Application of microRNA in diagnosis and treatment of ovarian cancer

A mAb against surface-expressed FSHR engineered to engage adaptive immunity for ovarian cancer immunotherapy

Despite advances in ovarian cancer (OC) therapy, recurrent OC remains a poor-prognosis disease. Because of the close interaction between OC cells and the tumor microenvironment (TME), it is important to develop strategies that target tumor cells and engage components of the TME. A major obstacle in the development of OC therapies is the identification of targets with expression limited to tumor surface to avoid off-target interactions. The follicle-stimulating hormone receptor (FSHR) has selective expression on ovarian granulosa cells and is expressed on 50%-70% of serous OCs. We generated mAbs targeting the external domain of FSHR using in vivo-expressed FSHR vector. By high-throughput flow analysis, we identified multiple clones and downselected D2AP11, a potent FSHR surface-targeted mAb. D2AP11 identifies important OC cell lines derived from tumors with different mutations, including BRCA1/2, and lines resistant to a wide range of therapies. We used D2AP11 to develop a bispecific T cell engager. In vitro addition of PBMCs and T cells to D2AP11-TCE induced specific and potent killing of different genetic and immune escape OC lines, with EC50s in the ng/ml range, and attenuated tumor burden in OC-challenged mouse models. These studies demonstrate the potential utility of biologics targeting FSHR for OC and perhaps other FSHR-positive cancers.

Recent advances of non-coding RNAs in ovarian cancer prognosis and therapeutics

Ovarian cancer (OC) is the third most common gynecological malignancy with the highest mortality worldwide. OC is usually diagnosed at an advanced stage, and the standard treatment is surgery combined with platinum or paclitaxel chemotherapy. However, chemoresistance inevitably appears coupled with the easy recurrence and poor prognosis. Thus, early diagnosis, predicting prognosis, and reducing chemoresistance are of great significance for controlling the progression and improving treatment effects of OC. Recently, much insight has been gained into the non-coding RNA (ncRNA) that is employed for RNAs but does not encode a protein, and many types of ncRNAs have been characterized including long-chain non-coding RNAs, microRNAs, and circular RNAs. Accumulating evidence indicates these ncRNAs play very active roles in OC progression and metastasis. In this review, we briefly discuss the ncRNAs as biomarkers for OC prognosis. We focus on the recent advances of ncRNAs as therapeutic targets in preventing OC metastasis, chemoresistance, immune escape, and metabolism. The novel strategies for ncRNAs-targeted therapy are also exploited for improving the survival of OC patients.

Myricetin Suppresses Ovarian Cancer In Vitro by Activating the p38/Sapla Signaling Pathway and Suppressing Intracellular Oxidative Stress

Ovarian cancer is a common malignancy with a mortality and effective, efficient treatments are urgently needed. Myricetin (Myr) is a flavonoid with antioxidant and anticancer properties. Here, we assessed Myr's toxicity on the non-tumor cell line, IOSE-80 and the mechanism by which it suppresses proliferation, migration, and invasion of ovarian cancer SKOV3 cells. The effects of Myr on SKOV3 cells were assessed using CCK-8, oxidative stress, wound healing, Transwell, Hoechst 33258 staining, and western blot assays. Our data show that although Myr was not toxic against IOSE-80 cells for a range of concentrations 0-40μM, it suppressed SKOV3 cell proliferation, migration, and invasion and enhanced apoptosis. Mechanistically, it activated the p38/Sapla signaling pathway, thereby inhibiting oxidative stress and reducing the level of ROS in tumor cells. Our data show that Myr suppresses ovarian cancer cells in vitro and suggests Myr as a candidate agent against ovarian cancer.

Simulation studies, 3D QSAR and molecular docking on a point mutation of protein kinase B with flavonoids targeting ovarian Cancer

BACKGROUND

Ovarian cancer is the world's dreaded disease and its prevalence is expanding globally. The study of integrated molecular networks is crucial for the basic mechanism of cancer cells and their progression. During the present investigation, we have examined different flavonoids that target protein kinases B (AKT1) protein which exerts their anticancer efficiency intriguing the role in cross-talk cell signalling, by metabolic processes through in-silico approaches.

METHOD

Molecular dynamics simulation (MDS) was performed to analyze and evaluate the stability of the complexes under physiological conditions and the results were congruent with molecular docking. This investigation revealed the effect of a point mutation (W80R), considered based on their frequency of occurrence, with AKT1 protein.

RESULTS

The ligand with high docking scores and favourable behaviour on dynamic simulations are proposed as potential W80R inhibitors. A virtual screening analysis was performed with 12,000 flavonoids satisfying Lipinski's rule of five according to which drug-likeness is predicted based on its pharmacological and biological properties to be active and taken orally. The pharmacokinetic ADME (adsorption, digestion, metabolism, and excretion) studies featured drug-likeness. Subsequently, a statistically significant 3D-QSAR model of high correlation coefficient (R2) with 0.822 and cross-validation coefficient (Q2) with 0.6132 at 4 component PLS (partial least square) were used to verify the accuracy of the models. Taxifolin holds good interactions with the binding domain of W80R, highest Glide score of - 9.63 kcal/mol with OH of GLU234 and H bond ASP274 and LEU156 amino acid residues and one pi-cation interaction and one hydrophobic bond with LYS276.

CONCLUSION

Natural compounds have always been a richest source of active compounds with a wide variety of structures, therefore, these compounds showed a special inspiration for medical chemists. The present study has aimed molecular docking and molecular dynamics simulation studies on taxifolin targeting W80R mutant protein of protein kinase B/serine- threonine kinase/AKT1 (EC:2.7.11.1) protein of ovarian cancer for designing therapeutic intervention. The expected result supported the molecular cause in a mutant form which resulted in a gain of ovarian cancer. Here we discussed validations computationally and yet experimental evaluation or in vivo studies are endorsed for further study. Several of these compounds should become the next marvels for early detection of ovarian cancer.

MicroRNAs and Long Noncoding RNAs as Novel Therapeutic Targets in Estrogen Receptor-Positive Breast and Ovarian Cancers

Aromatase inhibitors (AIs) such as anastrozole, letrozole, and exemestane have shown to prevent metastasis and angiogenesis in estrogen receptor (ER)-positive breast and ovarian tumors. They function primarily by reducing estrogen production in ER-positive post-menopausal breast and ovarian cancer patients. Unfortunately, current AI-based therapies often have detrimental side-effects, along with acquired resistance, with increased cancer recurrence. Thus, there is an urgent need to identify novel AIs with fewer side effects and improved therapeutic efficacies. In this regard, we and others have recently suggested noncoding RNAs (ncRNAs), specifically microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), as potential molecular targets for utilization in modulating cancer hallmarks and overcoming drug resistance in several cancers, including ER-positive breast and ovarian cancer. Herein, we describe the disruptive functions of several miRNAs and lncRNAs seen in dysregulated cancer metabolism, with a focus on the gene encoding for aromatase (CYP19A1 gene) and estrogen synthesis as a novel therapeutic approach for treating ER-positive breast and ovarian cancers. Furthermore, we discuss the oncogenic and tumor-suppressive roles of several miRNAs (oncogenic miRNAs: MIR125b, MIR155, MIR221/222, MIR128, MIR2052HG, and MIR224; tumor-suppressive miRNAs: Lethal-7f, MIR27B, MIR378, and MIR98) and an oncogenic lncRNA (MIR2052HG) in aromatase-dependent cancers via transcriptional regulation of the CYP19A1 gene. Additionally, we discuss the potential effects of dysregulated miRNAs and lncRNAs on the regulation of critical oncogenic molecules, such as signal transducer, and activator of transcription 3, β-catenin, and integrins. The overall goal of this review is to stimulate further research in this area and to facilitate the development of ncRNA-based approaches for more efficacious treatments of ER-positive breast and ovarian cancer patients, with a slight emphasis on associated treatment–delivery mechanisms.

Overexpression of Galectin10 Predicts a Better Prognosis in Human Ovarian Cancer

To explore the prognosis of Galectins (LGALS) expression on patients with ovarian cancer, the prognosis of LGALS members in ovarian cancer was retrieved and analyzed by using 'Kaplan-Meier plotter' database. The relation of LGALS to overall survival (OS) was evaluated according to histological subtypes, clinical stages and pathological grade. Quantitative real-time polymerase chain reaction and western blot were used to detect the mRNA and protein expression of LGALS in ovarian cancer and normal ovarian cells. Immunohistochemistry was applied to evaluate the different expression of LGALS between cancer and normal tissues. In total patients with ovarian cancer, LGALS4, LGALS8, LGALS10 and LGALS13 mRNA levels were related to a better OS, and LGALS1 to a worse OS. LGALS1 predicted a worse OS in women with serous, stages III+IV or grade II ovarian cancer. LGALS4 predicted a better OS in patients with endometrioid, stages I+II or grade III ovarian cancer. LGALS10 predicted a longer OS in females with serous, all stages, or grade III cancer. LGALS8 overexpression was related to a better OS in all stages. Notably, mRNA and protein expressions of LGALS4, LGALS10 and LGALS13 were decreased in cancer cells than those in normal cells (P<0.05). Additionally, the immunostaining score of LGALS8, LGALS10 and LGALS13 expression were lower but LGALS1 was higher in caner tissues than those in normal tissues (P<0.001). In conclusion, LGALS10 possibly is a valuable biomarker for predicting a favorable prognosis in patients with ovarian cancer, especially with serous, all stages and grade III cancer.

C-Myc-activated long non-coding RNA PVT1 enhances the proliferation of cervical cancer cells by sponging miR-486-3p

Cervical cancer is one of the most prevalent gynecological malignancies. Although the functions of long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) and c-Myc in tumorigenesis have been acknowledged, the roles of c-Myc and lncRNA-PVT1 in the proliferation of cervical cancer are still unclear. Our study is designed to demonstrate the regulatory network involving c-Myc and lncRNA-PVT1 in cervical cancer. Quantitative real-time PCR and western blot assays were performed in our research to estimate the expression levels of RNA and proteins. CCK8 assays were applied to demonstrate the viability of HeLa and SiHa cells. Immunofluorescence assay was then used to investigate the co-localization of lncRNA-PVT1 and miR-486-3p. Binding of c-Myc to the promoter region of PVT1 was identified by ChIP-assay. Functionally, upregulation of lncRNA-PVT1 enhanced the proliferation and viability of cervical cancer cells. Mechanistically, lncRNA-PVT1 sponged miR-486-3p and released its repression of extracellular matrix protein 1. Besides, c-Myc functioned as an activator of lncRNA-PVT1 and upregulated its expression by binding to the promoter of PVT1 in cervical cancer cells. lncRNA-PVT1 was upregulated by c-Myc and thus enhanced the proliferation of cervical cancer cells by sponging miR-486-3p.

Mutually distinguishing microRNA signatures of breast, ovarian and endometrial cancers in vitro

Early diagnosis and therapy in the first stages of a malignant disease is the most crucial factor for successful cancer treatment and recovery. Currently, there is a high demand for novel diagnostic tools that indicate neoplasms in the first or pre‑malignant stages. MicroRNAs (miRNA or miR) are small non‑coding RNAs that may act as oncogenes and downregulate tumor‑suppressor genes. The detection and mutual discrimination of the three common female malignant neoplasia types breast (BC), ovarian (OC) and endometrial cancer (EC) could be enabled by identification of tumor entity‑specific miRNA expression differences. In the present study, the relative expression levels of 25 BC, EC and OC‑related miRNAs were assessed by reverse transcription‑quantitative PCR and determined using the 2‑ΔΔCq method for normalization against the mean of four housekeeping genes. Expression levels of all miRNAs were analyzed by regression against cell line as a factor. An expression level‑based discrimination between BC and OC cell types was obtained for a subgroup of ten different miRNA types. miR‑30 family genes, as well as three other miRNAs, were found to be uniformly upregulated in OC cells compared with BC cells. BC and EC cells could be distinguished by the expression profiles of six specific miRNAs. In addition, four miRNAs were differentially expressed between EC and OC cells. In conclusion, miRNAs were identified as a potential novel tool to detect and mutually discriminate between BC, OC and EC. Based on a subset of 25 clinically relevant human miRNA types, the present study could significantly discriminate between these three female cancer types by means of their expression levels. For further verification and validation of miRNA‑based biomarker expression signatures that enable valuable tumor detection and characterization in routine screening or potential therapy monitoring, additional and extended in vitro analyses, followed by translational studies utilizing patients' tissue and liquid biopsy materials, are required.

Targeting miRNAs by natural products: A new way for cancer therapy

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression through mRNA degradation or translation inhibition. MiRNAs play important roles in a variety of biological processes, and dysregulation of miRNA expression is highly associated with cancer development. Individual miRNA regulates multiple gene expressions, enabling them to regulate multiple cellular signaling pathways simultaneously. Hence, miRNAs could be served as cancer biomarkers for diagnosis and prognosis, and also therapeutic targets. Recently, more and more evidences showed that natural products such as paclitaxel, curcumin, resveratrol, genistein or epigallocatechin-3-gallate exert their anti-proliferative and/or pro-apoptotic effects through regulating one or more miRNAs, leading to the inhibition of cancer cell growth, induction of apoptosis or enhancement of conventional cancer therapeutic efficacy. Herein, we outlined the recent advances in the regulation of miRNAs expression by the natural products and highlight the importance of these natural drugs as a potential strategy in cancer treatment. This review will help us better understand how natural products modulate miRNAs and contribute to the development of effective and safe natural drugs for therapeutic purposes.

LINC00689 participates in proliferation, chemoresistance and metastasis via miR-31-5p/YAP/β-catenin axis in colorectal cancer

As a kind of high-incidence malignant tumors in the digestive tract, colorectal cancer (CRC) has extremely morbidity and mortality in the population. LncRNAs have been proved to regulate the proliferation, chemoresistance and metastasis of tumors including CRC. LINC00689 and miR-31-5p in CRC were found misregulated in CRC by TCGA analysis. However, the mechanism of LINC00689 and miR-31-5p in regulating CRC remains unknown. The expression levels of LINC00689, miR-31-5p and LATS2 in CRC tissues and cell lines were examined by qRT-PCR assay. Cell proliferation, metastasis (including invasion and migration) were quantified by MTT assay, colony formation and Transwell assay, respectively. Western blotting assay was then performed to verify the levels of YAP/β-catenin and metastasis-related proteins. Dual-luciferase reporter assay and RIP assay were performed to evaluate the interaction between LINC00689 (LATS2) and miR-31-5p. Moreover, the function of LINC00689 and miR-31-5p were confirmed by CRC xenograft in nude mice. LINC00689 was decreased while miR-31-5p was increased in CRC. The overexpression of LINC00689 or the knockdown of miR-31-5p inhibited cell proliferation, chemoresistance and metastasis of CRC cells. Meanwhile, the up-regulated LATS2 suppressed the activity of YAP/β-catenin pathway to repress CRC occurrence. Silencing LATS2 reversed the inhibition effects of overexpression of LINC00689 or knockdown of miR-31-5p on proliferation, chemoresistance and metastasis of CRC cells. LINC00689 indeed acted as a miR-31-5p sponge to inhibit CRC proliferation, chemoresistance and metastasis through up-regulating LATS2 and repressing YAP/β-catenin signaling pathway.

Molecular classification and immunologic characteristics of immunoreactive high‐grade serous ovarian cancer

High‐grade serous ovarian cancer (HGS‐OvCa) is one of the most lethal gynaecological malignancies. Molecular classification identified an immunoreactive subtype of HGS‐OvCa; however, the immunologic characteristics of immunoreactive HGS‐OvcA remain unclear. In this study, 121 immunoreactive HGS‐OvCa samples were identified from a meta‐analysis of 5 large transcriptome profiling data sets using a cross‐platform immunoreactive HGS‐OvCa subgroup‐specific classifier. By comparing the gene expression profiles of immunoreactive HGS‐OvCa samples and normal tissues, 653 differentially expressed genes (DEGs) were identified. KEGG pathway analysis revealed that the leukocyte transendothelial migration pathways were significantly enriched in the immunoreactive HGS‐OvCa. Protein‐protein interaction analysis identified a module that showed strong involvement of the immune‐related chemokine signalling pathway. Moreover, the GSEA enrichment analysis showed a T‐cell subgroup and M1 macrophages were significantly enriched in immunoreactive OvCa compared with normal samples. Macrophage infiltration levels were significantly elevated in immunoreactive HGS‐OvCa compared with other OvCa subtypes. In addition, expression of immune checkpoint molecules VTCN1 and IDO1 was significantly increased in immunoreactive HGS‐OvCa. In summary, our results suggest that the immunoreactive HGS‐OvCa has unique molecular characteristics and a tumour‐associated immune microenvironment featured by increased infiltration of macrophages, rather than lymphocytes. VTCN1 could be potential targets for the treatment of immunoreactive HGS‐OvCa.

The overexpression of lncRNA MEG3 inhibits cell viability and invasion and promotes apoptosis in ovarian cancer by sponging miR-205-5p

PURPOSE

Ovarian cancer is a common and fatal cancer in women. The long non-coding RNA (lncRNA) MEG3 was reported to affect the cellular processes of ovarian cancer, but the mechanisms remain unclear. Here, we aimed to explore the potential regulatory mechanism of MEG3 in ovarian cancer.

MATERIALS AND METHODS

A reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was conducted to analyze the expression levels of MEG3 and miR-205-5p in tissues and cell lines. An MTT assay was utilized to determine the cell viability of ovarian cancer SKOV-3 and OVCAR-8 cells. A flow cytometry analysis was employed to disclose the ovarian cancer cell apoptosis. The migration and invasion of SKOV-3 and OVCAR-8 cells were examined using a Transwell assay. A bioinformatics analysis indicated miR-205-5p as a direct target of MEG3, and a luciferase reporter assay was conducted to validate the interaction between MEG3 and miR-205-5p.

RESULTS

MEG3 was significantly down-regulated, while miR-205-5p was up-regulated in ovarian cancer tissues and cell lines. The overexpression of MEG3 and the knockdown of miR-205-5p inhibited cell viability, migration and invasion but promoted the apoptosis rate in ovarian cancer cells. MiR-205-5p was identified as a downstream gene of MEG3 and is negatively regulated by MEG3. The introduction of miR-205-5p reversed the up-regulation of MEG3-mediated suppression effects on cell viability, migration and invasion and increased cell apoptosis in ovarian cancer cells.

CONCLUSION

The overexpression of lncRNA MEG3 inhibits cell proliferation and cell invasion and promotes apoptosis in ovarian cancer by sponging miR-205-5p.

Modulating Macrophage Phenotype by Sustained MicroRNA Delivery Improves Host-Implant Integration

Biomedical implant failure due to the host's response remains a challenging problem. In particular, the formation of the fibrous capsule is a common barrier for the normal function of implants. Currently, there is mounting evidence indicating that the polarization state of macrophages plays an important role in effecting the foreign body reaction (FBR). This opens up a potential avenue for improving host-implant integration. Here, electrospun poly(caprolactone-co-ethyl ethylene phosphate) nanofiber scaffolds are utilized to deliver microRNAs (miRs) to induce macrophage polarization and modulate FBR. Specifically, C57BL/6 mice that are treated with M2-inducing miRs, Let-7c and miR-124, display relatively thinner fibrous capsule formation around the scaffolds at both Week 2 and 4, as compared to treatment with M1-inducing miR, Anti-Let-7c. Histological analysis shows that the density of blood vessels in the scaffolds are the highest in miR-124 treatment group, followed by Anti-Let-7c and Let-7c treatment groups. Based on immunohistochemical quantifications, these miR-encapsulated nanofiber scaffolds are useful for localized and sustained delivery of functional miRs and are able to modulate macrophage polarization during the first 2 weeks of implantation to result in significant alteration in host-implant integration at longer time points.

Role of microRNAs as Clinical Cancer Biomarkers for Ovarian Cancer: A Short Overview

Ovarian cancer has the highest mortality rate among gynecological cancers. Early clinical signs are missing and there is an urgent need to establish early diagnosis biomarkers. MicroRNAs are promising biomarkers in this respect. In this paper, we review the most recent advances regarding the alterations of microRNAs in ovarian cancer. We have briefly described the contribution of miRNAs in the mechanisms of ovarian cancer invasion, metastasis, and chemotherapy sensitivity. We have also summarized the alterations underwent by microRNAs in solid ovarian tumors, in animal models for ovarian cancer, and in various ovarian cancer cell lines as compared to previous reviews that were only focused the circulating microRNAs as biomarkers. In this context, we consider that the biomarker screening should not be limited to circulating microRNAs per se, but rather to the simultaneous detection of the same microRNA alteration in solid tumors, in order to understand the differences between the detection of nucleic acids in early vs. late stages of cancer. Moreover, in vitro and in vivo models should also validate these microRNAs, which could be very helpful as preclinical testing platforms for pharmacological and/or molecular genetic approaches targeting microRNAs. The enormous quantity of data produced by preclinical and clinical studies regarding the role of microRNAs that act synergistically in tumorigenesis mechanisms that are associated with ovarian cancer subtypes, should be gathered, integrated, and compared by adequate methods, including molecular clustering. In this respect, molecular clustering analysis should contribute to the discovery of best biomarkers-based microRNAs assays that will enable rapid, efficient, and cost-effective detection of ovarian cancer in early stages. In conclusion, identifying the appropriate microRNAs as clinical biomarkers in ovarian cancer might improve the life quality of patients.

MiR-200c sensitizes Olaparib-resistant ovarian cancer cells by targeting Neuropilin 1

BACKGROUND

Ovarian cancer (OC) is the most lethal gynecological malignancy and the second leading cause of cancer-related death in women. Treatment with PARP inhibitors (PARPi), such as Olaparib, has been recently introduced for OC patients, but resistance may occur and underlying mechanisms are still poorly understood. The aim of this study is to identify target genes within the tumor cells that might cause resistance to Olaparib. We focused on Neuropilin 1 (NRP1), a transmembrane receptor expressed in OC and correlated with poor survival, which has been also proposed as a key molecule in OC multidrug resistance.

METHODS

Using three OC cell lines (UWB, UWB-BRCA and SKOV3) as model systems, we evaluated the biological and molecular effects of Olaparib on OC cell growth, cell cycle, DNA damage and apoptosis/autophagy induction, through MTT and colony forming assays, flow cytometry, immunofluorescence and Western blot analyses. We evaluated NRP1 expression in OC specimens and cell lines by Western blot and qRT-PCR, and used RNA interference to selectively inhibit NRP1. To identify miR-200c as a regulator of NRP1, we used miRNA target prediction algorithms and Pearsons' correlation analysis in biopsies from OC patients. Then, we used a stable transfection approach to overexpress miR-200c in Olaparib-resistant cells.

RESULTS

We observed that NRP1 is expressed at high levels in resistant cells (SKOV3) and is upmodulated in partially sensitive cells (UWB-BRCA) upon prolonged Olaparib treatment, leading to poor drug response. Our results show that the selective inhibition of NRP1 is able to overcome Olaparib resistance in SKOV3 cells. Moreover, we demonstrated that miR-200c can target NRP1 in OC cells, causing its downmodulation, and that miR-200c overexpression is a valid approach to restore Olaparib sensitivity in OC resistant cells.

CONCLUSIONS

These data demonstrate that miR-200c significantly enhanced the anti-cancer efficacy of Olaparib in drug-resistant OC cells. Thus, the combination of Olaparib with miRNA-based therapy may represent a promising treatment for drug resistant OC, and our data may help in designing novel precision medicine trials for optimizing the clinical use of PARPi.

MicroRNAs in ovarian cancer and recent advances in the development of microRNA-based biosensors

Ovarian cancer is the most aggressive of all gynaecological malignancies and is the leading cause of cancer-associated mortality worldwide.

Overexpression of the lncRNA FER1L4 inhibits paclitaxel tolerance of ovarian cancer cells via the regulation of the MAPK signaling pathway

To determine how the lncRNA FER1L4 in ovarian cancer cells influences paclitaxel (PTX) resistance, we examined the expression level of FER1L4 in human ovarian epithelial cell lines IOSE80 and HOSEpiC and human ovarian cancer cell lines OVCAR-3, Caov-3, and SKOV3 through RNA isolation and quantitative polymerase chain reaction (qRT-PCR). SKOV3 cell lines were treated with PTX. The cell survival rate and apoptosis rate of SKOV3 and SKOV3-PR at different PTX dose levels were evaluated. Next, qRT-PCR was performed to detect the expression of FER1L4 in SKOV3 and SKOV3-PR cell lines. SKOV3-PR cell lines were transfected with pcDNA3.1 as the control group (SKOV3-PR/pcDNA3.1) or pcDNA3.1-FER1L4 to upregulate the expression level of FER1L4 (SKOV3-PR/pcDNA3.1-FER1L4). The level of cell survival, apoptosis, and colony formation were compared between the two groups using MTT, flow cytometry analysis, and colony formation assay. To reveal the molecular mechanism, we measured the relative protein phosphorylation level of ERK and MAPK in SKOV3, SKOV3-PR, SKOV3-PR/pcDNA3.1, and SKOV3-PR/pcDNA3.1-FER1L4 groups using an enzyme-linked immunosorbent assay. The effects of SB203580 (a p38 MAPK inhibitor) on PTX were also investigated to reveal the function of the MAPK pathway on the PTX tolerance of SKOV3. In comparison with normal ovarian epithelial cells, FER1L4 was downregulated. The FER1L4 level was decreased in human ovarian cancer cells with drug resistance than in common ovarian cancer cells. The upregulation of FER1L4 could promote the PTX sensitivity of ovarian cancer cells. The increased level of FER1L4 could suppress the PTX resistance of ovarian cancer cells through the inhibition of the MAPK signaling pathway.

MiR-214 sensitizes human colon cancer cells to 5-FU by targeting Hsp27

Overcoming chemorestistance to 5-fluorouracil (5-FU) could offer a new treatment option for highly malignant colon cancer. In our study, differential microRNA expression profiling revealed that miR-214 is downregulated in 5-FU-resistant colon cancer cells compared to normal cells. In vitro, miR-214 could sensitize non-resistant colon cancer cells and 5-FU-resistant colon cancer cellsto 5-FU. Functionally, miR-214 inhibited cell clone formation and cell growth and enhanced 5-FU-inducing cell apoptosis and caspase-3 levels. MiR-214 targeted heat shock protein 27 (Hsp27), as confirmed via dual luciferase reporter assays and western blots. Hsp27 also sensitized HT-29 and LoVo to 5-FU by enhancing cell apoptosis. Overexpression of Hsp27 could block miR-214 with an effect on the sensitivity of colon cancer cells to 5-FU. In conclusion, miR-214 sensitizes colon cancer cells to 5-FU by targeting Hsp27, indicating a significant role for this miRNA in colon cancer chemotherapy.

MUL1 E3 ligase regulates the antitumor effects of metformin in chemoresistant ovarian cancer cells via AKT degradation

Chemoresistance is one of most critical clinical problems encountered when treating patients with ovarian cancer, due to the fact that the disease is usually diagnosed at advanced stages. Metformin is used as a first‑line drug for the treatment of type 2 diabetes; however, drug repositioning studies have revealed its antitumor effects, mainly mediated through AMP‑activated protein kinase (AMPK) activation and AKT/mammalian target of rapamycin (mTOR) pathway inhibition in various types of cancer, including drug‑resistant cancer cells. The current study revealed that the novel antitumor mechanism of metformin is mediated by regulation of mitochondrial E3 ubiquitin protein ligase 1 (MUL1) expression that negatively regulates AKT. The results demonstrated that metformin decreased the expression of AKT protein levels via MUL1 E3 ligase. In addition, metformin increased both mRNA and protein levels of MUL1 and promoted degradation of AKT in a proteasome‑dependent manner. Silencing MUL1 expression suppressed the metformin‑mediated AKT degradation and its downstream effects. Cell cycle analysis and a clonogenic assay demonstrated that knockdown of MUL1 significantly diminished the antitumor effects of metformin. Together, these data indicate that MUL1 regulates metformin‑mediated AKT degradation and the antitumor effects of metformin in chemoresistant ovarian cancer cell lines.

miR-137 mediates the functional link between c-Myc and EZH2 that regulates cisplatin resistance in ovarian cancer

Platinum drugs are used in first-line to treat ovarian cancer, but most of the patients eventually generate resistance after treatment with these drugs. Although both c-Myc and EZH2 have been implicated in regulating cisplatin resistance in ovarian cancer, the interplay between these two regulators is poorly understood. Using RNA sequence analysis (RNA-seq), for the first time we find that miR-137 level is extremely low in cisplatin resistant ovarian cancer cells, correlating with higher levels of c-Myc and EZH2 expression. Further analyses indicate that in resistant cells c-Myc enhances the expression of EZH2 by directly suppressing miR-137 that targets EZH2 mRNA, and increased expression of EZH2 activates cellular survival pathways, resulting in the resistance to cisplatin. Inhibition of c-Myc-miR-137-EZH2 pathway re-sensitizes resistant cells to cisplatin. Both in vivo and in vitro analyses indicate that cisplatin treatment activates c-Myc-miR-137-EZH2 pathway. Importantly, elevated c-Myc-miR-137-EZH2 pathway in resistant cells is sustained by dual oxidase maturation factor 1 (DUOXA1)-mediated production of reactive oxygen species (ROS). Significantly, clinical studies further confirm the activated c-Myc-miR-137-EZH2 pathway in platinum drug-resistant or recurrent ovarian cancer patients. Thus, our studies elucidate a novel role of miR-137 in regulating c-Myc-EZH2 axis that is crucial to the regulation of cisplatin resistance in ovarian cancer.

Identification of core genes in ovarian cancer by an integrative meta-analysis

BACKGROUND

Epithelial ovarian cancer is one of the most severe public health threats in women. Since it is still challenging to screen in early stages, identification of core genes that play an essential role in epithelial ovarian cancer initiation and progression is of vital importance.

RESULTS

Seven gene expression datasets (GSE6008, GSE18520, GSE26712, GSE27651, GSE29450, GSE36668, and GSE52037) containing 396 ovarian cancer samples and 54 healthy control samples were analyzed to identify the significant differentially expressed genes (DEGs). We identified 563 DEGs, including 245 upregulated and 318 downregulated genes. Enrichment analysis based on the gene ontology (GO) functions and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways showed that the upregulated genes were significantly enriched in cell division, cell cycle, tight junction, and oocyte meiosis, while the downregulated genes were associated with response to endogenous stimuli, complement and coagulation cascades, the cGMP-PKG signaling pathway, and serotonergic synapse. Two significant modules were identified from a protein-protein interaction network by using the Molecular Complex Detection (MCODE) software. Moreover, 12 hub genes with degree centrality more than 29 were selected from the protein-protein interaction network, and module analysis illustrated that these 12 hub genes belong to module 1. Furthermore, Kaplan-Meier analysis for overall survival indicated that 9 of these hub genes was correlated with poor prognosis of epithelial ovarian cancer patients.

CONCLUSION

The present study systematically validates the results of previous studies and fills the gap regarding a large-scale meta-analysis in the field of epithelial ovarian cancer. Furthermore, hub genes that could be used as a novel biomarkers to facilitate early diagnosis and therapeutic approaches are evaluated, providing compelling evidence for future genomic-based individualized treatment of epithelial ovarian cancer.

MicroRNA signatures discriminate between uterine and ovarian serous carcinomas

Synchronous endometrial and ovarian malignancies occur in 5% of women presenting with endometrial cancer and 10% of patients presenting with ovarian malignancy. When a high-grade serous carcinoma concurrently involves both ovary and endometrium, pathological determination of whether they are synchronous primaries or metastatic tumors from one primary site can be challenging. MicroRNAs (miRNA) are 22-nucleotide noncoding RNAs that are aberrantly expressed in cancer cells and may inherit their cellular lineage characteristics. We explored possible differential miRNA signatures that may separate high-grade ovarian serous carcinoma from primary endometrial serous carcinoma. Forty-seven samples of histologically pure high-grade serous carcinoma of both uterine (16 case) and ovarian primaries (31 cases) were included. Expression of 384 mature miRNAs was analyzed using ABI TaqMan Low-Density Arrays technology. A random forest model was used to identify miRNAs that together could differentiate between uterine and ovarian serous carcinomas. Among 150 miRNAs detectable at various levels in the study cases, a panel of 11-miRNA signatures was identified to significantly discriminate between ovarian and uterine serous carcinoma (P < .05). A nested cross-validated convergent forest plot using 6 of the 11 miRNA signature was eventually established to classify the tumors with 91.5% accuracy. In conclusion, we have characterized a miRNA signature panel in this exploratory study that shows significant discriminatory power in separating primary ovarian high-grade serous carcinoma from its endometrial counterpart.

Sperm associated antigen 9 (SPAG9) a promising therapeutic target of ovarian carcinoma

SPAG9 is a novel tumor associated antigen, expressed in variety of malignancies. However, its role in ovarian cancer remains unexplored. SPAG9 expression was validated in ovarian cancer cells by real time PCR and Western blot. SPAG9 involvement in cell cycle, DNA damage, apoptosis, paclitaxel sensitivity and epithelial- mesenchymal transition (EMT) was investigated employing RNA interference approach. Combinatorial effect of SPAG9 ablation and paclitaxel treatment was evaluated in in vitro. Quantitative PCR and Western blot analysis revealed SPAG9 expression in A10, SKOV-3 and Caov3 compared to normal ovarian epithelial cells. SPAG9 ablation resulted in reduced cellular proliferation, colony forming ability and enhanced cytotoxicity of chemotherapeutic agent paclitaxel. Effect of ablation of SPAG9 on cell cycle revealed S phase arrest and showed decreased expression of CDK1, CDK2, CDK4, CDK6, cyclin B1, cyclin D1, cyclin E and increased expression of tumor suppressor p21. Ablation of SPAG9 also resulted in increased apoptosis with increased expression of various pro- apoptotic molecules including BAD, BID, PUMA, caspase 3, caspase 7, caspase 8 and cytochrome C. Decreased expression of mesenchymal markers and increased expression of epithelial markers was found in SPAG9 ablated cells. Combinatorial effect of SPAG9 ablation and paclitaxel treatment was evaluated in in vitro assays which showed that ablation of SPAG9 resulted in increased paclitaxel sensitivity and caused enhanced cell death. In vivo ovarian cancer xenograft studies showed that ablation of SPAG9 resulted in significant reduction in tumor growth. Present study revealed therapeutic potential of SPAG9 in ovarian cancer.

Circulating miR-31 as an effective biomarker for detection and prognosis of human cancer: a meta-analysis

PURPOSE

Circulating miR-31 was found to be associated with cancers detection and prognosis. The present meta-analysis aimed to explore the effect of circulating miR-31 on cancer detection and prognosis.

METHOD

The studies were accessed using multiple databases. RevMan5.3, Meta-DiSc 1.4, and STATA14.0 were used to estimate the pooled effects, heterogeneity among studies, and publication bias.

RESULTS

A total of 14 studies with 1397 cancer patients and 1039 controls were included. For the 12 prognostic tests, the adjusted pooled-AUC was 0.79 (95% CI: 0.73-0.86) as the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odd ratio (DOR) from 10 tests was 0.79 (95% CI: 0.76-0.82), 0.79 (95% CI: 0.76-0.82), 3.81 (95% CI: 2.90-5.01), 0.26 (95% CI: 0.20-0.35), and 16.81 (95% CI: 9.67-29.25), respectively. For the 5 prognosis analyses, the pooled HR (hazard ratio) of overall survival (OS) was 1.55 (95% CI 1.30-1.86) for high versus low circulating miR-31 expression. However, high expression of circulating miR-31 did not significantly increase the risk of poor differentiation (pooled OR=1.39, 95% CI: 0.56-3.47) and LNM (pooled OR=3.46, 95% CI: 0.96-12.42) in lung cancer.

CONCLUSION

Circulating miR-31 is an effective biomarker and could be used as a component of miRs signature for cancer detection and prognosis surveillance.

Dysregulation of miRNAs in bladder cancer: altered expression with aberrant biogenesis procedure

Aberrant expression profiles of miRNAs are widely observed in the clinical tissue specimens and urine samples as well as the blood samples of bladder cancer patients. These profiles are closely related to the pathological features of bladder cancer, such as the tumour stage/grade, metastasis, recurrence and chemo-sensitivity. MiRNA biogenesis forms the basis of miRNA expression and function, and its dysregulation has been shown to be essential for variations in miRNA expression profiles as well as tumourigenesis and cancer progression. In this review, we summarize the up-to-date and widely reported miRNAs in bladder cancer that display significantly altered expression. We then compare the miRNA expression profiles among three different sample types (tissue, urine and blood) from patients with bladder cancer. Moreover, for the first time, we outline the dysregulated miRNA biogenesis network in bladder cancer from different levels and analyse its possible relationship with aberrant miRNA expression and the pathological characteristics of the disease.

Biological Function of Ribosomal Protein L10 on Cell Behavior in Human Epithelial Ovarian Cancer

Ribosomal protein L10 (RPL10) is one of large ribosomal proteins and plays a role in Wilms' tumor and premature ovarian failure. However, the function of RPL10 in human epithelial ovarian cancer (EOC) remains unknown. The purpose of this study was to examine the expression level and function of RPL10 in EOC. RPL10 protein expression was detected by immunohistochemistry and Western blot. The association RPL10 expression with clinical features was analyzed. Loss-of-function and gain-of-function approaches were applied in cellular assays, including cell viability, migration, invasion, and apoptosis. Our study demonstrated for the first time that RPL10 was upregulated in human EOC compared with normal ovarian tissues. Knockdown of RPL10 inhibited cell viability, migration, and invasion, and increased cell apoptosis. On the contrary, upregulation of RPL10 increased cell viability, migration, invasion, and decreased cell apoptosis. Furthermore, miR-143-3p regulated RPL10 expression. Our data indicate that RPL10 is a potential tissue biomarker of patients with EOC and may be a therapeutic target of ovarian cancer.

Upregulation of microRNA-4417 and Its Target Genes Contribute to Nickel Chloride-promoted Lung Epithelial Cell Fibrogenesis and Tumorigenesis

Nickel compounds have been classified as carcinogens and shown to be associated with induction of epithelial-mesenchymal transition (EMT) in fibrogenesis and tumorigenesis, as well as the crucial role of microRNAs (miRNAs) and their related genes in controlling EMT and cancer metastasis. Thus, the mechanisms involved in the regulation of EMT in nickel-treated cells are of potential interest in understanding lung fibrosis and tumor progression. We investigated the miRNA-dependent mechanisms involved in nickel-induced EMT in lung epithelial cells. Nickel increased miR-4417 expression and decreased its target gene TAB2 expression. Treatment of cells with TGF-β inhibitor SB525334 significantly blocked NiCl2 and TGF-β-induced EMT. The expression of miR-4417 was abolished by SB525334 in TGF-β-treated cells, but not in nickel-treated cells. Both overexpression of miR-4417 and silencing of TAB2 induced fibronectin expression, but did not reduce E-cadherin expression. Moreover, oral administration of nickel promoted lung tumor growth in nude mice that had received BEAS-2B transformed cells by intravenous injection. The induction of EMT by nickel is mediated through multiple pathways. Induction of abundant miR-4417 and reduction of TAB2 expression following nickel exposure and may be involved in nickel-induced fibronectin. These findings provide novel insight into the roles of nickel in fibrogenesis and tumor progression.

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.

miR-214 promotes radioresistance in human ovarian cancer cells by targeting PETN

Ovarian cancer is one of the leading causes of death among gynecological malignancies. Increasing evidence indicate that dysregulation of microRNAs (miRNAs) plays an important role in tumor radioresistance. The aim of the present study is to investigate whether microRNA-214 (miR-214) was involved in radioresistance of human ovarian cancer. Here, we showed that miR-214 was significantly up-regulated in ovarian cancer tissues and radioresistance ovarian cancer cell lines. Transfection of miR-214 agomir in radiosensitive ovarian cancer cell lines promoted them for resistance to ionizing radiation, whereas transfection of miR-214 antagomir in radioresistance ovarian cancer cell lines sensitized them to ionizing radiation again. Furthermore, we found miR-214 effectively promoted tumor radioresistance in xenograft animal experiment. Western blotting and quantitative real-time PCR demonstrated that miR-214 negatively regulated PTEN in radioresistance ovarian cancer cell lines and ovarian cancer tissues. Taken together, our data conclude that miR-214 contributes to radioresistance of ovarian cancer by directly targeting PTEN.

MiR-31 and miR-128 regulates poliovirus receptor-related 4 mediated measles virus infectivity in tumors

Oncolytic measles virus strains are currently being evaluated in several clinical trials, as a promising novel oncolytic platform. Poliovirus receptor-related 4 (PVRL4) was recently identified as a potent measles virus (MV) receptor; however, its regulation is not yet understood. Increased levels of PVRL4 protein were observed in cell membrane, cytoplasm and nuclei of glioblastoma, breast and ovarian tumor clinical samples with no significant change in PVRL4 mRNA levels in glioblastoma and breast cancer compared with their corresponding control samples, suggesting that PVRL4 is likely post-transcriptionally regulated. Therefore, we sought to investigate the potential role of miRNAs in PVRL4 regulation and thus MV infectivity. We demonstrated that miR-31 and miR-128 can bind to the 3'UTR of PVRL4 and decrease PVRL4 levels while anti-miR-31/128 increase PVRL4 levels suggesting that PVRL4 is miRNA targeted. Furthermore, miR-31/128 expression levels were down-regulated in glioblastoma and breast tumor samples and showed significant negative correlations with PVRL4 levels. Infection with an MV strain that exclusively utilizes PVRL4 as its receptor showed that over-expression of miR-31/128 decreases MV infectivity while inhibition of the respective miRNAs via anti-miRs increase MV infectivity and reduce tumor size in mouse xenograft models of glioblastoma, breast and ovarian cancer. Additionally, miR-128 levels showed significant correlations with MV infection and in vivo anti-tumor effect, while MV infection increased miR-31 expression and thereby contributed to the observed decrease in PVRL4 levels. This study suggests that PVRL4 is post-transcriptionally regulated by miR-128 and miR-31 and harbors possible miRNA targets that could modulate MV infectivity and in turn enhance MV based oncolytic therapeutic strategies.

Reprogramming macrophage orientation by microRNA 146b targeting transcription factor IRF5

The regulation of macrophage orientation pathological conditions is important but still incompletely understood. Here, we show that IL-10 and Rag1 double knockout mice spontaneously develop colitis with dominant M1 macrophage phenotype, suggesting that IL-10 regulates macrophage orientation in inflammation. We demonstrate that IL-10 stimulation induced miR-146b expression, and that the expression of miR-146b was impaired in IL-10 deficient macrophages. Our data show that miR-146b targets IRF5, resulting in the regulation of macrophage activation. Furthermore, miR-146b deficient mice developed intestinal inflammation with enhanced M1 macrophage polarization. Finally, miR-146b mimic treatment significantly suppresses M1 macrophage activation and ameliorates colitis development in vivo. Collectively, the results suggest that IL-10 dependent miR-146b plays an important role in the modulation of M1 macrophage orientation.

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Interleukin 10-induced miR-146b plays a critical role in the regulation of macrophage polarization and colitis development by targeting IRF5.

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Treatment with miR-146b mimic significantly suppresses M1 macrophage activation and ameliorates colitis development.

Interleukin 10 and Interleukin receptor are clearly involved in the development of inflammatory bowel diseases and other inflammatory diseases. Notably, the mutation of Interleukin 10 and Interleukin 10 receptor are clearly correlated with inflammatory bowel diseases. In the present study we show that Interleukin 10-induced miR-146b plays a critical role in the regulation of macrophage polarization and colitis development by targeting IRF5. Treatment with miR-146b mimic significantly suppresses M1 macrophage activation and ameliorates colitis development. The results highlight the potent role of miR146b in the control of immune responses and pathogenesis of inflammatory diseases.

The future therapy of endometrial cancer: microRNA's functionality, capability, and putative clinical application

PURPOSE

Endometrial cancer (EC) therapy is characterized by the heterogeneity of EC subtypes resulting in unclear clinical behavior as well as in unsatisfactory treatment options. The available biomarkers, such as cellular tumor antigen p53 (TP53), phosphatidylinositol 3,4,5-trisphosphate 3-phosphatase and dual-specificity protein phosphatase (PTEN), and phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) genes alone might not be sufficient, and thus, new predictive and prognostic biomarkers are urgently required. The biomolecule class of microRNA represents a group of endogenously expressed regulatory factors primarily involved in control of pivotal cancer-related mechanisms including cell cycle, proliferation, apoptosis, and metastasis. Here, we review the current state of science regarding microRNA functionality in EC progression.

Expression of microRNA-30a-5p in drug-resistant and drug-sensitive ovarian cancer cell lines

The present study aimed to explore the expression of microRNA (miRNA or miR) in drug-resistant and drug-sensitive ovarian cancer cell lines, and to seek the potential therapeutic target of ovarian cancer drug-resistant mechanism in order to improve drug resistance by altering miRNA levels. The drug-resistant characteristics of SKOV3/DDP, SKOV3, COC1/DDP and COC1 cell lines were studied. The miRNAs that were differentially expressed between cisplatin-resistant cells and its parental cells in ovarian cancer were screened with a miRNA chip. The effect of miRNAs was detected, and their drug-resistant mechanism was investigated by transfection and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide methods. Among the expression screening of miRNAs, 41 mRNAs, including Homo sapiens (hsa)-miR-30a-5p and hsa-miR-34c-5p, were highly expressed in the drug-resistant cells, whereas 44 miRNAs, including hsa-miR-96-5p and hsa-miR-200c-3p, were lowly expressed. The expression levels of hsa-miR-30a-5p in two types of ovarian cancer chemotherapy-resistant cell lines were significantly higher than those in chemotherapy-sensitive cell lines, which was associated with ovarian cancer chemotherapy resistance. In conclusion, high expression of miRNA-30a-5p was able to promote cell growth and colony forming ability, and enhance cell migration and invasion. Thus, miRNA-30a-5p is expected to become a meaningful novel target for ovarian cancer resistant treatment.

Molecular bases of aberrant miR-182 expression in ovarian cancer

The molecular bases of miR-182 deregulation in epithelial ovarian cancers (EOCs) remain unknown and its diagnostic or prognostic role in EOCs is still unclear. We performed miR-182 expression analysis using a microarray approach and real-time PCR (qPCR). We also used array comparative genomic hybridization and methylated DNA immunoprecipitation to study copy number changes and methylation aberrations within coding locus/promoter sequences of miR-182 in EOC tissues, respectively. We have found that miR-182 expression is significantly increased in EOC (P < 0.00001) and that higher miR-182 expression in EOC is linked with significantly shorter overall survival (P = 0.026). The methylation of miR-182 promoter was significantly associated with lower miR-182 expression in EOC tissues (P = 0.045). miR-182 over-expression is connected with copy number (CN) gains of this miRNA coding sequences in EOC (P = 0.002), and the number of PRDM5 copies is significantly and inversely correlated with miR-182 expression evaluated by qPCR (R = -0.615, P = 0.009). We conclude that the aberrant miR-182 expression in EOC may be due to CN gains within its coding locus. The miR-182 promoter is rarely methylated in EOC, and its methylation status is associated with lower miR-182 expression. Deletion of the PRDM5 locus may play a supportive role in miR-182 overexpression in EOC. miR-182 is an unfavorable prognostic factor in EOC. © 2016 Wiley Periodicals, Inc.

MiR-486-3p targeting ECM1 represses cell proliferation and metastasis in cervical cancer

MicroRNAs (miRNAs) regulate gene expression and are involved in cervical cancer. But the molecular mechanism is still unclear. Here, miRNA profile of cervical cancer was performed and demonstrated that miR-486-3p decreased in specimens of cervical cancer patients. In addition, our clinical data show that decreased miR-486-3p was associated with metastasis in cervical cancer patients. ECM1 was predicted and velified as a target gene of miR-486-3p. Overexpression of miR-486-3p inhibited cell growth and metastasis by targeting ECM1. In a conclusion, these findings suggest that miR-486-3p is a tumor suppressor miRNA and induction of miR-486-3p is a potential strategy to inhibit cervical cancer progression.

Diagnostic and therapeutic biomarkers in pancreaticobiliary malignancy

Pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CCA) are two malignancies that carry significant morbidity and mortality. The poor prognoses of these cancers are strongly related to lack of effective screening modalities as well as few therapeutic options. In this review, we highlight novel biomarkers that have the potential to be used as diagnostic, prognostic and predictive markers. The focus of this review is biomarkers that can be evaluated on endoscopically-obtained biopsies or brush specimens in the pre-operative setting. We also provide an overview of novel serum based markers in the early diagnosis of both PDAC and CCA. In pancreatic cancer, the emphasis is placed on prognostic and theranostic markers, whereas in CCA the utility of molecular markers in diagnosis and prognosis are highlighted.

MicroRNAs: New players in endometriosis

Endometriosis is an estrogen-dependent inflammatory disorder that limits the quality of life of affected women. This pathology affects 10% of reproductive-age women, although the prevalence in those patients experiencing pain, infertility or both is as high as 35%-50%. Endometriosis is characterized by endometrial-like tissue outside the uterus, primarily on the pelvic peritoneum, ovaries and the pouch of Douglas. Despite extensive research endeavours, a unifying theory regarding the exact etiopathogenic mechanism of this high prevalent and incapacitating condition is still lacking, although it has been suggested that epigenetics could be involved. MicroRNAs (miRNAs), one of the epigenetic players, are small non-coding RNAs that can act as post-transcriptional regulators of gene expression, reducing the expression of their target mRNAs either inhibiting its translation or promoting its degradation. MiRNA expression profiles are specific of tissue and cell type. Abnormal miRNA expression has been described in different pathological conditions, such as a myriad of oncological, cardiovascular and inflammatory diseases and gynecological pathologies. In endometriosis, miRNA expression patterns of eutopic endometrium from patients and control women and from different endometriotic lesions have been described. These small non-coding molecules have become attractive candidates as novel biomarkers for an early non-invasive diagnosis of the disease, which could suppose a valuable benefit to the patients in terms of improvement of prognosis and reduction of the ratio of recurrence. In this systematic review we will focus on the role of miRNAs in the pathophisiology of endometriosis.

Fascin1 in carcinomas: Its regulation and prognostic value

Previous cell biological studies demonstrate that the actin bundling protein fascin1 regulates cell motility, migration and invasion. Human studies demonstrate that fascin1 is upregulated in many epithelial cancers. This review gives a brief overview of the role of fascin1 in cell migration and invasion, but focuses mainly on the regulation and clinical relevance of fascin1 in epithelial cancers. Here, we propose fascin1 as a potent prognostic biomarker for breast, colorectal, esophageal cancers and head and neck squamous cell carcinomas. Fascin1 may also be an attractive drug target against these carcinomas in the future, but more studies are needed.

Profile of differentially expressed miRNAs in high-grade serous carcinoma and clear cell ovarian carcinoma, and the expression of miR-510 in ovarian carcinoma

Improved insight into the molecular and genetic profile of different types of epithelial ovarian cancer (EOC) is required for understanding the carcinogenesis of EOC and may potentially be exploited by future targeted therapies. The aim of the present study was to identify a unique microRNA (miRNA) patterns and key miRNAs, which may assist in predicting progression and prognosis in high‑grade serous carcinoma (HGSC) and clear cell carcinoma (CCC). To identify unique miRNA patterns associated with HGSC and CCC, a miRNA microarray was performed using Chinese tumor bank specimens of patients with HGSC or CCC in a retrospective analysis. The expression levels of four deregulated miRNAs were further validated using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) in an external cohort of 42 cases of HGSC and 36 cases of CCC. Kaplan‑Meier analysis was performed to analyze the correlation between the expression levels of the four miRNAs and patient prognosis. Among these validated miRNAs, miR‑510 was further examined in another cohort of normal ovarian tissues, as well as the HGSC, low‑grade serous carcinoma (LGSC) and CCC specimens using RT‑qPCR and in situ hybridization. The results revealed that, of the 768 miRNAs analyzed in the microarray, 33 and 50 miRNAs were significantly upregulated and downregulated, respectively, with at least a 2‑fold difference in HGSC, compared with CCC. The quantitative analysis demonstrated that miR‑510 and miR‑129‑3p were significantly downregulated, and that miR‑483‑5p and miR‑miR‑449a were significantly upregulated in CCC, compared with HGSC (P<0.05), which was consistent with the microarray results. Kaplan‑Meier analysis revealed low expression levels of miR‑510 and low expression levels of miR‑129‑3p, advanced International Federation of Gynecology and Obstetrics (FIGO) stage, lymphatic metastasis and that HGSC was significantly associated with the poorer overall survival rates (P<0.05). The expression of miR‑510 was significantly higher in the LGSC and CCC tissues, compared with the HGSC and normal ovarian tissues. The results of the present study suggested that different subtypes of EOC have specific miRNA signatures, and that miR‑510 may be involved differently in HGSC and CCC. Thus, miR‑510 and miR‑129‑3p may be considered as potential novel candidate clinical biomarkers for predicting the outcome of EOC.

MicroRNA in Ovarian Biology and Disease

MicroRNAs (miRNAs) are posttranscriptional gene regulatory molecules that show regulated expression within ovarian tissue. Most research investigating miRNAs in the ovary has relied exclusively on in vitro analyses. In this review, we highlight those few studies in which investigators have illustrated an in vivo effect of miRNAs on ovarian function. We also provide a synopsis of how these small noncoding RNAs can impact ovarian disease. miRNAs have great potential as novel diagnostic biomarkers for the detection of ovarian disease and in the assisted reproductive technologies (ART) for selection of healthy viable oocytes and embryos.

EIF2C, Dicer, and Drosha are up-regulated along tumor progression and associated with poor prognosis in bladder carcinoma

EIF2C, Dicer, and Drosha are microRNA-regulating machinery components, which participate in microRNA intracellular process and transfer. Our research demonstrated the expression and clinical role of the microRNA-regulating machinery in bladder cancer. EIF2C1, EIF2C2, Dicer, and Drosha mRNA and protein levels were analyzed in 100 bladder carcinomas and 50 normal bladder tissues using quantitative polymerase chain reaction and Western blotting. EIF2C2, Dicer, and Drosha mRNAs and proteins were overexpressed in carcinoma compared with normal tissues, whereas EIF2C1 mRNA and protein were not obviously different. Moreover, immunohistochemistry was used to detect the expressions of EIF2C2, Dicer, and Drosha in 100 bladder carcinomas. There were higher EIF2C2, Dicer, and Drosha expressions in carcinomas than in the adjacent normal tissues, positive correlations being noted with clinical stage, histopathologic grade, and recurrence. Higher EIF2C2, Dicer, and Drosha expressions were related to shorter cancer-specific survival and shorter recurrence-free survival. Multivariate Cox analysis showed that EIF2C2 was an important risk factor in bladder cancer. In conclusion, EIF2C2, Dicer, and Drosha are more highly expressed in bladder carcinoma, promote the development of bladder cancer, and suggested a poor prognosis. Their clinical role in bladder carcinoma merits further research.