miR-29b Mediates NF-κB Signaling in KRAS-Induced Non–Small Cell Lung Cancers

The Role of A20 in Cancer: Friend or Foe?

A20 is a ubiquitin-editing enzyme that has emerged as a key regulator of inflammatory signaling with paradoxical roles in cancer. Acting as both an oncogene and a tumor suppressor gene depending on the cellular context, A20 modulates important cell pathways, such as NF-κB signaling and autophagy. In this review, we summarize the dual roles of A20 in tumorigenesis, highlighting its ability to promote tumor progression in cancers, such as breast and melanoma, while functioning as a tumor suppressor in lymphomas and hepatocellular carcinoma. We discuss the interplay of A20 with autophagy, a process that is important for maintaining cellular homeostasis and influencing tumor dynamics. By integrating recent findings, we provide insight into how dysregulation of A20 and its associated pathways can either suppress or drive cancer development, which may lead to improved therapeutic intervention.

Ultrasensitive Method Enables Liquid Biopsy for the Precise Detection of Circulating MicroRNAs

Due to invasive and serial examinations of bioactive molecules, liquid biopsy (LB) has emerged as a rapid and reliable solution for early disease detection and monitoring. Developing portable devices with high specificity and sensitivity for LB is highly valuable. To realize a generalized approach to increase the sensitivity of LB, we developed an ultrasensitive diagnostic biochip based on the amplification of miRNA by recombinase polymerase amplification and the significant enhancement of fluorescence signals by photonic crystal (PC) materials. The PCs-RPA biochip has a detection limit as low as 0.24 aM, a wide linear range of 8 orders of magnitude, and excellent specificity. Such advantages realize the accurate detection of circulating miRNAs with very low content in clinical serum samples for the precise diagnosis of nonsmall cell lung cancer.

miRNA Signatures in Bronchopulmonary Dysplasia: Implications for Biomarkers, Pathogenesis, and Therapeutic Options

Bronchopulmonary dysplasia (BPD) is a chronic lung disease in premature infants characterized by alveolar dysplasia, vascular simplification and dysmorphic vascular development. Supplemental oxygen and mechanical ventilation commonly used as life-saving measures in premature infants may cause BPD. microRNAs (miRNAs), a class of small, non-coding RNAs, regulate target gene expression mainly through post-transcriptional repression. miRNAs play important roles in modulating oxidative stress, proliferation, apoptosis, senescence, inflammatory responses, and angiogenesis. These cellular processes play pivotal roles in the pathogenesis of BPD. Accumulating evidence demonstrates that miRNAs are dysregulated in the lung of premature infants with BPD, and in animal models of this disease, suggesting contributing roles of dysregulated miRNAs in the development of BPD. Therefore, miRNAs are considered promising biomarker candidates and therapeutic agents for this disease. In this review, we discuss how dysregulated miRNAs and their modulation alter cellular processes involved in BPD. We then focus on therapeutic approaches targeting miRNAs for BPD. This review provides an overview of miRNAs as biomarkers, and highlights potential pathogenic roles, and therapeutic strategies for BPD using miRNAs.

miR-29c-3p acts as a tumor promoter by regulating β-catenin signaling through suppressing DNMT3A, TET1 and HBP1 in ovarian carcinoma

Ovarian Carcinoma (OvCa) is characterized by rapid and sustained growth, activated invasion and metastasis. Studies have shown that microRNAs recruit and alter the expression of key regulators to modulate carcinogenesis. Here, we find that miR-29c-3p is increased in benign OvCa and malignant OvCa compared to normal ovary. Univariate and multivariate analyses report that miR-29c-3p overexpression is associated with poor prognosis in OvCa. Furthermore, we investigate that expression of miR-29c-3p is inversely correlated to DNA methyltransferase (DNMT) 3 A and Ten-Eleven-Translocation enzyme TET1. The high-throughput mRNA sequencing, bioinformatics analysis and pharmacological studies confirm that aberrant miR-29c-3p modulates tumorigenesis in OvCa cells, including epithelial-mesenchymal transition (EMT), proliferation, migration, and invasion. This modulation occurs through the regulation of β-catenin signaling by directly targeting 3'UTR of DNMT3A, TET1 and the HMG box transcription factor HBP1 and suppressing their expression. The further 3D spheres assay clearly shows the regulatory effects of miR-29c-3p on OvCa tumorigenesis. Additionally, the receiver operating characteristic (ROC) curve analysis of miR-29c-3p and the clinical detection/diagnostic biomarker CA125 suggests that miR-29c-3p may be conducive for clinical diagnosis or co-diagnosis of OvCa. These findings support miR-29c-3p functions as a tumor promoter by targeting its functional targets, providing new potential biomarker (s) for precision medicine strategies in OvCa.

Nrf2 regulates downstream genes by targeting miR-29b in severe asthma and the role of grape seed proanthocyanidin extract in a murine model of steroid-insensitive asthma

CONTEXT

Grape seed proanthocyanidin extract (GSPE) is effective in treating severe asthma (SA).

OBJECTIVE

To examine the relationship between Nrf2-miR-29b axis and SA, and to detect whether preventive use of GSPE relieves SA via it.

MATERIALS AND METHODS

We recruited 10 healthy controls, 10 patients with non-severe asthma (nSA), and 9 patients with SA from February 2017 to December 2017. Peripheral blood mononuclear cells from these volunteers were extracted. A murine model of steroid-insensitive asthma was established in six-week-old female BALB/c mice that were sensitised and challenged with OVA, Al(OH)₃ and LPS for 31 days. Mice in the treated groups were injected with DXM (5 mg/kg/d), with or without GSPE (100 mg/kg/d). Control group received PBS. We performed quantitative real-time PCR, western blot and luciferase reporter assay in animal and cell models.

RESULTS

SA group demonstrated significantly lower concentrations of Nrf2 protein, Nrf2 mRNA, and miR-29b than nSA group and control group. Conversely, higher levels of platelet derived growth factor C (PDGFC), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), and collagen type III alpha 1 (COL3A1) were measured in SA than in the other two groups. PDGFC, PIK3R1, and COL3A1 were the target genes of miR-29b. GSPE + DXM significantly elevated the expression of Nrf2 (+188%), Nrf2 mRNA (+506%), and miR-29b (+201%), and significantly reduced the expression of PDGFC (-72%), PIK3R1 (-40%), and COL3A1 (-65%) compared with OVA + LPS.

CONCLUSIONS

Nrf2-miR-29b axis is involved in the pathogenesis of SA. GSPE, as an adjuvant drug, maybe a potential therapeutic agent for SA.

Pleiotropy of PP2A Phosphatases in Cancer with a Focus on Glioblastoma IDH Wildtype

Serine/Threonine protein phosphatase 2A (PP2A) is a heterotrimeric (or occasionally, heterodimeric) phosphatase with pleiotropic functions and ubiquitous expression. Despite the fact that they all contribute to protein dephosphorylation, multiple PP2A complexes exist which differ considerably by their subcellular localization and their substrate specificity, suggesting diverse PP2A functions. PP2A complex formation is tightly regulated by means of gene expression regulation by transcription factors, microRNAs, and post-translational modifications. Furthermore, a constant competition between PP2A regulatory subunits is taking place dynamically and depending on the spatiotemporal circumstance; many of the integral subunits can outcompete the rest, subjecting them to proteolysis. PP2A modulation is especially important in the context of brain tumors due to its ability to modulate distinct glioma-promoting signal transduction pathways, such as PI3K/Akt, Wnt, Ras, NF-κb, etc. Furthermore, PP2A is also implicated in DNA repair and survival pathways that are activated upon treatment of glioma cells with chemo-radiation. Depending on the cancer cell type, preclinical studies have shown some promise in utilising PP2A activator or PP2A inhibitors to overcome therapy resistance. This review has a special focus on "glioblastoma, IDH wild-type" (GBM) tumors, for which the therapy options have limited efficacy, and tumor relapse is inevitable.

Study of KRAS-Related miRNA Expression in Colorectal Cancer

Introduction

Colorectal cancer (CRC) is one of the most common digestive system tumors and seriously threatens the lives of patients. The choice of treatment options and the prognosis of CRC patients are closely related to the KRAS genotype. Notably, microRNAs (miRNAs) have great application value in the diagnosis and treatment of CRC.

Methods

The current study used qRT–PCR to analyze the expression of KRAS-targeting miRNAs and determine the correlation between miRNA expression and KRAS gene expression among patients with varying genotypes. The effect of the KRAS gene on the prognosis of patients with cancer was determined.

Results

Eighty-two differentially expressed miRNAs were identified between CRC tumor and normal tissues: 58 dysregulated miRNAs were identified in patients with KRAS mutations, and 62 aberrantly expressed miRNAs were detected in patients with wild-type KRAS. Thirteen miRNAs were abnormally expressed in KRAS-mutant patients compared with KRAS wild-type patients. Some miRNAs not only acted as biomarkers for CRC but also indicated the genotype of KRAS.

Conclusion

This finding is very important for patients who must choose from clinical treatment options based on KRAS results. Thus, the abnormal expression of miRNAs has great application potential for the selection of chemotherapy regimens for patients with cancer. The relationship between differential miRNA expression and the KRAS genotype is very important for studying related mechanisms in CRC.

PESV represses non-small cell lung cancer cell malignancy through circ_0016760 under hypoxia

Background

Non-small cell lung cancer (NSCLC) accounts for more than 80% of lung cancers, which is the most common malignant tumor worldwide. Polypeptide extract from scorpion venom (PESV) has been reported to inhibit NSCLC process. The present study aims to reveal the roles of PESV in NSCLC progression under hypoxia and the inner mechanism.

Methods

The expression levels of circular RNA 0016760 (circ_0016760) and microRNA-29b (miR-29b) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was determined by western blot and immunohistochemistry assays. Cell migration, invasion, proliferation and tube formation were investigated by transwell, cell colony formation, 3-(4,5-Dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide and tube formation assays. The impacts between PESV and circ_0016760 overexpression on tumor growth in vivo were investigated by in vivo tumor formation assay.

Results

Circ_0016760 expression was dramatically upregulated in NSCLC tissues and cells, compared with adjacent lung tissues and cells, respectively. PESV treatment downregulated circ_0016760 expression. Circ_0016760 silencing or PESV treatment repressed cell migration, invasion, proliferation and tube formation under hypoxia in NSCLC cells. Circ_0016760 overexpression restored the effects of PESV treatment on NSCLC process under hypoxia. Additionally, circ_0016760 acted as a sponge of miR-29b, and miR-29b bound to HIF1A. Meanwhile, miR-29b inhibitor impaired the influences of circ_0016760 knockdown on NSCLC process under hypoxia. Further, ectopic circ_0016760 expression restrained the effects of PESV exposure on tumor formation in vivo.

Conclusion

Circ_0016760 overexpression counteracted PESV-induced repression of NSCLC cell malignancy and angiogenesis under hypoxia through miR-29b/HIF1A axis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02336-6.

Cell Behavior of Non-Small Cell Lung Cancer Is at EGFR and MicroRNAs Hands

Lung cancer is a complex disease associated with gene mutations, particularly mutations of Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) and epidermal growth factor receptor (EGFR). Non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) are the two major types of lung cancer. The former includes most lung cancers (85%) and are commonly associated with EGFR mutations. Several EGFR-tyrosine kinase inhibitors (EGFR-TKIs), including erlotinib, gefitinib, and osimertinib, are effective therapeutic agents in EGFR-mutated NSCLC. However, their effectiveness is limited by the development (acquired) or presence of intrinsic drug resistance. MicroRNAs (miRNAs) are key gene regulators that play a profound role in the development and outcomes for NSCLC via their role as oncogenes or oncosuppressors. The regulatory role of miRNA-dependent EGFR crosstalk depends on EGFR signaling pathway, including Rat Sarcoma/Rapidly Accelerated Fibrosarcoma/Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase 1/2 (Ras/Raf/MEK/ERK1/2), Signal Transducer and Activator of Transcription (STAT), Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B Cells (NF-kB), phosphoinositide 3-kinase/protein kinase B (PI3K/AKT), Janus kinase 1 (JAK1), and growth factor receptor-bound protein 2 (GRB2). Dysregulated expression of miRNAs affects sensitivity to treatment with EGFR-TKIs. Thus, abnormalities in miRNA-dependent EGFR crosstalk can be used as diagnostic and prognostic markers, as well as therapeutic targets in NSCLC. In this review, we present an overview of miRNA-dependent EGFR expression regulation, which modulates the behavior and progression of NSCLC.

Synergistic effects of FGFR1 and PLK1 inhibitors target a metabolic liability in KRAS-mutant cancer

KRAS oncoprotein is commonly mutated in human cancer, but effective therapies specifically targeting KRAS-driven tumors remain elusive. Here, we show that combined treatment with fibroblast growth factor receptor 1 (FGFR1) and polo-like kinase 1 (PLK1) inhibitors evoke synergistic cytotoxicity in KRAS-mutant tumor models in vitro and in vivo. Pharmacological and genetic suppression of FGFR1 and PLK1 synergizes to enhance anti-proliferative effects and cell death in KRAS-mutant lung and pancreatic but not colon nor KRAS wild-type cancer cells. Mechanistically, co-targeting FGFR1 and PLK1 upregulates reactive oxygen species (ROS), leading to oxidative stress-activated c-Jun N-terminal kinase (JNK)/p38 pathway and E2F1-induced apoptosis. We further delineate that autophagy protects from PLK1/FGFR1 inhibitor cytotoxicity and that antagonizing the compensation mechanism by clinically approved chloroquine fully realizes the therapeutic potential of PLK1 and FGFR1 targeting therapy, producing potent and durable responses in KRAS-mutant patient-derived xenografts and a genetically engineered mouse model of Kras-induced lung adenocarcinoma. These results suggest a previously unappreciated role for FGFR1 and PLK1 in the surveillance of metabolic stress and demonstrate a synergistic drug combination for treating KRAS-mutant cancer.

MicroRNA-29b-3p Inhibits the Migration and Invasion of Gastric Cancer Cells by Regulating the Autophagy-Associated Protein MAZ

Purpose

The purpose of this study was to investigate the relationship between microRNA-29b-3p (miR-29b-3p) and myc-associated zinc finger protein (MAZ) expression and the effects of this interaction on the proliferation, migration, and invasion of gastric cancer cells.

Methods

qPCR and Western blots were used to detect the expression of miR-29b-3p and MAZ. The dual luciferase reporter gene system was used to explore whether MAZ is the target of miR-29b-3p. Cell function experiments and a mouse tumorigenesis model were used to determine the effects of miR-29b-3p overexpression and MAZ depletion on proliferation, migration, and invasion in gastric cancer cell lines and on tumor growth.

Results

The expression level of miR-29b-3p was low and the expression level of MAZ was high in gastric cancer cells compared with normal human gastric mucosal epithelial cells. MAZ was the target gene of miR-29b-3p. The upregulation of miR-29b-3p reduces the expression of MAZ. Overexpression of miR-29b-3p and downregulation of MAZ inhibited the proliferation and migration of cancer cells and induced apoptosis by controlling the expression of autophagy-related proteins. MiR-29b-3p mimics inhibit tumor growth in mice.

Conclusion

MiR-29b-3p inhibits the migration and invasion of gastric cancer cells by regulating the autophagy-related protein MAZ.

The dual roles of A20 in cancer

A20 is a prototypical anti-inflammatory molecule that is linked to multiple human diseases, including cancers. The role of A20 as a tumor suppressor was first discovered in B cell lymphomas. Subsequent studies revealed the dual roles of A20 in solid cancers. This review focuses on the roles of A20 in different cancer types to demonstrate that the effects of A20 are cancer type-dependent. A20 plays antitumor roles in colorectal carcinomas and hepatocellular carcinomas, whereas A20 acts as an oncogene in breast cancers, gastric cancers and melanomas. Moreover, the roles of A20 in the setting of glioma therapy are context-dependent. The action mechanisms of A20 in different types of cancer are summarized. Additionally, the role of A20 in antitumor immunity is discussed. Furthermore, some open questions in this rapidly advancing field are proposed. Exploration of the actions and molecular mechanisms of A20 in cancer paves the way for the application of A20-targeting approaches in future cancer therapy.

Non-coding RNAs related to angiogenesis in gynecological cancer

Gynecological cancer affects the female reproductive system, including ovarian, uterine, endometrial, cervical, vulvar, and vaginal tumors. Non-coding RNAs (ncRNAs), and in particular microRNAs, function as regulatory molecules, which can control gene expression in a post-transcriptional manner. Normal physiological processes like cellular proliferation, differentiation, and apoptosis, and pathological processes such as oncogenesis and metastasis are regulated by microRNAs. Numerous reports have shown a direct role of microRNAs in the modulation of angiogenesis in gynecological cancer, via targeting pro-angiogenic factors and signaling pathways. Understanding the molecular mechanism involved in the regulation of angiogenesis by microRNAs may lead to new treatment options. Recently the regulatory role of some long non-coding RNAs in gynecological cancer has also been explored, but the information on this function is more limited. The aim of this article is to explore the pathways responsible for angiogenesis, and to what extent ncRNAs may be employed as biomarkers or therapeutic targets in gynecological cancer.

CEA, CA 15-3, and miRNA expression as potential biomarkers in canine mammary tumors

The most often detected tumor in intact bitches is mammary tumors and represents a significant clinical problem throughout the world. Mammary neoplasms in canine have heterogeneous morphology, so the choice of the most appropriate biomarker is the biggest challenge in CMT detection. We performed a retrospective analysis and evaluated the canine cancer antigens and miRNA expression profiles as potential biomarkers. Sixty dogs based on histological examination divided into three groups, viz., dogs with a benign mammary tumor, malignant mammary tumor, and control/healthy. The CA 15-3 was found more sensitive than CEA but detection of both will increase sensitivity. miR-21 expression differed significantly in all three groups. miR-29b expression differed significantly between the control and benign group and control and malignant group. The miR-21 overexpression and miR-29b downregulation with CMT are associated with clinical stage and can be used as non-invasive diagnostic and prognostic biomarkers. Hence, evaluation of CA 15-3 along with CEA would be a non-invasive technique for detecting canine mammary tumors. Evaluation of deregulated circulating miR-21 could be a valuable prognostic marker for early detection of mammary tumors in canines while miR-29b can add sensitivity in the detection of the canine mammary tumors if evaluated with miR-21.

Targeting BRD9 for Cancer Treatment: A New Strategy

Bromodomain-containing protein 9 (BRD9) is a newly identified subunit of the non-canonical barrier-to-autointegration factor (ncBAF) complex and a member of the bromodomain family IV. Studies have confirmed that BRD9 plays an oncogenic role in multiple cancer types, by regulating tumor cell growth. The tumor biological functions of BRD9 are mainly due to epigenetic modification mediated by its bromodomain. The bromodomain recruits the ncBAF complex to the promoter to regulate gene transcription. This review summarizes the potential mechanisms of action of BRD9 in carcinogenesis and the emerging strategies for targeting BRD9 for cancer therapeutics. Although the therapeutic potential of BRD9 has been exploited to some extent, research on the detailed biological mechanisms of BRD9 is still in its infancy. Therefore, targeting BRD9 to study its biological roles will be an attractive tool for cancer diagnosis and treatment, but it remains a great challenge.

Preserving immune homeostasis with A20

A20/TNFAIP3 is a TNF induced gene that plays a profound role in preserving cellular and organismal homeostasis (Lee, et al., 2000; Opipari etal., 1990). This protein has been linked to multiple human diseases via genetic, epigenetic, and an emerging series of patients with mono-allelic coding mutations. Diverse cellular functions of this pleiotropically expressed protein include immune-suppressive, anti-inflammatory, and cell protective functions. The A20 protein regulates ubiquitin dependent cell signals; however, the biochemical mechanisms by which it performs these functions is surprisingly complex. Deciphering these cellular and biochemical facets of A20 dependent biology should greatly improve our understanding of murine and human disease pathophysiology as well as unveil new mechanisms of cell and tissue biology.

KRAS Mutation-Responsive miR-139-5p inhibits Colorectal Cancer Progression and is repressed by Wnt Signaling

Introduction: Colorectal cancer (CRC) frequently harbors KRAS mutations that result in chemoresistance and metastasis. MicroRNAs (miRNAs) are usually dysregulated and play important regulatory roles in tumor progression. However, the KRAS mutation-responsive miRNA profile in CRC remains uninvestigated. Methods: miR-139-5p was identified and evaluated by small RNA sequencing, qRT-PCR and in situ hybridization. The roles of miR-139-5p in CRC cells with and without KRAS mutation were determined by Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry and transwell assays in vitro and by tumorigenesis and metastasis assays in vivo. Microarrays followed by bioinformatic analyses, luciferase reporter assays and Western blotting were applied for mechanistic studies. Results: miR-139-5p was significantly downregulated in KRAS-mutated CRC cells and tissues compared with their wild-type counterparts. Low miR-139-5p expression was associated with aggressive phenotypes and poor prognosis in CRC patients. miR-139-5p overexpression inhibited CRC cell proliferation, migration and invasion in vitro, sensitized tumors to chemotherapy, and impaired tumor growth and metastasis in vivo. Transcriptomic profiling identified multiple modulators in the Ras (JUN and FOS) and Wnt (CTNNB1 and DVL1) signaling pathways and the epithelial-to-mesenchymal transition (EMT) process (ZEB1) as direct targets of miR-139-5p, and inverse correlations were confirmed in CRC clinical tissues. Aberrantly activated Wnt signaling in KRAS-mutant cells was demonstrated to transcriptionally repress miR-139-5p through TCF4, forming a miR-139-5p/Wnt signaling double-negative feedback loop. Conclusions: We identified miR-139-5p as a KRAS-responsive miRNA and demonstrated its involvement in CRC progression. KRAS mutation disrupted the miR-139-5p/Wnt signaling reciprocal negative feedback mechanism, which might cause miR-139-5p downregulation and derepression of oncogenic signaling pathways and EMT. These results reveal a transcriptional regulatory mode of KRAS-driven malignant transformation and highlight miR-139-5p as a novel regulator of crosstalk between the Ras and Wnt signaling pathways in CRC.

The genomic landscape of undifferentiated embryonal sarcoma of the liver is typified by C19MC structural rearrangement and overexpression combined with TP53 mutation or loss

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare and aggressive malignancy. Though the molecular underpinnings of this cancer have been largely unexplored, recurrent chromosomal breakpoints affecting a noncoding region on chr19q13, which includes the chromosome 19 microRNA cluster (C19MC), have been reported in several cases. We performed comprehensive molecular profiling on samples from 14 patients diagnosed with UESL. Congruent with prior reports, we identified structural variants in chr19q13 in 10 of 13 evaluable tumors. From whole transcriptome sequencing, we observed striking expressional activity of the entire C19MC region. Concordantly, in 7 of 7 samples undergoing miRNAseq, we observed hyperexpression of the miRNAs within this cluster to levels >100 fold compared to matched normal tissue or a non-C19MC amplified cancer cell line. Concurrent TP53 mutation or copy number loss was identified in all evaluable tumors with evidence of C19MC overexpression. We find that C19MC miRNAs exhibit significant negative correlation to TP53 regulatory miRNAs and K-Ras regulatory miRNAs. Using RNA-seq we identified that pathways relevant to cellular differentiation as well as mRNA translation machinery are transcriptionally enriched in UESL. In summary, utilizing a combination of next-generation sequencing and high-density arrays we identify the combination of C19MC hyperexpression via chromosomal structural event with TP53 mutation or loss as highly recurrent genomic features of UESL.

A20 at the Crossroads of Cell Death, Inflammation, and Autoimmunity

A20 is a potent anti-inflammatory protein, acting by inhibiting nuclear factor κB (NF-κB) signaling and inflammatory gene expression and/or by preventing cell death. Mutations in the A20/TNFAIP3 gene have been associated with a plethora of inflammatory and autoimmune pathologies in humans and in mice. Although the anti-inflammatory role of A20 is well accepted, fundamental mechanistic questions regarding its mode of action remain unclear. Here, we review new findings that further clarify the molecular and cellular mechanisms by which A20 controls inflammatory signaling and cell death, and discuss new evidence for its involvement in inflammatory and autoimmune disease development.

miR-29b Reverses T helper 1 cells/T helper 2 cells Imbalance and Alleviates Airway Eosinophils Recruitment in OVA-Induced Murine Asthma by Targeting Inducible Co-Stimulator

Asthma is a complex chronic disease and the pathogenesis is still not entirely clear. In this study, we aimed to clarify the role and mechanism of miR-29b in the development of asthma. We observed that miR-29b levels were decreased in the lung and spleen of OVA-induced asthmatic mice. Reverse transcription-quantitative polymerase chain reaction and flow cytometry demonstrated that the inducible co-stimulator (ICOS) expression at mRNA and protein levels was elevated in the lung of asthmatic mice, and miR-29b expression in the lung of asthmatic mice was negatively associated with ICOS mRNA levels by Pearson Correlation analysis. Additional, flow cytometry showed that the percentage of CD4+ICOS+ T cells in the lung and spleen was regulated by miR-29b, and dual luciferase reporter assay confirmed ICOS was a target gene of miR-29b. Furthermore, miR-29b overexpression in asthmatic mice was induced with miR-29b agomir by intranasal administration; miR-29b alleviated total inflammatory cell infiltration and CCL24 levels, decreased IL-5 levels in bronchoalveolar lavage fluid and serum, and upregulated IFN-γ expression in serum. This study demonstrates that miR-29b targets ICOS, thereby reverses the imbalance of T helper 1 cells (Th1)/Th2 responses and decreases eosinophils recruitment in the airway, which are key features of allergic airway inflammation. Therefore, miR-29b might be an attractive candidate target for asthma treatment.

miR-29b-3p promotes progression of MDA-MB-231 triple-negative breast cancer cells through downregulating TRAF3

BACKGROUND

Breast cancer is the second common malignant cancer among females worldwide. Accumulating studies have indicated that deregulation of miRNA expression in breast cancer will contribute to tumorigenesis and form different cancer subtypes. However, the reported studies on miR-29b-3p-regulated breast cancer are limited so far. Herein, we investigated the role and mechanism of miR-29b-3p in the triple negative breast cancer cell line MDA-MB-231.

METHODS

The relative miR-29b-3p expression in different breast cancer cell lines were determined by qRT-PCR. CCK8 and colony formation assay were used to determine the influence of miR-29b-3p on cell proliferation. Migration assay and invasion assay were performed for cell migration and invasion respectively. To study the cell integrity immunofluorescence was performed. TUNEL assay, flow cytometry assay, hoechst staining and western blot were conducted to determine the influence of miR-29b-3p inhibitor on cell apoptosis. TRAF3 was found to be the target gene of miR-29b-3p using bioinformatics predictions. Dual-luciferase assay was performed to determine the relative luciferase activity in NC, miR-29b-3p mimic, miR-29b-3p inhibitor with TRAF3 3'-UTR wt or TRAF3 3'-UTR mt reporter plasmids. The proteins expression of NF-κB signaling pathway in MDA-MB-231 after transfection with NC, miR-29b-3p mimic, miR-29b-3p inhibitor were determined by western blot.

RESULTS

The miR-29b-3p expression was significantly increased in MDA-MB-231 compare with MCF-10A. miR-29b-3p inhibitor reduced the cell viability of MDA-MB-231 and inhibited cell migration and invasion. Cell cytoskeleton integrity destroyed after miR-29b-3p inhibitor treatment. Furthermore, we identified the mechanism and found miR-29b-3p targets the TRAF3 and activates NF-κB signaling pathway.

CONCLUSIONS

From the above studies, our results indicated that miR-29b-3p acts as a promoter for the development of MDA-MB-231.

MicroRNA-29b-3p reduces intestinal ischaemia/reperfusion injury via targeting of TNF receptor-associated factor 3

BACKGROUND AND PURPOSE

The microRNA miR-29b-3p shows important roles in regulating apoptosis and inflammation. However, its effects on intestinal ischaemia/reperfusion (II/R) injury have not been reported. Here we have investigated the functions of miR-29b-3p on II/R injury on order to find drug targets to treat the injury.

EXPERIMENTAL APPROACH

Two models - in vitro hypoxia/reoxygenation (H/R) of IEC-6 cells; in vivo, II/R injury in C57BL/6 mice were used. Western blotting and dual-luciferase reporter assays were used and mimic and siRNA transfection tests were applied to assess the effects of miR-29b-3p on II/R injury via targeting TNF receptor-associated factor 3 (TRAF3).

KEY RESULTS

The H/R procedure decreased cell viability and promoted inflammation and apoptosis in IEC-6 cells, and the II/R procedure also promoted intestinal inflammation and apoptosis in mice. Expression levels of miR-29b-3p were decreased in H/R-induced cells and II/R-induced intestinal tissues of mice compared with control group or sham group, which directly targeted TRAF3. Decreased miR-29b-3p level markedly increased TRAF3 expression via activating TGF-α-activated kinase 1 phosphorylation, increasing NF-κB (p65) levels to promote inflammation, up-regulating Bcl2-associated X expression, and down-regulating Bcl-2 expression to trigger apoptosis. In addition, the miR-29b-3p mimetic and TRAF3 siRNA in IEC-6 cells markedly suppressed apoptosis and inflammation to alleviate II/R injury via inhibiting TRAF3 signallimg.

CONCLUSIONS AND IMPLICATIONS

The miR-29b-3p played a critical role in II/R injury, via targeting TRAF3, which should be considered as a significant drug target to treat the disease.

Neuroplastin-β mediates S100A8/A9-induced lung cancer disseminative progression

Compiling evidence indicates an unusual role of extracellular S100A8/A9 in cancer metastasis. S100A8/A9 secreted from either cancer cells or normal cells including epithelial and inflammatory cells stimulates cancer cells through S100A8/A9 sensor receptors in an autocrine or paracrine manner, leading to cancer cell metastatic progression. We previously reported a novel S100A8/A9 receptor, neuroplastin-β (NPTNβ), which plays a critical role in atopic dermatitis when it is highly activated in keratinocytes by an excess amount of extracellular S100A8/A9 in the inflammatory skin lesion. Interestingly, our expression profiling of NPTNβ showed significantly high expression levels in lung cancer cell lines in a consistent manner. We hence aimed to determine the significance of NPTNβ as an S100A8/A9 receptor in lung cancer. Our results showed that NPTNβ has strong ability to induce cancer-related cellular events, including anchorage-independent growth, motility and invasiveness, in lung cancer cells in response to extracellular S100A8/A9, eventually leading to the expression of a cancer disseminative phenotype in lung tissue in vivo. Mechanistic investigation revealed that binding of S100A8/A9 to NPTNβ mediates activation of NFIA and NFIB and following SPDEF transcription factors through orchestrated upstream signals from TRAF2 and RAS, which is linked to anchorage-independent growth, motility and invasiveness. Overall, our results indicate the importance of the S100A8/A9-NPTNβ axis in lung cancer disseminative progression and reveal a pivotal role of its newly identified downstream signaling, TRAF2/RAS-NFIA/NFIB-SPDEF, in linking to the aggressive development of lung cancers.

miR-140-3p functions as a tumor suppressor in squamous cell lung cancer by regulating BRD9

Squamous cell lung cancer (SqCLC) is among the most malignant lung cancers worldwide, lacking biomarkers for diagnostic and targets for treatment. In this study, we observed that miR-140-3p was expressed at low levels both in SqCLC cell lines and patient samples, while overexpression of miR-140-3p dramatically reduced the cell proliferation and invasion in SqCLC cells and Patient derived xenograft (PDX) models. Our further investigation indicated miR-140-3p negatively affected the tumorigenesis of SqCLC by down-regulating the expression of BRD9, an oncogene in SqCLC. Inhibition of BRD9 repressed SqCLC tumorigenesis by regulating c-myc expression. Meanwhile, BRD9 expression is up-regulated and negatively correlated with miR-140-3p in clinical samples; a meta-analysis of survival data indicates that SqCLC patients with high levels of BRD9 in their tumors have a worse prognosis. Collectively, our study suggests the prognostic and therapeutic roles of miR-140-3p and BRD9 axis in squamous cell lung cancer.

Inhibition of miR-24 suppresses malignancy of human non-small cell lung cancer cells by targeting WWOX in vitro and in vivo

Background

We investigated the effect of micro‐RNA 24 (miR‐24) and WWOX on non‐small cell lung cancer (NSCLC) cell proliferation and migration in vitro and in vivo.

Methods

We performed bioinformatics analysis and 3′ untranslated region luciferase assay to investigate the direct target of miR‐24. Proliferation, apoptosis, and transwell invasion assays were employed to evaluate the effect of WWOX overexpression with pcDNA3‐WWOX and knocking down miR‐24 with miR‐24 small interfering RNA. Quantitative real‐time PCR, Western blot, and immunohistochemistry were also used to investigate miR‐24 and c‐Kit expression, and apoptosis and invasion‐related proteins. Finally, we constructed a tumor xenograft model in nude mice to confirm the effect of miR‐24 on NSCLC cell proliferation in vivo.

Results

According to our experimental data, miR‐24 inhibition could induce apoptosis by activating caspase 3 and suppress the viability and proliferation of NSCLC cells in vitro and in vivo. MiR‐24 downregulation could reduce the invasive ability of NSCLC cells by downregulating MMP9. WWOX was identified as a functional target of miR‐24. WWOX overexpression generated the same effect with antagonizing miR‐24, while blocking WWOX counteracted the tumor suppressive effect caused by miR‐24 inhibition. MiR‐24 may function as an oncogene and play an important role in the cell growth and migration of NSCLC.

Conclusions

Our findings enhance understanding of the miR‐24 regulatory network and the molecular mechanism that underlies the oncogenesis and development of NSCLC. Suppressing the effect of miR‐24 on cancer cells using a miR‐24 inhibitor may be an attractive therapeutic strategy against NSCLC.

[Overpression of miR-29b suppresses the proliferation and induces apoptosis of cholangiocarcinoma cells]

OBJECTIVE

To investigate the expression of miR-29b in cholangiocarcinoma and explore its effects on cell proliferation and apoptosis of cholangiocarcinoma cells.

METHODS

Real-time PCR was used to detect the expression of miR-29b in cholangiocarcinoma cells line QBC939 and cholangiocarcinoma tissues. The lentiviral vector LV-hsa-miR-29b and blank vector were constructed to infect QBC939 cells. MTT assay and cell clone formation assay were performed to assess the changes in the cell proliferation and clone formation, respectively; flow cytometry was employed to evaluate the effect of miR-29b overexpression on cell cycle and apoptosis.

RESULTS

The expression of miR-29b was significantly down-regulated in QBC939 cells and cholangiocarcinoma tissues as compared with H-69 cells and normal tissues (P < 0.01). Compared with the blank vector, the lentiviral vector LV-hsa-miR-29b caused significantly increased expression of miR-29b in QBC939 cells (P < 0.01), which exhibited suppressed cell proliferation and clone formation (P < 0.01 or 0.05), cell cycle arrest at the S phase (P < 0.05), and significantly increased cell apoptosis (P < 0.01).

CONCLUSIONS

As a tumor-suppressing miRNA, miR-29b is down-regulated in cholangiocarcinoma, and its overexpression can suppress the proliferation and induce apoptosis of cholangiocarcinoma cells.

mTOR mediates a mechanism of resistance to chemotherapy and defines a rational combination strategy to treat KRAS-mutant lung cancer

Oncogenic KRAS mutations comprise the largest subset of lung cancer defined by genetic alterations, but in the clinic no targeted therapies are available that effectively control mutational KRAS activation. Consequently, patients with KRAS-driven tumors are routinely treated with cytotoxic chemotherapy, which is often transiently effective owing to development of drug resistance. In this study, we show that hyperactivated mammalian target of rapamycin (mTOR) pathway is a characteristic hallmark of KRAS-mutant lung adenocarcinoma after chemotherapy treatment, and that KRAS-mutant lung cancer cells rely on persistent mTOR signaling to resist chemotherapeutic drugs. Coherently, mTOR inhibition circumvents the refractory phenotype and restores sensitivity of resistant KRAS-mutant lung cancer cells to chemotherapy. Importantly, drug combinations of clinically approved mTOR inhibitors and chemotherapy drugs synergize in inhibiting cell proliferation of KRAS-mutant cancer cells in vitro and in vivo, and the efficacy of this combination treatment correlates with the magnitude of mTOR activity induced by chemotherapy alone. These results pinpoint mTOR as a mechanism of resistance to chemotherapy in KRAS-mutant lung cancer and validate a rational and readily translatable strategy that combines mTOR inhibitors with standard chemotherapy to treat KRAS-mutant adenocarcinoma, the most common and deadliest lung cancer subset.

KRAS-specific Amino Acid Substitutions are Associated With Different Responses to Chemotherapy in Advanced Non-small-cell Lung Cancer

BACKGROUND

Emerging data highlight different clinical behaviors according to KRAS amino acid substitutions (AASs) in patients with non-small-cell lung cancer (NSCLC). We aimed to evaluate whether different KRAS AASs were associated with different responses to chemotherapy.

PATIENTS AND METHODS

We retrospectively reviewed data from 1190 patients with KRAS mutations who underwent first-line platinum-based chemotherapy for stage IV NSCLC. The response to different chemotherapy regimens was evaluated using the Response Evaluation Criteria In Solid Tumors criteria (v 1.1). Overall survival and time to progression (TTP) were secondary endpoints.

RESULTS

Taxane was associated with the best response in the entire cohort (odds ratio, 2.52; 95% confidence interval [CI], 1.82-3.48; P < .001), especially in G12V patients (odds ratio, 2.15; 95% CI, 1.05-4.41; P = .036). Taxane was associated with improved TTP in the entire cohort (hazard ratio [HR], 0.31; 95% CI, 0.26-0.38; P < .001), especially in G13D patients (HR, 0.47; 95% CI, 0.22-1.01; P = .054). Pemetrexed was associated with the worst TTP in the entire cohort, particularly in G12V patients, who had the worst response rates (HR, 0.55; 95% CI, 0.30-0.99; P = .049). No impact on overall survival was observed according to different chemotherapy regimens and AASs.

CONCLUSION

KRAS-specific AAS appears to induce different responses to chemotherapy regimens after first-line platinum-based chemotherapy in advanced NSCLC.

RMP promotes epithelial-mesenchymal transition through NF-κB/CSN2/Snail pathway in hepatocellular carcinoma

Epithelial-mesenchymal transition (EMT) is a significant risk factor for metastasis in hepatocellular carcinoma (HCC) patients and with poor prognosis. In this study, we demonstrate the key role of RPB5-mediating protein (RMP) in EMT of HCC cells and the mechanism by which RMP promote EMT. RMP increases migration, invasion, and the progress of EMT of HCC cells, which facilitates the accumulation of Snail, a transcriptional repressor involved in EMT initiation. NF-κB is activated by RMP, which directly promotes the expression of COP9 signalosome 2 (CSN2) to repress the degradation of Snail. Pulmonary metastases mouse model demonstrates that RMP induces metastasis in vivo. Immunohistochemical analysis of human HCC tissues confirms the correlation of RMP with the expression of E-cadherin, p65, CSN2 and Snail in vivo. Collectively, these findings indicate that RMP promotes EMT and HCC metastasis through NF-κB/CSN2/Snail pathway. These results suggest that RMP and p65 may serve as potential candidates of the targets in the treatment of metastatic HCC.

Targeting liver sinusoidal endothelial cells with miR-20a-loaded nanoparticles reduces murine colon cancer metastasis to the liver

Phenotypic transformation of liver sinusoidal endothelial cells is one of the most important stages of liver metastasis progression. The miRNA effects on liver sinusoidal endothelial cells during liver metastasis have not yet been studied. Herein, whole genome analysis of miRNA expression in these cells during colorectal liver metastasis revealed repressed expression of microRNA-20a. Importantly, downregulation of miR-20a occurs in parallel with upregulation of its known protein targets. To restore normal miR-20a levels in liver sinusoidal endothelial cells, we developed chondroitin sulfate-sorbitan ester nanoparticles conjugated with miR-20a in a delivery system that specifically targets liver sinusoidal endothelial cells. The restoration of normal mir-20a levels in these cells induced downregulation of the expression of its protein targets, and this also resulted in a reduction of in vitro LSEC migration and a reduction of in vivo activation and tumor-infiltrating capacity and ability of the tumor decreased by ∼80% in a murine liver metastasis model.

Increased expression of miR-641 contributes to erlotinib resistance in non-small-cell lung cancer cells by targeting NF1

Epidermal growth receptor (EGFR)‐targeted tyrosine kinase inhibitors (TKIs) have emerged as first‐line drugs for advanced non‐small‐cell lung cancer (NSCLC) patients with EFGR mutations. However, most patients with NSCLC show acquired resistance to EGFR‐TKIs, and low expression of NF1 is a mechanism of EGFR‐TKI resistance in lung cancer. However, the mechanism by which NF1 is downregulated in EGFR‐TKI‐resistant NSCLC is unclear. Here, we found the increased expression of miR‐641 in NSCLC cells and human NSCLC samples with resistance to TKI compared to those with sensitive to TKI. In addition, our in vitro experiments show that overexpression of miR‐641 induces TKI resistance in NSCLC cells. Furthermore, we identified that miR‐641 activates ERK signaling by direct targeting of neurofibromatosis 1 (NF1) in NSCLC cells. Our data show that overexpression of NF1 or silencing of ERK can block miR‐641‐induced resistance of NSCLC cells to erlotinib treatment. Importantly, our animal experiments show that combination of miR‐641 inhibition and erlotinib treatment can significantly inhibit erlotinib‐resistant NSCLC growth, inhibit proliferation and induce apoptosis compared to single‐drug treatment. Our findings suggest that increased expression of miR‐641 significantly contributes to erlotinib resistance development in NSCLC cells through activating ERK signaling by targeting NF1 and that inhibition of miR‐641 may reverse acquired resistance of NSCLC cells to erlotinib treatment.

miR-19b enhances proliferation and apoptosis resistance via the EGFR signaling pathway by targeting PP2A and BIM in non-small cell lung cancer

Background

Epidermal growth factor receptor (EGFR) mutations enable constitutive active downstream signaling of PI3K/AKT, KRAS/ERK and JAK/STAT pathways, and promote tumor progression by inducing uncontrolled proliferation, evasion of apoptosis and migration of non-small cell lung cancer (NSCLC). In addition, such EGFR mutations increase the susceptibility of patients with NSCLC to tyrosine kinase inhibitor (TKI) therapy, but treated patients will invariably relapse with resistant disease. A global understanding of underlying molecular mechanisms of EGFR signaling may improve the management of NSCLC patients.

Methods

microarray analysis was performed to identify PI3K/AKT-regulated miRNAs. Phosphoproteomic analysis and cell based assays were performed using NSCLC cell lines lentivirally transduced with anti-miR or miR overexpressing constructs.

Results

Here, we show that 17 miRNAs including members of the miR-17~ 92 cluster are dysregulated following PI3K/AKT inhibition of EGFR mutant NSCLC cells. Bioinformatics analysis revealed that dysregulated miRNAs act in a concerted manner to enhance the activity of the EGFR signaling pathway. These findings were closely mirrored by attenuation of miR-17~ 92 family member miR-19b in NSCLC cell lines which resulted in reduced phosphorylation of ERK, AKT and STAT and effector proteins in EGFR mutant NSCLC cells. Consistent with this finding, cell cycle progression, clonogenic growth and migration were reduced and apoptosis was enhanced. Co-treatment of NSCLC cells with the tyrosine kinase inhibitor (TKI) gefitinib and anti-miR-19b construct reduced migration and clonogenic growth in a synergistic manner suggesting that EGFR and miR-19b act together to control oncogenic processes. Serine/threonine phosphatase PP2A subunit PPP2R5E and BCL2L11 encoding BIM were identified as major targets of miR-19b by target validation assays. Consistent with this finding, PP2A activity was strongly enhanced in NSCLC transduced with anti-miR-19b construct, but not in cells co-transduced with anti-miR-19b and shPPP2R5E, suggesting that PPP2R5E is a major constituent of the PP2A complex. Accordingly, enhanced proliferation by miR-19b was due to targeting PPP2R5E. In contrast, apoptosis resistance was mainly due to targeting BCL2L11.

Conclusion

Our results provide insight into the importance of targeting PPP2R5E and BCL2L11 by miR-19b in oncogenic processes of NSCLC. Attenuation of miR-19b expression could potentially be exploited in adjuvant therapy of EGFR mutant NSCLC.

Electronic supplementary material

The online version of this article (10.1186/s12943-018-0781-5) contains supplementary material, which is available to authorized users.

Overexpression of MicroRNA-29b Decreases Expression of DNA Methyltransferases and Improves Quality of the Blastocysts Derived from Somatic Cell Nuclear Transfer in Cattle

MicroRNA (miR)-29b plays a crucial role during somatic cell reprogramming. The aim of the current study was to explore the effects of miR-29b on the developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos, as well as the underlying mechanisms of action. The expression level of miR-29b was lower in bovine SCNT embryos at the pronuclear, 8-cell, and blastocyst stages compared with in vitro fertilized embryos. In addition, miR-29b regulates the expression of DNA methyltransferases (Dnmt3a/3b and Dnmt1) in bovine SCNT embryos. We further investigated SCNT embryo developmental competence and found that miR-29b overexpression during bovine SCNT embryonic development does not improve developmental potency and downregulation inhibits developmental potency. Nevertheless, the quality of bovine SCNT embryos at the blastocyst stage improved significantly. The expression of pluripotency factors and cellular proliferation were significantly higher in blastocysts from the miR-29b overexpression group than the control and downregulation groups. In addition, outgrowth potential in blastocysts after miR-29b overexpression was also significantly greater in the miR-29b overexpression group than in the control and downregulation groups. Taken together, these results demonstrated that miR-29b plays an important role in bovine SCNT embryo development.

MiR-29b/TET1/ZEB2 signaling axis regulates metastatic properties and epithelial-mesenchymal transition in breast cancer cells

MiR-29b has been reported to be both a suppressor and a promoter in breast cancer (BC) cells proliferation and metastasis. Significant efforts have been made to explain the seemingly contradictory effects of miR-29b on BC, but no answer has yet been clearly verified. In this study, we overexpressed and knocked down miR-29b in BC cell lines, modulated expression of its downstream target gene TET1 and downregulated a downstream target gene of TET1, ZEB2, to explore the regulatory mechanism of miR-29b in BC cell proliferation, migration and epithelial-mesenchymal transition (EMT). Our results showed lower expression of miR-29b in BC samples and cell lines. Functional assays showed that miR-29b overexpression resulted in a higher cell proliferation, greater colony formation, higher migration rate and EMT. A dual luciferase assay identified TET1 as a direct target of miR-29b. As the promoting effects of miR-29b in the proliferation and metastasis of MDA-MB-231 and MCF-7, knockdown of TET1 also led to increased proliferation, colony formation, invasion and EMT. Further, we found that TET1 bound to the promoter of ZEB2, and siTET1 enhanced ZEB2 expression. Disruption of ZEB2 expression inhibited BC cells proliferation, colony formation and invasion. Our results establish the miR-29b/TET1/ZEB2 pathway in BC cell proliferation, migration and provide a theoretical basis for further research on the molecular mechanisms and new clinical treatments for BC.

KRAS-driven miR-29b expression is required for tumor suppressor gene silencing

KRAS activation drives DNA methylation and silencing of specific tumor suppressor genes (TSGs). We previously showed that the ERK pathway induces transcriptional repression of TET1, which results in conversion of TSG promoters from a hydroxymethylated, active state to a hypermethylated and silenced state. Here we identified miR-29b as a KRAS-induced molecule that represses TET1 expression. In KRAS-transformed cells, ectopic miR-29b inhibition restores expression of TET1, thereby reactivating TSGs by reducing methylation and restoring hydroxymethylation. Mining gene expression data of lung cancer cell lines identified additional TSGs suppressed by KRAS signaling whose expression was restored by inhibition of miR-29b and re-expression of TET1. Because KRAS changes TSG promoters from hydroxymethylated to hypermethylated with miR-29b-dependent silencing of TET1, we demonstrate a model in which DNMT1 is present on target promoters prior to KRAS transformation. In addition, we propose miR-29b as a potential circulating biomarker and target for rational treatment of specific malignancies.

Significance of microRNAs in Androgen Signaling and Prostate Cancer Progression

The androgen receptor (AR) plays important roles in prostate cancer development and prostate tumor growth. After binding to androgens, AR functions as a nuclear receptor and translocates to the nucleus to bind to specific AR-binding sites (ARBSs). AR regulates epigenetic factor recruitments to activate its downstream signaling. Although androgen deprivation therapy (ADT) is initially useful for prostate cancer patients, most patients eventually show resistance with hormone-refractory prostate cancers (HRPCs) or castration-resistant prostate cancers (CRPCs). Thus, new therapeutic strategies targeting HRPCs/CRPCs should be very important for clinical medicine as well as prostate cancer biology. Past studies have shown that mechanisms such as AR overexpression, hypersensitivity, variants and reprograming are responsible for developing HRPCs/CRPCs. These findings suggest that AR target genes will be major key factors. In this review article, we focus mainly on the androgen-regulated microRNAs (miRNAs) to summarize the contribution of miRNA-mediated pathways for prostate cancer progression.

Treating KRAS-mutant NSCLC: latest evidence and clinical consequences

KRAS mutations represent one of the most prevalent oncogenic driver mutations in non-small cell lung cancer (NSCLC). For many years we have unsuccessfully addressed KRAS mutation as a unique disease. The recent widespread use of comprehensive genomic profiling has identified different subgroups with prognostic implications. Moreover, recent data recognizing the distinct biology and therapeutic vulnerabilities of different KRAS subgroups have allowed us to explore different treatment approaches. Small molecules that selectively inhibit KRAS G12C or use of immune checkpoint inhibitors based on co-mutation status are some examples which anticipate that personalized treatment for this challenging disease is finally on the horizon.

MiR-125b Increases Nasopharyngeal Carcinoma Radioresistance by Targeting A20/NF-κB Signaling Pathway

Radioresistance poses a major challenge in nasopharyngeal carcinoma (NPC) treatment, but little is known about how miRNA regulates this phenomenon. In this study, we investigated the function and mechanism of miR-125b in NPC radioresistance, one of upregulated miRNAs in the radioresistant NPC cells identified by our previous microarray analysis. We observed that miR-125b was frequently upregulated in the radioresistant NPCs, and its increment was significantly correlated with NPC radioresistance, and was an independent predictor for poor patient survival. In vitro radioresponse assays showed that miR-125b inhibitor decreased, whereas miR-125b mimic increased NPC cell radioresistance. In a mouse model, therapeutic administration of miR-125b antagomir dramatically sensitized NPC xenografts to irradiation. Mechanistically, we confirmed that A20 was a direct target of miR-125b and found that miR-125b regulated NPC cell radioresponse by targeting A20/NF-κB signaling. With a combination of loss-of-function and gain-of-function approaches, we further showed that A20 overexpression decreased while A20 knockdown increased NPC cell radioresistance both in vitro and in vivo Moreover, A20 was significantly downregulated while p-p65 (RelA) significantly upregulated in the radioresistant NPCs relative to radiosensitive NPCs, and miR-125b expression level was negatively associated with A20 expression level, whereas positively associated with p-p65 (RelA) level. Our data demonstrate that miR-125b and A20 are critical regulators of NPC radioresponse, and high miR-125b expression enhances NPC radioresistance through targeting A20 and then activating the NF-κB signaling pathway, highlighting the therapeutic potential of the miR-125b/A20/NF-κB axis in clinical NPC radiosensitization. Mol Cancer Ther; 16(10); 2094-106. ©2017 AACR.

MiR-125b regulates proliferation and apoptosis of nasopharyngeal carcinoma by targeting A20/NF-κB signaling pathway

MiR-125b is aberrantly expressed and has a role in the various types of tumors. However, the role and mechanism of miR-125b in nasopharyngeal carcinoma (NPC) are unclear. In this study, we investigated the role and mechanism of miR-125b in NPC. We observed that miR-125b was significantly upregulated in the NPC tissues relative to normal nasopharyngeal mucosa (NNM), and its increment was correlated with poor patient survival, and was an independent predictor for reduced patient survival; miR-125b promoted NPC cell proliferation and inhibited NPC cell apoptosis; in a mouse model, administration of miR-125b antagomir significantly reduced the growth of NPC xenograft tumors. Mechanistically, we confirmed that A20 was a direct target of miR-125b, and found that activation of nuclear factor κB (NF-κB) signaling pathway by A20 mediated miR-125b-promoting NPC cell proliferation and -inhibiting NPC cell apoptosis. With a combination of loss-of-function and gain-of-function approaches, we further showed that A20 inhibited NPC cell proliferation, induced NPC cell apoptosis, and reduced the growth of NPC xenograft tumors. Moreover, A20 was significantly downregulated, whereas p-p65(RelA) was significantly upregulated in the NPC tissues relative to normal nasopharyngeal mucosa, and miR-125b level was negatively associated with A20 level, whereas positively associated with p-p65 level. Our data demonstrate that miR-125b regulates NPC cell proliferation and apoptosis by targeting A20/NF-κB signaling pathway, and miR-125b acts as oncogene, whereas A20 functions as tumor suppressor in NPC, highlighting the therapeutic potential of miR-125b/A20/NF-κB signaling axis in the NPC.

MiRNA-29b suppresses tumor growth through simultaneously inhibiting angiogenesis and tumorigenesis by targeting Akt3

The traditional anti-angiogenic cancer therapy could trigger hypoxia induced factor (HIF) response, leading to "reactive resistance" to chemotherapy. Simultaneously inhibiting both angiogenesis and tumorigenesis would be ideal to overcome this limitation. MicroRNAs (miRNAs) are increasingly explored as new agents for cancer therapy. In the present study, we identified a microRNA (miR-29b) with the ability of simultaneously inhibiting angiogenesis and tumorigenesis. Ectopic expression of miR-29b inhibits HUVECs formed three-dimensional capillary-like tubular structures, tumor cell proliferation, migration and tumor formation. Systemic administration of miR-29b potently suppressed tumor vascularization and cancer cell activity in vivo, resulting in dramatic suppression of tumor growth without toxicity. Moreover, we demonstrated the role of miR-29b in anti-angiogenesis and anti-tumorigenesis is through targeting Akt3 and inducing VEGF and C-myc arrest in breast cancer cells. These findings indicate that this single miRNA could be used as an efficient anti-cancer therapeutic agent to address a critical challenge in cancer therapy.

Computational Analysis of Specific MicroRNA Biomarkers for Noninvasive Early Cancer Detection

Cancer is a complex disease residing in various tissues of human body, accompanied with many abnormalities and mutations in genomes, transcriptome, and epigenome. Early detection plays a crucial role in extending survival time of all major cancer types. Recent advances in microarray and sequencing techniques have given more support to identifying effective biomarkers for early detection of cancer. MicroRNAs (miRNAs) are more and more frequently used as candidates for biomarkers in cancer related studies due to their regulation of target gene expression. In this paper, the comparative analysis is used to discover miRNA expression patterns in cancer versus normal samples on early stage of eight prevalent cancer types. Our work focuses on the specific miRNAs biomarkers identification and function analysis. Several identified miRNA biomarkers in this paper are matched well with those reported in existing researches, and most of them could serve as potential candidate indicators for clinical early diagnosis applications.

MicroRNA-29b Inhibits Angiogenesis by Targeting VEGFA through the MAPK/ERK and PI3K/Akt Signaling Pathways in Endometrial Carcinoma

OBJECTIVE

The purpose of this study is to explore the effects of microRNA-29b (miR-29b) regulating MAPK/ERK and PI3K/Akt signaling pathways on angiogenesis in endometrial carcinoma (EC) by targeting VEGFA.

METHODS

Between February 2013 and April 2015, 126 EC patients admitted to the Second Affiliated Hospital of Nanchang University were randomly selected, with 126 EC tissues and the corresponding adjacent normal tissues collected after surgery. The human EC cell lines RL-95-2 and HEC-1-B and human endometrial cells were assigned to the normal group (human endometrial cells), the blank group (untransfected RL-95-2 or HEC-1-B cells), the pMIR-control group (RL-95-2 or HEC-1-B cells transfected with an empty vector), the pMIR-miR-29b group (RL-95-2 or HEC-1-B cells transfected with the miR-29b plasmid), LNA-control group (RL-95-2 or HEC-1-B cells transfected with an oligonucleotide inhibitors control), the LNA-miR-29b inhibitors group (RL-95-2 or HEC-1-B cells transfected with miRCURY LNATM miR-29b inhibitors), the LNA-miR-29b inhibitors + PD98059 group (RL-95-2 or HEC-1-B cells transfected with miRCURY LNATM miR-29b inhibitors and PD98059, an inhibitor of the MAPK/ERK signaling pathway) and the LNA-miR-29b inhibitors + wortmannin group (RL-95-2 or HEC-1-B cells transfected with miRCURY LNATM miR-29b inhibitors and wortmannin, an inhibitor of the PI3K/Akt signaling pathway). qRT-PCR and Western blotting were conducted to detect the miR-29b expression and the mRNA and protein expressions of VEGFA, ERK, Akt, mTOR and Bcl-2. Immunohistochemistry (IHC) was performed to determine the microvessel density (MVD) expression in the EC tissues, adjacent normal tissues and nude-mice.

RESULTS

Compared with the adjacent normal tissues, miR-29b expression was down-regulated, the mRNA and protein expressions of VEGFA, ERK, Akt, mTOR and Bcl-2 were up-regulated, and MVD expression was increased in the EC tissues. Compared with the normal group, miR-29b expression was down-regulated, while the mRNA and protein expressions of VEGFA, ERK, Akt, mTOR and Bcl-2 were up-regulated in the other groups. Compared with the blank, pMIR-control and LNA-control groups, miR-29b expression was increased, while mRNA and protein expressions of VEGFA, ERK, Akt, mTOR and Bcl-2 were decreased in the pMIR-miR-29b group. The LNA-miR-29b inhibitors group exhibited elevated miR-29b expression and decreased mRNA and protein expressions of VEGFA, ERK, Akt, mTOR and Bcl-2 (All P < 0.05). Additionally, miR-29b expression was reduced in the LNA-miR-29b inhibitors + PD98059 and LNA-miR-29b inhibitors + wortmannin groups. In comparison to the normal group, MVD expression was elevated in the other groups. Compared with the blank, pMIR-control, LNA-control, LNA-miR-29b inhibitors + PD98059 and LNA-miR-29b inhibitors + wortmannin groups, MVD expression was decreased in the pMIR-miR-29b group but increased in the LNA-miR-29b inhibitors group.

CONCLUSION

Our results indicate that miR-29b negatively modulates the MAPK/ERK and PI3K/Akt signaling pathways to inhibit angiogenesis in EC by targeting VEGFA.

MiR-488 inhibits proliferation and cisplatin sensibility in non-small-cell lung cancer (NSCLC) cells by activating the eIF3a-mediated NER signaling pathway

Our previous studied indicated that eukaryotic translation initiation factor 3a (eIF3a) increases the sensitive of platinum-based chemotherapy in lung cancer. MiRNAs play an important role in lung carcinogenesis and drug response. In this study, we aimed to identify potential endogenous miRNAs that inhibit eIF3a expression and determine their influence of this inhibition on cisplatin resistance. Using bioinformatics analysis prediction and confirmation with dual-luciferase reporter assays, we found that miRNA-488 inhibited eIF3a expression by directly binding to the 3’UTR of eIF3a. In addition, the overexpression of miRNA-488 inhibited cell migration and invasion in A549 cells, and also inhibited cell proliferation, cell cycle progression by elevated P27 expression. Compared to the parental cell line, A549/cisplatin (DDP) resistant cells exhibited a higher level of miRNA-488. Moreover, we found that miRNA-488 was associated with cisplatin resistance in three NSCLC cells (A549, H1299 and SK-MES-1). The mechanism of miRNA-488 induced cisplatin resistance was that miRNA-488 activated nucleotide excision repair (NER) by increasing the expression of Replication Protein A (RPA) 14 and Xeroderma pigmentosum group C (XPC). In conclusion, our results demonstrated that miRNA-488 is a tumor suppressor miRNA that acts by targeting eIF3a. Moreover, miRNA-488 also participates in eIF3a mediated cisplatin resistance in NSCLC cells.

Targeting MicroRNAs in Cancer Gene Therapy

MicroRNAs (miRNAs) are a kind of conserved small non-coding RNAs that participate in regulating gene expression by targeting multiple molecules. Early studies have shown that the expression of miRNAs changes significantly in different tumor tissues and cancer cell lines. It is well acknowledged that such variation is involved in almost all biological processes, including cell proliferation, mobility, survival and differentiation. Increasing experimental data indicate that miRNA dysregulation is a biomarker of several pathological conditions including cancer, and that miRNA can exert a causal role, as oncogenes or tumor suppressor genes, in different steps of the tumorigenic process. Anticancer therapies based on miRNAs are currently being developed with a goal to improve outcomes of cancer treatment. In our present study, we review the function of miRNAs in tumorigenesis and development, and discuss the latest clinical applications and strategies of therapy targeting miRNAs in cancer.

MicroRNA-targeted therapeutics for lung cancer treatment

INTRODUCTION

Lung cancer is one of the leading causes of cancer-related mortality worldwide. MicroRNAs (miRNAs) are endogenous non-coding small RNAs that repress the expression of a broad array of target genes. Many efforts have been made to therapeutically target miRNAs in cancer treatments using miRNA mimics and miRNA antagonists. Areas covered: This article summarizes the recent findings with the role of miRNAs in lung cancer, and discusses the potential and challenges of developing miRNA-targeted therapeutics in this dreadful disease. Expert opinion: The development of miRNA-targeted therapeutics has become an important anti-cancer strategy. Results from both preclinical and clinical trials of microRNA replacement therapy have shown some promise in cancer treatment. However, some obstacles, including drug delivery, specificity, off-target effect, toxicity mediation, immunological activation and dosage determination should be addressed. Several delivery strategies have been employed, including naked oligonucleotides, liposomes, aptamer-conjugates, nanoparticles and viral vectors. However, delivery remains a main challenge in miRNA-targeting therapeutics. Furthermore, immune-related serious adverse events are also a concern, which indicates the complexity of miRNA-based therapy in clinical settings.