DNA methylation-mediated repression of miR-941 enhances lysine (K)-specific demethylase 6B expression in hepatoma cells

Modulation of faecal miRNAs highlights the preventive effects of a Mediterranean low-inflammatory dietary intervention

BACKGROUND

Dietary interventions have been proposed as therapeutic approaches for several diseases, including cancer. A low-inflammatory Mediterranean dietary intervention, conducted as a pilot study in subjects with Familial Adenomatous Polyposis (FAP), reduced markers of local and systemic inflammation. We aim to determine whether this diet may modulate faecal microRNA (miRNA) and gene expression in the gut.

METHODS

Changes in the faecal miRNome were evaluated by small RNA sequencing at baseline (T0), after the three-month intervention (T1), and after an additional three months (T2). Changes in the transcriptome of healthy rectal mucosa and adenomas were evaluated by RNA sequencing at T0 and T2. The identification of validated miRNA-gene interactions and functional analysis of miRNA targets were performed using in silico approaches.

RESULTS

Twenty-seven subjects were included in this study. It was observed that the diet modulated 29 faecal miRNAs (p < 0.01; |log2 Fold Change|>1), and this modulation persisted for three months after the intervention. Levels of miR-3612-3p and miR-941 correlated with the adherence to the diet, miR-3670 and miR-4252-5p with faecal calprotectin, and miR-3670 and miR-6867 with serum calprotectin. Seventy genes were differentially expressed between adenoma and normal tissue, and most were different before the dietary intervention but reached similar levels after the diet. Functional enrichment analysis identified the proinflammatory ERK1/2, cell cycle regulation, and nutrient response pathways as commonly regulated by the modulated miRNAs and genes.

CONCLUSIONS

Faecal miRNAs modulated by the dietary intervention target genes that participate in inflammation. Changes in levels of miRNAs and genes with oncogenic and tumour suppressor functions further support the potential cancer-preventive effect of the low-inflammatory Mediterranean diet.

CLINICAL TRIAL NUMBER REGISTRATION

NCT04552405, Registered in ClinicalTrials.gov.

Comparative studies on in vitro antitumor activities and apoptosis-inducing effects of enantiomeric ruthenium(II) complexes

On the basis of our previous comparative studies on the DNA binding of a pair of ruthenium(II) complex enantiomers, Δ-[Ru(bpy)2PBIP]2+ and Λ-[Ru(bpy)2PBIP]2+ {bpy = 2,2'-bipyridine, PBIP = 2-(4-bromophenyl)imidazo[4,5-f]1,10-phenanthroline}, in this study, their antitumor activities and mechanisms were further investigated comparatively. The cytotoxicity assay demonstrated that both the enantiomers exerted selective antiproliferative effects on cancer cell lines A2780 and PC3. Fluorescence localization experiments suggested that both the enantiomers effectively permeated the nucleus of HeLa cells and co-localized with DNA, resulting in their DNA damage and apoptosis. Flow cytometry experiments showed that the apoptosis was enhanced by increasing the concentration of each enantiomer. Western blotting analyses indicated that both extrinsic and intrinsic apoptosis pathways were activated by the two enantiomers. miRNA microarray analyses displayed that both the enantiomers up- and downregulated multiple miRNAs, some of which were predicted to be associated with carcinogenesis. The above experimental results also showed that the Δ-enantiomer exerted a more potent antitumor activity, a higher efficiency of entering cancer cells and a stronger apoptosis-inducing effect compared with the Λ-enantiomer. Combined with the previously published research results, experimental results from this study implied that the antitumor activity of a metal complex might have originated from the conformation change of DNA in tumor cells caused by the intercalation of the complex, that the antitumor mechanism of a metal complex could be related to its DNA-binding mode, and that the antitumor efficiency of a metal complex could result from its DNA-binding strength.

EZH2-mediated epigenetic silencing of tumor-suppressive let-7c/miR-99a cluster by hepatitis B virus X antigen enhances hepatocellular carcinoma progression and metastasis

BACKGROUND

Hepatitis B virus (HBV)-encoded X antigen, HBx, assists in the development of hepatocellular carcinoma (HCC) through complex mechanisms. Our results provide new insights into the EZH2 epigenetic repression of let-7c that promotes HCC migration induced by HBx. Thus, let-7c and HMGA2 represent key diagnostic markers and potential therapeutic targets for the treatment of HBV-related HCC.

RESULTS

We investigated the epigenetic regulation of let-7c, an important representative miRNA in liver tumor metastasis, in human HCC cells to verify the effect of HBx. Based on quantitative PCR (qPCR) of mRNA isolated from tumor and adjacent non-tumor liver tissues of 24 patients with HBV-related HCC, EZH2 expression was significantly overexpressed in most HCC tissues (87.5%). We executed a miRNA microarray analysis in paired HBV-related HCC tumor and adjacent non-tumorous liver tissue from six of these patients and identified let-7c, miR-199a-3p, and miR-99a as being downregulated in the tumor tissue. Real-time PCR analysis verified significant downregulation of let-7c and miR-99a in both HepG2X and Hep3BX cells, which stably overexpress HBx, relative to parental cells. HBX enhanced EZH2 expression and attenuated let-7c expression to induce HMGA2 expression in the HCC cells. Knockdown of HMGA2 significantly downregulated the metastatic potential of HCC cells induced by HBx.

CONCLUSIONS

The deregulation of let-7c expression by HBx may indicate a potential novel pathway through deregulating cell metastasis and imply that HMGA2 might be used as a new prognostic marker and/or as an effective therapeutic target for HCC.

Exosomes from bone mesenchymal stem cells alleviate mifepristone-induced human endometrial stromal cell injury by inhibiting TLR3 via delivering miR-941

Objective

We aim to investigate the protective effect and underlying mechanisms of BMSCs-exo on human endometrial stromal cells (HESCs) induced by mifepristone in this study.

Methods

BMSCs-exo were extracted and then identified by transmission electron microscopy and western-blot assay. RT-PCR assay was used to determine the level of miR-941. MiR-941 mimics or inhibitor were transfected into BMSCs and the exosomes were extracted. Then, Cell activity, apoptosis rate, cell migration and invasion, as well as the expression of angiogenic proteins were determined in HESCs stimulated by mifepristone and BMSCs-exo. Next, Dual-luciferase reporting assay was used to verify the targeted binding of miR-941 to TLR3, and the TLR3 expression in HESCs was detected by RT-PCR and western-blot. Finally, TLR3 was overexpressed to evaluate the effects of miR-941 from BMSCs-exo on cell apoptosis, cell invasion and angiogenesis in HESCs induced by mifepristone.

Results

miR-941 was highly expressed in BMSCs-exo. Exosome miR-941 in BMSCs-exo inhibited the cell apoptosis, and promoted cell activity, cell migration, invasion as well as angiogenesis were also improved in HESCs induced by mifepristone. TLR3 was a target of miR-941, which was up-regulated in mifepristonetreated HESCs. We further found that miR-941 derived from BMSCs-exo down-regulated the expression of TLR3 in HESCs treated by mifepristone. In addition, TLR3 overexpression blocked the inhibition of miR-941 on mifepristone-induced cell apoptosis, as well as cell migration and angiogenesis in HESCs.

Conclusions

Thus, we concluded that BMSCs-exo has protective effect on mifepristone-induced cell damage by delivering miR-941 which targeted TLR3 and regulated cell activity, migration, and angiogenesis in HESCs.

The Mechanism Underlying the ncRNA Dysregulation Pattern in Hepatocellular Carcinoma and Its Tumor Microenvironment

HCC is one of the most common malignant tumors and has an extremely poor prognosis. Accumulating studies have shown that noncoding RNA (ncRNA) plays an important role in hepatocellular carcinoma (HCC) development. However, the details of the related mechanisms remain unclear. The heterogeneity of the tumor microenvironment (TME) calls for ample research with deep molecular characterization, with the hope of developing novel biomarkers to improve prognosis, diagnosis and treatment. ncRNAs, particularly microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), have been found to be correlated with HCC neogenesis and progression. In this review, we summarized the aberrant epigenetic and genetic alterations caused by dysregulated ncRNAs and the functional mechanism of classical ncRNAs in the regulation of gene expression. In addition, we focused on the role of ncRNAs in the TME in the regulation of tumor cell proliferation, invasion, migration, immune cell infiltration and functional activation. This may provide a foundation for the development of promising potential prognostic/predictive biomarkers and novel therapies for HCC patients.

Exome sequencing of hepatocellular carcinoma in lemurs identifies potential cancer drivers: A pilot study

Background and objectives

Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers in this group is unknown. Characterizing the genetic changes associated with hepatocellular carcinoma in prosimians may point to possible causes, treatments and methods of prevention, aiding conservation efforts that are particularly crucial to the survival of endangered lemurs. Although genomic studies of cancer in non-human primates have been hampered by a lack of tools, recent studies have demonstrated the efficacy of using human exome capture reagents across primates.

Methodology

In this proof-of-principle study, we applied human exome capture reagents to tumor-normal pairs from five lemurs with hepatocellular carcinoma to characterize the mutational landscape of this disease in lemurs.

Results

Several genes implicated in human hepatocellular carcinoma, including ARID1A, TP53 and CTNNB1, were mutated in multiple lemurs, and analysis of cancer driver genes mutated in these samples identified enrichment of genes involved with TP53 degradation and regulation. In addition to these similarities with human hepatocellular carcinoma, we also noted unique features, including six genes that contain mutations in all five lemurs. Interestingly, these genes are infrequently mutated in human hepatocellular carcinoma, suggesting potential differences in the etiology and/or progression of this cancer in lemurs and humans.

Conclusions and implications

Collectively, this pilot study suggests that human exome capture reagents are a promising tool for genomic studies of cancer in lemurs and other non-human primates.

Lay Summary

Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers is unknown. In this proof-of-principle study, we applied human DNA sequencing tools to tumor-normal pairs from five lemurs with hepatocellular carcinoma and compared the lemur mutation profiles to those of human hepatocellular carcinomas.

KDM6B (JMJD3) and its dual role in cancer

Epigenetic modifications play a fundamental role in the regulation of gene expression and cell fate. During the development of cancer, epigenetic modifications appear that favor cell proliferation and migration, but at the same time prevent differentiation and apoptosis, among other processes. KDM6B is a histone demethylase that specifically removes methyl groups from H3K27me3, thus allowing re-expression of its target genes. It is currently known that KDM6B can act as both a tumor suppressor and an oncogene depending on the cellular context. Therefore, in this work we summarize the current knowledge of the role that KDM6B plays in different oncological contexts, and we try to orient it towards its clinical application.

The Functions of the Demethylase JMJD3 in Cancer

Cancer is a major cause of death worldwide. Epigenetic changes in response to external (diet, sports activities, etc.) and internal events are increasingly implicated in tumor initiation and progression. In this review, we focused on post-translational changes in histones and, more particularly, the tri methylation of lysine from histone 3 (H3K27me3) mark, a repressive epigenetic mark often under- or overexpressed in a wide range of cancers. Two actors regulate H3K27 methylation: Jumonji Domain-Containing Protein 3 demethylase (JMJD3) and Enhancer of zeste homolog 2 (EZH2) methyltransferase. A number of studies have highlighted the deregulation of these actors, which is why this scientific review will focus on the role of JMJD3 and, consequently, H3K27me3 in cancer development. Data on JMJD3’s involvement in cancer are classified by cancer type: nervous system, prostate, blood, colorectal, breast, lung, liver, ovarian, and gastric cancers.

Adipose MSCs Suppress MCF7 and MDA-MB-231 Breast Cancer Metastasis and EMT Pathways Leading to Dormancy via Exosomal-miRNAs Following Co-Culture Interaction

Globally, breast cancer is the most frequently diagnosed cancer in women, and it remains a substantial clinical challenge due to cancer relapse. The presence of a subpopulation of dormant breast cancer cells that survived chemotherapy and metastasized to distant organs may contribute to relapse. Tumor microenvironment (TME) plays a significant role as a niche in inducing cancer cells into dormancy as well as involves in the reversible epithelial-to-mesenchymal transition (EMT) into aggressive phenotype responsible for cancer-related mortality in patients. Mesenchymal stem cells (MSCs) are known to migrate to TME and interact with cancer cells via secretion of exosome- containing biomolecules, microRNA. Understanding of interaction between MSCs and cancer cells via exosomal miRNAs is important in determining the therapeutic role of MSC in treating breast cancer cells and relapse. In this study, exosomes were harvested from a medium of indirect co-culture of MCF7-luminal and MDA-MB-231-basal breast cancer cells (BCCs) subtypes with adipose MSCs. The interaction resulted in different exosomal miRNAs profiles that modulate essential signaling pathways and cell cycle arrest into dormancy via inhibition of metastasis and epithelial-to-mesenchymal transition (EMT). Overall, breast cancer cells displayed a change towards a more dormant-epithelial phenotype associated with lower rates of metastasis and higher chemoresistance. The study highlights the crucial roles of adipose MSCs in inducing dormancy and identifying miRNAs-dormancy related markers that could be used to identify the metastatic pattern, predict relapses in cancer patients and to be potential candidate targets for new targeted therapy.

Circulating differential miRNAs profiling and expression in hexavalent chromium exposed electroplating workers

Hexavalent chromium [Cr (Ⅵ)] has extensive applications in industries, and long-term occupational exposure to Cr (Ⅵ) may lead to lung carcinoma and other cancers. While microRNA (miRNA) can take part in carcinogenesis, little is known about its expression profile in the population with Cr (Ⅵ) exposure. Thus, this study aimed to explore miRNA expression profiles in Cr (Ⅵ) exposed workers and to identify the potential biological function of differentially expressed miRNAs. A total of 45 significant differentially expressed miRNAs were identified by the miRNA array. The results of validation showed that miR-19a-3p, miR-19b-3p, and miR-142-3p were downregulated and miR-590-3p and miR-941 were upregulated in the exposure group. Multivariate analysis demonstrated that age, exposure duration and urinary chromium level were associated with one or more miRNAs expression. Target gene analysis indicated that these miRNAs might participate in the regulation of DNA damage-related signaling pathways. Taken together, Cr (Ⅵ) exposure can result in differential expression of miRNAs in occupational workers, and the expression of these miRNAs is correlated with the level and duration of Cr (Ⅵ) exposure, and the differentially expressed miRNAs may participate in DNA damage response.

The Role of Histone Acetylation-/Methylation-Mediated Apoptotic Gene Regulation in Hepatocellular Carcinoma

Epigenetics, an inheritable phenomenon, which influences the expression of gene without altering the DNA sequence, offers a new perspective on the pathogenesis of hepatocellular carcinoma (HCC). Nonalcoholic steatohepatitis (NASH) is projected to account for a significant share of HCC incidence due to the growing prevalence of various metabolic disorders. One of the major molecular mechanisms involved in epigenetic regulation, post-translational histone modification seems to coordinate various aspects of NASH which will further progress to HCC. Mounting evidence suggests that the orchestrated events of cellular and nuclear changes during apoptosis can be regulated by histone modifications. This review focuses on the current advances in the study of acetylation-/methylation-mediated histone modification in apoptosis and the implication of these epigenetic regulations in HCC. The reversibility of epigenetic alterations and the agents that can target these alterations offers novel therapeutic approaches and strategies for drug development. Further molecular mechanistic studies are required to enhance information governing these epigenetic modulators, which will facilitate the design of more effective diagnosis and treatment options.

MicroRNA-941 regulates the proliferation of breast cancer cells by altering histone H3 Ser 10 phosphorylation

Breast cancer including triple negative breast cancer (TNBC) represents an important clinical challenge, as these tumours often develop resistance to conventional chemotherapeutics. MicroRNAs play a crucial role in cell-cycle regulation, differentiation, apoptosis, and migration. Herein, we performed Affymetrix Gene Chip miRNA 4.0 microarray and observed differential regulation of miRNAs (75 upregulated and 199 downregulated) in metastatic MDA-MB-231 cells as compared to immortalized human non-tumorigenic breast epithelial (MCF-10A) cells. MicroRNA-941 was significantly upregulated in MDA-MB-231 cells (almost nine-fold increase) in comparison to MCF-10A cells. Transfection of MiRNA-941 inhibitor significantly decreased the proliferation and migration of MDA-MB-231 cells by altering the expressions of p21, Cyclin D1, PP2B-B1, E-cadherin and MMP-13. Interestingly, we provide first evidence that inhibiting miR-941 prevents cell proliferation and phosphorylation of histone H3 at Ser10 residue. Xenograft model of breast cancer was developed by subcutaneous injection of MDA-MB-231 cells into the mammary fat pad of female athymic nude mice (Crl:NU-Foxn1nu). The tumours were allowed to grow to around 60 mm³, thereafter which we divided the animals into seven groups (n = 5). Notably, intratumoral injection of miR-941 inhibitor significantly abolished the tumour growth in MDA-MB-231 xenograft model. 5-Fluorouracil (10 mg/kg, i.p.) was used as positive control in our study. To the best of our knowledge, we report for the first time that targeting miR-941 improves the sensitivity of MDA-MB-231 cells to 5-fluorouracil. This can be of profound clinical significance, as it provides novel therapeutic approach for treating variety of cancers (overexpressing miRNA-941) in general and breast cancers in particular.

Regulating Methylation at H3K27: A Trick or Treat for Cancer Cell Plasticity

Properly timed addition and removal of histone 3 lysine 27 tri-methylation (H3K27me3) is critical for enabling proper differentiation throughout all stages of development and, likewise, can guide carcinoma cells into altered differentiation states which correspond to poor prognoses and treatment evasion. In early embryonic stages, H3K27me3 is invoked to silence genes and restrict cell fate. Not surprisingly, mutation or altered functionality in the enzymes that regulate this pathway results in aberrant methylation or demethylation that can lead to malignancy. Likewise, changes in expression or activity of these enzymes impact cellular plasticity, metastasis, and treatment evasion. This review focuses on current knowledge regarding methylation and de-methylation of H3K27 in cancer initiation and cancer cell plasticity.

miR-495 and miR-5688 are down-regulated in non-small cell lung cancer under hypoxia to maintain interleukin-11 expression

Background

Hypoxia is a hallmark of cancer and is associated with poor prognosis. However, the molecular mechanism by which hypoxia promotes tumor progression remains unclear. MicroRNAs dysregulation has been shown to play a critical role in the tumor and tumor microenvironment. Here, we investigated the roles of miR‐495 and miR‐5688 in human non‐small cell lung cancer (NSCLC) and their underlying mechanism.

Methods

The expression levels of miR‐495 and miR‐5688 in human NSCLC tissue specimens were measured by quantitative real‐time polymerase chain reaction (qRT‐PCR). Deferoxamine (DFO) was used to determine whether the regulation of miR‐495 and miR‐5688 under hypoxia was dependent on hypoxia‐inducible factor 1‐alpha (HIF‐1α). Furthermore, the functions of miR‐495 and miR‐5688 in tumor progression were evaluated using colony formation, 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium (MTS), wound healing, transwell assays, and xenograft model. Two algorithms, PicTAR and Targetscan, were used to predict the target gene of these two miRNAs, and dual‐luciferase reporter assay was conducted to confirm the target. The unpaired two‐tailed t test, Pearson correlation analysis, and Fisher's exact probability test were performed for statistical analyses.

Results

Two miRNAs, miR‐495 and miR‐5688, were found to participate in NSCLC progression under hypoxia. They were down‐regulated in NSCLC tissues compared with normal tissues. We determined that hypoxia led to the down‐regulation of miR‐495 and miR‐5688 in NSCLC cells, which was independent of HIF‐1α and cellular metabolic energy. In addition, miR‐495 and miR‐5688 suppressed cell proliferation, migration, and invasion in vitro. The NSCLC xenograft model showed that miR‐495 and miR‐5688 inhibited tumor formation in vivo. Interestingly, we found that miR‐495 and miR‐5688 had the same target, interleukin‐11 (IL‐11). Recombinant human IL‐11 counteracted the effects of miR‐495 and miR‐5688 on NSCLC cells, suggesting that miR‐495 and miR‐5688 executed their tumor suppressive role by repressing IL‐11 expression.

Conclusion

We found that hypoxia down‐regulated the expression levels of miR‐495 and miR‐5688 in NSCLC to enhance IL‐11 expression and tumor progression, indicating that the miR‐495/miR‐5688/IL‐11 axis may serve as a therapeutic target and potential biomarker for NSCLC.

Serum Exosomal miR-941 as a promising Oncogenic Biomarker for Laryngeal Squamous Cell Carcinoma

At present, no blood-based biomarkers have been used in clinical practice for laryngeal squamous cell carcinoma (LSCC). Increasing evidence suggests that circulating exosomal microRNAs (miRNAs) may serve as potential diagnostic biomarkers for various cancers. This study aims to identify and evaluate serum exosomal miRNAs for LSCC diagnosis. The ExoQuick solution (EQ), which provides a high-yield and is a highly efficient exosome isolation method, was selected to isolate serum exosomes in the current study. In LSCC samples, exosome concentrations were higher than in healthy control (HC) samples. RNA-seq analysis identified a total of 1608 miRNAs, with 34 upregulated and 41 downregulated in LSCC samples relative to HC samples. Furthermore, qRT-PCR showed that miR-941 is significantly upregulated in LSCC serum exosomes, with this same trend seen in LSCC tissues and cells. Moreover, when examining miR-941 in cell lines, miR-941 overexpression promoted proliferation and invasion, while miR-941 knockdown inhibited cell proliferation and invasion. ROC curve analysis showed that miR-941 has an area under the curve (AUC) of 0.797 (95% CI = 0.676-0.918) for distinguishing LSCC patients from HCs. In conclusion, serum exosomal miR-941 may serve as a promising oncogenic biomarker for diagnosing LSCC, and has the potential as a therapeutic target.

Keap1-targeting microRNA-941 protects endometrial cells from oxygen and glucose deprivation-re-oxygenation via activation of Nrf2 signaling

BACKGROUND

Mimicking ischemia-reperfusion injury, oxygen and glucose deprivation (OGD)-re-oxygenation (OGDR) applied to endometrial cells produces significant oxidative stress and programmed necrosis, which can be inhibited by nuclear-factor-E2-related factor 2 (Nrf2) signaling. MicroRNA (miRNA)-induced repression of Keap1, a Nrf2 suppressor protein that facilitates Nrf2 degradation, is novel strategy to activate Nrf2 cascade.

METHODS

MicroRNA-941 (miR-941) was exogenously expressed in HESC and primary human endometrial cells, and the Nrf2 pathway examined by Western blotting and real-time quantitative PCR analysis. The endometrial cells were treated with OGDR, cell programmed necrosis and apoptosis were tested.

RESULTS

MiR-941 is a novel Keap1-targeting miRNA that regulates Nrf2 activity. In T-HESC cells and primary human endometrial cells, ectopic overexpression of miR-941 suppressed Keap1 3'-UTR (untranslated region) expression and downregulated its mRNA/protein expression, leading to activation of the Nrf2 cascade. Conversely, inhibition of miR-941 elevated Keap1 expression and activity in endometrial cells, resulting in suppression of Nrf2 activation. MiR-941 overexpression in endometrial cells attenuated OGDR-induced oxidative stress and programmed necrosis, whereas miR-941 inhibition enhanced oxidative stress and programmed necrosis. MiR-941 overexpression and inhibition were completely ineffective in Keap1-/Nrf2-KO T-HESC cells (using CRISPR/Cas9 strategy). Restoring Keap1 expression, using an UTR-depleted Keap1 construct, abolished miR-941-induced anti-OGDR activity in T-HESC cells. Thus Keap1-Nrf2 cascade activation is required for miR-941-induced endometrial cell protection.

CONCLUSIONS

Targeting Keap1 by miR-941 activates Nrf2 cascade to protect human endometrial cells from OGDR-induced oxidative stress and programmed necrosis. Video Abstract.

miR-639 Expression Is Silenced by DNMT3A-Mediated Hypermethylation and Functions as a Tumor Suppressor in Liver Cancer Cells

Emerging evidence has indicated that abnormal methylation of DNA contributes to hepatocarcinogenesis. However, the regulatory mechanisms are not well known. Here, we revealed that microRNA-639 (miR-639) expression is downregulated in liver cancer tissues and cells. The repression of miR-639 expression was attributed to hypermethylation in its promoter region, and DNA methyltransferase (DNMT3A) was found to mediate this hypermethylation. Repression of miR-639 expression promoted cell growth and migration/invasion in vitro and the growth of tumors in xenograft mouse models. Furthermore, miR-639 bound to the 3' UTR of both MYST2 and ZEB1 and suppressed their expression. MYST2 promoted the growth of liver cancer cells and ZEB1 facilitated the migration/invasion of liver cancer cells. Ectopic expression of MYST2 and ZEB1 counteracted the repression of malignancy induced by miR-639, which coincided with the reciprocal correlation between miR-639 and MYST2 and ZEB1 expression in clinical hepatocellular carcinoma (HCC) tissues. Thus, DNMT3A-mediated hypermethylation suppressed miR-639 expression, derepressing the expression of MSYT2 and ZEB1, which promoted tumorigenesis of liver cancer. These findings may shed light on the mechanism of abnormal expression of miRNAs involved in the malignancy of liver cancer and provide new biomarkers for liver cancer.

The role and prospect of JMJD3 in stem cells and cancer

Currently, stem cells are reported to be involved in tumor formation, drug resistance and recurrence. Inhibiting the proliferation of tumor cells, promoting their senescence and apoptosis has been the most important anti-tumor therapy. Epigenetics is involved in the regulation of gene expression and is closely related to cancer and stem cells. It mainly includes DNA methylation, histone modification, and chromatin remodeling. Histone methylation and demethylation play an important role in histone modification. Histone 3 lysine 27 trimethylation (H3K27me3) induces transcriptional inhibition and plays an important role in gene expression. Jumonji domain-containing protein-3 (JMJD3), one of the demethyases of histone H3K27me3, has been reported to be associated with the prognosis of many cancers and stem cells differentiation. Inhibition of JMJD3 can reduce proliferation and promote apoptosis in tumor cells, as well as suppress differentiation in stem cells. GSK-J4 is an inhibitor of demethylase JMJD3 and UTX, which has been shown to possess anti-cancer and inhibition of embryonic stem cells differentiation effects. In this review, we examine how JMJD3 regulates cellular fates of stem cells and cancer cells and references were identified through searches of PubMed, Medline, Web of Science.

Epigenetic Metalloenzymes

Epigenetics controls the expression of genes and is responsible for cellular phenotypes. The fundamental basis of these mechanisms involves in part the post-translational modifications (PTMs) of DNA and proteins, in particular, the nuclear histones. DNA can be methylated or demethylated on cytosine. Histones are marked by several modifications including acetylation and/or methylation, and of particular importance are the covalent modifications of lysine. There exists a balance between addition and removal of these PTMs, leading to three groups of enzymes involved in these processes: the writers adding marks, the erasers removing them, and the readers able to detect these marks and participating in the recruitment of transcription factors. The stimulation or the repression in the expression of genes is thus the result of a subtle equilibrium between all the possibilities coming from the combinations of these PTMs. Indeed, these mechanisms can be deregulated and then participate in the appearance, development and maintenance of various human diseases, including cancers, neurological and metabolic disorders. Some of the key players in epigenetics are metalloenzymes, belonging mostly to the group of erasers: the zinc-dependent histone deacetylases (HDACs), the iron-dependent lysine demethylases of the Jumonji family (JMJ or KDM) and for DNA the iron-dependent ten-eleven-translocation enzymes (TET) responsible for the oxidation of methylcytosine prior to the demethylation of DNA. This review presents these metalloenzymes, their importance in human disease and their inhibitors.

Recently Evolved Tumor Suppressor Transcript TP73-AS1 Functions as Sponge of Human-Specific miR-941

MicroRNA (miRNA) sponges are vital components of posttranscriptional gene regulation. Yet, only a limited number of miRNA sponges have been identified. Here, we show that the recently evolved noncoding tumor suppressor transcript, antisense RNA to TP73 gene (TP73-AS1), functions as a natural sponge of human-specific miRNA miR-941. We find unusually nine high-affinity miR-941 binding sites clustering within 1 kb region on TP73-AS1, which forms miR-941 sponge region. This sponge region displays increased sequence constraint only in humans, and its formation can be traced to the tandem expansion of a 71-nt-long sequence containing a single miR-941 binding site in old world monkeys. We further confirm TP73-AS1 functions as an efficient miR-941 sponge based on massive transcriptome data analyses, wound-healing assay, and Argonaute protein immunoprecipitation experiments conducted in cell lines. The expression of miR-941 and its sponge correlate inversely across multiple healthy and cancerous tissues, with miR-941 being highly expressed in tumors and preferentially repressing tumor suppressors. Thus, the TP73-AS1 and miR-941 duo represents an unusual case of the extremely rapid evolution of noncoding regulators controlling cell migration, proliferation, and tumorigenesis.

Epigenetic Modifications of the Liver Tumor Cell Line HepG2 Increase Their Drug Metabolic Capacity

Although human liver tumor cells have reduced metabolic functions as compared to primary human hepatocytes (PHH) they are widely used for pre-screening tests of drug metabolism and toxicity. The aim of the present study was to modify liver cancer cell lines in order to improve their drug-metabolizing activities towards PHH. It is well-known that epigenetics is strongly modified in tumor cells and that epigenetic regulators influence the expression and function of Cytochrome P450 (CYP) enzymes through altering crucial transcription factors responsible for drug-metabolizing enzymes. Therefore, we screened the epigenetic status of four different liver cancer cell lines (Huh7, HLE, HepG2 and AKN-1) which were reported to have metabolizing drug activities. Our results showed that HepG2 cells demonstrated the highest similarity compared to PHH. Thus, we modified the epigenetic status of HepG2 cells towards 'normal' liver cells by 5-Azacytidine (5-AZA) and Vitamin C exposure. Then, mRNA expression of Epithelial-mesenchymal transition (EMT) marker SNAIL and CYP enzymes were measured by PCR and determinate specific drug metabolites, associated with CYP enzymes by LC/MS. Our results demonstrated an epigenetic shift in HepG2 cells towards PHH after exposure to 5-AZA and Vitamin C which resulted in a higher expression and activity of specific drug metabolizing CYP enzymes. Finally, we observed that 5-AZA and Vitamin C led to an increased expression of Hepatocyte nuclear factor 4α (HNF4α) and E-Cadherin and a significant down regulation of Snail1 (SNAIL), the key transcriptional repressor of E-Cadherin. Our study shows, that certain phase I genes and their enzyme activities are increased by epigenetic modification in HepG2 cells with a concomitant reduction of EMT marker gene SNAIL. The enhancing of liver specific functions in hepatoma cells using epigenetic modifiers opens new opportunities for the usage of cell lines as a potential liver in vitro model for drug testing and development.

The Epigenetic Regulation of HCC Metastasis

Epigenetic alterations, such as histone modification, DNA methylation, and miRNA-mediated processes, are critically associated with various mechanisms of proliferation and metastasis in several types of cancer. To overcome the side effects and limited effectiveness of drugs for cancer treatment, there is a continuous need for the identification of more effective drug targets and the execution of mechanism of action (MOA) studies. Recently, epigenetic modifiers have been recognized as important therapeutic targets for hepatocellular carcinoma (HCC) based on their reported abilities to suppress HCC metastasis and proliferation in both in vivo and in vitro studies. Therefore, here, we introduce epigenetic modifiers and alterations related to HCC metastasis and proliferation, and their molecular mechanisms in HCC metastasis. The existing data suggest that the study of epigenetic modifiers is important for the development of specific inhibitors and diagnostic targets for HCC treatment.

Functional Role of Non-Coding RNAs during Epithelial-To-Mesenchymal Transition

Epithelial-to-mesenchymal transition (EMT) is a key biological process involved in a multitude of developmental and pathological events. It is characterized by the progressive loss of cell-to-cell contacts and actin cytoskeletal rearrangements, leading to filopodia formation and the progressive up-regulation of a mesenchymal gene expression pattern enabling cell migration. Epithelial-to-mesenchymal transition is already observed in early embryonic stages such as gastrulation, when the epiblast undergoes an EMT process and therefore leads to the formation of the third embryonic layer, the mesoderm. Epithelial-to-mesenchymal transition is pivotal in multiple embryonic processes, such as for example during cardiovascular system development, as valve primordia are formed and the cardiac jelly is progressively invaded by endocardium-derived mesenchyme or as the external cardiac cell layer is established, i.e., the epicardium and cells detached migrate into the embryonic myocardial to form the cardiac fibrous skeleton and the coronary vasculature. Strikingly, the most important biological event in which EMT is pivotal is cancer development and metastasis. Over the last years, understanding of the transcriptional regulatory networks involved in EMT has greatly advanced. Several transcriptional factors such as Snail, Slug, Twist, Zeb1 and Zeb2 have been reported to play fundamental roles in EMT, leading in most cases to transcriptional repression of cell⁻cell interacting proteins such as ZO-1 and cadherins and activation of cytoskeletal markers such as vimentin. In recent years, a fundamental role for non-coding RNAs, particularly microRNAs and more recently long non-coding RNAs, has been identified in normal tissue development and homeostasis as well as in several oncogenic processes. In this study, we will provide a state-of-the-art review of the functional roles of non-coding RNAs, particularly microRNAs, in epithelial-to-mesenchymal transition in both developmental and pathological EMT.

Therapeutic targeting of noncoding RNAs in hepatocellular carcinoma: Recent progress and future prospects

Due to the high mortality rate and unsatisfactory treatment options available, hepatocellular carcinoma (HCC) remains one of the most common malignancies and a leading cause of cancer-associated mortality. Novel therapeutic targets for HCC are urgently required. Advanced RNA sequencing technology enables the identification of considerable amounts of noncoding RNAs (ncRNAs), including small noncoding RNAs and long noncoding RNAs, which exhibit no protein-coding activities. In this respect, ncRNAs and their regulatory processes are important factors in liver tumorigenesis. The present review focuses on the characteristics and biological roles of ncRNAs in HCC. Potential therapeutic applications of ncRNAs in HCC are also evaluated.

Genome-wide integrative analysis identified SNP-miRNA-mRNA interaction networks in peripheral blood mononuclear cells

AIM

To detect SNP-miRNA-mRNA interaction networks and to elucidate miRNA-mediated regulation effects on mRNA expression.

MATERIALS & METHODS

In human peripheral blood mononuclear cells of 43 females, SNP-miRNA-mRNA interaction networks were established through an integrative analysis. Then causal inference test was followed to detect miRNA-mediated effects on mRNA expressions.

RESULTS

About 167 trios corresponding to 56 SNPs, 20 miRNAs and 47 target-mRNAs have the SNP-miRNA-mRNA interactions, but only 22 trios have miRNA-mediated effects between SNP and mRNA. For the three miRNAs (hsa-miR-222-3p, hsa-miR-181b-5p and hsa-miR-106b-5p), each mediates at least four correlations between SNP and mRNA. The mRNAs in interaction play an important role in energy metabolism, cellular and tissue homeostasis.

CONCLUSION

This study represents the first effort of constructing an integrative interaction network of SNP-miRNA-mRNA and miRNA-mediated regulatory effects that provide helpful clues for future investigations of peripheral blood mononuclear cell-related physiological process and immunological diseases.

miR-941 as a promising biomarker for acute coronary syndrome

BACKGROUND

Circulating miRNAs can function as biomarkers for diagnosis, treatment, and prevention of diseases. However, it is unclear whether miRNAs can be used as biomarkers for acute coronary syndrome (ACS). To this end, we applied gene chip technology to analyze miRNA expression in patients with stable angina (SA), non-ST elevation ACS (NSTE-ACS), and ST-segment elevation myocardial infarction (STEMI).

METHODS

We enrolled patients with chest pain who underwent diagnostic coronary angiography, including five patients each with SA, NSTE-ACS, or STEMI, and five controls without coronary artery disease (CAD) but with three or more risk factors. After microarray analysis, differential miRNA expression was confirmed by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR).

RESULTS

Compared with those in patients with STEMI, differentially expressed microRNAs in controls and patients with SA or NSTE-ACS were involved in inflammation, protein phosphorylation, and cell adhesion. Pathway analysis showed that differentially expressed miRNAs were related to the mitogen-activated protein kinase signaling, calcium ion pathways, and cell adhesion pathways. Compared with their expression levels in patients with STEMI, miR-941, miR-363-3p, and miR-182-5p were significantly up-regulated (fold-change: 2.0 or more, P < 0.05) in controls and patients with SA or NSTE-ACS. Further, qRT-PCR showed that plasma miR-941 level was elevated in patients with NSTE-ACS or STEMI as compared with that in patients without CAD (fold-change: 1.65 and 2.28, respectively; P < 0.05). Additionally, miR-941 expression was significantly elevated in the STEMI group compared with that in the SA (P < 0.01) and NSTE-ACS groups (P < 0.05). Similarly, miR-941 expression was higher in patients with ACS (NSTE-ACS or STEMI) than in patients without ACS (without CAD or with SA; P < 0.01). There were no significant differences in miR-182-5p and miR-363-3p expression. The areas under the receiver operating characteristic curves were 0.896, 0.808, and 0.781 for patients in the control, SA, and NSTE-ACS groups, respectively, compared with that for patients with STEMI; that for the ACS group compared with the non-ACS group was 0.734.

CONCLUSION

miR-941 expression was relatively higher in patients with ACS and STEMI. Thus, miR-941 may be a potential biomarker of ACS or STEMI.

LncRNA-SARCC suppresses renal cell carcinoma (RCC) progression via altering the androgen receptor(AR)/miRNA-143-3p signals

While the androgen receptor (AR) might promote renal cell carcinoma (RCC) initiation and progression, the molecular mechanisms involved remain largely unclear. Here, we discovered the novel LncRNA-SARCC, which was suppressed and associated with better prognosis in RCC. Preclinical studies using multiple RCC cells and in vivo mouse model indicated that LncRNA-SARCC could attenuate RCC cell invasion, migration and proliferation in vitro and in vivo. Mechanistically, LncRNA-SARCC bound and destabilized AR protein with an inhibition of AR function, which led to transcriptionally de-repress miR-143-3p expression, thus inhibition of its downstream signals including AKT, MMP-13, K-RAS and P-ERK. In addition, bisulfite sequencing analysis substantiated that LncRNA-SARCC promoter was highly methylated in renal cancer tissues compared with paired non-cancerous renal tissues. Notably, treating with Sunitinib, the multi-targeted receptor tyrosine kinase inhibitor, increased the expression of LncRNA-SARCC, which decreased RCC cells resistance to Sunitinib. Thus, our study presented a road map for targeting this newly identified LncRNA-SARCC and its pathway, which expands potential therapeutic strategies for RCC treatment.

Upregulation of kazrin F by miR-186 suppresses apoptosis but promotes epithelial-mesenchymal transition to contribute to malignancy in human cervical cancer cells

Objective

Previous studies have identified that kazrin is a constituent of desmosome and influences intercellular adhesion, growing development and morphology. We previously cloned another new isoform, kazrin F and found that it has anti-apoptotic effects on human glioma cell line. To further explore whether kazrin F is involved in tumorigenesis, we investigated its expression and role in cervical cancer (CC) cells.

Methods

The role of kazrin F and miR-186 in CC was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation, transwell, and apoptosis assays. Using enhanced green fluorescent protein (EGFP) reporter assays, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, we identified kazrin F post-transcriptional regulation by miR-186.

Results

We demonstrate that kazrin F is highly expressed in CC tissues compared with the adjacent noncancerous tissues and promotes cell proliferation, colony formation, migration and invasion in HeLa and C33A cells by suppressing apoptosis and facilitating epithelial-to-mesenchymal transition (EMT). Furthermore, miR-186 was confirmed as a regulator of kazrin F dysregulation. An EGFP reporter assay proved that miR-186 directly targets the 3’-untranslated region (3’UTR) of kazrin F and downregulates its expression, and miR-186 expression showed an inverse correlation with kazrin F levels in CC tissues. In addition, overexpression of miR-186 suppressed the malignant behaviors of CC cells. The ectopic expression of kazrin F rescued the inhibitory effects of miR-186.

Conclusions

Our findings indicate that the upregulation of kazrin F due to downregulated miR-186 levels contributes to malignancy, and highlight the significance of kazrin F in CC tumorigenesis.

MicroRNA-941 Expression in Polymorphonuclear Granulocytes Is Not Related to Granulomatosis with Polyangiitis

Jumonji Domain-Containing Protein 3 (JMJD3)/lysine demethylase 6B (KDM6B) is an epigenetic modulator that removes repressive histone marks on genes. Expression of KDM6B mRNA is elevated in leukocytes from patients with ANCA-associated vasculitis (AAV) and has been suggested to be the reason for higher proteinase 3 (PR3) mRNA expression in these cells due to derepression of PRTN3 gene transcription. MicroRNA-941 (miR-941) has been shown to target KDM6B mRNA and inhibit JMJD3 production. We therefore investigated whether polymorphonuclear granulocytes (PMNs) from patients suffering from granulomatosis with polyangiitis (GPA) have lower expression of miR-941 than healthy control donors as a biological cause for higher JMJD3 levels. We found no significant difference in the degree of maturation of PMNs from GPA patients (n = 8) and healthy controls (n = 11) as determined from cell surface expression of the neutrophil maturation marker CD16 and gene expression profile of FCGR3B. The expression of PRTN3 and KDM6B mRNAs and miR-941 was not significantly different in GPA patients and healthy controls. Transfection of pre-miR-941 into the neutrophil promyelocyte cell line PLB-985 cells did not result in reduction of the KDM6B mRNA level as shown previously in a hepatocellular carcinoma cell line. The amount of PR3 in PMNs from GPA patients and healthy controls was comparable. In conclusion, we found that PRTN3 mRNA, KDM6B mRNA, and miR-941 expression levels in PMNs do not differ between GPA patients and healthy controls, and that miR-941 does not uniformly regulate KDM6B mRNA levels by inducing degradation of the transcript. Thus, decreased miR-941 expression in PMNs cannot be part of the pathogenesis of GPA.

Jumonji histone demethylases as emerging therapeutic targets

The methylation status of lysine residues in histones determines the transcription of surrounding genes by modulating the chromatin architecture. Jumonji domain-containing histone-lysine demethylases (Jmj-KDMs) remove the methyl moiety from lysine residues in histones by utilizing Fe(2+) and α-ketoglutarate. Since genetic alterations in Jmj-KDMs occur in various human cancers, the roles of Jmj-KDMs in cancer development and progression have been investigated, but still controversial. The KDM7 subfamily, which belongs to the Jmj-KDM family, is an emerging class of transcriptional coactivators because its members erase the repressive marks H3K9me2/1, H3K27me2/1, and H4K20 me1. Recently, KDM7C (alternatively named PHF2) was discovered as a new KDM7 member and identified to play a tumor-suppressive role through the reinforcement of p53-driven growth arrest and apoptosis. In this article, we generally reviewed the roles of Jmj-KDMs in human cancers and more discussed the molecular functions and the clinical significances of KDM7C.

H3K27 Demethylase JMJD3 Employs the NF-κB and BMP Signaling Pathways to Modulate the Tumor Microenvironment and Promote Melanoma Progression and Metastasis

Histone methylation is a key epigenetic mark that regulates gene expression. Recently, aberrant histone methylation patterns caused by deregulated histone demethylases have been associated with carcinogenesis. However, the role of histone demethylases, particularly the histone H3 lysine 27 (H3K27) demethylase JMJD3, remains largely uncharacterized in melanoma. Here, we used human melanoma cell lines and a mouse xenograft model to demonstrate a requirement for JMJD3 in melanoma growth and metastasis. Notably, in contrast with previous reports examining T-cell acute lymphoblastic leukemia and hepatoma cells, JMJD3 did not alter the general proliferation rate of melanoma cells in vitro. However, JMJD3 conferred melanoma cells with several malignant features such as enhanced clonogenicity, self-renewal, and transendothelial migration. In addition, JMJD3 enabled melanoma cells not only to create a favorable tumor microenvironment by promoting angiogenesis and macrophage recruitment, but also to activate protumorigenic PI3K signaling upon interaction with stromal components. Mechanistic investigations demonstrated that JMJD3 transcriptionally upregulated several targets of NF-κB and BMP signaling, including stanniocalcin 1 (STC1) and chemokine (C-C motif) ligand 2 (CCL2), which functioned as downstream effectors of JMJD3 in self-renewal and macrophage recruitment, respectively. Furthermore, JMJD3 expression was elevated and positively correlated with that of STC1 and CCL2 in human malignant melanoma. Moreover, we found that BMP4, another JMJD3 target gene, regulated JMJD3 expression via a positive feedback mechanism. Our findings reveal a novel epigenetic mechanism by which JMJD3 promotes melanoma progression and metastasis, and suggest JMJD3 as a potential target for melanoma treatment.

Molecular mechanisms of microRNAs in regulating epithelial-mesenchymal transitions in human cancers

The epithelial-mesenchymal transition (EMT) provides a strong driving force in the progression of various human cancers and the development of chemoresistance. Recently, numbers of studies have demonstrated that microRNAs (miRNAs), by post-transcriptionally silencing EMT-related molecules, can promote or inhibit the EMT process and play pivotal roles in effectively manipulating the occurrence, development, invasion, and metastasis of cancers. MiRNAs can also control the EMT or be controlled by genetic modification and mutual regulation, especially negative feedback. Therefore, miRNAs can be viewed as either oncogenes or tumor suppressor genes to facilitate or retard the EMT, resulting in far-reaching impact on tumor metastasis and effective diagnosis, treatment, and prognosis.

S-adenosylhomocysteine induces inflammation through NFkB: A possible role for EZH2 in endothelial cell activation

S-adenosylhomocysteine (SAH) can induce endothelial dysfunction and activation, contributing to atherogenesis; however, its role in the activation of the inflammatory mediator NFkB has not been explored. Our aim was to determine the role of NFkB in SAH-induced activation of endothelial cells. Furthermore, we examined whether SAH, as a potent inhibitor of S-adenosylmethionine-dependent methyltransferases, suppresses the function of EZH2 methyltransferase to contribute to SAH-induced endothelial cell activation. We found that excess SAH increases the expression of adhesion molecules and cytokines in human coronary artery endothelial cells. Importantly, this up-regulation was suppressed in cells expressing a dominant negative form of the NFkB inhibitor, IkB. Moreover, SAH accumulation triggers the activation of both the canonical and non-canonical NFkB pathways, decreases EZH2, and reduces histone 3 lysine 27 trimethylation. EZH2 knockdown recapitulated the effects of excess SAH on endothelial activation, i.e., it induced NFkB activation and the subsequent up-regulation of adhesion molecules and cytokines. Our findings suggest that suppression of the epigenetic regulator EZH2 by excess SAH may contribute to NFkB activation and the consequent vascular inflammatory response. These studies unveil new targets of SAH regulation, demonstrating that EZH2 suppression and NFkB activation mediated by SAH accumulation may contribute to its adverse effects in the vasculature.

Upregulated expression of miR-106a by DNA hypomethylation plays an oncogenic role in hepatocellular carcinoma

Aberrant microRNA (miRNA) expression has been widely recognized to play an extremely important role in several cancers, including hepatocellular carcinoma (HCC). According to the previous studies, abnormal miR-106a expression was closely related to various cancer occurrences. However, the miR-106a expression in HCC remains unclear. In our study, we firstly detected the miR-106a expression levels in 36 pairs of HCC tissues. The results showed that miR-106a expression in HCC tissues was apparently higher than the level in the adjacent tissues. Then, we used quantitative real-time PCR (qPCR) and BSP to analyze miR-106a expression and promoter methylation in HCC cell lines. There came to a conclusion that the methylation status of the miR-106a promoter region was inversely correlated with the expression of miR-106a. After prediction with online software, we further used dual-luciferase reporter gene assay to ensure that TP53INP1 and CDKN1A might be the direct targets of miR-106a. At last, we explored the functions of miR-106a in HCC cells in vitro. Our results manifested that high-miR-106a cell line had stronger invasiveness, faster cell cycle progression, and more resistance to apoptosis compared with the low-miR-106a cell line. Therefore, our study suggested that upregulated expression of miR-106a by its promoter hypomethylation might contribute to the progression of HCC, which might be considered as a potentially effective biomarker and therapeutic approach in the future.

Differential expression profiling of microRNAs in para-carcinoma, carcinoma and relapse human pancreatic cancer

PURPOSE

To explore the altered different expression of miRNAs and the mechanisms underlying the relapse and metastasis of pancreatic cancer.

MATERIALS AND METHODS

The most differentially expressed miRNAs were analyzed by gene ontology (GO) term analysis, Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis and protein interaction analysis. The potentially regulated target genes of the most differentially expressed miRNAs were also analyzed further by GO term analysis and KEGG pathway analysis, and quantitated by qRT-PCR.

RESULTS

In total, we found 12 miRNAs displayed at least a 30-fold increase or decrease in expression of carcinoma and relapse vs. para-carcinoma human pancreatic cancer (C/R vs. P). In addition, our study found that pancreatic cancer was related to pathways in cancer, including Jak-STAT signaling pathway, MAPK signaling pathway and PPAR signaling pathway.

CONCLUSIONS

The differential expressed miRNAs and their predicted target genes that involved in Jak-STAT signaling pathway, MAPK signaling pathway and PPAR signaling pathway indicating their potential roles in pancreatic carcinogenesis and progress.