miR-125a-3p targets MTA1 to suppress NSCLC cell proliferation, migration, and invasion

miR-125a-3p regulates apoptosis by suppressing TMBIM4 in lens epithelial cells

PURPOSE

To explore the regulatory effect of miR-125a-3p on lens epithelial cells (LECs) under ultraviolet radiation B (UVB) irradiation.

METHODS

The expression of miR-125a-3p in age-related cataract (ARC) specimens and cell models was detected by qRT-PCR. UVB was utilized to establish DNA damage model of LECs. Cell count kit-8 was applied in detecting cell viability. Cell apoptosis ratio was analyzed by flow cytometry. Dual luciferase reports were applied to analyze the mechanism between miRNA and target genes. Nanoparticle tracking analysis, and Western blot were used to identify whether the exosomes were typical exosomes.

RESULTS

miR-125a-3p was upregulated in ARC tissues and LECs treated with UVB. Knockdown of miR-125a-3p in LECs significantly decreased apoptosis and increased viability of UVB-irradiated LECs. We predicted that miR-125a-3p could regulate transmembrane Bax inhibitor motif containing 4 (TMBIM4) by the bioinformatics databases TargetScan, miRBase, and miRWalk. Luciferase reporter assays demonstrated that miR-125a-3p may suppress TMBIM4 protein translation by binding to 3'UTR of TMBIM4 mRNA. Overexpression of miR-125a-3p decreased TMBIM4, which suggested that miR-125a-3p could inhibit TMBIM4. Moreover, knockdown of TMBIM4 decreased cell viability and enhanced cell apoptosis during UVB irradiation. In addition, the exosome secretion of LECs irradiated by UVB was enhanced, and the expression of miR-125a-3p was high. Cell viability was significantly decreased, and cell apoptosis was increased during UVB-exos treatment.

CONCLUSION

This study indicated that miR-125a-3p regulated apoptosis by suppressing TMBIM4 in LECs under oxidative damage, providing a new idea for clinical therapeutic target of cataract.

Polyphenols as Lung Cancer Chemopreventive Agents by Targeting microRNAs

Lung cancer is the second leading cause of cancer-related death worldwide. In recent decades, investigators have found that microRNAs, a group of non-coding RNAs, are abnormally expressed in lung cancer, and play important roles in the initiation and progression of lung cancer. These microRNAs have been used as biomarkers and potential therapeutic targets of lung cancer. Polyphenols are natural and bioactive chemicals that are synthesized by plants, and have promising anticancer effects against several kinds of cancer, including lung cancer. Recent studies identified that polyphenols exert their anticancer effects by regulating the expression levels of microRNAs in lung cancer. Targeting microRNAs using polyphenols may provide a novel strategy for the prevention and treatment of lung cancer. In this review, we reviewed the effects of polyphenols on oncogenic and tumor-suppressive microRNAs in lung cancer. We also reviewed and discussed the potential clinical application of polyphenol-regulated microRNAs in lung cancer treatment.

LncRNA TP73-AS1 Exacerbates the Non-Small-Cell Lung Cancer (NSCLC) Process via Regulating miR-125a-3p-Mediated ACTN4

Background

LncRNA TP73-AS1 has been revealed to exert a noteworthy impact on the occurrence and advancement of different cancers. In this study, we explored the function of TP73-AS1 in tumor growth, cell progression as well as the relevant molecular mechanism in non-small-cell lung cancer (NSCLC).

Methods

QRT-PCR was employed to assess the expression of TP73-AS1, miR‐125a-3p, and actinin alpha 4 (ACTN4) in NSCLC cells. The biological effect of TP73-AS1 on NSCLC cells was assessed by cell transfection, CCK8, and transwell experiments. We further predicted the interaction among RNAs (TP73-AS1, miR-125a-3p, and ACTN4) through bioinformatics online tools and verified via luciferase reporter, RNA immunoprecipitation, and qRT-PCR assays. Xenograft models of SPC-A1 cells were conducted to test how TP73-AS1 regulates tumorigenesis. Western blot, as well as the immunohistochemistry (IHC) assays, was utilized to measure the expression levels. Functions of TP73-AS1 in NSCLC progression through the miR-125a-3p/ACTN4 axis were investigated by rescue experiments.

Results

Knockdown of TP73-AS1 suppressed the growth and simultaneously attenuated the migration and invasion ability of NSCLC SPC-A1 and A549 cells. Bioinformatics and molecular mechanism assays demonstrated that TP73-AS1 could bind to miR-125a-3p/ACTN4 and regulate their expression. Moreover, the rescued‐function experiment demonstrated that suppressing miR-125a-3p or elevating ACTN4 turned around the suppression effect of sh-TP73-AS1 on NSCLC progression. TP73-AS1 inhibition could also inhibit the NSCLC tumor growth and correspondingly regulated the expression of miR-125a-3p and ACTN4 in the tumor xenograft model.

Conclusion

The present study indicated that TP73-AS1 affects NSCLC progression through a new competitive RNA (ceRNA) regulatory network of miR-125a-3p/ACTN4, providing an underlying target for NSCLC treatment in the future.

Circular RNA hsa_circ_0002483 promotes growth and invasion of lung adenocarcinoma by sponging miR-125a-3p

Background

Increasing evidence indicates that the aberrant expression of circular RNAs (circRNAs) is involved in the pathogenesis and progression of lung adenocarcinoma (LUAC). However, the function and molecular mechanisms of hsa_circ_0002483 (circ_0002483) in LUAC remain unclear.

Methods

The association between circ_0002483 expression and clinicopathological characteristics and prognosis in patients with LUAC was analyzed by fluorescence in situ hybridization. The functional experiments such as CCK-8, colony formation and Transwell assays and a subcutaneous tumor model were conducted to determine the role of circ_0002483 in LUAC cells. The specific binding between circ_0002483 and miR-125a-3p was validated by RNA immunoprecipitation, luciferase gene report and qRT-PCR assays. The effects of circ_0002483 on miR-125a-3p-mediated C-C motif chemokine ligand 4 (CCL4)-CCR5 axis were assessed by Western blot analysis.

Results

We found that circ_0002483 was upregulated in LUAC tissue samples and associated with Tumor Node Metastasis (TNM) stage and poor survival in patients with LUAC. Knockdown of circ_0002483 inhibited proliferation, colony formation and invasion of A549 and PC9 cells in vitro, whereas overexpression of circ_0002483 harbored the opposite effects. Furthermore, circ_0002483 sponged miR-125a-3p and negatively regulated its expression. CCL4 was identified as a direct target of miR-125a-3p. The rescue experiments showed that miR-125a-3p mimics reversed the tumor-promoting effects of circ_0002483 by targeting CCL4-CCR5 axis in A549 and PC9 cells. In addition, the in vivo experiment further validated that knockdown of circ_0002483 repressed tumor growth.

Conclusions

Our findings demonstrated that circ_0002483 could act as a sponge of miR-125a-3p to upregulate CCL4-CCR5 axis, contributing to the tumorigenesis of LUAC, and represent a potential therapeutic target for LUAC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02241-y.

TMT-based proteomics analysis of the effects of Qianjinweijing Tang on lung cancer

Qianjinweijing Tang (QJWJ) is a classic traditional Chinese formula that is often used in the treatment of treat lung cancer (LC). However, the underlying cellular mechanisms of the anticancer effects of QJWJ remain unclear. Cell viability was determined by MTS assay and levels of apoptosis measured by flow cytometry. Animal experiments were conducted to determine the effects of QJWJ on tumor growth in vivo. We used a proteomics approach to study the effects of QJWJ on LC cells and applied bioinformatics analysis to identify differentially expressed proteins that were validated by western blotting. QJWJ inhibited the proliferation of LC cells and induced apoptosis. The tumor growth delay effects of QJWJ were confirmed in vivo. We identified 104 differentially expressed proteins following QJWJ treatments of which 45 proteins were upregulated and 59 were downregulated. The levels of differentially expressed proteins were validated by western blotting. Our study indicated that QJWJ has anticancer effects in vivo and in vitro and that these effects are mediated by modulating the expression of tumor-related proteins.

LncRNA HOTAIRM1 knockdown inhibits cell glycolysis metabolism and tumor progression by miR-498/ABCE1 axis in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is a major contributor of cancer-related mortality. Long non-coding RNAs (lncRNAs) are indicated to participate in the pathogenesis of NSCLC.

OBJECTIVE

In this research, the effects of lncRNA HOXA transcript antisense RNA, myeloid-specific 1 (HOTAIRM1) on NSCLC progression and underlying mechanism were revealed.

METHODS

The expression levels of HOTAIRM1 and microRNA-498 (miR-498) were detected by quantitative real time polymerase chain reaction (qRT-PCR) in NSCLC tissues, cells or exosomes. The protein expression of CD63, CD81, hexokinase 2 (HK2) and ATP binding cassette subfamily E member 1 (ABCE1) was determined by western blot. Cell viability, apoptosis, migration and invasion were investigated by cell counting kit-8 (CCK-8), flow cytometry, transwell migration and invasion assays, respectively. Cell glycolysis metabolism was revealed by glucose uptake and lactate production assays and western blot analysis. The binding relationship between miR-498 and HOTAIRM1 or ABCE1 was predicted by DIANA-LncBase v2 and starBase online database, and identified by dual-luciferase reporter assay. The effects of HOTAIRM1 on NSCLC growth in vivo were revealed by in vivo tumor formation assay.

RESULTS

HOTAIRM1 expression was dramatically upregulated, whereas miR-498 expression was significantly downregulated in NSCLC tissues cells or exosomes as compared to control groups. Mechanistically, HOTAIRM1 knockdown repressed cell viability, migration, invasion and glycolysis metabolism, whereas induced cell apoptosis in NSCLC; however, miR-498 inhibitor hindered these effects. Functionally, HOTAIRM1 functioned as a sponge of miR-498 and miR-498 targeted ABCE1. In addition, HOTAIRM1 silencing inhibited NSCLC growth in vivo by downregulating ABCE1 and upregulating miR-498 expression.

CONCLUSIONS

HOTAIRM1 knockdown repressed cell glycolysis metabolism and tumor development by reducing ABCE1 expression through sponging miR-498 in NSCLC, which provided a theoretical basis for further studying NSCLC progression.

MicroRNA-125a-3p overexpression promotes liver regeneration through targeting proline-rich acidic protein 1

INTRODUCTION AND OBJECTIVES

Liver regeneration plays a valuable significance for hepatectomies, and is mainly attributed to hepatocyte proliferation. MicroRNA-125a-3p was reported to be highly associated with liver regeneration process. We studied the underlying mechanism of the functional role of miR-125a-3p in liver regeneration.

MATERIALS AND METHODS

The miR-125a-3p mimics and inhibitor vector were constructed and transfected into primary human liver HL-7702 cells, the transfected cell viability was detected using cell counting kit-8 (CCK-8). Cell cycle distribution was analyzed by flow cytometry. With Targetscan and OUGene prediction, the potential targets of miR-125 were verified by real-time quantitative PCR (qPCR) and luciferase reporter assays in turn. The overexpression vector of proline-rich acidic protein 1 (PRAP1) was constructed and co-transfected with miR-125a-3p mimics into HL-7702 cells, detecting the changes of proliferative capacity and cell cycle distribution. Western blot and qPCR performed to analyze gene expressions.

RESULTS

Overexpressed miR-125a-3p notably increased the hepatocyte viability at 48h, and decreased the number of G1 phase cells (p<0.05). However, miR-125a-3p inhibition suppressed the development of hepatocytes. PRAP1 was the target of miR-125a-3p. After co-transfection with PRAP1 vector, hepatocyte viability was decrease and the G1 phase cell number was increased (p<0.05). More importantly, overexpressed PRAP1 notably decreased the mRNA and protein levels of cyclin D1, cyclin-dependent kinase 2 (CDK2) and cell division cycle 25A (CDC25A).

CONCLUSION

The elevated miR-125a-3p positively correlated with hepatocyte viability and cell cycle progression due to the modulation of PRAP1, and miR-125a-3p may contribute to improving liver regeneration.

MiR-543 promotes tumorigenesis and angiogenesis in non-small cell lung cancer via modulating metastasis associated protein 1

OBJECTIVE

This study is aimed to explore the role of miR-543 in non-small cell lung cancer (NSCLC), and verify whether miR-543 targets metastasis associated protein 1 (MTA1) to affect tumorigenesis and angiogenesis in NSCLC.

METHODS

Firstly, miR-543 mimic and inhibitor were transfected into A549 cells and H1299 cells. The cells proliferation was tested by MTT and clone formation. The cells apoptosis was analyzed by cytometry. Tube formation assay was used to measure the vascularization of cells. qRT-PCR and Western Blot were used to measure the MTA1 expression. Dual-luciferase assay was used to analyze whether miR-543 targets MTA1. Secondly, MTA1 mimic and inhibitor were transfected into cells to analyze the effect of MTA1 on proliferation and angiogenesis in NSCLC cells. Lastly, the nude mice were used to verify the effect of miR-543 on tumorigenesis and angiogeneisis in NSCLC via modulating MATA1.

RESULTS

miR-543 overexpression could apparently promote cells proliferation and angiogeneisis in NSCLC cells. Meanwhile, the MTA1 expression was increased after transfecting miR-543 mimic. Dual luciferase reporter assay revealed MTA1 was a downstream target of miR-543. Further studies showed that inhibition of MTA1 weakened the role of miR-543 overexpression in NSCLC cells. Vivo experiments revealed that miR-543 promoted cells proliferation and angiogenesis in tumor tissues via modulating MTA1.

CONCLUSION

miR-543 could target MTA1 to promote tumorigenesis and angiogenesis in NSCLC via targeting MTA1.

The permissive role of TCTP in PM2.5/NNK-induced epithelial-mesenchymal transition in lung cells

Background

Translationally controlled tumor protein (TCTP) is linked to lung cancer. However, upon lung cancer carcinogens stimulation, there were no reports on the relationship between TCTP and lung cell carcinogenic epithelial–mesenchymal transition (EMT). This study was designed to investigate the molecular mechanism of regulation of TCTP expression and its role in lung carcinogens-induced EMT.

Methods

To study the role of TCTP in lung carcinogens [particulate matter 2.5 (PM_2.5) or 4-methylnitrosamino-l-3-pyridyl-butanone (NNK)]-induced EMT, PM_2.5/NNK-treated lung epithelial and non-small cell lung cancer (NSCLC) cells were tested. Cell derived xenografts, human lung cancer samples and online survival analysis were used to confirm the results. MassArray assay, Real-time PCR and Reporter assays were performed to elucidate the mechanism of regulation of TCTP expression. All statistical analyses were performed using GraphPad Prism version 6.0 or SPSS version 20.0.

Results

Translationally controlled tumor protein and vimentin expression were up-regulated in PM_2.5/NNK-treated lung cells and orthotopic implantation tumors. TCTP expression was positively correlated with vimentin in human NSCLC samples. Patients with high expression of TCTP displayed reduced overall and disease-free survival. TCTP overexpression could increase vimentin expression and promote cell metastasis. Furthermore, PM_2.5/NNK stimulation brought a synergistic effect on EMT in TCTP-transfected cells. TCTP knockdown blocked PM_2.5/NNK carcinogenic effect. Mechanically, PM_2.5/NNK-induced TCTP expression was regulated by one microRNA, namely miR-125a-3p, but not by methylation on TCTP gene promoter. The level of TCTP was regulated by its specific microRNA during the process of PM_2.5/NNK stimulation, which in turn enhanced vimentin expression and played a permissive role in carcinogenic EMT.

Conclusions

Our results provided new insights into the mechanisms of TCTP regulatory expression in lung carcinogens-induced EMT. TCTP and miR-125a-3p might act as potential prognostic biomarkers and therapeutic targets for NSCLC.

miR-125a-3p suppresses the growth and progression of papillary thyroid carcinoma cell by targeting MMP11

The dysregulation of miR-125a-3p has been observed in multiple tumor types. Nevertheless, the function of miR-125a-3p in papillary thyroid carcinoma (PTC) is yet to be explored. Herein, we find that miR-125a-3p is markedly downregulated in PTC tissues, and its level is inversely related to the histological grade of PTC. Upregulation of miR-125a-3p suppresses the pulmonary metastatic ability as well as the tumor growth of PTC cell in vivo. Consistently, the colony formation ability and other metastasis-related traits of PTC cell are inhibited by miR-125a-3p transfection in vitro. In addition, we identify that matrix metalloprotease 11 (MMP11) is the direct target gene of miR-125a-3p, and that miR-125a-3p inhibits cell viability, migration, and invasiveness of PTC cell by reducing MMP11 expression in vitro. Together, these data testify that the miR-125a-3p/MMP11 axis plays vital roles in the growth and progression of human PTC cells.

Dexamethasone and lenvatinib inhibit migration and invasion of non-small cell lung cancer by regulating EKR/AKT and VEGF signal pathways

Migration and invasion is one of the most important features in tumor metastasis and development. Non-small cell lung cancer (NSCLC) is one of the most common types of cancer globally, and has been linked to air contamination. Evidence indicates that cysteine-rich angiogenic inducer 61 (CYR61) is associated with the migration and invasion of NSCLC. Overexpression of CYR61 protein promotes the migration and the transition of tumor-derived vascular endothelial cells in NSCLC. However, the association between CYR61 and NSCLC remains poorly understood. Lenvatinib is an oral multi-target drug that targets various receptors upon tumor angiogenesis. Dexamethasone is widely approved for combination therapy in patients with NSCLC. In the current study, the expression and function of CYR61 in NSCLC was analyzed during the progression of NSCLC. Inhibitory effects on migration and invasion induced by lenvatinib and dexamethasone were determined by migratory and invasion assays. Migratory pathways of extracellular signal-regulated kinases (ERK) and protein kinase B (AKT) were also investigated by targeting vascular endothelial growth factor (VEGF) and CYR61 via synergistic treatment with transforming growth factor-β1 (TGF-β1) and dexamethasone. Therapeutic outcomes of combined treatment with lenvatinib and dexamethasone were assessed in NSCLC-bearing mice. The results of the present study indicate that cooperative treatment of lenvatinib and dexamethasone significantly inhibited TGF-β1-induced cell migration and suppressed tumor growth (P<0.01). Notably, the results demonstrated that dexamethasone eradicated the promotion effects of TGF-β1 on the AKT/epithelial-mesenchymal transition process and lenvatinib extinguished tumor cell metastasis by targeting VEGF. The results of the current study also demonstrate that dexamethasone suppressed the expression of CAG-I and enhanced expression of matrix metalloproteinase-1. Synergistic treatment for NSCLC was demonstrated to be efficacious. In conclusion, dexamethasone inhibited AKT/ERK phosphorylation and lenvatinib antagonism bound VEGF leading to the limitation of migration and invasion of cancer cells in NSCLC.

Downregulated Expression of hsa_circ_0005556 in Gastric Cancer and Its Clinical Significance

Background

Gastric cancer (GC) has a poor prognosis due to the lack of ideal tumor markers. Circular RNAs (circRNAs) are a novel type of noncoding RNA related to the occurrence of GC. Among our research, we investigated the role of hsa_circ_0005556 in GC.

Materials and Methods

The expression of hsa_circ_0005556 of 100 paired GC tissues and adjacent normal tissues was detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). A receiver operating characteristic (ROC) curve was established to evaluate the diagnostic value of hsa_circ_0005556. The correlation between the expression of hsa_circ_0005556 and corresponding clinicopathological characteristic was explored.

Results

hsa_circ_0005556 was significantly downregulated in GC tissues contrasted with adjacent normal tissues (n = 100, p < 0.001). The areas under the ROC curve (AUC) of hsa_circ_0005556 were up to 0.773, while 64% sensitivity and 82% specificity, respectively. Moreover, its expression levels were significantly associated with differentiation (p = 0.001), TNM stage (p = 0.013), and lymphatic metastasis (p = 0.039). GC patients of high hsa_circ_0005556 levels had a longer overall survival (OS) than those of the low group (p = 0.047).

Conclusion

hsa_circ_0005556 is a potential biomarker for GC, which may guide judgment of the indication of endoscopic treatment for early gastric cancer (EGC).

MicroRNA-125a-3p affects smooth muscle cell function in vascular stenosis

AIMS

Many studies have indicated that microRNAs are closely related to the process of peripheral arterial disease (PAD). Previously, we found that microRNA-125a-3p (miR-125a-3p) in restenotic arteries after interventional therapy of lower extremity vessels was notably decreased compared with that of normal control arteries. However, its role in the development of vascular stenosis is not yet clearly understood. The purpose of this study was to investigate the expression, regulatory mechanism and function of miR-125a-3p in the process of vascular stenosis.

METHODS AND RESULTS

Quantitative reverse-transcription polymerase chain reaction assays indicated that miR-125a-3p in restenotic arteries after interventional therapy was significantly lower than that in normal control arteries. Immunofluorescence and in situ hybridization co-staining assays in arterial sections demonstrated that miR-125a-3p was mainly expressed in the medial smooth muscle layer. Transfection of miR-125a-3p mimics into cultured vascular smooth muscle cells (VSMCs) effectively inhibited cell proliferation and migration. Then, western blot and luciferase activity assays showed that recombinant human mitogen-activated protein kinase 1 (MAPK1) was a functional target of miR-125a-3p and was involved in miR-125a-3p-mediated cell effects. Finally, the lentiviral infection of miR-125a-3p in balloon-injured rat carotid vascular walls showed that miR-125a-3p overexpression significantly reduced the probability of neointimal membrane production.

CONCLUSIONS

miR-125a-3p can effectively inhibit the function of VSMCs and the occurrence of vascular stenosis by targeting MAPK1. This study introduces a new molecular mechanism of PAD. We show that regulation of the miR-125a-3p level has the potential to provide a new treatment for PAD and other proliferative vascular diseases.

Metastasis-associated protein 1, modulated by miR-30c, promotes endometrial cancer progression through AKT/mTOR/4E-BP1 pathway

OBJECTIVE

Though metastasis-associated protein 1 (MTA1) is widely overexpressed in human cancers and is associated with advanced clinicopathological characteristics and survival in related diseases, the association between MTA1 and endometrial cancer (EC) is little known and needs to be studied.

METHODS

Western blot and immunohistochemistry were used to analyze protein expression level of cells and tissues, while real-time PCR was used for RNA detection. Bioinformatics tool analysis revealed the relationship between MTA1 and clinicopathological characteristics and survival. CCK-8 assay, colony-formation assay, cell scratch assay, and Transwell assay were performed to determine cell proliferation, migration and invasion abilities, respectively.

RESULTS

The expression level of MTA1 was significantly higher in human EC tissues than in normal endometrium. MTA1 expression was correlated positively with lymph nodes metastasis and poor survival rate in EC. Experimentally overexpressed MTA1 could promote cell proliferation, migration and invasion abilities of EC cell lines Ishikawa, HEC-1B, and RL-952, while reduction of MTA1 inhibited these cell biological behaviors. Moreover, MTA1 could also reverse the negative effect of miR-30c, a direct modulator of MTA1, on EC cells. Our research also revealed that overexpression of MTA1 contributed to EC tumor growth, while knockdown of MTA1 resulted in tumor growth inhibition. Additionally, the phosphorylation levels of mTOR (S2448) and 4E-BP1 (T37/46) changed significantly along with AKT (T308) under regulation of MTA1, both in vivo and vitro.

CONCLUSION

Our results showed that MTA1, as a downstream target of miR-30c, might promote EC progression via AKT/mTOR/4E-BP1 pathway, which indicated the potential therapy target of MTA1 in EC.

Genetic variations in miR-125 family and the survival of non-small cell lung cancer in Chinese population

To investigate the associations between the functional single nucleotide polymorphisms (SNPs) in the miR‐125 family and the survival of non‐small cell lung cancer (NSCLC) patients, we systematically selected six functional SNPs located in three pre‐miRNAs (miR‐125a, miR‐125b‐1, miR‐125b‐2). Cox proportional hazard regression analyses were conducted to estimate the crude and adjusted hazard ratios (HRs) and their 95% confidence intervals (CIs). Reporter gene luciferase assay was performed to examine the relationship between the SNPs and transcriptive activity of the miRNAs. The expression of miRNAs in different cells was detected using quantitative real‐time PCR assay. We found that rs2241490 (upstream of miR‐125b‐1, G > A, adjusted HR = 1.24, 95%CI = 1.05‐1.48, P = 0.014, in dominant model; adjusted HR = 1.18, 95%CI = 1.03‐1.35, P = 0.014, in additive model), rs512932 (upstream of miR‐125b‐1, A > G, dominant model: adjusted HR = 1.25, 95%CI = 1.05‐1.48, P = 0.013) and rs8111742 (upstream of miR‐125a, G > A, dominant model: adjusted HR = 0.84, 95%CI = 0.71‐1.00, P = 0.047) were associated with the prognosis of 1001 Chinese NSCLC patients. The combined analysis of the three SNPs related the number of risk alleles (rs2241490‐A, rs512932‐G and rs8111742‐G) to death risk of NSCLC in a locus‐dosage mode (P for trend <0.001). Furthermore, luciferase reporter gene assay showed significantly higher levels of luciferase activity with rs512932 variant G than that with A allele in 293T, SPC‐A1 and A549 cell lines. Besides, miR‐125b was highly expressed in lung cancer cells than the normal lung cell. Our study indicated that genetic variations in miR‐125 family were implicated in the survival of NSCLC patients. Larger population‐based and functional studies are needed to verify these findings.

Suppression of metastasis through inhibition of chitinase 3-like 1 expression by miR-125a-3p-mediated up-regulation of USF1

Rationale: Chitinase 3-like 1 (Chi3L1) protein is up-regulated in various diseases including solid cancers. According to Genome-Wide Association Study (GWAS)/Online Mendelian Inheritance in Man (OMIM)/Differentially Expressed Gene (DEG) analyses, Chi3L1 is associated with 38 cancers, and more highly associated with cancer compared to other oncogenes such as EGFR, TNFα, etc. However, the mechanisms and pathways by which Chi3L1 is associated with cancer are not clear. In current study, we investigated the role of Chi3L1 in lung metastasis. Methods: We performed the differentially expressed gene analysis to explore the genes which are associated with Chi3L1 using the web-based platform from Biomart. We investigated the metastases in lung tissues of C57BL/6 mice injected with B16F10 melanoma following treatment with Ad-shChi3L1. We also investigated the expression of USF1 and Chi3L1 in Chi3L1 KD mice lung tissues by Western blotting and IHC. We also analyzed lung cancer cells metastases induced by Chi3L1 using migration and cell proliferation assay in human lung cancer cell lines. The involvement of miR-125a-3p in Chi3L1 regulation was determined by miRNA qPCR and luciferase reporter assay. Results: We showed that melanoma metastasis in lung tissues was significantly reduced in Chi3L1 knock-down mice, accompanied by down-regulation of MMP-9, MMP-13, VEGF, and PCNA in Chi3L1 knock-down mice lung tissue, as well as in human lung cancer cell lines. We also found that USF1 was conversely expressed against Chi3L1. USF1 was increased by knock-down of Chi3L1 in mice lung tissues, as well as in human lung cancer cell lines. In addition, knock-down of USF1 increased Chi3L1 levels in addition to augmenting metastasis cell migration and proliferation in mice model, as well as in human cancer cell lines. Moreover, in human lung tumor tissues, the expression of Chi3L1 was increased but USF1 was decreased in a stage-dependent manner. Finally, Chi3L1 expression was strongly regulated by the indirect translational suppressing activity of USF1 through induction of miR-125a-3p, a target of Chi3L1. Conclusion: Metastases in mice lung tissues and human lung cancer cell lines were decreased by KD of Chi3L1. USF1 bound to the Chi3L1 promoter, however, Chi3L1 expression was decreased by USF1, despite USF1 enhancing the transcriptional activity of Chi3L1. We found that USF1 induced miR-125a-3p levels which suppressed Chi3L1 expression. Ultimately, our results suggest that lung metastasis is suppressed by knock-down of Chi3L1 through miR-125a-3p-mediated up-regulation of USF1.

Targeting cysteine-rich angiogenic inducer-61 by antibody immunotherapy suppresses growth and migration of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most frequent type of human lung cancer; lung cancer is responsible for the highest rates of cancer-associated mortality in the world. Cysteine-rich angiogenic inducer-61 (CYR-61) has been identified as a tumorigenesis-, development- and metastasis-related gene, and is reported to enhance proliferation, migration and invasion through hepatocyte growth factor (HGF)-induced scattering and the metastasis-inducing HGF/Met signaling pathway in tumor cells and xenograft models. CYR-61 is a protein that promotes human lung cancer cell metastasis and is closely related to the patient's prognosis in NSCLC. The purpose of the present study was to investigate whether CYR-61 may serve as a dual potential target for gene therapy of human NSCLC. In the present study, an antibody targeted against CYR-61 (anti-CYR-61) was constructed and the therapeutic effects and underlying mechanism of this antibody in NSCLC cells and mice with NSCLC was investigated. It was observed that NSCLC cell viability, migration and invasion were inhibited while cell apoptosis was induced by the neutralization of CYR-61 protein by anti-CYR-61. Western blotting demonstrated that extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) expression levels in NSCLC cells were decreased following treatment with anti-CYR-61. In addition, it was observed that inhibition of NSCLC cell viability was achieved by the suppression of the epithelial-mesenchymal transition signaling pathway. ERK and AKT phosphorylation levels were downregulated in NSCLC cells and tumors following anti-CYR-61 treatment. Analysis of a murine model indicated that tumor growth was inhibited and tumor metastasis was significantly suppressed (P<0.01) following anti-CYR-61 treatment for CYR-61. In conclusion, CYR-61 may serve as a potential target for gene therapy for the treatment of human NSCLC.

MicroRNA-183 suppresses the vitality, invasion and migration of human osteosarcoma cells by targeting metastasis-associated protein 1

The aim of the present study was to investigate the effects of microRNA (miR)-183 on vitality, invasion, metastasis and apoptosis in osteosarcoma (OS) cells, mediated by its binding to metastasis-associated protein 1 (MTA1). A dual luciferase reporter assay was performed to determine whether MTA1 was a direct target of miR-183. Cell Counting Kit-8, Transwell, scratch-wound healing, fluorescence-activated cell sorting andterminal deoxynucleotidyl transferase dUTP nick end labeling assays were also performed to investigate the effects of miR-183 expression on the proliferation, invasion, migration and apoptosis of MG63 cells. It was demonstrated that that MTA1 expression levels were significantly higher in OS tissues and MG63 cells compared with corresponding adjacent noncancerous tissues and normal cells, respectively, while miR-183 expression levels were significantly lower (both P<0.05). Furthermore, miR-183 overexpression downregulated MTA1 levels and inhibited cell proliferation (P<0.05), migration (P<0.05) and invasion (P<0.01), as well as promoting apoptosis (P<0.01) by binding to the 3'-untranslated region of MTA1. These results indicate that miR-183 inhibits the vitality, invasion, migration and apoptosis of the OS cell line MG63 by targeting MTA1. These findings may contribute to the development of novel clinical therapeutic approaches for the treatment of OS.

Metastasis-associated protein 2 promotes the metastasis of non-small cell lung carcinoma by regulating the ERK/AKT and VEGF signaling pathways

Non-small cell lung carcinoma (NSCLC) is the most common cause of cancer‑associated mortality in the world and accounts for ~85% of human lung cancers. Metastasis‑associated protein 2 (MTA2) is a component of the histone deacetylase complex and serves a role in tumor progression; however, the mechanism through which MTA2 is involved in the progression of NSCLC remains unclear. The aim of the present study was to investigate the expression and function of MTA2 and the MTA2‑mediated signaling pathway in NSCLC cells. Expression of MTA2 and its target genes was analyzed in MTA2‑overexpressing and anti‑MTA2 antibody (AbMTA2)‑treated NSCLC cells, as well as growth, migration, invasion and apoptotic‑resistance. The inhibitory effects on tumor formation were analyzed using AbMTA2‑treated NSCLC cells and in a mouse model. Histological assessment was conducted to analyze the expressions levels of extracellular signal‑regulated kinase (ERK), RAC‑α serine/threonine protein kinase (AKT) and vascular endothelial growth factor (VEGF) in experimental tumors. Results of the present study demonstrated that MTA2 was overexpressed in NSCLC cells. The growth, migration and invasion of NSCLC cells were markedly inhibited by AbMTA2. In addition, it was observed that the ERK/AKT and VEGF signaling pathways were both upregulated in MTA2‑overexpressing NSCLC cells, and downregulated following silencing of MTA2 activation. ERK and AKT phosphorylation levels were downregulated in NSCLC cells and tumors following MTA2 silencing. The in vivo study demonstrated that tumor growth was markedly inhibited following siRNA‑MTA2 treatment. In conclusion, the results of the present study suggested that MTA2 silencing may significantly inhibit the growth and aggressiveness of NSCLC cells. Results from the present study indicated that the mechanism underlying the MTA2‑mediated invasive potential of NSCLC cells involved the ERK/AKT and VEGF signaling pathways, which may be a potential therapeutic target for the treatment of NSCLC.

miR-125a-3p inhibits ERα transactivation and overrides tamoxifen resistance by targeting CDK3 in estrogen receptor-positive breast cancer

Tamoxifen (TAM) is a major adjuvant therapy for patients who are diagnosed with estrogen receptor-α (ER)-positive breast cancer; however, TAM resistance occurs often during treatment and the underlying mechanism is unclear. Here, we report that miR-125a-3p inhibits ERα transcriptional activity and, thus, ER+ breast cancer cell proliferation, which causes cell-cycle arrest at the G1/S stage, inducing apoptosis and suppressing tumor growth by targeting cyclin-dependent kinase 3 (CDK3) in vitro and in vivo. In addition, CDK3 and miR-125a-3p expression levels were measured in 37 cancerous tissues paired with noncancerous samples, and their expression levels were negatively associated with miR-125a-3p level. Of interest, miR-125a-3p level is down-regulated in MCF-7 TAM-resistant (TamR) cells. Of more importance, up-regulation of miR-125a-3p resensitizes MCF-7 TamR cells to TAM, which is dependent on CDK3 expression. These results suggest that miR-125a-3p can function as a novel tumor suppressor in ER+ breast cancer by targeting CDK3, which may be a potential therapeutic approach for TamR breast cancer therapy.-Zheng, L., Meng, X., Li, X., Zhang, Y., Li, C., Xiang, C., Xing, Y., Xia, Y., Xi, T. miR-125a-3p inhibits ERα transactivation and overrides tamoxifen resistance by targeting CDK3 in estrogen receptor-positive breast cancer.

MicroRNA expression profiling in placenta and maternal plasma in early pregnancy loss

Early pregnancy loss (EPL), also termed early miscarriage, is determined as the unintentional expulsion of an embryo or fetus prior to the 12th week of gestation. EPL frequency is ~15% in pregnancies. Fetal development and growth is associate with placental function and vessel development; therefore, the placental genome would represent a useful miscarriage model for (epi)genetic and genomic studies. An important factor of placental development and function is epigenetic regulation of gene expression. microRNAs (miRNAs) are the primary epigenetic regulators which have an important role in placental development and function. In the present study, maternal plasma and villous tissue were collected from 16 EPL cases in 6th-8th gestational weeks (GWs) and 8 abortions (control group) in 6th-8th GWs. Detection of the differences in miRNA expression was performed using microarrays and dysregulated miRNAs were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). miRNA microarray findings revealed that four miRNAs, including hsa-miRNA (miR)-125a-3p, hsa-miR-3663-3p, hsa-miR-423-5p and hsa-miR-575 were upregulated in tissue samples. In maternal plasma, two miRNAs (hsa-let-7c, hsa-miR-122) were upregulated and one miRNA (hsa-miR-135a) was downregulated. A total of 6 out of 7 dysregulated miRNAs were validated using RT-qPCR. The target genes of these dysregulated miRNAs were detected using the GeneSpring database. The aim of the present study was to detect dysregulated miRNAs in maternal plasma and villous cells and identify the target genes of dysregulated miRNAs and their associated pathways. The target gene analyses have revealed that the affected genes are primarily associated with cell migration, proliferation, implantation, adhesion, angiogenesis and differentiation and all are involved with EPL pathogenesis. Therefore, the present study may contribute to the understanding of the molecular mechanisms which lead to EPL.

Integrated Analyses Reveal Overexpressed Notch1 Promoting Porcine Satellite Cells' Proliferation through Regulating the Cell Cycle

Notch signaling as a conserved cell fate regulator is involved in the regulation of cell quiescence, proliferation, differentiation and postnatal tissue regeneration. However, how Notch signaling regulates porcine satellite cells (PSCs) has not been elucidated. We stably transfected Notch1 intracellular domain (N1ICD) into PSCs to analyze the gene expression profile and miRNA-seq. The analysis of the gene expression profile identified 295 differentially-expressed genes (DEGs) in proliferating-N1ICD PSCs (P-N1ICD) and nine DEGs on differentiating-N1ICD PSCs (D-N1ICD), compared with that in control groups (P-Control and D-Control, respectively). Analyzing the underlying function of DEGs showed that most of the upregulated DEGs enriched in P-N1ICD PSCs are related to the cell cycle. Forty-four and 12 known differentially-expressed miRNAs (DEMs) were identified in the P-N1ICD PSCs and D-N1ICD PSCs group, respectively. Furthermore, we constructed the gene-miRNA network of the DEGs and DEMs. In P-N1ICD PSCs, miR-125a, miR-125b, miR-10a-5p, ssc-miR-214, miR-423 and miR-149 are downregulated hub miRNAs, whose corresponding hub genes are marker of proliferation Ki-67 (MKI67) and nuclear receptor binding SET domain protein 2 (WHSC1). By contrast, miR-27a, miR-146a-5p and miR-221-3p are upregulated hub miRNAs, whose hub genes are RUNX1 translocation partner 1 (RUNX1T1) and fibroblast growth factor 2 (FGF2). All the hub miRNAs and genes are associated with cell proliferation. Quantitative RT-PCR results are consistent with the gene expression profile and miRNA-seq results. The results of our study provide valuable information for understanding the molecular mechanisms underlying Notch signaling in PSCs and skeletal muscle development.

MiR-652-3p is upregulated in non-small cell lung cancer and promotes proliferation and metastasis by directly targeting Lgl1

Our previous study found that miR-652-3p is markedly upregulated in the serum of patients with NSCLC and suggesting that miR-652-3p is a potential biomarker for the early diagnosis of NSCLC. In this study, we detected the expression of miR-652-3p in NSCLC tumor tissues and cell lines and investigated the effect of miR-652-3p on the proliferation and metastasis of NSCLC cells. Our results showed that the expression of miR-652-3p was significantly upregulated in tumor tissues of 50 patients with NSCLC, and it was significantly higher in patients with positive lymph node metastasis, advanced TNM stage and poor prognosis. Using functional analyses by overexpressing or suppressing miR-652-3p in NSCLC cells, we demonstrated that miR-652-3p promoted cell proliferation, migration, invasion and inhibited cell apoptosis. Moreover, the lethal(2) giant larvae 1 (Lgl1) was identified as a direct and functional target of miR-652-3p. Overexpression or knockdown of miR-652-3p led to decreased or increased expression of Lgl1 protein, and the binding site mutation of LLGL1 3'UTR abrogated the responsiveness of the luciferase reporters to miR-652-3p. Overexpression of Lgl1 partially attenuated the function of miR-652-3p. Collectively, these results revealed that miR-652-3p execute a tumor-promoter function in NSCLC through direct binding and regulating the expression of Lgl1.

Long noncoding RNA NORAD, a novel competing endogenous RNA, enhances the hypoxia-induced epithelial-mesenchymal transition to promote metastasis in pancreatic cancer

Background

Pancreatic cancer, one of the top two most fatal cancers, is characterized by a desmoplastic reaction that creates a dense microenvironment, promoting hypoxia and inducing the epithelial-to-mesenchymal transition (EMT) to facilitate invasion and metastasis. Recent evidence indicates that the long noncoding RNA NORAD may be a potential oncogenic gene and that this lncRNA is significantly upregulated during hypoxia. However, the overall biological role and clinical significance of NORAD remains largely unknown.

Methods

NORAD expression was measured in 33 paired cancerous and noncancerous tissue samples by real-time PCR. The effects of NORAD on pancreatic cancer cells were studied by overexpression and knockdown in vitro. Insights into the mechanism of competitive endogenous RNAs (ceRNAs) were gained from bioinformatics analyses and luciferase assays. In vivo, metastatic potential was identified using an orthotopic model of PDAC and quantified using bioluminescent signals. Alterations in RhoA expression and EMT levels were identified and verified by immunohistochemistry and Western blotting.

Results

NORAD is highly expressed in pancreatic cancer tissues and upregulated in hypoxic conditions. NORAD upregulation is correlated with shorter overall survival in pancreatic cancer patients. Furthermore, NORAD overexpression promoted the migration and invasion of pancreatic carcinoma cells, while NORAD depletion inhibited EMT and metastasis in vitro and in vivo. In particular, NORAD may function as a ceRNA to regulate the expression of the small GTP binding protein RhoA through competition for hsa-miR-125a-3p, thereby promoting EMT.

Conclusions

Elevated expression of NORAD in pancreatic cancer tissues is linked to poor prognosis and may confer a malignant phenotype upon tumor cells. NORAD may function as a ceRNA to regulate the expression of the small GTP binding protein RhoA through competition for hsa-miR-125a-3p. This finding may contribute to a better understanding of the role played by lncRNAs in hypoxia-induced EMT and provide a potential novel diagnostic and therapeutic target for pancreatic cancer.

Electronic supplementary material

The online version of this article (10.1186/s12943-017-0738-0) contains supplementary material, which is available to authorized users.

MTA1 expression in human cancers - Clinical and pharmacological significance

Remarkably, majority of the cancer deaths are due to metastasis, not because of primary tumors. Metastasis is one of the important hallmarks of cancer. During metastasis invasion of primary tumor cells from the site of origin to a new organ occurs. Metastasis associated proteins (MTAs) are a small family of transcriptional coregulators that are closely associated with tumor metastasis. These proteins are integral components of nuclear remodeling and deacetylation complex (NuRD). By virtue of being integral components of NuRD, these proteins regulate the gene expression by altering the epigenetic changes such as acetylation and methylation on the target gene chromatin. Among the MTA proteins, MTA1 expression is very closely correlated with the aggressiveness of several cancers that includes breast, liver, colon, pancreas, prostate, blood, esophageal, gastro-intestinal etc. Considering its close association with aggressiveness in human cancers, MTA1 may be considered as a potential therapeutic target for cancer treatment. The recent developments in its crystal structure further strengthened the idea of developing small molecule inhibitors for MTA1. In this review, we discuss the recent trends on the diverse functions of MTA1 and its role in various cancers, with the focus to consider MTA1 as a 'druggable' target in the control of human cancers.

MACC‑1 antibody target therapy suppresses growth and migration of non‑small cell lung cancer

Non‑small‑cell lung cancer (NSCLC) accounts for ~80% of human lung cancers that result in mortalities worldwide. Metastasis‑associated in colon cancer‑1 (MACC‑1) has been demonstrated to be significantly expressed in cases of NSCLC and promotes tumor cell migration and metastasis through transactivation of the metastasis‑inducing hepatocyte growth factor/MET proto‑gene, receptor tyrosine kinase (HGF/MET) signaling pathway. The present study constructed a chimeric antibody (Chanti‑MACC‑1) targeting MACC‑1 and investigated its potential as a molecular therapeutic target in the treatment of NSCLC therapy. The expression of MACC‑1 was detected by reverse transcription‑quantitative polymerase chain reaction and western blotting in lung cancer cell lines and tissues. MTT assay was used to detect proliferation of A549 cells treated by Chanti‑MACC‑1, whereas the functional and regulatory effects of Chanti‑MACC‑1 in the migration and metastasis of NSCLC cells was investigated by a cell invasion assay. The therapeutic effect and survival time was observed in animal models. The results demonstrated that MACC‑1 expression was increased and overexpression of MACC‑1 promoted the progression of the cell cycle, significantly promoted NSCLC cell growth and enhanced tumor migration and invasion through the HGF/MET signaling pathway. It was further demonstrated that Chanti‑MACC‑1 efficiently suppressed MACC‑1 expression and significantly inhibited NSCLC cell proliferation, migration and invasion by blocking the HGF/MET signaling pathway. The data revealed that Chanti‑MACC‑1 was not only beneficial for tumor remission, however additionally contributed to the long‑term survival of NSCLC ‑bearing mice. The findings of the present study indicated that MACC‑1 was significantly upregulated and promoted tumor cell growth and migration in NSCLC cells and tissues via transactivation of the metastasis‑inducing HGF/MET signaling pathway. However, Chanti‑MACC‑1significantly inhibited tumor growth and metastasis, which suggested that MACC‑1 may be essential for tumor initiation and progression by negatively regulating tumor suppressors.

MicroRNA-125a-3p downregulation correlates with tumorigenesis and poor prognosis in patients with non-small cell lung cancer

MicroRNA (miR)-125a-3p is derived from the 3'-end of pre-miR-125a, which is associated with several types of cancer, such as gastric and prostate cancer, and glioma. The aim of the present study was to identify the prognostic significance of miR-125a-3p expression levels in patients with NSCLC. The gene expression omnibus database was used to analyze miR-125a-3p expression in NSCLC in silico, and 148 NSCLC samples and 30 adjacent normal lung tissue specimens were analyzed for the expression of miR-125a-3p by qPCR. The results showed that the expression levels of miR-125a-3p in the adjacent normal tissues was higher than the expression level in the NSCLC tissues. There were several clinical parameters demonstrated to be associated with miR-125a-3p expression, such as lymph node metastasis, tumor node metastasis classification of malignant tumor stage and tumor diameter. Furthermore, high expression levels of miR-125a-3p with chemotherapy prolonged the overall survival rate and disease free survival rate compared with untreated patients with low expression of miR-125a-3p. Thus, miR-125a-3p is a significant prognostic biomarker for patients with NSCLC, from which a novel therapeutic strategy to combat NSCLC may be derived.

MicroRNA expression profiling of porcine mammary epithelial cells after challenge with Escherichia coli in vitro

Background

Coliform mastitis is a symptom of postpartum dysgalactia syndrome (PDS), a multifactorial infectious disease of sows. Our previous study showed gene expression profile change after bacterial challenge of porcine mammary epithelial cells (PMECs). These mRNA expression changes may be regulated through microRNAs (miRNAs) which play critical roles in biological processes. Therefore, miRNA expression profile was investigated in PMECs.

Results

PMECs were isolated from three lactating sows and challenged with heat-inactivated potential mastitis-causing pathogen Escherichia coli (E. coli) for 3 h and 24 h, in vitro. At 3 h post-challenge with E. coli, target gene prediction identified a critical role of miRNAs in regulation of host immune responses and homeostasis of PMECs mediated by affecting pathways including cytokine binding (miR-202, miR-3277, miR-4903); IL-10/PPAR signaling (miR-3277, miR-4317, miR-548); and NF-ĸB/TNFR2 signaling (miR-202, miR-2262, miR-885-3p). Target genes of miRNAs in PMECs at 24 h were significantly enriched in pathways associated with interferon signaling (miR-210, miR-23a, miR-1736) and protein ubiquitination (miR-125, miR-128, miR-1280).

Conclusions

This study provides first large-scale miRNA expression profiles and their predicted target genes in PMECs after contact with a potential mastitis-causing E. coli strain. Both, highly conserved miRNAs known from other species as well as novel miRNAs were identified in PMECs, representing candidate predictive biomarkers for PDS. Time-dependent pathogen clearance suggests an important role of PMECs in inflammatory response of the first cellular barrier of the porcine mammary gland.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4070-2) contains supplementary material, which is available to authorized users.

Altered Expressions of miR-1238-3p, miR-494, miR-6069, and miR-139-3p in the Formation of Chronic Brucellosis

Brucellosis is a zoonotic disease that is still endemic in developing countries. Despite early diagnosis and treatment of patients, chronic infections are seen in 10–30% of patients. In this study, we aimed to investigate the immunological factors that play roles in the transition of brucellosis from acute infection into chronic infection. Here, more than 2000 miRNAs were screened in peripheral blood mononuclear cells (PBMCs) of patients with acute or chronic brucellosis and healthy controls by using miRNA array, and the results of the miRNA array were validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Four miRNAs were expressed in the chronic group but were not expressed in acute and control groups. Among these miRNAs, the expression level of miR-1238-3p was increased while miR-494, miR-6069, and miR-139-3p were decreased (p < 0.05, fold change > 2). These miRNAs have the potential to be markers for chronic cases. The differentially expressed miRNAs and their predicted target genes involved in endocytosis, regulation of actin cytoskeleton, MAPK signaling pathway, and cytokine-cytokine receptor interaction and its chemokine signaling pathway indicate their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human PBMC to clarify the mechanism of inveteracy in brucellosis.

Migration and epithelial-to-mesenchymal transition of lung cancer can be targeted via translation initiation factors eIF4E and eIF4GI

Metastasis underlies cancer morbidity and accounts for disease progression and significant death rates generally and in non-small cell lung cancer (NSCLC) particularly. Therefore, it is critically important to understand the molecular events that regulate metastasis. Accumulating data portray a central role for protein synthesis, particularly translation initiation (TI) factors eIF4E and eIF4G in tumorigenesis and patients' survival. We have published that eIF4E/eIF4GI activities and consequently NSCLC cell migration are modulated by bone-marrow mesenchymal stem cell secretomes, suggesting a role for TI in metastasis. Here, we aimed to expand our understanding of the TI factors significance to NSCLC characteristics, particularly epithelial-to-mesenchymal transition (EMT) and migration, supportive of metastasis. In a model of NSCLC cell lines (H1299, H460), we inhibited eIF4E/eIF4GI's expressions (siRNA, ribavirin) and assessed NSCLC cell lines' migration (scratch), differentiation (EMT, immunoblotting), and expression of select microRNAs (qPCR). Initially, we determined an overexpression of several TI factors (eIF4E, eIF4GI, eIF4B, and DHX29) and their respective targets in NSCLC compared with normal lung samples (70-350%↑, P<0.05). Knockdown (KD) of eIF4E/eIF4GI in NSCLC cell lines (70%↓, P<0.05) also manifested in decreased target levels (ERα, SMAD5, NFkB, CyclinD1, c-MYC, and HIF1α) (20-50%↓, P<0.05). eIF4E/eIF4GI KD also attenuated cell migration (60-75%↓, P<0.05), EMT promoters (15-90%↓, P<0.05), and enhanced EMT suppressors (30-380%↑, P<0.05). The importance of eIF4E KD to NSCLC phenotype was further corroborated with its inhibitor, ribavirin. Changes in expression of essential microRNAs implicated in NSCLC cell migration concluded the study (20-100%, P<0.05). In summary, targeting eIF4E/eIF4GI reduces migration and EMT, both essential for metastasis, thereby underscoring the potential of TI targeting in NSCLC therapy, especially the already clinically employed agents (ribavirin/4EGI). Comparison of these findings with previously reported effects of eIF4E/eIF4GI KD in multiple myeloma suggests a collective role for these TI factors in cancer progression.

Effects of Per2 overexpression on growth inhibition and metastasis, and on MTA1, nm23-H1 and the autophagy-associated PI3K/PKB signaling pathway in nude mice xenograft models of ovarian cancer

The aim of the present study was to evaluate the association between Period2 (Per2) and the occurrence and development of ovarian cancer, in addition to evaluating the effect of this gene on the growth and metastasis of ovarian cancer in nude mice xenograft models. The detection of Per2 by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting methods at various stages of ovarian cancer in tumor tissue samples was conducted. Nude mice xenograft models of ovarian cancer were constructed using an ovarian cancer cell line and, using a gene transfection technique, exogenous infusion of the recombinant gene, Per2, was performed. To assess for the successful and stable expression of Per2 in the tumor tissue, levels of Per2 expression in the nude mice xenograft models were detected by RT‑qPCR. During the experimental period, the tumor volumes were measured every three days. Two weeks following treatment cessation, the nude mice were sacrificed and the tumor weight and volume were measured. Furthermore, detection of the changes in expression levels of metastasis‑associated gene 1 (MTA‑1) and tumor metastasis suppressor gene, non‑metastasis protein 23‑H1 (nm23‑H1), and the expression change of autophagy‑associated signal transduction pathway, phosphatidylinositol 3‑kinase (PI3K)/protein kinase B (PKB) kinase were analyzed. The findings demonstrated that with ovarian cancer stage development, the expression of Per2 gradually reduced or ceased. In addition, exogenous Per2 was successfully and stably expressed in nude mice tumor tissue samples. Furthermore, in the Per2 overexpression group, MTA‑1 protein expression was significantly reduced when compared with the phosphate‑buffered saline (PBS) control and empty plasmid groups, while nm23‑H1 protein expression was significantly higher when compared with those two groups. The expression levels of PI3K and PKB kinase, which are marker proteins of the autophagy associated signaling pathway PI3K/PKB, were significantly downregulated, when compared with the PBS control and empty plasmid groups (P<0.001). Thus, it was demonstrated that Per2 is closely associated with the development of ovarian cancer, and late‑stage ovarian cancer is associated with Per2 mutation or deletion. Per2 overexpression, via exogenous infusion reduced the ovarian cancer growth rate, which was demonstrated by a significant increase in the tumor inhibition rate. In addition, Per2 may inhibit the expression of MTA‑1 and promote the expression of nm23‑H1 to restrict ovarian tumor growth and metastasis. Finally, it is hypothesized that Per2 affects autophagy by interfering with the PI3K/PKB signaling pathway, causing inhibition of tumor angiogenesis in order to inhibit tumor growth.

The role of microRNA in metastatic processes of non-small cell lung carcinoma

BACKGROUND

MicroRNAs are small non-coding one-stranded RNA molecules that play an important role in the post-transcriptional regulation of genes. Bioinformatic predictions indicate that each miRNA can regulate hundreds of target genes. MicroRNA expression can be associated with various cellular processes leading to the metastasis of malignant tumours including non-small cell lung carcinoma. This review summarizes current knowledge on the role of microRNAs in NSCLC metastasis to the brain and lymph nodes.

METHODS

A search of the NCBI/PubMed database for publications on expression levels and the mechanisms of microRNA action in NSCLC metastasis.

RESULTS AND CONCLUSION

Dysregulation of microRNAs in NSCLC can be associated with brain and lymph node metastasis. There are differences in microRNA expression profiling between NSCLC with and without metastases but it is currently not possible to reliably predict the site of metastasis in NSCLC. Based on data from RNAmicroarrays, bioinformatics analysis is able to predict the target genes of highlighted microRNAs, providing us with complex information about cancer cell features such as enhanced proliferation, migration and invasion. Such microRNAs may then be knocked-down using siRNAs or substituted with miRNA mimics. RNA microarray profiling may thus be a useful tool to select up- or down-regulated microRNAs. A number of authors suggest that microRNAs could serve as biomarkers and therapeutic targets in the treatment of NSCLC metastasis.

Structure, expression and functions of MTA genes

Metastatic associated proteins (MTA) are integrators of upstream regulatory signals with the ability to act as master coregulators for modifying gene transcriptional activity. The MTA family includes three genes and multiple alternatively spliced variants. The MTA proteins neither have their own enzymatic activity nor have been shown to directly interact with DNA. However, MTA proteins interact with a variety of chromatin remodeling factors and complexes with enzymatic activities for modulating the plasticity of nucleosomes, leading to the repression or derepression of target genes or other extra-nuclear and nucleosome remodeling and histone deacetylase (NuRD)-complex independent activities. The functions of MTA family members are driven by the steady state levels and subcellular localization of MTA proteins, the dynamic nature of modifying signals and enzymes, the structural features and post-translational modification of protein domains, interactions with binding proteins, and the nature of the engaged and resulting features of nucleosomes in the proximity of target genes. In general, MTA1 and MTA2 are the most upregulated genes in human cancer and correlate well with aggressive phenotypes, therapeutic resistance, poor prognosis and ultimately, unfavorable survival of cancer patients. Here we will discuss the structure, expression and functions of the MTA family of genes in the context of cancer cells.