miR-21 Gene Research Articles

Экспрессия микроРНК miR-9, miR-27a, miR-34a, miR-146a, miR-155 в сетчатке при развитии у крыс OXYS ретинопатии, аналогичной возрастной макулярной дегенерации

Возрастная макулярная дегенерации (ВМД) - комплексное нейродегенеративное заболевание, которое становится основной причиной потери центрального зрения людьми старше 60 лет. Развитие ВМД контролируется множеством взаимодействующих генетических и средовых факторов, определяющих форму, скорость прогрессии заболевания. Существенно влияют на эти параметры и эпигенетические механизмы, включая изменения паттернов экспрессии микроРНК, оценка циркулирующего пула которых рассматривается как перспективный подход к ранней диагностике, прогнозу течения и оценке эффективности лечения ВМД. Однако информация о паттернах экспрессии микроРНК в сетчатке на разных стадиях развития ВМД, тем более доклинических, практически отсутствует, а получить её позволяет только использование адекватных биологических моделей. Настоящее исследование выполнено на линии крыс OXYS (ИЦиГ СО РАН) - уникальной модели преждевременного старения, одним из проявлений которого становится развитие комплекса ключевых признаков ВМД. Его целью явилась оценка изменений экспрессии ряда перспективных с прогностической точки зрения микроРНК (miR-9, miR-27a, miR-34a miR-146a, miR-155) с возрастом в сетчатке крыс Вистар (контроль) и OXYS при развитии аналогичной ВМД ретинопатии. Экспрессию микроРНК оценивали методом ПЦР в реальном времени. Было выявлено увеличение уровня экспрессии miR-27a в сетчатке крыс OXYS с возрастом и по мере развития признаков ретинопатии, которое может вносить вклад в развитие признаков ВМД. Age-related macular degeneration (AMD) is a complex neurodegenerative disease that becomes the main cause of central vision loss in people over 60 years of age. The development of AMD is controlled by a variety of interacting genetic and environmental factors that determine the form and rate of progression of the disease. Epigenetic mechanisms also significantly affect these parameters, including changes in microRNA expression patterns, the assessment of the circulating pool of which is considered as a promising approach to early diagnosis, prognosis of the course and evaluation of the effectiveness of AMD treatment. However, there is practically no information about the patterns of microRNA expression in the retina at different stages of AMD development, especially preclinical ones, and it can only be obtained using adequate biological models. The present study was performed on a line of OXYS rats (ICG SB RAS) - a unique model of premature aging, one of the manifestations of which is the development of a complex of key signs of AMD. Its purpose was to evaluate changes in the expression of a number of prognostically promising microRNAs (miR-9, miR-27a, miR-34a, miR-146a, miR-155) with age in the retina of Wistar rats (control) and OXYS with the development of AMD-like retinopathy. microRNA expression was evaluated by real-time PCR An increase in the level of miR-27a expression in the retina of OXYS rats was revealed with age and with the development of signs of retinopathy, which may contribute to the development of signs of AMD.

Six miRNA expressions in the saliva of smokers and non-smokers with periodontal disease.

It has been stated that microRNA (miRNA) plays an important role in development, homeostasis, and immune functions, and abnormal miRNA expression may cause faster disease progression. The aim of this study was to determine miR-203, miR-142-3p, miR-146a, miR-146b, miR-155, and miR-29b gene expressions in the saliva of smokers and non-smokers with the periodontal disease before and after non-surgical periodontal therapy (NSPT). A total of 90 individuals, 30 with periodontitis, 30 with gingivitis, and 30 periodontally healthy (control group), were included. These three groups were divided into subgroups as smoking and non-smoking individuals, with 15 people in each group. NSPT was applied to patients with periodontitis and gingivitis. Saliva samples and clinical parameters were obtained at baseline and repeated 6 weeks after NSPT. Saliva miR-203, miR-142-3p, miR-146a, miR-146b, and miR-155 gene expressions were significantly upregulated in patients with periodontal disease compared to the control group both in smokers and non-smokers, and also these miRNAs' gene expressions were significantly higher in the periodontitis group than in the gingivitis group at baseline (p < .05). A significant increase in saliva miR-142-3p expression was detected in all groups of smokers compared to non-smokers (p < .05). Although there was a decrease in salivary miRNAs gene expressions with the treatment, it was not statistically significant (p > .05). These results suggest that salivary miR-146a, miR-146b, miR142-3p, miR-155, and miR-203 gene expressions increased with the progression of periodontal disease, but unchanged after periodontal treatment. Moreover, smoking may contribute to an increase in the levels of salivary miR-142-3p in the periodontal health and disease.

Changes in the Level of Methylation of a Group of microRNA Genes as a Factor in the Development and Progression of Non-Small Cell Lung Cancer.

We studied changes in the level of methylation of a number of microRNA genes hypermethylated in non-small cell lung cancer and its histological subtypes as well as the relationship of methylation of a group of microRNA genes with clinical and morphological features of the tumor with smoking status. A significantly high level of methylation of 7 genes (MIR124-1/3, MIR125B-1, MIR129-2, MIR137, MIR1258, and MIR339) was revealed in adenocarcinoma and squamous cell lung cancer in comparison with samples of adjacent histologically unchanged lung tissue. In squamous cell lung cancer, a significantly high level of methylation of the MIR124-2 gene in the tumor was also shown. In addition, differences in the methylation profile of adenocarcinoma and squamous cell carcinoma at stages III-IV of the oncological process were revealed. A high level of methylation of the MIR137 and MIR1258 genes was shown for adenocarcinoma and MIR339, MIR129-2, and MIR124-2 for squamous cell carcinoma. Significant differences in the level of methylation of MIR124-2 and MIR375 genes were revealed for smoking patients with squamous cell lung cancer.

LncRNA SNHG16 is Downregulated in Pneumonia and Downregulates miR-210 to Promote LPS-Induced Lung Cell Apoptosis.

Long non-coding RNA Small Nucleolar RNA Host Gene 16 (SNHG16) has been reported to participate in Lipopolysaccharide (LPS)-induced inflammatory pathway, which contributes to pneumonia. This study was therefore conducted to explore the role of SNHG16 in pneumonia. In this study, expression of SNHG16 and microRNA (miR)-210 in pneumonia plasma samples (n = 56) and control samples (n = 60) was detected by RT-qPCR. The potential crosstalk between SNHG16 and miR-210 was analyzed by performing overexpression experiments. MSP was performed to study the role of SNHG16 in methylation of miR-210 gene. Cell apoptosis was analyzed by cell apoptosis assay. Decreased expression levels of SNHG16 and increased expression levels of miR-210 were observed in pneumonia. SNHG16 showed an inverse correlation to miR-210. LPS treatment led to downregulated SNHG16 and upregulated miR-210 in Human Bronchial Epithelial Cells (HBEpCs). In HBEpCs, SNHG16 downregulated miR-210 and increased miR-210 DNA gene methylation. Moreover, SNHG16 suppressed the role of miR-210 in cell apoptosis under LPS treatment. In conclusion, SNHG16 is downregulated in pneumonia, and it downregulates miR-210 possibly through methylation to promote lung cell apoptosis induced by LPS.

Exponential and efficient target-catalyst rolling circle amplification for label-free and ultrasensitive fluorescent detection of miR-21 and p53 gene

MicroRNAs (miRNAs) and p53 gene can serve as valuable biomarkers for the diagnosis of a variety of cancers. Nevertheless, although the development of the DNA nanostructure on the detection of cancer-related biomarkers was initially demonstrated several years ago, the challenges of developing simpler, cheaper, and multi-level detection DNA biosensors persist. Herein, based on the rolling circle amplification (RCA) coupled with the target-triggered skill, we have developed a well-designed detecting platform. In this study, the dumbbell-shaped probes (DPP) could be cyclized and initiated through targets, thus beginning the target-catalyst RCA (tc-RCA) reaction, therefore engendering numerous dumbbell probe amplicons (DPA). Thereafter the probe primers (PP) mutually complementary to the loop of DPA was introduced, leading to the branch strand displacement reaction (B-SDA). SYBR Green I can effectively bind to the amplified double-stranded structures as a fluorescent reporter. Altering the target-binding sequence of the DPP, this biosensor can also be applied to detect different biomarkers. As a consequence, target miR-21 and p53 gene can be detected down to 0.65 fM and 2.04 fM respectively with a wide dynamic range. Moreover, we have also achieved the qualitative detection of interesting targets in cell lysates as well as the complex biological substrates and compared the results with reverse transcription quantitative PCR (RT-qPCR), thereby indicating the potential application in clinical diagnosis and biomedical research.

Mutations in the miR-142 gene are not common in myeloproliferative neoplasms

Recent data indicate that MIR142 is the most frequently mutated miRNA gene and one of the most frequently mutated noncoding elements in all cancers, with mutations occurring predominantly in blood cancers, especially diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma. Functional analyses show that the MIR142 alterations have profound consequences for lympho- and myelopoiesis. Furthermore, one of the targets downregulated by miR-142-5p is CD274, which encodes PD-L1 that is elevated in many cancer types, including myeloproliferative neoplasms (MPNs). To extend knowledge about the occurrence of MIR142 mutations, we sequenced the gene in a large panel of MPNs [~ 700 samples, including polycythemia vera, essential thrombocythemia, primary myelofibrosis (PMF), and chronic myeloid leukemia], neoplasm types in which such mutations have never been tested, and in panels of acute myeloid leukemia (AML), and chronic lymphocytic leukemia (CLL). We identified 3 mutations (one in a PMF sample and two others in one CLL sample), indicating that MIR142 mutations are rare in MPNs. In summary, mutations in MIR142 are rare in MPNs; however, in specific subtypes, such as PMF, their frequency may be comparable to that observed in CLL or AML.

Abstract 1496: Circulating mir21 and mir125b in women living with human immunodeficiency virus: Utility of biomarkers for monitoring cervical carcinogenesis

Abstract Background: As of 2018, the prevalence of Human immunodeficiency virus (HIV), and cervical cancer (Ca) attributable to HIV was higher in Africa than in other continents. Identifying individuals at a high risk of developing Ca among immunocompromised persons, using less invasive techniques, remains a major challenge. Purpose: The study evaluated HIV infection-associated dysregulation of Ca-linked oncomirs (miR-21, miR-146a, miR-155, miR-182, and miR-200c) and tumor suppressors (miR-let-7b, miR-125b, miR-143, miR-145, and p53 gene), in a bid to identify early indicators of genetic instability, and biomarkers for monitoring of high-risk individuals. Methods: This case-control study included 173 women without abnormal Pap smear; confirmed HIV seropositive women (HIV+ = 103) and HIV seronegative women (HIV- = 70). Relative expressions of miRNAs and p53 gene in blood and cervical cells) were determined following RNA extraction, reverse transcriptase Polymerase Chain Reaction (PCR), and gel electrophoresis. T-test was used to compare the data from HIV+ and HIV- women. Significance was set at p≤ 0.05. Results: Similar pattern of miR-21, miR-146a, miR-182, miR-200c, miR-125b, and miR-145 expression was observed in both samples. Higher expressions of miR-155 and p53 gene were observed in cervical cells of HIV+ women compared with HIV- women (p= 0.046, and 0.033, respectively) whereas lower expressions of miR-155 and p53 gene were observed in the blood of HIV+ women compared with HIV- women (p= 0.539 and 0.049, respectively). In both blood and cervical cells, higher miR-21 expression (p= 0.032 and 0.198, respectively) and lower miR-125b expression (p= 0.050 and 0.004, respectively) were observed in HIV+ women compared with HIV-women. In blood, a lower expression of miR-146a was observed in HIV+ women compared with HIV- women (p= 0.036) whereas in cervical cells, lower expressions of miR-182 and miR-200c were observed in HIV+ women compared with HIV- women (p= 0.035 and 0.045, respectively). The low expression of miR-146a, miR-182, and miR-200c in HIV+ women could be due to immune exhaustion, viral immune evasive mechanism, or an indicator of viral latency while the higher expression of miR-21, and lower expression of miR-125b and p53 could be early indicators of genetic instability prior to epithelial transformation. Conclusion: This study suggests that circulating high expression of miR-21 and low expression of miR-125b and p53 gene could be used in identifying individuals at risk of developing Ca, especially among immunocompromised patients. Keywords: Human immunodeficiency virus, Cervical cancer, Detection, Biomarkers, MicroRNAs Citation Format: Jude Ogechukwu Okoye, Anthony Ajuluchukwu Ngokere, Charles Chinedum Onyenekwe, Samuel Ifedioranma Ogenyi, Olaposi Omotuyi. Circulating mir21 and mir125b in women living with human immunodeficiency virus: Utility of biomarkers for monitoring cervical carcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1496.

Abstract 1480: miR-21 as a post-transcriptional regulator of pancreatic ductal adenocarcinoma (PDAC) tumorigenesis

Abstract Introduction: MicroRNAs are short non-coding RNAs that are frequently dysregulated across cancers. Specifically, microRNA-21 (miR-21) is a known oncomir overexpressed in pancreatic adenocarcinoma (PDAC) that regulates multiple gene targets downstream of KRAS, the site of the primary driver mutation in PDAC. Past efforts to target mutant KRAS have been limited by compensatory activation of other growth pathways and treatment-related toxicity. Inhibiting miR-21 expression is a novel therapeutic strategy to target KRAS effector function through post-transcriptional regulation. We previously demonstrated that systemic inhibition of miRNA-21 (miR-21) intercepts tumorigenesis in the transgenic KrasG12D/+;Trp53R172H/+;Pdx-1-Cre (KPC) mice without causing overt toxicity. Our major goal was to verify the translation of the previous findings to human models and examine the mechanistic implications of miR-21 inhibition in PDAC. Experimental Procedures: Using publicly available data from a cohort of patients with PDAC in The Cancer Genome Atlas (TCGA), we performed differential expression analysis of miR-21 and KRAS-related gene targets as well as gene set enrichment analysis of oncogenic pathways identified by the Molecular Signatures Database (MSigDB). Concurrently, de-novo patient-derived organoid (PDO) models were generated from core biopsies and surgical resection specimens. To evaluate the effects of miR-21 inhibition on KRAS pathway activity in a human model system, we selected 6 PDO cell lines and determined miR-21 gene expression by quantitative PCR at baseline and after knockdown using a lentiviral construct. Results: Analysis of TCGA PDAC cohort identified heterogeneous endogenous expression of miR-21, which was validated ex vivo in our PDO model system. Gene set enrichment analysis revealed enrichment of gene sets associated with KRAS dependency, MEK, AKT, and MTOR signaling in patients with higher endogenous miR-21 expression. MiR-21 knockdown in PDO cell lines was stable at multiple intervals following lentiviral transduction. Further, expression of PDCD4, a tumor suppressor gene and target of miR-21 downstream of KRAS, was enhanced in PDO lines following miR-21 inhibition. Conclusions: We previously demonstrated that miR-21 appears to be an early and reliable molecular marker of pancreatic neoplasia and that systemic inhibition in a murine model intercepts PDAC tumorigenesis. We now demonstrate in human models that higher miR-21 expression is associated with enrichment of gene sets downstream of KRAS. Additionally, knocking down miR-21 expression enhances the expression of gene targets with tumor suppressor function, notably PDCD4. This suggests that modulating miR-21 expression subsequently modulates the expression of gene targets with critical cell regulatory functions and provides additional insight into novel therapeutic targets. Citation Format: Jacquelyn W. Zimmerman, Daniel H. Shu, Richard A. Burkhart, Joseph Tandurella, Elana J. Fertig, Elizabeth M. Jaffee. miR-21 as a post-transcriptional regulator of pancreatic ductal adenocarcinoma (PDAC) tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1480.

Abstract 5856: Differential expresion of miR-9 and their putative targets in prostate cancer

Abstract Background: Deregulation of microRNA (miRNA) plays an important role in the growth, invasion and migration of prostate cancer cells. miR-9 has been found overexpressed in prostate cancer (Pca) compared to benign prostate tissue (BPT) and proposed as an oncomiR with a potential as a therapeutic target. Little is known about the regulatory mechanisms of miR-9 in PCa and opposing roles in supporting or suppressing tumor development and metastasis has been reported in different tumor tissues. We aimed to explore the miR-9 expression and their putative targets in BPT and PCa tissue through in situ Hybridization (ISH) and bioinformatics analysis of miRNA and gene expression databases. Design: A prostate tissue microarray was constructed with representative areas of BPT and PCa. The expression of miR-9-5p was evaluated through a miRNAscope 2.5 LS Red ISH, it was scored using a semiquantitative analysis of the average number of dots per cell; mean score values were compared between BPT and PCa tissues using Mann-Whitney test, a p value less than 0.05 was considered statistically significant. We look for possible mir-9 targets in the database of experimentally validated microRNA-target (miRTarBase), and we use the AACR Project GENIE data base to analyze the behavior of the putative miR-9 targets in PCa vs BPT and explored their expression in the tumor tissues of the Cancer Genome Atlas (TCGA) through the bioinformatics tools of the GEPIA2 web server. Results: The analysis of miR-9 expression in 294 prostate tissue cores (145 BPT and 149 PCa) showed an overexpression of this miRNA in PCa (1.60, 95% CI:1.51-1.69) compared to BPT (0.86, 95% CI: 0.77-0.94), (p less than 0.0001). We identified 526 mir-9 target genes in the miRTarBase validated with at least one experimental assay, and selected the 24 genes with the strongest evidence of interaction with miR-9. The gene targets with higher expression level in PCa were CDH1, RAB34, AP3B1, CCNG1, SRF, TGFB1, ID2, FOXO3 y CCND1 (Log2 (TPM+1) &amp;gt; 4). Only 4 genes showed a statistically significant difference in their expression when BPT and PCa tissue data from the TCGA were compared. CDH1 was overexpressed in the PCa datasets and BCL6, RAB34 and NTRK3 were downregulated in cancer compared to normal tissues. Most of the miR-9 gene targets did not show alterations at the DNA sequence level according to the analysis of the AACR Project GENIE data using the cBioPortal, except for CDH1, BCL6, CCND1 and PRDM1, which showed truncating mutations, amplifications, deep deletion and splice mutations in some of the cancer datasets. These results suggest that mir-9 may be regulating tumor initiation, progression, and metastasis processes through the Neurotrophic Receptor Tyrosine Kinase 3 (NTRK3), which has been found altered in breast carcinomas and other cancers, or the downregulation of Cadherin 1 (CDH1), whose loss of function is thought to contribute to cancer progression by increasing proliferation, invasion, and metastasis. Citation Format: Ines Benedetti, Lia Barrios, Juan Rebollo. Differential expresion of miR-9 and their putative targets in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5856.

Novel targets in rectal cancer by considering lncRNA–miRNA–mRNA network in response to Lactobacillus acidophilus consumption: a randomized clinical trial

We aimed to explore the lncRNA–miR–mRNA network in response to Lactobacillusacidophilus (L. acidophilus) consumption in rectal cancer patients. The candidate miRs were first taken from the GEO and TCGA databases. We constructed the lncRNA–miR–mRNA network using the high-throughput sequencing data. At last, we created a heatmap based on the experimental data to show the possible correlation of the selected targets. The expression levels of selected targets were measured in the samples of 107 rectal cancer patients undergoing placebo and probiotic consumption and 10 noncancerous subjects using Real-Time PCR. Our analysis revealed a group of differentially expressed 12 miRs and 11 lncRNAs, and 12 genes in rectal cancer patients. A significant expression increase of the selected tumor suppressor miRs, lncRNAs, and genes and a substantial expression decrease of the selected oncomiRs, onco-lncRNAs, and oncogenes were obtained after the probiotic consumption compared to the placebo group. There is a strong correlation between some network components, including miR-133b and IGF1 gene, miR-548ac and MSH2 gene, and miR-21 and SMAD4 gene. In rectal cancer patients, L.acidophilus consumption was associated with improved expression of the lncRNA–miR–mRNA network, which may provide novel monitoring and therapeutic approaches.

Identification of Different miRNAs and Their Relevant miRNA Targeted Genes Involved in Sister Chromatid Cohesion and Segregation (SCCS)/chromatin Remodeling Pathway on T1G3 Urothelial Carcinoma (UC) Response to BCG Immunotherapy.

Till now, no definite clinical or laboratory marker can predict the recurrence or progression of T1 G3 urothelial carcinoma (UC). Genetic aberrations of the chromatin remodeling genes and sister chromatid cohesion and segregation (SCCS) were identified in UC. Here we investigated the impact of novel miRNAs and their targeted expressed SCCS and chromatin remodeling genes on T1G3 UC response to Bacillus Calmette-Guérin (BCG) therapy. One hundred tissue samples were obtained from NMIBC patients. Gene expression and immunohistochemical assay of STAG2, ARID1A, NCOR1and UTX were assessed. MiRNA analysis for their targeting miRNAs (miR-21, miR-31, Let7a and miR-199a) was carried out. Assessed genes were compared between responders and no responders to BCG. Univariate and multivariate analysis of predictors of disease recurrence and progression were performed using cox regression analysis. Thirty-two and 22 patients developed recurrence and progression to MIBC (BCG non-responders). BCG non-responders showed statistically significant higher expression of miR-21 and their targeted STAG2, miR-199a and NCOR1 gene (P < .001), and lower expression of miR-31, Let7a, ARID1A and UTX genes (P < .001). Higher miR-199a (P=.006) and lower miR-31 (P=.01), ARID1A (P=.008) and UTX (P=.03) were independent predictor of higher tumor recurrence. Recurrent disease (P=.003), higher expression of STAG2 (P=.01), NCOR1 (P=.01) and miR-21 (P=.03) genes and lower expression of miR-31 (P=.02), Let7a (P=.04) and ARID1A (P=.04) genes were the independent predictor of disease progression. Upregulation of STAG2 and NCOR1 and down regulation of ARID1A and UTX genes and their targeting miRNAs were associated with UC non-response to BCG.

Psoriatic Serum Induce an Abnormal Inflammatory Phenotype and a Decreased Immunosuppressive Function of Mesenchymal Stem Cells.

Background and ObjectivesMesenchymal stem cells (MSCs) have immunomodulatory function and participate in the pathogenesis of many immunoregulation-related diseases, including psoriasis. Previously, we found that MSCs from psoriatic lesions overexpress the proinflammatory microRNA, miR-155 and exhibit a decreased immunosuppressive capacity. But the origin of these aberrant characteristics is still not clear. To investigate whether inflammatory cytokines in serum and peripheral blood mononuclear cells (PBMCs) from psoriatic patients can regulate the expression patterns of immunoregulation-related cytokines and the immunoregulation function of MSCs.Methods and ResultsNormal dermal mesenchymal stem cells (nDMSCs) were treated with serum or PBMCs derived from patients with psoriasis or healthy donors. Expression of miR-155 and immunoregulation-related genes in each MSCs were measured using real-time PCR or western-blot. Meanwhile, the immunosuppressive capacity of DMSCs was evaluated by its inhibitory ability on proliferation of activated PBMCs. Compared to control serum, psoriatic serum significantly increased the expression levels of miR-155 (27.19±2.40 vs. 3.51±1.19, p<0.001), while decreased TAB2 expression (0.28±0.04 vs. 0.72±0.20, p<0.01) in DMSCs. Expression levels of immunoregulation-related genes such as PGE2, IL-10, and TLR4 were also markedly down-regulated following the psoriatic serum treatment. Those DMSCs treated with healthy serum could inhibit PBMC proliferation, while those psoriatic serum-treated DMSCs could not inhibit PBMC proliferation effectively.ConclusionsPsoriatic serum up-regulate the expression of miR-155, down-regulate the expression of immunoregulation-related genes (PGE2, IL-10, and TLR4) in DMSCs, and along with the inhibition of the immunosuppressive function of MSCs.

Exosomal PD-L1 confers chemoresistance and promotes tumorigenic properties in esophageal cancer cells via upregulating STAT3/miR-21.

Chemotherapy resistance remains a major obstacle in the treatment of esophageal cancer. Previous researches have shown that an increase in exosomal PD-L1 expression was positively associated with a more advanced clinical stage, a poorer prognosis as well as drug resistance in patients with esophageal squamous cell carcinoma (ESCC). To explore the role of exosomal PD-L1 in ESCC, we performed bioinformatics analysis as well as several in vitro/in vivo functional experiments in a parental sensitive cell line EC-9706 and its derivative, a paclitaxel-resistant subline EC-9706R, and found that the exosomal PD-L1 from EC-9706R was higher than that from EC-9706. Moreover, exosomes from EC-9706R significantly increased invasion, migration and chemoresistance of EC-9706. Anti-PD-L1 treatment in combination with chemotherapy also led to reduced tumor burden in vivo. Inhibition of the release of exosomes by GW4869 or inhibition of STAT3 phosphorylation by stattic could effectively reverse the resistance to paclitaxel mediated by exosomal PD-L1. Furthermore, we found that PD-L1, miR-21, and multidrug resistance (MDR1) gene are involved in the process of exosomal transfer. Moreover, PD-L1 could enhance miR-21 expression by increasing the enrichment of STAT3 on miR-21 promoter. Our results suggested that exosomal PD-L1 may contribute to drug resistance to paclitaxel by regulating the STAT3/miR-21/PTEN/Akt axis and promote tumorigenic phenotype. This study provides a novel potential therapeutic approach to reverse chemoresistance and tumor progression through exosomal PD-L1 in ESCC patients.

Effect of MiR-155 Knockout Mediated by Dual sgRNAs on Drug Sensitivity of FLT3-ITD+AML

Two sgRNAs transfected FLT3-ITD+AML cell line MV411 with different binding sites were introduced into CRISPR/cas9 to obtain MV411 cells with miR-155 gene knockout. To compare the efficiency of miR-155 gene knockout by single and double sgRNA transfection and their effects on cell phenotypes. The lentiviral vectors were generated containing either single sgRNA or dual sgRNAs and packaged into lentivirus particles. PCR was conducted to measure gene editing efficiency, and miR-155 expression was evaluated by qPCR. CCK-8 assay was used to evaluate the cell proliferation, and calculate drug sensitivity of cells to adriamycin and quizartinib. Annexin V-APC/7-AAD staining was used to label cell apoptosis induced by adriamycin and quizartinib. In the dual sgRNAs transfected cells, a cleavage band could be observed, meaning the success of gene editing. Compared with the single sgRNA transfected MV411 cells, the expression level of mature miR-155-5p was lower in the dual sgRNA transfected cells. And, dual sgRNA transfected MV411 were more sensitive to adriamycin and quizartinib with lower IC50 and higher apoptosis rate. The inhibition rate of miR-155 gene expression transfected by dual sgRNA is higher than that by single sgRNA. Dual sgRNA transfection can inhibit cell proliferation, reverse drug resistance, and induce apoptosis more significantly. Compared with single sgRNA transfection, dual sgRNA transfection is a highly efficient gene editing scheme.

LncRNA SND1-IT1 facilitates TGF-\u03b21-induced epithelial-to-mesenchymal transition via miR-124/COL4A1 axis in gastric cancer

The transformation of tumor cells from an epithelial to a mesenchymal-like phenotype, designated as epithelial-to-mesenchymal transition (EMT), represents a key hallmark of human cancer metastasis, including gastric cancer (GC). However, a large set of non-coding RNAs have been studied for their functions that initiate or inhibit this phenotypic switch in GC cells by regulating oncogenes or tumor suppressors. In this paper, we aimed to identify lncRNA SND1-IT1, miR-124, and COL4A1 gene in the context of GC with a specific focus on their effects on transforming growth factor β1 (TGF-β1)-induced EMT. The study included 52 paired samples of lesion tissues and adjacent lesion-free tissues surgically resected from patients diagnosed with GC. HGC-27 cells were stimulated with exogenous TGF-β1 (2 ng/mL). Expression of lncRNA SND1-IT1, miR-124, and COL4A1 was determined by RT-qPCR. CCK-8 assays, Transwell assays, immunoblotting analysis of EMT-specific markers, and tumor invasion markers were performed to evaluate cell viability, migration, and invasion of cultured HGC-27 cells. Luciferase activity assay was employed to examine miR-124 binding with lncRNA SND1-IT1 and COL4A1, respectively. LncRNA SND1-IT1 was upregulated in GC tissues and cells. TGF-β1-stimulated EMT and regulated lncRNA SND1-IT1, miR-124, and COL4A1 expressions in HGC-27 cells. LncRNA SND1-IT1 knockdown tempered HGC-27 cell viability, migration and invasion. LncRNA SND1-IT1 participated in TGF-β1-stimulated EMT in GC by sponging miR-124. MiR-124 attenuated TGF-β1-stimulated EMT in GC by targeting COL4A1. These results primarily demonstrated TGF-β1 can regulate cancer cell migration, invasion and stimulate EMT through the SND1-IT1/miR-124/COL4A1 axis in GC.

Significant Association of Variable Number Tandem Repeat Polymorphism rs58335419 in the MIR137 Gene With the Risk of Gastric and Colon Cancers.

The purpose of the article: The MIR137 gene acts as a tumor-suppressor gene in colon and gastric cancers. The aim of this study was to investigate the association of functional variable number tandem repeat (VNTR) polymorphism rs58335419 locating in the upstream of the MIR137 gene with the risk of colon and gastric cancers. Materials and methods: Totally, 429 individuals were contributed in the study, including 154 colon and 120 gastric cancer patients and 155 healthy controls. The target VNTR was genotyped using PCR and electrophoresis for all samples. Statistical analysis was performed using SPSS 21.0 software and by T, χ2 and logistic regression tests. Results: Excluding the rare genotypes, our results showed that genotype 3/5 (95% CI = 1.08–3.73, OR = 2.01, p = 0.026) significantly increased the risk of colon cancer but not gastric cancer (95% CI = 0.88–3.30, OR = 1.70, p = 0.114). Also, in the stratification analysis for VNTRs and sex, genotypes 3/4 (95% CI = 1.00–6.07, OR = 2.46, p = 0.049) and 3/5 (95% CI = 1.25–7.18, OR = 2.99, p = 0.014) significantly increased the risk of colon cancer in men but not in women. In addition, all genotypes including the rare genotypes as a group, significantly increase the risk of gastric (95% CI = 1.14–3.00, OR = 1.85, p = 0.012) and colon (95% CI = 1.38–3.43, OR = 2.17, p = 0.001) cancers compared to the genotype 3/3 as a reference. Conclusion: The results show that increasing the copy of VNTR in the MIR137 gene, increases the risk of colon and gastric cancers and can serve as a marker for susceptibility to colon and gastric cancers.

Onco-miR-21 Promotes Stat3-Dependent Gastric Cancer Progression.

Simple SummaryMicroRNAs (miRNAs) are a class of highly conserved small, non-protein coding RNAs with often-deregulated expression in cancer. miR-21 is a well-studied cancer-associated microRNA which is able to regulate proliferation, apoptosis, and invasion. The aim of this study was to investigate the molecular pathways which govern miR-21 expression in gastric cancer (GC), and to assess the therapeutic benefit of targeting miR-21 function with a small, synthetic miR-21 antagomir. We confirmed that miR-21 expression in a preclinical model of early gastric cancer is dependent on Stat3 downstream of the IL-6 family cytokine-mediated activation of gp130 receptor signaling. Antagomir therapy curbed gastric tumor growth, and restricted epithelial-to-mesenchymal transition and matrix remodeling. Our study established miR-21 as a promising anti-cancer target in GC.MicroRNA-21 (miR-21) is a small, non-coding RNA overexpressed in gastric cancer and many other solid malignancies, where it exhibits both pro-and anti-tumourigenic properties. However, the pathways regulating miR-21 and the consequences of its inhibition in gastric cancer remain incompletely understood. By exploiting the spontaneous Stat3-dependent formation of inflammation-associated gastric tumors in Gp130F/F mice, we functionally established miR-21 as a Stat3-controlled driver of tumor growth and progression. We reconciled our discoveries by identifying several conserved Stat3 binding motifs upstream of the miR-21 gene promoter, and showed that the systemic administration of a miR-21-specific antisense oligonucleotide antagomir reduced the established gastric tumor burden in Gp130F/F mice. We molecularly delineated the therapeutic benefits of miR-21 inhibition with the functional restoration of PTEN in vitro and in vivo, alongside an attenuated epithelial-to-mesenchymal transition and the extracellular matrix remodeling phenotype of tumors. We corroborated our preclinical findings by correlating high STAT3 and miR-21 expression with the reduced survival probability of gastric cancer patients. Collectively, our results provide a molecular framework by which miR-21 mediates inflammation-associated gastric cancer progression, and establish miR-21 as a robust therapeutic target for solid malignancies characterized by excessive Stat3 activity.

Age-related Loss of miR-124 Causes Cognitive Deficits via Derepressing RyR3 Expression.

Epigenetic alterations of brain contribute to age-related cognitive decline. The challenge now is to identify these tractable epigenetic molecules working as the downstream cell-signaling nodes mediating age-related cognitive decline. Here we reported age-related loss of miR-124 in human and rat brains. To further validate these findings, knockout mice in which one of the three miR-124 genes (miR-124-3) was deleted using CRISPR/Cas9-mediated gene engineering were generated. MiR-124-3 knockout mice developed cognitive deficit phenotype. MiR-124 deficiency in the mouse brain resulted in upregulation of the Ryanodine receptor 3 (RyR3) gene, and the cognitive deficits in miR-124-3 knockout mice were ameliorated by knocking down RyR3 expression using RNAi. In addition, miR-124 deficiency facilitated Aβ42-induced neuron apoptosis. Our work suggested that age-related cognitive decline, at least in part, was associated with miR-124 deficiency and subsequently upregulated RyR3 expression in inducing neuronal death.

Comparative evaluation of microRNA-155 expression level and its correlation with tumor necrotizing factor α and interleukin 6 in patients with chronic periodontitis

MicroRNAs are a class of small noncoding ribonucleic acids that perform a critical role in adjustment of gene expression. miRNAs-155 (miR-155) participates in controlling inflammation. Periodontitis is defined as inflammatory disorder of tissues surrounding the teeth. In this study, the expression levels of miR-155 and its target genes, tumor necrotizing factor alpha (TNF-α), and interleukin-6 (IL-6) were evaluated in a group of Iranian patients. This sectional study was performed on 10 healthy controls and 10 individuals with chronic periodontitis by means of polymerase chain reaction (PCR) test. For each individual, clinical parameters including probing depth and clinical attachment loss and blood samples were measured. Levels of miR-155, TNF-α, and IL-6 were quantified using real-time PCR (α=0/05) and the results were analyzed by Mann-Whitney U test. The level of miR-155 was significantly higher in patients with chronic periodontitis (P < 0.001). A positive correlation was observed between the level of miR-155 and clinical parameters (P < 0.05). Level of miR-155 in tissue samples was correlated with blood samples although the expression level was higher in blood samples. As the expression level of miR-155, TNF-α, and IL-6 genes was higher in subjects with chronic periodontitis than healthy individuals, it might suggest a role for miR-155 in patients with chronic periodontitis.

Promoter Hypomethylation of miR-124 Gene Is Associated With Major Depressive Disorder

Based on our previous studies and other evidence, miR-124 is an important biomarker and therapeutic target for major depressive disorder (MDD). The aim of this study was to clarify the role of miR-124 methylation in MDD and antidepressant effects from the perspective of epigenetics. MethylTarget™ was used to detect methylation levels of the three miR-124 precursor genes (MIR124-1, MIR124-2, and MIR124-3) in 33 pre- and post-treatment MDD patients and 33 healthy controls. A total of 11 cytosine-phosphate-guanine (CpG) islands in the three miR-124 precursor genes, including 222 CpG sites, were detected. All CpG islands were hypomethylated in MDD patients when compared to healthy controls and seven CpG regions were still identified with a statistically significant difference after Bonferroni correction. In addition, 137 of 222 CpG sites were found a statistical difference between MDD patients and controls, and 40 CpG sites were still statistically significant after Bonferroni correction. After performing the LASSO regression model, seven biomarkers with differential methylation among 40 CpG sites were identified. Mean methylation score was lower in MDD patients (z = −5.84, p = 5.16E-9). The AUC value reached 0.917 (95% CI: 0.854–0.981) to discriminate MDD and controls. No changes in methylation of the three miR-124 precursor genes were found in MDD patients following antidepressant treatment. The methylation of miR-124 could be a promising diagnostic biomarker for MDD.