miR-129 regulates cell proliferation by downregulating Cdk6 expression

Development of a 5-FU modified miR-129 mimic as a therapeutic for non-small cell lung cancer

Lung cancer is the leading cause of cancer-related deaths in the United States with non-small cell lung cancer (NSCLC) accounting for most cases. Despite advances in cancer therapeutics, the 5-year survival rate has remained poor due to several contributing factors, including its resistance to therapeutics. Therefore, there is a pressing need to develop therapeutics that can overcome resistance. Non-coding RNAs, including microRNAs (miRNAs), have been found to contribute to cancer resistance and therapeutics by modulating the expression of several targets involving multiple key mechanisms. In this study, we investigated the therapeutic potential of miR-129 modified with 5-fluorouracil (5-FU) in NSCLC. Our results show that 5-FU modified miR-129 (5-FU-miR-129) inhibits proliferation, induces apoptosis, and retains function as an miRNA in NSCLC cell lines A549 and Calu-1. Notably, we observed that 5-FU-miR-129 was able to overcome resistance to tyrosine kinase inhibitors and chemotherapy in cell lines resistant to erlotinib or 5-FU. Furthermore, we observed that the inhibitory effect of 5-FU-miR-129 can also be achieved in NSCLC cells under vehicle-free conditions. Finally, 5-FU-miR-129 inhibited NSCLC tumor growth and extended survival in vivo without toxic side effects. Altogether, our results demonstrate the potential of 5-FU-miR-129 as a highly potent cancer therapeutic in NSCLC.

Suberoylanilide hydroxamic acid (SAHA) attenuates memory impairment in the offspring of rats exposed to sevoflurane anesthesia

BACKGROUND

SAHA was reported to enhance the expression of miR-129-5p, which was predicted to bind to 3' UTR of CASP-6, a gene playing crucial roles in the pathogenesis of memory impairment. Whether SAHA/miR-129-5p/CASP-6 is involved in the pathogenesis of prenatal exposure to sevoflurane remains to be explored.

METHODS

Morris water maze test was performed to evaluate the functional parameters of learning and memory. Quantitative real-time qPCR was carried out to analyze the expression of miRNAs and CASP-6 mRNA under different conditions.

RESULTS

Sevoflurane exposure of pregnant rats and SAHA treatment of the offspring had no effect on the blood gases, litter size, survival rate and weight. SAHA administration remarkably reversed the learning and memory impairment in prenatal rats caused by sevoflurane exposure. Mechanistically, the abnormal expression of miR-129-5p and CASP-6 in the offspring of pregnant rats exposed to sevoflurane was effectively restored by SAHA treatment. The luciferase activity of CASP-6 vector was effectively inhibited by miR-129-5p in primary neuron cells of rats. Moreover, the expression of CASP-6 mRNA and protein was significantly suppressed by miR-129-5p and SAHA treatment in a dose-dependent manner.

CONCLUSION

Our work demonstrated that the administration of SAHA suppressed the expression of CASP-6 via modulating the expression of miR-129-5p, and SAHA may rescue the apoptosis of neurons caused by exposure to sevoflurane. The underlying mechanism might be the ability of SAHA to relieve learning and memory impairment in the offspring of the pregnant rats exposed to sevoflurane.

Development of 5-FU-modified tumor suppressor microRNAs as a platform for novel microRNA-based cancer therapeutics

MicroRNA (miRNAs) are pleiotropic post-transcriptional modulators of gene expression. Their inherently pleiotropic nature makes miRNAs strong candidates for the development of cancer therapeutics, yet despite their potential, there remains a challenge to deliver nucleic acid-based therapies into cancer cells. We developed a novel approach to modify miRNAs by replacing the uracil bases with 5-fluorouracil (5-FU) in the guide strand of tumor suppressor miRNAs, thereby combining the therapeutic effect of 5-FU with tumor-suppressive effect of miRNAs to create a potent, multi-targeted therapeutic molecule without altering its native RNAi function. To demonstrate the general applicability of this approach to other tumor-suppressive miRNAs, we screened a panel of 12 novel miRNA mimetics in several cancer types, including leukemia, breast, gastric, lung, and pancreatic cancer. Our results show that 5-FU-modified miRNA mimetics have increased potency (low nanomolar range) in inhibiting cancer cell proliferation and that these mimetics can be delivered into cancer cells without delivery vehicle both in vitro and in vivo, thus representing significant advancements in the development of therapeutic miRNAs for cancer. This work demonstrates the potential of fluoropyrimidine modifications that can be broadly applicable and may serve as a platform technology for future miRNA and nucleic acid-based therapeutics.

Screening and identification of miRNAs regulating Tbx4/5 genes of Pampus argenteus

Background

Silver pomfret (Pampus argenteus) is one of the most widely distributed and economically important pelagic fish species. However, an unique morphological feature of P. argenteus is the loss of pelvic fins, which can increase the energy requirement during food capture to some extent and is therefore not conducive to artificial culture. Tbx4/5 genes are highly conserved regulatory factors that regulate limb development in vertebrates and are in turn regulated by microRNAs (miRNAs). However, the miRNAs that directly regulate the Tbx4/5 genes in P. argenteus remain to be elucidated.

Methods

The Tbx4/5 genes of P. argenteus were first cloned, and the small RNA transcriptomes were sequenced by high-throughput sequencing during the critical period of the fin development at days 1, 7, and 13 of hatching. The miRNAs regulating the Tbx4/5 genes of P. argenteus were subsequently predicted by bioinformatics analysis, and the related miRNAs were verified in vitro using a dual fluorescence reporter system.

Results

A total of 662 miRNAs were identified, of which 257 were known miRNAs and 405 were novel miRNAs were identified. Compared to day 1, 182 miRNAs were differentially expressed (DE) on day 7, of which 77 and 105 miRNAs were downregulated and upregulated, respectively, while 278 miRNAs were DE on day 13, of which 136 and 142 miRNAs were downregulated and upregulated, respectively. Compared to day 13, four miRNAs were DE on day 7, of which three miRNAs were downregulated and one miRNA was upregulated. The results of hierarchical clustering of the miRNAs revealed that the DE genes were inversely expressed between days 1 and 7, and between days 1 and 13 of larval development, indicating that the larvae were in the peak stage of differentiation. However, the number of DE genes between days 7 and 13 of larval development was relatively small, suggesting the initiation of development. The potential target genes of the DE miRNAs were subsequently predicted, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of target genes were performed. The results suggested that the DE miRNAs were involved in growth, development, and signal transduction pathways, of which the Wnt and Fgfs signaling pathways are known to play important roles in the growth and development of fins. The results of dual fluorescence reporter assays demonstrated that miR-102, miR-301c, and miR-589 had a significant negative regulatory effect on the 3'-UTR of the Tbx4 gene, while miR-187, miR-201, miR-219, and miR-460 had a significant negative regulatory effect on the 3'-UTR of the Tbx5 gene. Altogether, the findings indicated that miRNAs play an important role in regulating the growth and development of pelvic fins in P. argenteus. This study provides a reference for elucidating the interactions between the miRNAs and target genes of P. argenteus in future studies.

Cell cycle associated miRNAs as target and therapeutics in lung cancer treatment

Lung cancer is the primary cause of cancer related deaths worldwide. Limited therapeutic options and resistance to existing drugs are the major hindrances to the clinical success of this cancer. In the past decade, several studies showed the role of microRNA (miRNA) driven cell cycle regulation in lung cancer progression. Therefore, these small nucleotide molecules could be utilized as promising tools in lung cancer therapy. In this review, we highlighted the recent advancements in lung cancer therapy using cell cycle linked miRNAs. By highlighting the roles of the specific cell cycle core regulators affiliated miRNAs in lung cancer, we further outlined how these miRNAs can be explored in early diagnosis and treatment strategies to prevent lung cancer. With the provided information from our review, more medical efforts can ensure a potential breakthrough in miRNA-based lung cancer therapy.

Structure-guided design and development of cyclin-dependent kinase 4/6 inhibitors: A review on therapeutic implications

Cyclin-dependent kinase 6 (EC 2.7.11.22) play significant roles in numerous biological processes and triggers cell cycle events. CDK6 controlled the transcriptional regulation. A dysregulated function of CDK6 is linked with the development of progression of multiple tumor types. Thus, it is considered as an effective drug target for cancer therapy. Based on the direct roles of CDK4/6 in tumor development, numerous inhibitors developed as promising anti-cancer agents. CDK4/6 inhibitors regulate the G1 to S transition by preventing Rb phosphorylation and E2F liberation, showing potent anti-cancer activity in several tumors, including HR+/HER2- breast cancer. CDK4/6 inhibitors such as abemaciclib, palbociclib, and ribociclib, control cell cycle, provoke cell senescence, and induces tumor cell disturbance in pre-clinical studies. Here, we discuss the roles of CDK6 in cancer along with the present status of CDK4/6 inhibitors in cancer therapy. We further discussed, how structural features of CDK4/6 could be implicated in the design and development of potential anti-cancer agents. In addition, the therapeutic potential and limitations of available CDK4/6 inhibitors are described in detail. Recent pre-clinical and clinical information for CDK4/6 inhibitors are highlighted. In addition, combination of CDK4/6 inhibitors with other drugs for the therapeutic management of cancer are discussed.

Phenotype Identification of HeLa Cells Knockout CDK6 Gene Based on Label-Free Raman Imaging

Identifying cell phenotypes is essential for understanding the function of biological macromolecules and molecular biology. We developed a noninvasive, label-free, single-cell Raman imaging analysis platform to distinguish between the cell phenotypes of the HeLa cell wild type (WT) and cyclin-dependent kinase 6 (CDK6) gene knockout (KO) type. Via large-scale Raman spectral and imaging analysis, two phenotypes of the HeLa cells were distinguished by their intrinsic biochemical profiles. A significant difference was found between the two cell lines: large lipid droplets formed in the knockout HeLa cells but were not observed in the WT cells, which was confirmed by Oil Red O staining. The band ratio of the Raman spectrum of saturated/unsaturated fatty acids was identified as the Raman spectral marker for HeLa cell WT or gene knockout type differentiation. The interaction between organelles involved in lipid metabolism was revealed by Raman imaging and Lorentz fitting, where the distribution intensity of the mitochondria and the endoplasmic reticulum membrane decreased. At the same time, lysosomes increased after the CDK6 gene knockout. The parameters obtained from Raman spectroscopy are based on hierarchical cluster analysis and one-way ANOVA, enabling highly accurate cell classification.

Effect of Helicobacter pylori Eradication on Epigenetic Changes in Gastric Cancer-related Genes

It is known that gastric carcinogenesis results from the progressive changes from chronic gastritis to gastric atrophy, intestinal metaplasia, dysplasia, and invasive carcinoma. Several genetic and epigenetic alterations are involved in this process, and Helicobacter pylori (H. pylori) infection is believed to induce the initiation and progression of these steps. From an epigenetic point of view, H. pylori induces hypermethylation of genes involved in the development of gastric cancer and regulates the expression of various microRNAs (miRNAs). These H. pylori-related epigenetic changes are accumulated not only at the site of neoplasm but also in the adjacent non-cancerous gastric mucosa. Thereby, a state vulnerable to gastric cancer known as an epigenetic field defect is formed. H. pylori eradication can have an effective chemopreventive effect in gastric carcinogenesis. However, the molecular biological changes that occur in the stomach environment during H. pylori eradication have not yet been established. Several studies have reported that H. pylori eradication can restore infection-related changes, especially epigenetic alterations in gastric cancer-related genes, but some studies have shown otherwise. Simply put, it appears that the recovery of methylated gastric cancer-related genes and miRNAs during H. pylori eradication may vary among genes and may also differ depending on the histological subtype of the gastric mucosa. In this review, we will discuss the potential mechanism of gastric cancer prevention by H. pylori eradication, mainly from an epigenetic perspective.

The role of miR-129-5p in cancer: a novel therapeutic target

MiRNA-129-5p belongs to the microRNA-129 (miRNA-129) family. MiRNA-129-5p is expressed in many tissues and organs of the human body, and it regulates a wide range of biological functions. The abnormal expression of miRNA-129-5p is related to the occurrence and development of a variety of malignant tumors. MiRNA-129-5p plays an important role in the tumorigenesis process and functions by promoting or inhibiting tumors. However, the role of miRNA-129-5p in cancer remains controversial. This article reviews the different biological functions of miRNA-129-5p in cancer and provides ideas for research in this field to guide the development of targeted therapies and drugs for malignant tumors.

Predictions of the dysregulated competing endogenous RNA signature involved in the progression of human lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) is the most common histological subtype of lung cancer worldwide. Until now, the molecular mechanisms underlying LUAD progression have not been fully explained. This study aimed to construct a competing endogenous RNA (ceRNA) network to predict the progression in LUAD.

METHODS

Differentially expressed lncRNAs (DELs), miRNAs (DEMs), and mRNAs (DEGs) were identified from The Cancer Genome Atlas (TCGA) database with a |log2FC|> 1.0 and a false discovery rate (FDR) < 0.05. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), protein-protein interaction (PPI) network, and survival analyses were performed to analyse these DEGs involved in the ceRNA network. Subsequently, the drug-gene interaction database (DGIdb) was utilized to select candidate LUAD drugs interacting with significant DEGs. Then, lasso-penalized Cox regression and multivariate Cox regression models were used to construct the risk score system. Finally, based on the correlations between DELs and DEGs involved in the risk score system, the final ceRNA network was identified. Meanwhile, the GEPIA2 database and immunohistochemical (IHC) results were utilized to validate the expression levels of selected DEGs.

RESULTS

A total of 340 DELs, 29 DEMs, and 218 DEGs were selected to construct the initial ceRNA network. Functional enrichment analyses indicated that 218 DEGs were associated with the KEGG pathway terms "microRNAs in cancer", "pathways in cancer", "cell cycle", "HTLV-1 infection", and the "PI3K-Akt signalling pathway". K-M survival analysis of all differentially expressed genes involved in the ceRNA network identified 24 DELs, 4 DEMs, and 29 DEGs, all of which were significantly correlated with LUAD progression (P< 0.05). Furthermore, 15 LUAD drugs interacting with 29 significant DEGs were selected. After lasso-penalized Cox regression and multivariate Cox regression modelling, PRKCE, DLC1, LATS2, and DPY19L1 were incorporated into the risk score system, and the results suggested that LUAD patients who had the high-risk score always suffered from a poorer overall survival. Additionally, the correlation coefficients between these 4 DEGs and their corresponding DELs involved in the ceRNA network suggested that there were 2 significant DEL-DEG pairs, NAV2-AS2 - PRKCE (r= 0.430, P< 0.001) and NAV2-AS2 - LATS2 (r= 0.338, P< 0.001). And NAV2-AS2 - mir-31 - PRKCE and NAV2-SA2 - mir-31 - LATS2 were finally identified as ceRNA network involved in the progression of LUAD.

CONCLUSIONS

The lncRNA-miRNA-mRNA ceRNA network plays an essential role in predicting the progression of LUAD. These results may improve our understanding and provide novel mechanistic insights to explore prognosis and therapeutic drugs for LUAD patients.

MicroRNAs Determining Carcinogenesis by Regulating Oncogenes and Tumor Suppressor Genes During Cell Cycle

AIM

To provide a review considering microRNAs regulating oncogenes and tumor suppressor genes during the different stages of cell cycle, controlling carcinogenesis.

METHODS

The role of microRNAs involved as oncogenes' and tumor suppressor genes' regulators in cancer was searched in the relevant available literature in MEDLINE, including terms such as "microRNA", "oncogenes", "tumor suppressor genes", "metastasis", "cancer" and others.

RESULTS

MicroRNAs determine the expression levels of multiple cell cycle regulators, such as cyclins, cyclin dependent kinases and other major cell cycle activators including retinoblastoma 1 (RB- 1) and p53, resulting in alteration and promotion/inhibition of the cell cycle.

CONCLUSION

MicroRNAs are proven to have a key role in cancer pathophysiology by altering the expression profile of different regulator proteins during cell division cycle and DNA replication. Thus, by acting as oncogenes and tumor suppressor genes, they can either promote or inhibit cancer development and formation, revealing their innovative role as biomarkers and therapeutic tools.

Small Non-Coding-RNA in Gynecological Malignancies

Gynecologic malignancies, which include cancers of the cervix, ovary, uterus, vulva, vagina, and fallopian tube, are among the leading causes of female mortality worldwide, with the most prevalent being endometrial, ovarian, and cervical cancer. Gynecologic malignancies are complex, heterogeneous diseases, and despite extensive research efforts, the molecular mechanisms underlying their development and pathology remain largely unclear. Currently, mechanistic and therapeutic research in cancer is largely focused on protein targets that are encoded by about 1% of the human genome. Our current understanding of 99% of the genome, which includes noncoding RNA, is limited. The discovery of tens of thousands of noncoding RNAs (ncRNAs), possessing either structural or regulatory functions, has fundamentally altered our understanding of genetics, physiology, pathophysiology, and disease treatment as they relate to gynecologic malignancies. In recent years, it has become clear that ncRNAs are relatively stable, and can serve as biomarkers for cancer diagnosis and prognosis, as well as guide therapy choices. Here we discuss the role of small non-coding RNAs, i.e., microRNAs (miRs), P-Element induced wimpy testis interacting (PIWI) RNAs (piRNAs), and tRNA-derived small RNAs in gynecological malignancies, specifically focusing on ovarian, endometrial, and cervical cancer.

The Role of miRNA-7 in the Biology of Cancer and Modulation of Drug Resistance

MicroRNAs (miRNAs, miRs) are small non-coding RNA (ncRNA) molecules capable of regulating post-transcriptional gene expression. Imbalances in the miRNA network have been associated with the development of many pathological conditions and diseases, including cancer. Recently, miRNAs have also been linked to the phenomenon of multidrug resistance (MDR). MiR-7 is one of the extensively studied miRNAs and its role in cancer progression and MDR modulation has been highlighted. MiR-7 is engaged in multiple cellular pathways and acts as a tumor suppressor in the majority of human neoplasia. Its depletion limits the effectiveness of anti-cancer therapies, while its restoration sensitizes cells to the administered drugs. Therefore, miR-7 might be considered as a potential adjuvant agent, which can increase the efficiency of standard chemotherapeutics.

Silencing long non-coding RNA NEAT1 attenuates rheumatoid arthritis via the MAPK/ERK signalling pathway by downregulating microRNA-129 and microRNA-204

The participation of long noncoding RNAs (lncRNAs) and microRNAs (miRs) in the progression of rheumatoid arthritis (RA) is a key area of investigation. The current study aimed to investigate the action of lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in fibroblast-like synoviocyte (FLS) proliferation and synovitis in RA. A rat model of RA was established. LncRNA NEAT1 expression in the synovial tissues of patients with RA and FLSs from the RA rat model was determined using RT-qPCR. Next, dual luciferase reporter gene assay was applied to investigate the relationship between miR-129/204 and mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinase (ERK). A putative binding relationship between miR-204 and lncRNA NEAT1 was evaluated by RIP assay, and miR-129 promoter methylation was determined using MSP. After the expression of lncRNA NEAT1, miR-129 or miR-204 was altered in FLSs, the extent of ERK1/2 phosphorylation was assessed. In addition, FLS synovitis and proliferation were determined by ELISA and EdU assay, respectively. In RA rats, lncRNA NEAT1 was silenced and miR-129/miR-204 was overexpressed to explore their roles in vivo. LncRNA NEAT1 was upregulated, while miR-129 and miR-204 were downregulated in RA synovial tissues and FLSs. MAPK1 was target gene of both miR-129 and miR-204. LncRNA NEAT1 bound to miR-204 and promoted miR-129 promoter methylation. Silencing lncRNA NEAT1 or overexpressing miR-129/miR-204 enhanced miR-129/miR-204 expression, but reduced the extent of ERK1/2 phosphorylation, proliferation of FLSs, and synovitis in RA. Collectively, silencing lncRNA NEAT1 promoted miR-129 and miR-204 to inhibit the MAPK/ERK signalling pathway, reducing FLS synovitis in RA.Abbreviations: ACR: American College of Rheumatology; ELISA: Enzyme-linked immunosorbent assay; ERK: extracellular signal-regulated kinase; FLS: fibroblast-like synoviocyte; GADPH: glyceraldehyde-3-phosphate dehydrogenase; HRP: horseradish peroxidase; IFA: Incomplete Freund's Adjuvant; lncRNAs: long noncoding RNAs; MSP: Methylation-specific PCR; NC: negative control; NEAT1: nuclear paraspeckle assembly transcript 1; OD: optical density; RA: rheumatoid arthritis; RIPA: Radio Immunoprecipitation Assay; RLU: relative light units; RT-qPCR: reverse transcription quantitative polymerase chain reaction; UTR: untranslated region.

Epigenetics and microRNAs in cardiovascular diseases

Cardiovascular diseases are among the leading causes of mortality worldwide. Besides environmental and genetic changes, these disorders can be influenced by processes which do not affect DNA sequence yet still play an important role in gene expression and which can be inherited. These so-called 'epigenetic' changes include DNA methylation, histone modifications, and ATP-dependent chromatin remodeling enzymes, which influence chromatin remodeling and gene expression. Next to these, microRNAs are non-coding RNA molecules that silence genes post-transcriptionally. Both epigenetic factors and microRNAs are known to influence cardiac development and homeostasis, in an individual fashion but also in a complex regulatory network. In this review, we will discuss how epigenetic factors and microRNAs interact with each other and how together they can influence cardiovascular diseases.

Knockdown of KCNQ1OT1 Inhibits Proliferation, Invasion, and Drug Resistance by Regulating miR-129-5p-Mediated LARP1 in Osteosarcoma

KCNQ1OT1 exerts an important role in various cancers, but its role in osteosarcoma (OS) and the potential mechanism remain to be clarified. In the present research, we aimed to explore the effect of KCNQ1OT1 on osteosarcoma and further explore the special molecular mechanism. The expression of KCNQ1OT1 was analyzed in tumor and adjacent tissues of 30 patients with osteosarcoma by RT-PCR. Cell proliferation and invasion were explored using MTT and transwell assay, respectively. Luciferase reporter analysis and pull-down assay were performed to determine the binding activity of KCNQ1OT1 and miR-129-5p. The result revealed that KCNQ1OT1 was highly expressed in osteosarcoma tissues and cells. KCNQ1OT1-siRNA inhibited the proliferation, invasion, and drug resistance of osteosarcoma cells. The luciferase reporter assay and pull-down assay demonstrated that KCNQ1OT1 directly interact with miR-129-5p. In addition, miR-129-5p binds to LARP1 directly, and LARP1 promoted the proliferation, invasion, and drug resistance of osteosarcoma cells. What is more, KCNQ1OT1 promoted proliferation, invasion, and drug resistance via inhibiting the expression of miR-129-5p and further promoting the expression of miR-129-5p-mediated LARP1. Collectively, it suggests that downregulation of KCNQ1OT1 inhibits proliferation, invasion, and drug resistance by regulating miR-129-5p-mediated LARP1 in osteosarcoma cells.

miR129-1 regulates protein phosphatase 1D protein expression under hypoxic conditions in non-small cell lung cancer cells harboring a TP53 mutation

Protein phosphatase 1D (PPM1D), which functions as an oncogene, is a known target of the tumor suppressor p53 and is involved in p53-regulated genomic surveillance mechanisms. PPM1D dephosphorylates both p53 and its ubiquitin ligase mouse double minute 2 homolog, as well as the RNA-binding protein (RBM)38, which turns RBM38 from an inducer to inhibitor of TP53 translation. In addition, RBM38 induces PPM1D translation. Hence, the PPM1D-RBM38-p53 axis is important in maintaining genomic integrity and is often altered during tumorigenesis. TP53, which encodes p53, is deleted or mutated in >50% of cancer types, including lung cancer. Mutant p53 has been revealed to complex with hypoxia-inducible factor 1α (HIF1α) and upregulate transcription of pro-metastatic genes. However, the mechanism underlying the action of the PPM1D-RBM38-p53 axis in the context of mutant p53 under normoxic and hypoxic conditions is yet to be elucidated. In the present study, using non-small cell lung cancer (NSCLC) cell lines harboring wild-type (A549 cells) or hot-spot mutant (NCI-H1770 and R249WΔ-TP53-A549 cells) TP53, it was demonstrated that in cells harboring mutant p53, RBM38 was not the primary regulator of PPM1D translation under hypoxic conditions. Knockdown of RBM38 in TP53 mutant cells did not affect the PPM1D protein expression under hypoxic conditions. Instead, in NCI-H1770 cells maintained under normoxic conditions, PPM1D was revealed as a target of micro RNA (miR)-129-1-3p, a known tumor suppressor in lung cancer. Hypoxia resulted in the downregulation of miR-129-1-3p expression, and thus, in the downregulation of PPM1D messenger RNA (mRNA) translation. In NCI-H1770 cells grown under hypoxic conditions, the transient transfection of miR-129-1-3p mimic, and not control mimic, repressed the expression of a reporter containing wild-type, but not miR-129-1-3p binding mutant, of the PPM1D 3'-untranslated region (UTR). Analysis of NSCLC cell lines from the Broad Institute Cancer Cell Encyclopedia and patients with NSCLC from The Cancer Genome Atlas dataset revealed significant co-occurrence of PPM1D/RBM38 and PPM1D/HIF1A mutations. However, there was no significant difference in the overall survival of patients with NSCLC with or without genomic alterations in TP53, RBM38, PPM1D and HIF1A. In summary, the current study demonstrated hypoxia-dependent miR-129-1-3p-mediated regulation of PPM1D protein expression in NSCLC cell line harboring mutant TP53.

The Prediction of miRNAs in SARS-CoV-2 Genomes: hsa-miR Databases Identify 7 Key miRs Linked to Host Responses and Virus Pathogenicity-Related KEGG Pathways Significant for Comorbidities

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a member of the betacoronavirus family, which causes COVID-19 disease. SARS-CoV-2 pathogenicity in humans leads to increased mortality rates due to alterations of significant pathways, including some resulting in exacerbated inflammatory responses linked to the “cytokine storm” and extensive lung pathology, as well as being linked to a number of comorbidities. Our current study compared five SARS-CoV-2 sequences from different geographical regions to those from SARS, MERS and two cold viruses, OC43 and 229E, to identify the presence of miR-like sequences. We identified seven key miRs, which highlight considerable differences between the SARS-CoV-2 sequences, compared with the other viruses. The level of conservation between the five SARS-CoV-2 sequences was identical but poor compared with the other sequences, with SARS showing the highest degree of conservation. This decrease in similarity could result in reduced levels of transcriptional control, as well as a change in the physiological effect of the virus and associated host-pathogen responses. MERS and the milder symptom viruses showed greater differences and even significant sequence gaps. This divergence away from the SARS-CoV-2 sequences broadly mirrors the phylogenetic relationships obtained from the whole-genome alignments. Therefore, patterns of mutation, occurring during sequence divergence from the longer established human viruses to the more recent ones, may have led to the emergence of sequence motifs that can be related directly to the pathogenicity of SARS-CoV-2. Importantly, we identified 7 key-microRNAs (miRs 8066, 5197, 3611, 3934-3p, 1307-3p, 3691-3p, 1468-5p) with significant links to KEGG pathways linked to viral pathogenicity and host responses. According to Bioproject data (PRJNA615032), SARS-CoV-2 mediated transcriptomic alterations were similar to the target pathways of the selected 7 miRs identified in our study. This mechanism could have considerable significance in determining the symptom spectrum of future potential pandemics. KEGG pathway analysis revealed a number of critical pathways linked to the seven identified miRs that may provide insight into the interplay between the virus and comorbidities. Based on our reported findings, miRNAs may constitute potential and effective therapeutic approaches in COVID-19 and its pathological consequences.

MiR-129-5p induces cell cycle arrest through modulating HOXC10/Cyclin D1 to inhibit gastric cancer progression

MicroRNAs (miRNAs) play important roles in posttranscriptional regulation and may serve as targets for the diagnosis and treatment of cancers. Nevertheless, a comprehensive understanding of miRNAs profiles in gastric cancer progression is still lacking. Here, we report that miR-129-5p is downregulated in gastric cancer by analyzing TCGA database (n = 41) and clinical tumor samples (n = 60). MiR-129-5p transfection suppressed gastric cancer cell proliferation through inducing G1 phase arrest in vitro and inhibit xenograft tumor growth in vivo. MiR-129-5p directly targeted the 3' untranslated regions (3' UTR) of HOXC10 mRNA and downregulated its expression. Importantly, miR-129-5p could reverse the oncogenic effect induced by HOXC10. We systemically screened the downstream target of HOXC10 by ChIP sequencing, and found that HOXC10 could transcriptionally regulate the expression of Cyclin D1 and facilitate G1/S cell cycle transition. Notably, high levels of HOXC10 and Cyclin D1 were related with poor prognosis of gastric cancer patients (n = 90). These findings reveal a novel role of miR-129-5p/HOXC10/Cyclin D1 axis in modulating cell cycle and gastric tumorigenesis, which might provide potential prognostic biomarkers and therapeutic targets for gastric cancer patients.

MicroRNA-129-5p represses the growth and aggressiveness of oral squamous cell carcinoma via suppressing HMGB1

Recent investigations have suggested that microRNA-129-5p (miR-129-5p) is commonly dysregulated in multiple types of malignancies. Nevertheless, the roles of miR-129-5p in human oral squamous cell carcinoma (OSCC) are not well explored. Herein, we demonstrated that miR-129-5p was down-expressed in OSCC cells and tissues. Moreover, miR-129-5p overexpression restrained the growth, migration ability, and invasiveness of OSCC cells. Notably, high-mobility group box 1 protein (HMGB1) was identified as a downstream target of miR-129-5p. Additional, knockdown of HMGB1 suppressed the growth and aggressive phenotypes of human OSCC cells. Importantly, re-expression of HMGB1 impaired the inhibitory impacts of miR-129-5p on the metastasis of OSCC cells. Altogether, these results implied that miR-129-5p restrained the aggressiveness of OSCC cells through modulating HMGB1.

[miR-34a-5p regulates viability, invasion and apoptosis of placental trophoblastic cells via modulating CDK6 and PI3K/AKT pathway]

OBJECTIVE

To investigate the roles of microRNA (miR)-34a-5p and cyclin-dependent kinase (CDK) 6 in the regulation of cell viability, apoptosis and invasion of human placental trophoblastic cells and the relationship between miR-34a-5p and CDK6.

METHODS

We examined the expression of miR-34a-5p using RT-qPCR in cultured human trophoblast HTR-8/Svneo cells and human choriocarcinoma cell lines BeWo and JEG-3HTR-8/Svneo. HTR-8/Svneo cells transfected with a miR-34a-5p-mimic, the miR-34a-5p-inhibitor, or pcDNA-CDK6 along with the mimic group were analyzed for changes in cell proliferation using MTT assay; the apoptosis of the cells were assessed by detecting caspase 3 activity and cleaved caspase 3 protein expression, and the cell invasion was evaluated using Transwell assay. Western blotting was used to determine the protein levels of CDK6, cleaved caspase 3, and MMP-9 in the cells. The interaction between CDK6 and miR-34a-5p analyzed using a luciferase reporter assay.

RESULTS

Transfection with the miR-34a-5p mimic significantly reduced the viability (P=0.000), suppressed the invasion (P=0.049), enhanced the cell apoptosis (P=0.018), down-regulated the expressions of MMP-9 (P=0.004) and CDK6 (P=0.014), and up-regulated caspase 3 activity (P=0.018) and cleaved caspase 3 expression (P=0.003) in cultured HTR-8/Svneo cells. CDK6 was confirmed as one of the target gene of miR-34a-5p. Transfection with pcDNA-CDK6 significantly reversed the effects of miR- 34a-5p overexpression on the cell viability (P=0.000), apoptosis (P=0.015), and invasion (P=0.046). Treatment of the cells with insulin-like growth factor 1 (IGF-1), an activator of the PI3K/AKT pathway, also significantly attenuated the effects of miR-34a- 5p overexpression on the cell viability (P=0.011), apoptosis (P=0.004), and invasion (P=0.002).

CONCLUSIONS

miR-34a-5p promotes apoptosis and inhibits the viability and invasion of human placental trophoblastic cells by down-regulating CDK6 and inactivating the PI3K/AKT pathway.

MiR-129-5p regulates cell proliferation and apoptosis via IGF-1R/Src/ERK/Egr-1 pathway in RA-fibroblast-like synoviocytes

It is reported that miR-129-5p plays an important role in various diseases, but its effect on rheumatoid arthritis (RA) and the potential mechanism remain to be clarified. In the present research, we aimed to investigate the effect of miR-129-5p on RA and the special molecular mechanism. First, the expression of miR-129-5p was analyzed in RA patients and RA Fibroblast-like synoviocytes (RA-FLSs) by RT-PCR assay. The cell viability, apoptotic rate and the relative expression of caspase-3 and caspase-8 were measured by CCK-8, Annexin-FITC/propidium iodide (PI) and ELISA, respectively. Luciferase reporter assay was performed to investigate the target of miR-129-5p. The results revealed that the expression of miR-129-5p was down-regulated in RA patients and RA-FLSs. In addition, miR-129-5p inhibited cell proliferation and induced apoptosis of RA-FLS. Furthermore, luciferase reporter assay demonstrated that insulin-like growth factor-1 receptor (IGF-1R) was the direct target of miR-129-5p, and IGF-1R promoted cell proliferation and inhibited apoptosis by activating Src/ERK/Egr-1 signaling. Furthermoremore, the Src/ERK/Egr-1 signaling pathway was suppressed by miR-129-5p. Collectively, the results of the present study suggested that miR-129-5p regulated cell proliferation and apoptosis via IGF-1R/Src/ERK/Egr-1 signaling pathway in RA.

MicroRNAs in non-small cell lung cancer: Gene regulation, impact on cancer cellular processes, and therapeutic potential

Lung cancer remains the most lethal cancer among men and women in the United States and worldwide. The majority of lung cancer cases are classified as non-small cell lung cancer (NSCLC). Developing new therapeutics on the basis of better understanding of NSCLC biology is critical to improve the treatment of NSCLC. MicroRNAs (miRNAs or miRs) are a superfamily of genome-derived, small noncoding RNAs that govern posttranscriptional gene expression in cells. Functional miRNAs are commonly dysregulated in NSCLC, caused by genomic deletion, methylation, or altered processing, which may lead to the changes of many cancer-related pathways and processes, such as growth and death signaling, metabolism, angiogenesis, cell cycle, and epithelial to mesenchymal transition, as well as sensitivity to current therapies. With the understanding of miRNA biology in NSCLC, there are growing interests in developing new therapeutic strategies, namely restoration of tumor suppressive miRNAs and inhibition of tumor promotive miRNAs, to combat against NSCLC. In this article, we provide an overview on the molecular features of NSCLC and current treatment options with a focus on pharmacotherapy and personalized medicine. By illustrating the roles of miRNAs in the control of NSCLC tumorigenesis and progression, we highlight the latest efforts in assessing miRNA-based therapies in animal models and discuss some critical challenges in developing RNA therapeutics.

Non-Coding RNA and Tumor Development in Neurofibromatosis Type 1: ANRIL Rs2151280 Is Associated with Optic Glioma Development and a Mild Phenotype in Neurofibromatosis Type 1 Patients

Non-coding RNAs (ncRNAs) are known to regulate gene expression at the transcriptional and post-transcriptional levels, chromatin remodeling, and signal transduction. The identification of different species of ncRNAs, microRNAs (miRNAs), circular RNAs (circRNAs), and long ncRNAs (lncRNAs)-and in some cases, their combined regulatory function on specific target genes-may help to elucidate their role in biological processes. NcRNAs' deregulation has an impact on the impairment of physiological programs, driving cells in cancer development. We here carried out a review of literature concerning the implication of ncRNAs on tumor development in neurofibromatosis type 1 (NF1), an inherited tumor predisposition syndrome. A number of miRNAs and a lncRNA has been implicated in NF1-associated tumors, such as malignant peripheral nerve sheath tumors (MPNSTs) and astrocytoma, as well as in the pathognomonic neurofibromas. Some authors reported that the lncRNA ANRIL was deregulated in the blood of NF1 patients with plexiform neurofibromas (PNFs), even if its role should be further elucidated. We here provided original data concerning the association of a specific genotype about ANRIL rs2151280 with the presence of optic gliomas and a mild expression of the NF1 phenotype. We also detected the LOH of ANRIL in different tumors from NF1 patients, supporting the involvement of ANRIL in some NF1-associated tumors. Our results suggest that ANRIL rs2151280 may be a potential diagnostic and prognostic marker, addressing early diagnosis of optic glioma and predicting the phenotype severity in NF1 patients.

A panel of noncoding RNAs in non-small-cell lung cancer

Non-small-lung cancer (NSCLC) is the leading cause of cancer death. Early detection of NSCLC could pave the way for effective therapies. Analysis of molecular genetic biomarkers in biological fluids has been proposed as a useful tool for cancer diagnosis. Here, we aimed to develop a panel of noncoding RNAs (ncRNAs) in sputum for NSCLC early detection. Expression of 11 ncRNAs were analyzed by real-time polymerase chain reaction in sputum samples of 30 NSCLC patients and 30 sex- and age-matched cancer-free controls. Stability of endogenous microRNAs (miRNAs) in sputum was evaluated after 3 and 6 days at 4°C, 6 months, and 1 year at -80°C. Nine ncRNAs showed significant differences of their expression in sputum between NSCLC patients and controls. A logistic regression model with the best prediction was built based on miR-145, miR-126, and miR-7. The composite of the three miRNAs produced 90% sensitivity and specificity in distinguishing NSCLC patients from the controls. Results indicate that miRNAs could be useful biomarkers based on their stability under various storage conditions and maintain differential changes between cancer and control groups. Moreover, measurement of miRNAs in sputum could be a noninvasive approach for detection of lung cancer.

Acute Spinal Cord Injury: A Systematic Review Investigating miRNA Families Involved

Acute traumatic spinal cord injury (SCI) involves primary and secondary injury mechanisms. The primary mechanism is related to the initial traumatic damage caused by the damaging impact and this damage is irreversible. Secondary mechanisms, which begin as early as a few minutes after the initial trauma, include processes such as spinal cord ischemia, cellular excitotoxicity, ionic dysregulation, and free radical-mediated peroxidation. SCI is featured by different forms of injury, investigating the pathology and degree of clinical diagnosis and treatment strategies, the animal models that have allowed us to better understand this entity and, finally, the role of new diagnostic and prognostic tools such as miRNA could improve our ability to manage this pathological entity. Autopsy could benefit from improvements in miRNA research: the specificity and sensitivity of miRNAs could help physicians in determining the cause of death, besides the time of death.

Chidamide-induced ROS accumulation and miR-129-3p-dependent cell cycle arrest in non-small lung cancer cells

BACKGROUND

Epigenetic therapy is a promising popular treatment modality for various cancers. Histone modification and miRNA should not be underestimated in lung cancer. This study aimed to investigate whether chidamide, a histone deacetylase inhibitor (HDACi), which inhibits telomerase activity and induces cell cycle arrest, influences ROS and miRNA production in non-small cell lung cancer (NSCLC) cells.

METHODS

H1355 and A549 were treated with chidamide. The analysis of DNA content was measured by FACSCalibur equipped with a 488 nm laser. H1355 cells were transfected with miR-129-3p mimic by Lipofectamine2000. Telomerase activity was performed on the telomeric repeat amplification protocol (TRAP) assay. Detection of thymidylate synthase (TS), p21, p53, pRB, and β-actin, were performed by western blot analysis.

RESULTS

Our data showed that expression of TS, p21, and pRB were altered in the presence of chidamide by PCR and western blot. Using BrdU-incorporation analysis, we found that chidamide induced G1 arrest through the regulation of the TS gene by miR-129-3p. Chidamide was shown to suppress telomerase activity in the TRAP assay and reduced the expression of human telomerase reverse transcriptase (hTERT) by PCR and q-PCR in H1355 and A549 cells. Chidamide increased the generation of reactive oxygen species (ROS) by flow cytometry. N-acetyl cysteine (NAC), a ROS scavenger, attenuated chidamide-induced telomerase activity inhibition.

CONCLUSION

Chidamide repressed telomerase activity through ROS accumulation and cell cycle arrest by miR-129-3p upregulation in both H1355 and A549 cells. This is the first study to demonstrate that chidamide induces miR-129-3p upregulation and ROS accumulation, leading to cell cycle arrest.

Hypomorphic mutation of the mouse Huntington's disease gene orthologue

Rare individuals with inactivating mutations in the Huntington's disease gene (HTT) exhibit variable abnormalities that imply essential HTT roles during organ development. Here we report phenotypes produced when increasingly severe hypomorphic mutations in the murine HTT orthologue Htt, (HdhneoQ20, HdhneoQ50, HdhneoQ111), were placed over a null allele (Hdhex4/5). The most severe hypomorphic allele failed to rescue null lethality at gastrulation, while the intermediate, though still severe, alleles yielded recessive perinatal lethality and a variety of fetal abnormalities affecting body size, skin, skeletal and ear formation, and transient defects in hematopoiesis. Comparative molecular analysis of wild-type and Htt-null retinoic acid-differentiated cells revealed gene network dysregulation associated with organ development that nominate polycomb repressive complexes and miRNAs as molecular mediators. Together these findings demonstrate that Htt is required both pre- and post-gastrulation to support normal development.

The tumor-suppressive function of miR-1296-5p by targeting EGFR and CDK6 in gastric cancer

We aimed to confirm the role of miR-1296-5p in gastric cancer and to identify its target genes. The expression of miR-1296-5p was measured in gastric cancer tissues and cell lines. The function of miR-1296-5p was examined by the overexpression and inhibition of its expression in typical gastric cell lines as well as SGC-7901 and MGC-803 cells. The targets of miR-1296-5p were identified by a luciferase activity assay. We found that miR-1296-5p was down-regulated in gastric cancer tissue and cell lines, and low expression levels of miR-1296-5p were associated with advanced clinical stage. Moreover, miR-1296-5p inhibited cell proliferation, migration, and invasion in SGC-7901 and MGC-803 cells. Then, we identified CDK6 and EGFR as novel targets of miR-1296-5p by a luciferase activity assay. Furthermore, the overexpression of miR-1296-5p suppressed the expression of CDK6 and EGFR. Our results indicated a tumor-suppressive role of miR-1296-5p through the translational repression of oncogenic CDK6 and EGFR in gastric cancer.

MicroRNA-129-5p is regulated by choline availability and controls EGF receptor synthesis and neurogenesis in the cerebral cortex

Choline availability modulates neurogenesis and cerebral cortex development through the regulation of neural progenitor cell (NPC) proliferative and differentiation capacity. In this study, we demonstrated that cortical NPC self-renewal is controlled by choline via the expression of a microRNA (miR-129-5p), whose role in the developing brain has not been examined, and which, in turn, inhibits synthesis of the epidermal growth factor receptor (EGFR) protein. Specifically, we found that low choline (LC) availability led to the upregulation of miR-129-5p expression in cortical NPCs in vitro and in vivo, causing the downregulation of EGFR and thereby disrupting NPC self-renewal and cortical neurogenesis. Furthermore, in response to LC availability, methylation potential (the S-adenosylmethionine: S-adenosylhomocysteine ratio) in the developing brain was reduced. Restoring methylation potential in LC cortical NPCs led to the re-establishment of normal miR-129-5p expression. We concluded that inhibiting miR-129-5p function and restoring EGFR protein levels in vivo is sufficient to reverse LC-induced defects in cortical NPC self-renewal. For the first time, to our knowledge, we have identified the molecular links that explain how a change in the availability of the diet metabolite choline impacts the essential cellular processes underlying brain development.-Trujillo-Gonzalez, I., Wang, Y., Friday, W. B., Vickers, K. C., Toth, C. L., Molina-Torres, L., Surzenko, N., Zeisel, S. H. MicroRNA-129-5p is regulated by choline availability and controls EGF receptor synthesis and neurogenesis in the cerebral cortex.

Epigenetic Regulation by lncRNAs: An Overview Focused on UCA1 in Colorectal Cancer

Colorectal cancers have become the second leading cause of cancer-related deaths. In particular, acquired chemoresistance and metastatic lesions occurring in colorectal cancer are a major challenge for chemotherapy treatment. Accumulating evidence shows that long non-coding (lncRNAs) are involved in the initiation, progression, and metastasis of cancer. We here discuss the epigenetic mechanisms through which lncRNAs regulate gene expression in cancer cells. In the second part of this review, we focus on the role of lncRNA Urothelial Cancer Associated 1 (UCA1) to integrate research in different types of cancer in order to decipher its putative function and mechanism of regulation in colorectal cancer cells. UCA1 is highly expressed in cancer cells and mediates transcriptional regulation on an epigenetic level through the interaction with chromatin modifiers, by direct regulation via chromatin looping and/or by sponging the action of a diversity of miRNAs. Furthermore, we discuss the role of UCA1 in the regulation of cell cycle progression and its relation to chemoresistance in colorectal cancer cells.

Molecular signatures of cytotoxic effects in human embryonic kidney 293 cells treated with single and mixture of ochratoxin A and citrinin

Ochratoxin A (OTA) and citrinin (CTN) are important mycotoxins, which often coexist in food and feed stuff. In this study, individual and combinative cytotoxicity of OTA and CTN were tested in human embryonic kidney (HEK) 293 cells via MTT assay, and synergistic cytotoxic effects were found following co-treatment with OTA and CTN, manifested by significant accumulation of HEK293 cells in S and G2/M stages. Transcriptomic and sRNA sequencing were performed to explore molecular signatures mediating individual or combinative cytotoxicity. A total of 378 miRNAs were identified, among which 66 miRNAs targeting thousands of genes were differentially expressed in response to different treatments, and 120 differentially expressed genes (DEGs) were regulated by either individual or combinative treatments. Correlations between two representative miRNAs (hsa-miR-1-3p and hsa-miR-122-5p), and their target genes, programmed cell death 10 (PDCD10) and cyclin G1 (CCNG1), associated with apoptotic signaling and cell cycle were analyzed by luciferase assay system. Further, their expression patterns were validated by quantitative real-time PCR and western blot analysis, suggesting that both miRNA-target interactions might account for the mycotoxin-induced cell death. Taken together, these findings provide molecular evidences for synergistic cytotoxic effects of exposure to single and mixture of OTA and CTN in HEK293 cells.

MicroRNA in lung cancer: role, mechanisms, pathways and therapeutic relevance

Lung cancer is the cardinal cause of cancer-related deaths with restricted recourse of therapy throughout the world. Clinical success of therapies is not very promising due to - late diagnosis, limited therapeutic tools, relapse and the development of drug resistance. Recently, small ∼20-24 nucleotides molecules called microRNAs (miRNAs) have come into the limelight as they play outstanding role in the process of tumorigenesis by regulating cell cycle, metastasis, angiogenesis, metabolism and apoptosis. miRNAs essentially regulate gene expression via post-transcriptional regulation of mRNA. Nevertheless, few studies have conceded the role of miRNAs in activation of gene expression. A large body of data generated by numerous studies is suggestive of their tumor-suppressing, oncogenic, diagnostic and prognostic biomarker roles in lung cancer. They have also been implicated in regulating cancer cell metabolism and resistance or sensitivity towards chemotherapy and radiotherapy. Further, miRNAs have also been convoluted in regulation of immune checkpoints - Programmed death 1 (PD-1) and its ligand (PD-L1). These molecules play a significant role in tumor immune escape leading to the generation of a microenvironment favouring tumor growth and progression. Therefore, it is imperative to explore the expression of miRNA and understand its relevance in lung cancer and development of anti-cancer strategies (anti - miRs, miR mimics and micro RNA sponges). In view of the above, the role of miRNA in lung cancer has been dissected and the associated mechanisms and pathways are discussed in this review.

Non-Coding RNAs in Endometrial Physiopathology

The Human Genome Project led to the discovery that about 80% of our DNA is transcribed in RNA molecules. Only 2% of the human genome is translated into proteins, the rest mostly produces molecules called non-coding RNAs, which are a heterogeneous class of RNAs involved in different steps of gene regulation. They have been classified, according to their length, into small non-coding RNAs and long non-coding RNAs, or to their function, into housekeeping non-coding RNAs and regulatory non-coding RNAs. Their involvement has been widely demonstrated in all cellular processes, as well as their dysregulation in human pathologies. In this review, we discuss the function of non-coding RNAs in endometrial physiology, analysing their involvement in embryo implantation. Moreover, we explore their role in endometrial pathologies such as endometrial cancer, endometriosis and chronic endometritis.

Effects of microRNA-129 and its target gene c-Fos on proliferation and apoptosis of hippocampal neurons in rats with epilepsy via the MAPK signaling pathway

This study aims to investigate the effect of microRNA-129 (miR-129) on proliferation and apoptosis of hippocampal neurons in epilepsy rats by targeting c-Fos via the MAPK signaling pathway. Thirty rats were equally classified into a model group (successfully established as chronic epilepsy models) and a normal group. Expression of miR-129, c-Fos, bax, and MAPK was detected by RT-qPCR and Western blotting. Hippocampal neurons were assigned into normal, blank, negative control (NC), miR-129 mimic, miR-129 inhibitor, siRNA-c-Fos, miR-129 inhibitor+siRNA-c-Fos groups. The targeting relationship between miR-129 and c-Fos was predicted and verified by bioinformatics websites and dual-luciferase reporter gene assay. Cell proliferation after transfection was measured by MTT assay, and cell cycle and apoptosis by flow cytometry. c-Fos is a potential target gene of miR-129. Compared with the normal group, the other six groups showed a decreased miR-129 expression; increased expression of expression of c-Fos, Bax, and MAPK; decreased proliferation; accelerated apoptosis; more cells arrested in the G1 phase; and fewer cells arrested in the S phase. Compared with the blank and NC groups, the miR-129 mimic group and the siRNA-c-Fos group showed decreased expression of c-Fos, Bax, and MAPK, increased cells proliferation, and decreased cell apoptosis, fewer cells arrested in the G1 phase and more cells arrested in the S phase. However, the miR-129 inhibitor groups showed reverse consequences. This study suggests that miR-129 could inhibit the occurrence and development of epilepsy by repressing c-Fos expression through inhibiting the MAPK signaling pathway.

Epigenetic silencing of tumor suppressor long non-coding RNA BM742401 in chronic lymphocytic leukemia

BM742401 is a tumor suppressor lncRNA downregulated in gastric cancer. As the promoter region and the entire transcript are embedded in a CpG island, we postulated that BM742401 is a tumor suppressor lncRNA inactivated by DNA methylation in chronic lymphocytic leukemia (CLL). The promoter of BM742401 was unmethylated in normal controls including three each of normal bone marrow, peripheral blood buffy coats, and CD19-sorted peripheral B-cells, but methylated in four (57.1%) CLL cell lines. Methylation of BM742401 correlated inversely with expression. In the completely methylated WAC3CD5+ CLL cells, 5-Aza-2′-deoxycytidine treatment led to promoter demethylation and re-expression of BM742401 transcript. Functionally, stable overexpression of BM742401 resulted in inhibition of cellular proliferation and enhanced apoptosis through caspase-9-dependent intrinsic but not caspase-8-dependent extrinsic apoptosis pathway, suggesting a tumor suppressor role of BM742401 in CLL. In primary CLL samples, methylation of BM742401 was detected in 43/98 (43.9%) of patients. Moreover, among CLL patients with standard-risk cytogenetic aberrations, methylation of BM742401 correlated with advanced Rai stage (≥ stage 2)(P = 0.002). Furthermore, BM742401 methylation was associated with miR-129-2 methylation (P = 0.05). BM742401 is a tumor suppressor lncRNA frequently methylated in CLL. The mechanism of BM742401 as a tumor suppressor warrants further studies.

Role of Microbiome in Carcinogenesis Process and Epigenetic Regulation of Colorectal Cancer

Epigenetic changes during the development of colorectal cancer (CRC) play a significant role. Along with factors such as diet, lifestyle, and genetics, oncogenic infection, bacteria alone or whole microbiome, has been associated with this tumor type. How gut microbiome contributes to CRC pathogenesis in the host is not fully understood. Most of the epigenetic studies in CRC have been conducted in populations infected with Helicobacter pylori. In the current review, we summarize how the gut microbiota contributes in colon carcinogenesis and the potential role of epigenetic mechanism in gene regulation. We discuss microbiota-mediated initiation and progression of colon tumorigenesis and have also touched upon the role of microbial metabolites as an initiator or an inhibitor for procarcinogenic or antioncogenic activities. The hypothesis of gut microbiota associated CRC revealed the dynamic and complexity of microbial interaction in initiating the development of CRC. In the multifaceted processes of colonic carcinogenesis, gradual alteration of microbiota along with their microenvironment and the potential oncopathogenic microbes mediated modulation of cancer therapy and other factors involved in microbiome dysbiosis leading to the CRC have also been discussed. This review provides a comprehensive summary of the mechanisms of CRC development, the role of microbiome or single bacterial infection in regulating the processes of carcinogenesis, and the intervention by novel therapeutics. Epigenetic mechanism involved in CRC is also discussed.

Circular RNA hsa_circ_000984 promotes colon cancer growth and metastasis by sponging miR-106b

Circular RNAs (circRNAs) as a novel type of noncoding RNAs (ncRNAs) are widely studied in the development of human various diseases, including cancer. Here, we found circular RNA hsa_circ_000984 encoded by the CDK6 gene was remarkably upregulated in the tissues of colorectal cancer (CRC) patients and in the CRC cell lines. Moreover, high expression level of hsa_circ_000984 was significantly associated with advanced colorectal cancer. Further analysis revealed that hsa_circ_000984 knockdown could inhibit cell proliferation, migration, invasion in vitro and tumor formation in vivo in CRC cell lines. Mechanically, we found that hsa_circ_000984 may act as a competing endogenous RNA (ceRNA) by competitively binding miR-106b and effectively upregulate the expression of CDK6, thereby inducing a series of malignant phenotypes of tumor cells. Taken together, these observations suggest that the hsa_circ_000984 could mediate the expression of gene CDK6 by acting as a ceRNA, which may contribute to a better understanding of between the regulatory miRNA network and CRC pathogenesis.

Cancer Hallmarks and MicroRNAs: The Therapeutic Connection

Human cancers are characterized by a number of hallmarks, including sustained proliferative signaling, evasion of growth suppressors, activated invasion and metastasis, replicative immortality, angiogenesis, resistance to cell death, and evasion of immune destruction. As microRNAs (miRNAs) are deregulated in virtually all human cancers, they show involvement in each of the cancer hallmarks as well. In this chapter, we describe the involvement of miRNAs in cancer from a cancer hallmarks and targeted therapeutics point of view. As no miRNA-based cancer therapeutics are available to date, and the only clinical trial on miRNA-based cancer therapeutics (MRX34) was terminated prematurely due to serious adverse events, we are focusing on protein-coding miRNA targets for which targeted therapeutics in oncology are already approved by the FDA. For each of the cancer hallmarks, we selected major protein-coding players and describe the miRNAs that target them.

Suberoylanilide hydroxamic acid induces thioredoxin1-mediated apoptosis in lung cancer cells via up-regulation of miR-129-5p

Histone deacetylase (HDAC) inhibitors, especially suberoylanilide hydroxamic acid (SAHA) induce apoptosis in various cancer cells. Here, we investigated the effect of SAHA on apoptosis in lung cancer cells and addressed the role of reactive oxygen species (ROS), glutathione (GSH), and thioredoxin1 (Trx1) levels in this process. We also identified the miRNAs that down-regulate Trx1 expression at RNA level and thereby influence apoptotic cell death of SAHA increased intracellular ROS levels and promoted apoptotic cell death in cancerous cells but not in non-cancerous normal lung cells. Likewise, SAHA induced GSH depletion specifically in cancerous cells. While N-acetyl cysteine (NAC) reduced ROS level and reversed the effect of SAHA on cell death, L-buthionine sulfoximine (BSO) further enhanced GSH depletion, and promoted cell death. SAHA decreased the mRNA and protein levels of Trx1 in lung cancer cells. Knockdown/suppression of Trx1 intensified apoptosis in SAHA-treated lung cancer cells whereas overexpression of Trx1 prevented the cell death in these cells. SAHA up-regulated the level of miR-129-5p, which binds to 3' untranslated region (3'UTR) of Trx1 and down-regulates Trx1 expression. Down-regulation of Trx1 led to activation of apoptosis-signal regulating kinase (ASK), which induced apoptotic cell death by triggering ASK-JNK or ASK-p38 kinase pathway. In conclusion, changes in ROS and GSH levels in SAHA-treated lung cancer cells partially co-related with cell death. SAHA induced apoptosis via the down-regulation of Trx1, which was regulated by miR-129-5p.

Involvement of Non-coding RNAs in the Signaling Pathways of Colorectal Cancer

Colorectal cancer (CRC) is one of the most common diagnosed cancers worldwide. The metastasis and development of resistance to anti-cancer treatment are major challenges in the treatment of CRC. Understanding mechanisms underpinning the pathogenesis is therefore critical in developing novel agents for CRC treatments. A large number of evidence has demonstrated that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs have functional roles in both the physiological and pathological processes by regulating the expression of their target genes. These molecules are engaged in the pathobiology of neoplastic diseases and are targets for the diagnosis, prognosis and therapy of a variety of cancers, including CRC. In this regard, ncRNAs have emerged as one of the hallmarks of CRC pathogenesis and they also play key roles in metastasis, drug resistance and the stemness of CRC stem cell by regulating various signaling networks. Therefore, a better understanding the ncRNAs involved in the signaling pathways of CRC may lead to the development of novel strategy for diagnosis, prognosis and treatment of CRC. In this chapter, we summarize the latest findings on ncRNAs, with a focus on miRNAs and lncRNAs involving in signaling networks and in the regulation of pathogenic signaling pathways in CRC.

MiR-129-5p influences the progression of gastric cancer cells through interacting with SPOCK1

The purpose of our study is to clarify the effect of microRNA-129-5p in the progression of human gastric cancer cells by regulating SPOCK1. The expression of microRNA-129-5p and SPOCK1 was tested by quantitative real-time polymerase chain reaction in tissues and cell lines. We validated the targeted relationship between microRNA-129-5p and SPOCK1 by dual luciferase reporter gene assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, flow cytometry, transwell, and wound scratch assays were used to analyze the effects of microRNA-129-5p on SGC-7901 cell viability, proliferation, cell cycle and apoptosis, invasiveness, and migration. MicroRNA-129-5p was downregulated while SPOCK1 was upregulated in gastric cancer tissues and cell lines. The result of luciferase reporter gene assay demonstrated that microRNA-129-5p can target SPOCK1 by binding to the 3'untranslated region. The overexpression of microRNA-129-5p or the inhibition of SPOCK1 inhibited SGC-7901 viability, proliferation, migration, and invasion while promoted cell cycle arrest in G0/G1 stage and cell apoptosis. Our results suggested that microRNA-129-5p could directly specifically suppress SPOCK1, which might be one of the potential mechanisms in inhibiting cell processes including viability, proliferation, cell mitosis, migration, and invasiveness of gastric cancer cells.

MicroRNA-129-5p inhibits 3T3-L1 preadipocyte proliferation by targeting G3BP1

MicroRNAs have been regarded to play a crucial role in the proliferation of different cell types including preadipocytes. In our study, we observed that miR-129-5p was down-regulated during 3T3-L1 preadipocyte proliferation, while the expression of G3BP1 showed a contrary tendency. 5-Ethynyl-2′-deoxyuridine (EdU) incorporation assay and flow cytometry showed that overexpression of miR-129-5p could bring about a reduction in S-phase cells and G2-phase arrest. Additional study indicated that miR-129-5p impaired cell cycle-related genes in 3T3-L1 preadipocytes. Importantly, it showed that miR-129-5p directly targeted the 3′UTR of G3BP1 and the expression of G3BP1 was inhibited by miR-129-5p mimic. Moreover, miR-129-5p mimic activated the p38 signaling pathway through up-regulating p38 and the phosphorylation level of p38. In a word, results in our study revealed that miR-129-5p suppressed preadipocyte proliferation via targeting G3BP1 and activating the p38 signaling pathway.

MiR-129-5p suppresses gastric cancer cell invasion and proliferation by inhibiting COL1A1

Gastric cancer (GC) is one of the most lethal cancers worldwide. In this study, we aimed to explore the role of miR-129-5p, a newly identified miR-129 member, in GC cells as well as the potential mechanism of action. The results of reverse transcription - qualitative polymerase chain reaction (RT-qPCR) and Western Blot showed that miR-129 was downregulated in GC cells compared with normal ones. Using MTT, colony formation, wound healing assay, and a Transwell assay, we evaluated the proliferation, migration, and invasion abilities of transfected cells, and confirmed miR-129-5p as a tumor suppressor in GC. After a microarray analysis comparing different gene expressions in miR-129-5p transfected SGC-7901 cells, COL1A1 was selected for biggest fold-change and potential target of miR-129-5p predicted by TargetScan. Measured by RT-qPCR and Western blot, COL1A1 turned out to be upregulated in GC tissues and cells. We further confirmed the targeting relationship between miR-129-5p and COL1A1 by dual luciferase assay. By manipulating the expression of COL1A1 in SGC-7901 cells, cell proliferation, migration, and invasion were examined and the tumor-promoting function of COL1A1 was validated. Moreover, co-transfection of miR-129-5p mimics and COL1A1 attenuated the tumor-promoting effects induced by a single-transfection of COL1A1, and miR-129-5p inhibitor counteracted the tumor-suppressing effects of COL1A1 siRNA. Collectively, the data demonstrate the important functions of the miR-129-5p-COL1A1 axis in GC: miR-129-5p suppresses GC cell proliferation, migration, and invasion, by selectively inhibiting COL1A1. This study provides new therapeutic targets for the clinical treatment of GC.

MicroRNA-1258: An invasion and metastasis regulator that targets heparanase in gastric cancer

Numerous microRNAs (miRNAs/miRs) are involved in suppressing or promoting the formation of cancer. However, to the best of our knowledge, the role of miRNA-1258 in gastric cancer (GC) has not previously been investigated. Our previous study demonstrated an increased expression of heparanase (HPSE) in GC tissues and HPSE-facilitated invasion and metastasis of GC cells. Consequently, in the present study, the function of miR-1258 in the invasion and metastasis of GC cells was investigated to determine whether miR-1258 is associated with GC through HPSE. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine miR-1258 expression in GC cell lines and tissues. A Transwell cell invasion assay and an MTT proliferation assay were used to investigate the effects of miR-1258 on the invasion and proliferation of one of the cell lines, SGC-7901 cells, in vitro. The effect of miR-1258 on SGC-7901 cell metastasis was investigated using an in vivo tumor metastasis formation assay. Western blot analysis and RT-qPCR were used to investigate whether HPSE was a target of miR-1258 in GC. The expression of miR-1258 was significantly downregulated in 3 GC cell lines and 116 GC tissues compared with controls (all P<0.001). An association was identified between decreased miR-1258 expression level and increased age (P=0.042), advanced pathological tumor stage (P=0.027) and positive lymphatic vessel invasion (P=0.044) in patients with GC. Furthermore, the upregulation of miR-1258 expression suppressed SGC-7901 cell invasion in vitro (P<0.001) and inhibited SGC-7901 cell metastasis in vivo (P=0.016). The western blot analysis and RT-qPCR results indicated that miR-1258 downregulated the expression of HPSE at the translational level. The results of the present study indicate that miR-1258 acts as a tumor suppressor to inhibit invasion and metastasis by targeting HPSE. Therefore, miR-1258 may serve as a novel biomarker and therapeutic target in the treatment of GC.

MicroRNA promoter methylation: a new tool for accurate detection of urothelial carcinoma

Background:

Urothelial carcinoma (UC) is the most common cancer affecting the urinary system, worldwide. Lack of accurate early detection tools entails delayed diagnosis, precluding more efficient and timely treatment. In a previous study, we found that miR-129-2 and miR-663a were differentially methylated in UC compared with other genitourinary tract malignancies. Here, we evaluated the diagnostic performance of those microRNAs in urine.

Methods:

Promoter methylation levels of miR-129-2 and miR-663a were assessed, using real-time quantitative methylation-specific PCR, in UC tissue samples (using normal urothelium as control) and, subsequently, in urine samples from UC and other genitourinary malignancies. Diagnostic and prognostic performances were evaluated by receiver operator characteristics curve and survival analyses, respectively.

Results:

Promoter methylation levels of both microRNAs were significantly higher in UC tissue samples compared with normal urothelium. In urine, the assay was able to distinguish UC from other genitourinary tract carcinomas with 87.7% sensitivity and 84% specificity, resulting in 85.85% overall accuracy.

Conclusions:

This panel of miRNAs promoter methylation accurately detects UC in urine, comparing well with other promising epigenetic-based biomarkers. This may constitute the basis for a non-invasive assay to detect UC.

Targeting CDK6 in cancer: State of the art and new insights

Cyclin-dependent kinase 6 (CDK6) plays a vital role in regulating the progression of the cell cycle. More recently, CDK6 has also been shown to have a transcriptional role in tumor angiogenesis. Up-regulated CDK6 activity is associated with the development of several types of cancers. While CDK6 is over-expressed in cancer cells, it has a low detectable level in non-cancerous cells and CDK6-null mice develop normally, suggesting a specific oncogenic role of CDK6, and that its inhibition may represent an ideal mechanism-based and low toxic therapeutic strategy in cancer treatment. Identification of selective small molecule inhibitors of CDK6 is thus needed for drug development. Herein, we review the latest understandings of the biological regulation and oncogenic roles of CDK6. The potential clinical relevance of CDK6 inhibition, the progress in the development of small-molecule CDK6 inhibitors and the rational design of potential selective CDK6 inhibitors are also discussed.

MicroRNA-320 family is downregulated in colorectal adenoma and affects tumor proliferation by targeting CDK6

AIM: To investigate the microRNA (miRNA) expression during histological progression from colorectal normal mucosa through adenoma to carcinoma within a lesion.

METHODS: Using microarray, the sequential changes in miRNA expression profiles were compared in colonic lesions from matched samples; histologically, non-neoplastic mucosa, adenoma, and submucosal invasive carcinoma were microdissected from a tissue sample. Cell proliferation assay was performed to observe the effect of miRNA, and its target genes were predicted using bioinformatics approaches and the expression profile of SW480 transfected with the miRNA mimics. mRNA and protein levels of the target gene in colon cancer cell lines with a mimic control or miRNA mimics were measured using qRT-PCR and Western blotting. The expression levels of miRNA and target gene in colorectal tissue samples were also measured.

RESULTS: Microarray analysis identified that the miR-320 family, including miR-320a, miR-320b, miR-320c, miR-320d and miR-320e, were differentially expressed in adenoma and submucosal invasive carcinoma. The miR-320 family, which inhibits cell proliferation, is frequently downregulated in colorectal adenoma and submucosal invasive carcinoma tissues. Seven genes including CDK6 were identified to be common in the results of gene expression array and bioinformatics analyses performed to find the target gene of the miR-320 family. We confirmed that mRNA and protein levels of CDK6 were significantly suppressed in colon cancer cell lines with miR-320 family mimics. CDK6 expression was found to increase from non-neoplastic mucosa through adenoma to submucosal invasive carcinoma tissues and showed an inverse correlation with miR-320 family expression.

CONCLUSION: MiR-320 family affects colorectal tumor proliferation by targeting CDK6, plays important role in its growth, and is considered to be a biomarker for its early detection.