miR-205 regulates the proliferation and invasion of ovarian cancer cells via suppressing PTEN/SMAD4 expression

Clinical relevance of exosome-derived microRNAs in Ovarian Cancer: Looking for new tumor biological fingerprints

Specific tumor-derived extracellular vesicles, called exosomes, are considered as potential key players in cross-talk between immune system and tumor microenvironment in several solid tumors. Different studies highlighted the clinical relevance of exosomes in ovarian cancer (OC) for their role in early diagnosis, prognosis, chemoresistance, targeted therapy. The exosomes are nanosize vesicles carrying lipids, proteins, and nucleic acids. In particular, exosomes shuttle a wide spectrum of microRNAs (miRNAs) able to induce phenotypic reprogramming of target cells, contributing to tumor progression. In this review, we will discuss the promising role of miRNAs shuttled by exosomes, called exosomal miRNAs (exo-miRNAs), as potential biomarkers for early detection, tumour progression and metastasis, prognosis, and response to therapy in OC women, in order to search for new potential biological fingerprints able to better characterize the evolution of this malignancy and provide a clinically relevant non-invasive approach useful for adopting, in future, personalized therapeutic strategies.

MicroRNAs, long non-coding RNAs, and circular RNAs and gynecological cancers: focus on metastasis

Gynecologic cancer is a significant cause of death in women worldwide, with cervical cancer, ovarian cancer, and endometrial cancer being among the most well-known types. The initiation and progression of gynecologic cancers involve a variety of biological functions, including angiogenesis and metastasis-given that death mostly occurs from metastatic tumors that have invaded the surrounding tissues. Therefore, understanding the molecular pathways underlying gynecologic cancer metastasis is critical for enhancing patient survival and outcomes. Recent research has revealed the contribution of numerous non-coding RNAs (ncRNAs) to metastasis and invasion of gynecologic cancer by affecting specific cellular pathways. This review focuses on three types of gynecologic cancer (ovarian, endometrial, and cervical) and three kinds of ncRNAs (long non-coding RNAs, microRNAs, and circular RNAs). We summarize the detailed role of non-coding RNAs in the different pathways and molecular interactions involved in the invasion and metastasis of these cancers.

Diagnostics and Therapeutic Potential of miR-205 and miR-34a in Ovarian Cancer Management: A miRNA-Target-Based Analysis

Epithelial ovarian cancer (EOC) treatment strategies mainly focused on surgery combined with chemotherapy. Recent targeted therapy techniques emerge as milestone and could be used for management of ovarian cancer (OC) progression with more efficacy. The aim is to evaluate the therapeutic and diagnostic potential of microRNA (miRNA) in management of EOC using in silico and quantitative real-time PCR (qRT-PCR) expression analysis. We performed functional enrichment and miRNA-Target genes expression analysis in 48 EOC and 22 normal tissue samples using qRT-PCR and correlated with miRNA expression data in matched samples to evaluate the diagnostic and therapeutic potential of miRNA in OC management. In silico functional enrichment analysis revealed miRNA association with disease. Target genes of miRNAs participate in several biologically important pathways leading to cancer progression. Targets of miRNA-205 and miRNA-34a were significantly downregulated, and upregulated, respectively, in EOC. Moreover, significant negative correlation between relative expression of miRNA-205 and target genes (BCL2, ZEB1, E2F1, and TP53) was observed with r = -0.813; r = -0.755; r = -0.559; and r = -0.767, respectively. Similarly, miRNA-34a also showed higher negative correlation with target genes (MDM4, MAPK3, BRCA1, AREG) with r = -0.840; r = -0.870; r = -0.622; and r = -0.623, respectively. In addition, receiver operating characteristics analysis of combined miRNA panel, miRNA-205-Target gene panel, and miRNA-34a-Target gene panel exhibited higher diagnostics value with area under the curve (AUC) of 92.7 (p < 0.0001), 94.8 (p < 0.0001), and 98.3 (p < 0.0001), respectively. Negative Correlation between miRNA and target genes expression data in matched samples highlights therapeutic potential of miRNA in EOC management. Moreover, combined diagnostic potential of miRNA-target gene panel could predict risk of EOC with higher AUC, sensitivity, and specificity.

A comprehensive survey into the role of microRNAs in ovarian cancer chemoresistance; an updated overview

Ovarian cancer (OC), a frequent malignant tumor that affects women, is one of the leading causes of cancer-related death in this group of individuals. For the treatment of ovarian cancer, systemic chemotherapy with platinum-based drugs or taxanes is the first-line option. However, drug resistance developed over time during chemotherapy medications worsens the situation. Since uncertainty exists for the mechanism of chemotherapy resistance in ovarian cancer, there is a need to investigate and overcome this problem. miRNAs are engaged in various signaling pathways that contribute to the chemotherapeutic resistance of ovarian cancer. In the current study, we have tried to shed light on the mechanisms by which microRNAs contribute to the drug resistance of ovarian cancer and the use of some microRNAs to combat this chemoresistance, leading to the worse outcome of ovarian cancer patients treated with systemic chemotherapeutics.

Role of different non-coding RNAs as ovarian cancer biomarkers

Background

Among many gynecological malignancies ovarian cancer is the most prominent and leading cause of female mortality worldwide. Despite extensive research, the underlying cause of disease progression and pathology is still unknown. In the progression of ovarian cancer different non-coding RNAs have been recognized as important regulators. The biology of ovarian cancer which includes cancer initiation, progression, and dissemination is found to be regulated by different ncRNA. Clinically ncRNA shows high prognostic and diagnostic importance.

Results

In this review, we prioritize the role of different non-coding RNA and their perspective in diagnosis as potential biomarkers in the case of ovarian cancer. Summary of some of the few miRNAs involved in epithelial ovarian cancer their expression and clinical features are being provided in the table. Also, in cancer cell proliferation, apoptosis, invasion, and migration abnormal expression of piRNAs are emerging as a crucial regulator hence the role of few piRNAs is being given. Both tRFs and tiRNAs play important roles in tumorigenesis and are promising diagnostic biomarkers and therapeutic targets for cancer. lncRNA has shown a leading role in malignant transformation and potential therapeutic value in ovarian cancer therapy.

Conclusions

Hence in this review we demonstrated the role of different ncRNA that play an important role in serving strong potential as a therapeutic approach for the treatment of ovarian cancer.

ROS and miRNA Dysregulation in Ovarian Cancer Development, Angiogenesis and Therapeutic Resistance

The diverse repertoires of cellular mechanisms that progress certain cancer types are being uncovered by recent research and leading to more effective treatment options. Ovarian cancer (OC) is among the most difficult cancers to treat. OC has limited treatment options, especially for patients diagnosed with late-stage OC. The dysregulation of miRNAs in OC plays a significant role in tumorigenesis through the alteration of a multitude of molecular processes. The development of OC can also be due to the utilization of endogenously derived reactive oxygen species (ROS) by activating signaling pathways such as PI3K/AKT and MAPK. Both miRNAs and ROS are involved in regulating OC angiogenesis through mediating multiple angiogenic factors such as hypoxia-induced factor (HIF-1) and vascular endothelial growth factor (VEGF). The NAPDH oxidase subunit NOX4 plays an important role in inducing endogenous ROS production in OC. This review will discuss several important miRNAs, NOX4, and ROS, which contribute to therapeutic resistance in OC, highlighting the effective therapeutic potential of OC through these mechanisms.

Combination microRNA-based cellular reprogramming with paclitaxel enhances therapeutic efficacy in a relapsed and multidrug-resistant model of epithelial ovarian cancer

Most advanced-stage ovarian cancer patients, including those with epithelial ovarian cancer (EOC), develop recurrent disease and acquisition of resistance to chemotherapy, leading to limited treatment options. Decrease in Let7b miRNA levels in clinical ovarian cancer has been associated with chemoresistance, increased proliferation, invasion, and relapse in EOC. We have established a murine EOC relapsed model by administering paclitaxel (PTX) and stopping therapy to allow for tumor regrowth. Global microRNA profiling in the relapsed tumor showed significant downregulation of Let7b relative to untreated tumors. Here, we report the use of hyaluronic acid (HA)-based nanoparticle formulation that can deliver Let7b miRNA mimic to tumor cells and achieve cellular programming both in vitro and in vivo. We demonstrate that a therapeutic combination of Let7b miRNA and PTX leads to significant improvement in anti-tumor efficacy in the relapsed model of EOC. We further demonstrate that the combination therapy is safe for repeated administration. This novel approach of cellular reprogramming of tumor cells using clinically relevant miRNA mimic in combination with chemotherapy could enable more effective therapeutic outcomes for patients with advanced-stage relapsed EOC.

Exosomal miR-205-5p enhances angiogenesis and nasopharyngeal carcinoma metastasis by targeting desmocollin-2

The aim of this study was to investigate whether and how exosomal miR-205-5p regulated angiogenesis and nasopharyngeal carcinoma (NPC) metastasis. We found that up-regulated serum exosomal miR-205-5p levels were associated with NPC progression and worse overall survival of NPC patients. miR-205-5p over-expression significantly increased tube formation, wound healing, migration and invasion of NPC cells, and lung metastasis of NPC tumors, whereas miR-205-5p inhibition had opposite effects. Exosomal miR-205-5p from NPC cells promoted the migration, tube formation, and microvessel density (MVD) of HUVECs in vitro and in vivo. Furthermore, bioinformatics-, luciferase reporter-, and biotinylated miR-205-5p-based pull-down assays indicated that miR-205-5p directly bound to the 3′ UTR of desmocollin-2 (DSC2). Exosomal miR-205-5p targeted DSC2 to enhance the EGFR/ERK signaling and MMP2/MMP9 expression, promoting angiogenesis and NPC metastasis, which was abrogated by DSC2 over-expression. Finally, the levels of miR-205-5p transcripts were positively correlated with MVD but negatively with DSC2 expression in NPC tissues, and patients with miR-205^high/DSC2^low NPC had worse overall survival. In conclusion, exosomal miR-205-5p promotes angiogenesis and NPC metastasis by targeting DSC2 to enhance EGFR/ERK signaling and MMP expression. This exosomal/miR-205-5p/EGFR/ERK axis may be a new therapeutic target for intervention of NPC metastasis.

Multiple roles of mothers against decapentaplegic homolog 4 in tumorigenesis, stem cells, drug resistance, and cancer therapy

The transforming growth factor (TGF)-β signaling pathway controls many cellular processes, including proliferation, differentiation, and apoptosis. Abnormalities in the TGF-β signaling pathway and its components are closely related to the occurrence of many human diseases, including cancer. Mothers against decapentaplegic homolog 4 (Smad4), also known as deleted in pancreatic cancer locus 4, is a typical tumor suppressor candidate gene locating at q21.1 of human chromosome 18 and the common mediator of the TGF-β/Smad and bone morphogenetic protein/Smad signaling pathways. It is believed that Smad4 inactivation correlates with the development of tumors and stem cell fate decisions. Smad4 also interacts with cytokines, miRNAs, and other signaling pathways, jointly regulating cell behavior. However, the regulatory function of Smad4 in tumorigenesis, stem cells, and drug resistance is currently controversial. In addition, Smad4 represents an attractive therapeutic target for cancer. Elucidating the specific role of Smad4 is important for understanding the mechanism of tumorigenesis and cancer treatment. Here, we review the identification and characterization of Smad4, the canonical TGF-β/Smad pathway, as well as the multiple roles of Smad4 in tumorigenesis, stem cells, and drug resistance. Furthermore, we provide novel insights into the prospects of Smad4-targeted cancer therapy and the challenges that it will face in the future.

The biochemical and clinical implications of phosphatase and tensin homolog deleted on chromosome ten in different cancers

Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is widely known as a tumor suppressor gene. It is located on chromosome 10q23 with 200 kb, and has dual activity of both protein and lipid phosphatase. In addition, as a targeted gene in multiple pathways, PTEN has a variety of physiological activities, such as those regulating the cell cycle, inducing cell apoptosis, and inhibiting cell invasion, etc. The PTEN gene have been identified in many kinds of cancers due to its mutations, deletions and inactivation, such as lung cancer, liver cancer, and breast cancer, and they are closely connected with the genesis and progression of cancers. To a large extent, the tumor suppressive function of PTEN is realized through its inhibition of the PI3K/AKT signaling pathway which controls cells apoptosis and development. In addition, PTEN loss has been associated with the prognosis of many cancers, such as lung cancer, liver cancer, and breast cancer. PTEN gene is related to many cancers and their pathological development. On the basis of a large number of related studies, this study describes in detail the structure, regulation, function and classical signal pathways of PTEN, as well as the relationship between various tumors related to PTEN. In addition, some drug studies targeting PTEN/PI3K/AKT/mTOR are also introduced in order to provide some directions for experimental research and clinical treatment of tumors.

Evaluation of Diagnostic Potential of Epigenetically Deregulated MiRNAs in Epithelial Ovarian Cancer

Background

Epithelial ovarian cancer (EOC) is one of the most lethal gynecological malignancies among women worldwide. Early diagnosis of EOC could help in ovarian cancer management. MicroRNAs, a class of small non-coding RNA molecules, are known to be involved in post-transcriptional regulation of ~60% of human genes. Aberrantly expressed miRNAs associated with disease progression are confined in lipid or lipoprotein and secreted as extracellular miRNA in body fluid such as plasma, serum, and urine. MiRNAs are stably present in the circulation and recently have gained an importance to serve as a minimally invasive biomarker for early detection of epithelial ovarian cancer.

Methods

Genome-wide methylation pattern of six EOC and two normal ovarian tissue samples revealed differential methylation regions of miRNA gene promoter through MeDIP-NGS sequencing. Based on log2FC and p-value, three hypomethylated miRNAs (miR-205, miR-200c, and miR-141) known to have a potential role in ovarian cancer progression were selected for expression analysis through qRT-PCR. The expression of selected miRNAs was analyzed in 115 tissue (85 EOC, 30 normal) and 65 matched serum (51 EOC and 14 normal) samples.

Results

All three miRNAs (miR-205, miR-200c, and miR-141) showed significantly higher expression in both tissue and serum cohorts when compared with normal controls (p < 0.0001). The receiver operating characteristic curve analysis of miR-205, miR-200c, and miR-141 has area under the curve (AUC) values of 87.6 (p < 0.0001), 78.2 (p < 0.0001), and 86.0 (p < 0.0001), respectively; in advance-stage serum samples, however, ROC has AUC values of 88.1 (p < 0.0001), 78.9 (p < 0.0001), and 86.7 (p < 0.0001), respectively, in early-stage serum samples. The combined diagnostic potential of the three miRNAs in advance-stage serum samples and early-stage serum samples has AUC values of 95.9 (95% CI: 0.925-1.012; sensitivity = 96.6% and specificity = 80.0%) and 98.1 (95% CI: 0.941-1.021; sensitivity = 90.5% and specificity = 100%), respectively.

Conclusion

Our data correlate the epigenetic deregulation of the miRNA genes with their expression. In addition, the miRNA panel (miR-205 + miR-200c + miR-141) has a much higher AUC, sensitivity, and specificity to predict EOC at an early stage in both tissue and serum samples.

HOTTIP-miR-205-ZEB2 Axis Confers Cisplatin Resistance to Ovarian Cancer Cells

Ovarian cancer is a deadly gynecological malignancy with resistance to cisplatin a major clinical problem. We evaluated a role of long non-coding (lnc) RNA HOTTIP (HOXA transcript at the distal tip) in the cisplatin resistance of ovarian cancer cells, using paired cisplatin sensitive and resistant A2780 cells along with the SK-OV-3 cells. HOTTIP was significantly elevated in cisplatin resistant cells and its silencing reversed the cisplatin resistance of resistant cells. HOTTIP was found to sponge miR-205 and therefore HOTTIP silenced cells had higher levels of miR-205. Downregulation of miR-205 could attenuate HOTTIP-silencing effects whereas miR-205 upregulation in resistant cells was found to re-sensitize cells to cisplatin. HOTTIP silencing also led to reduced NF-κB activation, clonogenic potential and the reduced expression of stem cell markers SOX2, OCT4, and NANOG, an effect that could be attenuated by miR-205. Finally, ZEB2 was identified as the gene target of miR-205, thus completing the elucidation of HOTTIP-miR-205-ZEB2 as the novel axis which is functionally involved in the determination of cisplatin resistance in ovarian cancer cells.

Vof16-miR-205-Gnb3 axis regulates hippocampal neuron functions in cognitively impaired diabetic rats

Background

Diabetes is a chronic metabolic disease and an independent risk factor for cognitive damage. Non-protein coding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are involved in various pathophysiological conditions.

Methods

In this study, cognitive impairment was induced in diabetics rats by streptozotocin (STZ) injection, and the differential lncRNAs and mRNAs in rat hippocampal tissue between control and STZ-treated groups were analyzed with microarray.

Results

In the hippocampus of STZ-treated diabetic rats, lncRNA Vof-16, and Gnb3 mRNA were significantly upregulated and silicon analysis showed that Vof-16 and miR-205 share the same miRNA response element (MRE). In addition, the overexpression of Vof-16 in primary hippocampal neurons inhibited the expression of miR-205, and vice versa. Dual luciferase assay verified the binding between Vof-16 and miR-205, and Vof-16 was seen to promote the proliferation of primary hippocampal neurons via sponging miR-205. Silicon analysis predicted that miR-205 could bind with Gnb3, which was verified with dual luciferase assay, and the overexpression of miR-205 could inhibit the protein level of Gnb3, which could be rescued by co-expression with Vof-16. In conclusion, lncRNA Vof-16 regulated Gnb3 expression by competitively binding to miR-205.

Conclusions

These results provided a novel regulation axis for the pathogenesis of STZ-induced diabetes.

Inhibition Sequence of miR-205 Hinders the Cell Proliferation and Migration of Lung Cancer Cells by Regulating PETN-Mediated PI3K/AKT Signal Pathway

The aim of this study was to identify the pro-tumor role of miR-205 in patients with lung cancer (LC) on the cell proliferation and migration through regulating PTEN-mediated PI3K/AKT signal pathway. Paired cancer tissues and adjacent tissues were collected from 107 LC patients who received treatment in Jinan Central hospital. In addition, the purchased LC cell lines were transfected into HCC827 cell line to observe and compare the biological behaviors. Compared with adjacent tissues, miR-205 was statistically higher in LC tissues, while PTEN was notably lower (P < 0.05). Inhibition of miR-205 not only suppressed cell proliferation, migration and invasion, increased apoptosis rate, but regulated epithelial mesenchymal transformation (EMT)-related proteins. Likewise, overexpression of PETN played the same role as that of miR-205 inhibition sequence. Inhibited miR-205 or PTEN overexpression brought dramatically decreased PI3K and p-Akt. The relationship between miR-205 and PTEN was verified through the biological prediction website and luciferase reporter. Co-transfection experiments revealed that after cotransfection of miR-205 inhibitor and si-PETN, the cell proliferation and invasion showed no marked difference between cotransfection group and NC group. MiR-205 is involved in LC cell proliferation and migration by regulating PETN-mediated PI3K/AKT signal pathway, which may be a feasible treatment target for LC in clinical practice.

The diagnostic value of miR-145 and miR-205 in patients with cervical cancer

OBJECTIVE

To investigate the diagnostic value of miRNA-145 (miR-145) and miRNA-205 (miR-205) in cervical cancer patients.

METHODS

Cervical tissue samples were collected from 144 patients diagnosed with and suspected to have cervical cancer in our hospital. Confirmed by pathology, 84 samples were obtained from cervical cancer patients and 60 samples were from patients with cervical intraepithelial neoplasia. Meanwhile, 30 patients with cervicitis were also selected, and the expression levels of miR-145, miR-205 and human papillomavirus (HPV) were detected in cervical lesions and normal cervical tissue.

RESULTS

In comparison to normal cervical tissue, cervicitis and cervical intraepithelial neoplasia groups, the relative expression level of miR-145 was significantly lower, whereas the relative expression level of miR-205 was notably higher in the cervical cancer group, respectively (P<0.001). The area under the receiver operating characteristic (ROC) curve of miR-145 for diagnosis of cervical cancer in patients was 0.878, of which the sensitivity and the specificity were 0.905 and 0.822, respectively. The area under the ROC curve of miR-205 was 0.881, of which the sensitivity and the specificity was 0.869 and 0.889, respectively. Among all patients, the relative expression level of miR-145 was significantly lower while the relative expression level of miR-205 was considerably higher in HPV-positive patients than those of HPV-negative groups (P<0.001). Parauterine invasion, FIGO stage III-IV and lymphatic metastasis were considered as independent factors that affect the expression of miR-145. FIGO stage III-IV and lymphatic metastasis were independent factors affecting the expression of miR-205.

CONCLUSION

The low expression level of miR-145 and the high expression level of miR-205 in patients with cervical cancer demonstrate a certain diagnostic value in cervical cancer. The expression level of miR-145 and miR-205 is correlated with HPV infection and cervical tumor malignancy.

Identification of a novel six autophagy-related genes signature for the prognostic and a miRNA-related autophagy predictor for anti-PD-1 therapy responses in prostate cancer

Background

Autophagy is a highly conserved homeostatic process in the human body that is responsible for the elimination of aggregated proteins and damaged organelles. Several autophagy-related genes (ARGs) contribute to the process of tumorigenesis and metastasis of prostate cancer (PCa). Also, miRNAs have been proven to modulate autophagy by targeting some ARGs. However, their potential role in PCa still remains unclear.

Methods

An univariate Cox proportional regression model was used to identify 17 ARGs associated with the overall survival (OS) of PCa. Then, a multivariate Cox proportional regression model was used to construct a 6 autophagy-related prognostic genes signature. Patients were divided into low-risk group and high-risk group using the median risk score as a cutoff value. High-risk patients had shorter OS than low-risk patients. Furthermore, the signature was validated by ROC curves. Regarding mRNA and miRNA, 12 differentially expressed miRNAs (DEMs) and 1073 differentially expressed genes (DEGs) were detected via the GEO database. We found that miR-205, one of the DEMs, was negatively regulated the expression of ARG (NKX2–3). Based on STRING analysis results, we found that the NKX2–3 was moderately related to the part of genes among the 6 autophagy-related genes prognostic signature. Further, NKX 2–3 was significantly correlated with OS and some clinical parameters of PCa by cBioProtal. By gene set enrichment analysis (GSEA). Lastly, we demonstrated that the association between NKX2–3 and tumor mutation burden (TMB) and PDCD1 (programmed cell death 1) of PCa.

Results

We identified that the six ARGs expression patterns are independent predictors of OS in PCa patients. Furthermore, our results suggest that ARGs and miRNAs are inter-related. MiR-205 was negatively regulated the expression of ARG (NKX2–3). Further analysis demonstrated that NKX2–3 may be a potential biomarker for predicting the efficacy of anti-PD-1 therapy in PCa.

Conclusions

The current study may offer a novel autophagy-related prognostic signature and may identify a promising miRNA-ARG pathway for predicting the efficacy of anti-PD-1 therapy in PCa.

Downregulation of miRNA-205 Expression and Biological Mechanism in Prostate Cancer Tumorigenesis and Bone Metastasis

Background

The expression and mechanism of microRNA-205 (miRNA-205) in prostate cancer (PCa) and its bone metastasis remain controversial.

Materials and Methods

The expression and discriminating capability of miRNA-205 were assessed by drawing a forest plot and a summarized receiver operating characteristic (SROC) curve, using data available from 27 miRNA-array and miRNA-sequencing datasets. The miRNA-205 target genes were acquired from online prediction tools, differentially upregulated genes in PCa, and differentially expressed genes (DEGs) after miRNA-205 transfection into PCa cell lines. Functional enrichment analysis was conducted to explore the biological mechanism of miRNA-205 targets. Immunohistochemistry (IHC) was applied to verify the protein level of the hub gene.

Results

The expression of miRNA-205 in the PCa group (1,461 samples) was significantly lower than that in the noncancer group (510 samples), and the downregulation of miRNA-205 showed excellent sensitivity and specificity in differentiating between the two groups. In bone metastatic PCa, the miRNA-205 level was further reduced than in nonbone metastatic PCa, and it showed a good capability in distinguishing between the two groups. In total, 153 miRNA-205 targets were screened through the three aforementioned methods. Based on the results of functional enrichment analysis, the targets of miRNA-205 were mainly enriched during chromosome segregation and phospholipid-translocating ATPase activity and in the spindle microtubule and the p53 signaling pathway. CDK1 had the highest connectivity in the PPI network analysis and was screened as one of the hub genes. A statistically significant negative correlation between miRNA-205 and CDK1 was observed. The expression of CDK1 in PCa samples was pronouncedly upregulated in terms of both the mRNA level and the protein level when compared with noncancer samples.

Conclusion

miRNA-205 may play a vital role in PCa tumorigenesis and bone metastasis by targeting CDK1.

SOX2-Upregulated microRNA-30e Promotes the Progression of Esophageal Cancer via Regulation of the USP4/SMAD4/CK2 Axis

Esophageal cancer (EC) is a highly aggressive disease, and its progression involves a complex gene regulation network. Transcription factor SOX2 is amplified in various cancers including EC. A pathway involving SOX2 regulation of microRNAs (miRNAs) and their target genes has been previously revealed. This study aims to delineate the ability of SOX2 to influence the EC progression, with the involvement of miR-30e/USP4/SMAD4/CK2 axis. SOX2 expression was first examined in the clinical tissue samples from 30 EC patients. Effects of SOX2 on proliferation, migration, and invasion alongside tumorigenicity of transfected cells were examined by means of gain- and loss-of-function experiments. EC tissues and cells exhibited high expression of SOX2, miR-30e, and CK2 and poor expression of USP4 and SMAD4. Mechanistically, SOX2 was positively correlated with miR-30e and upregulated the expression of miR-30e. miR-30e specifically targeted USP4, which induced deubiquitination of SMAD4 and promoted its expression. Meanwhile, SMAD4 was enriched in the CK2 promoter region and thus inhibited its expression. SOX2 stimulated EC cell proliferative, invasive, and migratory capacities in vitro and tumor growth in vivo by regulating the miR-30e/USP4/SMAD4/CK2 axis. Collectively, our work reveals a novel SOX2-mediated regulatory network in EC that may be a viable target for EC treatment.

The Role of microRNAs in Epithelial Ovarian Cancer Metastasis

Epithelial ovarian cancer (EOC) is the deadliest gynecological cancer, and the major cause of death is mainly attributed to metastasis. MicroRNAs (miRNAs) are a group of small non-coding RNAs that exert important regulatory functions in many biological processes through their effects on regulating gene expression. In most cases, miRNAs interact with the 3′ UTRs of target mRNAs to induce their degradation and suppress their translation. Aberrant expression of miRNAs has been detected in EOC tumors and/or the biological fluids of EOC patients. Such dysregulation occurs as the result of alterations in DNA copy numbers, epigenetic regulation, and miRNA biogenesis. Many studies have demonstrated that miRNAs can promote or suppress events related to EOC metastasis, such as cell migration, invasion, epithelial-to-mesenchymal transition, and interaction with the tumor microenvironment. In this review, we provide a brief overview of miRNA biogenesis and highlight some key events and regulations related to EOC metastasis. We summarize current knowledge on how miRNAs are dysregulated, focusing on those that have been reported to regulate metastasis. Furthermore, we discuss the role of miRNAs in promoting and inhibiting EOC metastasis. Finally, we point out some limitations of current findings and suggest future research directions in the field.

Circulating and Tissue microRNAs as Biomarkers for Ovarian Cancer Prognosis

Ovarian cancer (OC) is one of the most common cancers globally with a high rate of cancer- associated mortality. OC may be classified into epithelial cell neoplasms, germ cell neoplasms and stromal cell neoplasms. The five-year survival in the early and advanced stages of disease is approximately 90% and 15%, respectively. microRNAs are short, single-stranded, non-coding ribonucleic acid (RNA). miRNAs play critical roles in post transcriptionally regulations of gene expression. miRNAs are found in different tissues and body fluids. In carcinogenesis the expression of miRNAs are altered. Recent studies have revealed that there is a relationship between alteration of miRNAs expression and the prognosis of patients with OC. The aim of this review was to summarize the findings of recent studies that have investigated the expression of circulating and tissue miRNAs as novel biomarkers in the prognosis of OC.

miR-205: A Potential Biomedicine for Cancer Therapy

microRNAs (miRNAs) are a class of small non-coding RNAs that regulate the expression of their target mRNAs post transcriptionally. miRNAs are known to regulate not just a gene but the whole gene network (signaling pathways). Accumulating evidence(s) suggests that miRNAs can work either as oncogenes or tumor suppressors, but some miRNAs have a dual nature since they can act as both. miRNA 205 (miR-205) is one such highly conserved miRNA that can act as both, oncomiRNA and tumor suppressor. However, most reports confirm its emerging role as a tumor suppressor in many cancers. This review focuses on the downregulated expression of miR-205 and discusses its dysregulation in breast, prostate, skin, liver, gliomas, pancreatic, colorectal and renal cancers. This review also confers its role in tumor initiation, progression, cell proliferation, epithelial to mesenchymal transition, and tumor metastasis. Restoration of miR-205 makes cells more sensitive to drug treatments and mitigates drug resistance. Additionally, the importance of miR-205 in chemosensitization and its utilization as potential biomedicine and nanotherapy is described. Together, this review research article sheds a light on its application as a diagnostic and therapeutic marker, and as a biomedicine in cancer.

LncRNA SNHG17 aggravated prostate cancer progression through regulating its homolog SNORA71B via a positive feedback loop

Prostate cancer (PC) is a prevalent male malignancy with high occurrence rate. Recent studies have showed that small nucleolar host genes (SNHGs) and their homolog small nucleolar RNAs (snoRNAs) elicit regulatory functions in carcinogenesis. Present study aimed to investigate the role of SNHG17 and its homolog SNORA71B in PC. Function of SNHG17 and SNORA71B in PC is detected by CCK-8, colony formation, flow cytometry analysis of apoptosis, and transwell migration assay. The mechanism whereby SNHG17 regulated SNORA71B was detected by RIP, pulldown, ChIP, and luciferase reporter assays. Results depicted that transcript 6 of SNHG17 and SNORA71B were upregulated in PC. Knockdown of SNHG17 or SNORA71B weakened proliferation, invasion, migration, and epithelial-to-mesenchymal transition (EMT) and strengthened apoptosis. Mechanistically, SNHG17 and SNORA71B were transcriptionally activated by signal transducer and activator of transcription 5A (STAT5A). SNHG17 positively regulated SNORA71B in PC cell lines and other cell lines. SNHG17 sponged miR-339-5p to upregulate STAT5A and therefore to cause transactivation of SNORA71B. Rescue experiments delineated that SNORA71B was required for the regulation of SNHG17 on PC. Moreover, SNHG17 silence hindered tumorigenesis of PC in vivo. In conclusion, current study first revealed that lncRNA SNHG17 aggravated prostate cancer progression through regulating its homolog SNORA71B via a positive feedback loop, which might do help to the pursuit of better PC treatment.

Advantages of Restoring miR-205-3p Expression for Better Prognosis of Gastric Cancer via Prevention of Epithelial-mesenchymal Transition

Purpose

miR-205 is a tumor suppressor and plays an important role in tumor invasiveness. However, the role of miR-205 in human gastric cancer (GC) epithelial-mesenchymal transition (EMT) remains unclear. The aim of this study was to investigate the molecular mechanism of miR-205 in the regulation of EMT in GC invasion.

Materials and Methods

Quantitative polymerase chain reaction (qPCR) was used to detect the expression of miR-205 in GC. Further, the correlation between the pathological parameters and prognosis of GC was statistically analyzed. A transwell model was used to evaluate the effect of miR-205-3p on the invasion and migration of GC cells. qPCR, western blotting, and luciferase assay were performed to analyze the relationship and target effects between miR-205-3p and the expression of zinc finger electron box binding homologous box 1 (ZEB1) and 2 (ZEB2).

Results

We found that the levels of miR-205-3p were significantly lower (P<0.05) in GC tissues than in matched normal tissues. Additionally, the expression of miR-205-3p was related to the tumor invasion depth, lymph node metastasis, lymph node invasion, and tumor, node, metastasis stage. Patients with lower miR-205-3p expression levels in the tumors had a poorer prognosis. The in vitro assays indicated that miR-205-3p could affect the invasion ability and EMT of GC cells by targeting the expression of both ZEB1 and ZEB2.

Conclusions

miR-205-3p promotes GC progression and affects the prognosis of patients by targeting both ZEB1 and ZEB2 to directly influence EMT.

Smad4 induces cell death in HO-8910 and SKOV3 ovarian carcinoma cell lines via PI3K-mTOR involvement

IMPACT STATEMENT

This study investigated the effect and mechanism of Smad4 in ovarian carcinoma (OC) cell viability and demonstrated that Smad4 acted as a tumor suppressor in OC, which may contribute to the understanding of molecular mechanisms underlying OC occurrence and progression. Smad4 expression was decreased in the OC specimens, but Smad4 recovery in the OC cell lines impaired the survival and viability of OC cells by increasing autophagy and apoptosis. Further investigation showed that Smad4 interacted with the P85 subunit of PI3K and caused deactivation of the PI3K/mTOR pathway. Therefore, Smad4 could be considered as a target in cancer therapy due to its regulatory effect in OC carcinogenesis.

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.

Secondary Structural Model of Human MALAT1 Reveals Multiple Structure-Function Relationships

Human metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is an abundant nuclear-localized long noncoding RNA (lncRNA) that has significant roles in cancer. While the interacting partners and evolutionary sequence conservation of MALAT1 have been examined, much of the structure of MALAT1 is unknown. Here, we propose a hypothetical secondary structural model for 8425 nucleotides of human MALAT1 using three experimental datasets that probed RNA structures in vitro and in various human cell lines. Our model indicates that approximately half of human MALAT1 is structured, forming 194 helices, 13 pseudoknots, five structured tetraloops, nine structured internal loops, and 13 intramolecular long-range interactions that give rise to several multiway junctions. Evolutionary conservation and covariation analyses support 153 of 194 helices in 51 mammalian MALAT1 homologs and 42 of 194 helices in 53 vertebrate MALAT1 homologs, thereby identifying an evolutionarily conserved core that likely has important functional roles in mammals and vertebrates. Data mining revealed that RNA modifications, somatic cancer-associated mutations, and single-nucleotide polymorphisms may induce structural rearrangements that sequester or expose binding sites for several cancer-associated microRNAs. Our findings reveal new mechanistic leads into the roles of MALAT1 by identifying several intriguing structure–function relationships in which the dynamic structure of MALAT1 underlies its biological functions.

MiR-205 promotes endothelial progenitor cell angiogenesis and deep vein thrombosis recanalization and resolution by targeting PTEN to regulate Akt/autophagy pathway and MMP2 expression

MicroRNAs (MiRNAs, MiRs) represent a class of conserved small non-coding RNAs that affect post-transcriptional gene regulation and play a vital role in angiogenesis, proliferation, apoptosis, migration and invasion. They are essential for a wide range of physiological and pathological processes, especially for vascular diseases. However, data concerning miRNAs in endothelial progenitor cells (EPCs) and deep vein thrombosis (DVT) remain incomplete. We explored miRNAs that modulate angiogenesis in EPCs and thrombolysis, and analysed their underlying mechanisms using a DVT model, dual-luciferase reporter assay, qRT-PCR, Western blot, immunofluorescence staining, flow cytometry analysis, CCK-8 assay, angiogenesis assay, wound healing and Transwell assay. We found that miR-205 enhanced the homing ability of EPCs to DVT sites and promoted thrombosis resolution and recanalization, which significantly reduced venous thrombus. Additionally, we demonstrated that miR-205 overexpression significantly enhanced angiogenesis in vivo and in vitro, migration, invasion, F-actin filaments and proliferation in EPCs, and inhibited cell apoptosis. Conversely, down-regulation of miR-205 played the opposite role in EPCs. Importantly, this study demonstrated that miR-205 directly targeted PTEN to modulate the Akt/autophagy pathway and MMP2 expression, subsequently playing a key role in EPC function and DVT recanalization and resolution. These results elucidated the pro-angiogenesis effects of miR-205 in EPCs and established it as a potential target for DVT treatment.

Everolimus inhibits the proliferation and migration of epidermal growth factor receptor-resistant lung cancer cells A549 via regulating the microRNA-4328/phosphatase and tensin homolog signaling pathway

Lung cancer is the most common cancer type worldwide, and investigating novel therapeutics methods for the treatment of chemoresistant lung cancer are of notable clinical significance. Reverse transcription-quantitative polymerase chain reaction and western blotting assays were performed to analyze the expression levels of phosphatase and tensin homolog (PTEN) and microRNA-4328 (miR-4328), and Cell Counting Kit-8 (CCK-8) and Transwell migration assays were conducted to evaluate the proliferation and migration of A549 cells, respectively. Everolimus was observed to upregulate the expression of PTEN and inhibit the proliferation and migration of A549 cells in a dose-dependent manner. The knockdown of PTEN abolished the effects of everolimus on the proliferation and migration of A549 cells, and everolimus was demonstrated to upregulate PTEN, and inhibit the proliferation and migration of A549 cells via downregulating miR-4328. Collectively, the results of the present study indicate that everolimus inhibited the proliferation and migration of EGFR-resistant A549 lung cancer cells via regulating the miR-4328/PTEN signaling pathway.

Upregulation of Long Noncoding RNA GAS5 Inhibits Lung Cancer Cell Proliferation and Metastasis via miR-205/PTEN Axis

Background

Long noncoding RNA (lncRNA) is a key part of noncoding RNA class and increasing evidences have manifested that it plays a significant role in the physiology and pathology. The growth arrest-specific transcript 5 (GAS5) is a vital tumor suppressor in some types of cancers. However, the function of GAS5 in lung cancer remains largely no clear. The purpose of the current study was to identify the biological role of GAS5 in non-small cell lung cancer (NSCLC).

Material/Methods

To study the role of GAS5 in the NSCLC, the RT-PCR, Western Blot, Luciferase assay, and RNA immunoprecipitation assay was employed to determine the relationship of GAS5, miR-205, and PTEN. CCK8 assay, Cell migration and invasion assay was used for the role of GAS5 in lung cancer cell proliferation and metastasis.

Results

The results indicated that GAS5 was drastically downregulated in lung cancer cell lines. Further functional analysis showed that down-expression of GAS5 remarkably induced NSCLC growth, migration, and invasion. The luciferase reporter assays determined that miR-205 was a direct target of GAS5 in lung cancer. Moreover, the Phosphatase and tensin homologue (PTEN) was known as a direct target of miR-205 and miR-205/PTEN rescued the effects of GAS5 in NSCLC cells.

Conclusions

To sum up, our results illustrate that upregulation of GAS5 in NSCLC suppresses its growth, migration, and invasion via the miR-205/PTEN axis.

Upregulation of miR-146a-5p is associated with increased proliferation and migration of vascular smooth muscle cells in aortic dissection

BACKGROUND

This study aimed to investigate whether miR-146a-5p was involved in the pathogenesis of thoracic aortic dissection (AD) via regulating the biological function of vascular smooth muscle cells (VSMCs).

METHODS

Circulating miR-146a-5p level was measured by quantitative polymerase chain reaction (qPCR) in AD patients and healthy controls. Human dissected aortic samples were obtained from patients with thoracic AD Stanford type A undergoing surgical repair, and normal control samples were from organ donors who died from nonvascular diseases. The expression level of miR-146a-5p was detected using qPCR in each sample. The expression of SMAD4, which is involved in the TGF-β pathway and indicated as the target gene of miR-146a-5p, was measured by qPCR and Western blot analysis at the mRNA level and protein level, respectively. Subsequently, VSMCs were transfected with miR-146a-5p mimics or inhibitors in vitro. VSMC proliferation and migration were detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assay, respectively. Flow cytometry was used to identify apoptosis. The expression of SMAD4 in VSMCs was determined using qPCR and Western blot analysis.

RESULTS

Plasma level of miR-146a-5p is significantly higher in the AD group as compared with the control group. The expression of miR-146a-5p was significantly upregulated in dissected aorta compared with controls (P < 0.05). The overexpression of miR-146a-5p significantly induced VSMC proliferation and migration in vitro.

CONCLUSIONS

The expression of SMAD4 was modulated by miR-146a-5p. miR-146a-5p induced VSMC proliferation and migration through targeting SMAD4 and hence might be potentially involved in the development of AD.

MicroRNA-20b promotes proliferation of H22 hepatocellular carcinoma cells by targeting PTEN

MicroRNAs (miRNAs/miRs) are small, noncoding RNA molecules that are closely associated with the occurrence and development of tumors. miR-20b is overexpressed in hepatocellular carcinoma cell lines and tissues. However, it is not clear whether miR-20b can promote the proliferation of hepatocellular carcinoma cells. In the present study, the proliferation of H22 mouse hepatocellular carcinoma cells was detected using the Cell Counting Kit-8 assay. MiRanda software was used to predict the binding sites of miR-20b to the 3'-untranslated region (3'-UTR) of phosphatase and tensin homolog (PTEN). The 3'-UTR sequence of the PTEN gene was amplified using the polymerase chain reaction in H22 cells. The recombinant plasmid or empty plasmid was co-transfected with miR-20b mimics or miR-20b scramble into HeLa cells, and luciferase activity was assessed by Dual-Luciferase^® Reporter Assay System 24 h post-transfection. In the present study, miR-20b knockdown significantly inhibited the proliferation of H22 mouse hepatocellular carcinoma cells. In addition, miR-20b inhibition upregulated the expression of PTEN, and it was revealed that miR-20b may directly target the 3'-untranslated region of the PTEN gene. Downregulation of PTEN partially reversed the anti-proliferative effect of miR-20b on H22 cells. In conclusion, miR-20b may promote H22 cell proliferation by targeting PTEN, providing a rationale for further study investigating novel therapeutic strategies for liver cancer.

miR-205-5p Mediated Downregulation of PTEN Contributes to Cisplatin Resistance in C13K Human Ovarian Cancer Cells

Cisplatin resistance is a major cause of treatment failure in advanced ovarian cancer. The limited evidence shows the paradoxical regulation of miR-205 on chemotherapy resistance in cancer. Herein, we found that miR-205-5p was enormously increased in cisplatin-resistant C13K ovarian cancer cells compared with its cisplatin-sensitive OV2008 parental cells using miRNA microarrays, which was further verified by quantitative PCR. Furthermore, we confirmed that inhibition of miR-205-5p upregulated PTEN and subsequently attenuated its downstream target p-AKT, which inversed C13K cells from cisplatin resistance to sensitivity. Our data suggest that miR-205-5p contributes to cisplatin resistance in C13K ovarian cancer cells may via targeting PTEN/AKT pathway.