MicroRNA-223-3p regulates cell chemo-sensitivity by targeting FOXO3 in prostatic cancer

Identification of prostate cancer associated genes for diagnosis and prognosis: a modernized in silico approach

Prostate cancer (PCa) ranks as the second leading cause of cancer-related deaths in men. Diagnosing PCa relies on molecular markers known as diagnostic biomarkers, while prognostic biomarkers are used to identify key proteins involved in PCa treatments. This study aims to gather PCa-associated genes and assess their potential as either diagnostic or prognostic biomarkers for PCa. A corpus of 152,064 PCa-related data from PubMed, spanning from May 1936 to December 2020, was compiled. Additionally, 4199 genes associated with PCa terms were collected from the National Center of Biotechnology Information (NCBI) database. The PubMed corpus data was extracted using pubmed.mineR to identify PCa-associated genes. Network and pathway analyses were conducted using various tools, such as STRING, DAVID, KEGG, MCODE 2.0, cytoHubba app, CluePedia, and ClueGO app. Significant marker genes were identified using Random Forest, Support Vector Machines, Neural Network algorithms, and the Cox Proportional Hazard model. This study reports 3062 unique PCa-associated genes along with 2518 corresponding unique PMIDs. Diagnostic markers such as IL6, MAPK3, JUN, FOS, ACTB, MYC, and TGFB1 were identified, while prognostic markers like ACTB and HDAC1 were highlighted in PubMed. This suggests that the potential target genes provided by PubMed data outweigh those in the NCBI database.

MiR-223-3p in Cancer Development and Cancer Drug Resistance: Same Coin, Different Faces

MicroRNAs (miRNAs) are mighty post-transcriptional regulators in cell physiology and pathophysiology. In this review, we focus on the role of miR-223-3p (henceforth miR-223) in various cancer types. MiR-223 has established roles in hematopoiesis, inflammation, and most cancers, where it can act as either an oncogenic or oncosuppressive miRNA, depending on specific molecular landscapes. MiR-223 has also been linked to either the sensitivity or resistance of cancer cells to treatments in a context-dependent way. Through this detailed review, we highlight that for some cancers (i.e., breast, non-small cell lung carcinoma, and glioblastoma), the oncosuppressive role of miR-223 is consistently reported in the literature, while for others (i.e., colorectal, ovarian, and pancreatic cancers, and acute lymphocytic leukemia), an oncogenic role prevails. In prostate cancer and other hematological malignancies, although an oncosuppressive role is frequently described, there is less of a consensus. Intriguingly, NLRP3 and FBXW7 are consistently identified as miR-223 targets when the miRNA acts as an oncosuppressor or an oncogene, respectively, in different cancers. Our review also describes that miR-223 was increased in biological fluids or their extracellular vesicles in most of the cancers analyzed, as compared to healthy or lower-risk conditions, confirming the potential application of this miRNA as a diagnostic and prognostic biomarker in the clinic.

A Meta-Analysis Approach to Gene Regulatory Network Inference Identifies Key Regulators of Cardiovascular Diseases

Cardiovascular diseases (CVDs) represent a major concern for global health, whose mechanistic understanding is complicated by a complex interplay between genetic predisposition and environmental factors. Specifically, heart failure (HF), encompassing dilated cardiomyopathy (DC), ischemic cardiomyopathy (ICM), and hypertrophic cardiomyopathy (HCM), is a topic of substantial interest in basic and clinical research. Here, we used a Partial Correlation Coefficient-based algorithm (PCC) within the context of a meta-analysis framework to construct a Gene Regulatory Network (GRN) that identifies key regulators whose activity is perturbed in Heart Failure. By integrating data from multiple independent studies, our approach unveiled crucial regulatory associations between transcription factors (TFs) and structural genes, emphasizing their pivotal roles in regulating metabolic pathways, such as fatty acid metabolism, oxidative stress response, epithelial-to-mesenchymal transition, and coagulation. In addition to known associations, our analysis also identified novel regulators, including the identification of TFs FPM315 and OVOL2, which are implicated in dilated cardiomyopathies, and TEAD1 and TEAD2 in both dilated and ischemic cardiomyopathies. Moreover, we uncovered alterations in adipogenesis and oxidative phosphorylation pathways in hypertrophic cardiomyopathy and discovered a role for IL2 STAT5 signaling in heart failure. Our findings underscore the importance of TF activity in the initiation and progression of cardiac disease, highlighting their potential as pharmacological targets.

Non-Coding RNAs and the Development of Chemoresistance to Docetaxel in Prostate Cancer: Regulatory Interactions and Approaches Based on Machine Learning Methods

Chemotherapy based on taxane-class drugs is the gold standard for treating advanced stages of various oncological diseases. However, despite the favorable response trends, most patients eventually develop resistance to this therapy. Drug resistance is the result of a combination of different events in the tumor cells under the influence of the drug, a comprehensive understanding of which has yet to be determined. In this review, we examine the role of the major classes of non-coding RNAs in the development of chemoresistance in the case of prostate cancer, one of the most common and socially significant types of cancer in men worldwide. We will focus on recent findings from experimental studies regarding the prognostic potential of the identified non-coding RNAs. Additionally, we will explore novel approaches based on machine learning to study these regulatory molecules, including their role in the development of drug resistance.

Deregulated microRNAs Involved in Prostate Cancer Aggressiveness and Treatment Resistance Mechanisms

Prostate cancer (PCa) is the most frequently diagnosed cancer and the second leading cause of cancer deaths among American men. Complex genetic and epigenetic mechanisms are involved in the development and progression of PCa. MicroRNAs (miRNAs) are short noncoding RNAs that regulate protein expression at the post-transcriptional level by targeting mRNAs for degradation or inhibiting protein translation. In the past two decades, the field of miRNA research has rapidly expanded, and emerging evidence has revealed miRNA dysfunction to be an important epigenetic mechanism underlying a wide range of diseases, including cancers. This review article focuses on understanding the functional roles and molecular mechanisms of deregulated miRNAs in PCa aggressiveness and drug resistance based on the existing literature. Specifically, the miRNAs differentially expressed (upregulated or downregulated) in PCa vs. normal tissues, advanced vs. low-grade PCa, and treatment-responsive vs. non-responsive PCa are discussed. In particular, the oncogenic and tumor-suppressive miRNAs involved in the regulation of (1) the synthesis of the androgen receptor (AR) and its AR-V7 splice variant, (2) PTEN expression and PTEN-mediated signaling, (3) RNA splicing mechanisms, (4) chemo- and hormone-therapy resistance, and (5) racial disparities in PCa are discussed and summarized. We further provide an overview of the current advances and challenges of miRNA-based biomarkers and therapeutics in clinical practice for PCa diagnosis/prognosis and treatment.

A Novel Defined PANoptosis-Related miRNA Signature for Predicting the Prognosis and Immune Characteristics in Clear Cell Renal Cell Carcinoma: A miRNA Signature for the Prognosis of ccRCC

Clear cell renal cell carcinoma (ccRCC) is one of the most prevalent cancers, and PANoptosis is a distinct, inflammatory-programmed cell death regulated by the PANoptosome. The essential regulators of cancer occurrence and progression are microRNAs (miRNAs). However, the potential function of PANoptosis-related microRNAs (PRMs) in ccRCC remains obscure. This study retrieved ccRCC samples from The Cancer Genome Atlas database and three Gene Expression Omnibus datasets. PRMs were recognized based on previous reports in the scientific literature. Regression analyses were used to identify the prognosis PRMs and construct a PANoptosis-related miRNA prognostic signature based on the risk score. We discovered that high-risk patients had poorer survival prognoses and were significantly linked to high-grade and advanced-stage tumors, using a variety of R software packages and web analysis tools. Furthermore, we demonstrated that the low-risk group had significant changes in their metabolic pathways. In contrast, the high-risk group was characterized by high immune cell infiltration, immune checkpoint expression, and low half-maximum inhibition concentration (IC50) values of chemotherapeutic agents. This suggests that high-risk patients may benefit more from immunotherapy and chemotherapy. In conclusion, we constructed a PANoptosis-related microRNA signature and revealed its potential significance in clinicopathological features and tumor immunity, thereby providing new precise treatment strategies.

MicroRNAs as master regulators of FOXO transcription factors in cancer management

MicroRNAs are critical regulators of the plethora of genes, including FOXO "forkhead" dependent transcription factors, which are bonafide tumour suppressors. The FOXO family members modulate a hub of cellular processes like apoptosis, cell cycle arrest, differentiation, ROS detoxification, and longevity. Aberrant expression of FOXOs in human cancers has been observed due to their down-regulation by diverse microRNAs, which are predominantly involved in tumour initiation, chemo-resistance and tumour progression. Chemo-resistance is a major obstacle in cancer treatment. Over 90% of casualties in cancer patients are reportedly associated with chemo-resistance. Here, we have primarily discussed the structure, functions of FOXO and also their post-translational modifications which influence the activities of these FOXO family members. Further, we have addressed the role of microRNAs in carcinogenesis by regulating the FOXOs at post-transcriptional level. Therefore, microRNAs-FOXO axis can be exploited as a novel cancer therapy. The administration of microRNA-based cancer therapy is likely to be beneficial to curb chemo-resistance in cancers.

MicroRNA-223-3p inhibits oxidized low-density lipoprotein-mediated NLRP3 inflammasome activation via directly targeting NLRP3 and FOXO3

BACKGROUND

MicroRNAs (miRNAs) have emerged as crucial players in the initiation and development of atherosclerosis (AS), and the low miR-223-3p level is observed in AS patients. However, the function and mechanism behind miR-223-3p in AS progression have not been fully elucidated.

METHOD

In the present study, THP-1 cells treated with oxidized low-density lipoprotein (ox-LDL) were employed as the cell model of AS. The expression levels of miR-223-3p, NLR family pyrin domain containing 3 (NLRP3), caspase-1, pro-caspase-1, cleaved interleukin 18 (IL-18), cleaved IL-1β, and forkhead box O3 (FOXO3) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot (WB) analyses. The relationship between miR-223-3p and FOXO3 or NLRP3 was determined using a dual-luciferase reporter assay. The production of IL-1β, IL-18, IL-6, and TNF-α was examined by Enzyme-linked immunosorbent assay (ELISA).

RESULTS

MiR-223-3p was decreased in AS patients and ox-LDL-induced THP-1 cells, and its upregulation downregulated the abundance of NLRP3, caspase-1, cleaved IL-18, cleaved IL-1β, IL-1β, IL-6, and TNF-α in THP-1 cells treated with ox-LDL or not, and the depletion of miR-223-3p revealed an opposite phenomenon. NLPR3 and FOXO3 were identified as two authentic targets of miR-223-3p. Knockdown of NLRP3 or FOXO3 reversed the stimulatory effect of the miR-223-3p inhibitor on the inflammatory responses of THP-1 cells.

CONCLUSIONS

Our data indicate that miR-223-3p inhibited ox-LDL-mediated NLRP3 inflammasome activation via directly targeting NLRP3 and FOXO3 in THP-1 cells, which offered a prospective therapeutic target for AS therapy.

FOXO3a and Its Regulators in Prostate Cancer

Forkhead box O3 (FOXO3a) is a member of a subfamily of forkhead transcription factors involved in the basic processes within a cell, including proliferation, apoptosis, cell cycle regulation, and DNA damage. As a transcription factor, FOXO3a is involved in the response to cellular stress, UV radiation, or oxidative stress. Its regulation is based on the modification of proteins as well as regulation by other proteins, e.g., growth factors. FOXO3a is commonly deregulated in cancer cells, and its inactivation is associated with initiation and progression of tumorigenesis, suggesting its role as a tumor suppressor; however, its role is still disputed and seems to be dependent on upstream signaling. Nevertheless, FOXO3a serves as an interesting potential target in therapies as it is regulated during treatment with very common anti-cancer drugs such as paclitaxel, cisplatin, docetaxel, and doxorubicin. This review aims to update the reported role of FOXO3a in prostate cancer (PCa), with a focus on its regulators that might serve as potential therapeutic agents in PCa therapy.

miR-92a promotes proliferation and inhibits apoptosis of prostate cancer cells through the PTEN/Akt signaling pathway

MicroRNAs (miRNAs) play an important role in the development of prostate cancer (PCa). Recent studies have shown that miR-92a expression is significantly increased in various cancers including PCa. However, its specific mechanism in PCa remains unknown. The goal of this study was to investigate the effect of miR-92a expression on the function and mechanism of PCa. PCa cell lines PC-3 and LNCap were transfected with miR-92a inhibitor to reduce the expression of miR-92a, respectively. The cell proliferation, cell viability, apoptosis, cell invasion and migration ability of PCa cells were examined by CCK8 assay, cell cloning, flow cytometry, Transwell assay and scratch assay, respectively. The effects of miR-92a on PTEN/Akt signaling pathway-related factors (PI3k, Akt, p-PI3k, p-Akt, PTEN) were also observed by RT-qPCR and Western blot. Compared with the control group and NC inhibitor group, the viability, cell migration and invasion ability of PC-3 and LNCap cells were decreased and apoptosis was significantly increased after interference with miR-92a expression. In addition, the mRNA and protein levels of PTEN in PC-3 and LNCap cells in the miR-92a inhibitor group were significantly increased, while the phosphorylation levels of PI3K and AKT were significantly decreased. MiR-92a might play a key role in regulating the proliferation, migration and invasion of PCa cells through the PTEN/Akt signaling pathway. Inhibition of miR-92a expression has practical value against PCa and provides ideas for further clinical treatment of patients with PCa.

The miRNAs involved in prostate cancer chemotherapy response as chemoresistance and chemosensitivity predictors

BACKGROUND

Reliable molecular markers that allow the rational prescription of an effective chemotherapy type for each prostate cancer patient are still needed. Since microRNAs expression is associated with the response to different types of prostate cancer therapy, microRNAs represent a pool of perspective markers of therapy effectiveness comprising chemotherapy.

OBJECTIVES

The available data on microRNAs associated with chemotherapy response (resistance and sensitivity) are summarized and analyzed in the article.

MATERIALS AND METHODS

A review of the published data, as well as their analysis by current bioinformatics resources, was conducted. The molecular targets of microRNAs, as well as the reciprocal relationships between the microRNAs and their targets, were studied using the DIANA, STRING, and TransmiR databases. Special attention was dedicated to the mechanisms of prostate cancer chemoresistance development.

RESULTS AND DISCUSSION

The combined analysis of bioinformatics resources and the available literature indicated that the expression of eight microRNAs that are associated with different responses to chemotherapy have a high potential for the prediction of the prostate cancer chemotherapy response, as found in the experiments and confirmed by the functions of regulated genes.

CONCLUSION

An overview on the published data and bioinformatics resources, with respect to predictive microRNA markers of chemotherapy response, is presented in this review. The selected microRNA and gene panel has a high potential for predicting the chemosensitivity or chemoresistance of prostate cancer and could represent a set of markers for subsequent study using samples of cell-free microRNAs from different patient groups.

MiR-223-3p targets FOXO3a to inhibit radiosensitivity in prostate cancer by activating glycolysis

AIMS

The incidence and detection rate of prostate cancer in China have been increasing in recent years. Radiotherapy is the ideal treatment for non-metastatic prostate cancer (PCa), but the effectiveness of radiotherapy is greatly discounted due to radio resistance. Therefore, relieving the radiotherapy resistance of PCa is key to improve the clinical efficacy of PCA.

MAIN METHODS

Cell proliferation was estimated using the MTT and clone formation assays. Cell apoptosis was estimated using the Annexin V-FITC/propidium iodide (PI) staining assay. Glucose uptake and lactose and ATP production were used to detect glycolysis.

KEY FINDINGS

miR-223-3p was significantly upregulated in clinically collected urine samples and PCa cells with low radiosensitivity. Enhancing miR-223-3p reduced radiosensitivity further, while inhibiting miR-223-3p improved the radiosensitivity of PC3 and LNCaP cells. Importantly, miR-223-3p regulated radiosensitivity by enhancing cell glycolysis. FOXO3a was a key target of miRNA-223-3p regulating glycolysis and radiosensitivity. Overexpression of FOXO3a abated the glycolysis level and alleviated the radioresistance caused by enhancing miR-223-3p to a certain extent.

SIGNIFICANCE

This is novel research on the role of miR-223-3p in promoting radiotherapy resistance of PCa cells by activating glycolysis. This approach provides a new perspective and ideas for alleviating radiotherapy resistance of PCa cells.

MicroRNAs as Epigenetic Determinants of Treatment Response and Potential Therapeutic Targets in Prostate Cancer

Prostate cancer (PCa) is the second most common tumor in men worldwide, and the fifth leading cause of male cancer-related deaths in western countries. PC is a very heterogeneous disease, meaning that optimal clinical management of individual patients is challenging. Depending on disease grade and stage, patients can be followed in active surveillance protocols or undergo surgery, radiotherapy, hormonal therapy, and chemotherapy. Although therapeutic advancements exist in both radiatiotherapy and chemotherapy, in a considerable proportion of patients, the treatment remains unsuccessful, mainly due to tumor poor responsiveness and/or recurrence and metastasis. microRNAs (miRNAs), small noncoding RNAs that epigenetically regulate gene expression, are essential actors in multiple tumor-related processes, including apoptosis, cell growth and proliferation, autophagy, epithelial-to-mesenchymal transition, invasion, and metastasis. Given that these processes are deeply involved in cell response to anti-cancer treatments, miRNAs have been considered as key determinants of tumor treatment response. In this review, we provide an overview on main PCa-related miRNAs and describe the biological mechanisms by which specific miRNAs concur to determine PCa response to radiation and drug therapy. Additionally, we illustrate whether miRNAs can be considered novel therapeutic targets or tools on the basis of the consequences of their expression modulation in PCa experimental models.

The miR-223-3p/MAP1B axis aggravates TGF-β-induced proliferation and migration of BPH-1 cells

Uncontrolled proliferation and migration of benign prostatic hyperplasia (BPH) epithelial cells play a critical role in the pathogenesis of BPH. The regulatory roles of microRNAs (miRNAs) in multiple human diseases have been observed. This study was dedicated to investigating the regulatory effects of the miR-223-3p on the proliferation and migration of BPH progress. In the present study, the aberrant upregulation of miR-223-3p in BPH samples and BPH-1 cells was determined. TGF-β stimulation induced miR-223-3p expression, promoted BPH-1 cell viability and DNA synthesis, inhibited BPH-1 cell apoptosis, and decreased pro-apoptotic Bax/caspase 3. These changes induced by TGF-β stimulation were further enhanced the overexpression of miR-223-3p and attenuated via the inhibition of miR-223-3p. Under TGF-β stimulation, the overexpression of miR-223-3p enhanced, whereas the inhibition of miR-223-3p inhibited the EMT and MAPK signaling pathways. By targeting the MAP1B 3'UTR, miR-223-3p repressed MAP1B expression. In contrast to miR-223-3p overexpression, MAP1B overexpression attenuated TGF-β-induced changes in BPH-1 cell phenotypes, pro-apoptotic Bax/caspase 3, and the EMT and MAPK signaling pathways; more importantly, MAP1B overexpression significantly attenuated the roles of miR-223-3p overexpression in BPH-1 cell phenotypes, pro-apoptotic Bax/caspase 3, and the EMT and MAPK signaling pathways under TGF-β stimulation. In conclusion, miR-223-3p aggravates the uncontrolled proliferation and migration of BPH-1 cells through targeting MAP1B. The EMT and MAPK signaling pathways might be involved.

MiR-940 promotes malignant progression of breast cancer by regulating FOXO3

Breast cancer (BC) is a common cancer with poor survival. The present study aimed to explore the effect of miR-940 on the process of BC cells and its target gene FOXO3. The expression of miR-940 was assessed in BC tissues and cells using qRT-PCR. Furthermore, the correlation between miR-940 and prognosis of BC patients from the TCGA database was analyzed. CCK8 assays and colony formation assays were used to explore the effect of miR-940 on BC cell proliferation. The invasion abilities were detected by transwell assays. Luciferase reporter assay was performed to scrutinize the relationship between miR-940 and FOXO3. Finally, rescue experiments were performed through FOXO3 down-regulation and miR-940 inhibitors by using CCK8 assays, colony formation assays and transwell assays. miR-940 was significantly up-regulated in BC cells and tissues. In addition, the high level of miR-940 correlated with poor survival of BC patients (P=0.023). CCK8 assays, colony formation assays and transwell assays indicated that miR-940 promoted the proliferation and invasion abilities of BC cells. The luciferase reporter assay suggested that miR-940 directly targeted FOXO3. Moreover, we found that the effect of si-FOXO3 was rescued by miR-940 inhibitors in BC cells. miR-940 may promote the proliferation and invasion abilities of BC cells by targeting FOXO3. Our study suggested that miR-940 could be a novel molecular target for therapies against BC.

Mechanisms of docetaxel resistance in prostate cancer: The key role played by miRNAs

One of the main problems with the treatment of metastatic prostate cancer is that, despite an initial positive response, the majority of patients develop resistance and progress. In particular, the resistance to docetaxel, the gold standard therapy for metastatic prostate cancer since 2010, represents one of the main factors responsible for the failure of prostate cancer therapy. According to the present knowledge, different processes contribute to the appearance of docetaxel resistance and non-coding RNA seems to play a relevant role in them. In this review, a comprehensive overview of the miRNA network involved in docetaxel resistance is described, highlighting the pathway/s affected by their activity.

FOXO3 is targeted by miR-223-3p and promotes osteogenic differentiation of bone marrow mesenchymal stem cells by enhancing autophagy

Mesenchymal stem cells (MSCs) are a promising regenerative medicine. The roles of miRNAs in osteogenic differentiation of bone marrow MSCs (BM-MSCs) remained less reported. Forkhead Box O3 (FOXO3) and alkaline phosphatase (ALP) levels in the BM-MSCs were measured on 3, 7, and 14 days after osteogenic differentiation. After transfection of FOXO3 overexpression plasmids or siFOXO3 into BM-MSCs, factors related to osteogenic differentiation or cell autophagy were determined. Besides, 3-methyladenine or rapamycin, as well as miR-223-3p mimic or inhibitor were applied to further determine the effect of FOXO3 in BM-MSCs. FOXO3 and ALP levels were increased in a time-dependent manner with osteogenic differentiation, supported by Alizarin Red Staining. Furthermore, up-regulated FOXO3 increased levels of ALP and factors related to osteogenic differentiation by increasing levels of autophagy-related factors. FOXO3, targeted by miR-223-3p, reversed the effects of miR-223-3p on factors related to BM-MSC autophagy and osteogenic differentiation. Down-regulated miR-223-3p expression promoted osteogenic differentiation of BM-MSCs by enhancing autophagy via targeting FOXO3, suggesting the potential of miR-223-3p as a therapeutic target for enhancing bone functions.

miR-629 targets FOXO3 to promote cell apoptosis in gastric cancer

Gastric cancer (GC) is one of the most aggressive types of human tumor worldwide, and the 5-year survival rate is less than 25%. The transcriptional factor, forkhead box O3 (FOXO3), is regulated by various micro (mi)RNAs and has been reported to be associated with multiple regulatory signaling pathways involved in tumor development. The current study therefore assessed the impact of miR-629 and FOXO3 on gastric cancer. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to assess the expression of mRNA and protein, respectively. Additionally, the cell proliferation and apoptosis rate were determined via an MTT assay and flow cytometry, respectively. The online database TargetScan predicted that FOXO3 was a target of miR-629. A luciferase reporter assay was also performed to verify that FOXO3 was the direct target of miR-629. The results demonstrated that miR-629 and FOXO3 was upregulated and downregulated in GC tissue, respectively. Furthermore, following transfection with a miR-629 inhibitor, SGC-7901, cell proliferation and apoptosis rate were inhibited and promoted when compared with the control group, respectively. Moreover, after the treatment with SGC-7901, the expression of FOXO3, Bax, Caspase 3 was upregulated, and Bcl-2 was downregulated. Furthermore, the luciferase reporter assay revealed that FOXO3 was the target of miR-629. The results demonstrated that miR-629 and FOXO3 serve vital roles in the development of gastric cancer and may be a future therapeutic target.

miR-3622b-5p regulates cisplatin resistance of human gastric cancer cell line by targeting BIRC5

Many evidences showed that drug resistance of gastric cancer cells could be regulated by the abnormal expression of microRNAs (miRNAs), a post-transcriptional regulator of gene expression. Thus, we investigated the role of miR-3622b-5p in the development of cisplatin (DDP) resistance in human gastric cancer cell lines. A set of biochemical assays were used to elucidate the mechanism by which miR-3622b-5p regulates drug resistance in cancer cells. The expression of miR-3622b-5p was measured by quantitative real-time PCR and showed that miR-3622b-5p was significantly downregulated in the plasma of patients with acquired drug resistance to platinum-based chemotherapy for gastric cancer. miR-3622b-5p was also found significantly downregulated in DDP-resistant gastric cancer cell line SGC7901/DDP, compared with the parental SGC7901 cells. An in vitro drug sensitivity assay showed that overexpression of miR-3622b-5p sensitized SGC7901/DDP cells to DDP. The luciferase activity of reporters constructed by BIRC5 3′-untranslated regions in SGC7901/DDP cells suggested that BIRC5 was target gene of miR-3622b-5p. Ecpotic miR-3622b-5p expression in SGC7901/DDP cells significantly repressed the expression of the BIRC5 and sensitized the cells to DDP-induced apoptosis. By contrast, treatment with miR-3622b-5p inhibitor increased the protein expression of BIRC5 and led to a lower proportion of apoptotic cells in the SGC7901 cells. In conclusion, our findings suggest that miR-3622b-5p regulates DDP resistance of human gastric cancer cells at least in part by repressing the expression of BIRC5. Altering miR-3622b-5p expression may be a potential therapeutic strategy for the treatment of chemoresistance in gastric cancer in the future.

miR-223-3p promotes autoreactive Th17 cell responses in experimental autoimmune uveitis (EAU) by inhibiting transcription factor FOXO3 expression

Pathogenic T helper (T_h)17 cells are key mediators of autoimmune diseases such as uveitis and its animal model, experimental autoimmune uveitis (EAU). However, the contribution of microRNAs (miRs) to the intrinsic control of pathogenic T_h17 cells in EAU remains largely unknown. Here, we have reported that miR-223-3p was significantly up-regulated in interphotoreceptor retinoid-binding protein-specific T_h17 cells, and its expression was enhanced by IL-23-signal transducer and activator of transcription 3 signaling. Knockdown of miR-223-3p decreased the pathogenicity of T_h17 cells in a T-cell transfer model of EAU. Mechanistic studies showed that miR-223-3p directly repressed the expression of forkhead box O3 (FOXO3), and FOXO3 negatively regulated pathogenic T_h17 cell responses partially via suppression of IL-23 receptor expression. Thus, our results reveal an important role for miR-223-3p in autoreactive T_h17 cell responses and suggest a potential therapeutic avenue for uveitis.-Wei, Y., Chen, S., Sun, D., Li, X., Wei, R., Li, X., Nian, H. miR-223-3p promotes autoreactive T_h17 cell responses in experimental autoimmune uveitis (EAU) by inhibiting transcription factor FOXO3 expression.

Semen miRNAs Contained in Exosomes as Non-Invasive Biomarkers for Prostate Cancer Diagnosis

Although it is specific for prostatic tissue, serum prostate-specific antigen (PSA) screening has resulted in an over-diagnosis of prostate cancer (PCa) and many unnecessary biopsies of benign disease due to a well-documented low cancer specificity, thus improvement is required. We profiled the expression level of miRNAs contained in semen exosomes from men with moderately increased PSA levels to assess their usefulness, either alone or in addition to PSA marker, as non-invasive biomarkers, for the early efficient diagnosis and prognosis of PCa. An altered miRNA expression pattern was found by a high throughput profiling analysis in PCa when compared with healthy individuals (HCt) exosomal semen samples. The presence of vasectomy was taken into account for the interpretation of results. Fourteen miRNAs were selected for miRNA validation as PCa biomarkers in a subsequent set of semen samples. In this explorative study, we describe miRNA-based models, which included miRNA expression values together with PSA levels, that increased the classification function of the PSA screening test with diagnostic and/or prognostic potential: [PSA + miR-142-3p + miR-142-5p + miR-223-3p] model (AUC:0,821) to discriminate PCa from BPH (Sn:91,7% Sp:42,9% vs Sn:100% Sp:14,3%); and [PSA + miR-342-3p + miR-374b-5p] model (AUC: 0,891) to discriminate between GS ≥ 7 tumours and men presenting PSA ≥ 4 ng/ml with no cancer or GS6 tumours (Sn:81,8% Sp:95% vs Sn:54,5% Sp:90%). The pathway analysis of predicted miRNA target genes supports a role for these miRNAs in PCa aetiology and/or progression. Our study shows semen exosome miRNA-based models as molecular biomarkers with the potential to improve PCa diagnosis/prognosis efficiency. As the next step, further prospective studies on larger cohorts of patients are required to validate the diagnostic and/or prognostic role of the miRNA panel before it could be adopted into clinical practice.

MicroRNA-194 regulates cell viability and apoptosis by targeting CDH2 in prostatic cancer

Introduction

Prostate cancer (PCa) is one of the most common malignancies in men. However, a lack of understanding of the mechanism underlying PCa metastasis has strongly limited the effectiveness of therapy for this disease. Thus, investigating the mechanism of PCa may help improve the prognosis of PCa patients. The goal of this study was to investigate the role of microRNA-194 (miR-194) in PCa.

Materials and methods

The expression of miR-194 and cadherin 2 (CDH2) at the transcriptional level was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The MTT assay cell apoptosis assay and Western blotting were used to determine the role of miR-194 and CDH2 in the PC3 human PCa cell line. The dual luciferase reporter assay system was performed to clarify the relationship between miR-194 and CDH2. qRT-PCR results showed that miR-194 was downregulated and CDH2 was upregulated in PC3 cells.

Results

Transfection with miR-194 mimics decreased cell viability and increased the rate of apoptosis compared with the control group of PC3 cells. Bioinformatics and the luciferase reporter assay indicated that CDH2 was a target of miR-194, and Western blot analysis suggested that CDH2 was negatively regulated by miR-194. Further studies revealed that the downregulation of CDH2 suppressed cell viability and promoted the apoptosis of PC3 cells and that miR-194 directly targeted CDH2 in PC3 cells. Finally, the in vivo experiments showed that miR-194 mimics suppressed tumor growth and induced apoptosis in a greater proportion of cells by decreasing the expression of CDH2 compared with the control group.

Conclusion

The results of this study showed that miR-194 targeted CDH2 to regulate PCa cell survival in vitro and suppress tumor growth in vivo. These findings suggest that miR-194 may be a useful therapeutic target in PCa.