• The Korean Journal of Physiology and Pharmacology
• /
• v.23 no.3
• /
• pp.171-179
• /
• 2019

Pituitary tumors are usually benign but can occasionally exhibit hormonal and proliferative behaviors. Dysregulation of the G1/S restriction point largely contributes to the over-proliferation of pituitary tumor cells. F-box protein S-phase kinase-interacting protein-2 (SKP2) reportedly targets and inhibits the expression of $p27^{Kip1}$, a well-known negative regulator of G1 cell cycle progression. In this study, SKP2 expression was found to be upregulated while $p27^{Kip1}$ expression was determined to be downregulated in rat and human pituitary tumor cells. Furthermore, SKP2 knockdown induced upregulation of $p27^{Kip1}$ and cell growth inhibition in rat and human pituitary tumor cells, while SKP2overexpression elicited opposite effects on $p27^{Kip1}$ expression and cell growth. The expression of microRNA-186 (miR-186) was reported to be reduced in pituitary tumors. Online tools predicted SKP2 to be a direct downstream target of miR-186, which was further confirmed by luciferase reporter gene assays. Moreover, miR-186 could modulate the cell proliferation and $p27^{Kip1}$-mediated cell cycle alternation of rat and human pituitary tumor cells through SKP2. As further confirmation of these findings, miR-186 and $p27^{Kip1}$ expression were downregulated, while SKP2 expression was upregulated in human pituitary tumor tissue samples; thus, SKP2 expression negatively correlated with miR-186 and $p27^{Kip1}$ expression. In contrast, miR-186 expression positively associated with $p27^{Kip1}$ expression. Taken together, we discovered a novel mechanism by which miR-186/SKP2 axis modulates pituitary tumor cell proliferation through $p27^{Kip1}$-mediated cell cycle alternation.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.23
• /
• pp.10107-10114
• /
• 2015

MicroRNA-27a is highly expressed in cancers and has been identified as an oncogenic microRNA. A genetic variant in pre-miR-27a (rs895819) with a transition of A to G has been demonstrated to be associated with cancer risk; however, the results of these studies remain conflicting rather than conclusive. Therefore, we performed a meta-analysis to derive a more precise estimation. Through searching PubMed or other databases up to March 2014 using the following MeSH terms and keywords, "miR-27a", "polymorphism" and "cancer", seventeen case-control studies were identified in this meta-analysis, including 7,813 cases and 9,602. Crude odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to investigate the association strength between rs895819 and the susceptibility of cancer. The results of the overall meta-analysis did not suggest any association between rs895819 polymorphism and cancer susceptibility, and this remained in Asians as a subgroup. In Caucasians, however, the rs895819 was associated with a reduced cancer risk in heterozygous (OR, 0.83; 95%CI, 0.75-0.93) and dominant models (OR, 0.84; 95%CI, 0.76-0.93), and the [G] allele of rs895819 showed a protective effect (OR, 0.90, 95%CI, 0.84-0.97). Further studies showed a significant association between the [G] allele of rs895819 and decreased risk of breast cancer (0.91; 95%CI, 0.85-0.98), and stratified analyses indicated a protective effect of the [G] allele in Caucasians (OR, 0.89; 95%CI, 0.82-0.98), younger breast cancer cases (OR, 0.87; 95%CI, 0.79-0.96), and in the group of unilateral breast cancer patients (OR, 0.90; 95%CI, 0.83-0.97). These findings suggest an association between pre-miR-27a polymorphism rs895819 and cancer risk in Caucasians. The protective effect of rs895819 [G] allele in younger breast cancer and in the group of unilateral breast cancer patients await further confirmation since the included studies in this meta-analysis were limited.

• Biomedical Science Letters
• /
• v.19 no.4
• /
• pp.348-352
• /
• 2013

microRNAs (miRNAs) play pivotal roles in controlling cell proliferation and differentiation. miRNA expression in human is becoming recognized as a new molecular mechanism of carcinogenesis. microRNA-34a (miR-34a), a member of the p53 network, was found to be regulated in multiple types of tumor. The purpose of this study was to define roles of miR-34a expression in cervical intraepithelial neoplasia with human papillomavirus infection, and its relationship with p53 protein expression. This study was performed to analyze expression of miR-34a by using qRT-PCR, and to evaluate p53 protein expression by using immunohistochemistry in 40 cases. Down-regulation of miR-34a expression was detected in 27 (67.5%) out of 40 cases and Immunoreactivity for p53 was found in 17 (42.5%) out of 40 cases. Nineteen (82.6%) of the 23 cases with a negative p53 expression showed a down-regulation miR-34a expression, there was a significant associations between miR-34a and p53 protein expression (P=0.04). These results suggest that miRNA-34a expression tend to be reduced depending on the advanced histologic grade, and down-regulation of miR-34a expression might be associated with inactivation of p53 protein expression by human papillomavirus infection.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.4
• /
• pp.1675-1679
• /
• 2014

Objectives: MicroRNAs (miRNAs) are important regulators of many physiological and pathological processes, including tumorigenesis and metastasis. In this study, we sought to determine the underlying molecular mechanisms of metastatic cervical carcinoma by performing miRNA profiling. Methods: Tissue samples were collected from ten cervical squamous cancer patients who underwent hysterectomy and pelvic lymph node (PLN) dissection in our hospital, including four PLN-positive (metastatic) cases and six PLN-negative (non-metastatic) cases. A miRNA microarray platform with 1223 probes was used to determine the miRNA expression profiles of these two tissue types and case groups. MiRNAs having at least 4-fold differential expression between PLN-positive and PLN-negative cervical cancer tissues were bioinformatically analyzed for target gene prediction. MiRNAs with tumor-associated target genes were validated by quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results: Thirty-nine miRNAs were differentially expressed (>4-fold) between the PLN-positive and PLN-negative groups, of which, 22 were up-regulated and 17 were down-regulated. Sixty-nine percent of the miRNAs (27/39) had tumor-associated target genes, and the expression levels of six of those (miR-126, miR-96, miR-144, miR-657, miR-490-5p, and miR-323-3p) were confirmed by quantitative (q)RT-PCR. Conclusions: Six MiRNAs with predicted tumor-associated target genes encoding proteins that are known to be involved in cell adhesion, cytoskeletal remodeling, cell proliferation, cell migration, and apoptosis were identified. These findings suggest that a panel of miRNAs may regulate multiple and various steps of the metastasis cascade by targeting metastasis-associated genes. Since these six miRNAs are predicted to target tumor-associated genes, it is likely that they contribute to the metastatic potential of cervical cancer and may aid in prognosis or molecular therapy.

• The Korean Journal of Physiology and Pharmacology
• /
• v.27 no.2
• /
• pp.131-141
• /
• 2023

Compelling evidence has demonstrated the critical role of circular RNAs (circRNAs) during lung adenocarcinoma (LUAD) progression. Herein, we explored a novel circRNA, circ_0129047, and detailed its mechanism of action. The expression of circ 0129047, microRNA-665 (miR-665), and protein tyrosine phosphatase receptor type B (PTPRB) in LUAD tissues and cells was determined using reverse transcription quantitative polymerase chain reaction and Western blotting. Cell Counting Kit8 and colony formation assays were conducted to detect LUAD cell proliferation, and western blotting was performed to quantify apoptosis-related proteins (Bcl2 and Bax). Luciferase reporter and RNA immunoprecipitation assays were used to validate the predicted interaction between miR-665 and circ_0129047 or PTPRB. A xenograft assay was used for the in vivo experiments. Circ_0129047 and PTPRB were downregulated in LUAD tissues and cells, whereas miR-665 expression was upregulated. Overexpression of circ_0129047 suppresses LUAD growth in vivo and in vitro. Circ_0129047 is the target of miR-665, and the miR-665 mimic ablated the antiproliferative and pro-apoptotic phenotypes of LUAD cells by circ_0129047 augmentation. MiR-665 targets the 3'UTR of PTPRB and downregulates PTPRB expression. PTPRB overexpression offsets the pro-proliferative potential of miR-665 in LUAD cells. Circ_0129047 sequestered miR-665 and upregulated PTPRB expression, thereby reducing LUAD progression, suggesting a promising approach for preventing LUAD.

• Journal of Korean Neurosurgical Society
• /
• v.65 no.5
• /
• pp.697-709
• /
• 2022

Objective : The present study aimed to identify the function of ischemic stroke (IS) patients' peripheral blood and its role in IS, explore the pathogenesis, and provide direction for clinical research progress by comprehensive bioinformatics analysis. Methods : Two datasets, including GSE58294 and GSE22255, were downloaded from Gene Expression Omnibus database. GEO2R was utilized to obtain differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs were performed using the database annotation, visualization and integrated discovery database. The protein-protein interaction (PPI) network of DEGs was constructed by search tool of searching interactive gene and visualized by Cytoscape software, and then the Hub gene was identified by degree analysis. The microRNA (miRNA) and miRNA target genes closely related to the onset of stroke were obtained through the miRNA gene regulatory network. Results : In total, 36 DEGs, containing 27 up-regulated and nine down-regulated DEGs, were identified. GO functional analysis showed that these DEGs were involved in regulation of apoptotic process, cytoplasm, protein binding and other biological processes. KEGG enrichment analysis showed that these DEGs mediated signaling pathways, including human T-cell lymphotropic virus (HTLV)-I infection and microRNAs in cancer. The results of PPI network and cytohubba showed that there was a relationship between DEGs, and five hub genes related to stroke were obtained : SOCS3, KRAS, PTGS2, EGR1, and DUSP1. Combined with the visualization of DEG-miRNAs, hsa-mir-16-5p, hsa-mir-181a-5p and hsa-mir-124-3p were predicted to be the key miRNAs in stroke, and three miRNAs were related to hub gene. Conclusion : Thirty-six DEGs, five Hub genes, and three miRNA were obtained from bioinformatics analysis of IS microarray data, which might provide potential targets for diagnosis and treatment of IS.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.11
• /
• pp.1824-1836
• /
• 2020

Objective: On the hypothesis that grazing of cattle prompts organs to secrete or internalize circulating microRNAs (c-miRNAs) in parallel with changes in energy metabolism, we aimed to clarify biological events in adipose, skeletal muscle, and liver tissues in grazing Japanese Shorthorn (JSH) steers by a transcriptomic approach. Methods: The subcutaneous fat (SCF), biceps femoris muscle (BFM), and liver in JSH steers after three months of grazing or housing were analyzed using microarray and quantitative polymerase chain reaction (qPCR), followed by gene ontology (GO) and functional annotation analyses. Results: The results of transcriptomics indicated that SCF was highly responsive to grazing compared to BFM and liver tissues. The 'Exosome', 'Carbohydrate metabolism' and 'Lipid metabolism' were extracted as the relevant GO terms in SCF and BFM, and/or liver from the >1.5-fold-altered mRNAs in grazing steers. The qPCR analyses showed a trend of upregulated gene expression related to exosome secretion and internalization (charged multivesicular body protein 4A, vacuolar protein sorting-associated protein 4B, vesicle associated membrane protein 7, caveolin 1) in the BFM and SCF, as well as upregulation of lipolysis-associated mRNAs (carnitine palmitoyltransferase 1A, hormone-sensitive lipase, perilipin 1, adipose triglyceride lipase, fatty acid binding protein 4) and most of the microRNAs (miRNAs) in SCF. Moreover, gene expression related to fatty acid uptake and inter-organ signaling (solute carrier family 27 member 4 and angiopoietin-like 4) was upregulated in BFM, suggesting activation of SCF-BFM organ crosstalk for energy metabolism. Meanwhile, expression of plasma exosomal miR-16a, miR-19b, miR-21-5p, and miR-142-5p was reduced. According to bioinformatic analyses, the c-miRNA target genes are associated with the terms 'Endosome', 'Caveola', 'Endocytosis', 'Carbohydrate metabolism', and with pathways related to environmental information processing and the endocrine system. Conclusion: Exosome and fatty acid metabolism-related gene expression was altered in SCF of grazing cattle, which could be regulated by miRNA such as miR-142-5p. These changes occurred coordinately in both the SCF and BFM, suggesting involvement of exosome in the SCF-BFM organ crosstalk to modulate energy metabolism.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.12
• /
• pp.1695-1704
• /
• 2014

Maternal malnutrition during pregnancy may give rise to female offspring with disrupted ovary functions in adult age. Neonatal ovary development predisposes adult ovary function, yet the effect of maternal nutrition on the neonatal ovary has not been described. Therefore, here we show the impact of maternal protein restriction on the expression of folliculogenic and steroidogenic genes, their regulatory microRNAs and promoter DNA methylation in the ovary of neonatal piglets. Sows were fed either standard-protein (SP, 15% crude protein) or low-protein (LP, 7.5% crude protein) diets throughout gestation. Female piglets born to LP sows showed significantly decreased ovary weight relative to body weight (p<0.05) at birth, which was accompanied with an increased serum estradiol level (p<0.05). The LP piglets demonstrated higher ratio of bcl-2 associated X protein/B cell lymphoma/leukemia-2 mRNA (p<0.01), which was associated with up-regulated mRNA expression of bone morphogenic protein 4 (BMP4) (p<0.05) and proliferating cell nuclear antigen (PCNA) (p<0.05). The steroidogenic gene, cytochrome P450 aromatase (CYP19A1) was significantly down-regulated (p<0.05) in LP piglets. The alterations in ovarian gene expression were associated with a significant down-regulation of follicle-stimulating hormone receptor mRNA expression (p<0.05) in LP piglets. Moreover, three microRNAs, including miR-423-5p targeting both CYP19A1 and PCNA, miR-378 targeting CYP19A1 and miR-210 targeting BMP4, were significantly down-regulated (p<0.05) in the ovary of LP piglets. These results suggest that microRNAs are involved in mediating the effect of maternal protein restriction on ovarian function through regulating the expression of folliculogenic and steroidogenic genes in newborn piglets.

• Journal of Life Science
• /
• v.27 no.2
• /
• pp.149-154
• /
• 2017

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-hodgkin lymphoma. Advances in the chemotherapeutic treatment of this disease have improved the outcomes of DLBCL; nonetheless, many patients still die of DLBCL, and therefore, a better understanding of this disease and identification of novel therapeutic targets are urgently required. In a recent gene expression profiling study, PDE (phosphodiesterase) 4B was found to be overexpressed in chemotherapy-resistant tumors. The major function of PDE4B is to inactivate the second messenger cyclic 3',5' monophosphate (cAMP) by catalyzing the hydrolysis of cAMP to 5'AMP. It is known that cAMP induces cell cycle arrest and/or apoptosis in B cells, and PDE4B abolishes cAMP's effect on B cells. However, the mechanism by which PDE4B is overexpressed remains unclear. Here, we show that the aberrant expression of miRNA may be associated with the overexpression of this gene. The PDE4B 3' untranslated region (UTR) has three functional binding sites of miR-23b, as confirmed by luciferase reporter assays. Interestingly, miR-23b-binding sites were evolutionarily conserved from humans to lizards, implying the critical role of PDE4B-miR-23b interaction in cellular physiology. The ectopic expression of miR-2 3b repressed PDE4B mRNA levels and enhanced intracellular cAMP concentrations. Additionally, miR-23b expression inhibited cell proliferation and survival of DLBCL cells only in the presence of forskolin, an activator of adenylyl cyclase, suggesting that miR-23b's effect is via the downregulation of PDE4B. These results together suggest that miR-23b could be a therapeutic target for overcoming drug resistance by repressing PDE4B in DLBCL.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.9
• /
• pp.1566-1575
• /
• 2017

MicroRNAs (miRNAs) are abundant in bovine milk and milk derived from other livestock, and they have functional roles in infants and in the secretion process of mammary glands. However, few studies have evaluated miRNAs in dairy processes, such as during cheese making and ripening. Thus, we investigated the characteristics of milk-derived miRNAs during the manufacturing and ripening of Camembert cheese as well as the microbiota present using the quantitative reverse transcription polymer chain reaction (RT-qPCR) and 16S rRNA pyrosequencing, respectively. Pyrosequencing showed that the cheese microbiota changed dramatically during cheese processing, including during the pasteurization, starter culture, and ripening stages. Our results indicated that the RNA contents per $200mg/200{\mu}l$ of the sample increased significantly during cheese-making and ripening. The inner cheese fractions had higher RNA contents than the surfaces after 12 and 22 days of ripening in a time-dependent manner (21.9 and 13.2 times higher in the inner and surface fractions than raw milk, respectively). We performed a comparative analysis of the miRNAs in each fraction by RT-qPCR. Large amounts of miRNAs (miR-93, miR-106a, miR-130, miR-155, miR-181a, and miR-223) correlated with immune responses and mammary glands were present in aged cheese, with the exception of miR-223, which was not present on the surface. Considerable amounts of miRNAs were also detected in whey, which is usually disposed of during the cheese-making process. Unexpectedly, there were no significant correlations between immune-related miRNAs and the microbial populations during cheese processing. Taken together, these results show that various functional miRNAs are present in cheese during its manufacture and that they are dramatically increased in amount in ripened Camembert cheese, with differences according to depth.