MicroRNA-383 regulates the apoptosis of tumor cells through targeting Gadd45g

Horizontal transfer of miR-383 sensitise cells to cisplatin by targeting VEGFA-Akt signalling loop

BACKGROUND

Cellular resistance to cisplatin has been one of the major obstacles in the success of combination therapy for many types of cancers. Emerging evidences suggest that exosomes released by drug resistant tumour cells play significant role in conferring resistance to drug sensitive cells by means of horizontal transfer of genetic materials such as miRNAs. Though exosomal miRNAs have been reported to confer drug resistance, the exact underlying mechanisms are still unclear.

METHODS AND RESULTS

In the present study, mature miRNAs secreted differentially by cisplatin resistant and cisplatin sensitive HepG2 cells were profiled and the effect of most significantly lowered miRNA in conferring cisplatin resistance when horizontally transferred, was analysed. we report miR-383 to be present at the lowest levels among the differentially abundant miRNAs expressed in exosomes secreted by cisplatin resistant cells compared to that that of cisplatin sensitive cells. We therefore, checked the effect of ectopic expression of miR-383 in altering cisplatin sensitivity of Hela cells. Drug sensitivity assay and apoptotic assays revealed that miR-383 could sensitise cells to cisplatin by targeting VEGF and its downstream Akt mediated pathway.

CONCLUSION

Results presented here provide evidence for the important role of miR-383 in regulating cisplatin sensitivity by modulating VEGF signalling loop upon horizontal transfer across different cell types.

Analysis of microRNA expression profiles during the differentiation of chicken embryonic stem cells into male germ cells

The differentiation of embryonic stem cells (ESCs) into germ cells in vitro could have very promising applications for infertility treatment and could provide an excellent model for uncovering the molecular mechanisms of germline generation. This study aimed to investigate the differentially expressed miRNAs (DEMs) during the differentiation of chicken ESCs (cESCs) into male germ cells and to establish a profile of the DEMs. Cells before and after induction were subjected to miRNA sequencing (miRNA-seq). A total of 113 DEMs were obtained, including 61 upregulated and 52 downregulated DEMs. GO and KEGG enrichment analyses showed that the target genes were enriched mainly in the MAPK signaling pathway, HTLV infection signaling pathway, cell adhesion molecule (CAM)-related pathways, viral myocarditis, Wnt signaling pathway, ABC transporters, TGF-β signaling pathways, Notch signaling pathways and insulin signaling pathway. The target genes of the miRNAs were related to cell binding, cell parts and biological regulatory processes. Six DEMs, let-7k-5p, miR-132c-5p, miR-193a-5p, miR-202-5p, miR-383-5p and miR-6553-3p, were assessed by qRT-PCR, and the results were consistent with the results of miRNA-seq. Based on qRT-PCR and western blot verification, miR-383-5p and its putative target gene STRN3 were selected to construct an STRN3 3'-UTR dual-luciferase gene reporter vector and its mutant vector. The double luciferase reporter activity of the cotransfected STRN3-WT + miR-383-5p mimics group was significantly lower (by approximately 46%) than that of the other five groups (p < 0.01). There was no significant difference in luciferase activity among the other 5 groups. This study establishes a DEM profile during the process of cESC differentiation into male germ cells; illustrates the mechanisms by which miRNAs regulate target genes; provides a theoretical basis for further research on the mechanisms of the formation and regulation of male germ cells; and provides an important strategy for gene editing, animal genetic resource protection and transgenic animal production.

Quercetin up-regulates the expression of tumor-suppressive microRNAs in human cervical cancer

Quercetin, a flavonol present in many vegetables and fruits, has been identified as a chemoprevention agent in several cancer models. However, the molecular mechanism of quercetin's anticancer activity is not entirely understood. MicroRNAs (miRNAs), small noncoding RNAs, have been reported to play key roles in various biological processes by regulating their target genes. We hypothesized that quercetin can exert an anticancer effect through the regulation of miRNAs. To test this hypothesis, we investigated the effects of quercetin on the expression of tumor-suppressive miRNAs in cervical cancer. Quercetin up-regulated the in vivo and in vitro expression of tumor-suppressive miRNAs miR-26b, miR-126, and miR-320a. Quercetin suppressed the level of β-catenin, encoded by catenin beta 1 (CTNNB1), by up-regulating miR-320a in HeLa cells. Moreover, quercetin increased the expression of mir-26b, mir-126, and mir-320a precursors in HeLa cells. The results from this study show that quercetin has the potential to prevent cervical cancer by regulating the expression of tumor-suppressive miRNAs.

67-kDa Laminin Receptor-Mediated Cellular Sensing System of Green Tea Polyphenol EGCG and Functional Food Pairing

The body is equipped with a “food factor-sensing system” that senses food factors, such as polyphenols, sulfur-containing compounds, and vitamins, taken into the body, and plays an essential role in manifesting their physiological effects. For example, (–)-epigallocatechin-3-O-gallate (EGCG), the representative catechin in green tea (Camellia sinensi L.), exerts various effects, including anti-cancer, anti-inflammatory, and anti-allergic effects, when sensed by the cell surficial protein 67-kDa laminin receptor (67LR). Here, we focus on three representative effects of EGCG and provide their specific signaling mechanisms, the 67LR-mediated EGCG-sensing systems. Various components present in foods, such as eriodictyol, hesperetin, sulfide, vitamin A, and fatty acids, have been found to act on the food factor-sensing system and affect the functionality of other foods/food factors, such as green tea extract, EGCG, or its O-methylated derivative at different experimental levels, i.e., in vitro, animal models, and/or clinical trials. These phenomena are observed by increasing or decreasing the activity or expression of EGCG-sensing-related molecules. Such functional interaction between food factors is called “functional food pairing”. In this review, we introduce examples of functional food pairings using EGCG.

A Concise Review of MicroRNA-383: Exploring the Insights of Its Function in Tumorigenesis

MicroRNAs (miRNAs) are small noncoding RNAs that commonly have 18-22 nucleotides and play important roles in the regulation of gene expression via directly binding to the 3'-UTR of target mRNAs. Approximately 50% of human genes are regulated by miRNAs and they are involved in many human diseases, including various types of cancers. Recently, microRNA-383 (miR-383) has been identified as being aberrantly expressed in multiple cancers, such as malignant melanoma, colorectal cancer, hepatocellular cancer, and glioma. Increasing evidence suggests that miR-383 participates in tumorigenic events including proliferation, apoptosis, invasion, and metastasis as well as drug resistance. Although downstream targets including CCND1, LDHA, VEGF, and IGF are illustrated to be regulated by miR-383, its roles in carcinogenesis are still ambiguous and the underlying mechanisms are still unclear. Herein, we review the latest studies on miR-383 and summarize its functions in human cancers and other diseases. The goal of this review is to provide new strategies for targeted therapy and further investigations.

MicroRNA-383: A tumor suppressor miRNA in human cancer

Downregulated expression of anti-tumor miR-383 has been found in many kinds of cancer. MiR-383 family members can directly target the 3'-untranslated region (3'-UTR) of the mRNA of some pro-tumor genes to attenuate several cancer-related processes, including cell proliferation, invasion, migration, angiogenesis, immunosuppression, epithelial-mesenchymal transition, glycolysis, chemoresistance, and the development of cancer stem cells, whilst promoting apoptosis. Functionally, miR-383 operates as a tumor inhibitor miRNA in many types of cancer, including breast cancer, hepatocellular carcinoma, gastric cancer, pancreatic cancer, colorectal cancer, esophageal cancer, lung cancer, head and neck cancer, glioma, medulloblastoma, melanoma, prostate cancer, cervical cancer, oral squamous cell carcinoma, thyroid cancer, and B-cell lymphoma. Both pro-tumor and anti-tumor effects have been attributed to miR-383 in ovarian cancer. However, only the pro-tumor effects of miR-383 were reported in cholangiocarcinoma. The restoration of miR-383 expression could be considered a possible treatment for cancer. This review discusses the anti-tumor effects of miR-383 in human cancers, emphasizing their downstream target genes and potential treatment approaches.

[Differences in plasma miRNA levels in inferior petrosal sinus samples of patients with ACTH-dependent Cushing's syndrome]

BACKGROUND

For the last decades microRNAs (miR) have proven themselves as novel biomarkers for various types of diseases. Identification of specific circulating microRNA panel that differ patient with Cushing's disease (CD) and ectopic ACTH syndrome (EAS) could improve the diagnostic procedure.

AIM

to evaluate the differences in miR levels in plasma samples drained from inferior petrosal sinuses in patients with CD and EAS.

MATERIALS AND METHODS

single-center, case-control study: we enrolled 24 patients with ACTH-dependent Cushing's syndrome (CS) requiring bilateral inferior petrosal sinus sampling (BIPSS).  Among them 12 subjects were confirmed as CD (males=2, females=10; median age 46,5 [IR 33,8;53,5]) and 12 as EAS (males=4, females=8, median age 54 [IR 38,75;60,75]). BIPSS was performed through a percutaneous bilateral approach. Once catheters were properly placed, blood samples were withdrawn simultaneously from each petrosal sinus and a peripheral vein. Plasma samples from both sinuses were centrifuged and then stored at -80 C. MiRNA isolation from plasma was carried out by an miRneasy Plasma/Serum Kit (Qiagen, Germany) on the automatic QIAcube station according to the manufacturer protocol. To prevent degradation, we added 1 unit of RiboLock Rnase Inhibitor (Thermo Fisher Scientific, USA) per 1 μL of RNA solution. The concentration of total RNA in the aqueous solution was evaluated on a NanoVue Plus spectrophotometer (GE Healthcare, USA). The libraries were prepared by the QIAseq miRNA Library Kit following the manufacturer standard protocols. MiR expression was then analyzed by sequencing on Illumina NextSeq 500 (Illumina, USA).

RESULTS

108 miRNAs were differently expressed (p &lt;0,05) in inferior petrosal sinus samples of patients with CD vs EAS. We divided these miRNAs into 3 groups based on the significance of the results. The first group consisted of samples with the highest levels of detected miR in both groups. Four miRNAs were included: miR-1203 was downregulated in CD vs EAS - 36.74 (p=0,013), and three other were upregulated in CD vs EAS: miR-383-3p 46.36 (p=0,01), miR-4290 6.84 (p=0,036), miR-6717-5p 4.49 (p=0,031). This miRs will be validated in larger cohorts using RT-qPCR.

CONCLUSION

Plasma miR levels differ in inferior petrosal samples taken from patients with CD vs EAS. These miRs need to be validated by different methods and in peripheral plasma samples in order to be used as potentially non-invasive biomarkers to differentiate ACTH-dependent CS.

The role of tumor suppressor short non-coding RNAs on breast cancer

Characterized by remarkable levels of aggression and malignancy, BC remains one of the leading causes of death in females world wide. Accordingly, significant efforts have been made to develop early diagnostic tools, increase treatment efficacy, and improve patient prognosis. Hopefully, many of the molecular mechanisms underlying BC have been detected and show promising targeting potential. In particular, short and long non-coding RNAs (ncRNAs) are a class of endogenous BC controllers and include a number of different species including microRNAs, Piwi-interacting RNAs, small nucleolar RNA, short interfering RNAs, and tRNA-derivatives. In this review, we discuss the tumor suppressing roles of ncRNAs in the context of BC, and the mechanisms by which ncRNAs target tumor hallmarks, including apoptosis, proliferation, invasion, metastasis, epithelial-mesenchymal transition, angiogenesis, and cell cycle progression, in addition to their diagnostic and prognostic significance in cancer treatment.

MiR-891a-5p as a prognostic marker and therapeutic target for hormone receptor-positive breast cancer

Background: Breast cancer is one of the most frequent malignant tumors worldwide, with 1.67 million newly-diagnosed cases and 522,000 deaths each year. Therefore, seeking the novel biomarkers and therapeutic targets that contribute to postoperative recurrence and metastasis in patients with breast cancer is emerging and facilitates the development of innovative therapeutics. Methods: Retrieving the dataset of patients with hormone receptor (HR)-positive breast cancers from Gene Expression Omnibus (GEO) and collecting the data from the patients with HR-positive breast cancers enrolled in the First Affiliated Hospital of China Medical University are so as to identify the miRNAs associated with metastasis and distant metastasis-free survival (DMFS). Then MTT and Transwell migration assays were used to validate the effect of miRNAs on cell proliferation and migration of estrogen receptor-positive breast cancer T47D and MCF7 cells in vitro, respectively. Results: From GSE59829 dataset, the miRNA expression levels of miR-891a-5p, miR-383-5p and miR-1295a were significantly downregulated while the levels of miR-128-3p, miR-661 and miR-296-3p were significantly upregulated in breast cancers from patients with metastasis as compared to the matched non-metastatic group. Moreover, low expression levels of miR-891a-5p, miR-383-5p and miR-1295a or high expression levels of miR-128-3p, miR-661 and miR-296-3p were respectively associated with low DMFS in patients with breast cancer. Our clinical cohort study supported that the levels of miR-891a-5p, miR-383-5p and miR-1295a were significantly lower in breast cancers from the metastasis group when compared with non-metastatic group. However, there is no significant difference with regard to the levels of miR-128-3p, miR-661 and miR-296-3p in breast cancer between these two groups. Moreover, low expression levels of miR-891a-5p and miR-383-5p but not miR-1295a in breast cancer were significantly associated with low DMFS in patients, implying that the expression of miR-891a-5p and miR-383-5p were the potential prognosis markers for metastatic human breast cancers. Further investigation disclosed that miR-891a-5p but not miR-383-5p restrained both proliferation and migration of T47D and MCF7 cells. In silico analysis of miRNAs target gene through online computational algorithms revealed that A Disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) is the downstream target for miR-891a-5p. Further study confirmed that miR-891a-5p impeded ADAM10 expression by directly binding to its 3'UTR, leading to the inhibition of breast cancer cells proliferation and migration. Moreover, silencing ADAM10 inhibited T47D and MCF7 cells growth and migration. Conclusion: miR-891a-5p is the vital prognostic marker for HR-positive breast cancer. In addition, miR-891a-5p and miR-383-5p are the potential targets for HR-positive breast cancer therapeutics.

Inhibition of miR-383 suppresses oxidative stress and improves endothelial function by increasing sirtuin 1

Previous research has shown that suppression of miR-383 can prevent inflammation of the endothelium, as well as postpone the development of atherosclerosis. However, the role of miR-383 in endothelial cell apoptosis in diabetes remains unclear. The aim of this study was to investigate the function of miR-383 in high glucose-induced apoptosis and oxidative stress in endothelial cells. A series of experiments involving qualitative polymerase chain reaction, cell transfection, luciferase assay, assessment of cell death, detection of catalase and superoxide dismutase concentrations, detection of intracellular reactive oxygen species (ROS), and western blot analysis were performed in this study. We found that miR-383 expression was promoted, while NAD+-dependent deacetylase and sirtuin 1 (SIRT1) expressions were suppressed in the endothelium of the aorta in db/db mice as well as in human umbilical vein endothelial cells, which were treated with high glucose (HG). Increased expression of miR-383 decreased expression of SIRT1, while suppression of miR-383 promoted expression of SIRT1 in human umbilical vein endothelial cells (HUVECs). Furthermore, suppression of miR-383 following transfection with miR-383 suppressor repressed cell death and generation of ROS in HUVECs. SIRT1 knockdown by siRNA-SIRT1 reversed the suppressive effect of miR-383 inhibition on ROS production and cell apoptosis induced by HG treatment. Overall, the findings of our research suggested that suppression of miR-383 repressed oxidative stress and reinforced the activity of endothelial cells by upregulation of SIRT1 in db/db mice, and targeting miR-383 might be promising for effective treatment of diabetes.

Knockdown of PLCB2 expression reduces melanoma cell viability and promotes melanoma cell apoptosis by altering Ras/Raf/MAPK signals

Malignant melanoma has the highest malignancy rate among all skin cancer and is characterized by an insidious onset, high invasion and poor patient prognosis. Yet, the mechanisms involved remain unclear and warrant further investigation. Based on bioinformatic analysis, phospholipase C β2 (PLCB2) has been found to be correlated with melanoma growth. The present study was the first to demonstrate that PLCB2 is a key factor affecting melanoma proliferation and apoptosis. Here, microarray datasets from the publicly available Gene Expression Omnibus (GEO) database were employed, and gene set enrichment analysis (GSEA) was introduced to identify candidate transcription factors. PLCB2 was identified as a crucial gene in the protein‑protein interaction (PPI) network. The expression of PLCB2 mRNA in various cancer lines was analyzed by reverse transcription‑polymerase chain reaction (RT‑PCR). In addition, the proliferation ability and apoptosis rate in human melanoma cells overexpressing or not overexpressing PLCB2 were assessed using colony formation assay, flow cytometry and the Cell Counting Kit‑8 (CCK‑8) assay. Cell viability and apoptosis‑related factors, such as p53, Bcl‑2, Bax and caspase‑3 were significantly regulated. Knockdown of PLCB2 suppressed the activation of the Ras/Raf/MAPK signaling pathway. In conclusion, knockdown of PLCB2 suppressed cell viability and promoted cell apoptosis by activating the Ras/Raf/MAPK pathway. Thus, PLCB2 may utilized as a potential therapeutic target in patients with melanoma.

Inhibition of sirtuin 1 deacetylase by miR-211-5p provides a mechanism for the induction of cell death in breast cancer cells

Sirtuin 1 is one of the regulators of cell growth and survival and its inhibition is suggested as a suitable mechanism to overcome breast cancer development. In this study we explored the role of miR-211-5p in SIRT1/p53 pathway and its influence on breast cancer cell viability and apoptosis. Cells were transfected with miR-211-5p mimic and inhibitor to modulate cellular miR-211-5p levels in breast cancer cell lines, MDA-MB-231 and MCF-7. Gene expression of miR-211-5p and SIRT1 were measured with real-time PCR. SIRT1 protein level and the acetylation of p53 as well as SIRT1 activity were evaluated by Western blotting and fluorometry, respectively. In order to explore the direct attachment of miR-211-5p to the 3'-UTR of SIRT1 mRNA, luciferase reporter assay was applied. Cell viability in response to miR-211-5p was studied by MTT assay and apoptosis was assessed by annexin V labeling followed by flow cytometry. Results showed that SIRT1 gene and protein expression were inhibited by miR-211-5p and the 3'-UTR of SIRT1 was found to be directly targeted by miR-211-5p. Inhibition of SIRT1 expression resulted in its reduced activity. Up-regulation of miR-211-5p was also followed by a significant decline in the acetylation status of p53 which was associated with remarkable decreased cell viability and induction of apoptosis in breast cancer cells. Antisense oligonucleotide of miR-211-5p acted as its inhibitor and exerted opposite effects both on SIRT1 expression and cell apoptosis. In conclusion, inhibition of SIRT1 by miR-211-5p could effectively reduce breast cancer cell survival and cause cell death and therefore might be considered a seemly mechanism for designing anticancer therapies.

Ionizing Radiation-inducible microRNA-21 Induces Angiogenesis by Directly Targeting PTEN

Background:

Previous experimental studies have established that MicroRNAs (miRNAs) can function as oncogenes or tumor suppressors in the regulation of tumor biology or pathology. However, the effects of ionizing radiation (IR) on the expression levels of cellular miRNAs and their further effects on the biological behavior of tumor cells require further investigation.

Methods:

We determined the proliferation, migration and tube formation of HUVEC cells after ionizing radiation (control, 0h and 24h), and the changes of miR-21, VEFG and HIF-1α levels after ionizing radiation were measured by Western blot (WB). The effects of miR-21 mimics and inhibitors on the protein and mRNA expression of PTEN were determined by RT-PCT and WB. Two independent luciferase reporter plasmids were constructed to detect changes in PTEN protein expression.

Results:

We found that both IR and miR-21 increase proliferation, migration and tube formation of HUVEC cells. Ionizing radiation directly targets the inhibition of PTEN expression by causing an increase in miR-21 expression, and induces the accumulation of VEGF and HIF-1α expression in cells by the PI3K / AKT signaling pathway. Simultaneous induction of ectopic expression of PTEN can rescue radiation-induced proliferation, migration and tube formation in tumor cells.

Conclusion:

miR-21 promotes tumor cell proliferation and migration by targeting inhibition of PTEN expression, which may become a potential target for tumor therapy in the future.

Avocado Oil Extract Modulates Auditory Hair Cell Function through the Regulation of Amino Acid Biosynthesis Genes

Sensorineural hearing loss (SNHL) is one of the most common causes of disability, affecting over 466 million people worldwide. However, prevention or therapy of SNHL has not been widely studied. Avocado oil has shown many health benefits but it has not yet been studied in regards to SNHL. Therefore, we aimed to investigate the efficacy of avocado oil on SNHL in vitro and in vivo and elucidate its mode of action. For the present study, we used enhanced functional avocado oil extract (DKB122). DKB122 led to recovery of otic hair cells in zebrafish after neomycin-induced otic cell damage. Also, DKB122 improved auditory sensory transmission function in a mouse model of noise induced-hearing loss and protected sensory hair cells in the cochlea. In addition, RNA sequencing was performed to elucidate the mechanism involved. KEGG pathway enrichment analysis of differentially expressed genes showed that DKB122 protected House Ear Institute-Organ of Corti 1 (HEI-OC1) cells against neomycin-related alterations in gene expression due to oxidative stress, cytokine production and protein synthesis.

miR-383 promotes cholangiocarcinoma cell proliferation, migration, and invasion through targeting IRF1

Interferon regulatory factor 1 (IRF1) has been found to serve as a tumor suppressor in cholangiocarcinoma, and enabled prediction of clinical progression and prognosis in our previous study. The objective of the current study is to screen and identify valuable microRNAs (miR), which target IRF1 to regulate cholangiocarcinoma cell proliferation, migration, and invasion. High expression of miR-383 was observed in cholangiocarcinoma tissues and cells. Meanwhile, we found the predicted binding site of miR-383 on the IRF1 3'-untranslated region (3'-UTR) according to the miR target database. The miR-383 expression was negatively related to IRF1 messeneger RNA (mRNA) and protein expression in cholangiocarcinoma tissue samples, and miR-383 negatively regulated IRF1 mRNA and protein expression in cholangiocarcinoma cells. Subsequently, we conducted a luciferase reporter assay to prove the predicted binding site miR-383 on IRF1 3'-UTR. Moreover, the results of the rescue study suggested that IRF1 was a functional target of miR-383 involved in regulating cholangiocarcinoma cell proliferation, migration, and invasion. Finally, we evaluated the clinical and prognostic significance of miR-383 in cholangiocarcinoma cases, and found that high expression of miR-383 was correlated with advanced tumor stage, large tumor size, present vascular invasion, and metastasis, and acted as an unfavorable independent prognostic factor. In conclusion, miR-383 serves as a tumor-suppressive miR to regulate cholangiocarcinoma cell proliferation, migration, and invasion via directly targeting IRF1.

MicroRNA-383 upregulation protects against propofol-induced hippocampal neuron apoptosis and cognitive impairment

Anesthesia-induced cognitive impairment is a recognized clinical phenomenon. The present study aimed to investigate the effect of microRNA-383 (miR-383) expression on propofol-induced learning and memory impairment. In total, 48 male Sprague-Dawley rats (weight, 250±10 g) were randomly divided into four groups (n=12 each): Control group, and three groups of rats that were anesthetized with propofol for 6 h and untreated (propofol model group), treated with a constructed lentivirus vector expressing miR-383 mimics (mimic + propofol group), or treated with miR-383 scramble (scramble + propofol group). The learning memory ability, hippocampal neuron apoptosis and expression of apoptosis-associated factors were detected using reverse transcription-quantitiative polymerase chain reaction and western blot analysis. Propofol treatment significantly reduced the relative mRNA and protein expression of miR-383, induced neuron apoptosis, upregulated the Bax/Bcl-2 ratio, downregulated the relative mRNA and protein expression levels of postsynaptic density protein 95 and cAMP-response element binding protein, and inactivated the phosphoinositide 3-kinase/protein kinase B signaling pathway. By contrast, miR-383 mimics significantly altered the propofol-induced dysregulation of the aforementioned factors. In conclusion, miR-383 mimic was able to repair propofol-induced cognitive impairment via protecting against hippocampal neuron apoptosis and dysregulation of related factors. The present study suggested that miR-383 may be used as a potential therapeutic target for the clinical treatment of cognitive impairment induced by propofol anesthesia.

Upregulation of microRNA-383 inhibits the proliferation, migration and invasion of colon cancer cells

Increasing evidence demonstrates that microRNAs (miRNAs/miRs), a type of non-coding small RNA, can regulate tumor cell migration, invasion and metastasis, and may therefore serve a major function in the occurrence and development of tumors. The present study investigated the effect of miR-383 on the proliferation, migration and invasion of colon cancer HT-29 and LoVo cell lines. The expression of miR-383 in colon cancer and adjacent non-tumor tissues was examined by reverse transcription-quantitative polymerase chain reaction. MiR-383 upregulation was stimulated by transfection with a miR-383 mimic. Cell proliferation was measured with MTT and colony formation assays, and cell migration and invasion potential were examined by Transwell chamber assays. A proliferating-inducing ligand (APRIL), myeloid cell leukemia-1 and cyclooxygenase-2 protein expression was analyzed by western blotting. The expression of miR-383 was decreased in colon cancer tissues compared with adjacent non-tumor tissues (P<0.05). Transfection with a miR-383 mimic suppressed proliferation and inhibited cell migration and invasion in HT-29 and LoVo colon cancer cell lines. Overexpression of miR-383 in HT-29 and LoVo cells resulted in the suppression of APRIL protein expression. In conclusion, miR-383 was downregulated in colon cancer. The upregulation of miR-383 inhibited proliferation, migration and invasion of colon cancer cells, potentially through the regulation of target gene APRIL.

GSK-J4-Mediated Transcriptomic Alterations in Differentiating Embryoid Bodies

Histone-modifying enzymes are key players in the field of cellular differentiation. Here, we used GSK-J4 to profile important target genes that are responsible for neural differentiation. Embryoid bodies were treated with retinoic acid (10 μM) to induce neural differentiation in the presence or absence of GSK-J4. To profile GSKJ4-target genes, we performed RNA sequencing for both normal and demethylase-inhibited cells. A total of 47 and 58 genes were up- and down-regulated, respectively, after GSK-J4 exposure at a log2-fold-change cut-off value of 1.2 (p-value < 0.05). Functional annotations of all of the differentially expressed genes revealed that a significant number of genes were associated with the suppression of cellular proliferation, cell cycle progression and induction of cell death. We also identified an enrichment of potent motifs in selected genes that were differentially expressed. Additionally, we listed upstream transcriptional regulators of all of the differentially expressed genes. Our data indicate that GSK-J4 affects cellular biology by inhibiting cellular proliferation through cell cycle suppression and induction of cell death. These findings will expand the current understanding of the biology of histone-modifying enzymes, thereby promoting further investigations to elucidate the underlying mechanisms.

A novel epigenetic AML1-ETO/THAP10/miR-383 mini-circuitry contributes to t(8;21) leukaemogenesis

DNA methylation patterns are frequently deregulated in t(8;21) acute myeloid leukaemia (AML), but little is known of the mechanisms by which specific gene sets become aberrantly methylated. Here, we found that the promoter DNA methylation signature of t(8;21)+ AML blasts differs from that of t(8;21)- AMLs. This study demonstrated that a novel hypermethylated zinc finger-containing protein, THAP10, is a target gene and can be epigenetically suppressed by AML1-ETO at the transcriptional level in t(8;21) AML. Our findings also show that THAP10 is a bona fide target of miR-383 that can be epigenetically activated by the AML1-ETO recruiting co-activator p300. In this study, we demonstrated that epigenetic suppression of THAP10 is the mechanistic link between AML1-ETO fusion proteins and tyrosine kinase cascades. In addition, we showed that THAP10 is a nuclear protein that inhibits myeloid proliferation and promotes differentiation both in vitro and in vivo Altogether, our results revealed an unexpected and important epigenetic mini-circuit of AML1-ETO/THAP10/miR-383 in t(8;21) AML, in which epigenetic suppression of THAP10 predicts a poor clinical outcome and represents a novel therapeutic target.

microRNA-383 mediates high glucose-induced oxidative stress and apoptosis in retinal pigment epithelial cells by repressing peroxiredoxin 3

Hyperglycemia-mediated damage to retinal pigment epithelial (RPE) cells plays a central role in the pathogenesis of diabetic retinopathy. Dysregulation of microRNA (miR)-383 modulates pancreatic beta cell survival in diabetes; however, its role in diabetic retinopathy remains unclear. In this study, we examined the expression of miR-383 in ARPE-19 human RPE cell lines after high glucose treatment and investigated its functions in high glucose-induced reactive oxygen species (ROS) generation and apoptotic responses. The downstream target gene that mediated the action of miR-383 was functionally characterized. It was found that high glucose induced a 2.4-fold increase in miR-383 abundance, compared to ARPE-19 cells treated with normal glucose. Overexpression of miR-383 inhibited cell viability and promoted apoptosis and ROS formation in ARPE-19 cells, which was coupled with deregulation of Bcl-2 and Bax. Peroxiredoxin 3 (PRDX3) expression was repressed by miR-383 in ARPE-19 cells. Restoration of PRDX3 counteracted miR-383-induced ROS generation and apoptosis, while silencing of PRDX3 phenocopied the detrimental effects of miR-383 on ARPE-19 cells. Delivery of anti-miR-383 inhibitors led to an increase of PRDX3 expression and prevented high glucose-elicited ROS formation and apoptosis in ARPE-19 cells. Overall, miR-383 upregulation accounts for high glucose-induced oxidative stress and apoptosis in RPE cells by repressing PRDX3 expression. Targeting miR-383 may have therapeutic potential in the treatment of diabetic retinopathy.

EPO-cyclosporine combination therapy reduced brain infarct area in rat after acute ischemic stroke: role of innate immune-inflammatory response, micro-RNAs and MAPK family signaling pathway

This study tested the hypothesis that erythropoietin (EPO) and cyclosporine (CsA) could effectively reduce brain infarct area (BIA) in rat after acute ischemic stroke (AIS) through regulating inflammation, oxidative stress, MAPK family signaling and microRNA (miR-223/miR-30a/miR-383). Adult male Sprague-Dawley rats (n = 48) were equally divided into group 1 (sham control), group 2 (AIS), group 3 [AIS+EPO (5,000 IU/kg at 0.5/24/48 h, subcutaneous)] and group 4 [AIS+CsA (20.0 mg/kg at 0.5/24/48 h, intra-peritoneal)]. By 72 h, histopathology showed that BIA was largest in group 2 and smallest in group 1, and significantly larger in group 4 than group 3 (all P<0.0001). The three microRNAs expressed were higher in group 2 than in the other three groups (all P<0.04); between these three latter groups there were no significant differences. The protein expressions of MAPK family [phosphorylated (p)-ERK1/2, p-p38/p-JNK], inflammatory (iNOS/MMP-9/TNF-α/NF-κB/IL-12/MIP-1α/CD14/CD68/Ly6g), apoptotic (caspase-3/PARP/mitochondrial-Bax), oxidative-stress (NOX-1/NOX-2/oxidized protein) and mitochondrial-damaged (cytosolic cytochrome-C) biomarkers exhibited an identical pattern to BIA findings (all P<0.0001). The cellular expressions of brain edema (AQP4+), inflammation (CD11+/glial-fibrillary-acid protein+), and cellular damage (TUNEL assay/positive Periodic acid-Schiff stain) biomarkers exhibited an identical pattern, whereas the cellular-integrity markers (neuN+/MAP2+/doublecorin+) exhibited an opposite pattern to BIA (all P value <0.001). EPO-CsA therapy markedly reduced BIA mainly by suppressing the innate immune response to inflammation, oxidative stress, microRNAs (miR-223/miR-30a/miR-383) and MAPK family signaling.

Neuroprotective effect of miR-665 against sevoflurane anesthesia-induced cognitive dysfunction in rats through PI3K/Akt signaling pathway by targeting insulin-like growth factor 2

The aim of this study was to investigate the in vivo and in vitro effects of miR-665 on sevoflurane anesthesia-induced cognitive dysfunction. SH-SY5Y cells and male SD rats were treated with sevoflurane to simulate anesthesia-induced cognitive dysfunction. The cells and rats both were transfected with a miR-665 mimic, inhibitor, scramble, IGF-2 siRNA, or treated with P13K/Akt inhibitor LY294002. The cell apoptosis, autophagy, growth related proteins, and mRNA levels were measured using different methods. The motor performance was assessed using the Morris water maze (MWM) test. Finally, the differences were statistically analyzed. It was noted that sevoflurane-induced miR-665 downregulation accompanied with the upregulation of IGF-2 in vivo and motor deficits in vitro. Moreover, sevoflurane also induced hippocampal neuroapoptosis; reduced regular autophagy; increased Bax/Bcl-2 ratio; decreased the expression of Beclin 1, PSD95, and p-CREB; and activated P13K/Akt signaling pathway. However, the treatment by miR-665 mimics significantly reversed all the molecular changes and improved motor performance. Our data demonstrate the neuroprotective effect of miR-665 against sevoflurane anesthesia-induced cognitive impairment. This study suggests that miR-665 might be explored as a potential target of therapy for sevoflurane-induced cognitive impairment.

The Value of MiR-383, an Intronic MiRNA, as a Diagnostic and Prognostic Biomarker in Intestinal-Type Gastric Cancer

MicroRNAs, a class of gene expression regulatory non-coding RNAs, participate in the pathogenic mechanisms of gastric cancer which is one of the life-treating cancers. Due to its aberrant expression in some types of human cancer, miR-383 has the value of being investigated in relation to cancer treatment and diagnosis. MiR-383 is placed in intron of SGCZ, a protein-coding gene, which is subject to dysregulation in various diseases. The purpose of the current study was to investigate the contribution of miR-383 to intestinal-type gastric adenocarcinoma tumorigenesis. The expression level of miR-383 was investigated by qRT-PCR in pairs of tumorous and adjacent tumor-free tissues of 40 patients with gastric cancer during endoscopy. Also, the susceptibility of miR-383 as a tumor marker and the relationship between its aberrant expression and clinicopathological features were determined. qRT-PCR data showed that miR-383 was dysregulated during gastric tumorigenesis. MiR-383 was dramatically downregulated up to sevenfold in intestinal-type gastric adenocarcinoma compared with adjacent tumor-free tissues (P < 0.001). Misregulation of miR-383 did not reveal a significant correlation with clinical characteristics. The ROC area of 80% with 76% sensitivity and 84% specificity was determined by P < 0.001. The current study demonstrated downregulation of miR-383 in intestinal-type gastric adenocarcinoma. Downregulation of miR-383 might be used as a potential tumor marker for the diagnosis of gastric cancer or could be a potential target for gene therapy.

MicroRNA-383 located in frequently deleted chromosomal locus 8p22 regulates CD44 in prostate cancer

A major genomic alteration in prostate cancer (PCa) is frequent loss of chromosome (chr) 8p with a common region of loss of heterozygosity (LOH) at chr8p22 locus. Genomic studies implicate this locus in the initiation of clinically significant PCa and with progression to metastatic disease. However, the genes within this region have not been fully characterized to date. Here we demonstrate for the first time that a microRNA component of this region –miR-383- is frequently downregulated in prostate cancer, plays a critical role in determining tumor initiating potential and is involved in prostate cancer metastasis via direct regulation of CD44, a ubiquitous marker of PCa tumor initiating cells (TICs)/ stem cells. Expression analyses of miR-383 in PCa clinical tissues established that low miR-383 expression is associated with poor prognosis. Functional data suggests that miR-383 regulates PCa tumor initiating/ stem-like cells via CD44 regulation. Ectopic expression of miR-383 inhibited tumor initiating capacity of CD44+ PCa cells. Also, ‘anti-metastatic’ effects of ectopic miR-383 expression were observed in a PCa experimental metastasis model. In view of our results, we propose that frequent loss of miR-383 at chr8p22 region leads to tumor initiation and prostate cancer metastasis. Thus, we have identified a novel finding that associates a long observed genomic alteration to PCa stemness and metastasis. Our data suggests that restoration of miR-383 expression may be an effective therapeutic modality against PCa. Importantly, we identified miR-383 as a novel PCa tissue diagnostic biomarker with a potential that outperforms that of serum PSA.

Epigallocatechin-3-O-gallate up-regulates microRNA-let-7b expression by activating 67-kDa laminin receptor signaling in melanoma cells

MicroRNAs (miRNAs) are non-coding RNAs involved in various biological processes by regulating their target genes. Green tea polyphenol (−)-epigallocatechin-3-O-gallate (EGCG) inhibits melanoma tumor growth by activating 67-kDa laminin receptor (67LR) signaling. To examine the effect of EGCG on miRNA expression in melanoma cells, we performed miRNA microarray analysis. We showed that EGCG up-regulated miRNA-let-7b expression through 67LR in melanoma cells. The EGCG-induced up-regulation of let-7b led to down-regulation of high mobility group A2 (HMGA2), a target gene related to tumor progression. 67LR-dependent cAMP/protein kinase A (PKA)/protein phosphatase 2A (PP2A) signaling pathway activation was involved in the up-regulation of let-7b expression induced by EGCG. These findings provide a basis for understanding the mechanism of miRNA regulation by EGCG.

The Role of MicroRNAs in the Chemoresistance of Breast Cancer

Preclinical Research Breast cancer is the most prevalent malignancy in women with more than 1.3 million new cases every year worldwide. Chemotherapy is a critical therapeutic strategy for breast cancer, while chemoresistance remains a major obstacle to treatment success. In the past two decades, significant progress has been achieved in understanding drug resistance in breast cancer, involving drug efflux, alterations in DNA repair pathways, suppression of apoptosis as well as epithelial-mesenchymal transition, and cancer stem cells. However, more effective therapeutic targets and novel biomarkers are still urgently needed to improve the overall survival and refine the therapeutic strategy for breast cancer patients. MicroRNAs (miRNAs) play crucial roles in cellular processes, such as cell differentiation, proliferation, and apoptosis. The recent discovery of miRNAs in malignancy has provided new directions for research on mechanisms underlying response to chemotherapy. Furthermore, several studies have documented that selected miRNAs, such as miR-200c and miR-34a, may influence response to chemotherapy in several tumor types, including breast cancer. The use of miRNAs as therapeutic targets to overcome chemoresistance is currently under investigation. In this review, we summarize the roles of miRNAs in chemoresistance through multiple molecular mechanisms, and highlight the potential diagnostic and therapeutic applications of miRNAs in overcoming breast cancer chemoresistance.

MicroRNAs Used in Combination with Anti-Cancer Treatments Can Enhance Therapy Efficacy

MicroRNAs (miRNAs), a recently discovered class of small non-coding RNAs, constitute a promising approach to anti-cancer treatments when they are used in combination with other agents. MiRNAs are evolutionarily conserved non-coding RNAs that negatively regulate gene expression by binding to the complementary sequence in the 3'-untranslated region (UTR) of target genes. MiRNAs typically suppress gene expression by direct association with target transcripts, thus decreasing the expression levels of target proteins. The delivery to cells of synthetic miRNAs that mimic endogenous miRNA targeting genes involved in the DNA-Damage Response (DDR) can perturb the process, making cells more sensitive to chemotherapy or radiotherapy. This review examines how cells respond to combined therapy and it provides insights into the role of miRNAs in targeting the DDR repair pathway when they are used in combination with chemical compounds or ionizing radiation to enhance cellular sensitivity to treatments.