MicroRNA

High Expression of miR-483-5p Predicts Chemotherapy Resistance in Epithelial Ovarian Cancer

Background: Ovarian cancer is the most deadly cancer that requires novel diagnostics and therapeutics. MicroRNAs are viewed as essential gene regulatory elements involved in different pathobiological mechanisms of many cancers, including ovarian cancer. Objective: This study examined the relationship between microRNA (miRNA) expression and response to platinum-based chemotherapy. Methods: Genome-wide miRNA expression analysis was conducted using Epithelial Ovarian Cancer (EOC) tissues from 25 patients with 17 malignant tumors and eight benign ovarian tumors. Candidate miRNAs that respond to platinum-based chemotherapy were selected for validation by quantitative RT-PCR. Result: Among 2,578 mature human miRNAs, high expression of miR-483-5p correlated with poor responses to platinum-based chemotherapy in EOC patients. Furthermore, high levels of miR-483-5p in the resistant group suppressed expression of the apoptotic regulator TAOK-1. Conclusion: A possible marker for the prediction of chemotherapy response and resistance in patients may be miR-483-5p. Choosing the right treatment for each patient with EOC can avoid the risk of developing chemotherapy resistance.

MicroRNA Expression Profiling of Epithelial Ovarian Cancer Identifies New Markers of Tumor Subtype

Background: Epithelial Ovarian Cancer (EOC) is often challenging to diagnose, even though histological examination. MicroRNA (miRNA or miRNA) is bound to the target messenger RNA (mRNA) due to which the mRNA molecules are silenced. The identification of miRNA expression- based EOC subtypes is considered a critical means of prognostication. So far, the studies on EOC subtypes have not been well characterized. Objective: This study aimed to confirm the existence of miRNAs in EOC and to assess their potential as clinical biomarkers for EOC. Methods: We sampled 25 ovarian tumor tissues from patients with human ovarian tumors (17 malignant; 12 serous EOC, five non-serous EOC, and eight benign ovarian tumors). miRNA microarray detection was performed to identify EOC miRNAs. Real-time PCR was adapted for the validation of differentially expressed miRNAs detected by microarray analysis related to hybridization intensity. Results: The results confirmed that miRNAs exist in EOC, relative expression of EOC miRNAs demonstrated that the upregulation of miR-483-5p, and downregulation of miR-127-3p, and miR- 532-5p were significantly expressed in the malignant group than in the benign group at p < 0.05. Besides, miR-483-5p could also distinguish EOC subtypes between serous EOC and non-serous EOC, with a p < 0.05. Conclusion: A comprehensive miRNA expression profiling can help to refine subtype classification in EOC, opening new opportunities for identifying clinically applicable markers for improved stratification and diagnostics of ovarian tumors.

The Promising Signatures of Circulating microRNA-145 in Epithelial Ovarian Cancer Patients

Background:Epithelial ovarian cancer continues to be a deleterious threat to women as it is asymptomatic and is typically detected in advanced stages. Cogent non-invasive biomarkers are therefore needed which are effective in apprehending the disease in early stages. Recently, miRNA deregulation has shown a promising magnitude in ovarian cancer tumorigenesis. miRNA-145(miR- 145) is beginning to be understood for its possible role in cancer development and progression. In this study, we identified the clinicopathological hallmarks altered owing to the downexpression of serum miR-145 in EOC.Methods:70 serum samples from histopathologically confirmed EOC patients and 70 controls were collected. Total RNA from serum was isolated by Trizol method, polyadenylated and reverse transcribed into cDNA. Expression level of miR-145 was detected by miRNA qRT-PCR using RNU6B snRNA as reference.Results:The alliance of miR-145 profiling amongst patients and controls established itself to be conspicuous with a significant p-value (p<0.0001). A positive conglomeration (p=0.04) of miR-145 profiling was manifested with histopathological grade. Receiver Operating Characteristic (ROC) curve highlights the diagnostic potential and makes it imminent with a robust Area Under the curve (AUC). A positive correlation with the ROC curve was also noted for histological grade, FIGO stage, distant metastasis, lymph node status and survival.Conclusion:Our results propose that miR-145 down-regulation might be a possible touchstone for disease progression and be identified as a diagnostic marker and predict disease outcome in EOC patients.

MicroRNA Levels in Cervical Cancer Samples and Relationship with Lesion Grade and HPV Infection

Background: miR-21, miR-214 and miR-let-7a are three validated and well-known miRNAs. miR-21 is described as an “oncomir” while miR-214 and miR-let-7a are described mainly as tumor suppressors. The role of these miRNAs remains unclear in cervical cancer, an important malignancy among women worldwide and responsible for many deaths every year. Objective: The objective of this study is to describe the expression profile of miR-21, miR-214 and miR-let-7a in plasma and in cervical scraping from a control group and patients with different grades of cervical lesions and invasive cervical cancer and correlate with HPV infection groups. Methods: Plasma and cervical scraping were submitted to DNA and RNA extraction. HPV detection and typing were performed by conventional PCR followed by PAGE to amplicons interpretation. The miRNA relative expression in plasma and cervical scraping samples was performed by real time PCR using specific TaqMan probes. Results: miR-21 (p=0.0277) and miR-214 (p=0.0151) were up-regulated in cervical scraping samples of invasive cervical cancer (ICC) group. However, miR-214 was also up-regulated in the LSIL group (p=0.0062). Both miRNAs were not related to HPV infection. However, miR-let-7a was higher in HPV positive plasma samples (p=0.0433) than in HPV negative plasma samples and the correlation analysis confirmed the association between the levels of this miRNA with the presence of HPV (p=0.0407; r=0.3029), but not with lesion grade (p>0.05). Conclusion: Our results suggest that miR-21 is related to cervical cancer progression and miR-214 appears to have an ambiguous role in cervical lesions. miR-let-7a may be upregulated at a systemic level in patients with HPV infection.

Genetic Polymorphism of miR-218-2 (rs11134527) in Cervical Cancer: A Case-Control Study on the Bangladeshi Women

Background: The prevalence of Cervical Cancer (CC) is disproportionately higher in developing countries. It is the second most frequent cancer type among Bangladeshi women and the major cause of morbidity and mortality. However, no previous data reported the association of miR-218-2 gene polymorphisms in Bangladeshi cervical cancer patients. Aim: This case-control study was designed to find the link between the rs11134527 polymorphism in miR-218-2 and CC. Methods: A total of 488 subjects were recruited, comprising 256 cervical cancer patients and 232 healthy females. Genotyping was conducted with the tetra-primer ARMS-PCR technique to detect the association. Results: The results of genotype data showed that rs11134527 was in the Hardy-Weinberg equilibrium in both CC cases and controls (P >0.05). Overall, the polymorphism was found to be significantly associated with an increased risk of cervical cancer with AG genotype (AG vs. GG: OR = 2.26, 95% Cl = 1.40-3.66, P = 0.0008), AA genotype (AA vs. GG: OR = 3.64, 95% Cl = 2.17-6.10, P <0.0001), dominant model (AG+AA vs. GG: OR = 2.75, 95% Cl = 1.75-4.31, P <0.0001), recessive model (AA vs. GG+AG: OR = 2.08, 95% Cl = 1.41-3.08, P = 0.0002), and A allele (A vs. G: OR = 1.94, 95% Cl = 1.51-2.51, P <0.0001). All of these correlations remained statistically significant after performing Bonferroni correction (P <0.008). Conclusion: Our study suggests that the rs11134527 polymorphism in the miR-218-2 gene contributes to the susceptibility of CC in Bangladeshi women.

Diagnostic Value of MicroRNA 21 in Endometrial Cancer and Benign Lesions and its Differential Expression with Clinicopathological Parameters

Background: Endometrial cancer is one of the most common malignancies among women worldwide. Although this cancer is often diagnosed at early stages, the need for biomarkers of diagnosis remains a necessity to overcome conventional invasive procedures of diagnosis. Objective: In our study, we aim to investigate the diagnostic value of microRNA-21 in endometrial cancer and its relation to clinicopathological features. Methods: We used RT-qPCR to measure the expression of microRNA-21 in 71 tumor tissues, 53 adjacent tissues, and 54 benign lesions. Results: Our results show that microRNA-21 is a potential biomarker for endometrial cancer with an area under the receiver operating characteristic curve of 0.925 (95% CI = 0.863 - 0.964, P<0.0001). The sensitivity was 84.51% (95% CI = 74.0 - 92.0) and specificity was 86.79% (95% CI = 74.7 - 94.5). For discrimination between benign lesions and controls the AUC was 0,881 with a sensitivity of 100% (95% CI = 93.4 - 100.0) and specificity of 66.04% (95% CI = 51.7 - 78.5), and for discriminating benign lesions from tumors the AUC was 0,750 with a sensitivity of 54.93% (95% CI = 42.7 - 66.8) and specificity of 90.74% (95% CI = 79.7 - 96.9). We also found that tumors with elevated microRNA-21 expression are of advanced FIGO stage, high histological grades, and have cervical invasion, myometrial invasion and distant metastasis. Conclusion: Our findings support the important role of miR-21 as a biomarker to diagnose endometrial cancer. Further studies on minimally invasive/noninvasive samples such as serum, blood, and urine are necessary to provide a better alternative to current diagnosis methods.

Tumor Targeting via siRNA-COG3 to Suppress Tumor Progression in Mice and Inhibit Cancer Metastasis and Angiogenesis in Ovarian Cancer Cell Lines

Background: The COG complex is implicated in the tethering of retrograde intra-Golgi vesicles, which involves vesicular tethering and SNAREs. SNARE complexes mediate the inva-sion and metastasis of cancer cells through MMPs which activate growth factors for ECM frag-ments by binding to integrin receptors. Increasing MMPs is in line with YKL40 since YKL40 is linked to promoting angiogenesis through VEGF and can increase ovarian cancer (OC) resistance to chemotropic and cell migration. Objective: The aim of this study is an assessment of siRNA-COG3 on proliferation, invasion, and apoptosis of OC cells. In addition, siRNA-COG3 may prevent the growth of OC cancer in mice with tumors. Methods: Primary OC cell lines will be treated with siRNA-COG3 to assay YKL40 and identified angiogenesis by Tube-like structure formation in HOMECs. The Golgi morphology was analyzed using Immunofluorescence microscopy. Furthermore, the effects of siRNA-COG3 on the prolifer-ation and apoptosis of cells were evaluated using MTT and TUNEL assays. Clones of the HOSEpiC OC cell line were subcutaneously implanted in FVB/N mice. Mice were treated after two weeks of injection of cells using siRNA-COG3. Tumor development suppression was detected by D-luciferin. RT-PCR and western blotting analyses were applied to determine COG3, MT1-MMP, SNAP23, and YKL40 expression to investigate the effects of COG3 gene knockdown. Results: siRNA-COG3 exhibited a substantial effect in suppressing tumor growth in mice. It dra-matically reduced OC cell proliferation and triggered apoptosis (all p < 0.01). Inhibition of COG3, YKL-40, and MT1-MPP led to suppression of angiogenesis and reduction of microvessel density through SNAP23 in OC cells. Conclusion: Overall, by knockdown of the COG3 gene, MT1-MMP and YKL40 were dropped, leading to suppressed angiogenesis along with decreasing migration and proliferation. SiRNA-COG3 may be an ideal agent to consider for clinical trial assessment therapy for OC, especially when an antiangiogenic SNAR-pathway targeting drug.

A Systematic Review and Bioinformatics Study on Genes and micro-RNAs Involving the Transformation of Endometriosis into Ovarian Cancer

Background: Along with the description of tumorigenesis processes in endometriosisrelated ovarian cancer, identifying dysregulated miRNAs, the target genes of these miRNAs, and the processes abnormally affected by dysregulated miRNAs is essential, which was our goal. Methods: Two reviewers individually evaluated the articles which collected relevant information including genes and miRNAs involved in the transformation of endometriosis into ovarian cancer. To assess the mature sequence of miRNAs and also their chromosomal positions, miRPathDB software was employed. To determine the main target gene predicted for each considered miRNAs, the TargetScanS Web server was applied. The interaction of each gene with other genes associated with endometrial- related ovarian cancer was determined by GeneMANIA software. Finally, to design integrated model of miRNAs-targeted genes interaction network, the Cytoscape software was used. Results: The final number of studies available for analysis was 6 manuscripts including 22 miRNAs described as involved in the transformation of endometriosis into different subtypes of ovarian cancers (14 miRNAs up-regulated and 8 miRNAs down-regulated). Three miRNAs of miR-141 (upregulated), miR-205 (down-regulated), and miR-125b (down-regulated) were revealed as the originator for genetic interactions leading to carcinogenesis. We could show some common loops and pathways including uncontrolled cell proliferation and abnormal apoptosis (mediated by PTEN gene induced by miR-21 and miR-214), and disaggregation and epithelialization (mediated by ZEB1 and ZEB2 genes induced by miR-200). Conclusions: According to our analysis, up-regulation of miR-141 and down-regulation of miR-205 and miR-125b have a central role in transforming endometriosis to ovarian cancer.

Human Papillomavirus Infections, Cervical Cancer and MicroRNAs: An Overview and Implications for Public Health

Human Papillomavirus (HPV) is among the most common sexually transmitted infections in both females and males across the world that generally do not cause symptoms and are characterized by high rates of clearance. Persistent infections due at least to twelve well-recognized High-Risk (HR) or oncogenic genotypes, although less frequent, can occur, leading to diseases and malignancies, principally cervical cancer. Three vaccination strategies are currently available for preventing certain HR HPVs-associated diseases, infections due to HPV6 and HPV11 low-risk types, as well as for providing cross-protection against non-vaccine genotypes. Nevertheless, the limited vaccine coverage hampers reducing the burden of HPV-related diseases globally. For HR HPV types, especially HPV16 and HPV18, the E6 and E7 oncoproteins are needed for cancer development. As for other tumors, even in cervical cancer, non-coding microRNAs (miRNAs) are involved in posttranscriptional regulation, resulting in aberrant expression profiles. In this study, we provide a summary of the epidemiological background for HPV occurrence and available immunization programs. In addition, we present an overview of the most relevant evidence of miRNAs deregulation in cervical cancer, underlining that targeting these biomolecules could lead to wide translational perspectives, allowing better diagnosis, prognosis and therapeutics, and with valuable applications in the field of prevention. The literature on this topic is rapidly growing, but advanced investigations are required to achieve more consistent findings on the up-regulated and down-regulated miRNAs in cervical carcinogenesis. Because the expression of miRNAs is heterogeneously reported, it may be valuable to assess factors and risks related to individual susceptibility.

miR-21 and miR29-a: Potential Molecular Biomarkers for HPV Genotypes and Cervical Cancer Detection

Background and objective: This study aimed to assess miR21 and miR-29a diagnostic usefulness for HPV infection and Cervical Cancer (CC) detection. Methods: miRs extraction has been performed on HPV-positive, CC and negative control of 43, 50 and 46 individuals, respectively. The expression level of miRs has been analyzed using Real-Time RT-PCR. Results: There was a correlation between the expression of miRs and the Receiver Operating Characteristic (ROC) analysis in CC and HPV-positive patients. Conclusion: The correlation between expressions of miRs is notable. ROC curve analysis could be applied in molecular diagnostic exposure for CC related to HPV infections.