The miR-15a-miR-16-1 cluster controls prostate cancer by targeting multiple oncogenic activities

EVALUATION OF BCL2 AND ITS REGULATORY MIRS, MIR-15-B AND MIR-16 EXPRESSION CHANGES UNDER THE EXPOSURE OF EXTREMELY LOW-FREQUENCY ELECTROMAGNETIC FIELDS ON HUMAN GASTRIC CANCER CELL LINE

In this research, changes in the expression of B-cell lymphoma 2 (BCL2), miR-15-b and miR-16 in human adenocarcinoma gastric cancer cell line (AGS) following the exposure to magnetic flux densities (MFDs) of 0.2 and 2 mT continuously and discontinuously (1.5 h on/1.5 h off) for 18 h were investigated. Changes in the cell viability were evaluated by the MTT assay. Real-time PCR was used to evaluate the expression changes of BCL2, miR-15-b and miR-16. The results showed that extremely low frequency electromagnetic field (ELF-EMF) could significantly reduce the viability of AGS cells in the continuous MFD of 2 mT. The BCL2 expression was significantly decreased following the exposure to continuous MFDs of 0.2 and 2 mT and discontinuous MFD of 2 mT. The expressions of miR-15-b and miR-16 were significantly increased in continuous and discontinuous MFD of 2 mT. According to the results, weak and moderate extremely low-frequency electromagnetic fields can change the expressions of BCL2, miR-15-b and miR-16.

miRNA-148b and its role in various cancers

miRNA-148b belongs to the family miR-148/-152, with significant differences in nonseed sequences, which can target diverse mRNA molecules. Reportedly, it may undergo deregulation in lung and ovarian cancers and downregulation in gastric, pancreatic and colon cancers. However, there is a need for further studies to better characterize its mechanism of action and in different types of cancer. In this review, we focus on the aberrant expression of miR-148b in different cancer types and highlight its main target genes and signaling pathways, as well as its pathophysiologic role and relevance to tumorigenesis in several types of cancer.

TCF7L1 regulates cytokine response and neuroendocrine differentiation of prostate cancer

Neuroendocrine differentiation (NED) is associated with WNT signaling activation and can be significantly observed after failure of androgen-deprivation therapy (ADT) for prostatic adenocarcinomas. Cytokine signaling is stimulated in NED prostate cancer; however, how ADT-upregulated WNT signaling promotes activation of cytokine signaling and contributes to NED of prostate cancer is poorly understood. In this study, we identified ADT-mediated upregulation of transcription factor 7 like 1 (TCF7L1), which increases the cytokine response and enhances NED of prostate cancer through interleukin (IL)-8/C-X-C motif chemokine receptor type 2 (CXCR2) signaling activation. ADT induced the secretion of WNT4 which upon engagement of TCF7L1 in prostate cancer cells, enhanced IL-8 and CXCR2 expressions. TCF7L1 directly binds to the regulatory sequence region of IL-8 and CXCR2 through WNT4 activation, thus upregulating IL-8/CXCR2 signaling-driven NED and cell motility. Analysis of prostate tissue samples collected from small-cell neuroendocrine prostate cancer (SCPC) and castration-resistant prostate cancer (CRPC) tumors showed an increased intensity of nuclear TCF7L1 associated with CXCR2. Our results suggest that induction of WNT4/TCF7L1 results in increased NED and malignancy in prostate cancer that is linked to dysregulation of androgen receptor signaling and activation of the IL-8/CXCR2 pathway.

What Do We Have to Know about PD-L1 Expression in Prostate Cancer? A Systematic Literature Review. Part 5: Epigenetic Regulation of PD-L1

Epigenetic alterations (including DNA methylation or miRNAs) influence oncogene/oncosuppressor gene expression without changing the DNA sequence. Prostate cancer (PC) displays a complex genetic and epigenetic regulation of cell-growth pathways and tumor progression. We performed a systematic literature review (following PRISMA guidelines) focused on the epigenetic regulation of PD-L1 expression in PC. In PC cell lines, CpG island methylation of the CD274 promoter negatively regulated PD-L1 expression. Histone modifiers also influence the PD-L1 transcription rate: the deletion or silencing of the histone modifiers MLL3/MML1 can positively regulate PD-L1 expression. Epigenetic drugs (EDs) may be promising in reprogramming tumor cells, reversing epigenetic modifications, and cancer immune evasion. EDs promoting a chromatin-inactive transcriptional state (such as bromodomain or p300/CBP inhibitors) downregulated PD-L1, while EDs favoring a chromatin-active state (i.e., histone deacetylase inhibitors) increased PD-L1 expression. miRNAs can regulate PD-L1 at a post-transcriptional level. miR-195/miR-16 were negatively associated with PD-L1 expression and positively correlated to longer biochemical recurrence-free survival; they also enhanced the radiotherapy efficacy in PC cell lines. miR-197 and miR-200a-c positively correlated to PD-L1 mRNA levels and inversely correlated to the methylation of PD-L1 promoter in a large series. miR-570, miR-34a and miR-513 may also be involved in epigenetic regulation.

MicroRNAs Role in Breast Cancer: Theranostic Application in Saudi Arabia

Breast cancer is an aggressive silent disease, representing 11.7% of the diagnosed cancer worldwide, and it is also a leading cause of death in Saudi Arabia. Consequently, microRNAs have emerged recently as potential biomarkers to diagnose and monitor such cases at the molecular level, which tends to be problematic during diagnosis. MicroRNAs are highly conserved non- coding oligonucleotide RNA. Over the last two decades, studies have determined the functional significance of these small RNAs and their impact on cellular development and the interaction between microRNAs and messenger RNAs, which affect numerous molecular pathways and physiological functions. Moreover, many disorders, including breast cancer, are associated with the dysregulation of microRNA. Sparingly, many microRNAs can suppress cancer cell proliferation, apoptosis, angiogenesis, invasion, metastasis, and vice versa. Remarkably, microRNAs can be harvested from patients’ biofluids to predict disease progression that considered a non-invasive method. Nevertheless, MicroRNAs are currently utilized as anti- cancer therapies combined with other drug therapies or even as a single agents’ treatment. Therefore, this review will focus on microRNAs’ role in breast cancer as an indicator of disease progression. In addition, this review summarizes the current knowledge of drug sensitivity and methods in detecting microRNA and their application to improve patient care and identifies the current gaps in this field.

microRNA-based diagnostic and therapeutic applications in cancer medicine

It has been almost two decades since the first link between microRNAs and cancer was established. In the ensuing years, this abundant class of short noncoding regulatory RNAs has been studied in virtually all cancer types. This tremendously large body of research has generated innovative technological advances for detection of microRNAs in tissue and bodily fluids, identified the diagnostic, prognostic, and/or predictive value of individual microRNAs or microRNA signatures as potential biomarkers for patient management, shed light on regulatory mechanisms of RNA-RNA interactions that modulate gene expression, uncovered cell-autonomous and cell-to-cell communication roles of specific microRNAs, and developed a battery of viral and nonviral delivery approaches for therapeutic intervention. Despite these intense and prolific research efforts in preclinical and clinical settings, there are a limited number of microRNA-based applications that have been incorporated into clinical practice. We review recent literature and ongoing clinical trials that highlight most promising approaches and standing challenges to translate these findings into viable microRNA-based clinical tools for cancer medicine. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Nucleic acid delivery for therapeutic applications

Recent medical advances have exploited the ability to address a given disease at the underlying level of transcription and translation. These treatment paradigms utilize nucleic acids - including short interfering RNA (siRNA), microRNA (miRNA), antisense oligonucleotides (ASO), and messenger RNA (mRNA) - to achieve a desired outcome ranging from gene knockdown to induced expression of a selected target protein. Towards this end, numerous strategies for encapsulation or stabilization of various nucleic acid structures have been developed in order to achieve intracellular delivery. In this review, we discuss several therapeutic applications of nucleic acids directed towards specific diseases and tissues of interest, in particular highlighting recent technologies which have reached late-stage clinical trials and received FDA approval.

miR-28-3p inhibits prostate cancer cell proliferation, migration and invasion, and promotes apoptosis by targeting ARF6

Previous studies have reported that the expression levels of microRNA (miR)-28-3p are downregulated in prostate cancer (PCa) compared with those in adjacent normal tissues. However, to the best of our knowledge, the function and underlying mechanisms of miR-28-3p in PCa have not been reported. The present study aimed to explore the role of miR-28-3p and its mechanism in the development of PCa. In the present study, miR-28-3p and ADP-ribosylation factor 6 (ARF6) expression levels were analyzed using reverse transcription-quantitative PCR (RT-qPCR). Cell proliferation, colony formation, apoptosis, migration and invasion were determined using Cell Counting Kit-8, colony forming, flow cytometry and Transwell assays, respectively. The association between miR-28-3p and ARF6 was investigated using a dual luciferase reporter assay. ARF6, Rac1, Erk1/2 and phosphorylated (p)-Erk1/2 protein expression levels were analyzed using western blotting. The results of the present study revealed that miR-28-3p expression levels were downregulated, whereas ARF6 expression levels were upregulated in PCa cell lines (LNCaP, 22Rv-1, PC-3 and DU145) compared with those in the normal prostate line RWPE-1. The overexpression of miR-28-3p promoted cell apoptosis, and inhibited cell proliferation, colony formation, migration and invasion. However, the knockdown of miR-28-3p exerted the opposite results. The results of the dual luciferase reporter assays, RT-qPCR and western blotting indicated that ARF6 was a target gene of miR-28-3p. Finally, rescue experiments demonstrated that ARF6 overexpression attenuated the effects of the miR-28-3p mimic by upregulating Rac1 and p-Erk1/2 expression in PCa cells. In conclusion, these findings indicated that miR-28-3p may inhibit the biological behaviors of PCa cells by targeting ARF6, and therefore may represent a novel therapeutic candidate for PCa.

Learning noncoding RNA biology from viruses

Insights into interactions between viral factors and the cellular machinery usually lead to discoveries concerning host cell biology. Thus, the gene expression field has historically relied on viral model systems to discover mechanisms underlying different cellular processes. In recent years, the functional characterization of the small nuclear noncoding RNAs expressed by the oncogenic Herpesvirus saimiri, called HSURs, resulted in the discovery of two mechanisms for the regulation of gene expression. HSUR1 and HSUR2 associate with host microRNAs, which are small noncoding RNAs that broadly regulate gene expression by binding to messenger RNAs. HSUR1 provided the first example of a process known as target-directed miRNA degradation that operates in cells to regulate miRNA populations. HSUR2 functions as a miRNA adaptor, uncovering an entirely new, indirect mechanism by which miRNAs can inhibit mRNA function. Here, I review the path that led to these discoveries and their implications and postulate new exciting questions about the functions of these fascinating viral noncoding RNAs.

Role of Metastasis-Related microRNAs in Prostate Cancer Progression and Treatment

Simple Summary

In this review article we summarize the current literature on the pro- and anti-metastatic roles of distinct microRNAs in prostate cancer with a particular focus on their impact on invasion, migration and epithelial-to-mesenchymal transition. Moreover, we give a brief overview on how this knowledge developed so far into novel therapeutic approaches to target metastatic prostate cancer.

Abstract

Prostate cancer (PCa) is one of the most prevalent cancer types in males and the consequences of its distant metastatic deposits are the leading cause of PCa mortality. Therefore, identifying the causes and molecular mechanisms of hematogenous metastasis formation is of considerable clinical importance for the future development of improved therapeutic approaches. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the post-transcriptional level by targeting messenger RNAs. Numerous studies have identified miRNAs as promotors or inhibitors of metastasis and revealed, in part, their targeting pathways in PCa. Because miRNAs are remarkably stable and can be detected in both tissue and body fluid, its potential as specific biomarkers for metastasis and therapeutic response is also currently under preclinical evaluation. In the present review, we focus on miRNAs that are supposed to initiate or suppress metastasis by targeting several key mRNAs in PCa. Metastasis-suppressing miRNAs include miR-33a-5p, miR-34, miR-132 and miR-212, miR-145, the miR-200 family (incl. miR-141-3p), miR-204-5p, miR-532-3p, miR-335, miR-543, miR-505-3p, miR 19a 3p, miR-802, miR-940, and miR-3622a. Metastasis-promoting RNAs, such as miR-9, miR-181a, miR-210-3, miR-454, miR-671-5p, have been shown to increase the metastatic potential of PCa cells. Other metastasis-related miRNAs with conflicting reports in the literature are also discussed (miR-21 and miR-186). Finally, we summarize the recent developments of miRNA-based therapeutic approaches, as well as current limitations in PCa. Taken together, the metastasis-controlling miRNAs provide the potential to be integrated in the strategy of diagnosis, prognosis, and treatment of metastatic PCa. Nevertheless, there is still a lack of consistency between certain miRNA signatures and reproducibility, which impedes clinical implementation.

MicroRNA as an Important Target for Anticancer Drug Development

Cancer has become the second greatest cause of death worldwide. Although there are several different classes of anticancer drugs that are available in clinic, some tough issues like side-effects and low efficacy still need to dissolve. Therefore, there remains an urgent need to discover and develop more effective anticancer drugs. MicroRNAs (miRNAs) are a class of small endogenous non-coding RNAs that regulate gene expression by inhibiting mRNA translation or reducing the stability of mRNA. An abnormal miRNA expression profile was found to exist widely in cancer cell, which induces limitless replicative potential and evading apoptosis. MiRNAs function as oncogenes (oncomiRs) or tumor suppressors during tumor development and progression. It was shown that regulation of specific miRNA alterations using miRNA mimics or antagomirs can normalize the gene regulatory network and signaling pathways, and reverse the phenotypes in cancer cells. The miRNA hence provides an attractive target for anticancer drug development. In this review, we will summarize the latest publications on the role of miRNA in anticancer therapeutics and briefly describe the relationship between abnormal miRNAs and tumorigenesis. The potential of miRNA-based therapeutics for anticancer treatment has been critically discussed. And the current strategies in designing miRNA targeting therapeutics are described in detail. Finally, the current challenges and future perspectives of miRNA-based therapy are conferred.

Upregulation of miR181a/miR212 Improves Myogenic Commitment in Murine Fusion-Negative Rhabdomyosarcoma

Fusion-negative rhabdomyosarcoma (FN-RMS) is the most common soft tissue sarcoma of childhood arising from undifferentiated skeletal muscle cells from uncertain origin. Currently used therapies are poorly tumor-specific and fail to tackle the molecular machinery underlying the tumorigenicity and uncontrolled proliferation of FN-RMS. We and other groups recently found that microRNAs (miRNA) network contributes to myogenic epigenetic memory and can influence pluripotent stem cell commitments. Here, we used the previously identified promyogenic miRNAs and tailored it to the murine FN-RMS. Subsequently, we addressed the effects of miRNAs in vivo by performing syngeneic transplant of pre-treated FN-RMS cell line in C57Bl/6 mice. miRNA pre-treatment affects murine FN-RMS cell proliferation in vivo as showed by bioluminescence imaging analysis, resulting in better muscle performances as highlighted by treadmill exhaustion tests. In conclusion, in our study we identified a novel miRNA combination tackling the anti-myogenic features of FN-RMS by reducing proliferation and described novel antitumorigenic therapeutic targets that can be further explored for future pre-clinical applications.

MicroRNA-16-5p Aggravates Myocardial Infarction Injury by Targeting the Expression of Insulin Receptor Substrates 1 and Mediating Myocardial Apoptosis and Angiogenesis

PURPOSE

Myocardial infarction is a common cardiovascular disease. MicroRNA-16-5p (miR-16-5p) was upregulated in heart and kidney hypoxia/reoxygenation (H/R) injury. However, the role of miR-16-5p in myocardial infarction injury is still unclear.

METHODS

Human adult ventricular cardiomyocytes (AC16) were treated with ischemia/reperfusion (H/R). The miR-16-5p level was evaluated through real-time PCR. The activity of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) was detected via LDH and CK-MB monitoring kits. Cell viability was examined with 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetra-zolium bromide (MTT) assay. Western blotting was used to analyze the protein levels. The luci-ferase report assay confirmed the relative luciferase activity.

RESULTS

miR-16-5p was elevated in H/R-treated AC16 cells. miR-16-5p overexpression and knockdown were carried out. miR-16-5p knockdown repressed cell apoptosis, attenuated LDH and CK-MB activities, and enhanced cell viability in H/R-treated AC16 cells. Moreover, miR-16-5p knockdown promoted angiogenesis in human microvascular endothelial cells (HMVEC), causing elevation of vascular endothelial growth factor (VEGF), insulin receptor substrates 1 (IRS1), minichromosome maintenance complex component 2 (MCM2) and proliferating cell nuclear antigen (PCNA) protein levels. Moreover, miR-16-5p was testified to target IRS1. IRS1 silencing alleviated miR-16-5p knockdown-mediated inhibition of apoptosis in AC16 cells.

CONCLUSION

miR-16-5p knockdown increased cell viability and angiogenesis, as well as inhibited cell apoptosis by increasing IRS1. These findings indicated that miR-16-5p knockdown may be a new therapeutic target for myocardial infarction.

Immunomodulation by Bifidobacterium animalis subsp. lactis Bb12: Integrative Analysis of miRNA Expression and TLR2 Pathway-Related Target Proteins in Swine Monocytes

Bifidobacterium animalis subsp. lactis Bb12 is a widely used probiotic that provides numerous health benefits to its host, many due to its immunomodulatory properties. Although the precise mechanism of modulation is still under investigation, several reports associate the interaction of TLR2 with components of the bacterial cell wall inducing a signaling cascade that culminates with the production of cytokines and co-stimulatory molecules. MicroRNAs (miRNAs) have emerged as important post-transcriptional regulators of immune responses, including those toward probiotics. In this study, we analyzed the miRNA expression profile in swine monocytes exposed to Bb12 by using an anti-TLR2 blocking strategy and Bb12 involvement in the regulation of the TLR2 pathway. As a result, the expression of 40 miRNAs was influenced by the treatments (p < 0.01), and 15 differentially expressed miRNAs with validated miRNA–mRNA interactions with around 26 proteins related to the TLR2 pathway were identified. The miRNAs upregulated in response to Bb12 included miR-15a-5p, miR-16-5p, miR-26a-5p, miR-29b-3p, and miR-30d-5p, and the following showed downregulation: miR-181a-5p, miR-19b-3p, miR-21-5p, miR-23a-5p, and miR-221-3p. The expression of let-7c-5p, let-7f-5p, miR-146b-5p, miR-150-5p, and miR-155-5p was increased by Bb12 only when TLR2 was blocked. The identified miRNA common targets were downstream proteins from bacterial recognition via TLR2, such as MyD88, TRAF6, and MAPK members; transcription factors such as NF-κB and AP-1; and cytokines such as IL-6, IL-10, and TNF-α. TLR2 participation was abrogated by anti-TLR2 antibody and suggests that bacterial recognition is complemented by other receptors since there were still changes in the microtranscriptome.

Mastiha has efficacy in immune-mediated inflammatory diseases through a microRNA-155 Th17 dependent action

Mastiha is a natural nutritional supplement with known anti-inflammatory properties. Non-alcoholic fatty liver disease (NAFLD) and Inflammatory bowel disease (IBD) are immune mediated inflammatory diseases that share common pathophysiological features. Mastiha has shown beneficial effects in both diseases. MicroRNAs have emerged as key regulators of inflammation and their modulation by phytochemicals have been extensively studied over the last years. Therefore, the aim of this study was to investigate whether a common route exists in the anti-inflammatory activity of Mastiha, specifically through the regulation of miRNA levels. Plasma miR-16, miR-21 and miR-155 were measured by Real-Time PCR before and after two double blinded and placebo-controlled randomized clinical trials with Mastiha. In IBD and particularly in ulcerative colitis patients in relapse, miR-155 increased in the placebo group (p = 0.054) whereas this increase was prevented by Mastiha. The mean changes were different in the two groups even after adjusting for age, sex and BMI (p = 0.024 for IBD and p = 0.042). Although the results were not so prominent in NAFLD, miR-155 displayed a downward trend in the placebo group (p = 0.054) whereas the levels did not changed significantly in the Mastiha group in patients with less advanced fibrosis. Our results propose a regulatory role for Mastiha in circulating levels of miR-155, a critical player in T helper-17 (Th17) differentiation and function.

Potential clinical use of miRNA molecules in the diagnosis of prostate cancer

Prostate cancer (PCa) is the most common type of cancer among men in Europe and this applies to almost the whole world. Current recommendations for screening and diagnosis are based on prostate specific antigen (PSA) measurements and the digital rectal examination (DRE). Both of them trigger the prostate biopsy. Limited specificity of the PSA test brings, however, a need to develop new and better diagnostic tools. In the last few years, new approaches for providing significantly better biomarkers, an alternative to PSA, have been introduced. Modern biomarkers show improvement not only as a diagnostic procedure, but also for staging, evaluating aggressiveness and managing the therapeutic process. The most promising group are molecular markers; among them microRNAs (miRNAs, miRs) are most frequent. miRNAs represent a class of about 22 nucleotides long, small non-coding RNAs, which are involved in gene expression regulation at the post-transcriptional level. This article reports a revision about the role of miRNAs in PCa including data of Adreno Receptor (AR) signaling, cell cycle, epithelial mesenchymal transition (EMT) process, cancer stem cells (CSCs) regulation and even the role of miRNAs as PCa therapeutic tool. Finding better PCa biomarkers, replacing the current PSA measurement, is firmly needed in modern oncology practice.

Epigenetic Deregulation of Apoptosis in Cancers

Cancer cells possess the ability to evade apoptosis. Genetic alterations through mutations in key genes of the apoptotic signaling pathway represent a major adaptive mechanism of apoptosis evasion. In parallel, epigenetic changes via aberrant modifications of DNA and histones to regulate the expression of pro- and antiapoptotic signal mediators represent a major complementary mechanism in apoptosis regulation and therapy response. Most epigenetic changes are governed by the activity of chromatin modifying enzymes that add, remove, or recognize different marks on histones and DNA. Here, we discuss how apoptosis signaling components are deregulated at epigenetic levels, particularly focusing on the roles of chromatin-modifying enzymes in this process. We also review the advances in cancer therapies with epigenetic drugs such as DNMT, HMT, HDAC, and BET inhibitors, as well as their effects on apoptosis modulation in cancer cells. Rewiring the epigenome by drug interventions can provide therapeutic advantage for various cancers by reverting therapy resistance and leading cancer cells to undergo apoptotic cell death.

Diagnostic and prognostic potential of the proteomic profiling of serum-derived extracellular vesicles in prostate cancer

Extracellular vesicles (EVs) and their cargo represent an intriguing source of cancer biomarkers for developing robust and sensitive molecular tests by liquid biopsy. Prostate cancer (PCa) is still one of the most frequent and deadly tumor in men and analysis of EVs from biological fluids of PCa patients has proven the feasibility and the unprecedented potential of such an approach. Here, we exploited an antibody-based proteomic technology, i.e. the Reverse-Phase Protein microArrays (RPPA), to measure key antigens and activated signaling in EVs isolated from sera of PCa patients. Notably, we found tumor-specific protein profiles associated with clinical settings as well as candidate markers for EV-based tumor diagnosis. Among others, PD-L1, ERG, Integrin-β5, Survivin, TGF-β, phosphorylated-TSC2 as well as partners of the MAP-kinase and mTOR pathways emerged as differentially expressed endpoints in tumor-derived EVs. In addition, the retrospective analysis of EVs from a 15-year follow-up cohort generated a protein signature with prognostic significance. Our results confirm that serum-derived EV cargo may be exploited to improve the current diagnostic procedures while providing potential prognostic and predictive information. The approach proposed here has been already applied to tumor entities other than PCa, thus proving its value in translational medicine and paving the way to innovative, clinically meaningful tools.

MicroRNAs as Epigenetic Determinants of Treatment Response and Potential Therapeutic Targets in Prostate Cancer

Prostate cancer (PCa) is the second most common tumor in men worldwide, and the fifth leading cause of male cancer-related deaths in western countries. PC is a very heterogeneous disease, meaning that optimal clinical management of individual patients is challenging. Depending on disease grade and stage, patients can be followed in active surveillance protocols or undergo surgery, radiotherapy, hormonal therapy, and chemotherapy. Although therapeutic advancements exist in both radiatiotherapy and chemotherapy, in a considerable proportion of patients, the treatment remains unsuccessful, mainly due to tumor poor responsiveness and/or recurrence and metastasis. microRNAs (miRNAs), small noncoding RNAs that epigenetically regulate gene expression, are essential actors in multiple tumor-related processes, including apoptosis, cell growth and proliferation, autophagy, epithelial-to-mesenchymal transition, invasion, and metastasis. Given that these processes are deeply involved in cell response to anti-cancer treatments, miRNAs have been considered as key determinants of tumor treatment response. In this review, we provide an overview on main PCa-related miRNAs and describe the biological mechanisms by which specific miRNAs concur to determine PCa response to radiation and drug therapy. Additionally, we illustrate whether miRNAs can be considered novel therapeutic targets or tools on the basis of the consequences of their expression modulation in PCa experimental models.

MicroRNAs Determining Carcinogenesis by Regulating Oncogenes and Tumor Suppressor Genes During Cell Cycle

AIM

To provide a review considering microRNAs regulating oncogenes and tumor suppressor genes during the different stages of cell cycle, controlling carcinogenesis.

METHODS

The role of microRNAs involved as oncogenes' and tumor suppressor genes' regulators in cancer was searched in the relevant available literature in MEDLINE, including terms such as "microRNA", "oncogenes", "tumor suppressor genes", "metastasis", "cancer" and others.

RESULTS

MicroRNAs determine the expression levels of multiple cell cycle regulators, such as cyclins, cyclin dependent kinases and other major cell cycle activators including retinoblastoma 1 (RB- 1) and p53, resulting in alteration and promotion/inhibition of the cell cycle.

CONCLUSION

MicroRNAs are proven to have a key role in cancer pathophysiology by altering the expression profile of different regulator proteins during cell division cycle and DNA replication. Thus, by acting as oncogenes and tumor suppressor genes, they can either promote or inhibit cancer development and formation, revealing their innovative role as biomarkers and therapeutic tools.

The roles of microRNAs in mouse development

Hundreds of microRNAs (miRNAs) are expressed in distinct spatial and temporal patterns during embryonic and postnatal mouse development. The loss of all miRNAs through the deletion of critical miRNA biogenesis factors results in early lethality. The function of each miRNA stems from their cumulative negative regulation of multiple mRNA targets expressed in a particular cell type. During development, miRNAs often coordinate the timing and direction of cell fate transitions. In adults, miRNAs frequently contribute to organismal fitness through homeostatic roles in physiology. Here, we review how the recent dissection of miRNA-knockout phenotypes in mice as well as advances related to their targets, dosage, and interactions have collectively informed our understanding of the roles of miRNAs in mammalian development and adaptive responses.

Interplay between MAPK/ERK signaling pathway and MicroRNAs: A crucial mechanism regulating cancer cell metabolism and tumor progression

Mitogen-activated protein kinase (MAPK) signal transduction, as a highly conserved signaling pathway, is reported to be involved in various biological events, including metabolic reprogramming, cell proliferation, survival, and differentiation. Mutations in key molecules involved in MAPK/ERK signaling and dysregulation of this pathway are very common events in various human malignancies, which make the MAPK signaling a crucial signaling pathway participating in the regulation of glucose uptake by malignant cells and tumorigenesis. MicroRNAs (miRNAs), as small non-coding RNAs, are critical regulators of gene expression that play key roles in cancer initiation and progression. On the other hand, these small RNAs mutually regulate the MAPK signaling which is often overexpressed in the case of cancer progression; suggesting that crosstalk between miRNAs and this signaling pathway plays a pivotal role in the development of human cancers. Some miRNAs such as miR-20b, miR-34c-3p, miR-152, miR-181a, and miR-302b through inhibiting MAPK signaling, and miR-193a-3p, miR-330-3p, and miR-592 by activating this signaling pathway, play imperative roles in tumorigenesis. Therefore, in this review, we aimed to focus on the interplay between miRNAs and MAPK signaling in the various steps of tumorigenesis, including metabolic regulation, cell proliferation, apoptosis, metastasis, angiogenesis, and drug resistance.

Androgen Receptor-Related Non-coding RNAs in Prostate Cancer

Prostate cancer (PCa) is the second leading cause of cancer-related death among men in the United States. Androgen receptor (AR) signaling is the dominant oncogenic pathway in PCa and the main strategy of PCa treatment is to control the AR activity. A large number of patients acquire resistance to Androgen deprivation therapy (ADT) due to AR aberrant activation, resulting in castration-resistant prostate cancer (CRPC). Understanding the molecular mechanisms underlying AR signaling in the PCa is critical to identify new therapeutic targets for PCa patients. The recent advances in high-throughput RNA sequencing (RNA-seq) techniques identified an increasing number of non-coding RNAs (ncRNAs) that play critical roles through various mechanisms in different diseases. Some ncRNAs have shown great potentials as biomarkers and therapeutic targets. Many ncRNAs have been investigated to regulate PCa through direct association with AR. In this review, we aim to comprehensively summarize recent findings of the functional roles and molecular mechanisms of AR-related ncRNAs as AR regulators or targets in the progression of PCa.

Histone Deacetylase Modifications by Probiotics in Colorectal Cancer

It has been demonstrated that epigenetic modifications of histone (acetylation/deacetylation) participate in a critical role in cancer progression by the regulation of gene expression. Several processes could be regulated by deacetylation of histone and non-histone proteins such as apoptosis, proliferation, cell metabolism, differentiation, and DNA repair. Hence, histone deacetylase inhibitors (HDACis) are employed as a hopeful group of anti-cancer drugs that could inhibit tumor cell proliferation or apoptosis. The elimination of the acetylation marks that take place as an essential epigenetic change in cancer cells is associated to HDAC expression and activity. In this regard, it has been reported that class I HDACs have a vital role in the regulation of tumor cell proliferation. OBJECTIVES: In this review, we discuss whether gut origin microorganisms could promote cancer or tumor resistance and explain mechanisms of these processes. CONCLUSIONS: According to the enormous capacity of the metabolism of the intestine microbiota, bacteria are likely to convert nutrients and digestive compounds into metabolites that regulate epigenetic in cancer. The effect of the food is of interest on epigenetic changes in the intestinal mucosa and colonocytes, as misleading nucleotide methylation may be a prognostic marker for colorectal cancer (CRC). Since epigenetic changes are potentially reversible, they can serve as therapeutic targets for preventing CRC. However, various mechanisms have been identified in the field of prevention, treatment, and progression of cancer by probiotics, which include intestinal microbiota modulation, increased intestinal barrier function, degradation of potential carcinogens, protective effect on intestinal epithelial damage, and increased immune function.

Epigenetic effects toward new insights as potential therapeutic target in B-thalassemia

Background

Fetal hemoglobin (HbF) induction has shown promise for the treatment of β-hemoglobinopathies. HbF induction in β-thalassemia could overcome ineffective hematopoiesis and thus terminate transfusion dependency for formerly transfusion dependant patients. Several miRNAs have been found to reactivate γ-globin expression and increase HbF. In this study, we aimed to investigate the expression of 4 miRNAs (miR-15a, miR-16-1, miR-96, and miR-486-3p) in high HbF thalassemia patients and correlate their levels with the patients’ HbF levels then, in order to predict the exact role of the studied miRNAs in hematopoiesis, a bioinformatic analysis was carried out. We went through this bioinformatic analysis to determine the network of genes regulated by miRNAs and further investigate the interaction between all of them through their involvement in hematopoiesis. In this study, the differential expression was measured by qRT-PCR for 40 patients with high HbF and compared to 20 healthy controls. Bioinformatics was conducted involving functional annotation and pathway enrichment analyses.

Results

The studied microRNAs were significantly deregulated in thalassemia patients in correlation with HbF. Functional annotation and pathway enrichment analyses revealed a major role of miR-486-3p and miR-15a in HbF induction.

Conclusion

MiR-486-3p and miR-15a are crucial for HbF induction. Further validating studies are needed.

Interferon regulatory factor 1 (IRF-1) downregulates Checkpoint kinase 1 (CHK1) through miR-195 to upregulate apoptosis and PD-L1 expression in Hepatocellular carcinoma (HCC) cells

BACKGROUND

CHK1 is considered an oncogene with overexpression in numerous cancers. However, CHK1 signalling regulation in hepatocellular carcinoma (HCC) remains unclear.

METHODS

CHEK1 mRNA, protein, pri-miR-195 and miR-195 expression in HCC tissue was determined by qPCR, WB and IF staining assay. Survival analyses in HCC with high- and low-CHEK1 mRNA expression was performed using TCGA database. Relative luciferase activity was investigated in HCC cells transfected with p-CHEK1 3'UTR. Apoptosis was detected by TUNEL assay. NK and CD8+ T cells were analysed by flow cytometry.

RESULTS

CHK1 is increased in human HCC tumours compared with non-cancerous liver. High CHK1 predicts worse prognosis. IFN-γ suppresses CHK1 via IRF-1 in HCC cells. The molecular mechanism of IRF-1 suppressing CHK1 is post-transcriptional by promoting miR-195 binding to CHEK1 mRNA 3'UTR, which exerts a translational blockade. Upregulated IRF-1 inhibits CHK1, which induces apoptosis of HCC cells. Likewise, CHK1 inhibition augments cellular apoptosis in HCC tumours. This effect may be a result of increased tumour NK cell infiltration. However, IRF-1 expression or CHK1 inhibition also upregulates PD-L1 expression via increased STAT3 phosphorylation.

CONCLUSIONS

IRF-1 induces miR-195 to suppress CHK1 protein expression. Both increased IRF-1 and decreased CHK1 upregulate cellular apoptosis and PD-L1 expression in HCC.

Small RNAs as biomarkers to differentiate benign and malign prostate diseases: An alternative for transrectal punch biopsy of the prostate?

Prostate cancer (PCa) is the most common cancer and the third most frequent cause of male cancer death in Germany. MicroRNAs (miRNA) appear to be involved in the development and progression of PCa. A diagnostic differentiation from benign prostate hyperplasia (BPH) is often only possible through transrectal punch biopsy. This procedure is described as painful and carries risks. It was investigated whether urinary miRNAs can be used as biomarkers to differentiate the prostate diseases above. Therefore urine samples from urological patients with BPH (25) or PCa (28) were analysed using Next-Generation Sequencing to detect the expression profile of total and exosomal miRNA/piRNA.

79 miRNAs and 5 piwi-interacting RNAs (piRNAs) were significantly differentially expressed (adjusted p-value < 0.05 and log2-Fc > 1 or < -1). Of these, 6 miRNAs and 2 piRNAs could be statistically validated (AUC on test cohort > = 0.7). In addition, machine-learning algorithms were used to identify a panel of 22 additional miRNAs, whose interaction makes it possible to differentiate the groups as well. There are promising individual candidates for potential use as biomarkers in prostate cancer. The innovative approach of applying machine learning methods to this kind of data could lead to further small RNAs coming into scientific focus, which have so far been neglected.

MiRNAs and radical prostatectomy: Current data, bioinformatic analysis and utility as predictors of tumour relapse

BACKGROUND

Studies of microRNAs (miRNAs) and genes have particular interest for cancer biology and medicine due to the discovery of new therapeutic targets and markers. These studies are extensively influenced by anticancer therapy, as miRNAs interfere with the therapy's efficacy in prostate cancer (PCa).

OBJECTIVES

In this article, we summarise the available data on the influence of radical prostatectomy (RP) and biochemical recurrence on miRNA expression.

MATERIALS AND METHODS

Molecular targets of these miRNAs, as well as the reciprocal relations between different miRNAs and their targets, were studied using the DIANA, STRING and TransmiR databases. Special attention was dedicated to the mechanisms of PCa development, miRNA, and associated genes as tumour development mediators.

RESULTS AND DISCUSSION

Combined analysis of the databases and available literature indicates that expression of four miRNAs that are associated with prostate cancer relapse and alter their expression after RP, combined with genes that closely interact with selected miRNAs, has high potential for the prediction of PCa relapse after RP. PCa tissues and biofluids, both immediately after RP for diagnostics/prognostics and in long-term (relapse) monitoring, may be used as sources of these miRNAs.

CONCLUSION

An overview of the usefulness of published data and bioinformatics resources looking for diagnostic markers and molecular targets is presented in this article. The selected miRNA and gene panels have good potential as prognostic and PCa relapse markers after RP and likely could also serve as markers for therapeutic efficiency on a broader scale.

Non-Coding RNAs in Cancer Diagnosis and Therapy: Focus on Lung Cancer

Over the last several decades, clinical evaluation and treatment of lung cancers have largely improved with the classification of genetic drivers of the disease, such as EGFR, ALK, and ROS1. There are numerous regulatory factors that exert cellular control over key oncogenic pathways involved in lung cancers. In particular, non-coding RNAs (ncRNAs) have a diversity of regulatory roles in lung cancers such that they have been shown to be involved in inducing proliferation, suppressing apoptotic pathways, increasing metastatic potential of cancer cells, and acquiring drug resistance. The dysregulation of various ncRNAs in human cancers has prompted preclinical studies examining the therapeutic potential of restoring and/or inhibiting these ncRNAs. Furthermore, ncRNAs demonstrate tissue-specific expression in addition to high stability within biological fluids. This makes them excellent candidates as cancer biomarkers. This review aims to discuss the relevance of ncRNAs in cancer pathology, diagnosis, and therapy, with a focus on lung cancer.

miRNAs as Therapeutic Tools and Biomarkers for Prostate Cancer

Prostate cancer (PCa) is the fifth cause of tumor-related deaths in man worldwide. Despite the considerable improvement in the clinical management of PCa, several limitations emerged both in the screening for early diagnosis and in the medical treatment. The use of prostate-specific antigen (PSA)-based screening resulted in patients' overtreatment and the standard therapy of patients suffering from locally advanced/metastatic tumors (e.g., radical prostatectomy, radiotherapy, and androgen deprivation therapy) showed time-limited efficacy with patients undergoing progression toward the lethal metastatic castration-resistant PCa (mCRPC). Although valuable alternative therapeutic options have been recently proposed (e.g., docetaxel, cabazitaxel, abiraterone, enzalutamide, and sipuleucel-T), mCRPC remains incurable. Based on this background, there is an urgent need to identify new and more accurate prostate-specific biomarkers for PCa diagnosis and prognosis and to develop innovative medical approaches to counteract mCRPC. In this context, microRNA (miRNAs) emerged as potential biomarkers in prostate tissues and biological fluids and appeared to be promising therapeutic targets/tools for cancer therapy. Here we overview the recent literature and summarize the achievements of using miRNAs as biomarkers and therapeutic targets/tools for fighting PCa.

Therapeutic Targeting of MicroRNAs in the Tumor Microenvironment

The tumor-microenvironment (TME) is an amalgamation of various factors derived from malignant cells and infiltrating host cells, including cells of the immune system. One of the important factors of the TME is microRNAs (miRs) that regulate target gene expression at a post transcriptional level. MiRs have been found to be dysregulated in tumor as well as in stromal cells and they emerged as important regulators of tumorigenesis. In fact, miRs regulate almost all hallmarks of cancer, thus making them attractive tools and targets for novel anti-tumoral treatment strategies. Tumor to stroma cell cross-propagation of miRs to regulate protumoral functions has been a salient feature of the TME. MiRs can either act as tumor suppressors or oncogenes (oncomiRs) and both miR mimics as well as miR inhibitors (antimiRs) have been used in preclinical trials to alter cancer and stromal cell phenotypes. Owing to their cascading ability to regulate upstream target genes and their chemical nature, which allows specific pharmacological targeting, miRs are attractive targets for anti-tumor therapy. In this review, we cover a recent update on our understanding of dysregulated miRs in the TME and provide an overview of how these miRs are involved in current cancer-therapeutic approaches from bench to bedside.

A Novel Androgen-Induced lncRNA FAM83H-AS1 Promotes Prostate Cancer Progression via the miR-15a/CCNE2 Axis

Prostate cancer (PCa) is one of the most common types of tumors among males worldwide. However, the roles of long noncoding RNAs (lncRNAs) in PCa remain unclear. This study shows that lncRNA FAM83H-AS1 is upregulated in prostate adenocarcinoma, bladder urothelial carcinoma, and kidney renal papillary cell carcinoma samples. Androgen receptor (AR) signaling plays the most important role in PCa tumorigenesis and development. In this study, the results validate that AR signaling is involved in upregulating FAM83H-AS1 expression in PCa cells. Loss-of-function assays demonstrate that FAM83H-AS1 acts as an oncogene in PCa by modulating cell proliferation, cell cycle, and migration. Bioinformatics analysis demonstrates that FAM83H-AS1 is remarkably related to the regulation of the cell cycle and DNA replication through affecting multiple regulators related to these pathways, such as CCNE2. Mechanically, we found that FAM83H-AS1 plays its roles through sponging miR-15a to promote CCNE2 expression. These findings indicate that FAM83H-AS1 is a novel diagnostic and therapeutic marker for PCa.

Prognostic and Therapeutic Potentials of OncomiRs Modulating mTOR Pathways in Virus-Associated Hepatocellular Carcinoma

Background

Dysregulated oncomiRs are attributed to hepatocellular carcinoma (HCC) through targeting mTOR signaling pathway responsible for cell growth and proliferation. The potential of these oncomiRs as biomarker for tumor response or as target for therapy needs to be evaluated.

AIM

Tumor response assessment by OncomiR changes following locoregional therapy (LRT) and targeting of these oncomiRs modulating pathway

Methods

All consecutive viral-HCC patients of BCLC stage-A/B undergoing LRT were included. OncomiRs (miR-21, -221, and -16) change in circulation and AFP-ratio at 1-month post-LRT to baseline was estimated to differentiate various categories of response as per mRECIST criteria. OncomiR modulating mTOR pathway was studied by generating miR-21 and miR-221 overexpressing Huh7 stable cell lines.

Results

Post-LRT tumor response was assessed in 90 viral-HCC patients (CR, 40%; PR, 31%, and PD, 29%). Significant increase of miRNA-21 and -221 expression was observed in PD (p = 0.040, 0.047) and PR patients (miR-21, p = 0.045). Fold changes of miR-21 can differentiate response in group (CR from PR+PD) at AUROC 0.718 (95% CI, 0.572–0.799) and CR from PD at AUROC 0.734 (95% CI, 0.595–0.873). Overexpression of miR-21 in hepatoma cell line had shown increased phosphorylation p70S6K, the downstream regulator of cell proliferation in mTOR pathway. Upregulation of AKT, mTOR, and RPS6KB1 genes were found significant (P < 0.005) and anti-miR-21 specifically reduced mTOR gene (P = 0.02) expression.

Conclusions

The miR-21 fold change correlates well with imaging in predicting tumor response. Overexpression of miR-21 has a role in HCC through mTOR pathway activation and can be targeted.

The regulatory effect of 6-TG on lncRNA-miRNA-mRNA ceRNA network in triple-negative breast cancer cell line

Breast cancer is one of the most prevalent and recurring cancer types that leads to deaths in women. Triple-negative breast cancer (TNBC) is difficult to treat due to the lack of therapeutic targets. Many studies have focused on identifying drugs for use as alternative treatments for breast cancer. Thioguanine (6-TG) exerts antitumor effects in cancer. Increasing evidence has demonstrated that competitive endogenous ribonucleic acids (ceRNAs) are involved in cancer processes. However, the mechanism by which 6-TG regulates lncRNA-miRNA-mRNAs has not been elucidated. We evaluated the antitumor effect of 6-TG in MDA-MB-231 cells and comprehensively analyzed the RNA-Seq data of MDA-MB-231 cells treated with 6-TG. Our results showed that most tumor pathways were blocked by 6-TG. The hub genes were FN1, FLNA, FLNB, VCL, GSN, MYH10, ACTN4, KDR and EREG, and they were all down-regulated after 6-TG treatment. The coexpression network consisted of 18 microRNAs (miRNAs), 9 long noncoding RNAs (lncRNAs) and 20 mRNAs. Hsa-mir-16-5p and Hsa-mir-335-5p targeted the greatest number of mRNAs in the network. These molecules could bind to PAX8-AS1 and eliminate the inhibition of target mRNA expression. We showed that PAX8-AS1 is the main lncRNA affected by 6-TG and that PAX8-AS1 regulates the hub genes in tumor pathways by competitively binding with miR-16-5p and miR-335-5p.

Therapeutic advances of miRNAs: A preclinical and clinical update

miRNAs, a class of small endogenous RNAs, are one of the essential biopharmaceuticals which are in commercial spans as next-generation medicine in recent times. A snapshot of the current scenario regarding the miRNAs as biopharmaceuticals have been discussed. In this work, biopharmaceutical companies working with miRNAs and the current status of preclinical/clinical trials about miRNA therapeutics have been reviewed. Finally, recent updates on the absorption, distribution, metabolism, and excretion (ADME), as well as a delivery system of miRNAs, have been illustrated.

Reduced miR-16 levels are associated with VEGF upregulation in high-risk myelodysplastic syndromes

Objective: Overexpression of vascular endothelial growth factor (VEGF), a major angiogenic factor, was found in myelodysplastic syndromes (MDS) and showed different expression statuses in different risk groups of MDS. We aimed to investigate the possible role of microRNA (miR)-15a and miR-16 on the regulation of VEGF expression and their effect on angiogenesis in lower- and higher-risk MDS. Methods: We studied peripheral blood and bone marrow samples of MDS patients or several leukaemia and MDS cell lines by enzyme-linked immunosorbent assay, immunohistochemical staining, immunofluorescence and quantitative PCR for expression levels of VEGF, miR-15a and miR-16. MiRNA transfection and Luciferase reporter assays were conducted to investigate whether VEGF is a target of miR-16. Migration and tube formation assays were performed in cells exposed to medium from cells with overexpressed or knockdown miR-16. Results: It showed a significantly lower level of miR-16 in higher-risk MDS patients, while the VEGF levels were upregulated. Inverse correlation between VEGF and miR-16 were determined in cells lines including SKM-1, THP-1, and K562 cells. Overexpression of miR-16 in SKM-1 cells resulted in reduced VEGF secretion and cell protein levels. Direct binding of miR-16 to the 3' untranslated region (3'-UTR) of VEGF was confirmed by luciferase reporter assays. The migration and tube formation of human umbilical vein endothelial cells decreased in the presence of medium from SKM-1 cells with overexpressed miR-16. Conclusion: These data suggest that miR-16 may play a role in angiogenesis in higher-risk MDS by targeting VEGF and therefore modulating MDS progression. MiR-16 might be a novel therapeutic target in higher-risk MDS.

Co-delivery of miRNA-15a and miRNA-16-1 using cationic PEGylated niosomes downregulates Bcl-2 and induces apoptosis in prostate cancer cells

OBJECTIVE

Tumor suppressor miRNAs, miR-15a and miR-16-1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical application of free miRNAs include poor cellular uptake and instability in plasma, which can be partially improved by using nanocarriers to deliver anti-cancer agents to the tumor cell.

METHOD

In this study, cationic niosomes were designed and optimized with the specific formulation. Then, the physical characteristics, the cytotoxicity, the impact of transfected miRNAs on the expression of the Bcl-2 gene, and the apoptosis rate of the different formulation into prostate cancer cell were determined.

RESULTS

The optimum formulation containing tween-60: cholesterol: DOTAP: DSPE-PEG2000 at 70:30:25:5 demonstrated that the vesicle size and zeta potentials were 69.7 nm and + 14.83 mV, respectively. Additionally, noisome-loaded miRNAs had higher toxicity against cancer cells comparing with free forms. The transfection of PC3 cells with the combination therapy of nanocarriers loaded of two miRNAs led to a significant decrease in the expression of the Bcl-2 gene and increased the degree of cell death in PC3 cells compared with other treatment groups, and the synergistic effects of co-delivery of miR-15a and miR-16-1 on prostate cancer cells were shown.

CONCLUSION

According to the results, it seems the designed niosomes containing miR-15a and miR-16-1 can target the Bcl-2 gene and provide a cheap, applicable, cost-effective, and safe drug delivery system against prostate cancer.

Recent Advances in Nanomedicine for the Diagnosis and Treatment of Prostate Cancer Bone Metastasis

Patients with advanced prostate cancer can develop painful and debilitating bone metastases. Currently available interventions for prostate cancer bone metastases, including chemotherapy, bisphosphonates, and radiopharmaceuticals, are only palliative. They can relieve pain, reduce complications (e.g., bone fractures), and improve quality of life, but they do not significantly improve survival times. Therefore, additional strategies to enhance the diagnosis and treatment of prostate cancer bone metastases are needed. Nanotechnology is a versatile platform that has been used to increase the specificity and therapeutic efficacy of various treatments for prostate cancer bone metastases. In this review, we summarize preclinical research that utilizes nanotechnology to develop novel diagnostic imaging tools, translational models, and therapies to combat prostate cancer bone metastases.

M2-like tumor-associated macrophages-secreted Wnt1 and Wnt3a promotes dedifferentiation and metastasis via activating β-catenin pathway in thyroid cancer

BACKGROUND

Thyroid carcinoma (TC) has been a global issue for its rapid increasing incidence worldwide. Although most TC was not so aggressive with a good prognosis, treatment against anaplastic TC was relatively limited and the mechanisms are not well elucidated yet.

METHODS

TC cell lines (IHH4 and TPC-1) were used. Flow cytometry was used to identify the surface marker of M2-like tumor-associated macrophages (TAMs) from cell culture. Quantitative real-time polymerase chain reaction, western blot analysis, immunostaining, and immunohistochemistry were used to detect the expression of Wnt1, Wnt3a, components of Wnt/β-catenin pathway, and proliferation/epithelial-mesenchymal transition (EMT)-related proteins. Alkaline phosphatase activity assay, colony formation assay, and transwell assay were used to examine the roles of Wnt1, Wnt3a, and β-catenin pathway in cell dedifferentiation, proliferation, migration, and invasion of TC cells, respectively. Subcutaneous tumor growth was monitored in nude mice.

RESULTS

Coculture with M2-like TAMs facilitated dedifferentiation, proliferation, migration, and invasion in TC cells. EMT and proliferation-related proteins were also promoted in cocultured TC cells. The level of Wnt1 and Wnt3a was increased in the coculture system. Block of Wnt1 or Wnt3a suppressed malignant behaviors in cocultured tumor cells. Furthermore, Wnt1 or Wnt3a knockdown inhibited Wnt/β-catenin signaling pathway, and suppressed EMT and proliferation-related signals in cocultured tumor cells. Knockdown of Wnt1 or Wnt3a inhibited tumor growth in xenograft model.

CONCLUSION

M2-like TAMs promoted dedifferentiation, proliferation, and metastasis of TC by Wnt1 and Wnt3a secretion and ensuing β-catenin activation.

Cell-free DNA promotes malignant transformation in non-tumor cells

Cell-free DNA is present in different biological fluids and when released by tumor cells may contribute to pro-tumor events such as malignant transformation of cells adjacent to the tumor and metastasis. Thus, this study analyzed the effect of tumor cell-free DNA, isolated from the blood of prostate cancer patients, on non-tumor prostate cell lines (RWPE-1 and PNT-2). To achieve this, we performed cell-free DNA quantification and characterization assays, evaluation of gene and miRNA expression profiling focused on cancer progression and EMT, and metabolomics by mass spectrometry and cellular migration. The results showed that tumor-free cell DNA was able to alter the gene expression of MMP9 and CD44, alter the expression profile of nine miRNAs, and increased the tryptophan consumption and cell migration rates in non-tumor cells. Therefore, tumor cell-free DNA was capable of altering the receptor cell phenotype, triggering events related to malignant transformation in these cells, and can thus be considered a potential target for cancer diagnosis and therapy.

Comprehensive MicroRNA Expression Profile of the Mammary Gland in Lactating Dairy Cows With Extremely Different Milk Protein and Fat Percentages

A total of 31 differentially expressed genes in the mammary glands were identified in our previous study using RNA sequencing (RNA-Seq), for lactating cows with extremely high and low milk protein and fat percentages. To determine the regulation of milk composition traits, we herein investigated the expression profiles of microRNA (miRNA) using small RNA sequencing based on the same samples as in the previous RNA-Seq experiment. A total of 497 known miRNAs (miRBase, release 22.1) and 49 novel miRNAs among the reads were identified. Among these miRNAs, 71 were found differentially expressed between the high and low groups (p < 0.05, q < 0.05). Furthermore, 21 of the differentially expressed genes reported in our previous RNA-Seq study were predicted as target genes for some of the 71 miRNAs. Gene ontology and KEGG pathway analyses showed that these targets were enriched for functions such as metabolism of protein and fat, and development of mammary gland, which indicating the critical role of these miRNAs in regulating the formation of milk protein and fat. With dual luciferase report assay, we further validated the regulatory role of 7 differentially expressed miRNAs through interaction with the specific sequences in 3'UTR of the targets. In conclusion, the current study investigated the complexity of the mammary gland transcriptome in dairy cattle using small RNA-seq. Comprehensive analysis of differential miRNAs expression and the data from previous study RNA-seq provided the opportunity to identify the key candidate genes for milk composition traits.

mir15a/mir16-1 cluster and its novel targeting molecules negatively regulate cardiac hypertrophy

In response to pathological stimuli, the heart develops ventricular hypertrophy that progressively decompensates and leads to heart failure. miRNAs are increasingly recognized as pathogenic factors, clinically relevant biomarkers, and potential therapeutic targets. We identified that mir15a/mir16-1 cluster was negatively correlated with hypertrophic severity in patients with hypertrophic cardiomyopathy. The mir15a/mir16-1 expression was enriched in cardiomyocytes (CMs), decreased in hypertrophic human hearts, and decreased in mouse hearts after transverse aortic constriction (TAC). CM-specific mir15a/mir16-1 knockout promoted cardiac hypertrophy and dysfunction after TAC. CCAAT/enhancer binding protein (C/EBP)β was responsible for the downregulation of mir15a/mir16-1 cluster transcription. Mechanistically, mir15a/mir16-1 cluster attenuated the insulin/IGF1 signal transduction cascade by inhibiting multiple targets, including INSR, IGF-1R, AKT3, and serum/glucocorticoid regulated kinase 1 (SGK1). Pro-hypertrophic response induced by mir15a/mir16-1 inhibition was abolished by knockdown of insulin receptor (INSR), insulin like growth factor 1 receptor (IGF1R), AKT3, or SGK1. In vivo systemic delivery of mir15a/mir16-1 by nanoparticles inhibited the hypertrophic phenotype induced by TAC. Importantly, decreased serum mir15a/mir16-1 levels predicted the occurrence of left ventricular hypertrophy in a cohort of patients with hypertension. Therefore, mir15a/mir16-1 cluster is a promising therapeutic target and biomarker for cardiac hypertrophy.

The miR-93-3p/ZFP36L1/ZFX axis regulates keratinocyte proliferation and migration during skin wound healing

Keratinocyte proliferation and migration are crucial steps during skin wound healing. The functional role of microRNAs (miRs) remains relatively unknown during this process. miR-93 levels have been reported to increase within 24 h of skin wound healing; however, whether miR-93-3p or miR-93-5p plays a specific role in wound healing is yet to be studied. In this study, with the use of an in vivo mouse skin wound-healing model, we demonstrate that miR-93-3p is significantly upregulated, whereas there is no change in the expression of miR-93-5p during skin wound healing. In HaCaT cells, miR-93-3p overexpression increased proliferation and migration of the cells, whereas miR-93-3p inhibition had the reverse effect. Additionally, it was evident that ZFP36L1 was a direct target of miR-93-3p in keratinocytes. Further, ZFP36L1 silencing mirrored the consequences observed during miR-93-3p overexpression on both proliferation and migration of keratinocytes. In addition, we demonstrate that zinc-finger X-linked (ZFX), as a target for ZFP36L1, is involved in the promotion of the miR-93-3p/ZFP36L1 axis in keratinocyte proliferation and migration. Ultimately, we found that mouse skin wound model treatment with anti-miR-93-3p delayed wound healing. Overall, our results show that miR-93-3p is a crucial regulator of skin wound healing that facilitates keratinocyte proliferation and migration through ZFP36L1/ZFX axis.

microRNAs deregulation in head and neck squamous cell carcinoma

Head and neck (HN) squamous cell carcinoma (SCC) is the eighth most common human cancer worldwide. Besides tobacco and alcohol consumption, genetic and epigenetic alterations play an important role in HNSCC occurrence and progression. microRNAs (miRNAs) are small noncoding RNAs that regulate cell cycle, proliferation, development, differentiation, and apoptosis by interfering in gene expression. Expression profiling of miRNAs showed that some miRNAs are upregulated or downregulated in tumor cells when compared with the normal cells. The present review focuses on the role of miRNAs deregulations in HNSCC, enrolled in risk, development, outcome, and therapy sensitivity. Moreover, the influence of single nucleotide variants in miRNAs target sites, miRNAs seed sites, and miRNAs-processing genes in HNSCC was also revised. Due to its potential for cancer diagnosis, progression, and as a therapeutic target, miRNAs may bring new perspectives in HNSCC understanding and therapy, especially for those patients with no or insufficient treatment options.

TGF-β1-regulated miR-3691-3p targets E2F3 and PRDM1 to inhibit prostate cancer progression

Transforming growth factor-β1 (TGF-β1) acts as a tumor promoter in advanced prostate cancer (PCa). We speculated that microRNAs (miRNAs) that are inhibited by TGF-β1 might exert anti-tumor effects. To assess this, we identified several miRNAs downregulated by TGF-β1 in PCa cell lines and selected miR-3691-3p for detailed analysis as a candidate anti-oncogene miRNA. miR-3691-3p was expressed at significantly lower levels in human PCa tissue compared with paired benign prostatic hyperplasia tissue, and its expression level correlated inversely with aggressive clinical pathological features. Overexpression of miR-3691-3p in PCa cell lines inhibited proliferation, migration, and invasion, and promoted apoptosis. The miR-3691-3p target genes E2F transcription factor 3 (E2F3) and PR domain containing 1, with ZNF domain (PRDM1) were upregulated in miR-3691-3p-overexpressing PCa cells, and silencing of E2F3 or PRDM1 suppressed PCa cell proliferation, migration, and invasion. Treatment of mice bearing PCa xenografts with a miR-3691-3p agomir inhibited tumor growth and promoted tumor cell apoptosis. Consistent with the negative regulation of E2F3 and PRDM1 by miR-3691-3p, both proteins were overexpressed in clinical PCa specimens compared with noncancerous prostate tissue. Our results indicate that TGF-β1-regulated miR-3691-3p acts as an anti-oncogene in PCa by downregulating E2F3 and PRDM1. These results provide novel insights into the mechanisms by which TGF-β1 contributes to the progression of PCa.

MicroRNA: Promising Roles in Cancer Therapy

MicroRNAs (miRNA) are small non-coding RNAs that act as one of the main regulators of gene expression. They are involved in maintaining a proper balance of diverse processes, including differentiation, proliferation, and cell death in normal cells. Cancer biology can also be affected by these molecules by modulating the expression of oncogenes or tumor suppressor genes. Thus, miRNA based anticancer therapy is currently being developed either alone or in combination with chemotherapy agents used in cancer management, aiming at promoting tumor regression and increasing cure rate. Access to large quantities of RNA agents can facilitate RNA research and development. In addition to currently used in vitro methods, fermentation-based approaches have recently been developed, which can cost-effectively produce biological RNA agents with proper folding needed for the development of RNA-based therapeutics. Nevertheless, a major challenge in translating preclinical studies to clinical for miRNA-based cancer therapy is the efficient delivery of these agents to target cells. Targeting miRNAs/anti-miRNAs using antibodies and/or peptides can minimize cellular and systemic toxicity. Here, we provide a brief review of miRNA in the following aspects: biogenesis and mechanism of action of miRNAs, the role of miRNAs in cancer as tumor suppressors or oncogenes, the potential of using miRNAs as novel and promising therapeutics, miRNA-mediated chemo-sensitization, and currently utilized methods for the in vitro and in vivo production of RNA agents. Finally, an update on the viral and non-viral delivery systems is addressed.

MicroRNA-16 Inhibits Glioblastoma Growth in Orthotopic Model by Targeting Cyclin D1 and WIP1

Introduction

To examine the molecular mechanism by which miRNA-16 (miR-16) suppresses glioblastoma in vitro and in vivo.

Methods

Gene expression of miR-16 in normal brain tissues and human glioma cell lines was examined. To characterize the functional role of miR-16 in vitro, miR-16 was ectopically expressed in U87 cells by lentiviral transduction. Expression of miR-16 downstream targets cyclin D1 and Bcl-2 in U87 was studied using Western blotting. Cell proliferation and clonogenic property were examined using CCK-8 and clone formation assay, respectively. Migration and invasiveness of U87 was studied using wound-healing assay and transwell assay, respectively. In vivo tumorigenic properties of the miR-16-transduced U87 cells were examined in an orthotopic xenograft model. Immunohistochemistry was performed to examine cyclin D1, WIP1 and CD31 expressions.

Results

Expression of miR-16 was reduced in glioblastoma cell lines compared to normal human brain tissues. Ectopic miR-16 expression reduced cyclin D1 and Bcl-2 in U87 cells. miR-16 also induced apoptosis, reduced cell proliferation and clone formation. Furthermore, miR-16 suppressed U87 migration in wound-healing assay and invasion across transwell membrane in vitro. In an orthotopic tumor model, overexpression of miR-16 inhibited tumor growth in vivo was accompanied with reduction in cyclin D1 and WIP1 expression in the xenografts. CD31 expression in miR-16-overexpressed xenografts was also decreased. The determined microvessel density of the miR-16 overexpression group was significantly lower than those groups treated with vehicle and empty vector.

Discussion

MicroRNA-16 exhibits inhibitory effects of glioblastoma. MicroRNA-16 and its downstream targets could be potential therapeutic targets for treatment of glioblastoma.

LncRNA CDKN2B-AS1 relieved inflammation of ulcerative colitis via sponging miR-16 and miR-195

BACKGROUND

This study was aimed to explore the differential expression of lncRNA CDKN2B-AS1-miR-195-5p/miR-16-5p axis in ulcerative colitis (UC) and its role in regulating UC pathogenesis.

METHODS

One hundred and eighty-seven UC patients and one hundred and fifty-two healthy volunteers were recruited, and their blood samples were collected. Inflammatory cytokines in serum were determined with ELISA, and lncRNA CDKN2B-AS1, miR-195-5p and miR-16-5p levels were detected with RT-PCR. Then pcDNA3.1-CDKN2B-AS1, si-CDKN2B-AS1, miR-195-5p mimic, miR-195-5p inhibitor, miR-16-5p mimic and miR-16-5p inhibitor were transfected into HT29 cells, and proliferation and apoptosis of the cells were assessed. Dual-luciferase reporter gene assay was implemented to identify the sponging relationship between lncRNA CDKN2B-AS1 and miR-195-5p/miR-16-5p.

RESULTS

CDKN2B-AS1 level was negatively correlated with levels of inflammatory cytokines, including TNF-α, IL-6 and sIL-2R, yet miR-16-5p and miR-195-5p levels were negatively correlated with the CDKN2B-AS1 level. The CDKN2B-AS1 combined with miR-16-5p and miR-195-5p also achieved an optimum efficacy in differentiating between light and medium UC, light and severe UC, as well as medium and heavy UC. Furthermore, pcDNA3.1-CDKN2B-AS1 depressed expressions of IFN-γ, IL-8, IL-1β and TNF-α in HT29 cells (P < 0.05), and strengthened proliferation of the cells (P < 0.05). CDKN2B-AS1 also sponged and regulated miR-16-5p and miR-195-5p in HT29 cells, and miR-16-5p and miR-195-5p could reverse the effect of CDKN2B-AS1 on inflammatory cytokine production, barrier function and apoptosis of HT29 cells (P < 0.05).

CONCLUSION

LncRNA CDKN2B-AS1 regulated inflammation of UC by sponging miR-195-5p and miR-16-5p, providing an alternative for diagnosis and treatment of UC.