MicroRNA miR-145 inhibits proliferation, invasiveness, and stem cell phenotype of an in vitro endometriosis model by targeting multiple cytoskeletal elements and pluripotency factors

Decreased expression of KLF6 in ectopic endometrial stromal cells contributes to endometriosis progression by targeting CTNNB1

Despite decades of research, endometriosis remains a mysterious gynecological disease with unknown etiology and pathogenesis. Krüppel-like Factor 6 (KLF6), a transcription factor, has a wide expression profile and regulates a variety of biological processes. Here, we investigated the expression and function of KLF6 and its possible regulatory mechanisms in endometriosis. To determine the function of KLF6, knockdown and overexpression experiments were performed in eutopic endometrial stromal cells (EU-ESCs) and ectopic endometrial stromal cells (EC-ESCs), respectively. Cell viability, apoptosis, migration, invasion, and angiogenesis assays were conducted in ESCs. ChIP-sequencing and mRNA-sequencing were performed to investigate the functional mechanism of KLF6 in regulating ESCs. We found that KLF6 was highly expressed in eutopic endometrium of endometriosis patients, compared with ectopic endometrium. Similarly, the same was true in EU-ESCs, which was compared with EC-ESCs. Overexpression of KLF6 significantly suppressed EC-ESC proliferation, migration and invasion and induced cell apoptosis, while knockdown of KLF6 resulted in the opposite effects on EU-ESCs. Overexpression of KLF6 significantly inhibited EC-ESC angiogenesis. Mechanistically, the results of ChIP sequencing and mRNA sequencing revealed that CTNNB1 may be a transcriptional target regulated by KLF6. Reintroduction of KLF6 reversed the effects of KLF6 knockdown on EU-ESCs. KLF6 inhibited the proliferation, migration and angiogenesis of EC-ESCs by inhibiting the expression of CTNNB1. Our findings provided a new perspective on the role of KLF6 in endometriosis progression and inspire potential targeted therapeutic strategies.

The outcome of tissue cryopreservation on the cellular, molecular and epigenetic characteristics of endometrial tissue and stromal cells

RESEARCH QUESTION

What impact does the cryopreservation of endometrial tissue have on cell characteristics and molecular and epigenetic profile changes in endometrial tissue and stromal cells?

DESIGN

Cellular properties, such as proliferation efficiency, surface marker expression and the differentiation potency of endometrial stromal cells (ESC) isolated from fresh (Native) and cryopreserved (Cryo) tissue were compared. Moreover, changes in the expression of genes associated with pluripotency, endometrial function and epigenetic regulation and microRNA (miRNA, miR) were assessed, as were levels of DNA methylation and histone modifications.

RESULTS

Native and Cryo cells exhibit very similar profiles including cell surface marker expression, differentiation potency and histone modifications, except for a decrease in proliferative potency and cell surface marker SUSD2 expression in Cryo cells. It was demonstrated that endometrial tissue cryopreservation led to an up-regulated expression of genes associated with pluripotency (NANOG, OCT4 [also known as POU5F1]). This confirms that despite being recovered from cryopreserved differentiated tissue, cells retained their stemness properties. In addition, alterations in DNA methyltransferase (DNMT1, DNMT3A, DNMT3B) gene regulation were observed, along with a down-regulation of hsa-miR145-5p in Cryo ESC.

CONCLUSIONS

These findings contribute to a deeper understanding of the complex effects of endometrial tissue cryopreservation, providing insights for both medical and basic research applications. Since different tissues possess unique characteristics, it is essential to select the most suitable cryopreservation method for each tissue individually. Furthermore, the study findings indicate the potential utility of slow-cooling cryopreservation for both normal and pathological endometrial tissue samples, with the purpose of isolating stromal cell cultures.

MiRNAs related in signaling pathways of women's reproductive diseases: an overview

BACKGROUND

One of the main health issues that can affect women's health is reproductive diseases, such as polycystic ovary syndrome (PCOS), endometriosis (EMs), uterine leiomyomas (ULs), and ovarian cancer (OC). Although these diseases are very common, we do not have a complete understanding of their underlying cellular and molecular mechanisms. It is important to mention that the majority of patients are diagnosed with these diseases at later stages because of the absence of early diagnostic techniques and dependable molecular indicators. Hence, it is crucial to discover novel and non-invasive biomarkers that have prognostic, diagnostic and therapeutic capabilities. MiRNAs, also known as microRNAs, are small non-coding RNAs that play a crucial role in regulating gene expression at the post-transcriptional level. They are short in length, typically consisting of around 22 nucleotides, and are highly conserved across species. Numerous studies have shown that miRNAs are expressed differently in various diseases and can act as either oncogenes or tumor suppressors.

METHODS

The author conducted a comprehensive review of all the pertinent papers available in web of science, PubMed, Google Scholar, and Scopus databases.

RESULTS

We achieved three goals: providing readers with better information, enhancing search results, and making peer review easier.

CONCLUSIONS

This review focuses on the investigation of miRNAs and their involvement in various reproductive disorders in women, including their molecular targets. Additionally, it explores the role of miRNAs in the development and progression of these disorders.

Role of Cyclins and Cytoskeletal Proteins in Endometriosis: Insights into Pathophysiology

Endometriosis is a gynecological condition where endometrium-like tissue grows outside the uterus, posing challenges in understanding and treatment. This article delves into the deep cellular and molecular processes underlying endometriosis, with a focus on the crucial roles played by cyclins and cytoskeletal proteins in its pathogenesis, particularly in the context of Epithelial-Mesenchymal Transition (EMT). The investigation begins by examining the activities of cyclins, elucidating their diverse biological roles such as cell cycle control, proliferation, evasion of apoptosis, and angiogenesis among ectopic endometrial cells. A comprehensive analysis of cytoskeletal proteins follows, emphasizing their fundamental biological roles and their specific significance to endometriotic cell features. This review sheds light on the interconnected pathways through which cyclins and cytoskeletal proteins converge, contributing to the genesis and progression of endometriosis. Understanding these molecular complexities not only provides insight into the underlying causes of the disease but also holds promise for the development of specific therapeutic approaches, ushering in a new era in the management of this devastating disorder.

Game-theoretic link relevance indexing on genome-wide expression dataset identifies putative salient genes with potential etiological and diapeutics role in colorectal cancer

Diapeutics gene markers in colorectal cancer (CRC) can help manage mortality caused by the disease. We applied a game-theoretic link relevance Index (LRI) scoring on the high-throughput whole-genome transcriptome dataset to identify salient genes in CRC and obtained 126 salient genes with LRI score greater than zero. The biomarkers database lacks preliminary information on the salient genes as biomarkers for all the available cancer cell types. The salient genes revealed eleven, one and six overrepresentations for major Biological Processes, Molecular Function, and Cellular components. However, no enrichment with respect to chromosome location was found for the salient genes. Significantly high enrichments were observed for several KEGG, Reactome and PPI terms. The survival analysis of top protein-coding salient genes exhibited superior prognostic characteristics for CRC. MIR143HG, AMOTL1, ACTG2 and other salient genes lack sufficient information regarding their etiological role in CRC. Further investigation in LRI methodology and salient genes to augment the existing knowledge base may create new milestones in CRC diapeutics.

Impact of Musashi-1 and Musashi-2 Double Knockdown on Notch Signaling and the Pathogenesis of Endometriosis

The stem cell marker and RNA-binding protein Musashi-1 is overexpressed in endometriosis. Musashi-1-siRNA knockdown in Ishikawa cells altered the expression of stem cell related genes, such as OCT-4. To investigate the role of both human Musashi homologues (MSI-1 and MSI-2) in the pathogenesis of endometriosis, immortalized endometriotic 12-Z cells and primary endometriotic stroma cells were treated with Musashi-1- and Musashi-2-siRNA. Subsequently, the impact on cell proliferation, cell apoptosis, cell necrosis, spheroid formation, stem cell phenotype and the Notch signaling pathway was studied in vitro. Using the ENDOMET Turku Endometriosis database, the gene expression of stem cell markers and Notch signaling pathway constituents were analyzed according to localization of the endometriosis lesions. The database analysis demonstrated that expression of Musashi and Notch pathway-related genes are dysregulated in patients with endometriosis. Musashi-1/2-double-knockdown increased apoptosis and necrosis and reduced stem cell gene expression, cell proliferation, and the formation of spheroids. Musashi silencing increased the expression of the anti-proliferation mediator p21. Our findings suggest the therapeutic potential of targeting the Musashi–Notch axis. We conclude that the Musashi genes have an impact on Notch signaling and the pathogenesis of endometriosis through the downregulation of proliferation, stemness characteristics and the upregulation of apoptosis, necrosis and of the cell cycle regulator p21.

Knockdown hsa_circ_0063526 inhibits endometriosis progression via regulating the miR-141-5p / EMT axis and downregulating estrogen receptors

Endometriosis can cause severe social burdens. Abnormal circular RNA levels have been found to lead to changes of related gene expression, thereby mediating the occurrence and development of a series of diseases, including endometriosis. The role of circRNA in endometriosis is still in its infancy. This study will explore the role of circRNA hsa_circ_0063526 with microRNA-141-5p in the development of endometriosis. The expression levels of genes were detected by RT-qPCR. Transwell, wound-healing, and EdU assays were performed on the End1 / E6E7 cell line from the endometriosis patient. PCR and immunohistochemistry were used to detect the expression of candidate regulatory genes in ectopic lesions in an endometriosis mice model. The expression level of hsa_circ_0063526 in ectopic tissue of endometriosis patients was significantly higher than control (P<0.05), The expression levels of hsa_circ_0063526 and miRNA-141-5P in ectopic tissue of endometriosis were negatively correlated (P<0.05). Knockdown of hsa_circ_0063526 inhibited the invasion, migration, and proliferation ability of End1 / E6E7 cell; the inhibition of microRNA-141-5p rescued this inhibition (P <0.05). In vivo experiments showed that miR-141-5p and si-hsa_circ_0063526 treatment reduced lesion size and regulated endometriosis genes. Our data suggest that hsa_circ_0063526 and miR-141-5p are possible biomarkers and therapeutic targets for endometriosis.

New Therapeutics in Endometriosis: A Review of Hormonal, Non-Hormonal, and Non-Coding RNA Treatments

Endometriosis is defined as endometrial-like tissue outside the uterine cavity. It is a chronic inflammatory estrogen-dependent disease causing pain and infertility in about 10% of women of reproductive age. Treatment nowadays consists of medical and surgical therapies. Medical treatments are based on painkillers and hormonal treatments. To date, none of the medical treatments have been able to cure the disease and symptoms recur as soon as the medication is stopped. The development of new biomedical targets, aiming at the cellular and molecular mechanisms responsible for endometriosis, is needed. This article summarizes the most recent medications under investigation in endometriosis treatment with an emphasis on non-coding RNAs that are emerging as key players in several human diseases, including cancer and endometriosis.

Diagnostic potential of differentially regulated microRNAs among endometriosis, endometrioid ovarian cancer, and endometrial cancer

Background

There is an increased risk of developing endometrioid ovarian and endometrial cancer in patients with endometriosis and there are no definitive diagnostic biomarkers available for these three associated diseases. Therefore, we evaluated the diagnostic potential of differentially expressed microRNAs (miRNAs) from the tissue samples of endometriosis, endometrioid ovarian cancer, and endometrial cancer to establish them as biomarkers for these diseases.

Materials and Methods

Ten samples of each, i.e., endometriosis, endometrioid ovarian cancer, endometrial cancer and control healthy endometrium were enrolled after obtaining ethical clearance. Differential expression of miR-16, miR-20a, miR-99b, miR-125a, miR-143, and miR-145 and some of their target genes, i.e., vascular endothelial growth factor (VEGF), hypoxia inducible factor 1A (HIF1A), cyclooxygenase 2 (COX2), and tumor necrosis factor (TNF) were quantified using quantitative reverse transcription polymerase chain reaction. Receiver operating characteristic (ROC) curve analysis was performed to predict the diagnostic potential.

Results

miR-16 and miR-20a were significantly downregulated, whereas miR-99b, miR-125a, and miR-143 were significantly upregulated in all three diseased samples. miR-145 was significantly upregulated in endometriosis and endometrioid ovarian cancer but significantly downregulated in endometrial cancer. mRNA levels of VEGF, HIF1A, COX2, and TNF were significantly increased in all three diseased samples as compared to control samples. ROC curve analysis revealed that for endometriosis, miR-99b, and miR-125a were giving highest area under curve (AUC) (0.950 and 0.733, respectively), for endometrioid carcinoma of ovary miR-143 was giving highest AUC (0.933) and for endometrioid endometrial cancer miR-16 (AUC = 0.815), miR-99b (AUC = 0.920), and miR-145 (AUC = 0.985) were found to be best predictors.

Conclusion

These findings suggest that these miRNAs can act as good predictors and discriminators of these three diseases and might serve as potential biomarkers for them.

HOX cluster and their cofactors showed an altered expression pattern in eutopic and ectopic endometriosis tissues

Endometriosis is major gynecological disease that affects over 10% of women worldwide and 30%-50% of these women have pelvic pain, abnormal uterine bleeding and infertility. The cause of endometriosis is unknown and there is no definite cure mainly because of our limited knowledge about its pathophysiology at the cellular and molecular levels. Therefore, demystifying the molecular mechanisms that underlie endometriosis is essential to develop advanced therapies for this disease. In this regard, HOX genes are remarkable because of their critical role in endometrial development and receptivity during implantation, which is attributed to their ability to mediate some of the sex steroid functions during the reproductive period. Access to the expression profiles of these genes would provide the necessary information to uncover new genes for endometriosis and assist with disease diagnosis and treatment. In this study we demonstrate an altered expression pattern for the HOX clusters (A-D) and their cofactors in both eutopic and ectopic conditions compared to control tissue biopsies. Remarkably, most of the intensive changes occurred in eutopic samples from endometriosis patients compared to control tissue biopsies. Pathway analysis revealed the involvement of differentially expressed genes in cancer that correlate with an association between endometriosis and cancer. Our results suggest critical roles for the HOX cluster and their cofactors in endometriosis pathophysiology.

Role of repressed microRNAs in endometriosis

Endometriosis is a common, estrogen-dependent benign tumor that affect 3-10% women of reproductive age, and is characterized by the ectopic growth of endometrial tissue, which is found primarily in the rectovaginal septum, ovaries, and pelvic peritoneum. To date, accumulating evidence suggests that various epigenetic aberrations, including the expression of aberrant microRNAs (miRNAs), play definite roles in the pathogenesis of endometriosis. This review summarizes the recent findings on the aberrantly repressed miRNAs, as well as their potential roles regarding the pathogenesis of endometriosis.

Circulating miRNAs Related to Epithelial-Mesenchymal Transitions (EMT) as the New Molecular Markers in Endometriosis

Endometriosis is a chronic gynecological disease defined by the presence of endometrial-like tissue found outside the uterus, most commonly in the peritoneal cavity. Endometriosis lesions are heterogenous but usually contain endometrial stromal cells and epithelial glands, immune cell infiltrates and are vascularized and innervated by nerves. The complex etiopathogenesis and heterogenity of the clinical symptoms, as well as the lack of a specific non-invasive diagnostic biomarkers, underline the need for more advanced diagnostic tools. Unfortunately, the contribution of environmental, hormonal and immunological factors in the disease etiology is insufficient, and the contribution of genetic/epigenetic factors is still fragmentary. Therefore, there is a need for more focused study on the molecular mechanisms of endometriosis and non-invasive diagnostic monitoring systems. MicroRNAs (miRNAs) demonstrate high stability and tissue specificity and play a significant role in modulating a range of molecular pathways, and hence may be suitable diagnostic biomarkers for the origin and development of endometriosis. Of these, the most frequently studied are those related to endometriosis, including those involved in epithelial–mesenchymal transition (EMT), whose expression is altered in plasma or endometriotic lesion biopsies; however, the results are ambiguous. Specific miRNAs expressed in endometriosis may serve as diagnostics markers with prognostic value, and they have been proposed as molecular targets for treatment. The aim of this review is to present selected miRNAs associated with EMT known to have experimentally confirmed significance, and discuss their utility as biomarkers in endometriosis.

Loss of TARBP2 Drives the Progression of Hepatocellular Carcinoma via miR-145-SERPINE1 Axis

The clinical outcomes of hepatocellular carcinoma (HCC) remain dismal. Elucidating the molecular mechanisms for the progression of aggressive HCC holds the promise for developing novel intervention strategies. The transactivation response element RNA-binding protein (TRBP/TARBP2), a key component of microRNA (miRNA) processing and maturation machinery has been shown to play conflicting roles in tumor development and progression. We sought to investigate the expression of TARBP2 in HCC using well-characterized HCC cell lines, patient-derived tissues and blood samples. Additionally, the potential prognostic and diagnostic value of TARBP2 in HCC were analyzed using Kaplan-Meier plots and ROC curve. Cell counting kit-8 (CCK-8), wound healing and transwell assays examined the ability of TARBP2 to induce cell proliferation, migration, and invasion in HCC cell lines. RNA sequencing was applied to identify the downstream elements of TARBP2. The interaction of potential targets of TARBP2, miR-145 and serpin family E member 1 (SERPINE1), was assessed using luciferase reporter assay. TARBP2 expression was down-regulated in HCC cell lines relative to normal hepatocyte cells, with a similar pattern further confirmed in tissue and blood samples. Notably, the loss of TARBP2 was demonstrated to promote proliferation, migration, and invasion in HCC cell lines. Interestingly, the reduction of TARBP2 was shown to result in the upregulation of SERPINE1, also known as plasminogen activator inhibitor (PAI-1), which is a vital gene of the HIF-1 signaling pathway. Knockdown of SERPINE1 rescued the TARBP2-lost phenotype. Moreover, TARBP2 depletion induced the upregulation of SERPINE1 through reducing the processing of miR-145, which directly targets SERPINE1. Finally, overexpression of miR-145 repressed SERPINE1 and rescued the functions in sh-TARBP2 HCC cells. Our findings underscore a linear TARBP2-miR-145-SERPINE1 pathway that drives HCC progression, with the potential as a novel intervention target for aggressive HCC.

The ellagic acid metabolites urolithin A and B differentially affect growth, adhesion, motility, and invasion of endometriotic cells in vitro

STUDY QUESTION

What are the effects of plant-derived antioxidant compounds urolithin A (UA) and B (UB) on the growth and pathogenetic properties of an in vitro endometriosis model?

SUMMARY ANSWER

Both urolithins showed inhibitory effects on cell behavior related to the development of endometriosis by differentially affecting growth, adhesion, motility, and invasion of endometriotic cells in vitro.

WHAT IS KNOWN ALREADY

Endometriosis is one of the most common benign gynecological diseases in women of reproductive age and is defined by the presence of endometrial tissue outside the uterine cavity. As current pharmacological therapies are associated with side effects interfering with fertility, we aimed at finding alternative therapeutics using natural compounds that can be administered for prolonged periods with a favorable side effects profile.

STUDY DESIGN, SIZE, DURATION

In vitro cultures of primary endometriotic stromal cells from 6 patients subjected to laparoscopy for benign pathologies with histologically confirmed endometriosis; and immortalized endometrial stromal (St-T1b) and endometriotic epithelial cells (12Z) were utilized to assess the effects of UA and UB on endometriotic cell properties. Results were validated in three-dimensional (3D) in vitro co-culture spheroids of 12Z and primary endometriotic stroma cells of one patient, and organoids from 3 independent donors with endometriosis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The effects on cell growth were measured by non-radioactive colorimetric assay to measure cellular metabolic activity as an indicator of cell viability (MTT assay) and flow cytometric cell cycle assay on primary cultures, St-T1b, and 12Z. Apoptosis analyses, the impact on in vitro adhesion, migration, and invasion were evaluated in the cell lines. Moreover, Real-Time Quantitative Reverse Transcription polymerase chain reaction (RT-qPCR) assays were performed on primary cultures, St- T1b and 12Z to evaluate a plausible mechanistic contribution by factors related to proteolysis (matrix metalloproteinase 2, 3 and 9 -MMP2, MMP3, MMP9-, and tissue inhibitor of metalloproteinases -TIMP-1-), cytoskeletal regulators (Ras-related C3 botulinum toxin substrate 1 -RAC1-, Rho-associated coiled-coil containing protein kinase 2 -ROCK2-), and cell adhesion molecules (Syndecan 1 -SDC1-, Integrin alpha V-ITGAV-). Finally, the urolithins effects were evaluated on spheroids and organoids by formation, viability, and drug screen assays.

MAIN RESULTS AND THE ROLE OF CHANCE

40 µM UA and 20 µM UB produced a significant decrease in cell proliferation in the primary endometriotic cell cultures (P < 0.001 and P < 0.01, respectively) and in the St-T1b cell line (P < 0.001 and P < 0.05, respectively). In St-T1b, UA exhibited a mean half-maximum inhibitory concentration (IC50) of 39.88 µM, while UB exhibited a mean IC50 of 79.92 µM. Both 40 µM UA and 20 µM UB produced an increase in cells in the S phase of the cell cycle (P < 0.01 and P < 0.05, respectively). The same concentration of UA also increased the percentage of apoptotic ST-t1b cells (P < 0.05), while both urolithins decreased cell migration after 24 h (P < 0.001 both). Only the addition of 5 µM UB decreased the number of St-T1b adherent cells. TIMP-1 expression was upregulated in response to treating the cells with 40 µM UA (P < 0.05). Regarding the 12Z endometriotic cell line, only 40 µM UA decreased proliferation (P < 0.01); while both 40 µM UA and 20 µM UB produced an increase in cells in the G2/M phase (P < 0.05 and P < 0.01, respectively). In this cell line, UA exhibited a mean IC50 of 40.46 µM, while UB exhibited a mean IC50 of 54.79 µM. UB decreased cell migration (P < 0.05), and decreased the number of adherent cells (P < 0.05). Both 40 µM UA and 20 µM UB significantly decreased the cellular invasion of these cells; and several genes were altered when treating the cells with 40 µM UA and 10 µM UB. The expression of MMP2 was downregulated by UA (P < 0.001), and expression of MMP3 (UA P < 0.001 and UB P < 0.05) and MMP9 (P < 0.05, both) were downregulated by both urolithins. Moreover, UA significantly downregulated ROCK2 (P < 0.05), whereas UB treatment was associated with RAC1 downregulation (P < 0.05). Finally, the matrix adhesion receptors and signaling (co)receptors SDC1 and ITGAV were downregulated upon treatment with either UA or UB (P < 0.01 and P < 0.05, respectively in both cases). Regarding the effects of urolithins on 3D models, we have seen that they significantly decrease the viability of endometriosis spheroids (80 µM UA and UB: P < 0.05 both) as well as affecting their area (40 µM UA: P < 0.05, and 80 µM UA: P < 0.01) and integrity (40 µM UA and UB: P < 0.05, 80 µM UA and UB: P < 0.01). On the other hand, UA and UB significantly inhibited organoid development/outgrowth (40 and 80 µM UA: P < 0.0001 both; 40 µM UB: P < ns-0.05-0.001, and 80 µM UB: P < 0.01-0.001-0.001), and all organoid lines show urolithins sensitivity resulting in decreasing viability (UA exhibited a mean IC50 of 33.93 µM, while UB exhibited a mean IC50 of 52.60 µM).

LARGE-SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

This study was performed on in vitro endometriosis models.

WIDER IMPLICATIONS OF THE FINDINGS

These in vitro results provide new insights into the pathogenetic pathways affected by these compounds and mark their use as a potential new therapeutic strategy for the treatment of endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded EU MSCA-RISE-2015 project MOMENDO (691058). The authors have no conflicts of interest to declare.

hsa-miR-199a-3p Inhibits Motility, Invasiveness, and Contractility of Ovarian Endometriotic Stromal Cells

It is suggested that aberrantly expressed microRNAs are involved in the pathogenesis of endometriosis. Our previous study demonstrated that expression of the microRNA hsa-miR-199a-3p is attenuated in human endometriotic cyst stromal cells (ECSCs). The current study aimed to define the roles of hsa-miR-199a-3p in the development of endometriosis. ECSCs and normal endometrial stromal cells (NESCs) were isolated from ovarian endometrioma and normal endometrial tissues, respectively. We evaluated the effect of transfected hsa-miR-199a-3p on the migration, invasion, and contractility of ECSCs using Transwell migration assays, in vitro wound healing assays, Transwell invasion assays, and collagen gel contraction assays. We also examined the downstream target of hsa-miR-199a-3p with an online public database search and luciferase reporter assay. Expression of hsa-miR-199a-3p in ECSCs was significantly lower than that in NESCs, whereas the expression of p21-activated kinase 4 (PAK4) mRNA was significantly higher. Transfection of hsa-miR-199a-3p inhibited the migration, invasion, and contractility of ECSCs via inhibition of PAK4 mRNA expression. PAK4 was confirmed to be the direct target of hsa-miR-199a-3p. Transfection of PAK4 small interfering RNA and the PAK4 inhibitor PF-3758309 also inhibited ECSC migration, invasion, and contractility. These findings suggest that hsa-miR-199a-3p may act as a tumor suppressor in endometriosis development. Attenuation of hsa-miR-199a-3p expression was favorable for ECSCs to acquire the highly invasive, motile, and contractile characteristics of endometriotic cells and is involved in the development of endometriosis. Accordingly, PAK4 inhibitors may be promising for the treatment of endometriosis.

Collagen I triggers directional migration, invasion and matrix remodeling of stroma cells in a 3D spheroid model of endometriosis

Endometriosis is a painful gynecological condition characterized by ectopic growth of endometrial cells. Little is known about its pathogenesis, which is partially due to a lack of suitable experimental models. Here, we use endometrial stromal (St-T1b), primary endometriotic stromal, epithelial endometriotic (12Z) and co-culture (1:1 St-T1b:12Z) spheroids to mimic the architecture of endometrium, and either collagen I or Matrigel to model ectopic locations. Stromal spheroids, but not single cells, assumed coordinated directional migration followed by matrix remodeling of collagen I on day 5 or 7, resembling ectopic lesions. While generally a higher area fold increase of spheroids occurred on collagen I compared to Matrigel, directional migration was not observed in co-culture or in 12Z cells. The fold increase in area on collagen I was significantly reduced by MMP inhibition in stromal but not 12Z cells. Inhibiting ROCK signalling responsible for actomyosin contraction increased the fold increase of area and metabolic activity compared to untreated controls on Matrigel. The number of protrusions emanating from 12Z spheroids on Matrigel was decreased by microRNA miR-200b and increased by miR-145. This study demonstrates that spheroid assay is a promising pre-clinical tool that can be used to evaluate small molecule drugs and microRNA-based therapeutics for endometriosis.

Circular RNA as a potential diagnostic and/or therapeutic target for endometriosis

Endometriosis is a pathology form of endometrium that behaves in a similar way to malignancies, such as invasion and resistance to apoptosis. Circular RNAs (CircRNAs) are a class of noncoding RNAs that have several biological functions including, miRNA sponging, sequestering of proteins, enhancing parental gene expression and translation resulting in polypeptides. In this review, we highlighted the roles of circRNAs as potential diagnostic and therapeutic biomarkers in endometriosis. Moreover, we summarized the roles of circRNAs in the pathogenesis of endometriosis via different signaling pathways, such as the miRNA network and apoptosis.

MicroRNAs in endometriosis: biological function and emerging biomarker candidates†

MicroRNAs (miRNAs), a class of small noncoding RNA molecules, have been recognized as key post-transcriptional regulators associated with a multitude of human diseases. Global expression profiling studies have uncovered hundreds of miRNAs that are dysregulated in several diseases, and yielded many candidate biomarkers. This review will focus on miRNAs in endometriosis, a common chronic disease affecting nearly 10% of reproductive-aged women, which can cause pelvic pain, infertility, and a myriad of other symptoms. Endometriosis has delayed time to diagnosis when compared to other chronic diseases, as there is no current accurate, easily accessible, and noninvasive tool for diagnosis. Specific miRNAs have been identified as potential biomarkers for this disease in multiple studies. These and other miRNAs have been linked to target genes and functional pathways in disease-specific pathophysiology. Highlighting investigations into the roles of tissue and circulating miRNAs in endometriosis, published through June 2018, this review summarizes new connections between miRNA expression and the pathophysiology of endometriosis, including impacts on fertility. Future applications of miRNA biomarkers for precision medicine in diagnosing and managing endometriosis treatment are also discussed.

Interplay between Cellular and Molecular Mechanisms Underlying Inflammatory Bowel Diseases Development-A Focus on Ulcerative Colitis

Inflammatory bowel diseases (IBD) are defined by the continuous inflammation of the gastrointestinal tract. During inflammation, the number of pathogens in the intestinal epithelium increases, leading to inflammasome assembly. Inflammasome activation is meant to protect the intestinal epithelial barrier from further damage by maintaining homeostasis. Although its purpose is to protect the cells, excessive nucleotide-binding oligomerization domain-like receptor and pyrin domain-containing protein 3 (NLRP3) inflammasome assembly is responsible for the synthesis of a high number of pro-inflammatory cytokines. The activation of two crucial pathways, autophagy process, and unfolded protein response, is initiated for restoring homeostasis. Aberrant expression of miRNAs and lncRNAs also interfere with the pathogenic mechanisms of IBD, as these non-coding transcripts play key roles in regulation of biological processes, such as inflammation and immunity. This review thoroughly describes the cellular and molecular mechanism that trigger and perpetuate inflammation in ulcerative colitis (UC) patients.

Apoptotic functions of microRNAs in pathogenesis, diagnosis, and treatment of endometriosis

MicroRNAs or miRNAs are a component of the non-coding RNAs family which is engaged in many cellular functions such as cell proliferation, apoptosis, gene expression, signaling pathways, angiogenesis, and etc. Endometriosis is a malignant gynecologic disorder occurring in women before menopausal age. Pathogenesis of this illness is still a discussion subject between the scientists but in our knowledge, microRNAs can be one of the possible involved factors. The purpose of this paper is to investigate the role of apoptotic activities of miRNAs in endometriosis. Accumulative evidence has demonstrated the role of cell proliferation, apoptosis, and invasion in the progression of these diseases. In this review, we looked into the specific role of apoptosis and its related genes and pathways in endometriosis and tied to present an explanation of how miRNAs can affect endometriosis by their apoptotic activities. What we found is that a great extent of miRNAs is involved in this illness and they are responsible for repressing apoptosis and progression of the disease. As a result, miRNAs have two different usages in endometriosis: biomarkers and potential therapeutic targets. In this review we gathered a great amount of evidence to inquire into the role of micro RNAs in inducing apoptosis and how this mechanism can be exerted for therapeutic purposes for endometriosis.

Up-regulation of miR-145 may contribute to repeated implantation failure after IVF-embryo transfer by targeting PAI-1

RESEARCH QUESTION

Repeated implantation failure (RIF) is a major limiting factor in assisted reproductive technology. As miR-145 (also known as MIR145) is up-regulated in patients with RIF, this study asked, what is the molecular mechanism underlying the affect of miR-145 on embryo implantation in RIF?

DESIGN

Ishikawa cells were infected with lentivirus containing miR-145 and miR-145 NC. Massive transcriptome data analyses and bioinformatics analysis were used to search for a potential candidate target of miR-145. The expression of the potential candidate target was detected using quantitative reverse transcription PCR (qRT-PCR) and western blotting in the Ishikawa cells infected with lentivirus containing miR-145 or miR-145 NC. Subsequently, a dual luciferase reporter assay was performed to verify whether the potential candidate target was a novel direct target of miR-145. In addition, expression of PAI-1 (plasminogen activator inhibitor 1, also known as SERPINE1) in endometrial tissue from women with RIF and in control endometrial tissue was examined using qRT-PCR and immunohistochemistry.

RESULTS

Based on massive transcriptome data analyses and bioinformatics analysis, PAI-1 was regarded as a potential candidate target of miR-145. miR-145 overexpression was achieved in Ishikawa cells. PAI-1 was confirmed as a direct target of miR-145 by bioinformatic analysis, qRT-PCR, western blotting and dual luciferase reporter assay. Further, results from the clinical sample indicated that at both the mRNA and protein levels, PAI-1 expression was down-regulated in endometrial tissues from women with RIF compared with control group women, and this was negatively related to miR-145 expression.

CONCLUSIONS

The study results suggests that miR-145 may target and down-regulate PAI-1 expression and influence embryo implantation in women with RIF who are undergoing IVF.

Deciphering the Role of miRNAs in Endometriosis Pathophysiology Using Experimental Endometriosis Mouse Models

Endometriosis is an enigmatic disease for which we still have a poor understanding on how and why the disease develops. In recent years, miRNAs, small noncoding RNAs which regulate gene expression posttranscriptionally, have been evaluated for their role in endometriosis pathophysiology. This review will provide a brief summary on the role of miRNAs in endometrial physiology and pathophysiology as related to endometriosis. We will then discuss mouse models used in endometriosis research and the incorporation of some of these models in studies which examined the role of miRNAs in endometriosis pathophysiology. We conclude with providing future prospective on the role of mouse models in dissecting the role of miRNAs in endometriosis pathophysiology.

In-vitro models of human endometriosis

Endometriosis is one of the most common benign gynecological diseases in women of reproductive age worldwide. In past decades, a number of in-vitro models have been used to investigate the pathology and therapeutic methods for the treatment of endometriosis. The current review summarized the majority of currently available in-vitro models, which utilize a variety of cell or tissues types, including endometriotic cell lines, primary endometrial stromal cells, endometrial stem cells, endometrial explants, peritoneal explants and immune cells. These cells or tissues are cultured individually, co-cultured in 2D or 3D systems with various matrices or cultured in chicken chorioallantotic membranes and amniotic membranes culture systems. These models are able to represent one or more aspects of the process of endometriosis. These models are helpful and can be used to investigate the development of endometriosis and the underlying mechanisms of this disorder in detail, and help investigators select appropriate models for their experiments. Recently, the new concept of endometriosis as a fibrotic condition will lead research to investigate the differentiation of myofibroblasts and the development of fibrosis in endometriotic lesions, which will increase the development of novel models that can be used to investigate endometriotic fibrosis.

The Pathogenesis of Endometriosis: Molecular and Cell Biology Insights

The etiopathogenesis of endometriosis is a multifactorial process resulting in a heterogeneous disease. Considering that endometriosis etiology and pathogenesis are still far from being fully elucidated, the current review aims to offer a comprehensive summary of the available evidence. We performed a narrative review synthesizing the findings of the English literature retrieved from computerized databases from inception to June 2019, using the Medical Subject Headings (MeSH) unique ID term “Endometriosis” (ID:D004715) with “Etiology” (ID:Q000209), “Immunology” (ID:Q000276), “Genetics” (ID:D005823) and “Epigenesis, Genetic” (ID:D044127). Endometriosis may origin from Müllerian or non-Müllerian stem cells including those from the endometrial basal layer, Müllerian remnants, bone marrow, or the peritoneum. The innate ability of endometrial stem cells to regenerate cyclically seems to play a key role, as well as the dysregulated hormonal pathways. The presence of such cells in the peritoneal cavity and what leads to the development of endometriosis is a complex process with a large number of interconnected factors, potentially both inherited and acquired. Genetic predisposition is complex and related to the combined action of several genes with limited influence. The epigenetic mechanisms control many of the processes involved in the immunologic, immunohistochemical, histological, and biological aberrations that characterize the eutopic and ectopic endometrium in affected patients. However, what triggers such alterations is not clear and may be both genetically and epigenetically inherited, or it may be acquired by the particular combination of several elements such as the persistent peritoneal menstrual reflux as well as exogenous factors. The heterogeneity of endometriosis and the different contexts in which it develops suggest that a single etiopathogenetic model is not sufficient to explain its complex pathobiology.

α-Aminoisobutyric Acid-Containing Amphipathic Helical Peptide-Cyclic RGD Conjugation as a Potential Drug Delivery System for MicroRNA Replacement Therapy in Vitro

Replacement therapy with tumor suppressive microRNA (TS-miRNA) might be the next-generation oligonucleotide therapy; however, a novel drug delivery system (DDS) is required. Recently, we developed the cell-penetrating peptide, model amphipathic peptide with α-aminoisobutyric acid (MAP(Aib)), as a carrier for oligonucleotide delivery to cells. In this study, we examined whether a modified MAP(Aib) analogue, MAP(Aib)-cRGD, could be a DDS for TS-miRNA replacement therapy. MIR145-5p, a representative TS-miRNA especially in colorectal cancer, was selected. The MAP(Aib)-cRGD dose was adjusted for MIR145-5p delivery to cells using peripheral blood mononuclear cells and degradation analysis. AlexaFluor488-labeled MIR145-5p incorporation into cells and negative regulation of MIR145-5p-targeting genes demonstrated MAP(Aib)-cRGD's functionality as a miRNA DDS. Treating MIR145-5p with MAP(Aib)-cRGD also revealed various anticancer effects, such as cell viability, invasion inhibition, and apoptosis induction in WiDr cells. Altogether, these findings suggest that MAP(Aib)-cRGD could be a DDS for TS-miRNA replacement therapy, but in vivo investigations are required.

γ-Secretase inhibition affects viability, apoptosis, and the stem cell phenotype of endometriotic cells

INTRODUCTION

Stem cells mediate cyclic regeneration of the endometrium. The upregulated expression of receptors and modulators of the notch signaling pathway in endometriosis suggests an involvement in the pathogenetic process. Here, we investigated the effects of notch pathway inhibition by a γ-secretase inhibitor (GSI) on stemness-associated properties of the epithelial endometriotic cell line 12Z and of primary endometriotic stroma cells.

MATERIAL AND METHODS

12Z cells and primary endometriotic stroma cells of 7 patients were treated with or without GSI, and analyzed for changes in gene expression by TaqMan low-density arrays, quantitative PCR, and flow cytometry. The functional impact of GSI treatment was studied by MTT assay, cell cycle analysis, colony formation assay, annexin V apoptosis assay, and aldehyde dehydrogenase activity assays.

RESULTS

In 12Z cells, GSI treatment reduced aldehyde dehydrogenase activity and colony formation, and induced a shift to the G2/M phase of the cell cycle. Cell viability was decreased and apoptosis was increased in both cell models. GSI further induced transcriptional downregulation of the stemness-associated factors leukemia inhibitory factor receptor (LIFR), sex-determining region Y (SRY)- box 2, interferon-induced transmembrane protein 1, and hes-related family bHLH transcription factor with YRPW motif 1, in 12Z cells and in primary cell cultures. Downregulation of LIFR expression by GSI was confirmed at the protein level by flow cytometry.

CONCLUSIONS

Our in vitro data suggest that application of GSI may be a worthwhile approach in the treatment of endometriosis that warrants further investigation.

Uterine stem cells: from basic research to advanced cell therapies

BACKGROUND

Stem cell research in the endometrium and myometrium from animal models and humans has led to the identification of endometrial/myometrial stem cells and their niches. This basic knowledge is beginning to be translated to clinical use for incurable uterine pathologies. Additionally, the implication of bone marrow-derived stem cells (BMDSCs) in uterine physiology has opened the field for the exploration of an exogenous and autologous source of stem cells.

OBJECTIVE AND RATIONALE

In this review, we outline the progress of endometrial and myometrial stem/progenitor cells in both human and mouse models from their characterization to their clinical application, indicating roles in Asherman syndrome, atrophic endometrium and tissue engineering, among others.

SEARCH METHODS

A comprehensive search of PubMed and Google Scholar up to December 2017 was conducted to identify peer-reviewed literature related to the contribution of bone marrow, endometrial and myometrial stem cells to potential physiological regeneration as well as their implications in pathologies of the human uterus.

OUTCOMES

The discovery and main characteristics of stem cells in the murine and human endometrium and myometrium are presented together with the relevance of their niches and cross-regulation. The current state of advanced stem cell therapy using BMDSCs in the treatment of Asherman syndrome and atrophic endometrium is analyzed. In the myometrium, the understanding of genetic and epigenetic defects that result in the development of tumor-initiating cells in the myometrial stem niche and thus contribute to the growth of uterine leiomyoma is also presented. Finally, recent advances in tissue engineering based on the creation of novel three-dimensional scaffolds or decellularisation open up new perspectives for the field of uterine transplantation.

WIDER IMPLICATIONS

More than a decade after their discovery, the knowledge of uterine stem cells and their niches is crystalising into novel therapeutic approaches aiming to treat with cells those conditions that cannot be cured with drugs, particularly the currently incurable uterine pathologies. Additional work and improvements are needed, but the basis has been formed for this therapeutic application of uterine cells.

Endometriotic Mesenchymal Stem Cells Epigenetic Pathogenesis: Deregulation of miR-200b, miR-145, and let7b in A Functional Imbalanced Epigenetic Disease

Objective

Stem cell issue is a strong theory in endometriosis pathogenesis. It seems that endometriotic mesenchymal stem cells (MSCs) show different characteristics compared to the normal MSCs. Determined high proliferation and low differentiation/decidualization potential of endometriotic MSCs could be accompanied by their microRNAs deregulation influencing their fate and function. In this study for the first time, we evaluated the expression of miR-200b, miR-145, and let-7b in endometriotic compared to non-endometriotic MSCs. These microRNAs are involved in biological pathways related to proliferation and differentiation of stem cells. Their aberrant expressions can disturb the proliferation/ differentiation balance in stem cells, altering their function and causing various diseases, like endometriosis.

Materials and Methods

In this experimental study, MSCs were isolated from three endometriotic and three nonendometriotic eutopic endometrium, followed by their characterization and culture. Expression of miR-200b, miR-145, and let-7b was ultimately analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR).

Results

We found that the expression of miR-200b was up-regulated (P<0.0001) whereas the expression of miR-145 and let-7b was down-regulated (P<0.0001) in endometriotic MSCs in comparison with non-endometriotic normal controls.

Conclusion

Proliferation and differentiation are important dynamic balanced biological processes, while in equillibrium, they determine a healthy stem cell fate. It seems that they are deregulated in endometriotic MSCs and change their function. miR-200b, miR-145, and let-7b are deregulated during endometriosis and they have pivotal roles in the modulating proliferation and differentiation of stem cells. We found up-regulation of miR-200b and down-regulation of miR-145 and let-7b in endometriotic MSCs. These changes can increase self-renewal and migration, while decreasing differentiation of endometriotic MSCs. Our achievements emphasize previous findings on the importance of proliferation/ differentiation balance in MSCs and clarify the role of microRNAs as main players in faulty endometriotic stem cells development.

Progesterone-Induced miR-145/miR-143 Inhibits the Proliferation of Endometrial Epithelial Cells

Our previous study showed that progesterone (P4) can specifically regulate the expression of some microRNAs (miRNAs) in endometrial epithelium. In the present study, we verified the P4-dependent expression of miR-145/miR-143 in endometrial epithelial cells, explored the regulative mechanism of the P4 receptor (PR), and investigated their effects on the proliferation of endometrial epithelial cells. Our results showed that P4 can induce the expression of miR-145/143 in endometrial epithelial cells by acting on the PR A subtype. P4-induced miR-145/143 can inhibit the expression of cyclin D2 by binding to cyclin D2 mRNA 3'UTR. It can also inhibit cell proliferation in mouse endometrial epithelium by arresting the cell cycle during the G1-S checkpoint. Furthermore, miR-145 and miR-143 can inhibit the proliferation of human endometrial cancer cells. In conclusion, P4-induced miR-145/miR-143 is an important regulator in the proliferation of endometrial epithelial cells, and it can also inhibit the proliferation of human endometrial cancer cells. Our study indicates miRNAs are important mechanism of P4 in inhibiting the proliferation of endometrial epithelial cells. And these miRNAs are potential candidates for the diagnosis of endometrial cancer and therapeutic targets.

Non-coding RNAs in endometriosis: a narrative review

BACKGROUND

Endometriosis is a benign gynaecological disorder, which affects 10% of reproductive-aged women and is characterized by endometrial cells from the lining of the uterus being found outside the uterine cavity. However, the pathophysiological mechanisms causing the development of this heterogeneous disease remain enigmatic, and a lack of effective biomarkers necessitates surgical intervention for diagnosis. There is international recognition that accurate non-invasive diagnostic tests and more effective therapies are urgently needed. Non-coding RNA (ncRNA) molecules, which are important regulators of cellular function, have been implicated in many chronic conditions. In endometriosis, transcriptome profiling of tissue samples and functional in vivo and in vitro studies demonstrate that ncRNAs are key contributors to the disease process.

OBJECTIVE AND RATIONALE

In this review, we outline the biogenesis of various ncRNAs relevant to endometriosis and then summarize the evidence indicating their roles in regulatory pathways that govern disease establishment and progression.

SEARCH METHODS

Articles from 2000 to 2016 were selected for relevance, validity and quality, from results obtained in PubMed, MEDLINE and Google Scholar using the following search terms: ncRNA and reproduction; ncRNA and endometriosis; miRNA and endometriosis; lncRNA and endometriosis; siRNA and endometriosis; endometriosis; endometrial; cervical; ovary; uterus; reproductive tract. All articles were independently screened for eligibility by the authors.

OUTCOMES

This review integrates extensive information from all relevant published studies focusing on microRNAs, long ncRNAs and short inhibitory RNAs in endometriosis. We outline the biological function and synthesis of microRNAs, long ncRNAs and short inhibitory RNAs and provide detailed findings from human research as well as functional studies carried out both in vitro and in vivo, including animal models. Although variability in findings between individual studies exists, collectively, the extant literature justifies the conclusion that dysregulated ncRNAs are a significant element of the endometriosis condition.

WIDER IMPLICATIONS

There is a compelling case that microRNAs, long non-coding RNAs and short inhibitory RNAs have the potential to influence endometriosis development and persistence through modulating inflammation, proliferation, angiogenesis and tissue remodelling. Rapid advances in ncRNA biomarker discovery and therapeutics relevant to endometriosis are emerging. Unravelling the significance of ncRNAs in endometriosis will pave the way for new diagnostic tests and identify new therapeutic targets and treatment approaches that have the potential to improve clinical options for women with this disabling condition.

Micro-RNA-Regulated Proangiogenic Signaling in Arteriovenous Loops in Patients with Combined Vascular and Soft-Tissue Reconstructions: Revisiting the Nutrient Flap Concept

BACKGROUND

The placement of arteriovenous loops can enable microvascular anastomoses of free flaps when recipient vessels are scarce. In animal models, elevated fluid shear stress in arteriovenous loops promotes neoangiogenesis. Anecdotal reports in patients indicate that vein grafts used in free flap reconstructions of ischemic lower extremities are able to induce capillary formation. However, flow-stimulated angiogenesis has never been systematically investigated in humans, and it is unclear whether shear stress alters proangiogenic signaling pathways within the vascular wall of human arteriovenous loops.

METHODS

Eight patients with lower extremity soft-tissue defects underwent two-stage reconstruction with arteriovenous loop placement, and free flap anastomoses to the loops 10 to 14 days later. Micro-RNA (miRNA) and gene expression profiles were determined in tissue samples harvested from vein grafts of arteriovenous loops by microarray analysis and quantitative real-time polymerase chain reaction. Samples from untreated veins served as controls.

RESULTS

A strong deregulation of miRNA and gene expression was detected in arteriovenous loops, showing an overexpression of angiopoietic cytokines, oxygenation-associated genes, vascular growth factors, and connexin-43. The authors discovered inverse correlations along with validated and bioinformatically predicted interactions between angiogenesis-regulating genes and miRNAs in arteriovenous loops.

CONCLUSIONS

The authors' findings demonstrate that elevated shear stress triggers proangiogenic signaling pathways in human venous tissue, indicating that arteriovenous loops may have the ability to induce neoangiogenesis in humans. The authors' data corroborate the nutrient flap hypothesis and provide a molecular background for arteriovenous loop-based tissue engineering with potential clinical applications for soft-tissue defect reconstruction.

Molecular network of miR-1343 regulates the pluripotency of porcine pluripotent stem cells via repressing OTX2 expression

Porcine OTX2 was found to be highly activated in porcine iPS cells (piPSCs) that were reported by different laboratories worldwide. To reveal the regulatory function of OTX2 in porcine reprogrammed cells, we screened porcine miRNA-seq databases and found two miRNAs, miR-1343 and miR-545, that could specifically bind to 3'UTR of OTX2 and suppress endogenous OTX2 expression in piPSCs. Knockdown of OTX2 by miR-1343 and miR-545 could significantly increase the expression of SOX2 and ESRRB, but did not alter the expressions of OCT4 and KLF4, and improve the pluripotency of piPSCs. The promoter-based assays showed that OTX2 potentially bound to the promoter region of SOX2 and ESRRB and suppressed their expression. On the other hand, SOX2 could interact with OTX2 promoter. Ectopic expression of SOX2 could significantly decrease OTX2 promoter activity, showing that there is a negative feedback loop between SOX2 and OTX2. Additionally, SOX2 and ESRRB significantly stimulated miR-1343 expression in piPSCs, but OTX2 down regulated the expression of miR-1343 in either direct or indirect manners. In summary, this study demonstrates that there is a regulatory network mediated by miR-1343, in which downregulation of OTX2 by miR-1343 can elevate the expression of pluripotent genes that were then sustain the pluripotency of piPSCs.

Chitosan in Non-Viral Gene Delivery: Role of Structure, Characterization Methods, and Insights in Cancer and Rare Diseases Therapies

Non-viral gene delivery vectors have lagged far behind viral ones in the current pipeline of clinical trials of gene therapy nanomedicines. Even when non-viral nanovectors pose less safety risks than do viruses, their efficacy is much lower. Since the early studies to deliver pDNA, chitosan has been regarded as a highly attractive biopolymer to deliver nucleic acids intracellularly and induce a transgenic response resulting in either upregulation of protein expression (for pDNA, mRNA) or its downregulation (for siRNA or microRNA). This is explained as the consequence of a multi-step process involving condensation of nucleic acids, protection against degradation, stabilization in physiological conditions, cellular internalization, release from the endolysosome ("proton sponge" effect), unpacking and enabling the trafficking of pDNA to the nucleus or the siRNA to the RNA interference silencing complex (RISC). Given the multiple steps and complexity involved in the gene transfection process, there is a dearth of understanding of the role of chitosan's structural features (Mw and degree of acetylation, DA%) on each step that dictates the net transfection efficiency and its kinetics. The use of fully characterized chitosan samples along with the utilization of complementary biophysical and biological techniques is key to bridging this gap of knowledge and identifying the optimal chitosans for delivering a specific gene. Other aspects such as cell type and administration route are also at play. At the same time, the role of chitosan structural features on the morphology, size and surface composition of synthetic virus-like particles has barely been addressed. The ongoing revolution brought about by the recent discovery of CRISPR-Cas9 technology will undoubtedly be a game changer in this field in the short term. In the field of rare diseases, gene therapy is perhaps where the greatest potential lies and we anticipate that chitosans will be key players in the translation of research to the clinic.

Insights into the key roles of epigenetics in matrix macromolecules-associated wound healing

Extracellular matrix (ECM) is a dynamic network of macromolecules, playing a regulatory role in cell functions, tissue regeneration and remodeling. Wound healing is a tissue repair process necessary for the maintenance of the functionality of tissues and organs. This highly orchestrated process is divided into four temporally overlapping phases, including hemostasis, inflammation, proliferation and tissue remodeling. The dynamic interplay between ECM and resident cells exerts its critical role in many aspects of wound healing, including cell proliferation, migration, differentiation, survival, matrix degradation and biosynthesis. Several epigenetic regulatory factors, such as the endogenous non-coding microRNAs (miRNAs), are the drivers of the wound healing response. microRNAs have pivotal roles in regulating ECM composition during wound healing and dermal regeneration. Their expression is associated with the distinct phases of wound healing and they serve as target biomarkers and targets for systematic regulation of wound repair. In this article we critically present the importance of epigenetics with particular emphasis on miRNAs regulating ECM components (i.e. glycoproteins, proteoglycans and matrix proteases) that are key players in wound healing. The clinical relevance of miRNA targeting as well as the delivery strategies designed for clinical applications are also presented and discussed.

miR-31 and miR-145 as Potential Non-Invasive Regulatory Biomarkers in Patients with Endometriosis

Objective

Endometriosis is a prevalent gynecologic disease affecting 10% of women in reproductive age. Endometriosis is diagnosed by laparoscopy that was followed by histologic confirmation. Early diagnosis will lead to a more effective treatment with much less morbidity. As miR-31 and miR-145 are shown to be directly or indirectly correlated to biological processes involved in endometriosis, the aim of this study was to examine the association of miR-31 and miR-145 expression in plasma with the presence of endometriosis.

Materials and Methods

In this case control study, the plasma samples of 55 patients with endometriosis and 23 women without endometriosis were collected, extracted and analyzed by real time quantitative polymerase chain reaction (qPCR) for the expression of miR-145 and miR-31.

Results

Our findings showed that miR-31 expression levels in stage 3 or 4 and stage 1 or 2 were significantly down- regulated (less than 0.01-fold, P<0.05), while the expression level of miR-145 was significantly up-regulated in women with endometriosis in stage 1 or 2.

Conclusion

Different cellular biological processes, such as differentiation, proliferation, mitochondrial function, reactive oxygen species (ROS) production, invasion and decidualization, are deregulated in endometriosis. miR-31 and miR-145 are microRNAs (miRNAs) with potential roles, as shown in pathologies like cancers. We found that miR- 31 was under-expressed in patients with endometriosis, while miR-145 was over-expressed in stage 1 or 2, indicating that they were relatively down-regulated in the more severe forms. Our findings suggested that these two miRNAs may be considered as potential biomarkers with probable implications in early diagnosis and even follow-up of patients with endometriosis.

Musashi-2, a novel oncoprotein promoting cervical cancer cell growth and invasion, is negatively regulated by p53-induced miR-143 and miR-107 activation

Background

Although previous studies have shown promise for targeting Musashi RNA-binding protein 2 (MSI-2) in diverse tumors, the role and mechanism of MSI-2 for cervical cancer (CC) progression and the regulation of MSI-2 expression remains unclear.

Methods

Using gene expression and bioinformatic analysis, together with gain- and loss-of-function assays, we identified MSI-2 as a novel oncogenic driver and a poor prognostic marker in CC. We explored the regulation of c-FOS by MSI-2 via RNA-immunoprecipitation and luciferase assay, and confirmed a direct inhibition of MSI-2 by miR-143/miR-107 using luciferase assay. We assessed the effect of a natural antibiotic Mithramycin A on p53, miR-143/miR-107 and MSI-2 expression in CC cells.

Results

MSI-2 mRNA is highly expressed in CC tissues and its overexpression correlates with lower overall survival. MSI-2 promotes CC cell growth, invasiveness and sphere formation through directly binding to c-FOS mRNA and by increasing c-FOS protein expression. Furthermore, miR-143/miR-107 are two tumor suppressor miRNAs that directly bind and inhibit MSI-2 expression in CC cells, and downregulation of miR-143/miR-107 associates with poor patient prognosis. Importantly, we found that p53 decreases the expression of MSI-2 through elevating miR-143/miR-107 levels, and treatment with a natural antibiotic Mithramycin A increased p53 and miR-143/miR-107 expression and reduced MSI-2 expression, resulting in the inhibition of CC cell proliferation, invasion and sphere formation.

Conclusions

These results suggest that MSI-2 plays a crucial role in promoting the aggressive phenotypes of CC cells, and restoration of miR-143/miR-107 by Mithramycin A via activation of p53 may represent a novel therapeutic approach for CC.

miRNA expression profiling in formalin-fixed paraffin-embedded endometriosis and ovarian cancer samples

Endometriosis is an inflammatory pathology associated with a negative effect on life quality. Recently, this pathology was connected to ovarian cancer, in particular with endometrioid ovarian cancer. microRNAs (miRNAs) are a class of RNA transcripts ~19–22 nucleotides in length, the altered miRNA pattern being connected to pathological status. miRNAs are highly stable transcripts, and these can be assessed from formalin-fixed paraffin-embedded (FFPE) samples leading to the identification of miRNAs that could be developed as diagnostic and prognostic biomarkers, in particular those involved in malignant transformation. The aim of our study was to evaluate miRNA expression pattern in FFPE samples from endometriosis and ovarian cancer patients using PCR-array technology and also to compare the differential expression pattern in ovarian cancer versus endometriosis. For the PCR-array study, we have used nine macrodissected FFPE samples from endometriosis tissue, eight samples of ovarian cancers and five normal ovarian tissues. Quantitative real-time PCR (qRT-PCR) was used for data validation in a new patient cohort of 17 normal samples, 33 endometriosis samples and 28 ovarian cancer macrodissected FFPE samples. Considering 1.5-fold expression difference as a cut-off level and a P-value <0.05, we have identified four miRNAs being overexpressed in endometrial tissue, while in ovarian cancer 15 were differentially expressed (nine overexpressed and six downregulated). The expression level was confirmed by qRT-PCR for miR-93, miR-141, miR-155, miR-429, miR-200c, miR-205 and miR-492. Using the interpretative program Ingenuity Pathway Analysis revealed several deregulated pathways due to abnormal miRNA expression in endometriosis and ovarian cancer, which in turn is responsible for pathogenesis; this differential expression of miRNAs can be exploited as a therapeutic target. A higher number of altered miRNAs were detected in endometriosis versus ovarian cancer tissue, most of them being linked with epithelial-to-mesenchymal transition.

Matrix-Bound Nanovesicles Recapitulate Extracellular Matrix Effects on Macrophage Phenotype

The early macrophage response to biomaterials has been shown to be a critical and predictive determinant of downstream outcomes. When properly prepared, bioscaffolds composed of mammalian extracellular matrix (ECM) have been shown to promote a transition in macrophage behavior from a proinflammatory to a regulatory/anti-inflammatory phenotype, which in turn has been associated with constructive and functional tissue repair. The mechanism by which ECM bioscaffolds promote this phenotypic transition, however, is poorly understood. The present study shows that matrix-bound nanovesicles (MBV), a component of ECM bioscaffolds, are capable of recapitulating the macrophage activation effects of the ECM bioscaffold from which they are derived. MBV isolated from two different source tissues, porcine urinary bladder and small intestinal submucosa, were found to be enriched in miRNA125b-5p, 143-3p, and 145-5p. Inhibition of these miRNAs within macrophages was associated with a gene and protein expression profile more consistent with a proinflammatory rather than an anti-inflammatory/regulatory phenotype. MBV and their associated miRNA cargo appear to play a significant role in mediating the effects of ECM bioscaffolds on macrophage phenotype.

miR-143 and miR-145 disrupt the cervical epithelial barrier through dysregulation of cell adhesion, apoptosis and proliferation

Molecular mechanisms regulating preterm birth (PTB)-associated cervical remodeling remain unclear. Prior work demonstrated an altered miRNA profile, with significant increases in miR-143 and miR-145, in cervical cells of women destined to have a PTB. The study objective was to determine the effect of miR-143 and miR-145 on the cervical epithelial barrier and to elucidate the mechanisms by which these miRNAs modify cervical epithelial cell function. Ectocervical and endocervical cells transfected with miR-negative control, miR-143 or miR-145 were used in cell permeability and flow cytometry assays for apoptosis and proliferation. miR-143 and miR-145 target genes associated with cell adhesion, apoptosis and proliferation were measured. Epithelial cell permeability was increased in miR-143 and miR-145 transfected cervical epithelial cells. Cell adhesion genes, JAM-A and FSCN1, were downregulated with overexpression of miR-143 and miR-145. miR-143 and miR-145 transfection decreased cervical cell number by increasing apoptosis and decreasing cell proliferation through initiation of cell cycle arrest. Apoptosis genes, BCL2 and BIRC5, and proliferation genes, CDK1 and CCND2, were repressed by miR-143 and miR-145. These findings suggest that miR-143 and miR-145 play a significant role in cervical epithelial barrier breakdown through diverse mechanisms and could contribute to premature cervical remodeling associated with PTB.

Human microRNA-299-3p decreases invasive behavior of cancer cells by downregulation of Oct4 expression and causes apoptosis

PURPOSE

Oct4 was reported to be one of the most important pluripotency transcription factors in the biology of stem cells including cancer stem cells, and progressed malignant cells. Here we report the investigation of gene expression control of Oct4 by selected human microRNAs and the physiological effect of Oct4 silencing in invasive cancer cells.

METHODS AND RESULTS

High throughput luciferase activity assay revealed the microRNA-299-3p to be the most effective in reducing gene expression of Oct4, which was confirmed by Western blot analysis and Oct4 promoter activity in a target luciferase assay. Furthermore, it could be demonstrated that downregulation of Oct4 by microRNAs-299-3p in breast cancer and fibrosarcoma cells lead to a decreased invasiveness in a microfluidic chip assay. Additionally, microRNA-299-3p causes apoptosis in cancer cells. Comparison with Oct4 specific siRNA transfection confirmed that this effect is primary due to the blockade of Oct4 expression.

CONCLUSION

The results suggest that microRNA-299-3p is an interesting target for potential clinical use. It may be able to decrease invasive behaviour of carcinoma cells; or even kill these cells by causing apoptosis.

MicroRNAs and Endometriosis: Distinguishing Drivers from Passengers in Disease Pathogenesis

Endometriosis is a disease common in women of reproductive age, characterized by pelvic pain and infertility. Despite its prevalence, the factors and mechanisms which contribute to the development and survival of ectopic lesions remain uncertain. MicroRNAs (miRNAs) are small RNA molecules that regulate posttranscriptional gene regulation which have been proposed to contribute to the pathogenesis of many diseases including that of endometriosis. This review summarizes the results of initial studies describing differentially expressed miRNAs between endometriotic lesion tissue and eutopic endometrium. Focus then moves toward discussion of studies on examining function of differentially expressed miRNAs to determine if they play a permissive role (driver of the disease) in events conducive to endometriosis progression/survival. Included in this discussion are the potential targets of these miRNAs and how their mis-expression may contribute to the disease. Limitations and challenges faced in studying miRNAs and endometriosis pathogenesis and recommendations to overcome these hurdles are presented at the end.

Genetics and epigenetics in small intestinal neuroendocrine tumours

Neuroendocrine tumour of the small intestine (SI-NET), formerly known as midgut carcinoid tumour, is the most common small intestinal malignancy. The incidence is rising, with recent reports of 0.67 per 100 000 in the USA and 1.12 per 100 000 in Sweden. SI-NETs often present a challenge in terms of diagnosis and treatment, as patients often have widespread disease and are beyond cure by surgery. Somatostatin analogues provide the mainstay of medical treatment to control hormonal excess and increase the time to progression. Despite overall favourable prognosis (5-year overall survival of 65%), there is a need to find markers to identify both patients with worse outcome and new targets for therapy. Loss on chromosome 18 has been reported in 60-90% of SI-NETs, but mutated genes on this chromosome have failed detection. Recently, a putative tumour suppressor role has been suggested for TCEB3C occurring at 18q21 (encoding elongin A3), which may undergo epigenetic repression. CDKN1B has recently been revealed as the only recurrently mutated gene in SI-NETs but, with a frequency as low as 8%, its role as a driver in SI-NET development may be questioned. Integrated genomewide analysis including exome and whole-genome sequencing, gene expression, DNA methylation and copy number analysis has identified three novel molecular subtypes of SI-NET with differing clinical outcome. DNA methylation analysis has demonstrated that SI-NETs have significant epigenetic dysregulation in 70-80% of tumours. In this review, we focus on understanding of the genetic, epigenetic and molecular events that lead to development and progression of SI-NETs.