miR-330-5p inhibits proliferation and migration of keratinocytes by targetingPdia3expression

Evolution of the ErbB gene family and analysis of regulators of Egfr expression during development of the rat spinal cord

Egfr, a member of the ErbB gene family, plays a critical role in tissue development and homeostasis, wound healing, and disease. However, expression and regulators of Egfr during spinal cord development remain poorly understood. In this study, we investigated ErbB evolution and analyzed co-expression modules, miRNAs, and transcription factors that may regulate Egfr expression in rats. We found that ErbB family members formed via Egfr duplication in the ancient vertebrates but diverged after speciation of gnathostomes. We identified a module that was co-expressed with Egfr, which involved cell proliferation and blood vessel development. We predicted 25 miRNAs and nine transcription factors that may regulate Egfr expression. Dual-luciferase reporter assays showed six out of nine transcription factors significantly affected Egfr promoter reporter activity. Two of these transcription factors (KLF1 and STAT3) inhibited the Egfr promoter reporter, whereas four transcription factors (including FOXA2) activated the Egfr promoter reporter. Real-time PCR and immunofluorescence experiments showed high expression of FOXA2 during the embryonic period and FOXA2 was expressed in the floor plate of the spinal cord, suggesting the importance of FOXA2 during embryonic spinal cord development. Considering the importance of Egfr in embryonic spinal cord development, wound healing, and disease (specifically in cancer), regulatory elements identified in this study may provide candidate targets for nerve regeneration and disease treatment in the future.

Circ_0060531 knockdown ameliorates IL-22-induced keratinocyte damage by binding to miR-330-5p to decrease GAB1 expression

BACKGROUND

Psoriasis is a chronic immune-mediated skin disease. Recent studies showed its pathogenesis involved circular RNA (circRNA). However, the role of circ_0060531 in psoriasis development and the behind mechanism remain to be explored.

METHODS

Psoriasis cell model was constructed by treating keratinocytes (HaCaT cells) using interleukin 22 (IL-22). Expression of circ_0060531, microRNA-330-5p (miR-330-5p) and GRB2 associated binder 1 (GAB1) was determined by quantitative real-time polymerase chain reaction. The functional effects of circ_0060531 on IL-22-caused cell injury were investigated by 3-(4,5-Dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide, 5-Ethynyl-29-deoxyuridine, wound-healing and enzyme-linked immunosorbent assays. Protein expression was analysed by Western blot. The interactions among circ_0060531, miR-330-5p and GAB1 were identified by dual-luciferase reporter or RNA immunoprecipitation assay.

RESULTS

Circ_0060531 and GAB1 expression were significantly increased, while miR-330-5p was decreased in psoriatic skin biopsies and IL-22-stimulated HaCaT cells in comparison with controls. In function, circ_0060531 knockdown assuaged IL-22-induced cell proliferation, cell migration and inflammation. Besides, circ_0060531 acted as a miR-330-5p sponge, and regulated the processes of IL-22-treated HaCaT cells by binding to the miRNA. Under the treatment of IL-22, miR-330-5p mediated HaCaT cell damage by targeting GAB1. Importantly, circ_0060531 modulated GAB1 production by interacting with miR-330-5p.

CONCLUSION

Circ_0060531 knockdown assuaged IL-22-induced keratinocyte dysfunction through miR-330-5p/GAB1 pathway, proving a novel target for the therapy of psoriasis.

Dysregulated expression and functions of microRNA-330 in cancers: A potential therapeutic target

As small non-coding RNAs, MicroRNAs (miRNAs) bind to the 3' untranslated region (3'-UTR) of mRNA targets to control gene transcription and translation. The gene of miR-330 has two miRNA products, including miR-330-3p and miR-330-5p, which exhibit anti-tumorigenesis and/or pro-tumorigenesis effects in many kinds of malignancies. In cancers, miR-330-3p and miR-330-5p aberrant expression can influence many malignancy-related processes such as cell proliferation, migration, invasion, apoptosis and epithelial-mesenchymal transition, as well as angiogenesis and responsiveness to treatment. In many cancer types (such as lung, prostate, gastric, breast, bladder, ovarian, colorectal, and pancreatic cancer, and osteosarcoma), miR-330-5p acts as an anti-tumor agent. These cancers have low levels of miR-330-5p that leads to the upregulation of the tumor promotor target genes leading to tumor progression. Here, overexpression of miR-330-5p using miRNA inducers can prevent tumor development. Dual roles of miR-330-5p have been also indicated in the thyroid, liver and cervical cancers. Moreover, miR-330-3p exhibits pro-tumorigenesis effects in lung cancer, pancreatic cancer, osteosarcoma, bladder cancer, and cervical cancer. Here, downregulation of miR-330-3p using miRNA inhibitors can prevent tumor development. Demonstrated in breast and liver cancers, miR-330-3p also has dual roles. Importantly, the activities of miR-330-3p and/or miR-330-5p are regulated by upstream regulators long non-coding RNAs (lncRNAs), including circular and linear lncRNAs. This review comprehensively explained miR-330-3p and miR-330-5p role in development of cancers, while highlighting their downstream target genes and upstream regulators as well as possible therapeutic strategies.

HLA class I antigen processing machinery defects in antitumor immunity and immunotherapy

Human leukocyte antigen (HLA) class I antigen-processing machinery (APM) plays a crucial role in the synthesis and expression of HLA class I tumor antigen-derived peptide complexes; the latter mediate the recognition and elimination of malignant cells by cognate T cells. Defects in HLA class I APM component expression and/or function are frequently found in cancer cells, providing them with an immune escape mechanism that has relevance in the clinical course of the disease and in the response to T-cell-based immunotherapy. The majority of HLA class I APM defects (>75%) are caused by epigenetic mechanisms or dysregulated signaling and therefore can be corrected by strategies that counteract the underlying mechanisms. Their application in oncology is likely to improve responses to T-cell-based immunotherapies, including checkpoint inhibition.

Weighted gene coexpression network and experimental analyses identify lncRNA SPRR2C as a regulator of the IL-22-stimulated HaCaT cell phenotype through the miR-330/STAT1/S100A7 axis

Psoriasis is a chronic inflammatory disease of the skin with highly complex pathogenesis. In this study, we identified lncRNA SPRR2C (small proline-rich protein 2C) as a hub gene with a critical effect on the pathogenesis of psoriasis and response to treatment using both weighted gene coexpression network analysis (WGCNA) and differential expression analysis. SPRR2C expression was significantly upregulated in both psoriatic lesion samples and HaCaT cell lines in response to IL-22 treatment. After SPRR2C knockdown, IL-22-induced suppression of HaCaT proliferation, changes in the KRT5/14/1/10 protein levels, and suppression of the IL-1β, IL-6, and TNF-α mRNA levels were dramatically reversed. In the coexpression network with SPRR2C based on GSE114286, miR-330 was significantly negatively correlated with SPRR2C, while STAT1 and S100A7 were positively correlated with SPRR2C. By binding to miR-330, SPRR2C competed with STAT1 and S100A7 to counteract miR-330-mediated suppression of STAT1 and S100A7. MiR-330 overexpression also reversed the IL-22-induced changes in HaCaT cell lines; in response to IL-22 treatment, miR-330 inhibition significantly attenuated the effects of SPRR2C knockdown. STAT1 and S100A7 expression was significantly upregulated in psoriatic lesion samples. The expression of miR-330 had a negative correlation with the expression of SPRR2C, while the expression of SPRR2C had a positive correlation with the expression of STAT1 and S100A7. Thus, SPRR2C modulates the IL-22-stimulated HaCaT cell phenotype through the miR-330/STAT1/S100A7 axis. WGCNA might uncover additional biological pathways that are crucial in the pathogenesis and response to the treatment of psoriasis.

The miR-93-3p/ZFP36L1/ZFX axis regulates keratinocyte proliferation and migration during skin wound healing

Keratinocyte proliferation and migration are crucial steps during skin wound healing. The functional role of microRNAs (miRs) remains relatively unknown during this process. miR-93 levels have been reported to increase within 24 h of skin wound healing; however, whether miR-93-3p or miR-93-5p plays a specific role in wound healing is yet to be studied. In this study, with the use of an in vivo mouse skin wound-healing model, we demonstrate that miR-93-3p is significantly upregulated, whereas there is no change in the expression of miR-93-5p during skin wound healing. In HaCaT cells, miR-93-3p overexpression increased proliferation and migration of the cells, whereas miR-93-3p inhibition had the reverse effect. Additionally, it was evident that ZFP36L1 was a direct target of miR-93-3p in keratinocytes. Further, ZFP36L1 silencing mirrored the consequences observed during miR-93-3p overexpression on both proliferation and migration of keratinocytes. In addition, we demonstrate that zinc-finger X-linked (ZFX), as a target for ZFP36L1, is involved in the promotion of the miR-93-3p/ZFP36L1 axis in keratinocyte proliferation and migration. Ultimately, we found that mouse skin wound model treatment with anti-miR-93-3p delayed wound healing. Overall, our results show that miR-93-3p is a crucial regulator of skin wound healing that facilitates keratinocyte proliferation and migration through ZFP36L1/ZFX axis.

Restoration of miR-330 expression suppresses lung cancer cell viability, proliferation, and migration

Lung cancer is one of the most common cancers and its incidence is rising around the world. Various studies suggest that miR-330 acts as a tumor-suppressor microRNA (miRNA) in different types of cancers, but precisely how has remained unclear. In this study, we investigate miR-330 expression in lung cancer patient samples, as well as in vitro, by studying how normalization of miR-330 expression affects lung cancer cellular phenotypes such as viability, apoptosis, proliferation, and migration. We establish that low miR-330 expression predicts poor lung cancer prognosis. Stable restoration of reduced miR-330 expression in lung cancer cells reduces cell viability, increases the fraction of apoptotic cells, causes G2/M cell cycle arrest, and inhibits cell migration. These findings are substantiated by increased mRNA and protein expression of markers for apoptosis via the intrinsic pathway, such as caspase 9, and decreased mRNA and protein expression of markers for cell migration, such as vimentin, C-X-C chemokine receptor type 4, and matrix metalloproteinase 9. We showed that reduced miR-330 expression predicts poor lung cancer survival and that stable restoration of miR-330 expression in lung cancer cells has a broad range of tumor-suppressive effects. This indicates that miR-330 is a promising candidate for miRNA replacement therapy for lung cancer patients.

Differential roles of exogenous protein disulfide isomerase A3 on proliferating cell and neuroblast numbers in the normal and ischemic gerbils

INTRODUCTION

We examined the effects of exogenous protein disulfide isomerase A3 (PDIA3) on hippocampal neurogenesis in gerbils under control and ischemic damage.

METHODS

To facilitate the delivery of PDIA3 to the brain, we constructed Tat-PDIA3 protein and administered vehicle (10% glycerol) or Tat-PDIA3 protein once a day for 28 days. On day 24 of vehicle or Tat-PDIA3 treatment, ischemia was transiently induced by occlusion of both common carotid arteries for 5 min.

RESULTS

Administration of Tat-PDIA3 significantly reduced ischemia-induced spontaneous motor activity, and the number of NeuN-positive nuclei in the Tat-PDIA3-treated ischemic group was significantly increased in the CA1 region compared to that in the vehicle-treated ischemic group. Ki67- and DCX-immunoreactive cells were significantly higher in the Tat-PDIA3-treated group compared to the vehicle-treated control group. In vehicle- and Tat-PDIA3-treated ischemic groups, the number of Ki67- and DCX-immunoreactive cells was significantly higher as compared to those in the vehicle- and Tat-PDIA3-treated control groups, respectively. In the dentate gyrus, the numbers of Ki67-immunoreactive cells were comparable between vehicle- and Tat-PDIA3-treated ischemic groups, while more DCX-immunoreactive cells were observed in the Tat-PDIA3-treated group. Transient forebrain ischemia increased the expression of phosphorylated cAMP-response element-binding protein (pCREB) in the dentate gyrus, but the administration of Tat-PDIA3 robustly increased pCREB-positive nuclei in the normal gerbils, but not in the ischemic gerbils. Brain-derived neurotrophic factor (BDNF) mRNA expression was significantly increased in the Tat-PDIA3-treated group compared to that in the vehicle-treated group. Transient forebrain ischemic increased BDNF mRNA levels in both vehicle- and Tat-PDIA3-treated groups, and there were no significant differences between groups.

CONCLUSIONS

These results suggest that Tat-PDIA3 enhances cell proliferation and neuroblast numbers in the dentate gyrus in normal, but not in ischemic gerbils, by increasing BDNF mRNA and phosphorylation of pCREB.

MicroRNA‑330‑5p inhibits osteosarcoma cell growth and invasion by targeting the proto‑oncogene survivin

Increasing evidence has suggested the crucial role of the dysregulation of microRNAs (miRNAs) in osteosarcoma (OS) progression. MicroRNA (miR)-330-5p has been reported to exert tumor suppressive effects in various types of human cancer. However, the role of miR-330-5p in the development of OS and the underlying mechanism remain to be clarified. In the present study, miR-330-5p expression was found to be significantly decreased in OS tissues and cell lines. In addition, low miR-330-5p expression was highly correlated with the overall survival and clinical stage of OS. Overexpression of miR-330-5p inhibited the viability, migration and invasion, and promoted the apoptosis of OS cells, as well as induced cell cycle arrest at the G₂/M phase. Subsequently, the proto-oncogene survivin was identified as a functional target of miR-330-5p, and this was validated using a luciferase reporter assay. It was also demonstrated that survivin expression was markedly increased in OS tissues, and that it was negatively correlated with the expression of miR-330-5p. Furthermore, overexpression of survivin significantly abrogated the tumor-suppressive effect induced by miR-330-5p on OS cells. In conclusion, these results revealed that the miR-330-5p/survivin axis has a significant tumor-suppressive effect on OS, and may serve as a diagnostic and therapeutic target for the treatment of OS.

miR-330 suppresses EMT and induces apoptosis by downregulating HMGA2 in human colorectal cancer

MicroRNAs (miRNAs) are important molecular regulatorsof cellular signaling and behavior. They alter gene expression by targeting messenger RNAs, including those encoding transcriptional regulators, such as HMGA2. While HMGA2 is oncogenic in various tumors, miRNAs may be oncogenic or tumor suppressive. Here, we investigate the expression of HMGA2 and the miRNA miR-330 in a patient with colorectal cancer (CRC) samples and their effects on oncogenic cellular phenotypes. We found that HMGA2 expression is increased and miR-330 expression is decreased in CRCs and each predicts poor long-term patient survival. Stably increased miR-330 expression in human colorectal cancer cells (HCT116) and SW480 CRC cell lines downregulate the oncogenic expression of HMGA2, a predicted miR-330 target. Additionally, this promotes apoptosis and decreases cell migration and viability. Consistently, it also decreases protein-level expression of markers for epithelial-to-mesenchymal-transition (Snail-1, E-cadherin, and Vascular endothelial growth factor receptors) and transforming growth factor β signaling (SMAD3), as well as phospho- Protein kinase B (AKT) and phospho-STAT3 levels. We conclude that miR-330 acts as a tumor suppressor miRNA in CRC by suppressing HMGA2 expression and reducing cell survival, proliferation, and migration. Thus, we identify miR-330 as a promising candidate for miRNA replacement therapy for patients with CRC.

Myalgic encephalomyelitis or chronic fatigue syndrome: how could the illness develop?

A model of the development and progression of chronic fatigue syndrome (myalgic encephalomyelitis), the aetiology of which is currently unknown, is put forward, starting with a consideration of the post-infection role of damage-associated molecular patterns and the development of chronic inflammatory, oxidative and nitrosative stress in genetically predisposed individuals. The consequences are detailed, including the role of increased intestinal permeability and the translocation of commensal antigens into the circulation, and the development of dysautonomia, neuroinflammation, and neurocognitive and neuroimaging abnormalities. Increasing levels of such stress and the switch to immune and metabolic downregulation are detailed next in relation to the advent of hypernitrosylation, impaired mitochondrial performance, immune suppression, cellular hibernation, endotoxin tolerance and sirtuin 1 activation. The role of chronic stress and the development of endotoxin tolerance via indoleamine 2,3-dioxygenase upregulation and the characteristics of neutrophils, monocytes, macrophages and T cells, including regulatory T cells, in endotoxin tolerance are detailed next. Finally, it is shown how the immune and metabolic abnormalities of chronic fatigue syndrome can be explained by endotoxin tolerance, thus completing the model.

Protective effects of microRNA-330 on amyloid β-protein production, oxidative stress, and mitochondrial dysfunction in Alzheimer's disease by targeting VAV1 via the MAPK signaling pathway

This study aims to explore the effect of miR-330 targeting VAV1 on amyloid β-protein (Aβ) production, oxidative stress (OS), and mitochondrial dysfunction in Alzheimer's disease (AD) mice through the MAPK signaling pathway. Putative targeted gene of miR-330 was performed by a miRNA target prediction website and dual-luciferase reporter gene assay. AD mouse model was successfully established. Fourteen C57 mice were randomized into AD and control groups. The positive protein expression rate of VAV1 was measured by immunohistochemistry. Neuron cells were assigned into control, blank, negative control (NC), miR-330 mimics, miR-330 inhibitors, siRNA-VAV1, and miR-330 inhibitors + siRNA-VAV1 groups. Expression of miR-330, VAV1, ERK1, JNK1, P38MAPK, Aβ, COX, and lipoprotein receptor-related protein-1 (LRP-1) were determined using RT-qPCR and Western blotting. Colorimetry was applied to measure the levels of OS parameters of superoxide dismutase (SOD) and malondialdehyde (MDA). Aβ production in brain tissue was detected using ELISA, while that in neuron cell was measured by radioimmunoassay. MiR-330 was down-regulated in neuron cells of AD mice and VAV1 was negatively regulated by miR-330. Compared with the control group, the positive protein expression rate of VAV1 was significantly elevated in the AD group. Overexpression of miR-330 decreased the expression of VAV1, ERK1, JNK1, P38MAPK, and Aβ, but increased the expression of COX and LRP-1. AD mice revealed elevated Aβ production and MDA with decreased SOD level. The result indicates that overexpressed miR-330 targeting VAV1 through the MAPK signaling pathway reduces Aβ production and alleviates OS and mitochondrial dysfunction in AD.

Long non-coding RNA EWSAT1 promotes human nasopharyngeal carcinoma cell growth in vitro by targeting miR-326/-330-5p

Long non-coding RNA (lncRNA) Ewing sarcoma associated transcript 1 (EWSAT1) has been identified as an oncogene, and its dysregulation is closed corrected with tumor progression in Ewing sarcoma. Recently, high-through put analysis reveals that EWSAT1 is also highly expressed in human nasopharyngeal carcinoma (NPC). However, whether the aberrant expression of EWSAT1 in NPC is corrected with malignancy or prognosis has not been expounded. Herein, we identified that EWSAT1 was up-regulated in NPC tissues and cell lines, and higher expression of EWSAT1 resulted in a markedly poorer survival time. EWSAT1 over-expression facilitated, while EWSAT1 silencing impaired cell growth in NPC. In addition, mechanistic analysis demonstrated that EWSAT1 up-regulated the expression of miR-326/330-5p clusters targeted gene cyclin D1 through acting as a competitive 'sponge' of miR-326/330-5p clusters. Collectively, our data revealed that EWSAT1 promotes NPC cell growth in vitro through up-regulating cyclin D1 partially via 'spongeing' miR-326/330-5p clusters.

Inhibition of NOB1 by microRNA-330-5p overexpression represses cell growth of non-small cell lung cancer

MicroRNAs (miRNAs) play critical roles in the development and progression of various cancers, including non-small-cell lung cancer (NSCLC). Studies have suggested that miR-330-5p is involved in the progression of several cancers. However, the role of miR-330-5p in NSCLC remains unclear. We investigated the effect on and mechanism of miR-330-5p in the progression of NSCLC. We found that miR-330-5p was significantly downregulated in NSCLC tissues and cell lines as detected by real-time quantitative polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), bromodeoxyuridine (BrdU), colony formation and cell cycle assays showed that overexpression of miR-330-5p markedly inhibited cell growth. Annexin V-FITC/PI and caspase-3 activity assays showed that overexpression of miR-330-5p significantly promoted cell apoptosis of NSCLC cells. Bioinformatics analysis and dual-luciferase reporter assays confirmed NIN/RPN12 binding protein 1 (NOB1) as a target gene of miR-330-5p. RT-qPCR and Western blot analysis showed that overexpression of miR-330-5p inhibited the expression of NOB1 as well as cyclin D1 and cyclin-dependent kinase 4 in NSCLC cells. Moreover, overexpression of NOB1 markedly reversed the miR‑330-5p-mediated inhibitory effect on NSCLC cell growth. Correlation analysis showed that miR‑330-5p expression was inversely correlated with NOB1 mRNA expression in NSCLC tissues. Taken together, our results indicate that miR-330-5p inhibits NSCLC cell growth through downregulation of NOB1 expression. Our study suggests that miR-330-5p may serve as a potential therapeutic target for the treatment of NSCLC.

miR-203a controls keratinocyte proliferation and differentiation via targeting the stemness-associated factor ΔNp63 and establishing a regulatory circuit with SNAI2

Keratinocyte differentiation plays a pivotal role in the function of epidermal barrier and can be triggered by extracellular calcium in vitro and in vivo, but the precise mechanism still need to be further investigated. On the other hand, it is known that microRNAs control multiple biological events including cellular proliferation and differentiation. The present study demonstrated that miR-203a expression was upregulated in calcium-induced HaCaT Cells in a dose-dependent manner, whereas the stemness-associated factors SNAI2 and ΔNp63 were downregulated. Furthermore, SNAI2 and ΔNp63 were identified as the targets of miR-203a by computational prediction and luciferase reporter assays. The protein levels of SNAI2 and ΔNp63 were suppressed by ectopic expression of miR-203a. Functionally, silencing of miR-203a or overexpression of SNAI2 and ΔNp63 attenuated cell cycle arrest induced by calcium without any changes in cellular apoptosis. Additionally, ectopic expression of SNAI2 inhibited miR-203a in calcium-induced HaCaT cells, by binding to the promoter region of miR-203a. In conclusion, our findings demonstrate that miR-203a plays an essential role in keratinocyte proliferation and differentiation caused by extracellular calcium by targeting the SNAI2 and ΔNp63 genes. Furthermore, SNAI2 was found to suppress the transcription of miR-203a. Our data highlights a coherent cross-talk between two transcription factors (SNAI2 and ΔNp63) and miR-203a in keratinocyte differentiation and epidermal development.

MiR-330 inhibits IL-22-induced keratinocyte proliferation through targeting CTNNB1

Psoriasis is a common chronic inflammatory skin disease which is characterized by hyperproliferation and aberrant differentiation of keratinocytes; however the exact pathogenesis is largely unknown. Interleukin-22 (IL-22) has demonstrated its vital role in T cell-mediated immune response by interacting with keratinocytes in the pathogenesis of psoriasis. The microRNAs (miRNAs) are a class of small non-coding RNA molecules that play important roles in cellular processes by regulating gene expression at the post-transcriptional level. MiR-330 has been reported to inhibit the proliferation and migration of mouse keratinocytes. In the present study, we indicated that miR-330 expression in lesion tissue of psoriasis patients was specifically down-regulated, and could inhibit IL-22-induced proliferation of HaCaT and HKC cell. Wnt/β-catenin pathway plays an essential role in the pathogenesis of psoriasis. By direct targeting CTNNB1, miR-330 could significantly downregulate IL-22-induced CTNNB1 expression. In addition, we found that the downstream targets of β-catenin, CyclinD1 and Axin2, could be affected by miR-330; miR-330 could suppress CyclinD1 protein expression and rescue Axin2 protein expression. Taken together, we indicated miR-330 inhibits IL-22-induced proliferation of HaCaT and HKC cell by targeting CTNNB1 and subsequently affect the downstream factors, CyclinD1 and Axin2 for the first time, and provide diagnostic markers and a novel target for psoriasis treatment.

Mouse-specific up-regulation of Ccnb1 expression by miR-199a-5p in keratinocyte

MicroRNA (miRNA) are a class of single-stranded, small non-coding RNA that regulate various biological processes, including skin and hair cycle regulation, by modulating the expression of specific genes at the post-transcriptional level. Recently, several studies reported that miRNA directly or indirectly up-regulate target genes. Previously, we performed microarray analysis to identify the target genes of miR-199a-5p in a mouse skin keratinocyte cell line and detected more than 200 genes whose expression was significantly increased by miR-199a-5p overexpression (> 1.5-fold). In this study, we further investigated these genes and found that cyclin B1 (Ccnb1) expression was positively regulated by miR-199a-5p in keratinocyte. Moreover, Ccnb1 expression was inversely correlated with miR-199a-5p expression during the mouse hair cycle. Cell cycle analysis showed that the proportion of cells in S phase was slightly increased, while the proportion of cells in G2/M phase decreased by miR-199-5p. Using luciferase assay, we found that the 3' untranslated region of Ccnb1 was a direct target of miR-199a-5p. We also found that the regulation of Ccnb1 expression by miR-199a-5p is mouse specific. CCNB1 expression was not affected in the human and monkey cell lines. These results provide a new relationship between Ccnb1 and miR-199a-5p in both mouse keratinocyte and miRNA biology.

Regulation of Srpr Expression by miR-330-5p Controls Proliferation of Mouse Epidermal Keratinocyte

Srpr is a gene encoding α subunit of the signal recognition particle receptor which is involved in the targeting and translocation of nascent secretory and membrane proteins to the endoplasmic reticulum. Previous studies showed aberrant expression of Srpr in several cell types with abnormal growth rate. Although Srpr is expressed in various tissues including skin, the role of Srpr in keratinocytes and regulation of its expression by miRNAs have not been studied. In this study, we investigated the role of SRPR and regulation of its expression by miRNA in skin keratinocytes. We found that SRPR was highly expressed in epidermal keratinocytes and regulated keratinocyte proliferation by affecting cell cycle progression. We also demonstrated that miR-330-5p directly inhibits Srpr expression. These data suggest that miR-330-5p-mediated regulation of the SRPR level is needed for the regulation of proliferation of epidermal keratinocytes.

Circulating MicroRNAs in Graves' Disease in Relation to Clinical Activity

BACKGROUND

Understanding the roles of circulating microRNAs (miRNAs) can provide important and novel information regarding disease pathogenesis and a patient's clinical condition. Circulating miRNAs, such as exosomal miRNA, may regulate various bioactivities related to intercellular communication. However, the circulation of miRNAs in Graves' disease (GD) in relation to disease activity has never been elucidated. This study aimed to identify circulating miRNAs in GD in relation to disease activity and whether their exosomes play a role in the pathogenesis of GD.

METHODS

Circulating miRNAs were measured in serum obtained from seven intractable GD patients, seven GD patients in remission, and seven healthy controls using the miScript miRNA PCR Array. Altered miRNAs selected from array data were validated in 65 subjects. To investigate exosome biology, peripheral blood mononuclear cells (PBMCs) were incubated with exosomes isolated from the subjects' sera. mRNAs were quantified for cytokines using quantitative real-time polymerase chain reaction.

RESULTS

Circulating miR-23b-5p and miR-92a-39 were increased in GD patients in remission compared with intractable GD patients (p < 0.05). On the other hand, let-7g-3p and miR-339-5p were decreased in GD patients in remission compared with intractable GD patients (p < 0.05). Exosomes from intractable GD patients stimulated mRNA expression for IL-1β and TNF-α compared with GD patients in remission or healthy controls.

CONCLUSIONS

This study demonstrates that different levels of circulating miRNAs are associated with intractable GD. Moreover, serum exosomes of patients with intractable GD may activate immune cells, which may play an important role in GD pathogenesis.

MiR-330-5p regulates tyrosinase and PDIA3 expression and suppresses cell proliferation and invasion in cutaneous malignant melanoma

BACKGROUND

Increasing evidence has suggested that miR-330-5p can function as a tumor suppressor in different types of cancers. However, the effects and underlying mechanisms of miR-330-5p in the development of cutaneous malignant melanoma (CMM) remain largely unknown. The aim of the present study was to investigate the role of miR-330-5p in CMM and to determine the molecular mechanisms underlying its action.

MATERIALS AND METHODS

The expression level of miR-330-5p was detected in 26 cases of primary CMM tissues and cell lines by real-time quantitative polymerase chain reaction. We also assessed whether overexpression of miR-330-5p influences in vitro cell proliferation, invasion, and migration. Western blotting analysis was used to detect the influence of miR-330-5p on the targets, and Pearson analysis was used to calculate the correlation between the expression of targets gene and miR-330-5p in CMM tissues.

RESULTS

Our study showed that miR-330-5p was downregulated in CMM tissues (P = 0.010) and cell lines (P < 0.05), and patients with high mitotic activity showed lower miR-330-5p expression levels (P = 0.002). Enforced expression of miR-330-5p inhibits malignant CMM cells proliferation and migration and led to downregulation of the TYR and PDIA3 protein. Moreover, the expression level of miR-330-5p in CMM tissues showed inverse relationship with the expression level of TYR and PDIA3 protein.

CONCLUSIONS

In conclusion, our findings suggested that miR-330-5p represents a potential tumor-suppressive miRNA and plays an important role in CMM progression by suppressing TYR and PDIA3 expression.

MiR-217 is down-regulated in psoriasis and promotes keratinocyte differentiation via targeting GRHL2

MiR-217 is a well-known tumor suppressor, and its down-regulation has been shown in a wide range of solid and leukaemic cancers. However, the biological role of miR-217 in psoriasis pathogenesis, especially in keratinocyte hyperproliferation and differentiation, is not clearly understood. In this study, we found the expression of miR-217 was markedly down-regulated in psoriasis keratinocytes of psoriatic patients. In addition, overexpression of miR-217 inhibited the proliferation and promoted the differentiation of primary human keratinocytes. On the contrary, inhibition of endogenous miR-217 increased cell proliferation and delayed differentiation. Furthermore, Grainyhead-like 2 (GRHL2) was identified as a direct target of miR-217 by luciferase reporter assay. The expression of miR-217 and GRHL2 was inversely correlated in both transfected keratinocytes and in psoriasis lesional skin. Moreover, knocking down GRHL2 expression by siRNA enhanced keratinocyte differentiation. Taken together, our results demonstrate a role for miR-217 in the regulation of keratinocyte differentiation, partially through the regulation of GRHL2.