miRNA423-5p regulates cell proliferation and invasion by targeting trefoil factor 1 in gastric cancer cells

Ame-miR-1-3p of bee venom reduced cell viability through the AZIN1/OAZ1-ODC1-polyamines pathway and enhanced the defense ability of honeybee (Apis mellifera L.)

Bee venom serves as an essential defensive weapon for bees and also finds application as a medicinal drug. MicroRNAs (miRNAs) serve as critical regulators and have been demonstrated to perform a variety of biological functions. However, the presence of miRNAs in bee venom needs to be confirmed. Therefore, we conducted small RNA sequencing and identified 158 known miRNAs, 15 conserved miRNAs and 4 novel miRNAs. It is noteworthy that ame-miR-1-3p, the most abundant among them, accounted for over a quarter of all miRNA reads. To validate the function of ame-miR-1-3p, we screened 28 candidate target genes using transcriptome sequencing and three target gene prediction software (miRanda, PITA and TargetScan) for ame-miR-1-3p. Subsequently, we employed real-time quantitative reverse transcription PCR (qRT-PCR), Western blot and other technologies to confirm that ame-miR-1-3p inhibits the relative expression of antizyme inhibitor 1 (AZIN1) by targeting the 3' untranslated region (UTR) of AZIN1. This, in turn, caused ODC antizyme 1 (OAZ1) to bind to ornithine decarboxylase 1 (ODC1) and mark ODC1 for proteolytic destruction. The reduction in functional ODC1 ultimately resulted in a decrease in polyamine biosynthesis. Furthermore, we determined that ame-miR-1-3p accelerates cell death through the AZIN1/OAZ1-ODC1-polyamines pathway. Our studies demonstrate that ame-miR-1-3p diminishes cell viability and it may collaborate with sPLA2 to enhance the defence capabilities of honeybees (Apis mellifera L.). Collectively, these data further elucidate the defence mechanism of bee venom and expand the potential applications of bee venom in medical treatment.

Identification of Neck Lymph Node Metastasis-Specific microRNA-Implication for Use in Monitoring or Prediction of Neck Lymph Node Metastasis

MicroRNAs (miRNAs) have attracted attention as non-invasive cancer biomarkers in various cancers; however, they have not been adequately investigated in oral squamous cell carcinoma (OSCC). This study investigated the diagnostic performance of serum-derived miRNAs at initial diagnosis for primary neck lymph node metastasis and the predictive performance for late neck lymph node metastasis based on long-term (up to approximately 8 years) follow-up of patients with OSCC. The expression of miRNAs in 40 patients with OSCC was quantified using real-time PCR (qPCR), and a comprehensive statistical analysis of the correlation of miRNA expression for primary and late neck lymph node metastases was performed. For the diagnosis of primary neck lymph node metastases, miR-423 and miR-125 were accurate. The miRNA index for primary metastasis diagnosis (miR-PM) calculated by regression analysis showed high diagnostic accuracy. The miR-5100 was useful for predicting late neck lymph node metastases. The miRNA index for late metastasis prediction (miR-LM) calculated using regression analysis showed high prediction accuracy. MiRNAs were useful for diagnosing primary neck lymph node metastases in OSCC and predicting late neck lymph node metastases. It may help to consider individualized treatment, including follow-up, surgical methods, and postoperative management.

MiR-423-5p is a novel endogenous control for the quantification of circulating miRNAs in human esophageal squamous cell carcinoma

Circulating miRNA expression is most commonly measured by qRT-PCR, however, the lack of a suitable endogenous control hinders people from evaluating the accurate changes in miRNA expression levels and developing the non-invasive biomarkers. In this study, we aimed to screen the specific, highly stable endogenous control in esophageal squamous cell carcinoma (ESCC) to overcome the obstacle. We selected "housekeeping" miRNAs according to the published database and initially acquired 21 miRNAs. Subsequently, we screened these miRNAs using GSE106817 and TCGA datasets according to specific inclusion criteria and evaluated the suitability of "candidate" miRNAs. Among these miRNAs, the average abundance of miR-423-5p was relatively high in serum. Notably, miR-423-5p expression in serum showed no significant difference between ESCC patients and healthy controls (n = 188, P = 0.29). Moreover, among these miRNAs, miR-423-5p was the most stable miRNA using the NormFinder algorithms. Overall, these results indicate that miR-423-5p, as a novel and optimal endogenous control, could be used to quantify circulating miRNAs in ESCC.

A Proteomic Approach Reveals That miR-423-5p Modulates Glucidic and Amino Acid Metabolism in Prostate Cancer Cells

Recently, we have demonstrated that miR-423-5p modulates the growth and metastases of prostate cancer (PCa) cells both in vitro and in vivo. Here, we have studied the effects of miR-423-5p on the proteomic profile in order to identify its intracellular targets and the affected pathways. Applying a quantitative proteomic approach, we analyzed the effects on the protein expression profile of miR-423-5p-transduced PCa cells. Moreover, a computational analysis of predicted targets of miR-423-5p was carried out by using several target prediction tools. Proteomic analysis showed that 63 proteins were differentially expressed in miR-423-5-p-transfected LNCaP cells if compared to controls. Pathway enrichment analysis revealed that stable overexpression of miR-423-5p in LNCaP PCa cells induced inhibition of glycolysis and the metabolism of several amino acids and a parallel downregulation of proteins involved in transcription and hypoxia, the immune response through Th17-derived cytokines, inflammation via amphorin signaling, and ion transport. Moreover, upregulated proteins were related to the S phase of cell cycle, chromatin modifications, apoptosis, blood coagulation, and calcium transport. We identified seven proteins commonly represented in miR-423-5p targets and differentially expressed proteins (DEPs) and analyzed their expression and influence on the survival of PCa patients from publicly accessible datasets. Overall, our findings suggest that miR-423-5p induces alterations in glucose and amino acid metabolism in PCa cells paralleled by modulation of several tumor-associated processes.

CircRNA PVT1 modulated cell migration and invasion through Epithelial-Mesenchymal Transition (EMT) mediation in gastric cancer through miR-423-5p/Smad3 pathway

Background

Gastric cancer (GC) progression is related with gene regulations.

Objectives

This study explored underlying regulatory axis of circRNA PVT1 (circPVT1) in GC.

Methods

GC cell lines were detected for circPVT1 expression with the normal mucous epithelial cell GES-1 as control. After regulation of circPVT1, miR-423-5p and SMAD3 expression through transfection, CCK8 evaluated the cell viability, Transwell measured the migratory and invasive capability of cells. Luciferase verified the paired bindings between miR-423-5p and CircPVT1 or SMAD3. The functions of CircPVT1/miR-423-5p/SMAD3 were evaluated using RT-PCR, CCK8, Transwell assays. Western blot analyzed EMT-related proteins and phosphorylation of Smad3 in GC cells. Immunofluorescence method was used to evaluate the EMT-related proteins as well.

Results

CircPVT1 displayed higher expression in GC cells and knockdown led to decrease in cell growth, invasion and migration. CircPVT1 was targeted by miR-423-5p as a ceRNA of SMAD3. miR-423-5p upregulation suppressed both cicRNA PVT1 and SMAD3 in GC cells. Decrease in SMAD3 expression suppressed CircPVT1 by releasing miR-423-5p in cells, inhibiting cell growth, invasion and migration and suppressing the EMT process.

Conclusion

CircPVT1 modulated cell growth, invasion and migration through EMT mediation in gastric cancer through miR-423-5p/Smad3 pathway.

The miR-3648/FRAT1-FRAT2/c-Myc negative feedback loop modulates the metastasis and invasion of gastric cancer cells

Although the abnormal expression of miRNAs in cancer cells is a widely accepted phenomenon, the molecular mechanisms underlying miR-3648 progression and metastasis in gastric cancer (GC) remain unclear. miR-3648 expression is downregulated and its ectopic expression in GC cells significantly suppressed cell proliferation and metastasis. Mechanistic analyses indicated that miR-3648 directly targets FRAT1 or FRAT2 and inhibits FRAT1- or FRAT2-mediated invasion and motility in vitro and in vivo. Moreover, FRAT1 physically interacted with FRAT2. Furthermore, FRAT1 overexpression promoted GC cell invasion, whereas siRNA-mediated repression of FRAT2 in FRAT1-overexpressing GC cells reversed its invasive potential. Besides, miR-3648 inactivated the Wnt/β-catenin signalling pathway by downregulating FRAT1 and FRAT2 in GC. Interestingly, c-Myc, a downstream effector of Wnt/β-catenin signalling, was also downregulated by miR-3648 overexpression. In turn, c-Myc negatively regulated miR-3648 expression by binding to the miR-3648 promoter. In addition, miR-3648 expression levels were negatively correlated with c-Myc, FRAT1, and FRAT2 expression in fresh gastric samples. Our studies suggest that miR-3648 acts as a tumour-suppressive miRNA and that the miR-3648/FRAT1-FRAT2/c-Myc negative feedback loop could be a critical regulator of GC progression.

Investigating melanogenesis-related microRNAs as disease biomarkers in vitiligo

Vitiligo is considered a disabling disease that affects physical, social, psychological, and occupational aspects of an individual's quality of life. The search for non-invasive and reliable biomarkers for vitiligo's early diagnosis, prognosis, and treatment prediction is under intensive investigation. There is currently an emerging interest in employing miRNAs as biomarkers to predict vitiligo diagnosis and prognosis, inspired by the well-preserved nature of miRNAs in serum or plasma. In the current study, we assessed a panel of 20 melanogenesis pathway-related microRNAs (miRNAs) using quantitative real-time PCR technique in 85 non-segmental vitiligo (NSV) patients compared to 85 normal controls followed by function and pathway enrichment analysis for the miRNAs with significant results. Twelve out of the 20 circulating miRNAs showed significantly higher expression levels in vitiligo patients relative to controls where miR-423 show the highest expression level followed by miR-182, miR-106a, miR-23b, miR-9, miR-124, miR-130a, miR-203a, miR-181, miR-152, and miR-320a. While six miRNAs (miR-224, miR-148a, miR-137, and miR-7, miR-148b, miR-145, miR-374b, and miR-196b) didn’t show significant expression level. The analysis of the receiver operating curve indicated that miR-423, miR-106a, and miR-182 were outstanding biomarkers with the highest areas under the curve in vitiligo. This study is the first Egyptian study to investigate a panel of miRNAs expression profile in the plasma of patients with NSV. Our results suggest that specific circulating miRNAs signature might be implicated in vitiligo pathogenesis and could potentially be used as biomarkers in vitiligo.

Hsa_circ_0000081 promotes the function of gastric cancer through sponging hsa-miR-423-5p to influence 3-phosphoinositide-dependent kinase 1 expression

Gastric cancer (GC) is one of the most common malignancies in the world, and effective therapeutic targets need to be identified for this type of cancer. In this study, circular RNA (circRNA) microarray analysis was utilized to screen differentially expressed circRNA in GC. Using quantitative reverse transcription polymerase chain reaction (qRT-PCR), hsa_circ_0000081 (circRNA-0000081) expression was found to be up-regulated in tissues and cells and was negative correlated with patients' survival time. RNase R and Actinomycin D assays indicated that circRNA-0000081 was significantly more resistant to R enzyme and had a longer half-life than linear RNA. Moreover, the knockdown or overexpression of circRNA-000081 could influence the proliferation, migration, and invasion potential of GC. Finally, dual luciferase reporter, RNA immunoprecipitation, qRT-PCR, and western blotting assays were used to verify the targeting relationship between circRNA-000081 and miRNA-423-5p or miRNA-423-5p and 3-phosphoinositide-dependent kinase 1 (PDPK1). In conclusion, circRNA-0000081 promotes the function of GC through sponging hsa-miR-423-5p to influence PDPK1 expression, which has a promising therapeutic potential for treating patients with GC.

Up-regulation of long noncoding RNA MBNL1-AS1 suppresses breast cancer progression by modulating miR-423-5p/CREBZF axis

Breast cancer is the leading cause of cancer-related death among females, which is required to be solved urgently. Recent studies have found significant changes in a large number of genes and their transcriptional levels during breast cancer development, which are often closely related to the abnormal expression of long noncoding RNAs (lncRNAs). Herein, our study found that MBNL1-AS1 was down-regulated both in breast cancer tissues and cell lines, and it functioned as a tumor suppressor to inhibit cancer cell proliferation, migration, and invasion. MiR-423-5p was found to be a target of MBNL1-AS1 with an inverse relationship: an increase in miR-423-5p could counteract the inhibitory effect induced by MBNL1-AS1 on cancer cell promotion. Further, CREBZF was negatively regulated by miR-423-5p. Accordingly, CREBZF knockdown could impair the hindrance of cancer cell growth mediated by low miR-423-5p expression. Also, MBNL1-AS1 influenced the PI3K/AKT pathway, which was associated with cell proliferation and apoptosis, by regulating CREBZF. As a result, our work illustrated the tumor suppressor role of MBNL1-AS1 in breast cancer via upregulating miR-423-5p-targeted CREBZF. Thereby, the evidence indicates the complete understanding of the role of MBNL1-AS1/miR-423-5p/CREBZF axis in the regulation of breast cancer development, which could be used as a biomarker for predicating survival among breast cancer patients.

Genetic Variation in MicroRNA-423 Promotes Proliferation, Migration, Invasion, and Chemoresistance in Breast Cancer Cells

MicroRNA-423 (miR-423) is highly expressed in breast cancer (BC). Previously, our group showed that the SNP rs6505162:C>A located in the pre-miR-423 was significantly associated with increased familial BC risk in patients with a strong family history of BC. Therefore, in this study, we evaluated the functional role of rs6505162 in mammary tumorigenesis in vitro to corroborate the association of this SNP with BC risk. We found that rs6505162:C>A upregulated expression of both mature miR-423 sequences (3p and 5p). Moreover, pre-miR-423-A enhanced proliferation, and promoted cisplatin resistance in BC cell lines. We also showed that pre-miR-423-A expression decreased cisplatin-induced apoptosis, and increased BC cell migration and invasion. We propose that the rs6505162-A allele promotes miR-423 overexpression, and that the rs6505162-A allele induces BC cell proliferation, viability, chemoresistance, migration, and invasion, and decreases cell apoptosis as a consequence. We suggest that rs6505162:C>A is a functional SNP site with potential utility as a marker for early diagnosis, prognosis, and treatment efficacy monitoring in BRCA1/2-negative BC patients, as well as a possible therapeutic target.

Insulin promotes hepatocarcinoma tumorigenesis by up-regulating PKM2 expression

Insulin, as a growth factor, can increase the risk of certain types of cancer. The present study showed that insulin promoted the proliferation of hepatocellular carcinoma cells in vitro and in vivo through pyruvate kinase M2 (PKM2), which is a rate-limiting enzyme in the process of glycolysis. Moreover, the expression of PKM2 was up-regulated by insulin at the posttranslational level in a nuclear orphan receptor TR3-dependent manner. In addition, insulin could enhance the interaction between PKM2 and TR3 and protect PKM2 from degradation. Our results identified a specific mechanism of insulin affecting cancer metabolism and thus promoting cancer progression, and they contribute to a better understanding of the observation that insulin is linked to an increased cancer risk under hyperinsulinemic conditions.

Cancer driver gene and non-coding RNA alterations as biomarkers of brain metastasis in lung cancer: A review of the literature

Brain metastasis (BM) is the most common event in patients with lung cancer. Despite multimodal treatments and advances in systemic therapies, development of BM remains one of the main factors associated with poor prognosis and mortality in patients with lung cancer. Therefore, better understanding of mechanisms involved in lung cancer brain metastasis (LCBM) is of great importance to suppress cancer cells and to improve the overall survival of patients. Several cancer-related genes such as EGFR and KRAS have been proposed as potential predictors of LCBM. In addition, there is ample evidence supporting crucial roles of non-coding RNAs (ncRNAs) in mediating LCBM. In this review, we provide comprehensive information on risk assessment, predictive, and prognostic panels for early detection of BM in patients with lung cancer. Moreover, we present an overview of LCBM molecular mechanisms, cancer driver genes, and ncRNAs which may predict the risk of BM in lung cancer patients. Recent clinical studies have focused on determining mechanisms involved in LCBM and their association with diagnosis, prognosis, and treatment outcomes. These studies have shown that alterations in EGFR, KRAS, BRAF, and ALK, as the most frequent coding gene alterations, and dysregulation of ncRNAs such as miR-423, miR-330-3p, miR-145, piR-651, and MALAT1 can be considered as potential biomarkers of LCBM.

TFF-1 Functions to Suppress Multiple Phenotypes Associated with Lung Cancer Progression

Introduction

Trefoil Factor (TFF) is a member of a protein family comprised of three isoforms, of which TFF-1 exhibits antithetical functions; promotion or suppression of cell proliferation, survival and invasion, depending on the cancer type. However, the pathobiological function of TFF-1 in lung carcinoma has been still unclear.

Methods

We examined the expression and secretion of TFF-1 using cultured human lung carcinoma cells by immunoblotting, immunofluorescence, enzyme-linked immunosorbent assay and quantitative real-time PCR analyses. The effects of TFF-1 on various phenotypes were analyzed in two cell lines, including those transfected with cDNA encoding TFF-1. Cell proliferation and death were examined by hemocytometer cell counting and by colorimetric viability/cytotoxicity assay. Cell cycle profile, migration and invasion were also examined by flow cytometry, wound healing assay and Matrigel Transwell assay, respectively. The effect of TFF-1 overexpression was confirmed by additional transfection of TFF-1-specific siRNA.

Results

Endogenous TFF-1 protein expression and secretion into the media were observed exclusively in adenocarcinoma-derived cell lines. Forced overexpression of TFF-1 drove cell cycle transition, while the proliferation decreased by 19% to 25% due to increased cell death. This cell death was predominantly caused by apoptosis, as assessed by the activation of caspase 3/7. Cell migration was also suppressed by 71% to 82% in TFF-1-transfected cells. The suppressive effect of TFF-1 on proliferation and migration was restored by transfection of TFF-1 siRNA. Moreover, invasion was also suppressed to 77% to 83% in TFF-1-transfected cells.

Conclusion

These findings reveal that TFF-1 functions as a suppressor of cancer proliferation by induction of apoptosis, cell migration and invasion and thus may provide a synergistic target for potential treatment strategies for human lung carcinoma.

Role of Exosomal Non-coding RNAs in Gastric Cancer: Biological Functions and Potential Clinical Applications

Gastric cancer (GC) is one of the most common fatal cancers worldwide. The communication between GC and other cells in the GC microenvironment directly affects GC progression. Recently, exosomes have been revealed as new players in intercellular communication. They play an important role in human health and diseases, including cancer, owing to their ability to carry various bioactive molecules, including non-coding RNAs (ncRNAs). NcRNAs, including micro RNAs, long non-coding RNAs, and circular RNAs, play a significant role in various pathophysiological processes, especially cancer. Increasing evidence has shown that exosomal ncRNAs are involved in the regulation of tumor proliferation, invasion, metastasis, angiogenesis, immune regulation, and treatment resistance in GC. In addition, exosomal ncRNAs have promising potential as diagnostic and prognostic markers for GC. Considering the biocompatibility of exosomes, they can also be used as biological carriers for targeted therapy. This review summarizes the current research progress on exosomal ncRNAs in gastric cancer, focusing on their biological role in GC and their potential as new biomarkers for GC and therapeutics. Our review provides insight into the mechanisms involved in GC progression, which may provide a new point cut for the discovery of new diagnostic markers and therapeutic strategies.

Polymorphisms in genes involved in breast cancer among Iranian patients

This review gives a summary of the important genetic polymorphisms in breast cancer with a focus on people in Iran. Several single nucleotide polymorphisms were considered as breast cancer susceptibility polymorphisms within genes (STK15, ERRs, ESR1, p53, SEP15, AURKA, SHBG, SRC, FAS, VEGF, XRCC1, GST, NFκB1, XPC, XRCC3, sirtuin-3, NKG2D). Cytosine-adenine repeat (IGF-I), rs3877899, G-2548A, GGC (eRF3a/GSPT1), IVS2nt-124A/G have shown an increased risk of breast cancers and a decreased risk has been observed in 4G/5G (PAI-1), rs6505162, tri-nucleotide (GCG TGFBR1). We observed that the signaling pathways and antioxidant related genes are the main molecular processes associated with breast cancer progression. Further studies on types of polymorphisms in breast cancer could validate the prognostic value of biomarkers.

Functional mechanism and clinical implications of MicroRNA-423 in human cancers

MicroRNAs play a vital role in the regulatory mechanisms of tumorigenesis. Current research indicates that microRNA-423 (miR-423) is abnormally expressed in various human tumors and participates in multiple signaling pathways of cancer progression. In most studies, miR-423 was confirmed as oncomiR, while a few contradictory reports considered miR-423 as an anticancer miRNA. The paradoxical role in cancer may hinder the application of miR-423 as a diagnostic and therapeutic target. Simultaneously, the interaction mechanism between miR-423 and lncRNA also needs attention. In this review, we have summarized the dual role of aberrant miR-423 expression and its mechanisms in tumorigenesis, and the therapeutic potential of miR-423 in human tumors.

Total triterpenoids from the fruits of Chaenomeles speciosa exerted gastroprotective activities on indomethacin-induced gastric damage via modulating microRNA-423-5p-mediated TFF/NAG-1 and apoptotic pathways

Our previous studies have demonstrated that the total triterpenes from the fruits of Chaenomeles speciosa (CSTT) exhibit effective therapeutic effects on gastric ulcer patients and animals. The present aim is to further investigate the mechanisms involved. The results indicated that CSTT could ameliorate IND-induced gastric injury, which was related to promoting IND-damaged GES-1 cell proliferation and migration, improving the IND-damaged rat GBF, ulcer area, inhibition rate and pathologic changes of gastric mucous tissue, increasing the amount of adhered gastric mucus, attenuating the volume and total acidity of the gastric effluents, and augmenting the gastric pH; further studies showed that CSTT obviously downregulated miR-423-5p mRNA, NAG-1 mRNA and protein expression, Bax, Bad, cytosol cytochrome C, Apaf-1, cleaved-caspase-3, and cleaved-caspase-9 protein expression and cytosol cytochrome C concentration, and upregulated TFF1, TFF2 and TFF3 mRNA and protein expression, Bcl-2, Bcl-xl, pro-caspase-3, and pro-caspase-9 protein expression, mitochondrial viability, mitochondrial cytochrome C concentration and Bcl-2/Bax, Bcl-xl/Bad ratios. These findings demonstrated that CSTT protected against IND-induced gastric damage by depressing miR-423-5p expression and modulating the TFF/NAG-1 pathway, which in turn restrained mitochondrion-mediated apoptosis.

The lncRNA XIST promotes proliferation, migration and invasion of gastric cancer cells by targeting miR-337

BACKGROUND AND STUDY AIMS

Gastric cancer (GC) is one of the most common malignant tumours worldwide. Long non-coding RNAs (lncRNAs) and microRNAs regulate the occurrence and development of various cancers and play an important role in GC progression. X-inactive specific transcript (XIST), a carcinogenic lncRNA, is involved in human tumourigenesis and is altered in GC. Janus kinase 2 (JAK2), a transcription factor, is involved in cancer cell metastasis and differentiation. However, the exact mechanism underlying the biological roles of XIST and JAK2 in cancer cells remains unclear.

MATERIAL AND METHODS

This study was conducted using GES-1, HGC-27, AGS and HEK-293 T cells. Quantitative polymerase chain reaction and western blotting were performed to detect XIST, microRNA-337 (miR-337) and JAK2 expressions. GC cell invasion was investigated by using the Transwell assay. Fluorescein reporter gene detection was used to determine the relationship between JAK2 and XIST.

RESULTS

Compared with that in GES-1 cells, XIST expression was significantly up-regulated in AGS and HGC-27 cells. miR-337 expression in GC cell lines was decreased. The proliferation, invasion and migration of GC cells were simultaneously inhibited by XIST knockdown, and the relationship between XIST and miR-337 was confirmed by bioinformatics analysis. JAK2 is expected to be the target gene of miR-337. MiR-337 can negatively regulate JAK2 expression in vitro. In addition, si-XIST decreased JAK2 expression by up-regulating miR-337 in vitro, thereby inhibiting GC cell proliferation and migration. Therefore, we speculated that XIST regulates JAK2 by competing with miR-337 as a competitive endogenous lncRNA in GC.

CONCLUSION

We elucidated the effects of migration and invasion after XIST inhibition, at least in part, by inhibiting miR-337 expression in GC cells to regulate JAK2. These data indicate that a positive feedback loop exists between XIST and JAK2 and suggest that JAK2 and XIST play a vital role in cancer cell migration and invasion.

LINC01426 contributes to clear cell renal cell carcinoma progression by modulating CTBP1/miR-423-5p/FOXM1 axis via interacting with IGF2BP1

Increasing evidence suggests that long noncoding RNAs (lncRNAs) are pivotal regulators in oncogenesis. However, the role of numerous lncRNAs has never been unmasked in clear cell renal cell carcinoma (ccRCC). Presently, we investigated the function of long intergenic nonprotein coding RNA 1426 (LINC01426) in ccRCC, as The Cancer Genome Atlas data indicated that LINC01426 was highly expressed in ccRCC tissues and its overexpression was correlated with disappointing prognosis. First, we verified that LINC01426 was indeed upregulated in ccRCC cell lines and its depletion restrained ccRCC cell proliferation and migration. Besides, we proved that LINC01426 facilitated ccRCC tumorigenesis via forkhead box M1 (FOXM1). Moreover, it was revealed that miR-423-5p was downregulated and directly targeted FOXM1 in ccRCC, and that LINC01426 positively regulated FOXM1 via its inhibition on miR-423-5p. Notably, we also uncovered that miR-423-5p was transcriptionally silenced by CTBP1 and HDAC2. Of importance, LINC01426 was certified to distribute both in the cytoplasm and the nucleus of ccRCC cells, and it increased CTBP1 expression through recruiting insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) in cytoplasm whereas interacted with CTBP1 protein to improve the transcriptional repression on miR-423-5p in nucleus. Jointly, our observations unveiled that LINC01426 aggravates ccRCC progression via IGF2BP1/CTBP1/HDAC2/miR-423-5p/FOXM1 axis, highlighting LINC01426 as a novel promising target for ccRCC treatment.

Odyssey of trefoil factors in cancer: Diagnostic and therapeutic implications

Trefoil factors 1, 2, and 3 (TFFs) are a family of small secretory molecules involved in the protection and repair of the gastrointestinal tract (GI). TFFs maintain and restore epithelial structural integrity via transducing key signaling pathways for epithelial cell migration, proliferation, and invasion. In recent years, TFFs have emerged as key players in the pathogenesis of multiple diseases, especially cancer. Initially recognized as tumor suppressors, emerging evidence demonstrates their key role in tumor progression and metastasis, extending their actions beyond protection. However, to date, a comprehensive understanding of TFFs' mechanism of action in tumor initiation, progression and metastasis remains obscure. The present review discusses the structural, functional and mechanistic implications of all three TFF family members in tumor progression and metastasis. Also, we have garnered information from studies on their structure and expression status in different organs, along with lessons from their specific knockout in mouse models. In addition, we highlight the emerging potential of using TFFs as a biomarker to stratify tumors for better therapeutic intervention.

MiR-423-5p may regulate ovarian response to ovulation induction via CSF1

BACKGROUND

We have previously shown that hsa-miR-423-5p expression in ovarian granulosa cells is decreased in high ovarian response populations. The objective of the present study was to find the target gene and mechanism for miR-423-5p involved in ovarian response regulation.

METHODS

(a) TargetScan was used to predict the target gene of hsa-miR-423-5p. (b) A model for hsa-miR-423-5p overexpression or inhibition was constructed by transfecting KGN cells with lentivirus. CSF1 mRNA and protein expression and luciferase activity were measured. (c) The cell cycles of control and lentivirus treated KGN cells were analyzed. Western blot was used to measure the expression of CDKN1A in KGN cells. (d) The concentration of E₂ in KGN cell culture medium were measured.

RESULTS

(a) TargetScan revealed that the 3' un-translated region of CSF1 matched 11 bases at the 5' end of miR-423-5p, making it a likely target gene. (b) Overexpression or inhibition of miR-423-5p were associated with respective decreases or increases in CSF1 expression (both mRNA and protein) (p < 0.05) and luciferase activity (p < 0.05). (c) When miR-423-5p expression increased, the number of G0/G1 phase cells and the expression of CDKN1A protein increased while estradiol concentrations in the cell culture solution decreased (p < 0.05). However, when miR-423-5p expression decreased, the number of S phase cells increased and E2 concentrations increased while the expression of CDKN1A protein decreased (p < 0.05).

CONCLUSIONS

Colony stimulating factor 1 is a target gene of miR-423-5p and that it may regulate ovarian response to ovulation induction by affecting granulosa cells proliferation and estrogen secretion.

MUC1 is associated with TFF2 methylation in gastric cancer

Background

Emerging evidence has shown that MUC1 and TFF2 play crucial roles in the H. pylori-infected pathogenesis of gastric cancer (GC). A recent study revealed that H. pylori infection induced obviously increased Tff2 methylation levels in Muc1^−/− mice compared with controls. However, little is known of the molecular mechanism on MUC1 regulating the expression of TFF2.

Methods

We conducted a correlation analysis of MUC1 and TFF2 in public databases and our adjacent GC tissues. Besides, MUC1 overexpression vector or small interfering RNA (siRNA) was transfected into GC cells to assess the change in TFF2 expression. Furthermore, the methylation status of TFF2 was measured by bisulfite sequencing PCR (BSP).

Results

The expression of MUC1 was significantly lower in non-cardia and cardia tumor tissues than that in normal tissues. Downregulation of TFF2 expression was also observed in GC tissues. In addition, we found that MUC1 expression was positively associated with TFF2 expression in GC tissues, especially among GC patients with H. pylori infection. Overexpression of MUC1 in BGC-823 and SGC-7901 cell lines substantially increased the TFF2 expression, whereas knockdown of MUC1 reverted this effect. Moreover, MUC1 was negatively related to the methylation of TFF2 in the co-expression analysis. The results of BSP experiments showed that compared with negative vector group, the methylation level of TFF2 was decreased in GC cells transfected with MUC1 overexpression vector. Additionally, survival analysis indicated that GC patients with lower level of MUC1 or TFF2 had a worse outcome.

Conclusion

Our results indicated that MUC1 was associated with the methylation of TFF2, which may have implications for TFF2 expression in GC. These findings warrant further research toward the underlying mechanism of MUC1 influenced the TFF2 methylation.

An integrated analysis of the circRNA-miRNA-mRNA network reveals novel insights into potential mechanisms of cell proliferation during liver regeneration

Cell proliferation constitutes the fundamental process and driving force behind regrowth during liver regeneration (LR). However, it remains unclear how competing endogenous RNA (ceRNA) networks affect hepatocyte proliferation and liver regeneration. Therefore, this study was designed to explore an LR-specific ceRNA network, which regulates cell proliferation. Based on the microarray data of mRNAs, and high-throughput sequencing data of miRNAs and circRNAs from regenerating livers, this study initially applied known 1484 LR associated mRNAs to perform GO analysis, and then selected 169 LR associated mRNAs involved in cell proliferation and the cell cycle. Subsequently, 188 interactive miRNA-mRNA pairs and 5206 circRNA-miRNA pairs, respectively, were predicted using bioinformatics methods. Next, in view of the differential expressions of these ceRNAs during LR, 26 miRNA-mRNA pairs and 71 circRNA-miRNA pairs were applied to generate a circRNA-miRNA-mRNA regulatory network, and only 14 triple interactive groups were obtained based on the predicted inverse interactions among ceRNAs. Finally, circ_19698/miR-423-5p axis was demonstrated to promote cell proliferation by modulating the expression of MYC, CCNA2, and CCND1 in rat BRL-3A cells. This study suggests a potential regulatory mechanism of cell proliferation in regenerating livers, as well as a novel pathway for modulating ceRNA networks to promote liver regeneration.

MicroRNA-423 Drug Resistance and Proliferation of Breast Cancer Cells by Targeting ZFP36

BACKGROUND/AIMS

The effects of microRNA-423 on proliferation and drug resistance of breast cancer cells were explored, the downstream target genes of miR-423 and the targeted regulatory relationship between them were studied.

METHODS

RT-qPCR was used to detect the expression of miR-423 in breast cancer tissues and cell lines, and the transfection efficiency of miR-423 inhibitory vector miR-423-inhibitor was constructed and verified. CCK-8 and colony formation assays were used to examine the effect of miR-423 on tumor cell proliferation. Target gene prediction and screening and luciferase reporter assay were used to verify downstream target genes of miR-432. The mRNA and protein expression of miR-423target gene ZFP36 was detected by RT-qPCR and Western blotting.

RESULTS

The expression of miR-423 was significantly higher than that in normal tissues. Compared to the non-malignant mammary epithelial cell line MCF-10A, the expression of miR-423 was significantly raised in MCR-7 and MCF-7/ADR cells. ZFP36 was a downstream target gene of miR-423 and negatively correlated with the expression of miR-423 in breast cancer. The knockdown of miR-423 can significantly enhance the cytotoxicity of the drug, increase the apoptotic rate of MCF-7/ADR cells. miR-423 was capable of activating the Wnt/β-catenin signaling pathway leading to chemoresistance and proliferation, whereas overexpression of ZFP36 reduced drug resistance and proliferation.

CONCLUSION

miR-423 acted as an oncogene to promote tumor cell proliferation and migration. ZFP36 was a downstream target gene of miR-423, and miR-423 inhibited the expression of ZFP36 via Wnt/β-catenin signaling pathway of breast cancer cells.

miR-9-5p Suppresses Malignant Biological Behaviors of Human Gastric Cancer Cells by Negative Regulation of TNFAIP8L3

BACKGROUND

MicroRNA is essential for the malignant progression of human gastric cancer (GC), which is a leading cause of cancer deaths. However, the mechanism is still not so clear.

AIMS

In our present research, we investigated the effect of miR-9-5p in GC.

METHODS

We detected miR-9-5p expression in human gastric epithelial cell (GES-1) and GC cells (AGS, BGC-823, MKN-45, and MGC-803), plasma of normal or GC patients, as well as orthotopic xenograft mouse models by real-time PCR. The migration ability was detected by Transwell assays after miR-9-5p mimic or inhibitor transfection in GC cells.

RESULTS

Our results showed that miR-9-5p expression in GC cells and plasma was significantly decreased. miR-9-5p inhibited migration of GC cells by regulating TNFAIP8L3 directly. Low expression of miR-9-5p in GC patients hardly suppressed the migration mediated by TNFAIP8L3.

CONCLUSIONS

miR-9-5p, as a potential tumor suppressor gene, is closely related to the malignant progression of GC. Exploring the regulation between miR-9-5p and TNFAIP8L3 may provide a novel strategy for GC treatment.

NFE2/miR-423-5p/TFF1 axis regulates high glucose-induced apoptosis in retinal pigment epithelial cells

Background

A study has shown that miR-423-5p is highly expressed in proliferative diabetic retinopathy. However, the exact biological functions and mechanisms of miR-423-5p in diabetic retinopathy (DR) progression are currently unclear. This study aimed to investigate the role of miR-423-5p in DR and the underlying mechanism.

Results

Our data demonstrate that the expression of miR-423-5p is significantly increased in HG-induced RPE cells and DR patient plasma. Moreover, the overexpression of miR-423-5p exacerbates HG-induced apoptosis. Mechanistically, our results provide evidence that miR-423-5p directly targets TFF1. MiR-423-5p exerts its effect on HG-induced apoptosis in RPE cells through TFF1, and the NF-κB pathway is involved in the regulatory mechanism. Further analysis revealed that the transcription factor NFE2 regulates miR-423-5p promoter activity. In addition, NFE2 regulates the levels of TFF1 and NF-κB pathway-associated proteins by regulating the expression of miR-423-5p.

Conclusion

The NFE2-miR-423-5p-TFF1 axis is a novel molecular mechanism and provides a new direction for the study and treatment of DR.

Comparative Identification of MicroRNAs in Apis cerana cerana Workers' Midguts in Responseto Nosema ceranae Invasion

Here, the expression profiles and differentially expressed miRNAs (DEmiRNAs) in the midguts of Apis cerana cerana workers at 7 d and 10 d post-inoculation (dpi) with N. ceranae were investigated via small RNA sequencing and bioinformatics. Five hundred and twenty nine (529) known miRNAs and 25 novel miRNAs were identified in this study, and the expression of 16 predicted miRNAs was confirmed by Stem-loop RT-PCR. A total of 14 DEmiRNAs were detected in the midgut at 7 dpi, including eight up-regulated and six down-regulated miRNAs, while 12 DEmiRNAs were observed in the midgut at 10 dpi, including nine up-regulated and three down-regulated ones. Additionally, five DEmiRNAs were shared, while nine and seven DEmiRNAs were specifically expressed in midguts at 7 dpi and 10 dpi. Gene ontology analysis suggested some DEmiRNAs and corresponding target mRNAs were involved in various functions including immune system processes and response to stimulus. KEGG pathway analysis shed light on the potential functions of some DEmiRNAs in regulating target mRNAs engaged in material and energy metabolisms, cellular immunity and the humoral immune system. Further investigation demonstrated a complex regulation network between DEmiRNAs and their target mRNAs, with miR-598-y, miR-252-y, miR-92-x and miR-3654-y at the center. Our results can facilitate future exploration of the regulatory roles of miRNAs in host responses to N. ceranae, and provide potential candidates for further investigation of the molecular mechanisms underlying eastern honeybee-microsporidian interactions.

Long non-coding RNA LINC00968 reduces cell proliferation and migration and angiogenesis in breast cancer through up-regulation of PROX1 by reducing hsa-miR-423-5p

Background: Breast cancer (BC) is a common invasive malignancy in women with unclear etiology. A recent study suggested that long non-coding RNA (lncRNA), LINC00968 had a tumor-promoting effect in cancer. However, the role of LINC00968 in BC remains unclear. Therefore, we conducted the present study to determine the effect of LINC00968 in BC and its underlying mechanism. Methods: The expression of LINC00968 and hsa-miR-423-5p in BC tissues and cells was determined using reverse transcription quantitative polymerase chain reaction and western blot analysis. Dual luciferase reporter, RNA pull-down and RNA immunoprecipitation assays were used to determine the relationship among LINC00968, PROX1 and hsa-miR-423-5p. Gain- and loss-function approaches were utilized to examine the effects of LINC00968, PROX1 and hsa-miR-423-5p on cell proliferation, migration, tube formation in vitro; and tumor growth and angiogenesis in vivo. Results: LINC00968 expression reduced while hsa-miR-423-5p increased in BC tissues relative to adjacent normal tissues. Overexpression of LINC00968 was observed to inhibit BC cell proliferation, migration and tube formation abilities in vitro as well as tumor growth in vivo through inhibition of hsa-miR-423-5p. And hsa-miR-423-5p mediated BC cellular functions and tumor growth through down-regulating PROX1. LINC00968 was identified as a competing endogenous RNA to upregulate PROX1 by downregulating hsa-miR-423-5p. More importantly, it was found that LINC00968 increased PROX1 expression in vivo in a concentration-dependent manner. Conclusion: Taken together, this study suggests that LINC00968 inhibits the progression of BC through impeding hsa-miR-423-5p-mediated PROX1 inhibition. LINC00968 may be a potential therapeutic target for BC therapy that warrants further studies.

MicroRNAs contribute to ATP-binding cassette transporter- and autophagy-mediated chemoresistance in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has an elevated mortality rate, largely because of high recurrence and metastasis. Additionally, the main obstacle during treatment of HCC is that patients usually develop resistance to chemotherapy. Cancer drug resistance involves many different mechanisms, including alterations in drug metabolism and processing, impairment of the apoptotic machine, activation of cell survival signaling, decreased drug sensitivity and autophagy, among others. Nowadays, miRNAs are emerging as master regulators of normal physiology- and tumor-related gene expression. In HCC, aberrant expression of many miRNAs leads to chemoresistance. Herein, we particularly analyzed miRNA impact on HCC resistance to drug therapy. Certain miRNAs target ABC (ATP-binding cassette) transporter genes. As most of these miRNAs are downregulated in HCC, transporter levels increase and intracellular drug accumulation decrease, turning cells less sensitive to death. Others miRNAs target autophagy-related gene expression, inhibiting autophagy and acting as tumor suppressors. Nevertheless, due to its downregulation in HCC, these miRNAs do not inhibit autophagy or tumor growth and, resistance is favored. Concluding, modulation of ABC transporter and/or autophagy-related gene expression or function by miRNAs could be determinant for HCC cell survival under chemotherapeutic drug treatment. Undoubtedly, more insights on the biological processes, signaling pathways and/or molecular mechanisms regulated by miRNAs are needed. Anyway, miRNA-based therapy together with conventional chemotherapeutic drugs has a great future in cancer therapy.

An overview of the multifaceted roles of miRNAs in gastric cancer: Spotlight on novel biomarkers and therapeutic targets

MicroRNAs (miRNAs) are a group of small non-coding RNAs that have displayed strong association with gastric cancer (GC). Through the repression of target mRNAs, miRNAs regulate many biological pathways that are involved in cell proliferation, apoptosis, migration, invasion, metastasis as well as drug resistance. The detection of miRNAs in tissues and in body fluids emerges as a promising method in the diagnosis and prognosis of GC, due to their unique expression pattern in correlation with GC. Notably, miRNAs are also identified as potential therapeutic targets for GC therapy. The present review is thus to highlight the multifaceted roles of miRNAs in GC and in GC therapies, which would give indications for future research.

miR-632 promotes gastric cancer progression by accelerating angiogenesis in a TFF1-dependent manner

Background

Gastric cancer (GC) is a common malignant disease worldwide. Aberrant miRNAs expression contributes to malignant cells behaviour, and in preclinical research, miRNA targeting has shown potential for improving GC therapy. Our present study demonstrated that miR-632 promotes GC progression in a trefoil factor 1 (TFF1)-dependent manner.

Methods

We collected GC tissues and serum samples to detect miR-632 expression using real-time PCR. A dual-luciferase reporter assay was used to identify whether miR-632 directly regulates TFF1 expression. Tube formation and endothelial cell recruitment assays were performed with or without miR-632 treatment. Western blot and in situ hybridization assays were performed to detect angiogenesis and endothelial recruitment markers that are affected by miR-632.

Results

Our results showed that miR-632 is highly expressed in GC tissue and serum and negatively associated with TFF1 in GC. miR-632 improves tube formation and endothelial cell recruitment by negatively regulating TFF1 in GC cells. Recombinant TFF1 reversed miR-632-mediated angiogenesis. TFF1 is a target gene of miR-632.

Conclusions

Our study demonstrated that miR-632 promotes GC progression by accelerating angiogenesis in a TFF1-dependent manner. Targeting of miR-632 may be a potential therapeutic approach for GC patients.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5247-z) contains supplementary material, which is available to authorized users.

miR-150-5p promotes the proliferation and epithelial-mesenchymal transition of cervical carcinoma cells via targeting SRCIN1

Cervical carcinoma is one of the most universal cancers among women. Recent researches have reported that microRNA-150-5p (miR-150-5p) is up-regulated in diverse carcinomas containing cervical carcinoma. The purpose of this study was to further investigate the potential role of miR-150-5p in the progress of cervical carcinoma cells including proliferation and epithelial-mesenchymal transition (EMT).The ability of miR-150-5p to promote carcinogenesis was analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot assays, respectively. Bioinformatics analyses predicted and identified whether SRC kinase signaling inhibitor 1 (SRCIN1) was served as a potential target of miR-150-5p. C-33A and HeLa cells were utilized to determine the function of miR-150-5p through targeting SRCIN1. Among the aberrantly expressed miRNAs, miR-150-5p was significantly revealed differential expression in cervical carcinoma cell lines and was closely relevant to cell growth regulation. Furthermore, we found that SRCIN1 overexpression could obviously inhibit the proliferation and EMT of cervical cancer cells triggered by miR-150-5p mimics as well as accelerated the apoptosis of cervical carcinoma cells. In conclusion, our data demonstrated that miR-150-5p could promote the proliferation and EMT of cervical carcinoma cells via targeting SRCIN1. Thus, miR-150-5p may hold a promise as a prognostic biomarker and potential therapeutic target for cervical carcinoma.

LncRNA LINC00319 accelerates ovarian cancer progression through miR-423-5p/NACC1 pathway

Long noncoding RNA (lncRNA) LINC00319 has been reported to promote carcinogenesis of lung cancer and cutaneous squamous cell carcinoma. However, the role and mechanism of LINC00319 in ovarian cancer progression is unclear. In this study, LINC00319 expression was found to be upregulated in ovarian cancer tissues and cell lines. And our evidence showed that LINC00319 could be a potential prognostic biomarker for patients with ovarian cancer. Cell Counting Kit-8 (CCK-8), colony formation and transwell assays indicated that LINC00319 upregulation promoted proliferation, migration and invasion of ovarian cancer cells. Bioinformatics analysis and luciferase reporter assay revealed that LINC00319 worked as the sponge for miR-423-5p. Furthermore, miR-423-5p directly targeted NACC1. qRT-PCR and western blot results demonstrated that LINC00319 upregulates NACC1 expression through inhibiting miR-423-5p in ovarian cancer cells. Moreover, we observed an inverse expression correlation between miR-423-5p and LINC00319 or between miR-423-5p and NACC1 in ovarian cancer tissues. Finally, rescue assay showed that NACC1 restoration rescued the potentials of proliferation, migration and invasion in LINC00319-depleted ovarian cancer cells. In conclusion, our findings demonstrated that LINC00319 promotes ovarian cancer progression through upregulating NACC1 expression by restraining miR-423-5p.

MicroRNA-423-5p inhibits the progression of trophoblast cells via targeting IGF2BP1

INTRODUCTION

Preeclampsia (PE) is one of the leading causes of maternal and fetal mortality globally. The imbalance of trophoblast homeostasis is closely linked with the pathogenesis of PE. MicroRNA-423-5p (miR-423-5p) has been reported to be abnormally expressed in placenta and blood plasma of pregnant women with PE. In the present study, miR-423-5p expression in blood plasma of pregnant women with PE and healthy pregnant women was detected. Also, the roles and molecular mechanisms of miR-423-5p in the development of trophoblast cells were further investigated.

METHODS

Expression of miR-423-5p and insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) mRNA was detected by RT-qPCR assay. Protein expression of IGF2BP1, Bcl-2 and Bax was determined using western blot assay. Cell migratory and invasive capacities were assessed by transwell migration and invasion assay. Cell apoptotic rate was determined using flow cytometry via the double-staining of Annexin V-FITC/Propidium Iodide. The interaction between miR-423-5p and IGF2BP1 was demonstrated by bioinformatics analysis and luciferase reporter assay.

RESULTS

MiR-423-5p was highly expressed in blood plasma of pregnant women with PE. MiR-423-5p inhibited migration, invasion and proliferation as well as induced apoptosis in HTR-8/SVneo cells. Further investigation revealed that IGF2BP1 was a target of miR-423-5p. Moreover, IGF2BP1 overexpression promoted migration, invasion and proliferation, suppressed apoptosis, and weakened miR-423-5p function in HTR-8/SVneo cells.

DISCUSSION

MiR-423-5p inhibited migration, invasion and proliferation as well as induced apoptosis by targeting IGF2BP1 in HTR-8/SVneo cells, presenting a novel molecular basis implicated in PE pathogenesis.

Inhibition of miR-423-5p suppressed prostate cancer through targeting GRIM-19

OBJECTIVE

To determine the effect of miR-423-5p on the progression of prostate cancer (PC).

METHODS

miR-423-5p and GRIM-19 expressions were detected by qRT-PCR and western blot. PC cell proliferation was measured by MTT assay. PC cell apoptosis was detected by flow cytometry. Dual luciferase reporter assay was used to confirm the interaction between miR-423-5p and GRIM-19.

RESULTS

Compared with normal prostate tissues and prostate epithelial cell HPrEC, miR-423-5p was up-regulated in human PC tissues and PC3 cells, whereas GRIM-19 expression was decreased. Inhibition of miR-423-5p suppressed PC3 cell proliferation, promoted PC3 cell apoptosis, and decreased anti-apoptosis protein BCL-2 expression. GRIM-19 was a target of miR-423-5p, and GRIM-19 was negatively regulated by miR-423-5p in PC3 cells. In addition, miR-423-5p knockdown inhibited the proliferation and promoted the apoptosis of PC3 cells through GRIM-19. In vivo experiments showed that miR-423-5p inhibitor administration reduced tumor volume, down-regulated miR-423-5p and GRIM-19 expressions in PC tissues of nude mice.

CONCLUSION

Inhibition of miR-423-5p suppressed PC through targeting GRIM-19.

Long noncoding RNA AFAP1-AS1 acts as a competing endogenous RNA of miR-423-5p to facilitate nasopharyngeal carcinoma metastasis through regulating the Rho/Rac pathway

BACKGROUND

Actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), a long noncoding RNA, is significantly highly expressed and associated with metastasis and poor prognosis in many cancers, including nasopharyngeal carcinoma (NPC). In this study, we aim to identify the role of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC metastasis.

METHODS

The role of AFAP1-AS1, miR-423-5p, and FOSL2 in NPC metastasis was investigated in vitro and in vivo. Bioinformatics analysis and luciferase activity assays were used to identify the interaction between AFAP1-AS1, miR-423-5p, and FOSL2. Additionally, real-time PCR and western blotting were used to assess the function of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC progression by regulating miR-423-5p and the downstream Rho/Rac pathway.

RESULTS

In this study, we determined that AFAP1-AS1 functions as a competing endogenous RNA in NPC to regulate the Rho/Rac pathway through miR-423-5p. These interactions can mediate the expression of RAB11B, LASP1, and FOSL2 and accelerate cell migration and invasion via the Rho/Rac signaling pathway or FOSL2. AFAP1-AS1 and FOSL2 could competitively bind with miR-423-5p to regulate several molecules, including RAB11B and LASP1 of the Rho/Rac signaling pathway. AFAP1-AS1 can also regulate the expression of LASP1, which was transcriptionally regulated by FOSL2, resulting in increased migration and invasion of NPC cells via the Rho/Rac signaling pathway.

CONCLUSIONS

The observations in this study identify an important role for AFAP1-AS1 as a competing endogenous RNA (ceRNA) in NPC pathogenesis and indicate that it may serve as a potential target for cancer diagnosis and treatment.

Involving the microRNA Targetome in Esophageal-Cancer Development and Behavior

Esophageal cancer (EC) is the eighth most common and sixth leading cause of cancer-related mortality in the world. Despite breakthroughs in EC diagnosis and treatment, patients with complete pathologic response after being submitted to chemoradiotherapy are still submitted to surgery, despite its high morbidity. Single-nucleotide polymorphisms (SNPs) in miRNA, miRNA-binding sites, and in its biogenesis pathway genes can alter miRNA expression patterns, thereby influencing cancer risk and prognosis. In this review, we systematized the information available regarding the impact of these miR-SNPs in EC development and prognosis. We found 34 miR-SNPs that were associated with EC risk. Despite the promising applicability of these miR-SNPs as disease biomarkers, they still lack validation in non-Asian populations. Moreover, there should be more pathway-based approaches to evaluate the cumulative effect of multiple unfavorable genotypes and, consequently, identify miR-SNPs signatures capable of predicting EC therapy response and prognosis.

Exosomal miR-423-5p targets SUFU to promote cancer growth and metastasis and serves as a novel marker for gastric cancer

Exosomes are critically involved in tumor growth, metastasis, and therapy resistance. Exosomes have the potential to be utilized as cancer biomarkers. In this study, we aimed to explore the roles and clinical values of exosomal miRNAs in gastric cancer. We found that the concentration of exosomes was significantly higher in the serum of gastric cancer patients and the culture supernatants of gastric cancer cells than that in healthy volunteers and gastric mucosa epithelial cells. In particular, miR-423-5p was elevated in the serum exosomes of gastric cancer patients, and the level of exosomal miR-423-5p was remarkably correlated with lymph node metastasis. High level of exosomal miR-423-5p was associated with poor outcome in gastric cancer patients. MiR-423-5p enriched exosomes could be internalized into gastric cancer cells, which enhanced cell proliferation and migration both in vitro and in vivo. Mechanistically, miR-423-5p inhibited the expression of suppressor of fused protein (SUFU) to enhance the proliferation and migration of gastric cancer cells. The expression levels of SUFU were significantly decreased in gastric cancer cells and the tumor tissues of gastric cancer patients. Taken together, our findings indicate that exosomes could deliver miR-423-5p to promote cancer growth and metastasis and serum exosomal miR-423-5p may serve as a potential marker for gastric cancer diagnosis and prognosis.

Exosomal miRNAs species in the blood of small cell and non-small cell lung cancer patients

Lung cancer is a devastating disease with overall bleak prognosis. Current methods to diagnose lung cancer are rather invasive and are inadequate to detect the disease at an early stage when treatment is likely to be most effective. In this study, a shotgun sequencing approach was used to study the microRNA (miRNA) cargo of serum-derived exosomes of small cell lung cancer (SCLC) (n=9) and non-small cell lung cancer (NSCLC) (n=11) patients, and healthy controls (n=10). The study has identified 17 miRNA species that are differentially expressed in cancer patients and control subjects. Furthermore, within the patient groups, a set of miRNAs were differentially expressed in exosomal samples obtained before and after chemotherapy treatment. This manuscript demonstrates the potential of exosomal miRNAs for developing noninvasive tests for disease differentiation and treatment monitoring in lung cancer patients.

miR-423-5p serves as a diagnostic indicator and inhibits the proliferation and invasion of ovarian cancer

MicroRNA (miR)-423-5p is a potential target for the diagnosis and therapy of heart failure and cancer. The present study aimed to investigate the expression and role of miR-423-5p in ovarian cancer. miR-423-5p expression in ovarian tissues and plasma collected from ovarian cancer patients and healthy volunteers was analyzed by polymerase chain reaction analysis. In addition, a cell proliferation assay, clonogenic assay and Matrigel-based assay were performed to evaluate the role of miR-423-5p in ovarian cancer cells. The results demonstrated that miR-423-5p was downregulated in ovarian cancer tissues and plasma from ovarian cancer patients, compared with healthy individuals. Of note, miR-423-5p expression in ovarian tissues and plasma was demonstrated to be inversely correlated with ovarian cancer progression. Transfection with miR-423-5p efficiently increased miR-423-5p expression in A2780-s and A2780-cp cells, which had low miR-423-5p expression. Ectopic overexpression of miR-423-5p reduced cell proliferation, colony formation and invasion of ovarian cancer cells. In conclusion, the present study indicated that miR-423-5p may serve as a diagnostic indicator and functions as a tumor suppressor in ovarian cancer.

Establishment of an easy and straight forward heparinase protocol to analyse circulating and myocardial tissue micro-RNA during coronary artery-bypass-graft surgery

Coronary artery-bypass-graft (CABG) surgery is associated with myocardial damage and increased blood concentrations of circulating microRNAs (miRNA). However, whether and to what extent these miRNAs relate to cardiac tissue miRNA expression have not yet been explored. Since plasma miRNA quantification in samples from cardiopulmonary bypass (CPB) patients is severely hampered by heparin, we established and validated successfully a protocol to reliably measure miRNA in 49 heparinized patients undergoing CABG so as to investigate the relationship between circulating and right atrial miRNAs. Plasma and right atrial expression of miR-1, miR-133a, miR-423-5p, and miR-499 were measured before and after CPB, as well as miRNAs in plasma 24 h thereafter. All plasma miRNAs increased significantly with surgery while cardiac tissue expression of only miR-133a (1.4-fold; p = 0.003) and miR-423-5p (1.3 fold; p = 0.025) increased as well. Right atrial and plasma miR-133a expression correlated positively before CPB (r = 0.288, p = 0.045) but miR-499 expression inversely (r = −0.484, p = 0.0004). There was a strong association between plasma miR-133a and miR-499 concentrations and postoperative troponin I concentrations, the marker for myocardial damage. Increased myocardial miR-133a and miR-423-5p expression together with unchanged miR-1 and miR-499 expression might suggest active release of these miRNAs rather than their origin from damaged cells.

Next-generation sequencing-based microRNA profiling of mice testis subjected to transient heat stress

This study aimed to investigate the role of microRNA (miRNA) in heat stress-induced spermatogenic impairment. Testes from 15 adult ICR mice subjected to testicular hyperthermia at 43°C for 30 min and from 15 control mice were collected and pooled into 3 samples. Isolated RNA from these samples was subjected to small RNA high-throughput sequencing, and differentially expressed miRNAs were identified and validated using RT-PCR. The identified miRNAs were further subjected to Gene Ontology and KEGG analyses, which revealed significant enrichment for pathways potentially involved in heat stress-induced spermatogenic impairment. Additionally, a correlation analysis of the relative levels of validated miRNAs with germ cell apoptosis was performed. Of the 11 miRNAs identified as differentially expressed, 8 were validated as consistent with sequencing data. Further analyses suggested that the target genes of those miRNAs were involved in various pathways (e.g., ribosomal, HIF-1, MAPK) that may be critical to heat stress-induced testicular damage. Some identified miRNAs, including miR-449a-3p, miR-92a-1-5p, miR-423-3p, and miR-128-3p, correlated closely with germ cell apoptosis. The study results reveal a detailed miRNA profile of heat stress-induced testicular damage and highlight new and potentially important candidate targets in the process of male infertility.

Down-regulation of microRNA let-7d inhibits the proliferation and invasion of trophoblast cells in preeclampsia

Preeclampsia (PE) is a serious pregnancy complication that continues to adverse effects on mother and the fetus. The study investigated the effect of microRNA let-7d (miR-let-7d) on the proliferation and invasion of trophoblast cells (TC) in PE. In situ hybridization techniques were employed to evaluate the miR-let-7d expressions in the placental tissues from 63 PE patients as well as 65 normal placental tissues. Transfection of pre-let-7d, anti-let-7d, and their corresponding control sequences was performed in TCs obtained from PE. The blank group was composed of TCs no transfection and normal group consisted of normal TCs. Expressions of proliferation and invasion markers in TCs were detected by qRT-PCR. Proliferation, apoptosis, and the invasion ability of the TCs were determined using a CCK-8 assay, flow cytometry, and Transwell assay. In comparison to the normal placental tissues, PE placental tissues exhibited increased levels of let-7d expression. Following transfection of anti-let-7d, when compared with the blank group, the anti-let-7d group displayed increased levels of proliferation ability, expression of proliferation labeling proteins PCNA and Ki67, number of TCs as well as expressions of the invasion related proteins MMP-2, MMP-9, and TIMP-1. In contrast declines in cell apoptosis rate were observed. Compared with the blank group, the changes of the indexes were reversed in the pre-let-7d group. The study provided evidence suggesting that low expression levels of miR-let-7d plays a central role in suppressing apoptosis in addition to promoting the proliferation and invasion of PE TCs.

MicroRNA-423-5p facilitates hypoxia/reoxygenation-induced apoptosis in renal proximal tubular epithelial cells by targeting GSTM1 via endoplasmic reticulum stress

It has been reported that microRNAs (miRs) can regulate renal response to acute injury and members of them are believed to be important in maintenance of renal function and development of renal injury. We investigated the actions of microRNA-423-5p (miR-423-5p) and glutathione-S-transferase (GST) M1 after acute kidney injury. MiR-423-5p was up-regulated and GSTM1 was down-regulated in human kidney (HK-2) cells subjected to hypoxia/reoxygenation (H/R) and in rat kidneys subjected to ischemia/reperfusion (I/R) injury. Dual luciferase assays revealed miR-423-5p binding to the 3′ untranslated region of GSTM1. Proliferation was lower and apoptosis, ER stress and oxidative stress were all higher in H/R-treated HK-2 cells transfected with or without miR-423-5p mimics and GSTM1 siRNA than in the same cells transfected with miR-423-5p inhibitors and a GSTM1 expression vector. Increased miR-423-5p and decreased GSTM1 mRNA and protein levels were observed in rat kidneys on days 1, 2 and 7 after I/R. Levels had normalized by days 14 and 21. On day 3 after treatment, rats receiving I/R or I/R plus miR-423-5p mimics exhibited higher serum creatinine and urea nitrogen levels than rats receiving I/R plus a miR-423-5p inhibitor. MiR-423-5p and lower GSTM1 mRNA and protein levels were higher in the I/R and I/R plus miR-423-5p mimic groups than in the I/R plus miR-423-5p inhibitors group. These findings demonstrate that after acute kidney injury, miR-423-5p induces ER stress and oxidative stress by inhibiting GSTM1and suppresses repair.

Identification of a functional polymorphism affecting microRNA binding in the susceptibility locus 1q25.3 for colorectal cancer

Genome-wide association studies (GWASs) have identified dozens of susceptibility loci for colorectal cancer (CRC). However, most of them lack functional genetic variants and clear biological mechanisms. MicroRNAs (miRNAs) are small noncoding RNAs involved in a variety of physiological and tumorigenic processes. Here we hypothesized that single nucleotide polymorphisms (SNPs) that affect miRNAs biogenesis and binding, could contribute to CRC risk in the Chinese population. To locate miRNA-related SNPs in established GWAS loci, we initially screened out five candidate SNPs using a systematic bioinformatics analysis. Then, we performed a two-stage case-control study consisting of 2347 cases and 3390 controls, and found a positive polymorphism rs1062044, which presented consistently significant associations with CRC in both stages, and with an odds ratio (OR) = 1.32 (95% confidence interval (95%CI) = 1.18-1.49, P = 3.43E-06) under the dominant model in the combined study. Further luciferase reporter gene assays indicated that the variant G allele obviously improved the specific binding between miR-423-5p and the gene LAMC1. These findings suggested that the functional SNP rs1062044 at 1q25.3 might be a genetic modifier for the occurrence and development of CRC.

Differential microRNA expression is associated with androgen receptor expression in breast cancer

The androgen receptor (AR) is frequently expressed in breast cancer; however, its prognostic value remains unclear. AR expression in breast cancer has been associated with improved outcomes in estrogen receptor (ER)‑positive breast cancer compared with ER‑negative disease. Eliminating AR function in breast cancer is critically important for breast cancer progression. However, the mechanism underlying AR regulation remains poorly understood. The study of microRNAs (miRNAs) has provided important insights into the pathogenesis of hormone‑dependent cancer. To determine whether miRNAs function in the AR regulation of breast cancer, the present study performed miRNA expression profiling in AR‑positive and ‑negative breast cancer cell lines. A total of 153 miRNAs were differentially expressed in AR‑positive compared with AR‑negative breast cancer cells; 52 were upregulated and 101 were downregulated. A number of these have been extensively associated with breast cancer cell functions, including proliferation, invasion and drug‑resistance. Furthermore, through pathway enrichment analysis, signaling pathways associated with the prediction targets of the miRNAs were characterized, including the vascular endothelial growth factor and mammalian target of rapamycin signaling pathways. In conclusion, the results of the present study indicated that the expression of miRNAs may be involved in the mechanism underlying AR regulation of breast cancer, and may improve understanding of the role of AR in breast cancer.

Analysis of liver and gill miRNAs of Larimichthys crocea against Cryptocryon irritans challenge

The white-spot disease caused by marine ciliate Cryptocryon irritans hindered the sustainable development of large yellow croaker Larimichthys crocea industry. Better understandings about the parasite-host interactions in the molecular level will facilitate the prevention of mass mortality of the L. crocea caused by white-spot disease. MicroRNAs (miRNAs) are a class of small RNA molecules about 20-22 nucleotides which post-transcriptionally regulated many protein-coding genes and involved in many biological processes, especially in host-pathogen responses. In this study, we identified known and novel miRNAs in the gill and liver of L. crocea challenged by C. irritans by high throughput sequencing using Solexa technology. The data were further studied to screen differentially expressed miRNAs, and predict their target genes. The differential expression (p < 0.05) between libraries was observed in 103 miRNAs in liver tissue, among which 65 and 38 were conserved and novel miRNAs, 67 and 36 were up- and down-regulated miRNAs. While in gill tissue, 122 significant differentially expressed miRNAs were identified, among which 83 and 39 were conserved and novel miRNAs, 79 and 43 were up- and down-regulated miRNAs. In addition, these differentially expressed miRNAs target a series of genes which involved in many important biological processes including immune response. Here via deep sequencing, we for the first time characterize L. crocea miRNAs in response to C. irritans challenge, the results should help for better understandings about the immune response of the L. crocea under C. irritans challenge.