Breast cancer metastasis suppressor 1 up-regulates miR-146, which suppresses breast cancer metastasis

MicroRNA-146b-5p/FDFT1 mediates cisplatin sensitivity in bladder cancer by redirecting cholesterol biosynthesis to the non-sterol branch

Chemotherapy against muscle-invasive bladder cancer is increasingly challenged by the prevalence of chemoresistance. The cholesterol biosynthesis pathway has garnered attention in studies of chemoresistance, but conflicting clinical and molecular findings necessitate a clearer understanding of its underlying mechanisms. Recently, we identified farnesyl-diphosphate farnesyltransferase 1 (FDFT1)-the first specific gene in this pathway-as a tumor suppressor and chemoresistance modulator. Raman spectroscopy revealed higher levels of FDFT1-related metabolites in chemotherapy-sensitive bladder cancer tissue compared to resistant tissue; however, this observation lacks mechanistic insight. FDFT1 expression was reduced in our cisplatin-resistant bladder cancer cells (T24R) compared to parental cisplatin-sensitive cells (T24). Using functional knockdown and ectopic overexpression in T24/T24R cells, we mechanistically demonstrate the pathway through which FDFT1 mediates cisplatin sensitivity in bladder cancer cells. Bioinformatics analysis and rescue experiments showed that microRNA-146b-5p directly targets and downregulates FDFT1, reducing the cisplatin sensitivity of T24 cells, which can be restored by forced FDFT1 expression. Further investigation into the downstream cholesterol pathway revealed that FDFT1 suppression redirects its substrate toward the non-sterol branch of the pathway, as evidenced by the upregulation of non-sterol branch-associated genes and a reduced total cholesterol level in the sterol branch. Since the non-sterol pathway leads to the prenylation of isoprenoids and activation of Ras and Rho family proteins involved in cancer progression and chemoresistance, our findings suggest that redirection of the cholesterol biosynthesis pathway is a key mechanism underlying FDFT1-mediated cisplatin resistance in bladder cancer. The miR-146b-5p/FDFT1 axis represents a promising target for overcoming chemoresistance in bladder cancer.

Evaluation of Tumorigenic Properties of MDA-MB-231 Cancer Stem Cells Cocultured with Telocytes and Telocyte-Derived Mitochondria Following miR-146a Inhibition

Telocytes have some cytoplasmic extensions called telopodes, which are thought to play a role in mitochondrial transfer in intercellular communication. Besides, it is hypothesized that telocytes establish cell membrane-mediated connections with breast cancer cells in coculture and may contribute to the survival of neoplastic cell clusters together with other stromal cells. The aim of this study is to investigate the contribution of telocytes and telocyte-derived mitochondria, which have also been identified in breast tumors, to the tumor development of breast cancer stem cells (CSCs) via miR-146a-5p. The isolation/characterization of telocytes from bone marrow mononuclear cells and the isolation of mitochondria from these cells were performed, respectively. In the next step, CSCs were isolated from the MDA-MB-231 cell line and were characterized. Then, miR-146a-5p expressions of CSCs were inhibited by anti-miR-146a-5p. The epithelial-mesenchymal transition (EMT) was determined by evaluating changes in vimentin protein levels and was evaluated by analyzing BRCA1, P53, SOX2, E-cadherin, and N-cadherin gene expression changes. Our results showed that miR-146a promoted stemness and oncogenic properties in CSCs. EMT (N-cadherin, vimentin, E-cadherin) and tumorigenic markers (BRCA1, P53, SOX2) of CSCs decreased after miR-146a inhibition. Bone marrow-derived telocytes and mitochondria derived from telocytes favored the reduction of CSC aggressiveness following this inhibition.

Deregulated miR-146a-3p alleviates disease progression in atherosclerosis through inactivating NF-κB: An experimental study

BACKGROUND

Atherosclerosis (AS), as a complex chronic inflammatory disease, is 1 of the main causes of cardiovascular and cerebrovascular diseases. This study aimed to confirm the direct interaction between miR-146a-3p and NF-κB, and explore the role of miR-146a-3p/NF-κB in the regulation of inflammation in AS.

METHODS

Bioinformatic prediction and dual-luciferase reporter assay were used to confirm the interaction between miR-146a-3p and NF-κB. Lipopolysaccharides stimulation was performed to establish AS inflammatory cell model, and the levels of pro-inflammatory cytokines were estimated using an enzyme-linked immunosorbent assay. miR-146a-3p and NF-κB expression were evaluated using reverse transcription quantitative PCR, and their clinical value was examined using a receiver operating characteristic curve.

RESULTS

Inflammatory cell model showed increased IL-1β, IL-6, and TNF-α. NF-κB was a target gene of miR-146a-3p, and mediated the inhibitory effects of miR-146a-3p on inflammatory responses in the cell model. In patients with AS, miR-146a-3p/NF-κB was associated with patients' clinical data and inflammatory cytokine levels, and aberrant miR-146a-3p and NF-κB showed diagnostic accuracy to distinguish AS patients from healthy populations.

CONCLUSION

miR-146a-3p might inhibit inflammation by targeting NF-κB in AS progression, and miR-146a-3p/ NF-κB might provide novel biomarkers and therapeutic targets for the prevention of AS and related vascular events.

Milk miRNA expression in buffaloes as a potential biomarker for mastitis

BACKGROUND

Buffaloes have the highest potential for production due to a promising gene pool that is being enhanced and upgraded. Mastitis is a significant health impediment that greatly diminishes milk yield and quality, affecting rural farmers' livelihoods. The traditional gold standard used for diagnosing mastitis or subclinical mastitis is CMT, but it has the drawback of false positive or negative results. Subclinical mastitis, if not treated promptly, can lead to mammary tumors. To address the gap in early diagnosis of subclinical mastitis in CMT-negative milk of buffaloes, we performed a retrospective analysis and evaluated the milk miRNA expression profiles as potential biomarkers.

RESULTS

Thirty buffalo milk samples based on clinical signs and CMT were divided into normal, subclinical, and clinical mastitis. SCC evaluation showed significant differences between the groups. The data analysis demonstrated that the elevation of miR-146a and miR-383 differed substantially between normal, subclinical, and clinical mastitis milk of buffaloes with 100% sensitivity and specificity. The relationship of SCC with miR-146a and miR-383 in normal/healthy and subclinical mastitis was positively correlated.

CONCLUSION

The overexpression of miR-146a and miR-383 is associated with inflammation. It can be a valuable prognostic and most sensitive biomarker for early mastitis detection in buffaloes with SCC below 2 lakhs and CMT-ve, enhancing the accuracy of subclinical mastitis diagnosis.

Role of microRNA-146a in cancer development by regulating apoptosis

Despite great advances in diagnostic and treatment options for cancer, like chemotherapy surgery, and radiation therapy it continues to remain a major global health concern. Further research is necessary to find new biomarkers and possible treatment methods for cancer. MicroRNAs (miRNAs), tiny non-coding RNAs found naturally in the body, can influence the activity of several target genes. These genes are often disturbed in diseases like cancer, which perturbs functions like differentiation, cell division, cell cycle, apoptosis and proliferation. MiR-146a is a commonly and widely used miRNA that is often overexpressed in malignant tumors. The expression of miR-146a has been correlated with many pathological and physiological changes in cancer cells, such as the regulation of various cell death paths. It's been established that the control of cell death pathways has a huge influence on cancer progression. To improve our understanding of the interrelationship between miRNAs and cancer cell apoptosis, it's necessary to explore the impact of miRNAs through the alteration in their expression levels. Research has demonstrated that the appearance and spread of cancer can be mitigated by moderating the expression of certain miRNA - a commencement of treatment that presents a hopeful approach in managing cancer. Consequently, it is essential to explore the implications of miR-146a with respect to inducing different forms of tumor cell death, and evaluate its potential to serve as a target for improved chemotherapy outcomes. Through this review, we provide an outline of miR-146a's biogenesis and function, as well as its significant involvement in apoptosis. As well, we investigate the effects of exosomal miR-146a on the promotion of apoptosis in cancer cells and look into how it could possibly help combat chemotherapeutic resistance.

A perspective on the metastasis suppressor field

Metastasis is the leading cause of cancer patient mortality. Metastasis suppressors are genes that, upon reexpression in metastatic tumor cells to levels observed in their nonmetastatic counterparts, significantly reduce metastasis without affecting the growth of the primary tumor. Analysis of > 30 metastasis suppressors revealed complex mechanisms of action that include multiple signaling pathways, transcriptional patterns, posttranscriptional regulatory mechanisms, and potential contributions of genomic stability. Clinical testing of strategies to re-establish a validated metastasis suppressor pathway in tumors is best directed to the adjuvant setting, with the goal of inhibiting the outgrowth of occult micrometastases.

MiRNA-146a-A Key Player in Immunity and Diseases

miRNA-146a, a single-stranded, non-coding RNA molecule, has emerged as a valuable diagnostic and prognostic biomarker for numerous pathological conditions. Its primary function lies in regulating inflammatory processes, haemopoiesis, allergic responses, and other key aspects of the innate immune system. Several studies have indicated that polymorphisms in miRNA-146a can influence the pathogenesis of various human diseases, including autoimmune disorders and cancer. One of the key mechanisms by which miRNA-146a exerts its effects is by controlling the expression of certain proteins involved in critical pathways. It can modulate the activity of interleukin-1 receptor-associated kinase, IRAK1, IRAK2 adaptor proteins, and tumour necrosis factor (TNF) targeting protein receptor 6, which is a regulator of the TNF signalling pathway. In addition, miRNA-146a affects gene expression through multiple signalling pathways, such as TNF, NF-κB and MEK-1/2, and JNK-1/2. Studies have been carried out to determine the effect of miRNA-146a on cancer pathogenesis, revealing its involvement in the synthesis of stem cells, which contributes to tumourigenesis. In this review, we focus on recent discoveries that highlight the significant role played by miRNA-146a in regulating various defence mechanisms and oncogenesis. The aim of this review article is to systematically examine miRNA-146a's impact on the control of signalling pathways involved in oncopathology, immune system development, and the corresponding response to therapy.

miR-146a-5p Promotes Angiogenesis and Confers Trastuzumab Resistance in HER2+ Breast Cancer

Trastuzumab treatment has significantly improved the prognosis of HER2-positive breast cancer patients. Despite this, resistance to therapy still remains the main clinical challenge. In order to evaluate the implication of microRNAs in the trastuzumab response, we performed a microRNA array in parental and acquired trastuzumab-resistant HER2-positive breast cancer cell lines. Our results identified miR-146a-5p as the main dysregulated microRNA. Interestingly, high miR-146a-5p expression in primary tumor tissue significantly correlated with shorter disease-free survival in HER2-positive breast cancer patients. The gain- and loss-of-function of miR-146a-5p modulated the response to trastuzumab. Furthermore, the overexpression of miR-146a-5p increased migration and angiogenesis, and promoted cell cycle progression by reducing CDKN1A expression. Exosomes from trastuzumab-resistant cells showed a high level of miR-146a-5p expression compared with the parental cells. In addition, the co-culture with resistant cells’ exosomes was able to decrease in sensitivity and increase the migration capacities in trastuzumab-sensitive cells, as well as angiogenesis in HUVEC-2 cells. Collectively, these data support the role of miR-146a-5p in resistance to trastuzumab, and demonstrate that it can be transferred by exosomes conferring resistance properties to other cells.

Interfering with the Ubiquitin-Mediated Regulation of Akt as a Strategy for Cancer Treatment

The serine/threonine kinase Akt modulates the functions of numerous substrates, many of them being involved in cell proliferation and growth, metabolism, angiogenesis, resistance to hypoxia and migration. Akt is frequently deregulated in many types of human cancers, its overexpression or abnormal activation being associated with the increased proliferation and survival of cancer cells. A promising avenue for turning off the functionality of Akt is to either interfere with the K63-linked ubiquitination that is necessary for Akt membrane recruitment and activation or increase the K48-linked polyubiquitination that aims to target Akt to the proteasome for its degradation. Recent evidence indicates that targeting the ubiquitin proteasome system is effective for certain cancer treatments. In this review, the functions and roles of Akt in human cancer will be discussed, with a main focus on molecules and compounds that target various elements of the ubiquitination processes that regulate the activation and inactivation of Akt. Moreover, their possible and attractive implications for cancer therapy will be discussed.

Identification of Potential Biomarkers in the Peripheral Blood Mononuclear Cells of Relapsing-Remitting Multiple Sclerosis Patients

Multiple sclerosis (MS) is described as an immune disorder with inflammation and neurodegeneration. Relapsing-remitting MS (RRMS) is one of the most common types of MS. The diagnostic manner for this disorder typically includes the usage of magnetic resonance imaging (MRI); however, this is not always a very precise diagnostic method. Identification of molecular biomarkers in RRMS body fluids samples compared to healthy subjects can be useful to indicate the normal and pathogenic biological processes or pharmacological responses to drug interaction. In this regard, this study evaluated different miRNAs in isolated peripheral blood mononuclear cells (PBMCs) of RRMS compared to controls and their correlations with altered T regulatory type 1 (Tr1) cells, osteopontin (OPN), and interleukin 10 (IL-10) levels. The frequency of Tr1 cells was measured using flow cytometry. Also, the expressions of different miRNAs were evaluated via quantitative real-time polymerase chain reaction (RT-qPCR) and plasma levels of IL-10 and OPN were tested by enzyme-linked immunosorbent assay (ELISA). The obtained results showed the Tr1 cells' frequency, Let7c-5p, and miR-299-5p levels decreased in RRMS patients to about 59%, 0.69%, and 20% of HCs, respectively, (P < 0.05). The miR-106a-5p levels increased about 7.5-fold in RRMS patients in comparison to HCs (P < 0.05). Moreover, the results showed that there was an increased negative association between Tr1 frequency and plasma-OPN levels in RRMS patients in comparison to HCs and also, we found a moderate positive correlation between plasma-IL-10 and miR-299-5p expression of RRMS patients. Overall, it may be possible to use these biomarkers to improve the diagnostic process. These biomarkers may also be considered for clinical and therapeutic studies in the future.

Association between extract of Euphorbia szovitsii and expression level of microRNAs in MDA-MB-231 cell line

BACKGROUND

The miRNAs have been shown to be involved in breast cancer. The aim of the present research was to evaluate the impacts of extract from Euphorbia szovitsii Fisch & C.A. Mey on the expression level of microRNAs in triple-negative breast cancer (MDA-MB-231) cell line.

METHODS AND RESULT

The alterations in the expression level of miRNAs in MDA-MB-231 cell line exposed to the extract of E. szovitsii were determined exploiting qRT-PCR technique. The expression of MDA-MB-231 cell microRNAs including miR-15, miR-16, miR-21, miR-29, miR-34a, miR-146b, miR-151, miR-155, miR-181b, miR-221, miR-222, and Let-7 was evaluated at 24 and 48 h after treatment with the E. szovitsii extract. The treatment of MDA-MB-231 cells with E. szovitsii caused a significant elevation in the expression of miR-155, miR-146b (P < 0.05), miR-16, miR-21, miR-151 (P < 0.01), and miR-34a (P < 0.001) after 24 h, and also miR-155, Let-7 (P < 0.05), miR-15, miR-29, miR-151 (P < 0. 01), miR-146b and miR-34a (P<0.001) after 48 h.

CONCLUSIONS

The qRT-PCR findings at 24 and 48 h after treatment revealed that the MDA-MB-231 cell line in the presence of E. szovitsii extract showed an alteration in the expression profile of miRNAs implicated in the induction of cell proliferation, apoptosis and migration. These results may be helpful in determining the anticancer activity of E. szovitsii in MDA-MB-231 cell line.

Study of microRNA expression profiling as biomarkers for colorectal cancer patients in Lebanon

The high incidence and mortality rates of colorectal cancer (CRC) reveal its hazardous effect globally. Thus, it is important to diagnose CRC at an early stage to decrease its burden and improve survival rates. Previous studies have investigated the role of short non-coding microRNAs (miRNAs or miRs) in numerous types of cancer, including CRC. Previous studies have been performed to investigate the role of miRNAs as biomarkers in diagnosis, prognosis and prediction of CRC development. The aim of the present retrospective study was to identify the expression levels of miR-31, miR-145, miR-146b and miR-186 to highlight their role in CRC diagnosis and progression at different stages of the disease (precancerous polyp, adenoma and adenocarcinoma) in a Lebanese population. The expression levels of miRNAs was revealed using TaqMan reverse transcription-quantitative PCR on formalin-fixed paraffin-embedded tissues from Lebanese patients at different stages; their diagnostic value was determined using a receiver operating characteristics curve. Compared with healthy controls, miR-31 was upregulated (P<0.0001) at all stages. By contrast, miR-145, miR-186, and miR-146b were significantly downregulated at all stages (P<0.0001, P=0.0009 and P=0.0241, respectively). Of the four miRNAs studied, miR-31 and miR-145 were identified as potentially useful diagnostic factors, with an area under the curve of 0.7771 and 0.8269 and diagnostic accuracy of 71.3 and 78.5%, respectively. These data suggested that miR-31 and miR-145, upon further clinical validation, may be used as potential diagnostic biomarkers for the early detection of CRC at the polyp stage.

miR-146a-5p and miR-193a-5p Synergistically Inhibited the Proliferation of Human Colorectal Cancer Cells (HT-29 cell line) through ERK Signaling Pathway

Purpose: The expression of miR-146a-5p and miR-193a-5p in colorectal cancer (CRC) is associated with cancer development, metastasis, and reduced survival rate of the tumor-suffered subjects. This examination aimed to assess the impact of these microRNAs (miRNAs) in CRC and their mechanisms in the proliferation and migration of cancer cells.

Methods: miR-146a-5p and -193a-5p were transfected into the HT-29 cell line and assessed their impact on metastasis-related genes. The synergistic effects of these miRNAs on migration were evaluated by wound healing approach. To assess the influence of these miRNAs on the proliferation of and apoptosis of cells, the MTT test, annexin V staining test, and DAPI staining test were done. Then, the protein expression of extracellular-signal-regulated kinase (ERK) and phosphorylated ERK (p-ERK) were investigated.

Results: miR-146a-5p and-193a-5p could inhibit the CRC cells proliferation, and could synergistically induce apoptosis in CRC cells, and also repressed cell migration, and could reduce p-ERK expression.

Conclusion: miR-146a-5p and-193a-5p have an important role in cell viability and proliferation via ERK signaling pathway. Thus, the simultaneous use of these miRNAs may be suggested as a probable therapeutic strategy in this cancer therapy.

In silico model for miRNA-mediated regulatory network in cancer

Deregulation of gene expression is associated with the pathogenesis of numerous human diseases including cancer. Current data analyses on gene expression are mostly focused on differential gene/transcript expression in big data-driven studies. However, a poor connection to the proteome changes is a widespread problem in current data analyses. This is partly due to the complexity of gene regulatory pathways at the post-transcriptional level. In this study, we overcome these limitations and introduce a graph-based learning model, PTNet, which simulates the microRNAs (miRNAs) that regulate gene expression post-transcriptionally in silico. Our model does not require large-scale proteomics studies to measure the protein expression and can successfully predict the protein levels by considering the miRNA-mRNA interaction network, the mRNA expression, and the miRNA expression. Large-scale experiments on simulations and real cancer high-throughput datasets using PTNet validated that (i) the miRNA-mediated interaction network affects the abundance of corresponding proteins and (ii) the predicted protein expression has a higher correlation with the proteomics data (ground-truth) than the mRNA expression data. The classification performance also shows that the predicted protein expression has an improved prediction power on cancer outcomes compared to the prediction done by the mRNA expression data only or considering both mRNA and miRNA. Availability: PTNet toolbox is available at http://github.com/CompbioLabUCF/PTNet.

Effects of Silver Nanoparticles and Silver Nitrate on mRNA and microRNA Expression in Human Hepatocellular Carcinoma Cells (HepG2)

In order to understand toxicity of nano silver, human hepatocellular carcinoma (HepG2) cells were treated either with silver nitrate (AgNO₃) or with nano silver capped with glutathione (Ag-S) at various concentration. Differentially expressed genelists for mRNA and microRNA were obtained through Illumina RNA sequencing and DEseq data analyses. Both treatments showed non-linear dose response relationships for mRNA and microRNA. Gene expression analysis showed signaling pathways common to both nano Ag-S and AgNO₃, such as cell cycle regulation, DNA damage response and cancer related pathways. But, nano Ag-S caused signaling pathway changes that were not altered by AgNO₃ such as NRF2-mediated oxidative stress response inflammation, cell membrane signaling, and cell proliferation. Nano Ag-S also affected p53 signaling, survival, apoptosis, tissue repair, lipid synthesis, angiogenesis, liver fibrosis and tumor development. Several of the pathways affected by nano Ag-S are hypothesized as major contributors to nanotoxicity. MicroRNA target filter analysis revealed additional affected pathways that were not reflected in the mRNA expression response alone, including DNA damage signaling, genomic stability, ROS, cell cycle, ubiquitination, DNA methylation, cell proliferation and fibrosis for AgNO₃; and cell cycle regulation, P53 signaling, cell proliferation, survival, apoptosis, tissue repair and so on for nano Ag-S. These pathways may be mediated by microRNA repression of protein translation.Our study clearly showed that the addition of microRNA profiling increased the numbers of signaling pathways discovered that affected by the treatments on HepG2 cells and gave US a better picture of the effects of these reagents in the cells.

Modulation of MicroRNAs by Euphorbia Microsciadia Boiss in MDA-MB-231 Cell Line: New Possibilities in Breast Cancer Therapy

BACKGROUND

A large number of Euphorbia species have been evaluated for anticancer effects; however, their anticancer mechanisms have not been established up to now.

OBJECTIVE

The present study aimed to evaluate the effects of Euphorbia microsciadia (E. microsciadia) Boiss on the modulation of micro (mi) RNAs in MDA-MB-231 cell line.

METHODS

As the first step, the inhibitory concentration of hydroalcoholic extract of E. microsciadia on MDA-MB-231 cells was examined using the MTT assay, bypassing 24 and 48h from seeding. The real-time quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) was also utilized to determine Let-7, miR-15, miR-16, miR-29, miR-151, miR-155, miR-21, miR-146b, miR-181b, miR-221, miR-222, miR-21, and miR-146b expressions in MDA-MB-231 cells, by passing 24 and 48h from treating with the extract of E. microsciadia.

RESULTS

The results reveal the cytotoxic effects of E. microsciadia on MDA-MB-231 cell line in a dose-dependent manner. The half maximal Inhibitory Concentrations (IC50) were also equal to 275 and 240μg/ml for E. microsciadia, by passing 24 and 48h from the treatment, respectively. Furthermore, it was confirmed that, E. microsciadia had augmented the expression levels of Let-7, miR-15, miR-16, miR-29, and miR-34a, which lead to an increase in apoptosis.

CONCLUSION

E. microsciadia could modulate some miRNAs involved in cell cycle arrest and apoptosis in MDA-MB-231 cell line. Accordingly, targeting miRNAs by E. microsciadia can open some newer avenues for breast cancer therapy.

Role of L1CAM in retinoblastoma tumorigenesis: identification of novel therapeutic targets

The study presented focuses on the role of the neuronal cell adhesion molecule L1 cell adhesion molecule (L1CAM) in retinoblastoma (RB), the most common malignant intraocular childhood tumor. L1CAM is differentially expressed in a variety of human cancers and has been suggested as a promising therapeutic target. We likewise observed differential expression patterns for L1CAM in RB cell lines and patient samples. The two proteases involved in ectodomain shedding of L1CAM (L1CAM sheddases: ADAM10 and ADAM17) were likewise differentially expressed in the RB cell lines investigated, and an involvement in L1CAM processing in RB cells could be verified. We also identified ezrin, galectin-3, and fibroblast growth factor basic as L1CAM signaling target genes in RB cells. Lentiviral L1CAM knockdown induced apoptosis and reduced cell viability, proliferation, growth, and colony formation capacity of RB cells, whereas L1CAM-overexpressing RB cells displayed the opposite effects. Chicken chorioallantoic membrane assays revealed that L1CAM depletion decreases the tumorigenic and migration potential of RB cells in vivo. Moreover, L1CAM depletion decreased viability and tumor growth of etoposide-resistant RB cell lines upon etoposide treatment in vitro and in vivo. Thus, L1CAM and its processing sheddases are potential novel targets for future therapeutic RB approaches.

Colorectal cancer prompted adipose tissue browning and cancer cachexia through transferring exosomal miR-146b-5p

Cancer cachexia is a complex syndrome that is associated with thermogenic gene regulation. Currently, although some studies have reported the link between exosomes and cancer cachexia in a few types of cancer, the underlying mechanisms remain poorly understood. In this study, we tried to identify whether exosomes derived from colorectal cancer could affect lipolysis in vitro and in vivo. Here, we collected the tissue samples from 48 patients with colorectal cancer (47.91% females and mean age 55 ± 8.20) and 48 healthy people at the First Affiliated Hospital of Nanjing Medical University to detect the miR-146-5p expression. Here, we found that cancer cells released exosomes induced white adipose tissues (WATs) browning and accelerated lipolysis. We also demonstrated that miR-146b-5p was enriched in cancer-related exosomes. Overexpression miR-146b-5p resulted in increased WAT browning, decreased oxygen consumption, and fat mass loss (14.57%). The further study identified that miR-146b-5p could directly repress the downstream gene homeodomain-containing gene C10 (HOXC10), thereby regulating lipolysis. Therefore, our results indicated that cancer cells derived from exosomal miR-146b-5p played an essential role in WAT browning. Inhibition of cancer-related exosomes might be necessary for improving the cachexia condition.

Regulation of bone metastasis and metastasis suppressors by non-coding RNAs in breast cancer

Breast cancer (BC) is a critical health care issue that substantially affects women worldwide. Though surgery and chemotherapy can effectively control tumor growth, metastasis remains a primary concern. Metastatic BC cells predominantly colonize in bone, owing to their rigid osseous nutrient-rich nature. There are recently increasing studies investigating the context-dependent roles of non-coding RNAs (ncRNAs) in metastasis regulation. ncRNAs, including microRNAs, long non-coding RNAs, circular RNAs, and small interference RNAs, control the BC metastasis via altered mechanisms. Additionally, these ncRNAs have been reported in regulating a unique class of genes known as Metastatic suppressors. Metastasis suppressors like BRMS1, NM23, LIFR, and KAI1, etc., have been extensively studied for their role in inducing apoptosis, inhibiting metastasis, and maintaining homeostasis. In this review, we have emphasized the direct regulation of ncRNAs for effectively controlling the distant spread of BC. Furthermore, we have highlighted the ncRNA-mediated modulation of the metastatic suppressors, thereby delineating their indirect influence over metastasis.

Angiogenesis-related non-coding RNAs and gastrointestinal cancer

Gastrointestinal (GI) cancers are among the main reasons for cancer death globally. The deadliest types of GI cancer include colon, stomach, and liver cancers. Multiple lines of evidence have shown that angiogenesis has a key role in the growth and metastasis of all GI tumors. Abnormal angiogenesis also has a critical role in many non-malignant diseases. Therefore, angiogenesis is considered to be an important target for improved cancer treatment. Despite much research, the mechanisms governing angiogenesis are not completely understood. Recently, it has been shown that angiogenesis-related non-coding RNAs (ncRNAs) could affect the development of angiogenesis in cancer cells and tumors. The broad family of ncRNAs, which include long non-coding RNAs, microRNAs, and circular RNAs, are related to the development, promotion, and metastasis of GI cancers, especially in angiogenesis. This review discusses the role of ncRNAs in mediating angiogenesis in various types of GI cancers and looks forward to the introduction of mimetics and antagonists as possible therapeutic agents.

Long Noncoding RNA HCG11 Acts as a Tumor Suppressor in Gastric Cancer by Regulating miR-942-5p/BRMS1 Axis

The functions of long noncoding RNAs (lncRNAs) have been widely investigated in human cancers, including gastric cancer (GC). The purpose of this study was to elucidate the role of lncRNA HCG11 in GC. In this study, mRNA and protein expressions were detected by quantitative real-time polymerase chain reaction assays (RT-qPCR) and Western blot analysis. The proliferation ability of GC cells was examined by (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl Tetrazolium Bromide) MTT assays. The invasion and migration abilities of GC cells were evaluated by Transwell assays. The binding sites between miR-942-5p and HCG11/BRMS1 were confirmed by dual-luciferase reporter assays. Results showed that LncRNA HCG11 was downregulated in GC cells. Functionally, overexpression of HCG11 inhibited GC cell proliferation, migration, and invasion. In addition, lncRNA HCG11 was found to act as a molecular sponge of miR-942-5p. Furthermore, miR-942-5p promoted GC progression by suppressing lncRNA HCG11 expression. Besides that, BRMS1 was confirmed as a direct target of miR-942-5p. More importantly, breast cancer metastasis suppressor 1 (BRMS1) inhibited GC progression by upregulating lncRNA HCG11 and downregulating miR-942-5p. In conclusion, LncRNA HCG11 inhibited cell proliferation, migration, and invasion in GC by sponging miR-942-5p and upregulating BRMS1.

Propolis Extract Regulate microRNA Expression in Glioblastoma and Brain Cancer Stem Cells

BACKGROUND

Grade IV gliomas are classified as glioblastoma (GBM), which is the most malignant brain cancer type. Various genetic and epigenetic mechanisms play a role in the initiation and progression of GBM. MicroRNAs (miRNAs) are small, non-coding RNA molecules that are the main epigenetic regulatory RNA class. They play variable roles in both physiological and pathological conditions, including GBM pathogenesis, by regulating expression levels of the target genes. Brain cancer stem cells (BCSCs) are subpopulations of brain cancer mass that are responsible for poor prognosis, including therapy resistance and relapse. Epigenetic regulation mediated by miRNAs is also a critical component of BCSC self-renewal and differentiation properties. Propolis is a resinous substance that is collected by honey bees from various plant sources. The flavonoids content of propolis varies, depending on the region collected andthe extraction method. Although the effects of propolis that have been collected from different sources on the miRNA expression levels in the glioblastoma cells have been shown, the effects on the BCSCs are not known yet.

OBJECTIVE

The aim of this study is to evaluate the effects of Aydın, a city in western Turkey, propolis, on miRNA expression levels of BCSCs and GBM cells.

METHODS

Aydin propolis was dissolved in 60% ethanol, and after evaporation, distilled water was added to prepare the propolis stock solution. The flavonoids content of the Aydin propolis was determined by MS Q-TOF analysis. Commercially obtained U87MG, GBM cell line, and BCSCs were used as in vitro brain cancer models. The cytotoxic and apoptotic effects of Aydın propolis were determined via WST-1 assay and Annexin V test, respectively. The miRNA expression profile was investigated via the real-time qRT-PCR method, and fold changes were calculated by using the 2-^∆∆Ct method compared to untreated control cells. The miRNA-mRNA-pathway interactions, including significantly altered miRNAs, were determined using different bioinformatics tools and databases.

RESULTS

Quercetin 3-methyl ether was determined as the major component of the Aydin propolis. Aydin propolis did not show significant cytotoxic and apoptotic effects on both GBM and BCSCs up to 2mg/ml concentration. Aydin propolis treatment decreased the expression of nine and five miRNAs in the U87MG 2.13 to 5.65 folds and BCSCs 2.02 to 12.29 folds, respectively. Moreover, 10 miRNAs 2.22 to 10.56 folds were upregulated in propolis treated GBM cells compared to the control group, significantly (p<0.05). In the study, the potential roles of two new miRNAs, whose regulations in glioma were not previously defined, were identified. One of these miR-30d-5p, a novel potential oncomiR in GBM was 2.46 folds downregulated in Aydin propolis treated GBM cells. The other one is miR-335-5p which is a potential tumor suppressor miR in GBM, was 5.66 folds upregulated in Aydin propolis treated GBM cells. FOXO pathway and its upstream and downstream regulators and critically neuronal developmental regulators NOTCH and WNT pathways were determined as the most deregulated pathways in Aydin propolis treated cells.

CONCLUSION

The determination of the anti-cancer effect of Aydın propolis on the miRNA expression of GBM, especially on cancer stem cells, may contribute to the elucidation of brain cancer genetics by supporting further analyses.

lncRNA‑CASC15 promotes osteosarcoma proliferation and metastasis by regulating epithelial‑mesenchymal transition via the Wnt/β‑catenin signaling pathway

Osteosarcoma (OS) is a rare type of tumor and mostly occurs in children and adolescents. Approximately 10–25% of patients with OS have lung metastases, and lung damage caused by lung metastasis is the main cause of mortality. Therefore, studying the growth and metastasis of OS is key in reducing OS mortality and improving prognosis. The expression of long non-coding RNA (lncRNA) cancer susceptibility 15 (CASC15) in OS patients or OS cell lines were quantified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The expression of vimentin, E-cadherin, N-cadherin, and cyclin D were detected by RT-qPCR and western blotting. Mice were injected with OS cell lines via the tail vein to observe tumor formation in the lung. CCK-8 and EdU assays were utilized to evaluate cell proliferation. Both Ttranswell assay and cell scratch test detected cell migration. The results revealed that lncRNA-CASC15 was highly expressed in clinical samples and OS cells. In vitro verification experiments revealed that CASC15 promoted the growth of OS cells. Rescue experiments demonstrated that CASC15 affected the cell cycle by activating the Wnt/β-catenin pathway, thereby promoting cell proliferation. Furthermore, the transfection dose test indicated that lentiviruses expressing various doses of CASC15-overexpression (oe-CASC15) altered the proliferation and migration status of OS cells. CASC15 promoted OS cell metastasis both in vivo and in vitro. The overexpression of CASC15 revealed that the occurrence of metastasis was also related to the Wnt/β-catenin pathway. The western blotting results revealed that CASC15 could lead to β-catenin entering the nucleus via the Wnt pathway to promote the epithelial-mesenchymal transition (EMT) of OS cells. To sum up, CASC15 promoted the proliferation of OS cells in vitro and the growth of OS xenograft tumors in vivo. Moreover, CASC15 promoted the entry of β-catenin into the nucleus, thus activating the Wnt pathway and subsequently promoting the EMT of OS cells.

Molecular mediators of breast cancer metastasis

Breast cancer has the highest incidence rate of malignancy in women worldwide. A major clinical challenge faced by patients with breast cancer treated by conventional therapies is frequent relapse. This relapse has been attributed to the cancer stem cell (CSC) population that resides within the tumor and possess stemness properties. Breast CSCs are generated when breast cancer cells undergo epithelial-mesenchymal transition resulting in aggressive, highly metastatic, and invasive phenotypes that exhibit resistance towards chemotherapeutics. Metastasis, a phenomenon that aids in the migration of breast CSCs, occurs through any of three different routes: hematogenous, lymphatic, and transcoelomic. Hematogenous dissemination of breast CSCs leads to metastasis towards distant unrelated organs like lungs, liver, bone, and brain causing secondary tumor generation. Activation of metastasis genes or silencing of metastasis suppressor genes often leads to the advancement of metastasis. This review focuses on various genes and molecular factors that have been implicated to regulate organ-specific breast cancer metastasis by defying the available therapeutic interventions.

Regulation of breast cancer metastasis signaling by miRNAs

Despite the decline in death rate from breast cancer and recent advances in targeted therapies and combinations for the treatment of metastatic disease, metastatic breast cancer remains the second leading cause of cancer-associated death in U.S. women. The invasion-metastasis cascade involves a number of steps and multitudes of proteins and signaling molecules. The pathways include invasion, intravasation, circulation, extravasation, infiltration into a distant site to form a metastatic niche, and micrometastasis formation in a new environment. Each of these processes is regulated by changes in gene expression. Noncoding RNAs including microRNAs (miRNAs) are involved in breast cancer tumorigenesis, progression, and metastasis by post-transcriptional regulation of target gene expression. miRNAs can stimulate oncogenesis (oncomiRs), inhibit tumor growth (tumor suppressors or miRsupps), and regulate gene targets in metastasis (metastamiRs). The goal of this review is to summarize some of the key miRNAs that regulate genes and pathways involved in metastatic breast cancer with an emphasis on estrogen receptor α (ERα+) breast cancer. We reviewed the identity, regulation, human breast tumor expression, and reported prognostic significance of miRNAs that have been documented to directly target key genes in pathways, including epithelial-to-mesenchymal transition (EMT) contributing to the metastatic cascade. We critically evaluated the evidence for metastamiRs and their targets and miRNA regulation of metastasis suppressor genes in breast cancer progression and metastasis. It is clear that our understanding of miRNA regulation of targets in metastasis is incomplete.

MiR-146a Regulates Migration and Invasion by Targeting NRP2 in Circulating-Tumor Cell Mimicking Suspension Cells

Cancer metastasis is the primary cause of cancer-related death and metastatic cancer has circulating-tumor cells (CTCs), which circulate in the bloodstream before invading other organs. Thus, understanding the precise role of CTCs may provide new insights into the metastasis process and reduce cancer mortality. However, the molecular characteristics of CTCs are not well understood due to a lack of number of CTCs. Therefore, suspension cells were generated from MDA-MB-468 cells to mimic CTCs, and we investigate the microRNA (miRNA)-dependent molecular networks and their role in suspension cells. Here, we present an integrated analysis of mRNA and miRNA sequencing data for suspension cell lines, through comparison with adherent cells. Among the differentially regulated miRNA–mRNAs axes, we focus on the miR-146a-Neuropilin2 (NRP2) axis, which is known to influence tumor aggressiveness. We show that miR-146a directly regulates NRP2 expression and inhibits Semaphorin3C (SEMA3C) signaling. Functional studies reveal that miR-146a represses SEMA3C-induced invasion and proliferation by targeting NRP2. Finally, high-NRP2 is shown to be associated with poor outcomes in breast cancer patients. This study identifies the key role of the miR-146a–NRP2 signaling axis that is critical for the regulation of migration and invasion in CTC-mimicking cells.

MiR-146a functions as a potential tumor suppressor in retinoblastoma by negatively regulate neuro-oncological ventral antigen-1

MicroRNAs (miRNAs) are dysregulated in many tumors and have been found to play crucial roles in cancer biology. Retinoblastoma is a rare tumor that develops rapidly from a malignant tumor of immature cells in the retina known as photoreceptor progenitors. Our study aimed to explore the role of miR-146a in the pathology of retinoblastoma. Potential target gene of miR-146a was predicted by Targetscan. Reverse transcription quantitative polymerase chain reaction (RT-PCR) showed that miR-146a was downregulated and ventral nerve tumor antigen 1 (Neuro - oncological ventral antigen 1, NOVA1) was upregulated in retinoblastoma. Luciferase assay confirmed that miR-146a directly target NOVA1. MiR-146a knockdown and overexpression experiments were performed and found that miR-146a could regulate the expression of NOVA1. The miR-146a knockdown and overexpression experiments were conducted to investigate the biological function of miR-146a. MiR-146a was found inhibited the viability, proliferation and invasion of retinoblastoma cell by MTT, EdU, and transwell assays. Flow cytometry was performed for the apoptosis analysis and miR-146a increased the apoptosis of retinoblastoma cell was found. Above phenomenon can be rescued by overexpression of NOVA1. In conclusion, these results suggest that miR-146a acts as a tumor suppressor and can act as a potential therapeutic target for retinoblastoma in the future.

MicroRNA-146a suppresses tumor malignancy via targeting vimentin in esophageal squamous cell carcinoma cells with lower fibronectin membrane assembly

Background

Esophageal squamous cell carcinoma (ESCC) is widely prevalent in Taiwan, and high metastatic spread of ESCC leads to poor survival rate. Fibronectin (FN) assembly on the cell membrane may induce ESCC mobility. MicroRNAs (MiRNAs) are abundant in and participate in tumorigenesis in many cancers. However, the role of MiRNA in FN assembly-related ESCC mobility remains unexplored.

Methods

We divided ESCC CE81T cells into high-FN assembly (CE81^FN+) and low-FN assembly (CE81^FN−) groups by flow cytometry. MiRNA microarray analysis identified miR-146a expression as the most down-regulated miRNA in comparison of CE81^FN+ and CE81^FN− cells.

Results

Cell proliferation and migration were decreased when CE81^FN+ cells overexpressed transgenic miR-146a compared to the parental cells, indicating an inverse correlation between low miR-146a expression and high proliferation as well as motility of FN assembly ESCC cells. Furthermore, vimentin is the target gene of miR-146a involved in ESCC tumorigenesis. MiR-146a suppressed cell proliferation, migration and invasion of CE81^FN+ cells through the inhibition of vimentin expression, as confirmed by real-time PCR, Western blotting and Transwell™ assay. Analysis of one hundred and thirty-six paired ESCC patient specimens revealed that low miR-146a and high vimentin levels were frequently detected in tumor, and that the former was associated with late tumor stages (III and IV). Notably, either low miR-146a expression or high vimentin level was significantly associated with poor overall survival rate among ESCC patients.

Conclusions

This is the first report to link FN assembly in the cell membrane with miR-146a, vimentin and ESCC tumorigenesis both in vitro and in ESCC patients.

Long Non-Coding RNA A2M-AS1 Promotes Breast Cancer Progression by Sponging microRNA-146b to Upregulate MUC19

Background

Long non-coding RNA (lncRNA) A2M-AS1 has been indicated to be augmented in breast cancer (BC), with its specific function undetermined. Therefore, this study is designed to investigate the mechanism of lncRNA A2M-AS1 in BC.

Methods

The expression of A2M-AS1, microRNA (miR)-146b, and MUC19 in BC tissues and cells was measured. Then, the interaction among A2M-AS1, miR-146b, and MUC19 was detected. After A2M-AS1, miR-146b, and MUC19 expression were altered in BC cells, cell proliferation, invasion, and apoptosis were detected, and the protein levels of Hippo-related proteins (YAP and p-YAP) were evaluated. Tumor growth assay was also performed to validate the effects of A2M-AS1 and miR-146b in vivo.

Results

A2M-AS1 and MUC19 were highly expressed in BC, while miR-146b was poorly expressed. A2M-AS1 acts as a molecular sponge for miR-146b, which targeted and negatively modulated MUC19. A2M-AS1 accelerated BC cell proliferation, invasion, and colony formation and suppressed apoptosis via the miR-146b/MUC19/Hippo axis, which was confirmed in vivo.

Conclusion

Taken above together, an oncogenic role for A2M-AS1 in BC was elicited by acting as a miR-146b sponge to promote MUC19 expression. The findings will present some cues for a further approach to BC.

Nuclear Factor Erythroid 2-Related Factor 2 in Regulating Cancer Metabolism

Significance: Nuclear factor erythroid 2 (NFE2)-related factor 2 (NFE2L2, or NRF2) is a transcription factor predominantly affecting the expression of antioxidant genes. NRF2 plays a significant role in the control of redox balance, which is crucial in cancer cells. NRF2 activation regulates numerous cancer hallmarks, including metabolism, cancer stem cell characteristics, tumor aggressiveness, invasion, and metastasis formation. We review the molecular characteristics of the NRF2 pathway and discuss its interactions with the cancer hallmarks previously listed. Recent Advances: The noncanonical activation of NRF2 was recently discovered, and members of this pathway are involved in carcinogenesis. Further, cancer-related changes (e.g., metabolic flexibility) that support cancer progression were found to be redox- and NRF2 dependent. Critical Issues: NRF2 undergoes Janus-faced behavior in cancers. The pro- or antineoplastic effects of NRF2 are context dependent and essentially based on the specific molecular characteristics of the cancer in question. Therefore, systematic investigation of NRF2 signaling is necessary to clarify its role in cancer etiology. The biggest challenge in the NRF2 field is to determine which cancers can be targeted for better clinical outcomes. Further, large-scale genomic and transcriptomic studies are missing to correlate the clinical outcome with the activity of the NRF2 system. Future Directions: To exploit NRF2 in a clinical setting in the future, the druggable members of the NRF2 pathway should be identified. In addition, it will be important to study how the modulation of the NRF2 system interferes with cytostatic drugs and their combinations.

Circulating miRNAs in HER2-Positive and Triple Negative Breast Cancers: Potential Biomarkers and Therapeutic Targets

Breast cancer is one of the most prevalent diseases among women worldwide and is highly associated with cancer-related mortality. Of the four major molecular subtypes, HER2-positive and triple-negative breast cancer (TNBC) comprise more than 30% of all breast cancers. While the HER2-positive subtype lacks estrogen and progesterone receptors and overexpresses HER2, the TNBC subtype lacks estrogen, progesterone and HER2 receptors. Although advances in molecular biology and genetics have substantially ameliorated breast cancer disease management, targeted therapies for the treatment of estrogen-receptor negative breast cancer patients are still restricted, particularly for TNBC. On the other hand, it has been demonstrated that microRNAs, miRNAs or small non-coding RNAs that regulate gene expression are involved in diverse biological processes, including carcinogenesis. Moreover, circulating miRNAs in serum/plasma are among the most promising diagnostic/therapeutic tools as they are stable and relatively easy to quantify. Various circulating miRNAs have been identified in several human cancers including specific breast cancer subtypes. This review aims to discuss the role of circulating miRNAs as potential diagnostic and prognostic biomarkers as well as therapeutic targets for estrogen-receptor negative breast cancers, HER2+ and triple negative.

Evaluation of microRNA Gene Polymorphisms in Liver Transplant Patients with Hepatocellular Carcinoma

Background: Genetic polymorphism in the miRNA sequence might alter miRNA expression and/or maturation, which is associated with the development and progression of hepatocellular carcinoma (HCC) in liver transplant patients. Objectives: Therefore, the prevalence of miRNA-146a G > C (rs2910164), miRNA-499A > G (rs3746444), miRNA-149C > T (rs2292832), and miRNA-196a-2 C > T (rs11614913) gene polymorphisms was evaluated in liver recipients with HCC with or without experiencing graft rejection. Methods: In a cross-sectional study, tissue samples were collected from 60 HCC patients who underwent liver transplant surgery at Namazi Hospital, Shiraz, Iran, in 2013 - 2015. A control group consisting of 120 individuals was randomly selected, as well. The genomic DNA was extracted from collected tissues and blood samples. The miRNA-146a (rs2910164), miRNA-499 (rs3746444), miRNA-149 (rs2292832), and miRNA-196a-2 (rs11614913) gene polymorphisms were evaluated in patients with HCC using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: The CC genotype and C allele of the miRNA-146a (rs2910164) polymorphism were significantly associated with the increased risk of transplant rejection in patients with HCC (P = 0.05 and P = 0.05, respectively). The CC genotype and C allele of the miRNA-146a (rs2910164) were also significantly more frequent in male liver transplant patients who experienced acute rejection than in non-rejected ones (P = 0.05 and P = 0.03, respectively). However, no significant association was found between the genotypes and alleles of miRNA-499 (rs3746444), miRNA-149 (rs2292832), and miRNA-196a-2 (rs11614913) polymorphisms and HCC outcomes in liver transplant recipients. Conclusions: The importance of the CC genotype and C allele of the miRNA-146a (rs2910164) polymorphism in increasing the risk of transplant rejection was confirmed, but it needs further studies in larger populations.

Recent Trends of microRNA Significance in Pediatric Population Glioblastoma and Current Knowledge of Micro RNA Function in Glioblastoma Multiforme

Central nervous system tumors are a significant problem for modern medicine because of their location. The explanation of the importance of microRNA (miRNA) in the development of cancerous changes plays an important role in this respect. The first papers describing the presence of miRNA were published in the 1990s. The role of miRNA has been pointed out in many medical conditions such as kidney disease, diabetes, neurodegenerative disorder, arthritis and cancer. There are several miRNAs responsible for invasiveness, apoptosis, resistance to treatment, angiogenesis, proliferation and immunology, and many others. The research conducted in recent years analyzing this group of tumors has shown the important role of miRNA in the course of gliomagenesis. These particles seem to participate in many stages of the development of cancer processes, such as proliferation, angiogenesis, regulation of apoptosis or cell resistance to cytostatics.

Genetic variations in MicroRNA genes and cancer risk: A field synopsis and meta-analysis

BACKGROUND

Cancer risk has been associated with certain gene variations in microRNA (miRNA), but conflicting evidence warrants re-assessing of significant results in meta-analyses. We summarized published meta-analyses that assess the associations between miRNA polymorphism and cancers to show the validity of the findings.

METHOD

We searched PubMed and investigated the results of meta-analyses published through November 2018. We re-assessed the results based on false-positive report probability (FPRP) to test the noteworthiness of the associations.

RESULTS

Sixty-eight miRNA polymorphisms in 45 meta-analyses associated with cancer were included. Four (7.4%) and sixteen (25.0%) single nucleotide polymorphisms (SNPs) were noteworthy (FPRP < 0.2) at a prior probability of 0.001 for interesting candidate genes and a statistical power to detect an odds ratio (OR) of 1.1 and 1.5, respectively. The four miRNA SNPs noteworthy at an OR of 1.1 were as follows: miR-146a/rs2910164 Cvs.G; miR-27a/rs895819 Cvs.T; miR-423/rs6505162 Cvs.A; and miR-605/rs2043556 Cvs.T. The 16 SNPs noteworthy at an OR of 1.5 include the four genotype comparisons at an OR of 1.1, and the additional 12 genotype comparisons were as follows: miR-196a2/rs11614913 Tvs.C; miR-27a/rs895819 GGvs.AA + AG; miR-196a2/rs11614913 C vs.T; miR-146a/rs2910164 Gvs.C; miR-196a2/rs11614913 Tvs.C; miR-146a/rs2910164 Cvs.G; miR-499/rs3746444 homozygous model; miR-146a/rs2910164 CCvs.GG + GC; miR-499/rs3746444 TCvs.TT; miR-499/rs3746444 GAvs.AA; miR-146a/rs2910164 CCvs.GG; and miR-499/rs3746444 Gvs.A. No association was noteworthy at a prior probability of 0.000001.

CONCLUSION

Out of 68 published associations of miRNA polymorphisms with cancer, sixteen have shown noteworthiness in our re-assessing meta-analysis. Our findings summarize the results of meta-analyses on the association of cancer with SNPs and underline the importance of interpreting results with caution.

Micro RNA Molecules as Modulators of Treatment Resistance, Immune Checkpoints Controllers and Sensitive Biomarkers in Glioblastoma Multiforme

Based on genome sequencing, it is estimated that over 90% of genes stored in human genetic material are transcribed, but only 3% of them contain the information needed for the production of body proteins. This group also includes micro RNAs representing about 1%–3% of the human genome. Recent studies confirmed the hypothesis that targeting molecules called Immune Checkpoint (IC) open new opportunities to take control over glioblastoma multiforme (GBM). Detection of markers that indicate the presence of the cancer occupies a very important place in modern oncology. This function can be performed by both the cancer cells themselves as well as their components and other substances detected in the patients’ bodies. Efforts have been made for many years to find a suitable marker useful in the diagnosis and monitoring of gliomas, including glioblastoma.

Ablation of miR-146b in mice causes hematopoietic malignancy

Excessive and constitutive activation of nuclear factor-κB (NF-κB) leads to abnormal cell proliferation and differentiation, leading to the development of malignant tumors, including lymphoma. MicroRNA 146a (miR-146a) and miR-146b, both of which carry an identical seed sequence, have been shown to contribute to inflammatory diseases and tumors by suppressing the expression of key molecules required for NF-κB activation. However, the functional and physiological differences between miR-146a and miR-146b in disease onset have not been fully elucidated. In this study, we generated miR-146b-knockout (KO) and miR-146a-KO mice by genome editing and found that both strains developed hematopoietic malignancies such as B-cell lymphoma and acute myeloid leukemia during aging. However, the B-cell lymphomas observed in miR-146a- and miR-146b-KO mice were histologically different in their morphology, and the malignancy rate is lower in miR-146b mice than miR-146a mice. Upon mitogenic stimulation, the expression of miR-146a and miR-146b was increased, but miR-146b expression was lower than that of miR-146a. Using a previously developed screening system for microRNA targets, we observed that miR-146a and miR-146b could target the same mRNAs, including TRAF6, and inhibit subsequent NF-κB activity. Consistent with these findings, both miR-146a- and miR-146b-KO B cells showed a high proliferative capacity. Taken together, sustained NF-κB activation in miR-146b KO mice could lead to the development of hematopoietic malignancy with aging.

Multiple roles of microRNA-146a in immune responses and hepatocellular carcinoma

MicroRNAs (miRNAs/miRs), consisting of ~22 nucleotides of single-stranded RNA, participate in post-transcriptional gene regulation by binding to the 3′-untranslated region (UTR) of mRNAs, repressing their translation and promoting their degradation. Studies have shown that certain miRNAs play a key role in the control of various cellular activities, such as inhibiting inflammation, modulating cell differentiation and suppressing cancer growth. The role of miR-146a in the immune response and in the pathogenesis of hepatocellular carcinoma (HCC) has also been investigated. Although some studies have shown that increased miR-146a levels are associated with HCC, others have revealed that miR-146a suppresses cancer cell proliferation, invasion and metastasis. Toll-like receptor 4 (TLR4) signaling has an important role in regulating innate and adaptive immune responses. In addition, TLR4 is functionally expressed in HCC cells and promotes HCC cell proliferation, which can be regulated by miR-146a. The present review focuses on the recent progress in analyzing the multiple roles of miR-146a in mediating the TLR4 pathway and adaptive immune response. Finally, the function of miR-146a in the pathogenesis of HCC is also discussed.

MicroRNA expression profile in Treg cells in the course of primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is an autoimmune bleeding disorder which characterizes with platelet production impairment and platelet destruction increment. CD4⁺CD25⁺Foxp3⁺ Treg cells (Tregs) are involved in the immune pathogenesis of ITP. MicroRNAs (miRNAs) are also involved in ITP and their loss of function is shown to facilitate immune disorders. Thus, the miRNA expression profile in Tregs from ITP was analyzed in this study. We assessed the genome-wide miRNA expression profile of three newly diagnosed adult patients with ITP and three healthy controls using microarray analysis of CD4⁺CD25⁺CD127^dim/− Tregs that were sorted using an immune magnetic bead kit. The miRNA microarray chip was based on miRBase 18.0 and Volcano Plot filtering software used to analyze the miRNA profile in Tregs. Distinct miRNA expression was further validated by fluorescence-based real-time quantitative PCR (qPCR). We found that 502 human miRNAs were differentially expressed (244 upregulated and 258 downregulated) in patients with ITP compared with healthy donors. We identified 37 miRNAs expressed significantly, including 26 upregulated and 11 downregulated. Among the deregulated miRNAs, three downregulated miRNAs including miR-155–5p, miR-146b-5p, and miR-142–3p were selected for qPCR verification. We confirmed that miR-155–5p, miR-146b–5p, and miR-142–3p were significantly decreased in Tregs from patients with ITP compared with healthy controls. Compared with the healthy controls, miRNAs expressed differentially in the Tregs of patients with ITP. The levels of expression of miR-155–5p, miR-146b-5p, and miR-142–3p were significantly decreased. Therefore, the deregulation of miRNAs may affect the function of Tregs in the course of ITP.

The Inhibition on MDFIC and PI3K/AKT Pathway Caused by miR-146b-3p Triggers Suppression of Myoblast Proliferation and Differentiation and Promotion of Apoptosis

Accumulating studies report that microRNAs (miRNAs) are actively involved in skeletal myogenesis. Previously, our study revealed that miR-146b-3p was related to the growth of skeletal muscle. Here, we further report that miR-146b-3p is essential for the proliferation, differentiation, and apoptosis of chicken myoblast. Elevated expression of miR-146b-3p can dramatically suppress proliferation and differentiation, and facilitate apoptosis of chicken myoblast. Besides, we identified two target genes of miR-146b-3p, AKT1 and MDFIC, and found that miR-146b-3p can inhibit the PI3K/AKT pathway. Our study also showed that both AKT1 and MDFIC can promote the proliferation and differentiation while inhibit the apoptosis of myoblast in chicken. Overall, our results demonstrate that miR-146b-3p, directly suppressing PI3K/AKT pathway and MDFIC, acts in the proliferation, differentiation, and apoptosis of myoblast in chicken.

Protective potential of miR-146a-5p and its underlying molecular mechanism in diverse cancers: a comprehensive meta-analysis and bioinformatics analysis

Background/aims

Studies have shown that miR-146a-5p was differentially expressed in diverse cancers, but the associations between miR-146a-5p expression and prognosis across multiple types of cancer as well its potential targets and downstream pathways have not been comprehensively analyzed. In this study, we performed the first meta-analysis of the prognostic value of miR-146a-5p expression in diverse malignancies and explored prospective targets of miR-146a-5p and related signaling pathways.

Methods

A thorough search for articles related to miR-146a-5p was performed, and RNA-seq data from The Cancer Genome Atlas (TCGA) and microarray data from gene expression omnibus profiles were used to collect information about the prognostic value of miR-146a-5p. A comprehensive meta-analysis was conducted. Twelve platforms in miRWalk 2.0 were applied to predict targets of miR-146a-5p. TCGA RNA-seq data were used to validate the inverse relationships between miR-146a-5p and its likely targets. Subsequently, gene ontology and pathway analyses were conducted using Funrich version 3.1.3. Potential protein–protein interaction (PPI) networks were constructed. Potential target genes of miR-146a-5p in lung cancer were validated by RT-qPCR.

Results

We included 10 articles in the meta-analysis. In a pooled analysis, the high miR-146a-5p expression group showed a better overall survival in solid cancers, particularly in reproductive system cancers and digestive system cancers. A total of 120 predicted target genes were included in a bioinformatics analysis. Five pathways involving phospholipase C (PLC) and aquaporins (AQPs) were the most significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways. Moreover, the PPI network displayed the related signaling pathways and interactions among proteins. AQP1 and FYN were validated by RT-qPCR to be potential targets of miR-146a-5p in lung cancer.

Conclusion

There is a close link between high miR-146a-5p expression and better overall survival in 21 types of solid cancer, especially in reproductive system and digestive system cancers. Furthermore, miR-146a-5p could inhibit diverse malignancies by modulating pathways linked to PLC or AQPs. In summary, miR-146a-5p is a potential prognostic biomarker and therapeutic target for various cancers.

MicroRNA-146b Overexpression Promotes Human Bladder Cancer Invasion via Enhancing ETS2-Mediated mmp2 mRNA Transcription

Although microRNAs have been validated to play prominent roles in the occurrence and development of human bladder cancer (BC), alterations and function of many microRNAs (miRNAs) in bladder cancer invasion are not fully explored yet. miR-146b was reported to be a tumor suppressor or oncomiRNA in various types of cancer. However, its accurate expression, function, and mechanism in bladder cancer remain unclear. Here we discovered that miR-146b was frequently upregulated in bladder cancer tissues compared with adjacent non-cancerous tissues. Inhibition of miR-146b resulted in a significant inhibitory effect on the invasion of bladder cancer cells by reducing mmp2 mRNA transcription and protein expression. We further demonstrated that knockdown of miR-146b attenuated ETS2 expression, which was the transcription factor of matrix metalloproteinase (MMP)2. Moreover, mechanistic studies revealed that miR-146b inhibition stabilized ARE/poly(U)-binding/degradation factor 1 (auf1) mRNA by directly binding to its mRNA 3′ UTR, further reduced ets2 mRNA stability, and finally inhibited mmp2 transcription and attenuated bladder cancer invasion abilities. The identification of the miR-146b/AUF1/ETS2/MMP2 mechanism for promoting bladder cancer invasion provides significant insights into understanding the nature of bladder cancer metastasis. Targeting the pathway described here may be a novel approach for inhibiting invasion and metastasis of bladder cancer.

miR-146a-5p: Expression, regulation, and functions in cancer

Cancer as we know it is actually an umbrella term for over 100 very unique malignancies in various tissues throughout the human body. Each type, and even subtype of cancer, has different genetic, epigenetic, and other cellular events responsible for malignant development and metastasis. Recent work has indicated that microRNAs (miRNAs) play a major role in these processes, sometimes by promoting cancer growth and other times by suppressing tumorigenesis. miRNAs are small, noncoding RNAs that negatively regulate expression of specific target genes. This review goes into an in-depth look at the most recent finding regarding the significance of one particular miRNA, miR-146a-5p, and its involvement in cancer. Target gene validation and pathway analysis have provided mechanistic insight into this miRNA's purpose in assorted tissues. Additionally, this review outlines novel findings that suggest miR-146a-5p may be useful as a noninvasive biomarker and as a targeted therapeutic in several cancers. This article is categorized under: RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs.

p16INK4a inhibits the proliferation of osteosarcoma cells through regulating the miR-146b-5p/TRAF6 pathway

Down-regulation of p16INK4a and miR-146b-5p contributes to tumorigenesis in osteosarcoma (OS). However, the correlation between p16INK4a and miR-146b-5p in OS proliferation remains largely unknown. In the present study, we demonstrated that miR-146b-5p expression was positively correlated with p16INK4a in OS, but inversely correlated with TNF receptor associated factor 6 (TRAF6) expression. Overexpression of miR-146b-5p dramatically suppressed OS cell proliferation. Mechanistically, we validated TRAF6 as a direct functional target of miR-146b-5p and found that miR-146b-5p overexpression significantly decreased the level of phosphorylated PI3k and Akt, which are the pivotal downstream effectors of TRAF6. Moreover, TRAF6 expression was positively correlated with Ki-67 but inversely correlated with miR-146b-5p expression. In OS cells, silencing of TRAF6 mimicked the anti-tumor effects of miR-146b-5p. p16INK4a is an important tumor suppressor gene frequently down-regulated in OS. We found that this inhibitory effect is associated with the suppression of the miR-146b-5p, and is mediated via up-regulating TRAF6 expression. Our findings identified p16INK4a and miR-146b-5p as tumor suppressors, and suggested p16INK4a, miR-146b-5p and TRAF6 as potential therapeutic candidates for malignant OS.

Inhibition of miR146b-5p suppresses CT-guided renal cell carcinoma by targeting TRAF6

Renal cell carcinoma (RCC) is one of the most common malignancies in the urinary system. Due to the lack of early symptoms, diagnosis of RCC usually occurs at late stages or after cancer metastasis leading to poor prognosis. Therefore, it is crucial to study early molecular mechanisms and biomarkers. Previous studies have suggested that microRNAs are involved in RCC initiation and development, making them a good candidate for early diagnosis and therapy. MiR146b-5P plays important roles in the progression of multiple cancers including thyroid cancer, pancreatic cancer, cervical cancer. However, it is not clear whether and how miR146b-5P is involved in RCC. In this study, we aimed to investigate the function of miR146b-5P in RCC. We examined the expression levels of miR146b-5p in renal cancer tissue and cell lines. We also explored the effects of blocking miR146b-5p in renal tumor growth and inflammatory signaling. Finally, we determined if miR146b-5p regulates tumorigenesis through TRAF6. We found that miR146b-5p levels were significantly increased in renal cancer tissue and renal cancer cells. Blocking miR146b-5p suppressed renal tumor growth and enhanced inflammatory response through increased TRAF6 expression. These effects were eliminated in TRAF6 knockout mice. Our results suggest that enhanced miR146b-5p expression may be a biomarker for RCC and modulating miR146b-5p and TRAF6 levels represent a potential therapeutic strategy for RCC.

miR-124 regulates EMT based on ZEB2 target to inhibit invasion and metastasis in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is highly invasive and aggressive and lacks specific molecular targets to improve the prognosis. MicroRNAs (miRNAs) serve a role in promoting and suppressing tumors in various types of malignant cancer, including TNBC. However, the regulatory mechanism of miR-124 in TNBC has still remains unclear.

METHODS

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of miR-124. Cell viability was analyzed with CCK-8 assay. Cell colony formation ability was detected with colony formation assay. Cell invasion was measured with transwell assay. Dual luciferase reporter assay was conducted to verify whether ZEB2 is a target gene of miR-124. The mRNA and protein expression levels of ZEB2 and EMT markers were detected by quantitative real time PCR and western blot, respectively.

RESULTS

Our results showed that miR-124 was down-regulated in TNBC tissues and cells. Overexpression of miR-124 inhibited the proliferation, metastasis and epithelial-mesenchymal transition (EMT) of TNBC cells. Furthermore, ZEB2 3'UTR was considered to be a direct target of miR-124 with luciferase reporter assay. Rescue experiments confirmed that EMT was regulated by miR-124 via suppression of ZEB2.

CONCLUSION

miR-124 suppresses EMT and metastasis via ZEB2. Therefore, miR-124 may represent a potential therapeutic target for TNBC.

Role of micro-RNAs in breast cancer surgery

BACKGROUND

The management of breast cancer has changed dramatically in the molecular era. Micro-RNAs can contribute to multiple facets of cancer surgery.

METHODS

This narrative review, based on years of research on the role of micro-RNAs, focused on the potential of these small, robust RNAs to influence all aspects of breast cancer surgery.

RESULTS

Micro-RNAs have a potential role as biomarkers in the diagnosis, prognosis and evaluation of response to therapy in breast cancer. They may also contribute to future therapeutic strategies.

CONCLUSION

The molecular era has changed understanding of cancer. Micro-RNAs have the potential for use in personalized cancer strategies.

MicroRNA-146b-3p Promotes Cell Metastasis by Directly Targeting NF2 in Human Papillary Thyroid Cancer

Background: MiR-146b has been reported to be overexpressed in papillary thyroid cancer (PTC) tissues and associated with aggressive PTC. MiR-146b is regarded as a relevant diagnostic marker for this type of cancer. MiR-146b-5p has been confirmed to increase cell proliferation by repressing SMAD4. However, detailed functional analysis of another mature form of miR-146b, miR-146b-3p, has not been carried out. This study aimed to identify the differential expression of miR-146b-5p and miR-146b-3p in more aggressive PTC associated with lymph node metastasis, and further elucidate the contribution and mechanism of miR-146b-3p in the process of PTC metastasis. Methods: Expression of miR-146b-5p and miR-146b-3p was assessed in formalin-fixed paraffin-embedded tissue samples from PTC patients, and the relationship with lymph node metastasis was analyzed. A variety of PTC cells, including BHP10-3, BHP10-3SC_mice, and K1 cells, were cultured and treated with miR-146b-5p or miR-146b-3p mimics/inhibitors. The cell migration and invasion abilities were characterized by the real-time cell analyzer assay and Transwell™ assay. PTC xenograft models were used to examine the effect of miR-146b-3p on PTC metastatic ability in vivo. Direct downstream targets of miR-146b-3p were analyzed by luciferase reporter assay and Western blotting. The mechanism by which miR-146b-3p affects cell metastasis was further characterized by co-transfection with merlin, the protein product of the NF2 gene. Results: MiR-146b-5p and miR-146b-3p expression was significantly higher in thyroid cancer tissues and cell lines than in normal thyroid tissue and cells. Moreover, expression of miR-146b-5p and miR-146b-3p was further increased in thyroid metastatic nodes than in thyroid cancer. After overexpression of miR-146b-5p or miR-146b-3p in BHP10-3 or K1 cells, PTC migration and invasion were increased. Notably, miR-146b-3p increased cell migration and invasion more obviously than did miR-146b-5p. Overexpression of miR-146b-3p also significantly promoted PTC tumor metastasis in vivo. Luciferase reporter assay results revealed that NF2 is a downstream target of miR-146b-3p in PTC cells, as miR-146b-3p bound directly to the 3' untranslated region of NF2, thus reducing protein levels of NF2. Overexpression of merlin reversed the enhanced aggressive effects of miR-146b-3p. Conclusions: Overexpression of miR-146b-5p and miR-146b-3p is associated with PTC metastasis. MiR-146b-3p enhances cell invasion and metastasis more obviously than miR-146b-5p through the suppression of the NF2 gene. These findings suggest a potential diagnostic and therapeutic value of these miRNAs in PTC metastasis.

Association of MicroRNA Polymorphisms With Hepatocellular Carcinoma in an Iranian Population

Background

Single nucleotide polymorphisms (SNPs) can modulate various biological processes by influencing microRNA (miRNA) biogenesis and altering target selection. Common SNPs may alter the processing of miRNA and may be associated with hepatocellular carcinoma (HCC). We investigated the relationship between miR-499A>G, miR-149C>T, miR-196a2T>C, and miR-146aG>C and HCC susceptibility, examining the interaction of the miRNAs with hepatitis B virus (HBV).

Methods

We evaluated the associations of miR-499A>G (rs3746444), miR-149C>T (rs2292832), miR-196a2T>C (rs11614913), and miR-146aG>C (rs2910164) with HCC susceptibility in 100 HCC patients (70 males and 30 females) and 120 healthy controls (70 males and 50 females), using the PCR-restriction fragment length polymorphism method.

Results

For miR-499A>G, the frequencies of the AG genotype and G allele were higher in female HCC patients than in female controls (P=0.02 and 0.045, respectively). The frequency of the A allele was higher in HBV-positive HCC patients than in controls (P=0.019). For miR-149C>T, the frequency of the CC genotype was higher in female HCC patients than in female controls (P=0.009). For miR-196a2T>C, the frequencies of the CT and CC genotypes and the C allele were higher in HBV-positive HCC patients than in controls (P<0.001, P=0.009, and P<0.001, respectively). The frequencies of miR-146aG>C polymorphisms did not differ between HCC patients and controls.

Conclusions

miR-499A>G, miR-149C>T, and miR-196a2T>C were associated with the development of HCC in women and/or that of HBV-related HCC. They can be considered genetic risk factors for the development of HCC among Iranians.

Identifying a miRNA signature for predicting the stage of breast cancer

Breast cancer is a heterogeneous disease and one of the most common cancers among women. Recently, microRNAs (miRNAs) have been used as biomarkers due to their effective role in cancer diagnosis. This study proposes a support vector machine (SVM)-based classifier SVM-BRC to categorize patients with breast cancer into early and advanced stages. SVM-BRC uses an optimal feature selection method, inheritable bi-objective combinatorial genetic algorithm, to identify a miRNA signature which is a small set of informative miRNAs while maximizing prediction accuracy. MiRNA expression profiles of a 386-patient cohort of breast cancer were retrieved from The Cancer Genome Atlas. SVM-BRC identified 34 of 503 miRNAs as a signature and achieved a 10-fold cross-validation mean accuracy, sensitivity, specificity, and Matthews correlation coefficient of 80.38%, 0.79, 0.81, and 0.60, respectively. Functional enrichment of the 10 highest ranked miRNAs was analysed in terms of Kyoto Encyclopedia of Genes and Genomes and Gene Ontology annotations. Kaplan-Meier survival analysis of the highest ranked miRNAs revealed that four miRNAs, hsa-miR-503, hsa-miR-1307, hsa-miR-212 and hsa-miR-592, were significantly associated with the prognosis of patients with breast cancer.