miR-374a promotes cell proliferation, migration and invasion by targeting SRCIN1 in gastric cancer

GATA2‑miR‑374a axis promotes vascular smooth muscle cells proliferation, migration via targeting circTADA2A/RORA axis

Evidence has shown that microRNAs (miRNAs/miRs) play key roles in biological functions of vascular smooth muscle cells (VSMCs). However, the role of miR-374a in VSMCs remains to be elucidated. The present study aimed to explore the influence of miR-374a on VSMCs and its molecular mechanism. The expression level of miR-374a was measured by reverse transcription-quantitative (RT-q) PCR. MTT and Transwell assay were employed to assess the role of miR-374a in proliferation and migration of VSMCs. To order to determine miR-374a targets, a dual-luciferase reporter assay was conducted, which was further verified by rescue experiments. Chromatin Immunoprecipitation Assay and JASPAR databases were applied to explore the regulatory association between GATA binding protein 2 (GATA2) and miR-374a. Western blotting or RT-qPCR were employed to detect the protein expression levels of GATA2 or RAR-related orphan receptor A (RORA). The present study found that miR-374a was elevated in VSMCs following treatment with platelet-derived growth factor-BB (PDGF-BB) compared with that in control group. In addition, the results demonstrated that a higher expression of a miR-374a could promote proliferation and migration of VSMCs while miR-374a inhibitor suppressed the PDGF-BB-induced proliferation and migration of VSMCs in vitro. Furthermore, circTADA2A bound to miR-374a and then upregulated RORA expression, which resulted in inhibition in VSMCs proliferation and migration. On the other hand, the result indicated that GATA2 overexpression could augment the proliferation, migration of PDGF-bb-induced VSMCs, which could be rescued by miR-374a inhibitor. The findings suggested that the GATA2/circTADA2A-miR-374a axis promoted the proliferation and migration of VSMCs by targeting RORA, which were closely related to atherosclerosis (AS). Thus the results might offer a new therapeutic target for AS.

Ficus hirta Vahl. alleviate LPS induced apoptosis via down-regulating of miR-411 in orange-spotted grouper (Epinephelus coioides) spleen cell

Ficus hirta Vahl. (FhV) has been shown to have antimicrobial and antiviral efficacy. To further ascertain the pharmacological properties of FhV., and to search for alternatives to antibiotics. An in vitro experiment was carried out to evaluate what influence FhV. would have on LPS-induced apoptosis. In this study, Fas, an apoptosis receptor, was cloned, which included a 5'-UTR of 39 bp, an ORF of 951 bp, a protein of 316 amino acids, and a 3'-UTR of 845 bp. EcFas was most strongly expressed in the spleen tissue of orange-spotted groupers. In addition, the apoptosis of fish spleen cells induced by LPS was concentration-dependent. Interestingly, appropriate concentrations of FhV. alleviated LPS-induced apoptosis. Inhibition of miR-411 further decreased the inhibitory effect of Fas on apoptosis, which reduced Bcl-2 expression and mitochondrial membrane potential, enhanced the protein expression of Bax and Fas. More importantly, the FhV. could activate miR-411 to improve this effect. In addition, luciferase reporter assays showed that miR-411 binds to Fas 3'-UTR to inhibit Fas expression. These findings provide evidence that FhV. alleviates LPS-induced apoptosis by activating miR-411 to inhibit Fas expression and, therefore, provided possible strategies for bacterial infections in fish.

Celastrol inhibits gastric cancer cell proliferation, migration, and invasion via the FOXA1/CLDN4 axis

Background

Celastrol is a biologically active compound with potent anti-tumor properties. However, the mechanism of action of celastrol in gastric cancer (GC) has not been fully elucidated.

Methods

To explore the specific mechanism of the effect of celastrol on GC cells. GC cells were transfected with forkhead box A1 (FOXA1) or claudin 4 (CLDN4), or short hairpin RNA targeting FOXA1. The expressions of FOXA1 and CLDN4 in GC cells were determined by quantitative reverse transcription PCR and Western blot. GC cell proliferation, migration, and invasion were measured by MTT assay and Transwell assay, respectively. The interaction between CLDN4 and FOXA1 was examined by luciferase reporter assay.

Resluts

CLDN4 and FOXA1 were upregulated in GC cells. Celastrol prevented the proliferation, migration, and invasion of GC cells by downregulating FOXA1 expression. Overexpression of FOXA1 or CLDN4 accelerated GC progression. CLDN4 overexpression also induced the activation of the expressions of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway. FOXA1 enhanced the transcription of CLDN4.

Conclusion

Celastrol regulated GC progression via targeting the FOXA1/CLDN4 axis to impede the PI3K/AKT pathway. Our study proposed a new mechanism of how celastrol inhibited tumorigenesis in GC, which provided evidence for the potential use of celastrol for anti-GC treatment.

Dynamic Regulation Genes at Microtubule Plus Ends: A Novel Class of Glioma Biomarkers

Simple Summary

Microtubule plus-end-related genes (MPERGs) encode a group of proteins that specifically aggregate at the microtubule plus ends to play critical biological roles in the cell cycle, cell movement, ciliogenesis, and neuronal development by coordinating microtubule assembly and dynamics; however, the MPERG correlations and their clinical significance in glioma are not fully understood. This study is the first to systematically analyze and define a seven-gene signature (CTTNBP2, KIF18A, NAV1, SLAIN2, SRCIN1, TRIO, and TTBK2) and nomogram model closely associated with clinical factors and the tumor microenvironment as a reliable and independent prognostic biomarker to guide personalized choices of immunotherapy and chemotherapy for glioma patients.

Abstract

Glioma is the most prevalent and aggressive primary nervous system tumor with an unfavorable prognosis. Microtubule plus-end-related genes (MPERGs) play critical biological roles in the cell cycle, cell movement, ciliogenesis, and neuronal development by coordinating microtubule assembly and dynamics. This research seeks to systematically explore the oncological characteristics of these genes in microtubule-enriched glioma, focusing on developing a novel MPERG-based prognostic signature to improve the prognosis and provide more treatment options for glioma patients. First, we thoroughly analyzed and identified 45 differentially expressed MPERGs in glioma. Based on these genes, glioma patients were well distinguished into two subgroups with survival and tumor microenvironment infiltration differences. Next, we further screened the independent prognostic genes (CTTNBP2, KIF18A, NAV1, SLAIN2, SRCIN1, TRIO, and TTBK2) using 36 prognostic-related differentially expressed MPERGs to construct a signature with risk stratification and prognostic prediction ability. An increased risk score was related to the malignant progression of glioma. Therefore, we also designed a nomogram model containing clinical factors to facilitate the clinical use of the risk signature. The prediction accuracy of the signature and nomogram model was verified using The Cancer Genome Atlas and Chinese Glioma Genome Atlas datasets. Finally, we examined the connection between the signature and tumor microenvironment. The signature positively correlated with tumor microenvironment infiltration, especially immunoinhibitors and the tumor mutation load, and negatively correlated with microsatellite instability and cancer stemness. More importantly, immune checkpoint blockade treatment and drug sensitivity analyses confirmed that this prognostic signature was helpful in anticipating the effect of immunotherapy and chemotherapy. In conclusion, this research is the first study to define and validate an MPERG-based signature closely associated with the tumor microenvironment as a reliable and independent prognostic biomarker to guide personalized choices of immunotherapy and chemotherapy for glioma patients.

miRNAs derived from plasma small extracellular vesicles predict organo-tropic metastasis of gastric cancer

BACKGROUND

Peritoneum, liver and lymph node are the most common metastatic sites of gastric cancer (GC). Biomarkers for GC's organo-tropic metastasis remained largely unknown, which was investigated in this study from the perspective of small extracellular vesicle (sEV)-derived miRNAs.

METHODS

Plasma from treatment-naïve GC patients including no metastasis (M0), peritoneal metastasis (PM), hepatic metastasis (HM) and distant lymph node metastasis (dLNM)) were divided into one discovery (N = 40), one training (N = 40) and one validating cohort (N = 86), then assessed by sEV-miRNA-sequencing and sEV-miRNA-qPCR. Functional explorations were also performed for verification.

RESULTS

The expression profiles of sEV-miRNAs varied greatly across different metastatic patterns. Based on logistic regression models, we constructed signatures for M0 (hsa-miR-186-5p/hsa-miR-200c-3p/hsa-miR-429/hsa-miR-5187-5p/hsa-miR-548ae-5p), PM (hsa-miR-200c-3p/hsa-miR-429), HM (hsa-miR-200c-3p/hsa-miR-429) and dLNM (hsa-miR-324-5p/hsa-miR-374a-5p/hsa-miR-429/hsa-miR-548ae-5p). These signatures vigorously characterized organo-tropic metastasis (all displaying AUC > 0.8, consistency ≥ 75%), and effectively conjectured the risk of future metastasis within 5 years (accuracy 45.5% for occurrence, 70% for organotropism, P = 0.002 for prognostic diversity). Additionally, we explored these seven biomarker miRNAs' impact on GC's in vitro motility and discussed their potential involvement in cancer-related biological processes and pathways.

CONCLUSIONS

Our work highlighted that plasma sEV-miRNAs powerfully characterized and predicted the organo-tropic metastasis of GC and provided new insight into the applications of sEV-based liquid biopsy in clinical practice.

Multimerin-1 and cancer: a review

Multimerin-1 (MMRN1) is a platelet protein with a role in haemostasis and coagulation. It is also present in endothelial cells (ECs) and the extracellular matrix (ECM), where it may be involved in cell adhesion, but its molecular functions and protein–protein interactions in these cellular locations have not been studied in detail yet. In recent years, MMRN1 has been identified as a differentially expressed gene (DEG) in various cancers and it has been proposed as a possible cancer biomarker. Some evidence suggest that MMRN1 expression is regulated by methylation, protein interactions, and non-coding RNAs (ncRNAs) in different cancers. This raises the questions if a functional role of MMRN1 is being targeted during cancer development, and if MMRN1’s differential expression pattern correlates with cancer progression. As a result, it is timely to review the current state of what is known about MMRN1 to help inform future research into MMRN1’s molecular mechanisms in cancer.

MicroRNA-30c-2-3p targets STRIP2 to suppress malignant progression of gastric cancer cells

MicroRNA plays a crucial part in genesis and development of gastric cancer (GC). We uncovered that microRNA-30c-2-3p was down-regulated in GC tissue and cell lines. Suppression of microRNA-30c-2-3p promoted progression of GC cells in vitro. STRIP2 was confirmed as a target for microRNA-30c-2-3p. MicroRNA-30c-2-3p overexpression remarkably suppressed cell malignant behaviors, while reintroduction of STRIP2 partially restored the anticancer effect of microRNA-30c-2-3p. Taken together, these findings suggested that microRNA-30c-2-3p acted as a candidate tumor suppressor in GC by directly targeting STRIP2. Therefore, microRNA-30c-2-3p can be used as a towardly GC therapeutic target.

Exosomal miRNA-205 promotes breast cancer chemoresistance and tumorigenesis through E2F1

Breast cancer (BC) is a common malignant tumor in females. The challenge in treating BC is overcoming chemoresistance. Exosome-mediated transfer of miRNAs is a molecule-shuttle in intercellular communication. Thus, we aimed to investigate whether exosomal miRNA-205 could affect chemoresistance and tumorigenesis in recipient tumor cells and to elucidate the underlying mechanism in vivo and in vitro. Microarray and qRT-PCR assays demonstrated that miRNA-205 was upregulated in tamoxifen resistance MCF-7/TAMR-1 (M/T) cells and M/T cell-derived exosomes (M/T-Exo). The M/T-Exo was internalized by human BC cells (BCCs), causing increased expression of miRNA-205 in BCCs. Coculturing with M/T-Exo promoted tamoxifen resistance, proliferation, migration, and invasion while suppressed apoptosis in recipient BCCs, which were associated with activating the caspase pathway and phosphorylating Akt. Luciferase reporter assays showed that miRNA-205 directly targeted E2F Transcription Factor 1 (E2F1) in BCCs. Furthermore, knockdown of miRNA-205 or overexpression of E2F1 reversed the roles of M/T-Exo in BCCs. In vivo experiments showed that the intratumoral injection of M/T-Exo caused greater tamoxifen resistance and larger tumor size relative to mice treated with miRNA-205-knockdown or E2F1-overexpressing BCCs. Together, the results suggest that exosomal miRNA-205 may promote tamoxifen resistance and tumorigenesis in BC through targeting E2F1 in vivo and in vitro.

The p140Cap adaptor protein as a molecular hub to block cancer aggressiveness

The p140Cap adaptor protein is a scaffold molecule encoded by the SRCIN1 gene, which is physiologically expressed in several epithelial tissues and in the neurons. However, p140Cap is also strongly expressed in a significant subset of cancers including breast cancer and neuroblastoma. Notably, cancer patients with high p140Cap expression in their primary tumors have a lower probability of developing a distant event and ERBB2-positive breast cancer sufferers show better survival. In neuroblastoma patients, SRCIN1 mRNA levels represent an independent risk factor, which is inversely correlated to disease aggressiveness. Consistent with clinical data, SRCIN1 gain or loss of function mouse models demonstrated that p140Cap may affect tumor growth and metastasis formation by controlling the signaling pathways involved in tumorigenesis and metastatic features. This study reviews data showing the relevance of SRCIN1/p140Cap in cancer patients, the impact of SRCIN1 status on p140Cap expression, the specific mechanisms through which p140Cap can limit cancer progression, the molecular functions regulated by p140Cap, along with the p140Cap interactome, to unveil its key role for patient stratification in clinics.

MicroRNA expression profiles in the esophagus of children with caustic stenosis: A pathway towards esophageal cancer?

BACKGROUND

Eighty percent of caustic ingestions occur in children and esophageal neoplasms may develop as a late complication of such injury. The identification of biomarkers is a promising strategy to improve early diagnosis of esophageal cancer or caustic lesions that are at an increased risk of progression.

STUDY DESIGN/AIMS

This study aimed at identifying global microRNA (miRNA) expression changes in esophageal mucosa from children with caustic stenosis. The study included 27 biopsy samples from 15 patients. Samples were divided into two groups, according to the time elapsed after injury (N = 15 in Group A, with less than five years of follow-up and N = 12 in Group B, with more than five years of follow-up). miRNA expression profiles were determined in each lesion, compared with normal esophageal tissues from control group. We used the TaqMan Human MicroRNA Arrays (Thermo Fisher) platform. Furthermore, bioinformatic algorithms were used to identify miRNA target genes and biological pathways including miRNAs and their target genes potentially associated with esophageal disease.

RESULTS

Thirteen miRNAs were significantly deregulated (9 over- and 4 underexpressed) in patients from Group A. In patients from Group B, two miRNAs were over- and two were underexpressed. Of note, miR-374 and miR-574 were deregulated in Group B patients and have been linked to esophageal tumorigenesis. We identified signal transduction and transcription factor networks with genes strongly related to development and progression of esophageal cancer.

CONCLUSION

miRNAs identified here contribute to a better understanding of pathways associated with malignant transformation from caustic stenosis to neoplastic lesions. This study may serve as a basis for validation of miRNAs, including miR-374 and miR-574, as potential biomarkers of early cancer detection.

SRCIN1 Regulated by circCCDC66/miR-211 Is Upregulated and Promotes Cell Proliferation in Non-Small-Cell Lung Cancer

The incidence and mortality of lung cancer were extremely high. The present study showed that SRCIN1 was an oncogene in non-small-cell lung cancer (NSCLC). Public dataset analysis showed SRCIN1 was significantly overexpressed in NSCLC samples. Also, we found that NSCLC patients with higher SRCIN1 expression had shorter OS time by analyzing TCGA, Kaplan-Meier Plotter, GSE30219, GSE50081, and GSE19188 databases. Overexpression or knockdown of SRCIN1 significantly induced or reduced A549 and H1299 cell proliferation. Furthermore, we found SRCIN1 was directly targeted by miR-211. Overexpression or knockdown of miR-211 suppressed or induced SRCIN1 levels in NSCLC. Moreover, we found that miR-211 affected NSCLC cell proliferation through SRCIN1. Previous studies demonstrated that circRNAs could act as miRNA sponges in cancer cells. In this study, we showed that knockdown of circCCDC66 induced expression of miR-211. Luciferase assay demonstrated that miR-211 suppressed the activity of luciferase reporter-contained circCCDC66 sequences. Moreover, knockdown of circCCDC66 significantly inhibited SRCIN1 levels in both A549 and H1299 cells. These results showed that circCCDC66 acted as a miRNA sponge to affect the miR-211/SRCIN1 axis. Of note, we for the first time revealed that circCCDC66 suppression reduced cell proliferation by about 65% in A549 and by about 40% in H1299 cells. We thought this study could provide novel potential biomarkers for NSCLC.

Temporally Altered miRNA Expression in a Piglet Model of Hypoxic Ischemic Brain Injury

Hypoxic ischemic encephalopathy (HIE) is the most frequent cause of acquired infant brain injury. Early, clinically relevant biomarkers are required to allow timely application of therapeutic interventions. We previously reported early alterations in several microRNAs (miRNA) in umbilical cord blood at birth in infants with HIE. However, the exact timing of these alterations is unknown. Here, we report serial changes in six circulating, cross-species/bridging biomarkers in a clinically relevant porcine model of neonatal HIE with functional analysis. Six miRNAs—miR-374a, miR-181b, miR-181a, miR-151a, miR-148a and miR-128—were significantly and rapidly upregulated 1-h post-HI. Changes in miR-374a, miR-181b and miR-181a appeared specific to moderate-severe HI. Histopathological injury and five miRNAs displayed positive correlations and were predictive of MRS Lac/Cr ratios. Bioinformatic analysis identified that components of the bone morphogenic protein (BMP) family may be targets of miR-181a. Inhibition of miR-181a increased neurite length in both SH-SY5Y cells at 1 DIV (days in vitro) and in primary cultures of rat neuronal midbrain at 3 DIV. In agreement, inhibition of miR-181a increased expression of BMPR2 in differentiating SH-SY5Y cells. These miRNAs may therefore act as early biomarkers of HIE, thereby allowing for rapid diagnosis and timely therapeutic intervention and may regulate expression of signalling pathways vital to neuronal survival.

Identification of Novel microRNA Prognostic Markers Using Cascaded Wx, a Neural Network-Based Framework, in Lung Adenocarcinoma Patients

The evolution of next-generation sequencing technology has resulted in a generation of large amounts of cancer genomic data. Therefore, increasingly complex techniques are required to appropriately analyze this data in order to determine its clinical relevance. In this study, we applied a neural network-based technique to analyze data from The Cancer Genome Atlas and extract useful microRNA (miRNA) features for predicting the prognosis of patients with lung adenocarcinomas (LUAD). Using the Cascaded Wx platform, we identified and ranked miRNAs that affected LUAD patient survival and selected the two top-ranked miRNAs (miR-374a and miR-374b) for measurement of their expression levels in patient tumor tissues and in lung cancer cells exhibiting an altered epithelial-to-mesenchymal transition (EMT) status. Analysis of miRNA expression from tumor samples revealed that high miR-374a/b expression was associated with poor patient survival rates. In lung cancer cells, the EMT signal induced miR-374a/b expression, which, in turn, promoted EMT and invasiveness. These findings demonstrated that this approach enabled effective identification and validation of prognostic miRNA markers in LUAD, suggesting its potential efficacy for clinical use.

Historical retrospective of the oncogene and new perspectives (Review)

Since its first discovery as part of the Rous sarcoma virus (RSV) genome, the c-SRC (SRC) proto-oncogene has been proved a key regulator of cancer development and progression, and thus it has been highlighted as an attractive target for anti-cancer therapeutic strategies. Though the exact mechanisms of its action are still not fully understood, SRC protein mediates crucial normal cell functions, such as cell development, proliferation and survival, and its dysregulation is considered as an oncogenic signature and a driving force for cancer initiation. In the present review, we present a flashback to the history of the Src research, while focusing on the most important milestones in the field. Moreover, we investigate the proposed regulatory mechanisms and molecules that mediate its action in order to designate putative therapeutic targets and useful prognostic and/or diagnostic tools. Furthermore, we present and discuss existing therapeutic approaches that are explored in clinical settings.

Expression profiling of microRNAs and isomiRs in conventional central chondrosarcoma

Conventional central chondrosarcoma (CCC) is a malignant bone tumor that is characterized by the production of chondroid tissue. Since radiation therapy and chemotherapy have limited effects on CCC, treatment of most patients depends on surgical resection. This study aimed to identify the expression profiles of microRNAs (miRNAs) and isomiRs in CCC tissues to highlight their possible participation to the regulation of pathways critical for the formation and growth of this type of tumor. Our study analyzed miRNAs and isomiRs from Grade I (GI), Grade II (GII), and Grade III (GIII) histologically validated CCC tissue samples. While the different histological grades shared a similar expression profile for the top abundant miRNAs, we found several microRNAs and isomiRs showing a strong different modulation in GII + GIII vs GI grade samples and their involvement in tumor biology could be consistently hypothesized. We then in silico validated these differently expressed miRNAs in a larger chondrosarcoma public dataset and confirmed the expression trend for 17 out of 34 miRNAs. Our results clearly suggests that the contribution of miRNA deregulation, and their targeted pathways, to the progression of CCC could be relevant and strongly indicates that when studying miRNA deregulation in tumors, not only the canonical miRNAs, but the whole set of corresponding isomiRs should be taken in account. Improving understanding of the precise roles of miRNAs and isomiRs over the course of central chondrosarcoma progression could help identifying possible targets for precision medicine therapeutic intervention.

Isoliquiritigenin Derivative Regulates miR-374a/BAX Axis to Suppress Triple-Negative Breast Cancer Tumorigenesis and Development

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that accounts for the largest proportion of breast cancer-related deaths. Thus, it is imperative to search for novel drug candidates with potent anti-TNBC effects. Recent studies suggest that isoliquiritigenin (ISL) can significantly suppress the growth, migration, and invasion of breast cancer cells. We previously synthesized ISL derivatives and found that 3′,4′,5′,4″-tetramethoxychalcone (TMC) inhibits TNBC cell proliferation to a greater degree than ISL. The present study aimed to investigate the mechanisms underlying the anti-TNBC effects of TMC in vitro and in vivo. We show that TMC significantly inhibits the proliferative, migratory, and invasive abilities of MDA-MB-231 and BT549 cells. TMC induces apoptosis through the upregulation of Bax and downregulation of Bcl-2. PCR arrays demonstrate a significant decrease in miR-374a expression in TNBC cells after 24-h TMC treatment. MiR-374a is overexpressed in TNBC cells and has oncogenic properties. Real-time PCR analysis confirmed that TMC inhibits miR-374a in a dose-dependent manner, and luciferase assays confirmed that BAX is targeted by miR-374a. Further, we show that TMC increases Bax protein and mRNA levels by inhibiting miR-374a. TMC also attenuates TNBC tumor volumes and weights in vivo. These results demonstrate that TMC inhibits TNBC cell proliferation, foci formation, migration, invasion, and tumorigenesis, suggesting its potential to serve as a novel drug for treating TNBC through miR-374a repression.

Long Non-Coding RNA MAGI2-AS3 is a New Player with a Tumor Suppressive Role in High Grade Serous Ovarian Carcinoma

High-Grade Serous Ovarian Carcinoma (HGSC) is the most incidental and lethal subtype of epithelial ovarian cancer (EOC) with a high mortality rate of nearly 65%. Recent findings aimed at understanding the pathogenesis of HGSC have attributed its principal source as the Fallopian Tube (FT). To further comprehend the exact mechanism of carcinogenesis, which is still less known, we performed a transcriptome analysis comparing FT and HGSC. Our study aims at exploring new players involved in the development of HGSC from FT, along with their signaling network, and we chose to focus on non-coding RNAs. Non-coding RNAs (ncRNAs) are increasingly observed to be the major regulators of several cellular processes and could have key functions as biological markers, as well as even a therapeutic approach. The most physiologically relevant and significantly dysregulated non-coding RNAs were identified bioinformatically. After analyzing the trend in HGSC and other cancers, MAGI2-AS3 was observed to be an important player in EOC. We assessed its tumor-suppressive role in EOC by means of various assays. Further, we mapped its signaling pathway using its role as a miRNA sponge to predict the miRNAs binding to MAGI2AS3 and showed it experimentally. We conclude that MAGI2-AS3 acts as a tumor suppressor in EOC, specifically in HGSC by sponging miR-15-5p, miR-374a-5p and miR-374b-5p, and altering downstream signaling of certain mRNAs through a ceRNA network.

MicroRNA-665 promotes the proliferation of ovarian cancer cells by targeting SRCIN1

Recent studies have discovered several microRNAs (miRNAs/miRs) as biomarkers for the prediction of ovarian cancer by detecting miRNA profiles in serum samples from healthy volunteers and patients with ovarian cancer. However, whether and how these miRNAs are involved in tumorigenesis is not known. In the present study, the expression of miR-665, a recently discovered biomarker for ovarian cancer, was upregulated in tumor tissues from patients with ovarian cancer compared with normal tissues. Inhibition of miR-665 inhibited cell proliferation ability and inactivated MAPK/ERK signaling of ovarian cancer cells. Using bioinformatics analysis, Src kinase signaling inhibitor 1 (SRCIN1) was predicted as a potential target gene of miR-665. Reverse transcription-quantitative PCR and western blotting showed that SRCIN1 expression was repressed by miR-665 in ovarian cancer cells. In addition, a dual luciferase activity assay showed that SRCIN1 was a target gene of miR-665. Silencing of SRCIN1 could reverse the cell growth arrest, which was induced by the miR-665 inhibitor. Moreover, miR-665 levels were negatively correlated with SRCIN1 mRNA levels in tumor tissues from patients with ovarian cancer. In conclusion, the present data suggested that miR-665 functioned as an oncogene in ovarian cancer by directly repressing the expression of SRCIN1.

MicroRNA Changes in Firefighters

Objectives:

Firefighters have elevated cancer incidence and mortality rates. MicroRNAs play prominent roles in carcinogenesis, but have not been previously evaluated in firefighters.

Methods:

Blood from 52 incumbent and 45 new recruit nonsmoking firefighters was analyzed for microRNA expression, and the results adjusted for age, obesity, ethnicity, and multiple comparisons.

Results:

Nine microRNAs were identified with at least a 1.5-fold significant difference between groups. All six microRNAs with decreased expression in incumbent firefighters have been reported to have tumor suppressor activity or are associated with cancer survival, and two of the three microRNAs with increased expression in incumbent firefighters have activities consistent with cancer promotion, with the remaining microRNA associated with neurological disease.

Conclusion:

Incumbent firefighters showed differential microRNA expression compared with new recruits, providing potential mechanisms for increased cancer risk in firefighters.

miR-374a-5p: A New Target for Diagnosis and Drug Resistance Therapy in Gastric Cancer

Chemoresistance is one of the causes associated with poor prognosis in gastric cancer. MicroRNAs (miRNAs) are important regulators of chemoresistance. Exosome-mediated delivery of anti-cancer molecules and drugs have emerged as a new approach for cancer therapy. We first examined the expression of miR-374a-5p in gastric cancer serum by qRT-PCR and explored the clinicopathological parameters. We then performed in vitro cell and molecular studies, including CCK-8 assay, flow cytometry, qRT-PCR, and western blot, to determine the roles of miR-374a-5p in gastric cancer chemoresistance and identified its downstream target by luciferase reporter assay. We also used in vivo animal studies to evaluate the therapeutic efficacy of miR-374a-5p inhibitor and exosome-mediated delivery of miR-374a-5p inhibitor in gastric cancer. miR-374a-5p expression level was elevated in gastric cancer serum, and its upregulation predicted poor prognosis. miR-374a-5p overexpression promoted while miR-374a-5p knockdown inhibited gastric cancer chemoresistance in vitro and in vivo. miR-374a-5p bound to Neurod1 to antagonize its effect on chemoresistance. Exosome-mediated delivery of miR-374a-5p inhibitor could increase Neurod1 expression, promote cell apoptosis, and suppress chemoresistance. miR-374a-5p had a promoting role in gastric cancer chemoresistance, which would provide a novel biomarker for gastric cancer diagnosis and prognosis and offer a potential target for gastric cancer drug resistance therapy.

The SRCIN1/p140Cap adaptor protein negatively regulates the aggressiveness of neuroblastoma

Neuroblastoma is the most common extra-cranial pediatric solid tumor, responsible for 13–15% of pediatric cancer death. Its intrinsic heterogeneity makes it difficult to target for successful therapy. The adaptor protein p140Cap/SRCIN1 negatively regulates tumor cell features and limits breast cancer progression. This study wish to assess if p140Cap is a key biological determinant of neuroblastoma outcome. RNAseq profiles of a large cohort of neuroblastoma patients show that SRCIN1 mRNA levels are an independent risk factor inversely correlated to disease aggressiveness. In high-risk patients, CGH+SNP microarray analysis of primary neuroblastoma identifies SRCIN1 as frequently altered by hemizygous deletion, copy-neutral loss of heterozygosity, or disruption. Functional experiments show that p140Cap negatively regulates Src and STAT3 signaling, affects anchorage-independent growth and migration, in vivo tumor growth and spontaneous lung metastasis formation. p140Cap also increases sensitivity of neuroblastoma cells to doxorubicin and etoposide treatment, as well as to a combined treatment with chemotherapy drugs and Src inhibitors. Our functional findings point to a causal role of p140Cap in curbing the aggressiveness of neuroblastoma, due to its ability to impinge on specific molecular pathways, and to sensitize cells to therapeutic treatment. This study provides the first evidence that the SRCIN1/p140Cap adaptor protein is a key player in neuroblastoma as a new independent prognostic marker for patient outcome and treatment. Altogether, these data highlight the potential clinical impact of SRCIN1/p140Cap expression in neuroblastoma tumors, in terms of reducing cytotoxic effects of chemotherapy, one of the main issues for pediatric tumor treatment.

miR-373 promotes neuroblastoma cell proliferation, migration, and invasion by targeting SRCIN1

Introduction

Previous studies have shown that miR-373 functions as either a tumor suppressor or an oncogene depending on which type of cancer it’s operating in. However, the functional role of miR-373 in neuroblastoma (NB) remains largely unclear. 

Methods

Expression of miR-373 and SRC kinase signaling inhibitor 1 (SRCIN1) in 20 metastatic and 20 primary NB tissues was detected by quantitative real-time PCR (qRT-PCR) and Western blotting. MTT assay, flow cytometry analysis and transwell migration and invasion assays were performed to evaluate the influence of miR-373 inhibition on the growth, migration and invasion of NB cells, respectively. In vivo experiment was applied to determine the effect of miR-373 inhibition on tumor growth. Dual-luciferase reporter assay was used to confirm the interaction between miR-373 and SRCIN1.

Results

We observed a significant increase in the expression of miR-373 in metastatic NB samples compared with primary NB samples, and this was inversely correlated with SRCIN1 expression. Functional studies revealed that depletion of miR-373 inhibited in vitro NB cell growth, migration and invasion, and also suppressed tumor growth in an in vivo mouse model. Moreover, we identified that SRCIN1 was a direct and functional target gene of miR-373. Silencing of SRCIN1 partially rescued the antimiR-373-mediated inhibition of cell growth, migration and invasion.

Conclusion

The data from our study verified a potential oncogenic role of miR-373 in NB cells that occurs through direct targeting SRCIN1. The newly identified miR-373/SRCIN1 axis represents a new potential candidate for therapeutic intervention of malignant NB.

microRNA-374 inhibits proliferation and promotes apoptosis of mouse melanoma cells by inactivating the Wnt signalling pathway through its effect on tyrosinase

Melanoma is one of the most malignant skin tumours with constantly increasing incidence worldwide. Previous studies have demonstrated that microRNA‐374 (miR‐374) is a novel biomarker for cancer therapy. Therefore, this study explores whether miR‐374 targeting tyrosinase (TYR) affects melanoma and its underlying mechanism. We constructed subcutaneous melanoma models to carry out the following experiments. The cells were transfected with a series of miR‐374 mimics, miR‐374 inhibitors or siRNA against TYR. Dual luciferase reporter gene assay was used for the verification of the targeting relationship between miR‐374 and TYR. Reverse transcription quantitative polymerase chain reaction and western blot analysis were conducted to determine the expression of miR‐374, TYR, β‐catenin, B‐cell leukaemia 2 (Bcl‐2), Bcl‐2 associated X protein (Bax), Low‐density lipoprotein receptor‐related protein 6 (LRP6), Leucine‐rich repeat G protein‐coupled receptor 5 (LGR5) and CyclinD1. Cell proliferation, migration, invasion, cell cycle distribution and apoptosis were evaluated using cell counting kit‐8 assay, scratch test, transwell assay and flow cytometry respectively. TYR was proved as a putative target of miR‐374 as the evidenced by the result. It was observed that up‐regulated miR‐374 or down‐regulated TYR increased expression of Bax and decreased expressions of TYR, β‐catenin, LRP6, Bcl‐2, CyclinD1 and LGR5, along with diminished cell proliferation, migration, invasion and enhanced apoptosis. Meanwhile, cells with miR‐374 inhibitors showed an opposite trend. These findings indicated that up‐regulated miR‐374 could inhibit the expression of TYR to suppress cell proliferation, migration, invasion and promote cell apoptosis in melanoma cells by inhibiting the Wnt signalling pathway.

Neferine inhibits MDA-MB-231 cells growth and metastasis by regulating miR-374a/FGFR-2

BACKGROUND

Neferine (NEF) is a major bisbenzylisoquinline alkaloid mainly exists in the seed embryo of Nelumbo nucifera (Gaertn.) that possesses anti-tumor effects. Our study designed to check the effect of NEF on breast cancer MDA-MB-231 cells and further explore the potential mechanism.

METHODS

MDA-MB-231 cells were administrated with various dosages of NEF for 24 h after which cell viability was measured. The effects of NEF on cell proliferation, apoptosis, migration and invasion were assessed by BrdU staining, flow cytometry assay and Transwell assay. Western blot was utilized to assess the accumulation of proteins related with proliferation, apoptosis, metastasis, PI3K/AKT and MEK/ERK pathways.

RESULTS

Viability was efficiently reduced by NEF in a dose-dependent manner. NEF (8 μM) significantly suppressed cell proliferation, migration and invasion but enhanced apoptosis in MDA-MB-213 cells. Interestingly, NEF suppressed miR-374a expression and miR-374a mediated the inhibitory effect of NEF. Moreover, miR-374a positively regulated FGFR-2 expression and FGFR-2 overexpression impeded the effect of NEF on MDA-MB-213 cells. FGFR-2 overexpression abolished the suppressive effect of NEF on PI3K/AKT and MEK/ERK pathways.

CONCLUSION

We found that NEF possessed the anti-growth and anti-metastasis effect on MDA-MB-231 cells through regulating miR-374a/FGFR-2, which might provide new insight for breast cancer management.

MicroRNA-374a Governs Aggressive Cell Behaviors of Glioma by Targeting Prokineticin 2

MicroRNA-374a has been abnormally expressed in several cancer types; however, its role in glioma remains unclear. Therefore, we aimed to investigate whether microR-374a participated in the progression of glioma. Expression of microR-374a in glioma cell lines and normal cell line was measured by quantitative real-time polymerase chain reaction. Luciferase reporter assay and Western blot were used to detect the targets of microR-374a. In vitro functional experiments were conducted to investigate the biological role of microR-374a. Low expression of microR-374a was found in glioma cell lines. Prokineticin 2 was identified as a direct target of microR-374a in glioma. Investigations on the mechanisms related to glioma progression showed that microR-374a inhibited glioma cell proliferation, cell cycle progression, and cell invasion through targeting Prokineticin 2. Taken together, these results revealed that microR-374a functions as tumor suppressor by targeting Prokineticin 2, suggesting it might be a novel therapeutic target for glioma.

MicroRNA-510 Plays Oncogenic Roles in Non-Small Cell Lung Cancer by Directly Targeting SRC Kinase Signaling Inhibitor 1

An increasing number of studies have demonstrated that microRNAs (miRNAs) may play key roles in various cancer carcinogenesis and progression, including non-small cell lung cancer (NSCLC). However, the expressions, roles, and mechanisms of miR-510 in NSCLC have, up to now, been largely undefined. In vivo assay showed that miR-510 was upregulated in NSCLC tissues compared with that in adjacent nontumor lung tissues. miR-510 expression was significantly correlated with TNM stage and lymph node metastasis. In vitro assay indicated that expressions of miR-510 were also increased in NSCLC cell lines. Downregulation of miR-510 suppressed NSCLC cell proliferation and invasion in vitro. We identified SRC kinase signaling inhibitor 1 (SRCIN1) as a direct target gene of miR-510 in NSCLC. Expression of SRCIN1 was downregulated in lung cancer cells and negatively correlated with miR-510 expression in tumor tissues. Downregulation of SRCIN1, leading to inhibition of miR-510 expression, reversed cell proliferation and invasion in NSCLC cells. These results showed that miR-510 acted as an oncogenic miRNA in NSCLC, partly by targeting SRCIN1, suggesting that miR-510 can be a potential approach for the treatment of patients with malignant lung cancer.

Modulation of the IL-6-Signaling Pathway in Liver Cells by miRNAs Targeting gp130, JAK1, and/or STAT3

Interleukin-6 (IL-6)-type cytokines share the common receptor glycoprotein 130 (gp130), which activates a signaling cascade involving Janus kinases (JAKs) and signal transducer and activator of transcription (STAT) transcription factors. IL-6 and/or its signaling pathway is often deregulated in diseases, such as chronic liver diseases and cancer. Thus, the identification of compounds inhibiting this pathway is of interest for future targeted therapies. We established novel cellular screening systems based on a STAT-responsive reporter gene (Cypridina luciferase). Of a library containing 538 microRNA (miRNA) mimics, several miRNAs affected hyper-IL-6-induced luciferase activities. When focusing on candidate miRNAs specifically targeting 3′ UTRs of signaling molecules of this pathway, we identified, e.g., miR-3677-5p as a novel miRNA affecting protein expression of both STAT3 and JAK1, whereas miR-16-1-3p, miR-4473, and miR-520f-3p reduced gp130 surface expression. Interestingly, combination treatment with 2 or 3 miRNAs targeting gp130 or different signaling molecules of the pathway did not increase the inhibitory effects on phospho-STAT3 levels and STAT3 target gene expression compared to treatment with single mimics. Taken together, we identified a set of miRNAs of potential therapeutic value for cancer and inflammatory diseases, which directly target the expression of molecules within the IL-6-signaling pathway and can dampen inflammatory signal transduction.

miR-374a Inhibitor Enhances Etoposide-Induced Cytotoxicity Against Glioma Cells Through Upregulation of FOXO1

Glioma is a commonly diagnosed brain tumor that shows high mortality rate. Despite the great advancement of cancer therapy in recent years, chemotherapy is still an important approach for treatment of glioma. However, long-term chemotherapy usually causes serious side effects or complications. It is desirable to take strategies to enhance the efficacy of current chemotherapy. In the present study, we observed obvious upregulation of miR-374a in glioma cells. More importantly, we found that knockdown of miR-374a was able to enhance the etoposide-induced cytotoxicity against glioma cells. Mechanically, we demonstrated that FOXO1 was the target of miR-374a in glioma. Treatment with miR-374a inhibitor induced overexpression of FOXO1, and thus promoted the expression of Bim and Noxa. Since Bim and Noxa act as key proapoptotic proteins in mitochondrial apoptosis, miR-374a inhibitor was able to enhance the etoposide-induced apoptosis pathway in glioma.

A six-microRNA signature to predict outcomes of patients with gastric cancer

Gastric cancer (GC) is a common gastrointestinal tumor with poor prognosis. However, conventional prognostic factors cannot accurately predict the outcomes of GC patients. Therefore, there remains a need to identify novel predictive markers to improve prognosis. In this study, we obtained microRNA expression profiles of 385 GC patients from The Cancer Genome Atlas. We performed Cox regression analysis to identify overall survival‐related microRNA and then constructed a microRNA signature‐based prognostic model. The accuracy of the model was evaluated and validated through Kaplan–Meier survival analysis and time‐dependent receiver operating characteristic (ROC) curve analysis. The independent prognostic value of the model was assessed by multivariate Cox regression analysis. Enrichment analysis was performed to explore potential functions of the prognostic microRNA. Finally, a prognostic model based on a six‐microRNA (miRNA‐100, miRNA‐374a, miRNA‐509‐3, miRNA‐668, miRNA‐549, and miRNA‐653) signature was developed. Further analysis in the training, test, and complete The Cancer Genome Atlas set showed the model can distinguish between high‐risk and low‐risk patients and predict 3‐year and 5‐year survival. The six‐microRNA signature was also an independent prognostic marker, and enrichment analysis suggested that the microRNA may be involved in cell cycle and mitosis. These results demonstrated that the model based on the six‐microRNA signature can be used to accurately predict the prognosis of GC patients.

Downregulation of microRNA-374a predicts poor prognosis in human glioma

Certain microRNAs (miRNAs/miRs) may be used as prognostic biomarkers in various types of cancer. The purpose of the present study was to identify miRNAs that were abnormally expressed in glioma of different grades, and to evaluate their clinical implications in patients with glioma. The differentially expressed miRNAs were evaluated from the expression profiles of six glioma tissues (three low-grade and three high-grade gliomas) determined using a microarray platform. Reverse transcription-quantitative polymerase chain reaction analysis was used to further verify the aberrant expression of the candidate miRNA in a set of 42 patients and 5 healthy controls. The miRNA target genes were predicted and the protein-protein interaction network was generated; furthermore, functional enrichment analysis of the target genes in Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was performed. Kaplan-Meier curves and Log-rank analysis, as well as multivariate Cox regression analysis were performed to assess the association of the candidate miRNA with patient survival. A total of 15 differentially expressed miRNAs, including 13 downregulated and 2 upregulated miRNAs, were identified by comparison of low-grade and high-grade glioma tissues. The miR-374a expression of high-grade gliomas was significantly lower than that of low-grade gliomas (fold change, -4.43; P=0.027). The expression levels of miR-374a gradually decreased with the increase of the pathological grade of glioma. Pearson's Chi-square test was used to determine the association of miR-374a expression with several clinicopathological factors. Furthermore, low expression of miR-374a was determined to be an independent prognostic marker and that it was significantly associated with overall survival (P=0.0213). GO and KEGG pathway analysis revealed that the target genes of miR-374a may be involved in the regulation of the RNA polymerase II promoter and mTOR signaling pathway. The four hub genes (CCND1, SP1, CDK4, CDK6) were also identified by PPI network analysis. In conclusion, the present study indicated that miR-374a may be used as a promising prognostic biomarker for the screening of high-risk populations and for the assessment of the prognosis of patients with glioma.

Protective role of microRNA-374 against myocardial ischemia-reperfusion injury in mice following thoracic epidural anesthesia by downregulating dystrobrevin alpha-mediated Notch1 axis

Ischemia-reperfusion (I/R) injury often leads to myocardial apoptosis and necrosis. Studies have demonstrated the role microRNAs (miRs) played in myocardial I/R injury. Thus, we established a myocardial I/R injury model and a thoracic epidural anesthesia (TEA) model in mice to explore whether microRNA-374 (miR-374) affects myocardial I/R injury. We collected myocardial tissues to evaluate whether TEA exerts a protection effect on myocardial tissues. In addition, the levels of miR-374, dystrobrevin alpha (DTNA), and the statue of the Notch1 axis were detected. Subsequently, cardiomyocytes extracted from TEA mice were treated to regulate their levels of miR-374 and DTNA. After that, cell viability, cell cycle distribution, and apoptosis of cardiomyocytes were assessed. This was followed by the detection of the myocardial infarction area. The mice models of myocardial I/R injury were associated with poorly expressed miR-374 and highly expressed DTNA. TEA was found to protect myocardial tissues against myocardial I/R injury by elevating miR-374 and reducing DTNA. Dual-luciferase reporter assay validated that DTNA was the target gene of miR-374. Cardiomyocytes with overexpressed miR-374 were shown to have downregulated DTNA levels and blocked Notch1 axis. Overexpressed miR-374 was also found to promote the viability and inhibit the apoptosis of cardiomyocytes, as well as to increase the number of cells arrested in the S phase. In accordance with this, the myocardial infarction area was decreased with the upregulated miR-347 and downregulated DTNA. Collectively, these results demonstrated that, by inhibiting the activity of DTNA-mediated Notch1 axis, miR-374 could protect against myocardial I/R injury in mice after TEA.

miR-374a Regulates Inflammatory Response in Diabetic Nephropathy by Targeting MCP-1 Expression

The microRNA (mir)-374a has been implicated in several types of human cancer; however, its role in diabetic nephropathy (DN) remains unclear. Monocyte chemoattractant protein (MCP)-1 is a chemokine that recruits macrophages to inflammatory sites and is important for the development and progression of DN. However, the relationship between miR-374a and MCP-1 in DN is unknown. We addressed this in the present study by examining the expression of these factors in kidney tissue samples from DN patients and through loss- and gain-of-function experiments using HK2 human renal tubular epithelial cells. We found that miR-374a was downregulated whereas MCP-1 was upregulated in DN tissue. A bioinformatics analysis revealed that MCP-1 is a putative target of miR-374a. To confirm this relationship, HK2 cells treated with normal glucose (5.6 mmol/l D-glucose), high glucose (HG) (30 mmol/l D-glucose), or high osmotic pressure solution (5.6 mmol/l D-glucose + 24.4 mmol/l D-mannitol) were transfected with miR-374a mimic or inhibitor. miR-374a mimic reduced MCP-1 mRNA expression and migration of co-cultured U937 cells, whereas miR-374a inhibition had the opposite effects. Additionally, interleukin-6 and -18 and tumor necrosis factor-α levels were downregulated by transfection of miR-374a mimic. On the other hand, MCP-1 overexpression reversed the inhibitory effects of miR-374a in HK2 cells. Thus, miR-374a suppresses the inflammatory response in DN through negative regulation of MCP-1 expression. These findings suggest that therapeutic strategies that target the miR-374a/MCP-1 axis can be an effective treatment for DN.

Identification of recurrence-associated microRNAs in stage I lung adenocarcinoma

Lung cancer is the most common cause of cancer-associated death worldwide. Postoperative relapse and subsequent metastasis result in a high mortality rate, even in early stage lung cancer. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the post-transcriptional level and are frequently dysregulated in various cancers. The aim of this study was to identify recurrence-associated miRNAs in early stage lung cancer. To screen for differentially expressed miRNAs related to postoperative recurrence, miRNA microarray data derived from stage I lung adenocarcinoma formalin-fixed paraffin-embedded (FFPE) tissue samples (n = 6) and publically available the Cancer Genome Atlas (TCGA) data were analyzed. An independent sample (n = 29) was used to validate candidate miRNAs by quantitative real-time polymerase chain reaction (qRT-PCR). In miRNA expression profiling, we identified 60 significantly dysregulated miRNAs in the relapsed group. Additionally, 20 dysregulated miRNAs were found using TCGA data set. Three miRNAs (let-7g-5p, miR-143-3p, and miR-374a-5p) were associated with postoperative recurrence in both microarray and TCGA data sets. All 3 candidate miRNAs were validated in the independent cohort of stage I adenocarcinoma by qRT-PCR. We discovered 3 recurrence-associated miRNAs of stage I lung adenocarcinoma samples using FFPE tissue, which showed possible clinical utility as biomarkers predicting recurrence after curative surgery. Further investigation of the functional properties of these miRNAs is needed.

Upregulation of miR-374a promotes tumor metastasis and progression by downregulating LACTB and predicts unfavorable prognosis in breast cancer

Breast cancer (BRCA) is the second leading cause of cancer‐related death among female worldwide. Recent studies have revealed that LACTB was frequently repressed and functioned as a bona fide new tumor suppressor in a series of cancers, including BRCA. However, the molecular mechanisms underlying LACTB dysregulation in BRCA have not been reported. In the present study, we find that LACTB is repressed in BRCA and associated with poor prognosis by BRCA tissue microarray (TMA) analysis. Moreover, we confirm that LACTB is a direct target of miR‐374a, which is significantly overexpressed and associated with malignancies in BRCA. Mechanistically, applying loss‐of‐function and gain‐of‐function approaches in a series of in vitro and in vivo experiments show that miR‐374a knockdown suppresses the cell proliferative and colony formation activity, as well as migration and invasion capacity, but LACTB silencing in these cells reverses this change. Furthermore, we find that miR‐374a silencing markedly reduces the tumor growth in xenograft mouse models. In summary, our findings suggest the miR‐374a/LACTB axis plays a critical role in the tumorigenicity and progression of BRCA. miR‐374a/LACTB axis may be a potential target in the development of therapeutic strategies for BRCA patients.

Long-Term Cigarette Smoke Exposure and Changes in MiRNA Expression and Proteome in Non-Small-Cell Lung Cancer

Chronic exposure to cigarette smoke markedly increases the risk for lung cancer. Regulation of gene expression at the post-transcriptional level by miRNAs influences a variety of cancer-related interactomes. Yet, relatively little is known on the effects of long-term cigarette smoke exposure on miRNA expression and gene regulation. NCI-H292 (H292) is a cell line sensitive to cigarette smoke with mucoepidermoid characteristics in culture. We report, in this study, original observations on long-term (12 months) cigarette smoke effects in the H292 cell line, using microarray-based miRNA expression profiling, and stable isotopic labeling with amino acids in cell culture-based quantitative proteomic analysis. We identified 112 upregulated and 147 downregulated miRNAs (by twofold) in cigarette smoke-treated H292 cells. The liquid chromatography-tandem mass spectrometry analysis identified 3,959 proteins, of which, 303 proteins were overexpressed and 112 proteins downregulated (by twofold). We observed 39 miRNA target pairs (proven targets) that were differentially expressed in response to chronic cigarette smoke exposure. Gene ontology analysis of the target proteins revealed enrichment of proteins in biological processes driving metabolism, cell communication, and nucleic acid metabolism. Pathway analysis revealed the enrichment of phagosome maturation, antigen presentation pathway, nuclear factor erythroid 2-related factor 2-mediated oxidative stress response, and cholesterol biosynthesis pathways in cigarette smoke-exposed cells. In conclusion, this report makes an important contribution to knowledge on molecular changes in a lung cell line in response to long term cigarette smoke exposure. The findings might inform future strategies for drug target, biomarker and diagnostics innovation in lung cancer, and clinical oncology. These observations also call for further research on the extent to which continuing or stopping cigarette smoking in patients diagnosed with lung cancer translates into molecular and clinical outcomes.

A 10‑microRNA prognosis scoring system in esophageal squamous cell carcinoma constructed using bioinformatic methods

MicroRNA (miR) signatures may aid the diagnosis and prediction of cancer; therefore, miRs associated with the prognosis of esophageal squamous cell carcinoma (ESCC) were screened. miR‑sequencing (seq) and mRNA‑seq data from early‑stage ESCC samples were downloaded from The Cancer Genome Atlas (TCGA) database, and samples from subjects with a >6‑month survival time were assessed with Cox regression analysis for prognosis‑associated miRs. A further two miR expression datasets of ESCC samples, GSE43732 and GSE13937, were downloaded from the Gene Expression Omnibus database. Common miRs between prognosis‑associated miRs, and miRs in the GSE43732 and GSE13937, datasets were used for risk score calculations for each sample, and median risk scores were applied for the stratification of low‑ and high‑risk samples. A prognostic scoring system of signature miRs was subsequently constructed and used for survival analysis for low‑ and high‑risk samples. Differentially‑expressed genes (DEGs) corresponding to all miRs were screened and functional annotation was performed. A total of 34 prognostic miRs were screened and a scoring system was created using 10 signature miRs (hsa‑miR‑140, ‑33b, ‑34b, ‑144, ‑486, ‑214, ‑129‑2, ‑374a and ‑412). Using this system, low‑risk samples were identified to be associated with longer survival compared with high‑risk samples in the TCGA and GSE43732 datasets. Age, alcohol and tobacco use, and radiotherapy were prognostic factors for samples with different risk scores and the same clinical features. There were 168 DEGs, and the top 20 risk scores positively‑correlated and the top 20 risk scores negatively‑correlated DEGs were significantly enriched for six and 10 functional terms, respectively. 'Tight junction' and 'melanogenesis' were two significantly enriched pathways of DEGs. miR‑214, miR‑129‑2, miR‑37a and miR‑486 may predict ESCC patient survival, although further studies to validate this hypothesis are required.

Dual roles of miR-374a by modulated c-Jun respectively targets CCND1-inducing PI3K/AKT signal and PTEN-suppressing Wnt/β-catenin signaling in non-small-cell lung cancer

MiR-374a appears to play a complex role in non-small-cell lung cancer (NSCLC). Here, we demonstrate a dual role for miR-374a in NSCLC pathogenesis. The effects and modulatory mechanisms of miR-374a on cell growth, migration, invasion, and in vivo tumorigenesis and metastasis in nude mice were also analyzed. The expression of miR-374a was examined in NSCLC and non-cancerous lung tissues by quantitative real-time reverse transcription-PCR (qRT-PCR), and in situ hybridization, respectively. miR-374a directly targets CCND1 and inactivates PI3K/AKT and Ras-mediated cell cycle signalings, as well as epithelial–mesenchymal transition (EMT). This not only dramatically suppressed cell growth, migration, invasion,and metastasis, but also elevated A549 and pc-9 NSCLC cell sensitivity to cisplatin (DDP) while increasing survival time of tumor-bearing mice. Interestingly, miR-374a serves an inverse function in SPCA-1 and H1975 NSCLC cells by directly targeting PTEN to activate Wnt/β-catenin and Ras signalings and its downstream cascade signals. Surprisingly, transcription factor c-Jun bound to the promoter region of human miR-374a and suppressed miR-374a in A549 and pc-9 cells while inducing it in SPCA-1 and H1975 cells. Increased levels of miR-374a appeared to serve a protective role by targeting CCND1 in early-stage NSCLC (Stages I and II). Inversely, increased miR-374a was an unfavorable factor when targeting PTEN in more advanced staged NSCLC patients. Our studies are the first to demonstrate that miR-374a plays divergent roles in NSCLC pathogenesis at different stages of the disease and implicate the potential application of miR-374a targeting for cancer therapy.

microRNA-374a suppresses colon cancer progression by directly reducing CCND1 to inactivate the PI3K/AKT pathway

microRNA-374a (miR-374a) exhibits oncogenic functions in various tumor types. Here we report that miR-374a suppresses proliferation, invasion, migration and intrahepatic metastasis in colon adenocarcinoma cell lines HCT116 and SW620. Notably, we detected that PI3K/AKT signaling and its downstream cell cycle factors including c-Myc, cyclin D1 (CCND1), CDK4 and epithelial-mesenchymal transition (EMT)-related genes including ZEB1, N-cadherin, Vimentin, Slug, and Snail were all significantly downregulated after miR-374a overexpression. Conversely, cell cycle inhibitors p21 and p27 were upregulated. Expression of E-cadherin was only decreased in HCT116, without any obvious differences observed in SW620 cells. Furthermore, luciferase reporter assays confirmed that miR-374a could directly reduce CCND1. Interestingly, when CCND1 was silenced or overexpressed, levels of pPI3K, pAkt as well as cell cycle and EMT genes were respectively downregulated or upregulated. We examined miR-374a levels by in situ hybridization and its correlation with CCND1 expression in CRC tumor tissues. High miR-374a expression with low level of CCND1 was protective factor in CRC. Together these findings indicate that miR-374a inactivates the PI3K/AKT axis by inhibiting CCND1, suppressing of colon cancer progression.

MicroRNAs miR-19, miR-340, miR-374 and miR-542 regulate MID1 protein expression

The MID1 ubiquitin ligase activates mTOR signaling and regulates mRNA translation. Misregulation of MID1 expression is associated with various diseases including midline malformation syndromes, cancer and neurodegenerative diseases. While this indicates that MID1 expression must be tightly regulated to prevent disease states specific mechanisms involved have not been identified. We examined miRNAs to determine mechanisms that regulate MID1 expression. MicroRNAs (miRNA) are small non-coding RNAs that recognize specific sequences in their target mRNAs. Upon binding, miRNAs typically downregulate expression of these targets. Here, we identified four miRNAs, miR-19, miR-340, miR-374 and miR-542 that bind to the 3'-UTR of the MID1 mRNA. These miRNAs not only regulate MID1 expression but also mTOR signaling and translation of disease associated mRNAs and could therefore serve as potential drugs for future therapy development.

Protective Effect of miR-374a on Chemical Hypoxia-Induced Damage of PC12 Cells In Vitro via the GADD45α/JNK Signaling Pathway

To explore the effect of microRNA-374a (miR-374a) on chemical hypoxia-induced pheochromocytoma (PC12) cell damage by mediating growth arrest and the DNA damage-45 alpha (GADD45α)/c-Jun N-terminal kinase (JNK) signaling pathway. PC12 cells were divided into a Control group (no treatment), Model group (treated with CoCl₂ for 24 h), negative control (NC) group (transfected with miR-374a negative control sequence and treated with CoCl₂ for 24 h), and miR-374a mimic group (transfected with miR-374a mimics and treated with CoCl₂ for 24 h). The viability and apoptosis of PC12 cells were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, while the mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) content were assessed by Rh123 and dichloro-dihydro-fluorescein diacetate (DCFH-DA) methods. The expression of miR-374a and GADD45α/JNK proteins was detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. A significant decrease was found in the survival rate, MMP and miR-374a expression, while an increase was shown in the ROS content and GADD45α and p-JNK expression in hypoxic PC12 cells (all P < 0.05). A luciferase reporter gene assay demonstrated that GADD45α is the target gene of miR-374a. When transfected with miR-374a mimics, hypoxic PC12 cells showed an obvious elevation in survival rate and MMP but a great reduction in cell apoptosis and ROS content, as well as in the expression of GADD45α and p-JNK proteins (all P < 0.05). MiR-374a can protect PC12 cells against hypoxia-induced injury by inhibiting the GADD45α/JNK pathway, enhancing cell viability, suppressing oxidative stress, and inhibiting cell apoptosis, thereby becoming a potential therapeutic target for hypoxic damage.

Isoliquiritigenin modulates miR-374a/PTEN/Akt axis to suppress breast cancer tumorigenesis and metastasis

Breast cancer is one of the most frightful causes of death among females worldwide. Accumulating evidence attached the importance of microRNAs negative regulation to tumorigenesis in breast cancer, suggesting novel cancer therapies targeting microRNAs modulation. Recent studies demonstrated that isoliquiritigenin could inhibit breast cancer cells proliferation and migration, but the underlying mechanism is still limited. In this study, the anti-cancer effects as well as the detailed mechanisms of isoliquiritigenin were explored. The results proved that isoliquiritigenin could negatively regulate breast cancer growth through the induction of apoptosis. We also verified the anti-cancer effect of isoliquiritigenin on migration and invasion, and identified highly expressed miR-374a as one of the main microRNAs down-regulated by isoliquiritigenin treatment in breast cancer. Further study displayed that isoliquiritigenin increased PTEN expression through the decrease of miR-374a expression to inhibit the aberrant Akt signaling. Our findings suggest isoliquiritigenin as a novel anti-cancer candidate significantly regulating miR-374a/PTEN/Akt axis in microRNA-based breast cancer therapies.

MicroRNA-374a Promotes Hepatocellular Carcinoma Cell Proliferation by Targeting Mitogen-Inducible Gene 6 (MIG-6)

Hepatocellular carcinoma (HCC) is a disease with poor prognosis rates and ineffective therapeutic options. Previous studies have reported the involvement of mitogen-inducible gene 6 (MIG-6) as a negative regulator in tumor formation. MicroRNAs (miRNAs) play crucial roles in the development of different types of cancer. However, the underlying mechanisms of miRNAs in HCC are poorly understood. This study was aimed to investigate the role of miR-374a in HCC and its role in the regulation of expression of MIG-6. The results showed that MIG-6 overexpression significantly inhibited cell viability of HepG2 cells after 4 days posttransfection. Moreover, MIG-6 was a direct target of miR-374a, and the expression of MIG-6 was remarkably downregulated by the overexpression of miR-374a in HepG2 cells. Furthermore, we found that overexpression of miR-374a promoted cell viability; however, the protective effect was abolished by MIG-6 overexpression. In addition, overexpression of miR-374a activated the EGFR and AKT/ERK signaling pathways by regulation of MIG-6. Our findings suggest that miR-374a could promote cell viability by targeting MIG-6 and activating the EGFR and AKT/ERK signaling pathways. These data provide a promising therapeutic strategy for HCC treatment.

miR-374 mediates the malignant transformation of gastric cancer-associated mesenchymal stem cells in an experimental rat model

Mesenchymal stem cells (MSCs) are a critical component of the tumor microenvironment. Upon distinct pathological stimulus, MSCs show phenotypic and functional changes. Gastric cancer is one of the leading causes of cancer‑related deaths worldwide. The roles and mechanisms of MSCs in gastric cancer have not been well characterized. In the present study, we investigated the roles of MSCs in the malignant transformation from gastritis to gastric cancer using an N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced gastric cancer model. We isolated MSCs from the gastric tissues of normal (RGN-MSCs) and MNNG-exposed rats (RGI-MSCs), and compared the biological properties of RGI-MSCs with RGN-MSCs. We found that RGI-MSCs had increased proliferative and migratory capabilities than these capacities noted in the RGN-MSCs. In addition, RGI-MSCs produced higher levels of IL-6, CXCL10 and MCP-1 than RGN-MSCs. Moreover, RGI-MSCs promoted the migration of normal gastric mucosa epithelial cells by inducing epithelial-mesenchymal transition (EMT). The upregulation of miR-374 in RGI-MSCs was partially responsible for their increased proliferative and migratory capabilities. Collectively, our findings provide new evidence for the roles of MSCs in gastric carcinogenesis, suggesting that targeting gastric cancer-associated MSCs may represent a novel avenue for gastric cancer therapy.

MiR-451 as a new tumor marker for gastric cancer

Gastric cancer is the second most common malignancy in China. However, the prognosis for gastric cancer patients remains poor. The purpose of this study was to investigate whether miR-451 was a potential prognostic biomarker for gastric cancer. Fresh tissues were immediately frozen in liquid nitrogen until use. The plasma was extracted and quantitative real-time polymerase chain reaction was performed to detect miR-451 expression. The Student's t test analysis and multivariate Cox regression analysis were performed to analyze expression of miR-451. The analysis results showed that the expression level of miR-451 was decreased expression in gastric cancer tissue. The down-regulation of miR-451 tended to be positively correlated with tumor stage, lymphatic metastasis and shorter overall survival of patients. MiR-451 may be a potential biomarker and a potential therapeutic target for the diagnoses and prognosis of gastric cancer.

PTIP promotes recurrence and metastasis of hepatocellular carcinoma by regulating epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) is one of the most lethal tumors worldwide, which is mainly due to the high recurrence and metastasis rate after hepatectomy. In this study, we found that PTIP expression was dramatically upregulated in human HCC tissues and cell lines. High expression of PTIP was shown to be associated with aggressive clinicopathological features, including liver cirrhosis, vascular invasion and advanced stage. In addition, PTIP overexpression was independently associated with shorter survival and increased HCC recurrence in patients. Knockdown of the PTIP expression significantly inhibited invasion and metastasis in vitro and in vivo, whereas ectopic expression of PTIP significantly promoted invasion and metastasis. Mechanistically, PTIP promotes HCC progress by facilitating epithelial-mesenchymal transition (EMT). Notably, we also found that PTIP might increase miR-374a expression to promote EMT and metastasis in HCC. In summary, our study identified PTIP as a new potential prognostic indicator and therapeutic target for HCC.

The scaffold protein p140Cap limits ERBB2-mediated breast cancer progression interfering with Rac GTPase-controlled circuitries

The docking protein p140Cap negatively regulates tumour cell features. Its relevance on breast cancer patient survival, as well as its ability to counteract relevant cancer signalling pathways, are not fully understood. Here we report that in patients with ERBB2-amplified breast cancer, a p140Cap-positive status associates with a significantly lower probability of developing a distant event, and a clear difference in survival. p140Cap dampens ERBB2-positive tumour cell progression, impairing tumour onset and growth in the NeuT mouse model, and counteracting epithelial mesenchymal transition, resulting in decreased metastasis formation. One major mechanism is the ability of p140Cap to interfere with ERBB2-dependent activation of Rac GTPase-controlled circuitries. Our findings point to a specific role of p140Cap in curbing the aggressiveness of ERBB2-amplified breast cancers and suggest that, due to its ability to impinge on specific molecular pathways, p140Cap may represent a predictive biomarker of response to targeted anti-ERBB2 therapies.

p140Cap adaptor proteins interfere with adhesion and growth factor-dependent signalling in cancer cells but the mechanisms are unclear. Here the authors show that p140Cap interferes with ERBB2-dependent activation of Rac GTPase-controlled circuitries reducing metastasis and cancer progression.