miR-483 is Down-Regulated in Polycystic Ovarian Syndrome and Inhibits KGN Cell Proliferation via Targeting Insulin-Like Growth Factor 1 (IGF1)

MiR-145-5p regulates granulosa cell proliferation by targeting the SET gene in KGN cells

MiR-145-5p has been implicated in the development and progression of various disorders, and it is primarily recognized as a tumor suppressor in numerous cancers types. Its expression has been reported to decrease in the granulosa cells of patients with polycystic ovarian syndrome (PCOS). This study aimed to investigate whether miR-145-5p plays a role in granulosa cell proliferation and to shed light on the underlying pathological mechanisms of follicular development in patients with PCOS. Follicular fluid samples were collected from patients with PCOS and healthy individuals. The Cell Counting Kit-8 and bromodeoxyuridine assays were performed to assess KGN cell proliferation. The expression of miR-145-5p was significantly decreased in PCOS granulosa cells than in control cells, whereas the expression of SET was increased. Furthermore, miR-145-5p suppressed the proliferation of KGN cells. SET was identified as a direct target of miR-145-5p. Additionally, SET promoted the proliferation of KGN cells, and knockdown of SET counteracted the effect of the miR-145-5p inhibitor. Therefore, miR-145-5p regulates granulosa cell proliferation by targeting the SET in KGN cells; this process may be a potential pathological pathway that contributes to follicular developmental disorders in PCOS.

Function of MicroRNAs in Normal and Abnormal Ovarian Activities: A Review Focus on MicroRNA-21

Some failures in ovary function, like folliculogenesis and oogenesis, can give rise to various infertility-associated problems, including polycystic ovary syndrome (PCOS) and premature ovarian insufficiency (POI). PCOS influences 8 to 20% of women; while POI occurs in at least 1% of all women. Regrettably, the current therapies for these diseases have not sufficiently been effective, and finding a suitable strategy is still a puzzle. One of the helpful strategies for managing and treating these disorders is understanding the contributing pathogenesis and mechanisms. Recently, it has been declared that abnormal expression of microRNAs (miRNAs), as a subset of non-coding RNAs, is involved in the pathogenesis of reproductive diseases. Among the miRNAs, the roles of miRNA-21 in the pathogenesis of PCOS and POI have been highlighted in some documents; hence, the purpose of this mini-review was to summarize the evidences in conjunction with the functions of this miRNA and other effective microRNAs in the normal or abnormal functions of the ovary (i.e., PCOS and POI) with a mechanistic insight.

A glance into the roles of microRNAs (exosomal and non-exosomal) in polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder in women of reproductive age. The clinical symptoms include hyperandrogenism, chronic anovulation, and multiple ovarian cysts. PCOS is strongly associated with obesity and insulin resistance. MicroRNAs (miRNAs) are a group of short non-coding RNAs that play a role in the post-transcriptional regulation of gene expression and translational inhibition. They play a vital role in the regulation of multiple metabolic and hormonal processes as well as in oocyte maturation and folliculogenesis in the female reproductive system. miRNAs can be used as diagnostic biomarkers or therapeutic targets because of their stability. The encapsulation of miRNAs in extracellular vesicles or exosomes contributes to their stability. Exosomes are constantly secreted by many cells and size of about 30 to 150 nm. Enveloping miRNAs exosomes can release them for cellular communication. The induced transfer of miRNAs by exosomes is a novel process of genetic exchange between cells. Many studies have shown that along with non-exosomal miRNAs, different types of exosomal miRNAs derived from the serum and follicular fluid can play an essential role in PCOS pathogenesis. These miRNAs are involved in follicular development and various functions in granulosa cells, apoptosis, cell proliferation, and follicular atresia. The present study aimed to comprehensively review the evidence on miRNAs and their affected pathways under both non-exosomal and exosomal circumstances, primarily focusing on the pathogenesis of PCOS.

The Translational Role of miRNA in Polycystic Ovary Syndrome: From Bench to Bedside—A Systematic Literature Review

MicroRNAs (miRNAs) are small, non-coding RNAs that are essential for the regulation of post-transcriptional gene expression during tissue development and differentiation. They are involved in the regulation of manifold metabolic and hormonal processes and, within the female reproductive tract, in oocyte maturation and folliculogenesis. Altered miRNA levels have been observed in oncological and inflammatory diseases, diabetes or polycystic ovary syndrome (PCOS). Therefore, miRNAs are proving to be promising potential biomarkers. In women with PCOS, circulating miRNAs can be obtained from whole blood, serum, plasma, urine, and follicular fluid. Our systematic review summarizes data from 2010–2021 on miRNA expression in granulosa and theca cells; the relationship between miRNAs, hormonal changes, glucose and lipid metabolism in women with PCOS; and the potential role of altered miRNAs in fertility (oocyte quality) in PCOS. Furthermore, we discuss miRNAs as a potential therapeutic target in PCOS and as a diagnostic marker for PCOS.

A Brief Review on the Regulatory Roles of MicroRNAs in Cystic Diseases and Their Use as Potential Biomarkers

miRNAs are small endogenous conserved non-coding RNA molecules that regulate post-transcriptional gene expression through mRNA degradation or translational inhibition, modulating nearly 60% of human genes. Cystic diseases are characterized by the presence of abnormal fluid-filled sacs in the body, and though most cysts are benign, they can grow inside tumors and turn malignant. Recent evidence has revealed that the aberrant expression of a number of miRNAs present in extracellular fluids, including plasma or serum, urine, saliva, follicular fluid, and semen, contribute to different cystic pathologies. This review aims to describe the role of different miRNAs in three worldwide relevant cystic diseases: polycystic ovarian syndrome (PCOS), polycystic kidney disease (PKD), and pancreatic cyst tumors (PCTs), as well as their potential use as novel biomarkers.

A Brief Review on the Regulatory Roles of MicroRNAs in Cystic Diseases and Their Use as Potential Biomarkers

miRNAs are small endogenous conserved non-coding RNA molecules that regulate post-transcriptional gene expression through mRNA degradation or translational inhibition, modulating nearly 60% of human genes. Cystic diseases are characterized by the presence of abnormal fluid-filled sacs in the body, and though most cysts are benign, they can grow inside tumors and turn malignant. Recent evidence has revealed that the aberrant expression of a number of miRNAs present in extracellular fluids, including plasma or serum, urine, saliva, follicular fluid, and semen, contribute to different cystic pathologies. This review aims to describe the role of different miRNAs in three worldwide relevant cystic diseases: polycystic ovarian syndrome (PCOS), polycystic kidney disease (PKD), and pancreatic cyst tumors (PCTs), as well as their potential use as novel biomarkers.

A Brief Review on the Regulatory Roles of MicroRNAs in Cystic Diseases and Their Use as Potential Biomarkers

miRNAs are small endogenous conserved non-coding RNA molecules that regulate post-transcriptional gene expression through mRNA degradation or translational inhibition, modulating nearly 60% of human genes. Cystic diseases are characterized by the presence of abnormal fluid-filled sacs in the body, and though most cysts are benign, they can grow inside tumors and turn malignant. Recent evidence has revealed that the aberrant expression of a number of miRNAs present in extracellular fluids, including plasma or serum, urine, saliva, follicular fluid, and semen, contribute to different cystic pathologies. This review aims to describe the role of different miRNAs in three worldwide relevant cystic diseases: polycystic ovarian syndrome (PCOS), polycystic kidney disease (PKD), and pancreatic cyst tumors (PCTs), as well as their potential use as novel biomarkers.

Cellular Processes in Human Ovarian Follicles Are Regulated by Expression Profile of New Gene Markers—Clinical Approach

In the growing ovarian follicle, the maturing oocyte is accompanied by cumulus (CCs) and granulosa (GCs) cells. Currently, there remain many unanswered questions about the epithelial origin of these cells. Global and targeted gene transcript levels were assessed on 1, 7, 15, 30 days of culture for CCs and GCs. Detailed analysis of the genes belonging to epithelial cell-associated ontological groups allowed us to assess a total of 168 genes expressed in CCs (97 genes) and GCs (71 genes) during long-term in vitro culture. Expression changes of the analyzed genes allowed the identification of the group of genes: TGFBR3, PTGS2, PRKX, AHI1, and IL11, whose expression decreased the most and the group of ANXA3, DKK1, CCND1, STC1, CAV1, and SFRP4 genes, whose expression significantly increased. These genes’ expression indicates CCs and GCs epithelialization processes and their epithelial origin. Expression change analysis of genes involved in epithelization processes in GCs and CCs during their in vitro culture made it possible to describe the most significantly altered of the 11 genes. Detailed analysis of gene expression in these two cell populations at different time intervals confirms their ovarian surface epithelial origin. Furthermore, some gene expression profiles appear to have tumorigenic properties, suggesting that granulosa cells may play a role in cancerogenesis.

Circ_0043532 regulates miR-182/SGK3 axis to promote granulosa cell progression in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disease in women at childbearing age. Several circular RNAs (circRNAs) have been demonstrated to be involved in PCOS. In this study, we aimed to explore the function and mechanism of circ_0043532 in PCOS.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the expression of circ_0043532, miR-182 and serum/glucocorticoid regulated kinase family member 3 (SGK3). Cell proliferation was assessed by 5-ethynyl-2'-deoxyuridine (EdU) assay and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Flow cytometry analysis was employed to evaluate cell cycle and cell apoptosis. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to verify the association between miR-182 and SGK3. Western blot assay was carried out to determine the protein level of SGK3.

RESULTS

Circ_0043532 was markedly elevated in PCOS granulosa cells (GCs) and KGN cells. Silencing of circ_0043532 suppressed cell proliferation and cell cycle process and promoted cell apoptosis in PCOS GCs and KGN cells. For mechanistic analysis, circ_0043532 was identified as a sponge of miR-182 and SGK3 was confirmed to be a target gene of miR-182. Inhibition of miR-182 rescued the impacts of circ_0043532 interference on PCOS GCs and KGN cell progression. Moreover, miR-182 overexpression suppressed cell proliferation and cell cycle process and promoted cell apoptosis in PCOS GCs and KGN cells by targeting SGK3.

CONCLUSION

Deficiency of circ_0043532 suppressed cell proliferation and induced cell cycle arrest and cell apoptosis in PCOS by modulation of miR-182/SGK3 axis.

Downregulating lncRNA NEAT1 induces proliferation and represses apoptosis of ovarian granulosa cells in polycystic ovary syndrome via microRNA-381/IGF1 axis

OBJECTIVE

Researchers have revealed the combined functions of long noncoding RNAs (lncRNAs) and microRNA (miRNAs) in polycystic ovary syndrome (PCOS). This study aimed to understand the role of nuclear-enriched abundant transcript 1 (NEAT1) and miR-381 involving insulin-like growth factor 1 (IGF1) in PCOS.

METHODS

PCOS rat model was established by dehydroepiandrosterone induction. NEAT1, miR-381 and IGF1 expression in ovarian granulosa cells of PCOS patients and ovarian tissues of PCOS rats were tested. Bioinformatics website and dual luciferase reporter gene assay were utilized to verify the relationship between NEAT1 and miR-381 and that between miR-381 and IGF1. Levels of sex hormone, pathological changes and ovarian granulosa cell apoptosis in ovarian tissues of PCOS rats were detected. Ovarian granulosa cell proliferation and apoptosis were analyzed in vitro.

RESULTS

NEAT1 and IGF1 expression increased while miR-381 expression decreased in the ovarian granulosa cells of patients with PCOS and the ovarian tissues of PCOS rats. In in vivo experiments, interference with NEAT1 improved the levels of sex hormones, alleviated pathological changes and suppressed ovarian granulosa cell apoptosis in the ovarian tissues of PCOS rats. In in vitro cell experiments, interference with NEAT1 suppressed apoptosis and enhanced cell proliferation of ovarian granulosa cells. NEAT1 interference-mediated effect would be reversed by up-regulating miR-381. NEAT1 acted as a ceRNA to adsorb miR-381 to target IGF1. Overexpression of IGF1 reversed the inhibitory effect of miR-381 on ovarian granulosa cell apoptosis.

CONCLUSION

Interference with NEAT1 increases miR-381 and reduces IGF1 levels, effectively improving the levels of sex hormones and reducing the pathological damage of ovarian tissue in rats with PCOS.

Human Granulosa Cells-Stemness Properties, Molecular Cross-Talk and Follicular Angiogenesis

The ovarian follicle is the basic functional unit of the ovary, comprising theca cells and granulosa cells (GCs). Two different types of GCs, mural GCs and cumulus cells (CCs), serve different functions during folliculogenesis. Mural GCs produce oestrogen during the follicular phase and progesterone after ovulation, while CCs surround the oocyte tightly and form the cumulus oophurus and corona radiata inner cell layer. CCs are also engaged in bi-directional metabolite exchange with the oocyte, as they form gap-junctions, which are crucial for both the oocyte’s proper maturation and GC proliferation. However, the function of both GCs and CCs is dependent on proper follicular angiogenesis. Aside from participating in complex molecular interplay with the oocyte, the ovarian follicular cells exhibit stem-like properties, characteristic of mesenchymal stem cells (MSCs). Both GCs and CCs remain under the influence of various miRNAs, and some of them may contribute to polycystic ovary syndrome (PCOS) or premature ovarian insufficiency (POI) occurrence. Considering increasing female fertility problems worldwide, it is of interest to develop new strategies enhancing assisted reproductive techniques. Therefore, it is important to carefully consider GCs as ovarian stem cells in terms of the cellular features and molecular pathways involved in their development and interactions as well as outline their possible application in translational medicine.

MicroRNA-451a plays a role in polycystic ovary syndrome by regulating ovarian granulosa cell proliferation and apoptosis

The present study aimed to investigate whether microRNA (miR)-451a plays a role in polycystic ovary syndrome by regulating the biological function of ovarian granulosa cells and investigate the underlying molecular mechanism. In the present study, reverse transcription-quantitative PCR (RT-qPCR) analysis detected markedly low expression of miR-451a in KGN cells. TargetScan predicted that cyclic AMP-dependent transcription factor ATF-2 (ATF2) was a potential target gene of miR-451a, which was confirmed by a Dual-Luciferase reporter gene assay. Moreover, western blotting and RT-qPCR experiments indicated that ATF2 was significantly overexpressed in KGN cells. In addition, western blotting and RT-qPCR experiments were utilized to assess cell transfection efficiency, and it was found that miR-451a mimic significantly increased miR-451a expression in KGN cells. Subsequently, MTT assay was performed to detect cell proliferation and flow cytometry was utilized to detect cell apoptosis. Western blot and RT-qPCR assays were utilized to assess the protein and mRNA expression of ATF2 and cyclin D1. The results confirmed that miR-451a mimic significantly decreased ATF2 protein and mRNA expression in KGN cells, and this decrease was reversed by ATF2-plasmid co-transfection. Moreover, miR-451a mimic inhibited cell proliferation, enhanced cell apoptosis, reduced cyclin D1 expression, increased caspase-3 activity and cleaved caspase-3 protein levels, while it reduced pro-caspase 3 protein levels in KGN cells, and these effects were significantly reversed by ATF2-plasmid. The present preliminary results demonstrated that miR-451a regulated the proliferation and apoptosis of ovarian granulosa cells by targeting ATF2. Thus, the miR-451a/ATF2 axis may be a new potential target for the treatment of polycystic ovary syndrome.

The Interplay Between Non-coding RNAs and Insulin-Like Growth Factor Signaling in the Pathogenesis of Neoplasia

The insulin-like growth factors (IGFs) are polypeptides with similar sequences with insulin. These factors regulate cell growth, development, maturation, and aging via different processes including the interplay with MAPK, Akt, and PI3K. IGF signaling participates in the pathogenesis of neoplasia, insulin resistance, diabetes mellitus, polycystic ovarian syndrome, cerebral ischemic injury, fatty liver disease, and several other conditions. Recent investigations have demonstrated the interplay between non-coding RNAs and IGF signaling. This interplay has fundamental roles in the development of the mentioned disorders. We designed the current study to search the available data about the role of IGF-associated non-coding RNAs in the evolution of neoplasia and other conditions. As novel therapeutic strategies have been designed for modification of IGF signaling, identification of the impact of non-coding RNAs in this pathway is necessary for the prediction of response to these modalities.

The role of miRNAs in polycystic ovary syndrome with insulin resistance

PURPOSE

This review aims to summarize the key findings of several miRNAs and their roles in polycystic ovary syndrome with insulin resistance, characterize the disease pathogenesis, and establish a new theoretical basis for diagnosing, treating, and preventing polycystic ovary syndrome.

METHODS

Relevant scientific literature was covered from 1992 to 2020 by searching the PubMed database with search terms: insulin/insulin resistance, polycystic ovary syndrome, microRNAs, and metabolic diseases. References of relevant studies were cross-checked.

RESULTS

The related miRNAs (including differentially expressed miRNAs) and their roles in pathogenesis, and possible therapeutic targets and pathways, are discussed, highlighting controversies and offering thoughts for future directions.

CONCLUSION

We found abundant evidence on the role of differentially expressed miRNAs with its related phenotypes in PCOS. Considering the essential role of insulin resistance in the pathogenesis of PCOS, the alterations of associated miRNAs need more research attention. We speculate that race/ethnicity or PCOS phenotype and differences in methodological differences might lead to inconsistencies in research findings; thus, several miRNA profiles need to be investigated further to qualify for the potential therapeutic targets for PCOS-IR.

MicroRNA-Mediated Gene Regulatory Mechanisms in Mammalian Female Reproductive Health

Mammalian reproductive health affects the entire reproductive cycle starting with the ovarian function through implantation and fetal growth. Various environmental and physiological factors contribute to disturbed reproductive health status leading to infertility problems in mammalian species. In the last couple of decades a significant number of studies have been conducted to investigate the transcriptome of reproductive tissues and organs in relation to the various reproductive health issues including endometritis, polycystic ovarian syndrome (PCOS), intrauterine growth restriction (IUGR), preeclampsia, and various age-associated reproductive disorders. Among others, the post-transcriptional regulation of genes by small noncoding miRNAs contributes to the observed transcriptome dysregulation associated with reproductive pathophysiological conditions. MicroRNAs as a class of non-coding RNAs are also known to be involved in various pathophysiological conditions either in cellular cytoplasm or they can be released to the extracellular fluid via membrane-bounded extracellular vesicles and proteins. The present review summarizes the cellular and extracellular miRNAs and their association with the etiology of major reproductive pathologies including PCOS, endometritis, IUGR and age-associated disorders in various mammalian species.

Non-coding RNAs in polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

Genetic, environmental and epigenetical factors may play important roles in the pathogenesis of polycystic ovary syndrome (PCOS), however the etiology of PCOS remains unclear. Studies indicated that non-coding RNAs (ncRNAs) were involved in the occurrence and development of PCOS. Thus, we aim to perform a systematic review and meta-analysis to investigate the presence and dysregulated expression of ncRNAs in human PCOS.

METHODS

We searched in PubMed, Medline, Web of Science and Embase until July 2019 and summarized all eligible publications focusing on microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and small interfering RNAs (siRNAs) in PCOS.

RESULTS

Sixty-seven articles were included in our systematic review and 9 articles were included in meta-analysis. There is little overlap between studies when comparing miRNA profiles. Sensitivity analysis showed that the expression of miR-93 was upregulated in PCOS patients (WMD 0.75, P < 0.00001), without heterogeneity among remaining studies (I2 = 0%).

CONCLUSION

A large number of ncRNAs with altered levels were observed in plasma, serum, follicular fluid, granulosa cells or other issues from PCOS patients. Aberrant ncRNAs expression in PCOS may lead to aberrant steroidogenesis, adipocyte dysfunction, altered ovarian cell proliferation and/or apoptosis and have the potential to be used as diagnostic biomarkers.

Synergistic inhibition of csal1 and csal3 in granulosa cell proliferation and steroidogenesis of hen ovarian prehierarchical development†

SALL1 and SALL3 are transcription factors that play an essential role in regulating developmental processes and organogenesis in many species. However, the functional role of SALL1 and SALL3 in chicken prehierarchical follicle development is unknown. This study aimed to explore the potential role and mechanism of csal1 and csal3 in granulosa cell proliferation, differentiation, and follicle selection within the prehierarchical follicles of hen ovary. Our data demonstrated that the csal1 and csal3 transcriptions were highly expressed in granulosa cells of prehierarchical follicles, and their proteins were mainly localized in the cytoplasm of granulosa cells and oocytes as well as in the ovarian stroma and epithelium. It initially revealed that both csal1 and csal3 may be involved in chicken prehierarchical follicle development via a translocation mechanism. Furthermore, our results showed an abundance of CCND1, Bcat, StAR, CYP11A1, and FSHR mRNA in granulosa cells, and the proliferation levels of granulosa cells from the prehierarchical follicles were significantly increased by siRNA-mediated knockdown of csal1 or/and csal3. Conversely, the overexpression of csal1 or/and csal3 in the granulosa cells led to a remarkably decreased of them. Moreover, csal1 and csal3 together exert a much stronger effect on the regulation than any of csal1 or csal3. These results indicated that csal1 and csal3 play synergistic inhibitory roles on granulosa cell proliferation, differentiation, and steroidogenesis during prehierarchical follicle development in vitro. The current data provide a basis of molecular mechanisms of csal1 and csal3 in controlling the prehierarchical follicle development and growth of hen ovary in vivo.

MiR-483 induces senescence of human adipose-derived mesenchymal stem cells through IGF1 inhibition

Human adipose-derived mesenchymal stem cells (hADSCs) are an ideal source of seed cells for regenerative applications and tissue engineering. However, long-term in vitro culture of hADSCs reduces their quantity and quality, which lessens their value in research and clinical applications. The molecular mechanisms underlying this biological process are poorly defined. Recently identified microRNAs (miRNAs) have emerged as critical modulators of cellular senescence. In this study, we examined the changes in hADSCs undergoing senescence. Significant miR-483-3p upregulation was noted during in vitro passaging of hADSCs, which correlated with the adipogenic differentiation and cellular senescence. Knockdown of miR-483-3p retarded the adipogenic differentiation potential of hADSCs and reduced cellular senescence. Dual-luciferase reporter assays identified insulin-like growth factor-1 (IGF1) as the target gene of miR-483-3p. IGF1 inhibition confirmed its inhibitory effects on replicative senescence in hADSCs. In conclusion, our study revealed essential regulatory roles of miR-483-3p in the adipogenesis and aging of hADSCs mediated by targeting IGF1.

miR-155 is high-expressed in polycystic ovarian syndrome and promotes cell proliferation and migration through targeting PDCD4 in KGN cells

Polycystic ovarian syndrome (PCOS) is a typical disease of female endocrine and metabolic abnormalities. miR-155, famous as a multifunctional miRNA, promotes the proliferation, migration and invasion of human cancer cells. Therefore, we aimed to explore its regulation mechanism in PCOS. BrdU incorporation and apoptosis assay were used to test KGN cell survival. Luciferase activity experiment was employed to test targeting link between miR-155 and programmed cell death 4 (PDCD4). Migration and invasion assay were operated to examine the influence of miR-155 and PDCD4 in migration and invasion of KGN cells. In addition, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay and western blot analysis were utilized to measure expression of miR-155 and other relative factors. We found that expression of miR-155 was high in PCOS patients' tissues and it promoted proliferation, migration and invasion in KGN cells. Further studies found that PDCD4 was down-regulated by miR-155 and was a target of miR-155. Overexpression of PDCD4 promoted cell apoptosis to mitigate PCOS. Besides, up-regulation of PDCD4 suppressed PI3K/AKT and JNK signal pathways. To sum up, miR-155 promoted proliferation, migration, invasion and the activation of PI3K/AKT and JNK pathways in KGN cells through negatively regulating PDCD4.

LncRNA HCP5 promotes cell proliferation and inhibits apoptosis via miR-27a-3p/IGF-1 axis in human granulosa-like tumor cell line KGN

This study aimed to reveal the potential roles of long non-coding RNA HCP5 (lncRNA HCP5) and its potential molecular mechanism in polycystic ovarian syndrome (PCOS). The human granulosa-like tumor cell line KGN was used for assessing the effects of HCP5 in the proliferation and apoptosis of granulosa cells (GCs). The results showed that downregulation of HCP5 suppressed cell proliferation through arresting cell cycle progression at G1 phase, and induced the apoptosis via activating mitochondrial pathway, while overexpression of HCP5 played the opposite effects in KGN cells. We predicted and confirmed miR-27a-3p was a directly target to HCP5 and it could directly bind with insulin-like growth factor-1 (IGF-1). Next, we performed gain- and loss-of-functions approaches by transfecting miR-27a-3p inhibitor into HCP5 knocking down cells and transfecting miR-27a-3p mimics into HCP5 overexpressing cells. The results demonstrated that downregulation and upregulation of miR-27a-3p could block the effects on the proliferation and apoptosis mediated by silencing and overexpressing HCP5 in KGN cells. Additionally, miR-27a-3p inhibitor remarkably reversed the IGF-1 decrease regulated by knocking down HCP5 and miR-27a-3p mimics inhibited the IGF-1 increase modulated by overexpressing HCP5 in KGN cells. Furthermore, we observed that the promoted cell vitality and reduced apoptosis mediated by enforced expression of HCP5 could be alleviated when the KGN cells transfected with IGF-1 siRNA. Our findings indicate that HCP5 might be a potential regulatory factor for development of PCOS through regulating the miR-27a-3p/IGF-1 axis.

miR‑28‑5p suppresses cell proliferation and weakens the progression of polycystic ovary syndrome by targeting prokineticin‑1

Prokineticin‑1 (PROK1) serves important roles in the pathogenesis of polycystic ovary syndrome (PCOS); however, the association between microRNA (miR)‑28‑5p and PROK1 remains unclear. In the present study, the roles of miR‑28‑5p and PROK1, and their interaction in PCOS were investigated. Rat ovary granule cells were transfected with miR‑28‑5p mimics, and PROK1 expression levels were measured by reverse transcription‑quantitative PCR and western blotting. A dual‑luciferase reporter assay was performed to determine the association between miR‑28‑5p and PROK1. Additionally, pcDNA‑PROK1 was co‑transfected into rat ovary granule cells with miR‑28‑5p mimics. Cell proliferation, apoptosis, cell cycle and the expression of signaling proteins were investigated using Cell Counting Kit‑8 assays, 5‑ethynyl‑2'‑deoxyuridine staining, flow cytometry and western blotting, respectively. PROK1 expression was suppressed in rat ovary granule cells by miR‑28‑5p mimics, but upregulated following transfection with miR‑28‑5p inhibitors. The dual‑luciferase reporter assay revealed that miR‑28‑5p binds to the 3'‑untranslated region of PROK1. Proliferation activity was increased in PROK1‑overexpressing cells; this effect was eliminated by co‑transfection with miR‑28‑5p mimics. PROK1‑overexpressing rat ovary granule cells exhibited significantly suppressed cell apoptosis and a decreased number of cells in G1; miR‑28‑5p mimics reversed these effects. Western blotting revealed that the PI3K/AKT/mTOR signaling pathway was activated by PROK1. The present results suggested that miR‑28‑5p attenuated the progression of PCOS by targeting PROK1, which may promote the pathogenesis of PCOS via the PI3K/AKT/mTOR pathway, indicating that the miR‑28‑5p/PROK1 axis may be a potential therapeutic target for patients with PCOS.

Proliferation of Ovarian Granulosa Cells in Polycystic Ovarian Syndrome Is Regulated by MicroRNA-24 by Targeting Wingless-Type Family Member 2B (WNT2B)

BACKGROUND Polycystic ovarian syndrome (PCOS) is a common endocrine disorder causing infertility among reproductive-age women. The molecular mechanisms underlying the development of PCOS are not well understood, and effective treatment options and therapeutic targets for PCOS are not available. This study was designed to investigate the role and therapeutic potential of miR-324 in PCOS. MATERIAL AND METHODS We used quantitative real time-polymerase chain reaction (qRT-PCR) to assess expression. Cell viability was determined by [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Acridine orange/ethidium bromide (AO/EB) and annexin V/PI staining were performed to examine apoptosis. Western blot analysis was used to determine protein expression. RESULTS Results showed that the expression of miR-324 was aberrantly and significantly downregulated in PCOS ovarian tissues and KGN ovarian granulosa cells. Nonetheless, ectopic expression of miR-324 expression inhibited the viability of KGN cells via induction of apoptotic cell death. In silico analysis showed Wingless-Type family member 2B (WNT2B) to be the target of miR-324, which was also validated by dual-luciferase reporter assay. We also found that the expression of WNT2B was upregulated in the KGN cells, and overexpression of miR-324 inhibited WNT2B expression. Similar to WNT2B overexpression, WNT2B silencing decreased the viability of the KGN. Furthermore, overexpression of WNTB2 in KGN partially reversed the growth-inhibitory effects of miR-324 overexpression. CONCLUSIONS miR-324 regulates the proliferation of KGN cells in PCOs and be essential in the management of PCOS.

The role of MiRNA in polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in reproductive-aged women. Clinical manifestations include hyperandrogenism, chronic anovulation, polycystic ovaries and being frequently accompanied by insulin resistance (IR) and obesity. MicroRNAs (miRNAs) are short non-coding RNAs which are involved in the regulation of gene expression at the post-transcriptional level. Altered miRNAs levels have been showed to be associated with a variety of diseases including diabetes, endometriosis and cancer. In recent years, more and more evidence suggests abnormal expression of miRNAs are detected in granulosa cells, theca cells, adipose tissue, follicular fluid, serum and peripheral blood leukocytes of women with PCOS and display vital role in the occurrence and development of PCOS. This will shed light on new strategies for the diagnosis and treatment of this syndrome. In this paper, we will review the recent research on miRNAs with respect to PCOS.

The Role of microRNAs in Ovarian Granulosa Cells in Health and Disease

The granulosa cell (GC) is a critical somatic component of the ovary. It is essential for follicle development by supporting the developing oocyte, proliferating and producing sex steroids and disparate growth factors. Knowledge of the GC's function in normal ovarian development and function, and reproductive disorders, such as polycystic ovary syndrome (PCOS) and premature ovarian failure (POF), is largely acquired through clinical studies and preclinical animal models. Recently, microRNAs have been recognized to play important regulatory roles in GC pathophysiology. Here, we examine the recent findings on the role of miRNAs in the GC, including four related signaling pathways (Transforming growth factor-β pathway, Follicle-stimulating hormones pathway, hormone-related miRNAs, Apoptosis-related pathways) and relevant diseases. Therefore, miRNAs appear to be important regulators of GC function in both physiological and pathological conditions. We suggest that targeting specific microRNAs is a potential therapeutic option for treating ovary-related diseases, such as PCOS, POF, and GCT.

miR-483 inhibits bovine myoblast cell proliferation and differentiation via IGF1/PI3K/AKT signal pathway

MicroRNAs (miRNAs) have been established to regulate skeletal muscle development in mammals. However, few studies have been conducted on the regulation of proliferation and differentiation of bovine myoblast cells by miRNAs. The aim of our study was to explore the function of miR-483 in cell proliferation and differentiation of bovine myoblast. Here, we found that miR-483 declined in both proliferation and differentiation stages of bovine myoblast cells. During the proliferation phase, the overexpression of miR-483 downregulated the cell cycle-associated genes cyclin-dependent kinase 2 (CDK2), proliferating cell nuclear antigen (PCNA) messenger RNA (mRNA), and the protein levels. At the cellular level, cell cycle, cell counting kit-8, and 5-ethynyl-2´-deoxyuridine results indicated that the overexpression of miR-483 block cell proliferation. During differentiation, the overexpression of miR-483 led to a decrease in the levels of the myogenic marker genes MyoD1 and MyoG mRNA and protein. Furthermore, the immunofluorescence analysis results showed that the number of MyHC-positive myotubes was reduced. In contrast, the opposite experimental results were obtained concerning both proliferation and differentiation after the inhibition of miR-483. Mechanistically, we demonstrated that miR-483 target insulin-like growth factor 1 (IGF1) and downregulated the expression of key proteins in the PI3K/AKT signaling pathway. Altogether, our findings indicate that miR-483 acts as a negative regulator of bovine myoblast cell proliferation and differentiation.

Ovarian and Extra-Ovarian Mediators in the Development of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder affecting women of reproductive age. The origin of PCOS is still not clear and appears to be a function of gene x environment interactions. This review addresses the current knowledge of the genetic and developmental contributions to the etiology of PCOS, the ovarian and extra-ovarian mediators of PCOS and the gaps and key challenges that need to be addressed in the diagnosis, treatment and prevention of PCOS.

miR-323-3p regulates the steroidogenesis and cell apoptosis in polycystic ovary syndrome (PCOS) by targeting IGF-1

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic heterogeneous disorder. The incidence of which reaches 5% to 10% among reproductive-age women. Abnormal folliculogenesis is considered to be a common characteristic of PCOS, but the cause of this disorder and its pathogenesis still remain uncertain. Previous studies had proved that dysregulation of microRNAs is related to the pathogenesis of PCOS. In this study, we investigated the effect of miR-323-3p on the human cumulus cells (CCs). We also investigated the underlying mechanisms of miR-323-3p on human granulosa-like tumor cell line (KGN) or primary human CCs by stimulating with Dihydrotestosterone (DHT). Our findings suggested that the level of miR-323-3p in human CCs of women with PCOS was down-regulated, compared with that of the control group. Moreover, the inhibition of the level of miR-323-3p could up-regulate of the steroidogenesis and promote the apoptosis in KGN cells. In addition, our data confirmed that the Insulin-like growth factor 1 (IGF-1) gene was the direct target of miR-323-3p. Furthermore, the mimic of miR-323-3p inhibited the expression of IGF-1, which down-regulated the levels of AR, AMHR-II, CYP19A, EGFR, and GATA-4. In conclusion, miR-323-3p targeting IGF-1 regulates the steroidogenesis and the activity of CCs, which plays an important role in the occurrence and development of PCOS. Our results have shown that miR-323-3p is a novel and promising molecular target for the improvement of the dysfunction of CCs in PCOS.

Mir-483 inhibits colon cancer cell proliferation and migration by targeting TRAF1

MicroRNAs are important regulators during human growth and development. Emerging evidence indicates that microRNAs play important roles in colorectal cancer. The aim of this study is to reveal the biological function and direct target gene of miR-483 in colorectal cancer. The biological function of miR-483 on the proliferation and migration of colon cancer cells was then examined by Edu assay and transwell assay, respectively. Our findings revealed that miR-483 mimic could significantly inhibit cell proliferation and migration. The target gene of miR-483 was predicted by target scan software and identified by a dual fluorescence reporter system which showed that TRAF1 was a direct target gene of miR-483 in SW480 cell line. These data suggest that miR-483 is a colorectal cancer suppressor which could inhibit cell proliferation and migration, possibly via targeting TRAF1. The miR-483 could be a potential treatment target for colorectal cancer.

Functional Characterization of MicroRNA-27a-3p Expression in Human Polycystic Ovary Syndrome

The goal of this study was to characterize the function of microRNA-27a-3p (miR-27a-3p) in polycystic ovary syndrome (PCOS). miR-27a-3p expression was analyzed in excised granulosa cells (GCs) from 21 patients with PCOS and 12 normal patients undergoing in vitro fertilization cycle treatments and in 17 nontreated cuneiform ovarian resection PCOS samples and 13 control ovarian samples from patients without PCOS. We found that the expression of miR-27a-3p was significantly increased in both excised GCs and the ovaries of patients with PCOS compared with the controls. Insulin treatment of the human granulosa-like tumor cell line (KGN) resulted in decreased downregulated expression of miR-27a-3p, and this effect appeared to be mediated by signal transducer and activator of transcription STAT1 and STAT3. The overexpression of miR-27a-3p in KGN cells inhibited SMAD5, which in turn decreased cell proliferation and promoted cell apoptosis. After KGN cells were stimulated with insulin for 48 hours, there was increased expression of SMAD5 protein and decreased apoptosis. Additionally, knockdown/overexpression of SMAD5 in KGN cells reduced/increased cell number and promoted/inhibited cell apoptosis. Insulin-stimulated primary GCs isolated from patients with PCOS, in contrast to normal GCs or KGN cells, did not exhibit decreased miR-27a-3p expression. The differences in the expression levels in KGN cells and human PCOS GCs are likely explained by increased miR-27a-3p expression in the GCs caused by insulin resistance in PCOS. Taken together, our data provided evidence for a functional role of miR-27a-3p in the GCs' dysfunction that occurs in patients with PCOS.