• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2813-2818
• /
• 2012

Background: Considerable evidence suggests that metadherin (MTDH) is a potentially crucial mediator of tumor malignancy and an important therapeutic target for simultaneously enhancing chemotherapy efficacy and reducing metastasis risk. Inhibition of MTDH expression by RNA interference has been shown in several previous research, but silencing MTDH expression by microRNA (miRNA) interference in breast cancer has not been established. In the present study, we investigated the role of MTDH-miRNA in down-regulation of proliferation, motility and migration of breast carcinoma cells. Methods: Expression vectors of recombinant plasmids expressing artificial MTDH miRNA were constructed and transfected to knockdown MTDH expression in MDA-MB-231 breast cancer cells. Expression of MTDH mRNA and protein was detected by RT-PCR and Western blot, respectively. MTT assays were conducted to determine proliferation, and wound healing assays and transwell migration experiments for cell motility and migration. Results: Transfection of recombinant a plasmid of pcDNA-MTDH-miR-4 significantly suppressed the MTDH mRNA and protein levels more than 69% in MDA-MB-231 breast cancer cells. This knockdown significantly inhibited proliferation, motility and migration as compared with controls. Conclusions: MTDH-miRNA may play an important role in down-regulating proliferation, motility and migration in breast cancer cells, and should be considered as a potential small molecule inhibitor therapeutic targeting strategy for the future.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.10
• /
• pp.1371-1382
• /
• 2016

MicroRNAs (miRNAs) are short non-coding RNAs that post-transcriptionally regulate expression of mRNAs in many biological pathways. Liver plays an important role in the feed efficiency of animals and high and low efficient cattle demonstrated different gene expression profiles by microarray. Here we report comprehensive miRNAs profiles by next-gen deep sequencing in Angus cattle divergently selected for residual feed intake (RFI) and identify miRNAs related to feed efficiency in beef cattle. Two microRNA libraries were constructed from pooled RNA extracted from livers of low and high RFI cattle, and sequenced by Illumina genome analyser. In total, 23,628,103 high quality short sequence reads were obtained and more than half of these reads were matched to the bovine genome (UMD 3.1). We identified 305 known bovine miRNAs. Bta-miR-143, bta-miR-30, bta-miR-122, bta-miR-378, and bta-let-7 were the top five most abundant miRNAs families expressed in liver, representing more than 63% of expressed miRNAs. We also identified 52 homologous miRNAs and 10 novel putative bovine-specific miRNAs, based on precursor sequence and the secondary structure and utilizing the miRBase (v. 21). We compared the miRNAs profile between high and low RFI animals and ranked the most differentially expressed bovine known miRNAs. Bovine miR-143 was the most abundant miRNA in the bovine liver and comprised 20% of total expressed mapped miRNAs. The most highly expressed miRNA in liver of mice and humans, miR-122, was the third most abundant in our cattle liver samples. We also identified 10 putative novel bovine-specific miRNA candidates. Differentially expressed miRNAs between high and low RFI cattle were identified with 18 miRNAs being up-regulated and 7 other miRNAs down-regulated in low RFI cattle. Our study has identified comprehensive miRNAs expressed in bovine liver. Some of the expressed miRNAs are novel in cattle. The differentially expressed miRNAs between high and low RFI give some insights into liver miRNAs regulating physiological pathways underlying variation in this measure of feed efficiency in bovines.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.7
• /
• pp.3313-3317
• /
• 2012

Prostate cancer is a highly prevalent disease in older men of the western world. MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression via posttranscriptional inhibition of protein synthesis. To identify the diagnostic potential of miRNAs in prostate cancer, we downloaded the miRNA expression profile of prostate cancer from the GEO database and analysed the differentially expressed miRNAs (DE-miRNAs) in prostate cancerous tissue compared to non-cancerous tissue. Then, the targets of these DE-miRNAs were extracted from the database and mapped to the STRING and KEGG databases for network construction and pathway enrichment analysis. We identified a total of 16 miRNAs that showed a significant differential expression in cancer samples. A total of 9 target genes corresponding to 3 DE-miRNAs were obtained. After network and pathway enrichment analysis, we finally demonstrated that miR-20 appears to play an important role in the regulation of prostate cancer onset. MiR-20 as single biomarker or in combination could be useful in the diagnosis of prostate cancer. We anticipate our study could provide the groundwork for further experiments.

• Molecules and Cells
• /
• v.40 no.8
• /
• pp.587-597
• /
• 2017

MicroRNAs (miRNAs) are essential small RNA molecules that regulate the expression of target mRNAs in plants and animals. Here, we aimed to identify miRNAs and their putative targets in Hibiscus syriacus, the national flower of South Korea. We employed high-throughput sequencing of small RNAs obtained from four different tissues (i.e., leaf, root, flower, and ovary) and identified 33 conserved and 30 novel miRNA families, many of which showed differential tissuespecific expressions. In addition, we computationally predicted novel targets of miRNAs and validated some of them using 5' rapid amplification of cDNA ends analysis. One of the validated novel targets of miR477 was a terpene synthase, the primary gene involved in the formation of disease-resistant terpene metabolites such as sterols and phytoalexins. In addition, a predicted target of conserved miRNAs, miR396, is SHORT VEGETATIVE PHASE, which is involved in flower initiation and is duplicated in H. syriacus. Collectively, this study provides the first reliable draft of the H. syriacus miRNA transcriptome that should constitute a basis for understanding the biological roles of miRNAs in H. syriacus.

• BMB Reports
• /
• v.56 no.3
• /
• pp.190-195
• /
• 2023

We propose a novel blood biomarker detection method that uses miRNA super-resolution imaging to enable the early diagnosis of Alzheimer's disease (AD). Here, we report a single-molecule detection method for visualizing disease-specific miRNA in tissue from an AD mice model, and peripheral blood mononuclear cells (PBMCs) from AD patients. Using optimized Magnified Analysis of Proteome (MAPs), we confirmed that five miRNAs contribute to neurodegenerative disease in the brain hippocampi of 5XFAD and wild-type mice. We also assessed PBMCs isolated from the whole blood of AD patients and a healthy control group, and subsequently analyzed those samples using miRNA super-resolution imaging. We detected more miR-200a-3p expression in the cornu ammonis 1 and dentate gyrus regions of 3 month-old 5XFAD mice than in wild-type mice. Additionally, miRNA super-resolution imaging of blood provides AD diagnosis platform for studying miRNA regulation inside cells at the single molecule level. Our results present a potential liquid biopsy method that could improve the diagnosis of early stage AD and other diseases.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.20
• /
• pp.8595-8601
• /
• 2014

Background: miR-200a expression is frequently altered in numerous cancers. The aim of the present study was to determine the role of microRNA-200a in advanced ovarian carcinomas. Materials and Methods: We measured miR-200a expression in 72 matched normal ovarian tissues and advanced ovarian carcinomas, and also two ovarian carcinoma cell lines (SKOV3 and SKOV3.ip1 - the latter being more invasive and metastatic than the parental SKOV3) by stem-loop real-time RT-PCR based on TaqMan microRNA assay using U6 as a reference. Levels of miR-200a expression were compared by disease stage, tumor grade, histology, and lymph node involvement. To evaluate the role of microRNA-200a, cell proliferation and invasion of SKOV-3 and SKOV-3.ip1 were analyzed with miR-200a inhibitor/mimic transfected cells. Results: Of 72 paired samples, 65 cancer tissues overexpressed microRNA-200a greater than two fold in comparison with matched normal epithelium. Specifically, patients with lymph node metastasis showed significant elevation. The level correlated with clinicopathological features, including high tumor grade, late disease stage, most notably with lymph node metastasis, but not with tumor histology. In addition, SKOV-3.ip1 cells also overexpressed miR-200a compared with SKOV-3, and miR-200a inhibitor transfected SKOV-3.ip1 cells showed significant reduction in cellular proliferation and invasion, while a miR-200a mimic stimulated the opposite behavior. Conclusions: We provide definitive evidence that miR-200a is up-regulated in a significant proportion of advanced ovarian carcinomas, and that elevated miR-200a expression facilitates tumor progression. Our findings support the notion that miR-200a is an onco-microRNA for ovarian cancer, and elevation is a useful potential diagnostic indicator. This study also provides a solid basis for further functional analysis of miR-200a in advanced ovarian cancer.

• International Journal of Oral Biology
• /
• v.43 no.4
• /
• pp.223-230
• /
• 2018

Exosomes are Nano-sized lipid vesicles secreted from mammalian cells containing diverse cellular materials such as proteins, lipids, and nucleotides. Multiple lines of evidence indicate that in saliva, exosomes and their contents such as microRNAs (miRNAs) mediate numerous cellular responses upon delivery to recipient cells. The objective of this study was to characterize the different expression profile of exosomal miRNAs in saliva samples, periodically isolated from a single periodontitis patient. Unstimulated saliva was collected from a single patient over time periods for managing periodontitis. MicroRNAs extracted from each phase were investigated for the expression of exosomal miRNAs. Salivary exosomal miRNAs were analyzed using Affymetrix miRNA arrays and prediction of target genes and pathways for its different expression performed using DIANA-mirPath, a web-based, computational tool. Following the delivery of miRNA mimics (hsa-miR-4487, -4532, and -7108-5p) into human gingival fibroblasts, the expression of pro-inflammatory cytokines and activation of the MAPK pathway were evaluated through RT-PCR and western blotting. In each phase, 13 and 43 miRNAs were found to be differently expressed $({\mid}FC{\mid}{\geq}2)$. Among these, hsa-miR-4487 $({\mid}FC{\mid}=9.292005)$ and has-miR-4532 $({\mid}FC{\mid}=18.322697)$ were highly up-regulated in the clinically severe phase, whereas hsa-miR-7108-5p $({\mid}FC{\mid}=12.20601)$ was strongly up-regulated in the clinically mild phase. In addition, the overexpression of miRNA mimics in human gingival fibroblasts resulted in a significant induction of IL-6 mRNA expression and p38 phosphorylation. The findings of this study established alterations in salivary exosomal miRNAs which are dependent on the severity of periodontitis and may act as potential candidates for the treatment of oral inflammatory diseases.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.5
• /
• pp.1901-1906
• /
• 2012

Background: The discovery that microRNA (miRNA) regulates metastasis provide a principal molecular basis for tumor heterogeneity. A characteristic of solid tumors is their heterogenous distribution of blood vessels, with significant hypoxia occurring in regions (centers of tumor) of low blood flow. It is necessary to discover the mechanism of breast cancer metastasis in relation to the fact that there is a differential distribution of crucial microRNA in tumors from centers to edges. Methods: Breast tissues from 48 patients (32 patients with breast cancer) were classified into the high invasive and metastatic group (HIMG), low invasive and metastatic group (LIMG), and normal group. Samples were collected from both the centers and edges of all tumors. The first six specimens were detected by microRNA array, and the second ten specimens were detected by real-time qRT-PCR and Western blot analyses. Correlation analysis was performed between the miRNAs and target proteins. Results: The relative content of miR-20a and miR-20b was lower in the center of the tumor than at the edge in the LIMG, lower at the edge of the tumor than in the center in the HIMG, and lower in breast cancer tissues than in normal tissues. VEGF-A and HIF-1alpha mRNA levels were higher in the HIMG than in the LIMG, and levels were higher in both groups than in the normal group; there was no difference in mRNA levels between the edge and center of the tumor. VEGF-A and HIF-1alpha protein levels were higher in the HIMG than in the LIMG, and protein levels in both groups were higher than in the normal group; there was a significant difference in protein expression between the edge and center of the tumor. Correlation analysis showed that the key miRNAs (miR-20a and miR-20b) negatively correlated with the target proteins (VEGF-A and HIF-1alpha). Conclusions: Our data suggest that miR-20a and miR-20b are differentially distributed in breast cancer, while VEGF-A and HIF-1alpha mRNA had coincident distributions, and VEGF-A and HIF-1alpha proteins had uneven and opposing distributions to the miRNAs. It appears that one of the most important facets underlying metastatic heterogeneity is the differential distribution of miR-20a and miR-20b and their regulation of target proteins.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.3
• /
• pp.1075-1079
• /
• 2014

MicroRNA expression is a research focus in studies of tumors. This article concentrates attention on potential links between tumors caused by mouse mammary tumor virus (MMTV) and human breast cancer, in order to provide theoretical basis for using mouse model to search for miRNA effects mediated by Wnt/beta-catenin signaling in human breast cancer. By analyzing interactions between miRNAs and the Wnt/beta-catenin signaling pathway in breast cancer, we hope to casts light on more biological functions of miRNAs in the process of tumor formation and growth and to explore their potential value in cancer diagnosis, prognosis and treatment. Our endeavor aimed at providing theoretical basis for finding safer, more effective methods for treatment of human breast cancer at the miRNA molecular level.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.6
• /
• pp.3681-3684
• /
• 2013

Deregulated miRNAs participate in osteosarcoma genesis. In this study, the expression of miRNA-218 in human osteosarcomas, adjacent normal tissues and Saos-2 human osteosarcoma cells was first assessed. Then the precise role of miRNA-218 in osteosarcoma cells was investigated. Upon transfection with a miR-218 expression vector, the proliferation of Saos-2 human osteosarcoma cells determined using the ATPlite assay was significantly suppressed, whilw migration of Saos-2 cells detected by wound healing and invasion determined using transwells were dramatically inhibited. Potential target genes of miR-218 were predicted and T-cell lymphoma invasion and metastasis 1 (TIAM1) and matrix metalloproteinase 2 (MMP2) and 9 (MMP9) were identified. This was confirmed by western blotting, which showed that miR-218 expression inhibited TIAM1, MMP2 and MMP9 protein expression. Collectively, these data suggest that miR-218 acts as a tumor suppressor in osteosarcomas by down-regulating TIAM1, MMP2 and MMP9 expression.