Role of miR-10b in breast cancer metastasis

MicroRNAs as promising biomarkers and potential therapeutic agents in breast cancer management: a comprehensive review

Breast cancer (BC), a complex and varied ailment, poses a significant global health burden. MicroRNAs (miRNAs) have emerged as vital regulators in BC progression, with potential implications for diagnosis and treatment. This review aims to synthesize current insights into miRNA dysregulation in BC. MiRNAs, small RNA molecules, govern gene expression post-transcriptionally and are implicated in BC initiation, metastasis, and therapy resistance. Differential expression of specific miRNAs in BC tissues versus normal breast tissue sheds light on underlying molecular mechanisms. MiRNAs also offer promise as diagnostic biomarkers due to their stable nature, accessibility in bodily fluids, and altered expression patterns in early-stage disease, augmenting conventional diagnostic methods. Beyond diagnosis, miRNAs also hold promise as therapeutic targets in BC. By modulating the expression of specific dysregulated miRNAs, it may be possible to restore normal cellular functions and overcome treatment resistance. However, several challenges need to be addressed before miRNA-based therapies can be translated into clinical practice, including the development of efficient delivery systems and rigorous evaluation through preclinical and clinical trials. MiRNAs represent a promising avenue in BC research, offering potential applications in diagnosis, prognosis, and therapeutic interventions. As our understanding of miRNA biology deepens and technology advances, further research and collaborative efforts are needed to fully exploit the diagnostic and therapeutic potential of miRNAs in BC management. Ultimately, the integration of miRNA-based approaches into clinical practice may lead to more personalized and effective strategies for combating this devastating disease.

A cubic DNA nanocage probe for in situ analysis of miRNA-10b in tumor-derived extracellular vesicles

A cubic DNA nanocage probe is able to enter EVs derived from MDA-MB-231 cells and react with miRNA-10b. The probe-loaded EVs were employed to monitor the process of entry of miRNA-10b into MCF-10A cells, allowing visualization of EV-mediated intercellular communication of miRNA-10b between the cancer cells.

The Killer's Web: Interconnection between Inflammation, Epigenetics and Nutrition in Cancer

Inflammation is a key contributor to both the initiation and progression of tumors, and it can be triggered by genetic instability within tumors, as well as by lifestyle and dietary factors. The inflammatory response plays a critical role in the genetic and epigenetic reprogramming of tumor cells, as well as in the cells that comprise the tumor microenvironment. Cells in the microenvironment acquire a phenotype that promotes immune evasion, progression, and metastasis. We will review the mechanisms and pathways involved in the interaction between tumors, inflammation, and nutrition, the limitations of current therapies, and discuss potential future therapeutic approaches.

Circulating miR-10b, soluble urokinase-type plasminogen activator receptor, and plasminogen activator inhibitor-1 as predictors of non-small cell lung cancer progression and treatment response

BACKGROUND

Despite advances in lung cancer treatment, most lung cancers are diagnosed at an advanced stage. Expression of microRNA10b (miR-10b) and fibrinolytic activity, as reflected by soluble urokinase-type plasminogen activator receptor (suPAR) and plasminogen activator inhibitor 1 (PAI-1), are promising biomarker candidates.

OBJECTIVE

To assess the expression of miR-10b, and serum levels of suPAR and PAI-1 in advanced stage non-small cell lung cancer (NSCLC) patients, and their correlation with progression, treatment response and prognosis.

METHODS

The present prospective cohort and survival study was conducted at Dharmais National Cancer Hospital and included advanced stage NSCLC patients diagnosed between March 2015 and September 2016. Expression of miR-10b was quantified using qRT-PCR. Levels of suPAR and PAI-1 were assayed using ELISA. Treatment response was evaluated using the RECIST 1.1 criteria. Patients were followed up until death or at least 1 year after treatment.

RESULTS

Among the 40 patients enrolled, 25 completed at least four cycles of chemotherapy and 15 patients died during treatment. Absolute miR-10b expression ⩾ 592,145 copies/μL or miR-10b fold change ⩾ 0.066 were protective for progressive disease and poor treatment response, whereas suPAR levels ⩾ 4,237 pg/mL was a risk factor for progressive disease and poor response. PAI-1 levels > 4.6 ng/mL was a protective factor for poor response. Multivariate analysis revealed suPAR as an independent risk factor for progression (ORa⁢d⁢j, 13.265; 95% confidence intervals (CI), 2.26577.701; P= 0.006) and poor response (ORa⁢d⁢j, 15.609; 95% CI, 2.221-109.704; P= 0.006), whereas PAI-1 was an independent protective factor of poor response (ORa⁢d⁢j, 0.127; 95% CI, 0.019-0.843; P= 0.033).

CONCLUSIONS

Since miR-10b cannot be used as an independent risk factor for NSCLC progression and treatment response, we developed a model to predict progression using suPAR levels and treatment response using suPAR and PAI-1 levels. Further studies are needed to validate this model.

Differential microRNAs Expression during Cancer Development, and Chemoprevention by Natural Compounds: A Comprehensive Review

MicroRNAs are short non-coding RNAs that inhibit gene expression at the post-transcriptional level. Abnormal microRNA expression has been associated with different human diseases, including cancer. Epigenetic changes, mutation, transcriptional deregulation, DNA copy number abnormalities, and defects in the biogenesis machinery play an important role in abnormal microRNA expression. Modulation of microRNAs by natural agents has emerged to enhance the efficacy of conventional chemotherapy through combinatorial therapeutic approach. This review summarizes the current understanding of abnormal microRNA expression in cancer, the different cellular mechanisms of microRNA, and their prevention by natural compounds. Understanding microRNA expression patterns during cancer development may help to identify stage-specific molecular markers. Natural compounds that exert regulatory effects by modulating microRNAs can be used in better cancer chemopreventive strategies by directly targeting microRNAs or as a way to increase sensitivity to existing chemotherapy regimens.

New insights of miRNA molecular mechanisms in breast cancer brain metastasis and therapeutic targets

Brain metastases in breast cancer (BC) patients are often associated with a poor prognosis. Recent studies have uncovered the critical roles of miRNAs in the initiation and progression of BC brain metastasis, highlighting the disease's underlying molecular pathways. miRNA-181c, miRNA-10b, and miRNA-21, for example, are all overexpressed in BC patients. It has been shown that these three miRNAs help tumors grow and metastasize by targeting genes that control how cells work. On the other hand, miRNA-26b5p, miRNA-7, and miRNA-1013p are all downregulated in BC brain metastasis patients. They act as tumor suppressors by controlling the expression of genes related to cell adhesion, angiogenesis, and invasion. Therapeutic miRNA targeting has considerable promise in treating BC brain metastases. Several strategies have been proposed to modulate miRNA expression, including miRNA-Mimics, antagomirs, and small molecule inhibitors of miRNA biogenesis. This review discusses the aberrant expression of miRNAs and metastatic pathways that lead to the spread of BC cells to the brain. It also explores miRNA therapeutic target molecular mechanisms and BC brain metastasis challenges with advanced strategies. The targeting of certain miRNAs opens a new door for the development of novel therapeutic approaches for this devastating disease.

Circulating microRNAs can predict chemotherapy-induced toxicities in patients being treated for primary breast cancer

PURPOSE

Prescribing NAC for breast cancer is a pragmatic treatment strategy for several reasons; however, certain patients suffer chemotherapy-induced toxicities. Unfortunately, identifying patients at risk of toxicity often proves challenging. MiRNAs are small non-coding RNA molecules which modulate genetic expression. The aim of this study was to determine whether circulating miRNAs are sensitive biomarkers that can identify the patients likely to suffer treatment-related toxicities to neoadjuvant chemotherapy (NAC) for primary breast cancer.

METHODS

This secondary exploratory from the prospective, multicentre translational research trial (CTRIAL ICORG10/11-NCT01722851) recruited 101 patients treated with NAC for breast cancer, from eight treatment sites across Ireland. A predetermined five miRNAs panel was quantified using RQ-PCR from patient bloods at diagnosis. MiRNA expression was correlated with chemotherapy-induced toxicities. Regression analyses was performed using SPSS v26.0.

RESULTS

One hundred and one patients with median age of 55 years were recruited (range: 25-76). The mean tumour size was 36 mm and 60.4% had nodal involvement (n = 61) Overall, 33.7% of patients developed peripheral neuropathies (n = 34), 28.7% developed neutropenia (n = 29), and 5.9% developed anaemia (n = 6). Reduced miR-195 predicted patients likely to develop neutropenia (P = 0.048), while increased miR-10b predicted those likely to develop anaemia (P = 0.049). Increased miR-145 predicted those experiencing nausea and vomiting (P = 0.019), while decreased miR-21 predicted the development of mucositis (P = 0.008).

CONCLUSION

This is the first study which illustrates the value of measuring circulatory miRNA to predict patient-specific toxicities to NAC. These results support the ideology that circulatory miRNAs are biomarkers with utility in predicting chemotherapy toxicity as well as treatment response.

microRNAs signature in relapse metastasis and de novo metastasis of breast cancer. A systematic review

miRNAs have been widely identified as important players in cancer development and progression. Metastasis in breast cancer can occur as relapse of a treated primary tumour or at the time of diagnosis of the tumour. The aim of this review is to show if both metastasis are different molecular entities characterised by different miRNA signatures that could be studied as specific biomarkers for each entity. For this, we systematically searched the PubMed, Scopus and Web of Science databases. After searching and reviewing the literature, a total of 30 records were included in this review. Results showed a genetic signature including a total of 5 upregulated miRNAs in metastasis compared with early stages. Of them, miR-23b and miR-200c were exclusively present in relapse metastasis. Finally, we proposed a molecular signature for future studies that can be used as a complementary tool at clinical trials for the diagnosis and characterization of metastasis.

An Overview of the Role of MicroRNAs on Carcinogenesis: A Focus on Cell Cycle, Angiogenesis and Metastasis

In recent years, the importance of epigenetic markers in the carcinogenesis of different malignant neoplasms has been demonstrated, also demonstrating their utility for understanding metastatic spread and tumor progression in cancer patients. Among the different biomarkers, microRNAs represent a set of non-coding RNAs that regulate gene expression, having been involved in a wide variety of neoplasia acting in different oncogenic pathways. Both the overexpression and downregulation of microRNAs represent a complex interaction with various genes whose ultimate consequence is increased cell proliferation, tumor invasion and interaction with various driver markers. It should be noted that in current clinical practice, even though the combination of different microRNAs has been shown to be useful by different authors at diagnostic and prognostic levels, there are no diagnostic kits that can be used for the initial approach or to assess recurrences of oncological diseases. Previous works have cited microRNAs as having a critical role in several carcinogenic mechanisms, ranging from cell cycle alterations to angiogenesis and mechanisms of distant metastatic dissemination. Indeed, the overexpression or downregulation of specific microRNAs seem to be tightly involved in the modulation of various components related to these processes. For instance, cyclins and cyclin-dependent kinases, transcription factors, signaling molecules and angiogenic/antiangiogenic products, among others, have been recognized as specific targets of microRNAs in different types of cancer. Therefore, the purpose of this article is to describe the main implications of different microRNAs in cell cycle alterations, metastasis and angiogenesis, trying to summarize their involvement in carcinogenesis.

Exosomal miRNAs as novel avenues for breast cancer treatment

Breast cancer is the most commonly diagnosed cancer and a leading cause of death in women worldwide. It is a heterogeneous disease, as shown by the gene expression profiles of breast cancer samples. It begins in milk-producing ducts, with a high degree of diversity between and within tumors, as well as among cancer-bearing individuals. The enhanced prevalence of breast cancer is influenced by various hormonal, lifestyle, and environmental factors, and very early onset of the disease correlates strongly with the risk of local and distant recurrence. Many subtypes are difficult to treat with conventional therapeutic modalities, and therefore, optimal management and early diagnosis are the first steps to minimizing the mortality linked with breast cancer. The use of newer methods of nanotechnology extends beyond the concept of synthesizing drug delivery mechanisms into the creation of new therapeutics, such as delivering chemotherapeutics with nanomaterial properties. Exosomes, a class of nanovesicles, are emerging as novel tools for deciphering the patient-specific proteins and biomarkers across different disease models, including breast cancer. In this review, we address the role of exosomal miRNA in breast cancer diagnosis and treatment.

An Overview of Epithelial-to-Mesenchymal Transition and Mesenchymal-to-Epithelial Transition in Canine Tumors: How Far Have We Come?

Historically, pre-clinical and clinical studies in human medicine have provided new insights, pushing forward the contemporary knowledge. The new results represented a motivation for investigators in specific fields of veterinary medicine, who addressed the same research topics from different perspectives in studies based on experimental and spontaneous animal disease models. The study of different pheno-genotypic contexts contributes to the confirmation of translational models of pathologic mechanisms. This review provides an overview of EMT and MET processes in both human and canine species. While human medicine rapidly advances, having a large amount of information available, veterinary medicine is not at the same level. This situation should provide motivation for the veterinary medicine research field, to apply the knowledge on humans to research in pets. By merging the knowledge of these two disciplines, better and faster results can be achieved, thus improving human and canine health.

The Significance of MicroRNAs in the Molecular Pathology of Brain Metastases

Brain metastases are the most frequent intracranial tumors in adults and the cause of death in almost one-fourth of cases. The incidence of brain metastases is steadily increasing. The main reason for this increase could be the introduction of new and more efficient therapeutic strategies that lead to longer survival but, at the same time, cause a higher risk of brain parenchyma infiltration. In addition, the advances in imaging methodology, which provide earlier identification of brain metastases, may also be a reason for the higher recorded number of patients with these tumors. Metastasis is a complex biological process that is still largely unexplored, influenced by many factors and involving many molecules. A deeper understanding of the process will allow the discovery of more effective diagnostic and therapeutic approaches that could improve the quality and length of patient survival. Recent studies have shown that microRNAs (miRNAs) are essential molecules that are involved in specific steps of the metastatic cascade. MiRNAs are endogenously expressed small non-coding RNAs that act as post-transcriptional regulators of gene expression and thus regulate most cellular processes. The dysregulation of these molecules has been implicated in many cancers, including brain metastases. Therefore, miRNAs represent promising diagnostic molecules and therapeutic targets in brain metastases. This review summarizes the current knowledge on the importance of miRNAs in brain metastasis, focusing on their involvement in the metastatic cascade and their potential clinical implications.

Review article epithelial to mesenchymal transition‑associated microRNAs in breast cancer

Despite major advances, breast cancer (BC) is the most commonly diagnosed carcinoma and remains a deadly disease among women worldwide. Many researchers point toward an important role of an epithelial to mesenchymal transition (EMT) in BC development and promoting metastasis. Here, will be discussed that how functional changes of transcription factors, signaling pathways, and microRNAs (miRNA) in BC promote EMT. A thorough understanding the EMT biology can be important to determine reversing the process and design treatment approaches. There are frequent debates as to whether EMT is really relevant to BC in vivo, in which due to the intrinsic heterogeneity and tumor microenvironment. Nevertheless, given the importance of EMT in cancer progression and metastasis, the implementation of therapies against cancer-associated EMT will continue to help us develop and test potential treatments.

Low miR-10b-3p associated with sorafenib resistance in hepatocellular carcinoma

BACKGROUND

Sorafenib is one of the standard first-line therapies for advanced hepatocellular carcinoma (HCC). Unfortunately, there are currently no appropriate biomarkers to predict the clinical efficacy of sorafenib in HCC patients. MicroRNAs (miRNAs) have been studied for their biological functions and clinical applications in human cancers.

METHODS

In this study, we found that miR-10b-3p expression was suppressed in sorafenib-resistant HCC cell lines through miRNA microarray analysis.

RESULTS

Sorafenib-induced apoptosis in HCC cells was significantly enhanced by miR-10b-3p overexpression and partially abrogated by miR-10b-3p depletion. Among 45 patients who received sorafenib for advanced HCC, those with high miR-10b-3p levels, compared to those with low levels, exhibited significantly longer overall survival (OS) (median, 13.9 vs. 3.5 months, p = 0.021), suggesting that high serum miR-10b-3p level in patients treated with sorafenib for advanced HCC serves as a biomarker for predicting sorafenib efficacy. Furthermore, we confirmed that cyclin E1, a known promoter of sorafenib resistance reported by our previous study, is the downstream target for miR-10b-3p in HCC cells.

CONCLUSIONS

This study not only identified the molecular target for miR-10b-3p, but also provided evidence that circulating miR-10b-3p may be used as a biomarker for predicting sorafenib sensitivity in patients with HCC.

Significance of metastamiR-10b in breast cancer therapeutics

Background

Breast cancer is a fatal disease and a major reason of cancer associated death in females. Many factors along with miRNA are responsible for the development and the progression of the disease. The miRNA plays a very crucial role in the regulation of the genes. MicroRNAs are of three major types—oncomiRs, tumor suppressive miRNAs, and metastamiRs.

Main body

MicoRNA-10b is a prometastatic microRNA targeting various genes that facilitates multiple outcomes such as metastasis, increased capacity for invasion, proliferation and migration, increased epithelial-mesenchymal transformation, angiogenesis, and therefore exhibits worse clinical outcomes. It is found to be upregulated in various malignancies and is thus to be considered as the possible therapeutic candidate.

Conclusion

The therapeutic delivery of miR-10b antagonists (antagomiRs) and/or knockdown of miRNA is beneficial in reducing tumor growth. Additionally, combination therapy which includes antisense oligonucleotides using miR-10b can function as an effective approach to tumor regression and drug resistance reversal.

Graphical abstract

MicroRNA 21 and microRNA 10b: early diagnostic biomarkers of breast cancer in Egyptian females

BACKGROUND

Breast cancer (BC) is one of the most prevalent cancers in developing and developed countries among women worldwide. Mammography is one of the superior methods for BC detection, but it carries up to 20% false-negative results, especially in early cases. Histological examination of tissue biopsies and fine-needle aspiration cytology are invasive techniques. Hence, minimally invasive markers are needed for the improved detection of BC. microRNAs, small, noncoding, single-stranded RNAs functioning as tumor suppressor genes or oncogenes, are attractive biomarkers for early detection. This study aimed to examine the serum levels of miR21 and miR10b in patients with BC especially in the early stages compared to healthy controls to evaluate their potential use as BC biomarkers.

METHODS

This study included 90 females who were divided into two groups. Group I included 70 patients with BC and was subdivided into group Ia with 40 nonmetastatic BC patients and group Ib with 30 metastatic BC patients. Group II included 20 apparently healthy females as a control group. Serum miR21 and miR10b as biomarkers and miR16 as a housekeeping gene were evaluated using real-time polymerase chain reaction.

RESULTS

The median levels of miR10b and miR21 were statistically significantly upregulated in the sera of patients with BC compared to healthy controls (P = 0.001). Receiver operating characteristic curve analyses demonstrated that serum levels of miR10b and miR21 were useful biomarkers for distinguishing between patients with BC and the control group, with an area under the curve (AUC) of 0.991 with 97.1% sensitivity and 100% specificity at a cutoff of 3.1 for miR10b and an AUC of 0.965 with 95.7% sensitivity and 85% specificity at a cutoff of 1.7 for miR21. Regarding the early stages of BC, the median levels of the fold change of serum miR21 and miR10b were statistically significantly higher in patients with BC (stages I and IIa) than in the control group (P < 0.001).

CONCLUSIONS

Both miR21 and miR10b have valuable diagnostic roles in detecting the early stages of BC.

Evaluation of Expressed MicroRNAs as Prospective Biomarkers for Detection of Breast Cancer

Background: Early detection and screening of breast cancer (BC) might help improve the prognosis of BC patients. This study evaluated the use of serum microRNAs (miRs) as non-invasive biomarkers in BC patients. Methods: Using quantitative real-time polymerase chain reaction, we evaluated the serum expression of four candidate miRs (miR-155, miR-373, miR-10b, and miR-34a) in 99 Egyptian BC patients and 40 healthy subjects (as a control). The miRs expression was correlated with clinicopathological data. In addition, the sensitivity and specificity of the miRs were determined using receiver operating characteristic (ROC) curve analysis. Results: Serum miR-155, miR-373, and miR-10b expression were significantly upregulated (p < 0.001), while serum miR-34a was downregulated (p < 0.00) in nonmetastatic (M0) BC patients compared to the control group. In addition, serum miR-155 and miR-10b were upregulated in BC patients with large tumor sizes and extensive nodal involvement (p < 0.001). ROC curve analysis showed high diagnostic accuracy (area under the curve = 1.0) when the four miRs were combined. Serum miR-373 was significantly upregulated in the human epidermal growth factor 2−negative (p < 0.001), estrogen receptor−positive (p < 0.005), and progesterone receptor (PR)-positive (p < 0.024) in BC patients, and serum miR-155 was significantly upregulated in PR-negative (p < 0.001) BC patients while both serum miR-155 and miR-373 were positively correlated with the tumor grade. Conclusions: Circulating serum miR-155, miR-373, miR-10b, and miR-34a are potential biomarkers for early BC detection in Egyptian patients and their combination shows high sensitivity and specificity.

MicroRNA editing patterns in Huntington's disease

Huntington’s disease (HD) is a neurodegenerative disease. MicroRNAs (miRNAs) are small non-coding RNAs that mediate post-transcriptional regulation of target genes. Although miRNAs are extensively edited in human brains, the editome of miRNAs in brains of HD patients is largely unknown. By analyzing the small RNA sequencing profiles of brain tissues of 28 HD patients and 83 normal controls, 1182 miRNA editing sites with significant editing levels were identified. In addition to 27 A-to-I editing sites, we identified 3 conserved C-to-U editing sites in miRNAs of HD patients. 30 SNPs in the miRNAs of HD patients were also identified. Furthermore, 129 miRNA editing events demonstrated significantly different editing levels in prefrontal cortex samples of HD patients (HD-PC) when compared to those of healthy controls. We found that hsa-mir-10b-5p was edited to have an additional cytosine at 5’-end in HD-PC, and the edited hsa-mir-10b repressed GTPBP10 that was often downregulated in HD. The down-regulation of GTPBP10 might contribute to the progression of HD by causing gradual loss of function of mitochondrial. These results provide the first endeavor to characterize the miRNA editing events in HD and their potential functions.

Blood Circulating Non-Coding RNAs for the Clinical Management of Triple-Negative Breast Cancer

Triple negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer, and is related to unfavorable prognosis and limited treatment strategies. Currently, there is a lack of reliable biomarkers allowing for the clinical management of TNBC. This is probably caused by a complex molecular background, leading to the development and establishment of a unique tumor phenotype. Recent studies have reported non-coding RNAs (ncRNAs) not only as the most promising class of molecular agents with a high applicability to manage human cancers, including TNBC, but also as robust and non-invasive biomarkers that are able to be monitored in blood circulation, with the application of liquid biopsy. There is a lack of papers discussing the role of blood-circulating ncRNAs as diagnostic, predictive, and prognostic biomarkers for TNBC. In this paper, we summarized the available literature reports on the utility of blood-circulating ncRNAs for TNBC management. Additionally, we supplemented this review by bioinformatics analysis, for better understanding of the role of ncRNAs' machinery in the development of a unique TNBC phenotype.

Preclinical Imaging Evaluation of miRNAs' Delivery and Effects in Breast Cancer Mouse Models: A Systematic Review

BACKGROUND

We have conducted a systematic review focusing on the advancements in preclinical molecular imaging to study the delivery and therapeutic efficacy of miRNAs in mouse models of breast cancer.

METHODS

A systematic review of English articles published in peer-reviewed journals using PubMed, EMBASE, BIOSIS™ and Scopus was performed. Search terms included breast cancer, mouse, mice, microRNA(s) and miRNA(s).

RESULTS

From a total of 2073 records, our final data extraction was from 114 manuscripts. The most frequently used murine genetic background was Balb/C (46.7%). The most frequently used model was the IV metastatic model (46.8%), which was obtained via intravenous injection (68.9%) in the tail vein. Bioluminescence was the most used frequently used tool (64%), and was used as a surrogate for tumor growth for efficacy treatment or for the evaluation of tumorigenicity in miRNA-transfected cells (29.9%); for tracking, evaluation of engraftment and for response to therapy in metastatic models (50.6%).

CONCLUSIONS

This review provides a systematic and focused analysis of all the information available and related to the imaging protocols with which to test miRNA therapy in an in vivo mice model of breast cancer, and has the purpose of providing an important tool to suggest the best preclinical imaging protocol based on available evidence.

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.

LentiRILES, a miRNA-ON sensor system for monitoring the functionality of miRNA in cancer biology and therapy

A major unresolved challenge in miRNA biology is the capacity to monitor the spatiotemporal activity of miRNAs expressed in animal disease models. We recently reported that the miRNA-ON monitoring system called RILES (RNAi-inducible expression Luciferase system) implanted in lentivirus expression system (LentiRILES) offers unique opportunity to decipher the kinetics of miRNA activity in vitro, in relation with their intracellular trafficking in glioblastoma cells. In this study, we describe in detail the method for the production of LentiRILES stable cell lines and employed it in several applications in the field of miRNA biology and therapy. We show that LentiRILES is a robust, highly specific and sensitive miRNA sensor system that can be used in vitro as a single-cell miRNA monitoring method, cell-based screening platform for miRNA therapeutics and as a tool to analyse the structure-function relationship of the miRNA duplex. Furthermore, we report the kinetics of miRNA activity upon the intracranial delivery of miRNA mimics in an orthotopic animal model of glioblastoma. This information is exploited to evaluate the tumour suppressive function of miRNA-200c as locoregional therapeutic modality to treat glioblastoma. Our data provide evidence that LentiRILES is a robust system, well suited to resolve the activity of endogenous and exogenously expressed miRNAs from basic research to gene and cell therapy.

Potential value of circulatory microRNA10b gene expression and its target E-cadherin as a prognostic and metastatic prediction marker for breast cancer

Background

Breast cancer (BC) is the leading cause of cancer death in women worldwide. Most BC studies on candidate microRNAs were tissue specimen based. Recently, there has been a focus on the study of cell‐free circulating miRNAs as promising biomarkers in (BC) diagnosis and prognosis. Therefore, we aimed to investigate the circulating levels of miR‐10b and its target soluble E‐ cadherin as potentially easily accessible biomarkers for breast cancer.

Methods

Sixty‐one breast cancer patients and forty‐eight age‐ and sex‐matched healthy volunteers serving as a control group were enrolled in the present study. Serum samples were used to assess miRNA10b expression by TaqMan miRNA assay technique. In addition, soluble E‐cadherin expression level in serum was determined using ELISA technique.

Result

Circulating miR‐10b expression level and serum sE‐cadherin was significantly upregulated in patients with BC compared to controls. Moreover, serum miR‐10b displayed progressive up‐regulation in advanced stages with higher level in metastatic compared to non‐metastatic BC. Additionally, the combined use of both serum miR‐10b and sE‐cadherin revealed the highest sensitivity and specificity for detection of BC metastasis (92.9% and 97.9% respectively) with an area under curve (AUC) of 0.98, 95% CI (0.958–1.00).

Conclusion

Our data suggest that circulating miR‐10b could be utilized as a potential non‐invasive serum biomarker for diagnosis and prognosis of breast cancer with better performance to predict BC metastasis achieved on measuring it simultaneously with serum sE‐cadherin. Further studies with a large cohort of patients are warranted to validate the serum biomarker for breast cancer management.

FOXO3a inhibits the EMT and metastasis of breast cancer by regulating TWIST-1 mediated miR-10b/CADM2 axis

BACKGROUND

Breast cancer is the most common malignancy and has been considered as a leading cause of cancer death in women. Exploring the mechanism of breast cancer metastasis is extremely important for seeking novel therapeutic strategies and improving prognosis.

METHODS

Clinical specimens and pathological characteristics were collected for evaluating the expression of forkhead box class O 3a (FOXO3a) and twist-related protein 1 (TWIST-1) in breast cancer tissues. CCK-8 assay was used to analyze cell proliferation. Cell invasion and migration were assessed by transwell assays. The expression of FOXO3a, TWIST-1, miR-10b, CADM2, FAK, phosphor-AKT and the epithelial-mesenchymal transition (EMT)-related protein (N-cadherin, E-cadherin and vimentin) were analyzed by RT-qPCR, immunohistochemical staining, immunofluorescence assay or western blot, respectively. Xenograft mouse models were used to analyze the role of the FOXO3a in breast cancer.

RESULTS

FOXO3a was down-regulated and TWIST-1 was up-regulated in breast cancer tissues. Overexpression of FOXO3a or knockdown of TWIST-1 suppressed the proliferation, invasion, migration and EMT of breast cancer cells. Overexpression of TWIST-1 could reverse the effect of FOXO3a on the proliferation, invasion, migration and EMT of breast cancer. Moreover, FOXO3a suppressed the growth and metastasis of breast cancer by targeting TWIST1 in vivo.

CONCLUSION

FOXO3a inhibited the EMT and metastasis of breast cancer via TWIST-1/miR-10b/CADM2 axis.

Exosomal microRNAs: Pleiotropic Impacts on Breast Cancer Metastasis and Their Clinical Perspectives

As a major threat factor for female health, breast cancer (BC) has garnered a lot of attention for its malignancy and diverse molecules participating in its carcinogenesis process. Among these complex carcinogenesis processes, cell proliferation, epithelial-to-mesenchymal transition (EMT), mesenchymal-to-epithelial transition (MET), and angiogenesis are the major causes for the occurrence of metastasis and chemoresistance which account for cancer malignancy. MicroRNAs packaged and secreted in exosomes are termed "exosomal microRNAs (miRNAs)". Nowadays, more researches have uncovered the roles of exosomal miRNAs played in BC metastasis. In this review, we recapitulated the dual actions of exosomal miRNAs exerted in the aggressiveness of BC by influencing migration, invasion, and distant metastasis. Next, we presented how exosomal miRNAs modify angiogenesis and stemness maintenance. Clinically, several exosomal miRNAs can govern the transformation between drug sensitivity and chemoresistance. Since the balance of the number and type of exosomal miRNAs is disturbed in pathological conditions, they are able to serve as instructive biomarkers for BC diagnosis and prognosis. More efforts are needed to connect the theoretical studies and clinical traits together. This review provides an outline of the pleiotropic impacts of exosomal miRNAs on BC metastasis and their clinical implications, paving the way for future personalized drugs.

Crosstalk between miRNAs and signaling pathways involved in pancreatic cancer and pancreatic ductal adenocarcinoma

Pancreatic cancer (PC) is the seventh leading cause of cancer-related deaths worldwide with 5-year survival rates below 8%. Most patients with PC and pancreatic ductal adenocarcinoma (PDAC) die after relapse and cancer progression as well as resistance to treatment. Pancreatic tumors contain a high desmoplastic stroma that forms a rigid mass and has a potential role in tumor growth and metastasis. PC initiates from intraepithelial neoplasia lesions leading to invasive cancer through various pathways. These lesions harbor particular changes in signaling pathways involved in the tumorigenesis process. These events affect both the epithelial cells, including the tumor and the surrounding stroma, and eventually lead to the formation of complex signaling networks. Genetic studies of PC have revealed common molecular features such as the presence of mutations in KRAS gene in more than 90% of patients, as well as the inactivation or deletion mutations of some tumor suppressor genes including TP53, CDKN2A, and SMAD4. In recent years, studies have also identified different roles of microRNAs in PC pathogenesis as well as their importance in PC diagnosis and treatment, and their involvement in various signaling pathways. In this study, we discussed the most common pathways involved in PC and PDAC as well as their role in tumorigenesis and progression. Furthermore, the miRNAs participating in the regulation of these signaling pathways in PC progression are summarized in this study. Therefore, understanding more about pathways involved in PC can help with the development of new and effective therapies in the future.

MicroRNA-205-5p targets the HOXD9-Snail1 axis to inhibit triple negative breast cancer cell proliferation and chemoresistance

MicroRNA-205 (miR-205) is believed to be related to the progress of tumors. HOXD9 has been proved to be expressed abnormally in several kinds of cancers. However, the role of miR-205 and HOXD9 in breast cancer remains unclear. The biological role of miR-205 in breast cancer cell proliferation and chemoresistance was investigated. The expression of miR-205 in clinical tissues and breast cancer cell lines were analyzed using quantitative real-time PCR test (qRT-PCR). Overexpression and knockdown models of miR-205 were established to study cell proliferation and chemotherapy-resistant. Moreover, the potential relationships between miR-205 and HOXD9/Snail1 were measured using qRT-PCR, western blot, and chemotherapy-resistant study. miR-205 was lowly expressed in breast cancer tissues and cell lines. Overexpression of miR-205 could inhibit cell proliferation and chemotherapy-resistance. Moreover, we proved that miR-205 could target the HOXD9-Snail1 axis to suppress triple negative breast cancer cell proliferation and chemoresistance. The activation of Snail1 gene by HOXD9 was also proved in this study. The present study may provide a novel insight for the therapeutic strategies of breast cancer through targeting miR-205/HOXD9/Snail1.

Differences of time-dependent microRNA expressions in breast cancer cells

MicroRNA (miRNA) expression is a dynamic process in the cell, and the proper time period for post-transcriptional regulation might be critical due to the gene-on/-off expression times of the cell. Here, we investigated the effect of different time-points on proliferation, invasion and miRNA expression profiles of human breast cancer cell lines MCF-7 (non-metastatic, epithelium-like breast cancer cell line with oestrogen receptor (ER) positive (+) and human breast cancer cell lines MDA-MB-435 (metastatic, invasive, ER negative (-). For this purpose, MCF-7 and MDA-MB-435 cells were seeded different number in E-plate 16 for proliferation experiment using an electrical impedance-based real-time cell analyzer system (RTCA) for 168 h. Similarly, invasion potential of MCF-7 and MDA-MB-435 were determined by RTCA for 90 h. Total RNAs including miRNAs were isolated at 2, 4, 6, 12, 24, 48 h from the MCF-7 and MDA-MB-435 cells. Afterward, the quantitative 84 miRNA expressions of MCF-7 and MDA-MB-435 were analyzed by Fluidigm Microfluidic 96.96 Dynamic Array. The results of these study demonstrated that both proliferation potential and invasion capacity of MDA-MB-435 is higher than MCF-7 as time-dependent manner. Furthermore, we detected that up/down expressions of 32 miRNAs at all time points in MDA-MB-435 compared to MCF-7 (at least ten-fold increased). Because of the high number of miRNAs, we more closely evaluated the expression of six of them (miR-100-5p, miR-29a-3p, miR-130a-3p, miR-10a-5p, miR-10b-5p, miR-203a), and determined that their levels were dramatically changed by at least 50-fold at different time points of the experiment (p < 0.01). The expression levels of five of these miRNAs (miR-100-5p, miR-10a-5p, miR-10b-5p, miR-130a-3p, and miR-29a-3p) started to increase from the fourth hour and continued to increase until the 48th hour in MDA-MB-435 cells compared to MCF-7 cells (p < 0.01). Simultaneously, the expression of one of these miRNAs (miR-203a) decreased from the sixth hour to the 48th hour in MDA-MB-435 as compared to MCF-7. We determined pathways associated with target genes using mirPath - DIANA TOOLS. Small RNAs including miRNA are essential regulatory molecules for gene expressions. In the literature, gene expressions have been published as burst and pulse in the form of discontinuous transcription. The data of the research suggested that time-dependent changes of miRNA expressions can be affected target gene transcriptional fluctuations in breast cancer cell and can be base for the further studies.

Roles of the HOX Proteins in Cancer Invasion and Metastasis

Invasion and metastasis correspond to the foremost cause of cancer-related death, and the molecular networks behind these two processes are extremely complex and dependent on the intra- and extracellular conditions along with the prime of the premetastatic niche. Currently, several studies suggest an association between the levels of HOX genes expression and cancer cell invasion and metastasis, which favour the formation of novel tumour masses. The deregulation of HOX genes by HMGA2/TET1 signalling and the regulatory effect of noncoding RNAs generated by the HOX loci can also promote invasion and metastasis, interfering with the expression of HOX genes or other genes relevant to these processes. In this review, we present five molecular mechanisms of HOX deregulation by which the HOX clusters products may affect invasion and metastatic processes in solid tumours.

[Development of Novel Drug Delivery System Targeting Exosomal microRNA]

Recently, mRNAs and microRNAs (miRNAs) have been identified in exosomes, which can be taken up by neighboring or distant cells. These exosomal-miRNAs may regulate gene expression in recipient cells. miRNAs are a type of non-coding RNA that induce post-transcriptional gene silencing of their target genes and regulate a wide range of biological processes, including apoptosis, differentiation, metabolism, and cell proliferation. According to recent reports, aberrant expression of miRNAs is associated with most pathological disease processes, including carcinogenesis. Therefore circulating onco-miRs are considered as significant therapeutic targets for cancer therapy. However, there is no report to regulate the function of miRNAs in exosomes. In this study, we developed novel drug delivery system using anti-exosome antibody-oligonucleotide conjugates (ExomiR-Tracker) for functional inhibition of circulating miRNAs. The "ExomiR-Tracker" is the world's first innovative molecule that has targeting property for exosome-recipient cells and specifically delivers nucleic acid medicines to the target cells. We found that ExomiR-Tracker can bind to the surface of exosomes and that the complexes are introduced into exosome-recipient cells then inhibit the activity of miRNA. We showed that ExomiR-Tracker can accumulate in cancerous tumors after intravenous administration. Existing technologies have difficulties for introducing anti-miR into exosomes and extremely low possibility to deliver anti-miR to exosome-recipient cells after intravenous administration. However, we successfully developed useful inhibition technology against exosomal-miRNA.

MicroRNAs in breast cancer: New maestros defining the melody

MicroRNAs, short non-coding single-stranded RNAs, are important regulators and gatekeepers of the coding genes in the human genome. MicroRNAs are highly conserved among species and expressed in different tissues and cell types. They are involved in almost all the biological processes as apoptosis, proliferation, cell cycle arrest and differentiation. Playing all these roles, it is not surprising that the deregulation of the microRNA profile causes a number of diseases including cancer. Breast cancer, the most commonly diagnosed malignancy in women, accounts for the highest cancer-related deaths worldwide. Different microRNAs were shown to be up or down regulated in breast cancer. MicroRNAs can function as oncogenes or tumor suppressors according to their targets. In this review, the most common microRNAs implicated in breast cancer are fully illustrated with their targets. Besides, the review highlights the effect of exosomal microRNA on breast cancer and the effect of microRNAs on drug and therapies resistance as well as the miRNA-based therapeutic strategies used until today.

Dual MicroRNA-Triggered Drug Release System for Combined Chemotherapy and Gene Therapy with Logic Operation

Combination therapy via stimulus-responsive drug release is known to improve treatment efficacy and minimize side effects. However, the use of low-abundance cancer biomarkers as molecular triggers to induce efficient drug release for combination therapy still remains a challenge. Herein, we developed a dual microRNA-responsive drug nanocarrier for catalytic release of doxorubicin (Dox) and small interfering RNA (siRNA) in cancerous cells for combined chemotherapy and gene therapy with logic operation. The nanocarrier is constructed by assembling two duplexes of DNA/RNA and Dox molecules onto DNA-functionalized gold nanoparticles. Two microRNA molecules (miRNA-21 and miRNA-10b overexpressed in MDA-MB-231) could alternatively catalyze the disassembly of the nanocarrier through a thermodynamically driven entropy gain process, during which Dox molecules are released, and the two pairs of released DNA/RNA duplex hybridize to generate siRNA (siBcl-2) in situ by strand displacement reactions. Quantum dots are used to track the process in living cells. The AND logic gate-based drug release system allows effective treatment of specific cancer cell types according to miRNA expression patterns. This strategy represents an effective means to overcome multidrug resistance and improve therapeutic effects.

Development of MicroRNAs as Potential Therapeutics against Cancer

MicroRNAs (miRNAs) are small noncoding RNAs that function at the posttranscriptional level in the cellular regulation process. miRNA expression exerts vital effects on cell growth such as cell proliferation and survival. In cancers, miRNAs have been shown to initiate carcinogenesis, where overexpression of oncogenic miRNAs (oncomiRs) or reduced expression of tumor suppressor miRNAs has been reported. In this review, we discuss the involvement of miRNAs in tumorigenesis, the role of synthetic miRNAs as either mimics or antagomirs to overcome cancer growth, miRNA delivery, and approaches to enhance their therapeutic potentials.

Delivery of dual miRNA through CD44-targeted mesoporous silica nanoparticles for enhanced and effective triple-negative breast cancer therapy

The development of new therapeutic strategies to target triple-negative breast cancer (TNBC) is in much demand to overcome the roadblocks associated with the existing treatment procedures. In this regard, therapies targeting the CD44 receptor have drawn attention for more than a decade. MicroRNAs (miRNAs) modulate post-transcriptional gene regulation and thus, the correction of specific miRNA alterations using miRNA mimics or antagomiRs is an emerging strategy to normalize the genetic regulation in the tumor microenvironment. It has been acknowledged that miR-34a is downregulated and miR-10b is upregulated in TNBC, which promotes tumorigenesis and metastatic dissemination. However, there are a few barriers related to miRNA delivery. Herein, we have introduced tailored mesoporous silica nanoparticles (MSNs) for the co-delivery of miR-34a-mimic and antisense-miR-10b. MSN was functionalized with a cationic basic side chain and then loaded with the dual combination to overexpress miR-34a and downregulate miR-10b simultaneously. Finally, the loaded MSNs were coated with an hyaluronic acid-appended PEG-PLGA polymer for specific targeting. The cellular uptake, release profile, and subsequent effect in TNBC cells were evaluated. In vitro and in vivo studies demonstrated high specificity in TNBC tumor targeting, leading to efficient tumor growth inhibition as well as the retardation of metastasis, which affirmed the clinical application potential of the system.

microRNAs in the Antitumor Immune Response and in Bone Metastasis of Breast Cancer: From Biological Mechanisms to Therapeutics

Breast cancer is the most common type of cancer in women, and the occurrence of metastasis drastically worsens the prognosis and reduces overall survival. Understanding the biological mechanisms that regulate the transformation of malignant cells, the consequent metastatic transformation, and the immune surveillance in the tumor progression would contribute to the development of more effective and targeted treatments. In this context, microRNAs (miRNAs) have proven to be key regulators of the tumor-immune cells crosstalk for the hijack of the immunosurveillance to promote tumor cells immune escape and cancer progression, as well as modulators of the metastasis formation process, ranging from the preparation of the metastatic site to the transformation into the migrating phenotype of tumor cells. In particular, their deregulated expression has been linked to the aberrant expression of oncogenes and tumor suppressor genes to promote tumorigenesis. This review aims at summarizing the role and functions of miRNAs involved in antitumor immune response and in the metastasis formation process in breast cancer. Additionally, miRNAs are promising targets for gene therapy as their modulation has the potential to support or inhibit specific mechanisms to negatively affect tumorigenesis. With this perspective, the most recent strategies developed for miRNA-based therapeutics are illustrated.

Applications of Two-Dimensional Nanomaterials in Breast Cancer Theranostics

Breast cancer is the leading cause of cancer-related mortality among women. Early stage diagnosis and treatment of this cancer are crucial to patients' survival. In addition, it is important to avoid severe side effects during the process of conventional treatments (surgery, chemotherapy, hormonal therapy, and targeted therapy) and increase the patients' quality of life. Over the past decade, nanomaterials of all kinds have shown excellent prospects in different aspects of oncology. Among them, two-dimensional (2D) nanomaterials are unique due to their physical and chemical properties. The functional variability of 2D nanomaterials stems from their large specific surface area as well as the diversity of composition, electronic configurations, interlayer forces, surface functionalities, and charges. In this review, the current status of 2D nanomaterials in breast cancer diagnosis and therapy is reviewed. In this respect, sensing of the tumor biomarkers, imaging, therapy, and theranostics are discussed. The ever-growing 2D nanomaterials are building blocks for the development of a myriad of nanotheranostics. Accordingly, there is the possibility to explore yet novel properties, biological effects, and oncological applications.

miRNAs as radio-response biomarkers for breast cancer stem cells

In breast cancer (BC), the presence of cancer stem cells (CSCs) has been related to relapse, metastasis, and radioresistance. Radiotherapy (RT) is an extended BC treatment, but is not always effective. CSCs have several mechanisms of radioresistance in place, and some miRNAs are involved in the cellular response to ionizing radiation (IR). Here, we studied how IR affects the expression of miRNAs related to stemness in different molecular BC subtypes. Exposition of BC cells to radiation doses of 2, 4, or 6 Gy affected their phenotype, functional characteristics, pluripotency gene expression, and in vivo tumorigenic capacity. This held true for various molecular subtypes of BC cells (classified by ER, PR and HER‐2 status), and for BC cells either plated in monolayer, or being in suspension as mammospheres. However, the effect of IR on the expression of eight stemness‐ and radioresistance‐related miRNAs (miR‐210, miR‐10b, miR‐182, miR‐142, miR‐221, miR‐21, miR‐93, miR‐15b) varied, depending on cell line subpopulation and clinicopathological features of BC patients. Therefore, clinicopathological features and, potentially also, chemotherapy regimen should be both taken into consideration, for determining a potential miRNA signature by liquid biopsy in BC patients treated with RT. Personalized and precision RT dosage regimes could improve the prognosis, treatment, and survival of BC patients.

The distinct transcriptomes of fast-twitch and slow-twitch muscles in Mongolian horses

Skeletal muscle is the largest organ system in the mammalian body and plays a key role in locomotion of horses. Fast and slow muscle fibers have different abilities and functions to adapt to exercises. To investigate the RNA and miRNA expression profiles in the muscles with different muscle fiber compositions on Mongolian horses. We examined the muscle fiber type population and produced deep RNA sequencing for different parts of skeletal muscles. And chose two of them with the highest difference in fast and slow muscle fiber population (splenius and gluteus medius) for comparing the gene expression profile of slow and fast muscle fiber types. We identified a total of 275 differentially expressed genes (DEGs), and 11 differentially expressed miRNAs (DEmiRs). In addition, target gene prediction and alternative splicing analysis were also performed. Significant correlations were found between the differentially expressed gene, miRNAs, and alternative splicing events. The result indicated that differentially expressed muscle-specific genes and target genes of miRNAs might co-regulating the performance of slow and fast muscle fiber types in Mongolian horses.

MicroRNAs and metastasis: small RNAs play big roles

MicroRNAs (miRNAs) are small non-coding RNAs regulating post-transcriptional gene expression. They play important roles in many biological processes under physiological or pathological conditions, including development, metabolism, tumorigenesis, metastasis, and immune response. Over the past 15 years, significant insights have been gained into the roles of miRNAs in cancer. Depending on the cancer type, miRNAs can act as oncogenes, tumor suppressors, or metastasis regulators. In this review, we focus on the role of miRNAs as components of molecular networks regulating metastasis. These miRNAs, termed metastamiRs, promote or inhibit metastasis through various mechanisms, including regulation of migration, invasion, colonization, cancer stem cell properties, epithelial-mesenchymal transition, and microenvironment. Some of these metastamiRs represent attractive therapeutic targets for cancer treatment.

mRNA and miRNA expression profiling of follicular variant of papillary thyroid carcinoma with and without distant metastases

Follicular Variant of Papillary Thyroid Carcinoma (FVPTC) is usually associated with a good outcome. Nevertheless, in rare cases, it develops distant metastases (1-9%). Our goal was to investigate whether mRNA and miRNA expression profiles may help distinguish between metastatic versus non-metastatic FVPTCs. Twenty-four primary FVPTCs, 12 metastatic and 12 non-metastatic, with similar clinicopathological features were selected and analyzed by nanoString nCounter technology using two distinct panels for expression analysis of 740 mRNA and 798 miRNAs. Data analysis was performed using the nanoString nSolver 3.0 software. Forty-seven mRNA and 35 miRNAs were differentially expressed between the two groups. Using these mRNA and miRNAs, metastatic and non-metastatic FVPTCs were clearly divided into two distinct clusters. Our results indicate that FVPTCs with metastatic abilities have different expression profiles compared to the non-metastatic. A prospective validation is needed to evaluate the usefulness of this molecular approach in the early identification of high-risk FVPTCs.

MicroRNA replacement therapy in cancer

Despite the recent progress in cancer management approaches, the mortality rate of cancer is still growing and there are lots of challenges in the clinics in terms of novel therapeutics. MicroRNAs (miRNA) are regulatory small noncoding RNAs and are already confirmed to have a great role in regulating gene expression level by targeting multiple molecules that affect cell physiology and disease development. Recently, miRNAs have been introduced as promising therapeutic targets for cancer treatment. Regulatory potential of tumor suppressor miRNAs, which enables regulation of entire signaling networks within the cells, makes them an interesting option for developing cancer therapeutics. In this regard, over recent decades, scientists have aimed at developing powerful and safe targeting approaches to restore these suppressive miRNAs in cancerous cells. The present review summarizes the function of miRNAs in tumor development and presents recent findings on how miRNAs have served as therapeutic agents against cancer, with a special focus on tumor suppressor miRNAs (mimics). Moreover, the latest investigations on the therapeutic strategies of miRNA delivery have been presented.

Competing endogenous RNA (ceRNA) cross talk and language in ceRNA regulatory networks: A new look at hallmarks of breast cancer

Breast cancer (BC) is the most frequently occurring malignancy in women worldwide. Despite the substantial advancement in understanding the molecular mechanisms and management of BC, it remains the leading cause of cancer death in women. One of the main reasons for this obstacle is that we have not been able to find the Achilles heel for the BC as a highly heterogeneous disease. Accumulating evidence has revealed that noncoding RNAs (ncRNAs), play key roles in the development of BC; however, the involving of complex regulatory interactions between the different varieties of ncRNAs in the development of this cancer has been poorly understood. In the recent years, the newly discovered mechanism in the RNA world is "competing endogenous RNA (ceRNA)" which proposes regulatory dialogues between different RNAs, including long ncRNAs (lncRNAs), microRNAs (miRNAs), transcribed pseudogenes, and circular RNAs (circRNAs). In the latest BC research, various studies have revealed that dysregulation of several ceRNA networks (ceRNETs) between these ncRNAs has fundamental roles in establishing the hallmarks of BC development. And it is thought that such a discovery could open a new window for a better understanding of the hidden aspects of breast tumors. Besides, it probably can provide new biomarkers and potential efficient therapeutic targets for BC. This review will discuss the existing body of knowledge regarding the key functions of ceRNETs and then highlights the emerging roles of some recently discovered ceRNETs in several hallmarks of BC. Moreover, we propose for the first time the "ceRnome" as a new term in the present article for RNA research.

MicroRNAs and breast cancer stem cells: Potential role in breast cancer therapy

MicroRNAs (miRNAs) can control cancer and cancer stem cells (CSCs), and this topic has drawn immense attention recently. Stem cells are a tiny population of a bulk of tumor cells that have enormous potential in expansion and metastasis of the tumor. miRNA have a crucial role in the management of the function of stem cells. This role is to either promote or suppress the tumor. In this review, we investigated the function and different characteristics of CSCs and function of the miRNAs that are related to them. We also demonstrated the role and efficacy of these miRNAs in breast cancer and breast cancer stem cells (BCSC). Eventually, we revealed the metastasis, tumor formation, and their role in the apoptosis process. Also, the therapeutic potential of miRNA as an effective method for the treatment of BCSC was described. Extensive research is required to investigate the employment or suppression of these miRNAs for therapeutics approached in different cancers in the future.

Role of miRNAs in hypoxia-related disorders

Hypoxia is a complex pathophysiological condition. The physiological and molecular responses to this stress have been extensively studied. However, the management of its ill effects still poses a challenge to clinicians. MicroRNAs (miRNAs) are short non-coding RNA molecules that control post-transcriptional gene expression. The regulatory role of miRNAs in hypoxic environments has been studied in many hypoxia-related disorders, however a comprehensive compilation and analysis of all data and the significance of miRNAs in hypoxia adaption is still lacking. This review summarizes the miRNAs related to various hypoxia-related disorders and highlights the computational approaches to study them. This would help in designing novel strategies toward efficient management of hypoxia-related disorders.

The fundamental role of miR-10b in metastatic cancer

Small, non-coding strands of RNA have been identified as a significant player in the pathology of cancer. One of the first miRNAs to be shown as having aberrant expression in cancer was miR-10b. Since the inaugural study on miR-10b, its role as a metastasis promoting factor has been extensively validated. To date, more than 100 studies have been completed on miR-10b and metastasis across 18 cancer types. This immense set of information holds possibilities for novel methods to improve the lives of many. This review outlines what is currently understood of miR-10b's clinical significance, its molecular regulation, and the possible diagnostic and therapeutic methods leveraging miR-10b as a fundamental target in metastatic cancer. Such methods would move us closer to developing a truly individualized therapeutic strategy against cancer and will likely provide unique information about cancer staging, disease outcome, metastatic potential, and ultimately survival.

OncomiR-10b hijacks the small molecule inhibitor linifanib in human cancers

The pervasive role of microRNAs (miRNAs) in cancer pathobiology drives the introduction of new drug development approaches such as miRNA inhibition. In order to advance miRNA-therapeutics, meticulous screening strategies addressing specific tumor targets are needed. Small molecule inhibitors represent an attractive goal for these strategies. In this study, we devised a strategy to screen for small molecule inhibitors that specifically inhibit, directly or indirectly, miR-10b (SMIRs) which is overexpressed in metastatic tumors. We found that the multi-tyrosine kinase inhibitor linifanib could significantly inhibit miR-10b and reverse its oncogenic function in breast cancer and liver cancer both in vitro and in vivo. In addition, we showed that the efficacy of linifanib to inhibit tyrosine kinases was reduced by high miR-10b levels. When the level of miR-10b is high, it can “hijack” the linifanib and reduce its kinase inhibitory effects in cancer resulting in reduced anti-tumor efficacy. In conclusion, our study describes an effective strategy to screen for small molecule inhibitors of miRNAs. We further propose that miR-10b expression levels, due to the newly described “hijacking” effect, may be used as a biomarker to select patients for linifanib treatment.