patients compared with controls. Following RT-qPCR confirmation, miR-98 was significantly downregulated in degenerative NP tissues. Moreover, its level was inversely correlated with grade of disc degeneration. Through gain-of-function and loss-of-function studies, miR-98 was shown to significantly promote type II collagen expression in NP cells. Interleukin-6 (IL-6) was identified as a target of miR-98. Knockdown of IL-6 induced effects on NP cells similar to those induced by miR-98. In contrast, IL-6 treatment abrogated the effects induced by miR-98 upregulation. Moreover, miR-98 dramatically suppressed expression of STAT3 target gene, MMP2. IL-6 treatment antagonized this effect, whereas knockdown of IL-6 by IL-6 short hairpin RNA (shIL-6) induced inhibitory effects on the expression of p-STAT3 and its main target genes, similar to miR-98. The mRNA level of IL-6 was inversely correlated with that of miR-98 in degenerative NP tissues. These results suggest the downregulation of miR-98 could promote IDD through the IL-6/STAT3 signaling pathway. Our findings also highlight miR-98 as a novel hopeful therapeutic target for IDD.

Role of microRNAs in primary central nervous system lymphomas

Primary central nervous system lymphomas (PCNSL) are extranodal non-Hodgkin lymphomas arising exclusively inside the CNS, and account for about 3% of primary intracranial tumours. This tumour lacks systemic manifestations and prognosis of patients with PCNSL remains poor despite recent advancement of chemoradiotherapy. MicroRNAs are small non-coding RNAs that post-transcriptionally downregulate gene expression by binding to target mRNAs, inducing their degradation or translational repression. MicroRNAs play significant roles in almost all malignancy-related biological processes, including cell proliferation, differentiation, apoptosis and metabolism. Many deregulated miRNAs has been identified in PCNSL but their biological significance remains to be fully elucidated. In this review, we summarize current evidence regarding the pathogenic role of PCNSL-associated microRNAs and their potential applications for diagnosis and prognostication of this deadly disease.

Adolescent idiopathic scoliosis: evidence for intrinsic factors driving aetiology and progression

Adolescent idiopathic scoliosis (AIS) is now considered to be a multifactorial heterogeneous disease, with recent genomic studies supporting the role of intrinsic factors in contributing to the onset of disease pathology and curve progression. Understanding the key molecular signalling pathways by which these intrinsic factors mediate AIS pathology may facilitate the development of pharmacological therapeutics and the identification of predictive markers of progression. The heterogenic nature of AIS has implicated multiple tissue types in the disease pathophysiology, including spinal bone, intervertebral disc and paraspinal muscles. In this review, we highlight some of the mechanisms and intrinsic molecular regulators within these different tissue types and review the evidence for their involvement in AIS pathology.

miR-448 suppressed gastric cancer proliferation and invasion by regulating ADAM10

MicroRNAs (miRNAs) are a class of short, noncoding RNAs that act a crucial role in tumor development. Previous studies showed that miR-448 expression was deregulated in many tumors. However, the role of miR-448 in gastric cancer (GC) remains unknown. In our study, we demonstrated that miR-448 expression was downregulated in GC tissues compared with the corresponding nontumor tissues. We also showed that miR-448 expression was downregulated in GC cell lines. Ectopic expression of miR-448 suppressed GC cell proliferation, colony formation, and invasion. Moreover, we identified A Disintegrin And Metalloproteinases 10 (ADAM10) as a direct target gene of miR-448 in GC cell. ADAM10 expression was upregulated in GC tissues and cells. Furthermore, the expression level of miR-448 was negatively correlated with the expression level of ADAM10 in GC tissues. Moreover, ADAM10 overexpression rescued the effect of miR-448-mediated GC cell proliferation, colony formation, and invasion. These results demonstrated that miR-448 might play as a tumor suppressor miRNA partly through targeting ADAM10 expression.

FoxC2 Enhances BMP7-Mediated Anabolism in Nucleus Pulposus Cells of the Intervertebral Disc

Bone-morphogenetic protein-7 (BMP-7) is a growth factor that plays a major role in mediating anabolism and anti-catabolism of the intervertebral disc matrix and cell homeostasis. In osteoblasts, Forkhead box protein C2 (FoxC2) is a downstream target of BMPs and promotes cell proliferation and differentiation. However, the role FoxC2 may play in degenerative human intervertebral disc tissue and the relationship between FoxC2 and BMP-7 in nucleus pulposus (NP) cells remain to be elucidated. This study aims to investigate the presence and signaling mechanisms of FoxC2 in degenerative human intervertebral disc tissue and NP cells. Western blot and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses were used to measure FoxC2 expression in the NP tissue and cells. Transfections were carried out to measure the effect of FoxC2 on BMP-7-mediated extracellular matrix upregulation. Adenoviral knock-down of Smad1 was performed to investigate the mechanism of BMP-7-induced FoxC2 expression. In degenerative NP tissue, FoxC2 was markedly upregulated and positively correlated with increased disc degeneration. Induction of NP cell proliferation was confirmed by using cell counting kit-8 assay, immunocytochemistry and real-time qRT-PCR for Ki67. FoxC2 led to decreased noggin expression and increased Smad1/5/8 phosphorylation. During combined treatment with BMP-7, FoxC2 greatly potentiated anabolism through synergistic mechanisms on ECM formation. Combination therapy using BMP-7 and FoxC2 may be beneficial to the treatment of intervertebral disc degeneration.

MiR-184 Regulates Proliferation in Nucleus Pulposus Cells by Targeting GAS1

OBJECTIVE

The precise mechanism of nucleus pulposus proliferation in the degeneration of the intervertebral disk pathogenesis remains to be implicated. MicroRNAs (MiRNAs) are a class of 18-22 nucleotides, which are small, noncoding RNAs that inhibit protein translation by binding to the 3'-UTR of target gene. Recent studies have shown that miRNAs play a crucial role in various cell biologies such as cell proliferation, invasion, migration, and cell cycle. However, the role of miR-184 in nucleus pulposus proliferation is still unknown.

METHOD

qRT-PCR was performed to measure the expression of miR-184. CCK-8 assay, qRT-PCR, and Western blot were used to measure the functional role of miR-184 in nucleus pulposus (NP) cells. Western blot and Luciferase assays were done to find the miR-184 target gene.

RESULT

We demonstrated that expression of miR-184 was upregulated in degenerative NP tissues compared with that in the control NP tissues, and the expression of miR-184 was positively correlated with disk degeneration grade. We identified Growth Arrest Specific Gene 1 (GAS1) as a direct target gene of miR-184 in NP cells, and ectopic expression of miR-184 promoted NP cells proliferation. In addition, we found that GAS1 expression was downregulated in degenerative NP tissues compared with that in the control NP tissues and the GAS1 expression was inversely correlated with the grade of disk degeneration. Moreover, we demonstrated that miR-184 overexpression could induce AKT phosphorylation and ectopic expression of GAS1 decreased the miR-184 overexpressing NP cells proliferation.

CONCLUSION

These results demonstrated that miR-184 and the GAS1/Akt pathway may be a potential therapeutic target for intervertebral disc degeneration.

miR-488 acts as a tumor suppressor gene in gastric cancer

MicroRNAs (miRNAs) are small, non-coding RNAs that modulate development, cell proliferation, and apoptosis. The deregulated expression of microRNAs is found in carcinogenesis including gastric cancer (GC). In this study, we showed that the expression levels of miR-488 were downregulated in GC tissues compared to in non-tumor tissues. In addition, the expression of miR-488 was also lower in GC cell lines in contrast with the gastric epithelial cell line (GES). In addition, the expression level of miR-488 was negatively correlated with the TNM stage in GC patients, and lower miR-488 expression was found in tumors with advanced TNM stage. The ectopic expression of miR-488 suppressed the GC cell proliferation, cell cycle, colony information, and migration. PAX6 was identified as a direct target gene of miR-488 in HGC-27. Moreover, we found that the expression level of PAX6 was upregulated in the GC tissues compared with the non-tumor tissues. The PAX6 expression level was correlated with the cancer TNM stage, and higher PAX6 expression was found in tumors with advanced TNM stage. Furthermore, there was an inverse correlation between PAX6 and miR-488 expression levels in GC tissues. Therefore, these studies demonstrated that miR-488 might act as a tumor suppressor miRNA in the development of GC.

New insights into MicroRNAs involves in drug resistance in diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) accounts for nearly 40% of non-Hodgkin's lymphoma cases. The combined chemotherapy of rituximab, cyclophosphamide, Adriamycin, vincristine, and prednisone (R-CHOP) is considered as the standard therapy for DLBCL; however, nearly half of the patients become refractory to the R-CHOP regimen. Early identification of drug resistance and therapeutic failures are crucial for the identification of high-risk patients. MicroRNAs (miRNAs) are a group of small and non-coding RNAs negatively regulating gene expression through binding to their target mRNAs. Recent studies demonstrated that miRNAs are involved in chemotherapeutic drug resistance in tumor. In our review, we summarize the current evidence on the role of miRNAs in the prediction and modulation of cellular response to rituximab, cyclophosphamide, Adriamycin, vincristine, and prednisone in DLBCL.

The roles of microRNAs in Wilms' tumors

Wilms' tumor is the most common renal tumor in children in which diffusely anaplastic or unfavorable histology foreshadows poor prognosis. MicroRNAs are small, non-coding RNAs that negatively regulate gene expression at the posttranscriptional level. Accumulating evidence shows that microRNA dysregulation takes part in the pathogenesis of many renal diseases, such as chronic kidney diseases, polycystic kidney disease, renal fibrosis, and renal cancers. In Wilms' tumor, dysregulation of some key oncogenic or tumor-suppressing microRNAs, such as miR-17~92 cluster, miR-185, miR-204, and miR-483, has been documented. In this review, we will summarize current evidence on the role of dysregulated microRNAs in the development of Wilms' tumor.

MicroRNA-613 inhibited ovarian cancer cell proliferation and invasion by regulating KRAS

MicroRNAs (miRNAs) play several important roles in carcinogenesis, and the dysregulation of miRNAs is associated with cancer progression. Little is known about the role of miR-613 in ovarian cancer. In the present study, we demonstrate that miR-613 expression is downregulated in human ovarian cancer cell lines and tissues. Additionally, miR-613 overexpression suppressed ovarian cancer cell proliferation, colony formation, and invasion. Furthermore, KRAS was identified as a target of miR-613. Reintroducing KRAS rescued the inhibitory effects exerted by miR-613 on ovarian cancer cell proliferation and invasion. Taken together, our findings suggest that miR-613 functions as a candidate tumor suppressor miRNA in ovarian cancer by directly targeting KRAS. To the best of our knowledge, this is the first study to show that miR-613 affects the proliferation and invasion of ovarian cancer.

Serum microRNAs as potential noninvasive biomarkers for glioma

Gliomas are derived from astroglial precursors or astrocytes, accounting for 40 % central nervous system tumors. MicroRNAs (miRNAs) are a class of endogenous, small (19- to 23-nucleotides) non-coding RNAs involved in cancer progression. Recent studies show that circulating miRNAs are associated with the clinicopathological features and prognosis of gliomas. Serum miRNAs may serve as novel biomarkers for gliomas diagnosis. This review explores the possibilities of using serum miRNAs as prognostic, diagnostic markers, and therapeutic targets in gliomas.

miR-372 suppresses tumour proliferation and invasion by targeting IGF2BP1 in renal cell carcinoma

OBJECTIVES

MicroRNAs (miRNAs) are endogenous small non-coding RNAs that regulate proteins and mRNAs for degradation or translational suppression. Up to now, the role of miR-372 in renal cell carcinoma has remained unknown; in this study, we have aimed to reveal its functional importance in this tumour.

MATERIALS AND METHODS

qRT-PCR was performed to measure expression levels of miR-372 in renal cell carcinoma cell lines and tissues. CCK-8 and an invasion assay were performed to measure its functional role. Luciferase assays, qRT-PCR and western blotting were performed to discover miR-372's target gene.

RESULTS

We demonstrated that miRNA-372 was down-regulated in renal cell carcinoma cell lines and tissue specimens; its over-expression inhibited cell proliferation and invasion. Moreover, we showed that miRNA-372 repressed insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) expression by directly interacting with its putative binding site at the 3'-UTR. Furthermore, ectopic expression of IGF2BP1 significantly reversed suppression of cell proliferation and invasion caused by miR-372 over-expression.

CONCLUSIONS

Our data indicated that miR-372 seemed to function as a tumour suppressor in renal cell carcinoma progression by inhibiting the IGF2BP1 expression.

miR-873 induces lung adenocarcinoma cell proliferation and migration by targeting SRCIN1

microRNAs (miRNAs) are endogenously expressed, conserved and small noncoding RNA that regulate gene expression by the post-transcriptional level. In this study, we aim to examine the role of miR-873 in lung adenocarcinoma. We found that the expression of miR-873 was upregulated in four lung adenocarcinoma cell lines and tissues. In addition, the expression levels of SRCIN1 were inversely correlated with the expression levels of miR-873 in lung adenocarcinoma tissues. Furthermore, SRCIN1 was confirmed asthe direct target of miR-873 by luciferase reporter assay and Western blotting. Overexpression of miR-873 promoted the proliferation and migration of lung adenocarcinoma cells, while SRCIN1 upregulation inhibited their proliferation and migration. Restoration of SRCIN1 could significantly reverse the proliferation and migration promotion imposed by miR-873. In summary, this study reveals for the first time that miR-873 increase the lung adenocarcinoma cell proliferation and migration through directly inhibiting SRCIN1 expression.

TOX gene: a novel target for human cancer gene therapy

Thymocyte selection-associated high mobility group box factor (TOX) is a member of an evolutionarily conserved DNA-binding protein family and is expressed in several immune-relevant cell subsets. TOX encodes a nuclear protein of the high-mobility group box superfamily. It contains a DNA-binding domain, which allows it to regulate transcription by modifying local chromatin structure and modulating the formation of multi-protein complexes. Previous studies have shown that TOX play important roles in immune system. More recently, several studies have described TOX expression is frequently upregulated in diverse types of human tumors and the overregulation often associates with tumor progression. Moreover, TOXis involved in the control of cell apoptosis, growth, metastasis, DNA repair and so on. In this review, we provide an overview of current knowledge concerning the role of TOX in tumor development and progression biology function. To our knowledge, this is the first review about the role of thisnew oncogene in tumor development and progression.

miR-599 Inhibits Vascular Smooth Muscle Cells Proliferation and Migration by Targeting TGFB2

Aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) play a crucial role in the pathogenesis of cardiovascular diseases including coronary heart disease, restenosis and atherosclerosis. MicroRNAs are a class of small, non-coding and endogenous RNAs that play critical roles in VSMCs function. In this study, we showed that PDGF-bb, as a stimulant, promoted VSMCs proliferation and suppressed the expression of miR-599. Moreover, overexpression of miR-599 inhibited VSMCs proliferation and also suppressed the PCNA and ki-67 expression. In addition, we demonstrated that ectopic expression of miR-599 repressed the VSMCs migration. We also showed that miR-599 inhibited type I collagen, type V collagen and proteoglycan expression. Furthermore, we identified TGFb2 as a direct target gene of miR-599 in VSMCs. Overexpression of TGFb2 reversed miR-599-induced inhibition of VSMCs proliferation and type I collagen, type V collagen and proteoglycan expression. In conclusion, our findings suggest miR-599 plays a crucial role in controlling VSMCs proliferation and matrix gene expression by regulating TGFb2 expression.

The role of miRNAs in cutaneous squamous cell carcinoma

MicroRNAs (miRs) are small, noncoding RNAs that negatively regulate gene expressions at posttranscriptional level. Each miR can control hundreds of gene targets and play important roles in various biological and pathological processes such as hematopoiesis, organogenesis, cell apoptosis and proliferation. Aberrant miR expression contributes to initiation and cell progression of cancers. Accumulating studies have found that miRs play a significant role in cutaneous squamous cell carcinoma (cSCC). Deregulations of miRs may contribute to cSCC carcinogenesis is through acting as oncogenic or tumour suppressive miRs. In this study, we summarized the recent data available on cSCC‐associated miRs. In particular, we will discuss the contribution of miR to the initiation and progression of cSCCs. Although there are many obstacles to be overcome, clinical use of miRs as biomarkers for diagnosis, prediction of prognosis and target for therapies, will be a promising area in the future with more expression and functional role of miRs revealed.

MicroRNA expression and its implications for diagnosis and therapy of tongue squamous cell carcinoma

Tongue squamous cell carcinoma (TSCC) is the most common type of oral squamous cell carcinomas and is well known for its high rate of lymph nodal metastasis. Despite the identification of many molecular mechanisms in TSCC, the number of deaths associated with TSCC increased during the past 5 years. MicroRNAs (miRNAs) are a family of small non-coding RNA molecules, which regulate gene expression by either translational inhibition or mRNA degradation. miRNAs have been proven to be key regulators of various biological and pathological processes including cell proliferation, development and tumourigenesis. Increasing evidence has demonstrated that the deregulated miRNAs are implicated in the diagnosis and treatment of TSCC. In this review, we summarized the expressions and roles of miRNAs in TSCC and comment on the potential roles of miRNAs in diagnosis, prognosis and treatment of this malignancy.

Identification of the potential molecular targets for human intervertebral disc degeneration based on bioinformatic methods

The present study aimed to explore potential molecular targets and gain further insights into the mechanism of intervertebral disc degeneration (IDD) progression. Microarray datasets of GSE19943, GSE15227 and GSE34095 were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) in 3 IDD specimens compared with 3 controls in GSE34095, DEGs in 7 grade III and 3 grade IV samples compared with 5 grade II samples in GSE19943, and differentially expressed miRNAs in 3 degenerated samples compared with 3 controls in GSE15227 were screened. Grade III‑ and IV‑specific networks were constructed and grade‑specific genes were extracted. The network features were analyzed, followed by Gene Ontology (GO) enrichment analysis and pathway enrichment analysis of grade‑specific genes and DEGs identified in GSE34095. Furthermore, miRNA‑pathway interactions were analyzed using Fisher's exact test. Tumor protein p53 (TP53) was a hub gene in the grade III‑specific network and ubiquitin C (UBC) was identified to be a hub gene in the grade IV‑specific network. Six significant features were identified by grade‑specific network topology analysis. Grade‑specific genes and DEGs were involved in different GO terms and pathways. Differentially expressed miRNAs were identified to participate in 35 pathways, among which 6 pathways were significantly enriched by DEGs, including apoptosis. The present study identified that key genes (TP53 and UBC) and miR‑129‑5p may participate in the mechanism of IDD progression. Thus, they may be potential therapeutic targets for IDD.

microRNA deregulation in keloids: an opportunity for clinical intervention?

Keloids are defined as benign dermal scars invading adjacent healthy tissue, characterized by aberrant fibroblast dynamics and overproduction of extracellular matrix. However, the aetiology and molecular mechanism of keloid production remain poorly understood. Recent discoveries have shed new light on the involvement of a class of non-coding RNAs known as microRNAs (miRNA), in keloid formation. A number of miRNAs have differential expression in keloid tissues and keloid-derived fibroblasts. These miRNAs have been characterized as novel regulators of cellular processes pertinent to wound healing, including extracellular matrix deposition and fibroblast proliferation. Delineating the functional significance of miRNA deregulation may help us better understand pathogenesis of keloids, and promote development of miRNA-directed therapeutics against this condition.

MicroRNA-411 inhibited matrix metalloproteinase 13 expression in human chondrocytes

Osteoarthritis (OA) is the most common joint degenerative disease affecting the joint structure, leading to loss of joint function and tissue destruction. Recent studies have demonstrated that miRNAs are involved in many pathological conditions, including OA. The study was to investigate the role of miR-411 in the pathogenesis of OA. The expression of miR-411 was downregulated in OA cartilage compared with in normal cartilage. Conversely, the expression of MMP-13 was upregulated in OA cartilage compared with in normal cartilage. IL-1β treatment repressed miR-411 expression in chondrocytes. Moreover, we identified MMP-13 as a direct target gene of miR-411 in chondrocytes and overexpression of miR-411 inhibited the MMP-13 expression. Furthermore, overexpression of miR-411 increased the expression of type II collagen and type IV collagen expression in chondrocytes. MiR-411 is a crucial regulator of MMP-13 in chondrocytes and may response to the development of OA.

miR-506 inhibits the proliferation and invasion by targeting IGF2BP1 in glioblastoma

Increasing evidence has indicated that microRNAs (miRNAs) play an essential role in cancers. Deregulation of miR-506 was reported in several cancers. However, the expression and function of miR-506 in glioblastoma remain unclear. Our data showed that the level of miR-506 was downregulated in glioblastoma tissues and cell lines. Overexpression of miR-506 repressed cell growth, blocked G1/S transition, and suppressed cell invasion in glioblastoma cell. Moreover, IGF2BP1 was a direct target of miR-506 in glioblastoma cells. Knockdown of IGF2BP1 recapitulated the anti-proliferative and anti-invasive effects of miR-506, whereas IGF2BP1 overexpression antagonized the tumor-suppressive function of miR-506. Our data showed that miRNA-506 played a tumor suppressor gene role in human glioblastoma by regulating IGF2BP1 gene and might be a new therapeutic target of human glioblastoma.

MicroRNA-346 functions as an oncogene in cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is an epidermal keratinocyte-derived skin tumor, which is the second most common skin cancer in the general population. Recently, studies showed that microRNAs (miRNAs) played an important role in the development of cancer. In our study, we showed that the expression of SRCIN1 was lower in cSCC tissues than in the matched normal tissues. Moreover, there was significant inversed correlation between miR-346 and SRCIN1 in cSCC tissues. The luciferase reporter assay data showed that miR-346 can target the SRCIN1 message via the 3'-untranslated region (UTR) of SRCIN1. Overexpression of miR-346 inhibited the messenger RNA (mRNA) and protein expression of SRCIN1 in the A431 cells. In addition, ectopic expression of miR-346 promoted the A431 cell proliferation and migration. Meanwhile, SRCIN1 overexpression inhibited the A431 cell proliferation and migration. Rescue experiment has showed that SRCIN1 overexpression reduced the miR-346-induced A431 cell proliferation and migration. Herein, this study may provide miR-346 as a new therapeutic target for cSCC.

miR-203 Acts as a Tumor Suppressor Gene in Osteosarcoma by Regulating RAB22A

microRNAs (miRNAs), small noncoding RNAs of 19–25 nt, play an important roles in the pathological processes of tumorigenesis. The object of this study was to study the expression and function of miR-203 and to found its target gene in osteosarcoma. In our study, we found the expression level of miR-203 was significantly downregulated in osteosarcoma cell lines and tissues. In addition, overexpression of miR-203 inhibited the osteosarcoma cell proliferation and migration and inhibited Mesenchymal-to-Epithelial reversion Transition (MErT). Moreover, we identified RAB22A as a direct target of miR-203 and RAB22A overexpression blocks the roles of miR-203 in osteosarcoma cell. Furthermore, we demonstrated that RAB22A expression was upregulated in human osteosarcoma cell lines and tissues. Take together, our results demonstrated that miR-203 act as a tumor suppressor miRNA through regulating RAB22A expression and suggested its involvement in osteosarcoma progression and carcinogenesis.

Identification and profiling of microRNAs associated with white and black plumage pigmentation in the white and black feather bulbs of ducks by RNA sequencing

MicroRNAs (miRNAs) play important roles in many biological processes by regulating gene expression at the post-transcriptional level. However, the mechanism by which specific miRNAs may regulate plumage pigmentation has remained largely elusive. In this study, we sequenced miRNAs using Solexa sequencing and then performed a detailed analysis of their expression profiles between the black and white feather bulbs of ducks from Cui Hei, Kaiya, Liancheng pure breeds and a Kaiya-Liancheng F2 population. mirdeep2 software identified 121 conserved and eight novel miRNAs. Five differentially expressed miRNAs between the two tissues types were also identified by degseq software. Notably, miR-204 was predominantly expressed in black feather bulbs. To further validate the sequencing data, we applied stem-loop quantitative PCR of ten known miRNAs based on the identified sequences. Furthermore, in exploring the temporal expression pattern of miR-204, we performed profiling in nine duck tissues. The targets of these miRNAs were predicted using a PITA algorithm and were later grouped based on Gene Ontology and KEGG pathway analysis using the DAVID website. The melanogenesis pathway was among the identified signalling pathways, implying key roles of these miRNAs in plumage pigmentation. Expression analysis of the target genes in the melanogenesis pathways was also performed. This study provides the foundation for subsequent studies on the prospective practical role for such miRNAs in post-transcriptional gene regulation linked to plumage pigmentation.

MicroRNA-454 functions as an oncogene by regulating PTEN in uveal melanoma

MicroRNAs (miRNAs) regulate gene expression by targeted repression of transcription and translation, and are involved in carcinogenesis. In this study, we demonstrated that the expression of miR-454 was up-regulated in uveal melanoma tissues compared to normal tissues. Ectopic expression of miR-454 resulted in significant promotion of cell proliferation, colony formation, invasion and induction of cell cycle in uveal melanoma cells. Furthermore, we identified PTEN as a direct target of miR-454. Our data revealed that ectopic expression of PTEN restored the effects of miR-454 on cell proliferation and invasion in uveal melanoma cells. These findings support an oncogene role of miR-454 in development of uveal melanoma.

miR-211 promotes non-small cell lung cancer proliferation by targeting SRCIN1

MicroRNAs (miRNAs) are a class of small non-coding RNAs that, when dysregulated, are involved in the initiation and progression of various cancers, including lung cancer, in humans. In the current study, qRT-PCR was performed to measure miR-211 expression in human non-small cell lung cancer (NSCLC) cell lines and tissues. Cell proliferation, cell cycle, colony formation, and invasion were performed to detect the functional role of miR-211 in human NSCLC cell line. We used luciferase reporter assay to find the potential target of miR-211. We found that miR-211 expression was upregulated in human non-small cell lung cancer (NSCLC) cell lines and tissues. The overexpression of miR-211 enhanced NSCLC cell proliferation, colony formation, and invasion. SRC kinase signaling inhibitor 1 (SRCIN1) was identified as a direct target of miR-211. SRCIN1 silencing promoted cell proliferation, and SRCIN1 expression was downregulated in human NSCLC cell lines. Thus, miR-211 may function as an oncogenic miRNA in NSCLC, partly by regulating SRCIN1, and the modulation of miR-211 expression represents a potential strategy for the treatment of NSCLC patients.

PAQR3: a novel tumor suppressor gene

PAQR3, also known as RKTG (Raf kinase trapping to Golgi), is a member of the progestin and adipoQ receptor (PAQR) family. The role of PAQR3 as a tumor suppressor has recently been established in different types of human cancer in which PAQR3 exerts its biological function through negative regulation of the oncogenic Raf/MEK/ERK signaling. Multiple studies have found that PAQR3 downregulation frequently occurs in human cancers and is very often associated with tumor progression and shortened patients' survival. Moreover, restoring the expression of PAQR3 could induce apoptosis and inhibit proliferation and invasiveness of cancer cells. Downregulation of PAQR3 by oncogenic microRNAs has also been reported. In this review, we summarized current knowledge concerning the role of PAQR3 in tumor development. To our knowledge, this is the first review on the role of this novel tumor suppressor.

MicroRNA dysregulation in rhabdomyosarcoma: a new player enters the game

Rhabdomyosarcoma (RMS) is the most common of the soft tissue sarcomas with resultant high morbidity, frequently occuring in paediatric patients and young adults. While the molecular basis of RMS has received considerable attention, exact mechanisms underlying its development and metastasis remain unclear. MicroRNAs (miRNAs) are endogenously expressed small non-coding RNAs that negatively regulate gene expression via translational inhibition or mRNA degradation. Deregulated expression of miRNA has been implicated in initiation, progression, and metastasis of RMS. miRNAs have emerged as key regulators of several physiological and pathophysiological processes and have opened new avenues for diagnosis and treatment of RMS. This review summarizes deregulation and functional roles of miRNAs in RMS and their potential applications for diagnosis, prognosis and treatment of this malignancy. As a rapidly evolving field in basic and translational medicine, it is hopeful that miRNA research will ultimately improve management of RMS.

MicroRNA-410 promotes cell proliferation by targeting BRD7 in non-small cell lung cancer

miR-410 acts as an oncogene or tumor suppressor gene in some malignancies. However, its role in NSCLC is still unknown. In this study, we showed that the expression of miR-410 was up-regulated in both human NSCLC tissues and cells. Overexpression of miR-410 promoted cell proliferation, migration, and invasion of NSCLC. In addition, bromodomain-containing protein 7 (BRD7) was a direct target of miR-410. MiR-410-mediated downregulation of BRD7 led to increase Akt phosphorylation. Inhibition of Akt phosphorylation can rescue the effect of miR-410 on NSCLC cell. The expression of BRD7 was downregulated in NSCLC and was inversely expressed with miR-410 in NSCLC. Our data provided new knowledge regarding the role of miR-410 in the lung cancer progression.

The MicroRNA-217 Functions as a Potential Tumor Suppressor in Gastric Cancer by Targeting GPC5

Gastric cancer (GC) is one of the most common malignancies worldwide. Emerging evidence has shown that aberrant expression of microRNAs (miRNAs) plays important roles in cancer progression. However, little is known about the potential role of miR-217 in GC. In this study, we investigated the role of miR-217 on GC cell proliferation and invasion. The expression of miR-217 was down-regulated in GC cells and human GC tissues. Enforced expression of miR-217 inhibited GC cells proliferation and invasion. Moreover, Glypican-5 (GPC5), a new ocncogene, was identified as the potential target of miR-217. In addition, overexpression of miR-217 impaired GPC5-induced promotion of proliferation and invasion in GC cells. In conclusion, these findings revealed that miR-217 functioned as a tumor suppressor and inhibited the proliferation and invasion of GC cells by targeting GPC5, which might consequently serve as a therapeutic target for GC patients.

MicroRNA expression and its implications for diagnosis and therapy of gallbladder cancer

Gallbladder cancer is the most common biliary tract malignancy with poor prognosis. MicroRNAs (miRNAs) are a class of small, endogenous, non-coding RNAs of 19-23 nucleotides in length, which regulate gene expression at post-transcriptional and translational levels. Several studies have demonstrated aberrant expression of miRNAs in gallbladder cancer tissues. Recent evidences also demonstrated that specific miRNAs are functionally involved in gallbladder cancer development through modulating cell proliferation, apoptosis, migration, invasion and metastasis. In this review, we explore the possibilities of using miRNAs as prognostic, diagnostic markers and therapeutic targets in gallbladder cancer.

Up-Regulation of MiR-300 Promotes Proliferation and Invasion of Osteosarcoma by Targeting BRD7

Increasing reports suggest that deregulated microRNAs (miRNAs) might provide novel therapeutic targets for cancers. However, the expression and function of miR-300 in osteosarcoma is still unknown. In our study, we found that the expression of miR-300 was up-regulated in osteosarcoma tissues and cells compared with paired adjacent non-tumor bone tissues and osteoblastic cells using RT-qPCR. The enforced expression of miR-300 could promote cell proliferation, invasion and epithelial-mesenchymal transition (EMT). Moreover, we identified that bromodomain-containing protein 7 (BRD7), a new tumor suppressor gene, was a direct target of miR-300. Ectopic expression of BRD7 could significantly inhibit miR-300-promoted proliferation, invasion and EMT. Therefore, our results identify an important role for miR-300 in osteosarcoma through regulating BRD7 expression.

MicroRNA-494 inhibition protects nucleus pulposus cells from TNF-α-induced apoptosis by targeting JunD

BACKGROUND

Human nucleus pulposus cell (HNPC) apoptosis plays an important role in the development of intervertebral disc degeneration (IVDD). Our previous research revealed that among all of the dysregulated microRNAs in the degenerated nucleus pulposus tissues of patient with IVDD, miRNA-494 (miR-494) is the most significantly increased. However, the influence of miR-494 HNPC apoptosis has not been confirmed.

OBJECTIVE

This study was designed to evaluate the effect of miR-494 on the HNPC apoptosis induced by TNF-α and to explore the possible mechanism of this process.

METHODS

First, HNPCs were stimulated with TNF-α at different concentrations (0 ng/ml, 10 ng/ml, 50 ng/ml, or 100 ng/ml) for 0 h, 8 h, 16 h, or 24 h. Annexin V-PE/7-AAD assays and real-time quantitative PCR were used to detect the cell apoptosis rates and miR-494 expression. Second, we successfully knocked down endogenous miR-494 in HNPCs via lentiviral antigomiR-494 vector infection and then stimulated with TNF-α (100 ng/ml, 16 h). The rates of apoptosis and miR-494 expression were then detected again. Additionally, a dual-luciferase reporter assay and western blotting were used to determine whether JunD is a target of miR-494. Finally, western blotting was used to analyze the expression of cytochrome C.

RESULTS

We found that the rate of apoptosis increased with concentration, time (p < 0.05) and miR-494 expression (p < 0.05). The rate of apoptosis in the 100 ng/ml, 16 h group appeared to be suitable. After transfection, the apoptosis rate and miR-494 expression were significantly decreased in the antigomiR-494+TNF-α group compared to the controls (p < 0.05). We also revealed that JunD is a target of miR-494. Western blotting analysis demonstrated that treatment with the lentiviral antigomiR-494 vector resulted in increased expression of JunD (p < 0.05) and decreased expression of cytochrome C (p < 0.05).

CONCLUSION

These results indicated that miR-494 is a novel regulator of HNPC apoptosis induced by TNF-α. The knock-out of miR-494 expression protected the HNPCs from apoptosis via the up-regulation of JunD, which was possibly mediated via cytochrome C apoptotic signaling. These findings suggest that the miR-494/JunD signaling pathway might represent a novel therapeutic target for the prevention of IVDD.

MiR-506 suppresses tumor proliferation and invasion by targeting FOXQ1 in nasopharyngeal carcinoma

MiRNAs are small noncoding RNAs that play important roles in various biological processes including tumorigenesis. However, little is known about the expression and function of miR-506 in nasopharyngeal carcinoma (NPC). In this study, we showed that miR-506 was downregulated in nasopharyngeal carcinoma (NPC) cell lines and tissues. Ectopic expression of miR-506 dramatically suppressed cell proliferation, colony formation and invasion. Moreover, we identified the Forkhead box Q1 (FOXQ1) gene as a novel direct target of miR-506. MiR-506 exerts its tumor suppressor function through inhibition of the FOXQ1, which was involved in tumor metastasis and proliferation in various cancers. Furthermore, the expression of FOXQ1 is up-regulated in NPC cell lines and tissues. Taken together, our results indicate that miR-506 functions as a tumor suppressor miRNA in NPC and that its suppressive effects are mediated chiefly by repressing FOXQ1 expression.

MicroRNA-93 regulates collagen loss by targeting MMP3 in human nucleus pulposus cells

OBJECTIVES

Degenerated disc disease is one of the most common medical conditions in patients suffering from low back pain. Recent studies have shown that microRNAs can regulate cell function in many pathological conditions. The aim of this study was to investigate expression and role of miR-93 in disc degeneration.

MATERIALS AND METHODS

Quantitative RT-PCR was employed to investigate level of miR-93 in degenerative nucleus pulposus (NP) tissues. Then, functional analysis of miR-93 in regulating collagen II expression was performed. Subsequently, western blotting and luciferase reporter assay were used to detect the target gene.

RESULTS

We showed that miR-93 was significantly down-regulated in degenerative NP tissues and its levels were associated with grade of disc degeneration. Overexpression of miR-93 stimulated type II collagen expression in NP cells. Moreover, MMP3 was identified as a putative target of miR-93. MiR-93 inhibited MMP3 expression by directly targeting its 3'UTR, and this was abolished by miR-93 binding site mutations. Additionally, restoration of MMP3 in miR-93-overexpressed NP cells reversed effects of type II collagen expression. Expression of MMP3 inversely correlated with miR-93 expression in degenerative NP tissues.

CONCLUSIONS

Taken together, we demonstrated that miR-93 contributed to abnormal NP cell type II collagen expression by targeting MMP3, involved in intervertebral disc degeneration.

miR-709 up-regulated in hepatocellular carcinoma, promotes proliferation and invasion by targeting GPC5

OBJECTIVES

Hepatocellular carcinoma (HCC) is one of the most common cancers and is a significant leading cause of cancer-related deaths worldwide. Emerging evidence has shown that microRNAs (miRNAs) are associated with cancer development and progression. However, up to now little has been known concerning the role of miR-709 in HCC.

MATERIALS AND METHODS

Real-time RT-PCR was performed to detect expression of miR-709 in HCC cell lines and tissues. To further understand its role in HCC, we restored its expression in HepG2 cell line through transfection with miR-709 mimics or inhibitors. CCK-8 proliferation assay, migration assay and invasion assay were used to detect functional roles of miR-709. Luciferase assay and western blotting were performed to detect the target gene of miR-709.

RESULTS

We found that miR-709 was highly expressed in HCC tissues and in HCC cell lines by qRT-PCR. Re-expression of miR-709 in HCC cells remarkably promoted cell migration and invasiveness in vitro. Subsequent investigation revealed that glypican-5 (GPC5) was a direct and functional target of miR-709 in HCC cells where overexpression of miR-709 impaired GPC5-induced inhibition of proliferation and invasion. Finally, analysis of miR-709 and GPC5 levels in human HCC tissues revealed that miR-709 inversely correlated with GPC5 expression.

CONCLUSIONS

These results suggest that miR-709 may positively regulate invasion and metastasis of HCC through targeting GPC5.

MicroRNA-153 inhibits osteosarcoma cells proliferation and invasion by targeting TGF-β2

Increasing evidence indicates that microRNAs (miRNAs), a class of small noncoding RNAs, participate in almost every step of cellular processes. MiRNAs are aberrantly expressed in human cancers and contribute to cancer development and progression. Study of miRNAs may provide a new clue for understanding the mechanism of carcinogenesis and a new tool for cancer treatment. In the present study, miR-153 was downregulated in human osteosarcoma tissues and cell lines. Introduction of miR-153 mimics into the MG-63 cells inhibited cell proliferation and invasion. Our results further revealed that transforming growth factor beta 2 (TGF-β2) was negatively regulated by miR-153. Furthermore, overexpression of miR-153 decreased p-SMAD2, p-SMAD3, epidermal growth factor receptor (EGFR) and insulin-like growth factor binding protein-3 (IGFBP-3) expressions, which were the downstream signaling molecules of TGF-β. Furthermore, miRNA-153 suppressed TGF-β-mediated MG-63 proliferation and migration. Therefore, our results suggest that miR-153 may act as a tumor suppressor in osteosarcoma through targeting TGF-β2.

MicroRNA dysregulation in uveal melanoma: a new player enters the game

Uveal melanoma is the second most common form of melanoma and a predominant intraocular malignant tumor in adults. The development of uveal melanoma is a multistep process involving genetic and epigenetic alteration of proto-oncogenes and tumor-suppressor genes. Recent discoveries have shed a new light on the involvement of a class of noncoding RNA known as microRNAs (miRNAs) in uveal melanoma. A lot of miRNAs show differential expressions in uveal melanoma tissues and cell lines. Genes coding for these miRNAs have been characterized as novel oncogene and tumor-suppressor genes based on findings that these miRNAs control malignant phenotypes of uveal melanoma cells. Several studies have confirmed that dysregulation of miRNAs promotes cell-cycle progression, confers resistance to apoptosis, and enhances invasiveness and metastasis. Moreover, several miRNAs have also been shown to correlate with uveal melanoma initiation and progression, and thus may be used as biomarkers for early diagnosis and prognosis. Elucidating the biological aspects of miRNA dysregulation may help us better understand the pathogenesis of uveal melanoma and promote the development of miRNA directed-therapeutics against this disease.

MicroRNA in intervertebral disc degeneration

Aetiology of intervertebral disc degeneration (IDD) is complex, with genetic, developmental, biochemical and biomechanical factors contributing to the disease process. It is becoming obvious that epigenetic processes influence evolution of IDD as strongly as the genetic background. Deregulated phenotypes of nucleus pulposus cells, including differentiation, migration, proliferation and apoptosis, are involved in all stages of progression of human IDD. Non-coding RNAs, including microRNAs, have recently been recognized as important regulators of gene expression. Research into roles of microRNAs in IDD has been very active over the past 5 years. Our review summarizes current research enlightenment towards understanding roles of microRNAs in regulating nucleus pulposus cell functions in IDD. These exciting findings support the notion that specific modulation of microRNAs may represent an attractive approach for management of IDD.

MiRNAs in primary cutaneous lymphomas

Primary cutaneous lymphomas (PCL) compose a heterogeneous disease with still unknown aetiology and mechanisms of development. MicroRNAs (miRNAs) have recently been discovered as one of the crucial players in PCL carcinogenesis through post-transcriptional regulation of gene expression. miRNAs have been reported to be frequently deregulated in PCLs and their biological significance has been further confirmed in multiple functional experiments. Such studies help us understand molecular pathogenesis of PCL. In this review, we summarize expression of miRNAs and their corresponding roles in different subtypes of PCL. With expression and functional role of miRNAs revealed, investigation of their possible clinical use as biomarkers for diagnosis, prediction of prognosis and target for therapies, will be a promising area in the future.

Inhibition of microRNA-25 by tumor necrosis factor α is critical in the modulation of vascular smooth muscle cell proliferation

Atherosclerosis and coronary heart disease are characterized by a hyperplastic neointima and inflammation involving cytokines, such as tumor necrosis factor‑α (TNF‑α). TNF‑α is pleiotropic and mediates inflammation and proliferation in various cell types, such as vascular smooth muscle cells (VSMCs). The molecular mechanism for the pleiotropic effects of TNF‑α has not previously been fully elucidated. The current study identified that the expression of microRNA‑25 (miR‑25), a small noncoding RNA, was reduced in response to TNF‑α signaling in VSMCs. Restored miR‑25 expression inhibited cell proliferation and Ki‑67 expression. The present study indicated that cyclin‑dependent kinase 6 (CDK6) was the direct target gene of miR‑25 using mRNA and protein expression analysis, and luciferase assays. It was also observed that restored CDK6 expression in the miR‑25 mimic‑treated VSMCs partly reduced miR‑25‑mediated VSMC proliferation. In conclusion, miR‑25 is suggested to be important in TNF‑α‑induced abnormal proliferation of VSMCs.

Increased expression of microRNA-150 is associated with poor prognosis in non-small cell lung cancer

OBJECTIVES

The aim was to evaluate the clinical significance and prognostic value of tissue miR-150 expression in non-small cell lung cancer (NSCLC) patients.

MATERIALS AND METHODS

Quantitative real-time PCR was used to analyze the expression of miR-150. Overall survival (OS) was estimated using the Kaplan-Meier method, and the differences in survival were compared using the log-rank test. A Cox proportional hazards model was used for multivariate analysis.

RESULTS

Mean miR-150 levels were significantly higher in NSCLC tissues compared with matched non-cancerous tissues (4.07 ± 2.33 vs. 1.00 ± 0.46, P < 0.0001). The level of miR-150 in NSCLC was strongly correlated with lymph node metastasis (P = 0.04), distant metastasis (P = 0.01) and clinical TNM stage (P = 0.02). Kaplan-Meier analysis showed that the cumulative 5-year OS rate was 40.8% in the high expression group, and 69.2% in the low expression group. The log-rank test showed that the OS rate of patients with high miR-150 expression was significantly poorer than that of the remaining cases (P = 0.007).

CONCLUSION

Our data indicated that overexpression of miR-150 in NSCLC tissues has prognostic value.

MicroRNA expression and its clinical implications in Ewing's sarcoma

Ewing's sarcoma (EWS) is the second most common primary bone cancer, and is a predominant childhood malignant disease. Due to limited understanding of its pathogenesis and frequent occurrence of resistance to conventional types of treatment, its management remains difficult, and mortality is frequent. Development of EWS is a multistep process involving genetic and epigenetic alterations of protein-coding proto-oncogenes and tumour-suppressor genes. MicroRNAs (miRNAs) have recently been discovered as a new category of non-protein coding; small RNA molecules that regulate gene expression at the post-transcriptional level. Substantial numbers of deregulated miRNAs have been documented in EWS and their biological significance has been confirmed in multiple functional experiments. Several studies have confirmed involvement of miRNAs in various steps of EWS pathogenesis, from occurrence to metastasis. Functionally, miRNA dysregulation may promote cell-cycle progression, confer resistance to apoptosis, and enhance invasiveness and metastasis. These miRNAs have opened a novel field in cancer research with potential clinical utilization for screening, diagnosis, prognostics and prediction of response to treatment. Elucidating biological aspects of miRNA dysregulation may help better understand pathogenesis of EWS and promote development of miRNA directed-therapeutics against it.