Evaluation of miRNA-21 and miRNA Let-7 as Prognostic Markers in Patients With Breast Cancer

Intelligent Cell Profiling and Precision Release: Multimolecular Marker-Activated Transmembrane DNA Computing Nanosystem

Accurate classification of tumor cells is of importance for cancer diagnosis and further therapy. In this study, we develop multimolecular marker-activated transmembrane DNA computing systems (MTD). Employing the cell membrane as a native gate, the MTD system enables direct signal output following simple spatial events of "transmembrane" and "in-cell target encounter", bypassing the need of multistep signal conversion. The MTD system comprises two intelligent nanorobots capable of independently sensing three molecular markers (MUC1, EpCAM, and miR-21), resulting in comprehensive analysis. Our AND-AND logic-gated system (MTDAND-AND) demonstrates exceptional specificity, allowing targeted release of drug-DNA specifically in MCF-7 cells. Furthermore, the transformed OR-AND logic-gated system (MTDOR-AND) exhibits broader adaptability, facilitating the release of drug-DNA in three positive cancer cell lines (MCF-7, HeLa, and HepG2). Importantly, MTDAND-AND and MTDOR-AND, while possessing distinct personalized therapeutic potential, share the ability of outputting three imaging signals without any intermediate conversion steps. This feature ensures precise classification cross diverse cells (MCF-7, HeLa, HepG2, and MCF-10A), even in mixed populations. This study provides a straightforward yet effective solution to augment the versatility and precision of DNA computing systems, advancing their potential applications in biomedical diagnostic and therapeutic research.

Role of MicroRNA in Hypoxic Tumours and their Potential as Biomarkers for Early Detection of Cancer

Hypoxia is a pathophysiological condition characterized by oxygen deficiency in tissues, which negatively affects normal biological functions. It is a typical microenvironment character of almost all solid tumours. Noncoding RNA are small functional RNA molecules that regulate gene expression at chromatin and posttranscriptional levels. Micro-RNAs (miRNAs) are a type of noncoding RNA and are ~12-22 nucleotides long that are crucial in regulating gene expression by partnering with the mRNAs of protein-coding genes. It is widely reported that miRs play an important role in various key processes and pathways during tumour formation, as well as advancement in hypoxic tumors by influencing the HIF pathway. The role of miRNAs in hypoxic tumours, namely in pancreatic, kidney, breast, lung and colorectal, are described. These miRNAs have immense potential as diagnostic and prognostic biomarkers for early cancer detection.

Interfacial Profiling of MicroRNAs at Patterned Nanogaps for an Integrated Microfluidic-SERS Liquid Biopsy

A versatile microfluidic-SERS barcoding system is developed for sensitive and multiplexed imaging of circulating microRNAs through interfacial probing of encoded nanorod aggregates at diverse patterned nanogaps. The use of a single-layer, vertically oriented nanorod array creates a plasmonic coupling-based electromagnetic field with enormously enhanced Raman outputs. The introduction of the herringbone micromixer with circulated microflow sampling accelerates the hybridization and capture of nanorod aggregates on the plasmonic substrate. The method is able to achieve ideal sensitivities at subfemtomolar levels for four miRNAs, with multiplexed assay capability for an integrated liquid biopsy. The on-chip digital profiling of serum miRNAs in mapping and barcoding formats enable both clear discrimination of untreated cancer patients from the healthy cohort and precise classification of tumor stages, metastatic conditions, and subtypes, with an overall accuracy of 94%. The SERS-based microfluidic barcoding system therefore holds great promise in early cancer screening, diagnosis, and prognosis.

Regulation and signaling pathways in cancer stem cells: implications for targeted therapy for cancer

Cancer stem cells (CSCs), initially identified in leukemia in 1994, constitute a distinct subset of tumor cells characterized by surface markers such as CD133, CD44, and ALDH. Their behavior is regulated through a complex interplay of networks, including transcriptional, post-transcriptional, epigenetic, tumor microenvironment (TME), and epithelial-mesenchymal transition (EMT) factors. Numerous signaling pathways were found to be involved in the regulatory network of CSCs. The maintenance of CSC characteristics plays a pivotal role in driving CSC-associated tumor metastasis and conferring resistance to therapy. Consequently, CSCs have emerged as promising targets in cancer treatment. To date, researchers have developed several anticancer agents tailored to specifically target CSCs, with some of these treatment strategies currently undergoing preclinical or clinical trials. In this review, we outline the origin and biological characteristics of CSCs, explore the regulatory networks governing CSCs, discuss the signaling pathways implicated in these networks, and investigate the influential factors contributing to therapy resistance in CSCs. Finally, we offer insights into preclinical and clinical agents designed to eliminate CSCs.

A dual-ratio fluorescent probe with a single excitation triple-signal to synchronously detect PTK7 and miRNA-21 for breast cancer early diagnosis

The measurement of tumor biomarker levels is of great significance for early diagnosis of breast cancer. The combination diagnosis of multiple tumor biomarkers will significantly improve the accuracy of early diagnosis. Here, we successfully developed a dual-ratio fluorescent sensing platform for the detection of breast cancer biomarkers (PTK7, miRNA-21) using single excitation triple-signal detection. Introducing three types of fluorescence nanomaterials with narrow emission peaks and long Stokes shift as signal markers, the three peaks (430 nm, 530 nm and 640 nm) of which do not interfere with each other in fluorescence spectra under a single excitation (360 nm). The sensing platform linked aptamer (apt) modified green fluorescence quantum dots (gQDs-apt1) and aptamer modified red fluorescence quantum dots (rQDs-apt2) to Fe3O4-cDNA1 and Fe3O4-cDNA2, respectively, via base complementary pairing with aptamer molecules. When PTK7/miRNA-21 is present in the system, gQDs-apt1/rQDs-apt2 bound to the Fe3O4 MNPs surface will be released to recover fluorescence. Upon DNase I digestion of free apt1 and apt2, the target molecules will be released to bind to gQDs-apt1/rQDs-apt2 for signal amplification. After magnetic separation, PTK7 and miRNA-21 can be quantified using the fluorescence intensity ratio of gQDs with bCDs and rQDs with bCDs at a single excitation of 360 nm wavelength. This method has high sensitivity, good selectivity, and can quantify both PTK7 and miRNA-21 simultaneously with an LOD of 0.426 ng mL-1 and 0.072 nM, respectively. Additionally, the sensing platform was used for serum detection of health man and breast cancer patients with satisfactory results.

Circulating biomarkers at diagnosis correlate with distant metastases of early luminal-like breast cancer

There is an urgent need for new and better biomarker modalities to estimate the risk of recurrence within the luminal-like breast cancer (BC) population. Molecular diagnostic tests used in the clinic lack accuracy in identifying patients with early luminal BC who are likely to develop metastases. This study provides proof of concept that various liquid biopsy read-outs could serve as valuable candidates to build a multi-modal biomarker model distinguishing, already at diagnosis, between early metastasizing and non-metastasizing patients. All these blood biomarkers (chemokines, microRNAs, leukemia inhibitory factor, osteopontin, and serum-induced functional myeloid signaling responses) can be measured in baseline plasma/serum samples and could be added to the existing prognostic factors to improve risk stratification and more patient-tailored treatment in early luminal BC.

Three Strategies in Engineering Nanomedicines for Tumor Microenvironment-Enabled Phototherapy

Canonical phototherapeutics have several limitations, including a lack of tumor selectivity, nondiscriminatory phototoxicity, and tumor hypoxia aggravation. The tumor microenvironment (TME) is characterized by hypoxia, acidic pH, and high levels of H2 O2 , GSH, and proteases. To overcome the shortcomings of canonical phototherapy and achieve optimal theranostic effects with minimal side effects, unique TME characteristics are employed in the development of phototherapeutic nanomedicines. In this review, the effectiveness of three strategies for developing advanced phototherapeutics based on various TME characteristics is examined. The first strategy involves targeted delivery of phototherapeutics to tumors with the assistance of TME-induced nanoparticle disassembly or surface modification. The second strategy involves near-infrared absorption increase-induced phototherapy activation triggered by TME factors. The third strategy involves enhancing therapeutic efficacy by ameliorating TME. The functionalities, working principles, and significance of the three strategies for various applications are highlighted. Finally, possible challenges and future perspectives for further development are discussed.

Breast cancer: miRNAs monitoring chemoresistance and systemic therapy

With a high mortality rate that accounts for millions of cancer-related deaths each year, breast cancer is the second most common malignancy in women. Chemotherapy has significant potential in the prevention and spreading of breast cancer; however, drug resistance often hinders therapy in breast cancer patients. The identification and the use of novel molecular biomarkers, which can predict response to chemotherapy, might lead to tailoring breast cancer treatment. In this context, accumulating research has reported microRNAs (miRNAs) as potential biomarkers for early cancer detection, and are conducive to designing a more specific treatment plan by helping analyze drug resistance and sensitivity in breast cancer treatment. In this review, miRNAs are discussed in two alternative ways-as tumor suppressors to be used in miRNA replacement therapy to reduce oncogenesis and as oncomirs to lessen the translation of the target miRNA. Different miRNAs like miR-638, miR-17, miR-20b, miR-342, miR-484, miR-21, miR-24, miR-27, miR-23 and miR-200 are involved in the regulation of chemoresistance through diverse genetic targets. For instance, tumor-suppressing miRNAs like miR-342, miR-16, miR-214, and miR-128 and tumor-promoting miRNAs like miR101 and miR-106-25 cluster regulate the cell cycle, apoptosis, epithelial to mesenchymal transition and other pathways to impart breast cancer drug resistance. Hence, in this review, we have discussed the significance of miRNA biomarkers that could assist in providing novel therapeutic targets to overcome potential chemotherapy resistance to systemic therapy and further facilitate the design of tailored therapy for enhanced efficacy against breast cancer.

Analysis of circulating extracellular vesicle derived microRNAs in breast cancer patients with obesity: a potential role for Let-7a

BACKGROUND

The incidence of obesity, a known risk factor for several metabolic and chronic diseases, including numerous malignancies, has risen sharply in the world. Various clinical studies demonstrate that excessive Body Mass Index (BMI) may worsen the incidence, prognosis, and mortality rates of breast cancer. Thus, understanding the link tying up obesity and breast cancer onset and progression is critically important, as it can impact patients' survival and quality of life. Recently, circulating extracellular vesicle (EV) derived miRNAs have attracted much attention for their diagnostic, prognostic and therapeutic potential in oncology research. Although the potential role of EV-derived miRNAs in the early detection of breast cancer has been repeatedly mentioned, screening of miRNAs packaged within serum EVs has not yet been reported in patients with obesity.

METHODS

Circulating EVs were isolated from normal weight (NW), and overweight/obese (OW/Ob) breast cancer patients and characterized by Transmission Electron Microscopy (TEM), Nanoparticle Tracking Analysis (NTA), and protein marker expression. Evaluation of EV-associated miRNAs was conducted in a screening (RNA-seq) and a validation (qRT-PCR) cohort. Bioinformatic analysis was performed to uncover significantly enriched biological processes, molecular functions and pathways. ROC and Kaplain-Meier survival analyses were used for clinical significance.

RESULTS

Comparison of serum EV-derived miRNAs from NW and OW/Ob patients detected seven differentially expressed miRNAs (let-7a-5p, miR-122-5p, miR-30d-5p, miR-126-3p, miR-27b-3p, miR-4772-3p, and miR-10a-5p) in the screening cohort. GO analysis revealed the enrichment of protein phosphorylation, intracellular signal transduction, signal transduction, and vesicle-mediated transport among the top biological processes. In addition, the target genes were significantly enriched in pathways related to PI3K/Akt, growth hormones, and insulin signalings, which are all involved in obesity-related diseases and/or breast cancer progression. In the validation cohort, qRT-PCR confirmed a significant down-regulation of EV-derived let-7a in the serum of OW/Ob breast cancer patients compared to NW patients. Let-7a levels also exhibited a negative correlation with BMI values. Importantly, decreased let-7a miRNA expression was associated with higher tumor grade and poor survival in patients with breast cancer.

CONCLUSION

These results suggest that serum-EV derived miRNAs may reflect a differential profile in relation to a patient's BMI, which, once validated in larger cohorts of patients, could provide insights into novel specific biomarkers and innovative targets to prevent the progression of obesity-mediated breast cancer.

An overview of biochemical technologies for the cancer biomarker miR-21 detection

In recent years, the incidence of cancer has continuously increased, in which various miRNAs have been proposed as biomarkers for the early screening of cancer patients. As a consequence, the development of accurate methods for miRNA quantification has become a major research challenge worldwide. As one of the first discovered oncogenic miRNAs, microRNA-21 (miR-21) has been highlighted for its critical role in cancers. This review describes the main techniques currently available for miR-21 detection, compares the differences of the methods and the amplification strategies, and provides an overview of the state of knowledge in the field.

Prognostic and diagnostic values of non-coding RNAs as biomarkers for breast cancer: An umbrella review and pan-cancer analysis

Background: Breast cancer (BC) is the most common cancer in women. The incidence and morbidity of BC are expected to rise rapidly. The stage at which BC is diagnosed has a significant impact on clinical outcomes. When detected early, an overall 5-year survival rate of up to 90% is possible. Although numerous studies have been conducted to assess the prognostic and diagnostic values of non-coding RNAs (ncRNAs) in breast cancer, their overall potential remains unclear. In this field of study, there are various systematic reviews and meta-analysis studies that report volumes of data. In this study, we tried to collect all these systematic reviews and meta-analysis studies in order to re-analyze their data without any restriction to breast cancer or non-coding RNA type, to make it as comprehensive as possible. Methods: Three databases, namely, PubMed, Scopus, and Web of Science (WoS), were searched to find any relevant meta-analysis studies. After thoroughly searching, the screening of titles, abstracts, and full-text and the quality of all included studies were assessed using the AMSTAR tool. All the required data including hazard ratios (HRs), sensitivity (SENS), and specificity (SPEC) were extracted for further analysis, and all analyses were carried out using Stata. Results: In the prognostic part, our initial search of three databases produced 10,548 articles, of which 58 studies were included in the current study. We assessed the correlation of non-coding RNA (ncRNA) expression with different survival outcomes in breast cancer patients: overall survival (OS) (HR = 1.521), disease-free survival (DFS) (HR = 1.33), recurrence-free survival (RFS) (HR = 1.66), progression-free survival (PFS) (HR = 1.71), metastasis-free survival (MFS) (HR = 0.90), and disease-specific survival (DSS) (HR = 0.37). After eliminating low-quality studies, the results did not change significantly. In the diagnostic part, 22 articles and 30 datasets were retrieved from 8,453 articles. The quality of all studies was determined. The bivariate and random-effects models were used to assess the diagnostic value of ncRNAs. The overall area under the curve (AUC) of ncRNAs in differentiated patients is 0.88 (SENS: 80% and SPEC: 82%). There was no difference in the potential of single and combined ncRNAs in differentiated BC patients. However, the overall potential of microRNAs (miRNAs) is higher than that of long non-coding RNAs (lncRNAs). No evidence of publication bias was found in the current study. Nine miRNAs, four lncRNAs, and five gene targets showed significant OS and RFS between normal and cancer patients based on pan-cancer data analysis, demonstrating their potential prognostic value. Conclusion: The present umbrella review showed that ncRNAs, including lncRNAs and miRNAs, can be used as prognostic and diagnostic biomarkers for breast cancer patients, regardless of the sample sources, ethnicity of patients, and subtype of breast cancer.

Comprehensive multi-omics analysis of the m7G in pan-cancer from the perspective of predictive, preventive, and personalized medicine

Background

The N7-methylguanosine modification (m7G) of the 5' cap structure in the mRNA plays a crucial role in gene expression. However, the relation between m7G and tumor immune remains unclear. Hence, we intended to perform a pan-cancer analysis of m7G which can help explore the underlying mechanism and contribute to predictive, preventive, and personalized medicine (PPPM / 3PM).

Methods

The gene expression, genetic variation, clinical information, methylation, and digital pathological section from 33 cancer types were downloaded from the TCGA database. Immunohistochemistry (IHC) was used to validate the expression of the m7G regulator genes (m7RGs) hub-gene. The m7G score was calculated by single-sample gene-set enrichment analysis. The association of m7RGs with copy number variation, clinical features, immune-related genes, TMB, MSI, and tumor immune dysfunction and exclusion (TIDE) was comprehensively assessed. CellProfiler was used to extract pathological section characteristics. XGBoost and random forest were used to construct the m7G score prediction model. Single-cell transcriptome sequencing (scRNA-seq) was used to assess the activation state of the m7G in the tumor microenvironment.

Results

The m7RGs were highly expressed in tumors and most of the m7RGs are risk factors for prognosis. Moreover, the cellular pathway enrichment analysis suggested that m7G score was closely associated with invasion, cell cycle, DNA damage, and repair. In several cancers, m7G score was significantly negatively correlated with MSI and TMB and positively correlated with TIDE, suggesting an ICB marker potential. XGBoost-based pathomics model accurately predicts m7G scores with an area under the ROC curve (AUC) of 0.97. Analysis of scRNA-seq suggests that m7G differs significantly among cells of the tumor microenvironment. IHC confirmed high expression of EIF4E in breast cancer. The m7G prognostic model can accurately assess the prognosis of tumor patients with an AUC of 0.81, which was publicly hosted at https://pan-cancer-m7g.shinyapps.io/Panca-m7g/.

Conclusion

The current study explored for the first time the m7G in pan-cancer and identified m7G as an innovative marker in predicting clinical outcomes and immunotherapeutic efficacy, with the potential for deeper integration with PPPM. Combining m7G within the framework of PPPM will provide a unique opportunity for clinical intelligence and new approaches.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00305-1.

A novel conductive nanocomposite-based biosensor for ultrasensitive detection of microRNA-21 in serum, using methylene blue as mediator

MicroRNA-21 (miRNA-21) is a common biomarker with high expression in breast tumors. Therefore, sensitive detection of miRNA-21 is of great significance for clinical breast tumor diagnosis. A TH/rGO/CMK-3/AuNPs nanocomposite is composed of thionine (TH), reduced graphene oxide (rGO), ordered mesoporous carbon (CMK-3), and gold nanoparticles (AuNPs), which help to increase the specific surface area of a glassy carbon electrode (GCE) and to amplify the DPV signal. Meanwhile, methylene blue (MB) was combined with the capture probe guanine and absorbed by the composite material to mediate the differential pulse voltammetry (DPV) of the obtained miRNA biosensor. The current response decreased with increasing miRNA-21 concentration under optimal conditions. The biosensor responds to miRNA-21 in the 0.1fM-1 pM concentration range, and the detection limit (LOD) was 0.046 fM. Moreover, human serum samples were effectively detected utilizing the miRNA-21 biosensor with satisfactory results.

Potential utility of miRNAs for liquid biopsy in breast cancer

Breast cancer (BC) remains the most prevalent malignancy due to its incidence rate, recurrence, and metastasis in women. Conventional strategies of cancer detection– mammography and tissue biopsy lack the capacity to detect the complete cancer genomic landscape. Besides, they often give false- positive or negative results. The presence of this and other disadvantages such as invasiveness, high-cost, and side effects necessitates developing new strategies to overcome the BC burden. Liquid biopsy (LB) has been brought to the fore owing to its early detection, screening, prognosis, simplicity of the technique, and efficient monitoring. Remarkably, microRNAs (miRNAs)– gene expression regulators seem to play a major role as biomarkers detected in the samples of LB. Particularly, miR-21 and miR-155 among other possible candidates seem to serve as favorable biomarkers in the diagnosis and prognosis of BC. Hence, this review will assess the potential utility of miRNAs as biomarkers and will highlight certain promising candidates for the LB approach in the diagnosis and management of BC that may optimize the patient outcome.

The Targeting of Noncoding RNAs by Quercetin in Cancer Prevention and Therapy

The dietary flavonoid quercetin is ubiquitously distributed in fruits, vegetables, and medicinal herbs. Quercetin has been a focal point in recent years due to its versatile health-promoting benefits and high pharmacological values. It has well documented that quercetin exerts anticancer actions by inhibiting cell proliferation, inducing apoptosis, and retarding the invasion and metastasis of cancer cells. However, the exact mechanism of quercetin-mediated cancer chemoprevention is still not fully understood. With the advances in high-throughput sequencing technologies, the intricate oncogenic signaling networks have been gradually characterized. Increasing evidence on the close association between noncoding RNA (ncRNAs) and cancer etiopathogenesis emphasizes the potential of ncRNAs as promising molecular targets for cancer treatment. Available experimental studies indicate that quercetin can dominate multiple cancer-associated ncRNAs, hence repressing carcinogenesis and cancer development. Thus, modulation of ncRNAs serves as a key mechanism responsible for the anticancer effects of quercetin. In this review, we focus on the chemopreventive effects of quercetin on cancer pathogenesis by targeting cancer-relevant ncRNAs, supporting the viewpoint that quercetin holds promise as a drug candidate for cancer chemoprevention and chemotherapy. An in-depth comprehension of the interplay between quercetin and ncRNAs in the inhibition of cancer development and progression will raise the possibility of developing this bioactive compound as an anticancer agent that could be highly efficacious and safe in clinical practice.

MicroRNAs as therapeutic targets in breast cancer metastasis

Breast cancer is a complex disease with multiple risk factors involved in its pathogenesis. Among these factors, microRNAs are considered for playing a fundamental role in the development and progression of malignant breast tumors. In recent years, various studies have demonstrated that several microRNAs exhibit increased or decreased expression in metastatic breast cancer, acting as indicators of metastatic potential in body fluids and tissue samples. The identification of these microRNA expression patterns could prove instrumental for the development of novel therapeutic molecules that either mimic or inhibit microRNA action. Additionally, an efficient delivery system mediated by viral vectors, nonviral carriers, or scaffold biomaterials is a prerequisite for implementing microRNA-based therapies; therefore, this review attempts to highlight essential microRNA molecules involved in the metastatic process of breast cancer and discuss recent advances in microRNA-based therapeutic approaches with potential future applications to the treatment sequence of breast cancer.

Interstitial Fluid Biomarkers' Minimally Invasive Monitoring Using Microneedle Sensor Arrays

Skin interstitial fluid (ISF) is a biofluid with information-rich biomarkers for disease diagnosis and prognosis. Microneedle (MN) integration of sampling and instant biomarker readout hold great potential in health status monitoring and point-of-care testing (POCT). The present work describes an attractive MN sensor array for minimally invasive monitoring of ISF microRNA (miRNA) and Cu²⁺. The MN array is made of methacrylated gelatin (GelMA) and methacrylated hyaluronic acid (MeHA), and a further divisionally encapsulated miRNA and Cu²⁺ detection system, and is cross-linked through blue-light irradiation. The MN patch displays good mechanical properties that enable withstanding more than 0.4 N per needle, and exhibits a high swelling ratio of 700% that facilitates timely extraction of sufficient ISF for biomarker analysis. For proof-of-concept, it realizes detection of miRNAs and Cu²⁺ efficiently and quantitatively in an agarose skin and fresh porcine cadaver skin model. Given the good sampling and in situ monitoring ability, the MN array holds great promise for skin ISF-based applications.

Long non-coding RNA LOC366613 alleviates the cerebral ischemic injury via regulating the miR-532-5p/phosphatase and tensin homolog axis

Cerebral infarction (CI) has become a leading cause of death in China. Long non-coding RNAs (lncRNAs) are intensively involved in the progression of CI. Here, we aimed to investigate the effects of lncRNA LOC366613 (LOC366613) on cerebral I/R injury, as well as its possible mechanism. Transient middle cerebral artery occlusion (MCAO) was used to establish a mouse model of cerebral I/R, and the PC12 cell line was used to establish an in vitro oxygen-glucose deprivation (OGD) injury model. The MTT assay was used to determine cell viability, and qRT-PCR was used to determine RNA levels. Western blotting was conducted to detect protein expression levels. The TUNEL assay and flow cytometry were used to measure cell apoptosis, and 2,3,5-triphenyltetrazolium chloride (TTC) was used to determine cerebral infarct volume. Finally, RNA pull-down and luciferase activity assays were used to examine interactions between miR-532-5p and LOC366613, as well as between miR-532-5p and phosphatase and tensin homolog (PTEN). LOC366613 was overexpressed in patients with cerebral I/R injury. In PC12 cells, knockdown of LOC366613 reduced the apoptosis rate and lactic acid dehydrogenase (LDH) expression, while increasing cell viability. Moreover, miR-532-5p was shown to be a target of LOC366613, as predicted. Downregulation of miR-532-5p reversed the effects of LOC366613 knockdown on PC12 cell apoptosis, LDH release, and cell viability. Finally, PTEN was verified as a target of miR-532-5p. LOC366613 participates in cerebral I/R injury by regulating the miR-532-5p/PTEN axis, potentially providing a new CI treatment target.

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.

Resistin Induces LIN28A-Mediated Let-7a Repression in Breast Cancer Cells Leading to IL-6 and STAT3 Upregulation

Simple Summary

Breast cancer is the second leading cause of cancer-related death in women in the United States and exhibits significant racial disparities in clinical outcomes. Earlier, we reported that the levels of resistin and IL-6 were significantly more elevated in the serum of African American women with breast cancer than in their Caucasian American counterparts. Here, we uncover its mechanistic significance by characterizing a novel resistin/LIN28A/Let-7a/IL-6/STAT3 signaling axis supporting the growth and stemness of breast cancer cells.

Abstract

Downregulation of the Let-7 family of microRNAs (miRNAs) has been reported in several cancers, including breast malignancy; however, underlying mechanisms are not completely understood. Resistin is an important component of the tumor microenvironment, having a functional impact on the tumor cell phenotypes. Here, we examined the role of resistin in the regulation of Let-7 miRNAs and studied its downstream consequences. We found that resistin treatment led to the reduced expression of Let-7 family miRNAs in breast cancer (BC) cells, with the highest downregulation reported for Let-7a. Furthermore, resistin induced the expression of LIN28A, and its silencing abrogated resistin-mediated Let-7a suppression. Let-7a restoration or LIN28A silencing abolished the resistin-induced growth, clonogenicity, and sphere-forming ability of BC cells. Restoration of Let-7a also suppressed the resistin-induced expression of genes associated with growth, survival, and stemness. Pathway analysis suggested STAT3 as a putative central node associated with Let-7a-mediated gene regulation. In silico analysis identified STAT3 and its upstream modifier, IL-6, as putative Let-7a gene targets, which were later confirmed by 3′UTR-reporter assays. Together, our findings demonstrate a novel resistin/LIN28A/Let-7a/IL-6/STAT3 signaling axis supporting the growth and stemness of BC cells.

circRNA RPPH1 Facilitates the Aggravation of Breast Cancer Development by Regulating miR-542-3p/ARHGAP1 Pathway

Background: Circular RNAs (circRNAs) have important roles in human malignancies, including breast cancer (BC). In this study, we intended to explore the function of circRNA ribonuclease P RNA component H1 (circ_RPPH1) in BC development and clarify the mechanistic pathway. Methods: Expression of circ_RPPH1, microRNA-542-3p (miR-542-3p), and Rho GTPase-activating protein 1 (ARHGAP1) in BC tissues and cells was determined by quantitative real-time polymerase chain reaction or Western blot assay. The stability of circ_RPPH1 was confirmed by RNase R and actinomycin D treatment. Cell viability and colony formation ability were measured by methyl thiazolyl tetrazolium (MTT) assay and colony formation assay, respectively. Western blot analysis was also used to detect proliferation biomarker (Ki67) and epithelial-mesenchymal transition (EMT) biomarkers (E-cadherin, N-cadherin, and vimentin). Flow cytometry and Transwell assays were performed to monitor cell apoptosis, migration, and invasion. The binding potency between miR-542-3p and circ_RPPH1 or ARHGAP1 was validated by dual-luciferase reporter assay. Functional role of circ_RPPH1 in vivo was investigated by xenograft tumor reporter assay. Results: Upregulation of circ_RPPH1 and ARHGAP1, and downregulation of miR-542-3p were detected in BC tissues and cells. circ_RPPH1 knockdown or miR-542-3p introduction inhibited BC cell proliferation and metastasis, while promoted apoptosis in vitro. circ_RPPH1 sponged miR-542-3p to upregulate ARHGAP1 expression, thereby affecting BC progression. Moreover, depletion of circ_RPPH1 suppressed tumor growth in vivo. Conclusions: circ_RPPH1 contributed to BC tumorigenesis by sponging miR-542-3p and upregulating ARHGAP1, affording a novel mechanistic pathway in BC development.

AC092127.1-miR-451a-AE binding protein 2 Signaling Facilitates Malignant Properties of Breast Cancer

Purpose

The purpose of the current study was to explore the functions and potential mechanism of miR-451a in breast cancer (BC).

Methods

Quantitative reverse transcription real-time polymerase chain reaction was used to analyze the expression of miR-451a in human normal mammary cells (MCF-10A) and BC cells. Colony formation assay, terminal-deoxynucleoitidyl transferase mediated nick end labeling assay and transwell assays were conducted to validate the effect of miR-451a on proliferation, apoptosis, migration and invasion of BC cells, respectively. RNA pull-down, RNA immunoprecipitation and luciferase reporter assays were applied to investigate the upstream and downstream mechanisms of miR-451a in BC cells.

Results

MiR-451a was expressed at a low level in BC cells. Overexpression of miR-451a repressed BC cells proliferation, migration and invasion. Moreover, long non-coding RNA AC092127.1 acted as a sponge of miR-451a to enhance the expression level of AE binding protein 2 (AEBP2) that was demonstrated to be the target gene of miR-451a in BC cells. Finally, rescue experiments validated that miR-451a and AEBP2 involved in AC092127.1-mediated BC cell growth, migration and invasion.

Conclusion

In a word, AC092127.1/miR-451a/AEBP2 axis contributes to BC cell growth, migration and invasion. Our results may help to find novel potential targets for BC treatment.

The Emerging Role of Circular RNAs in Alzheimer's Disease and Parkinson's Disease

Alzheimer’s disease (AD) and Parkinson’s disease (PD) are two neurodegenerative diseases (NDDs) commonly found in elderly patients that are difficult to diagnose and lack effective treatment. Currently, the available diagnostic methods for these two NDDs do not meet clinical diagnostic expectations. Circular RNAs (circRNAs) are a diverse group of endogenous non-coding RNAs (ncRNAs) found in eukaryotic cells. Emerging studies suggest that altered expression of circRNAs is involved in the pathological processes of NDDs. CircRNAs could also prove to be promising biomarkers for the early diagnosis of NDDs such as AD and PD. Growing evidence has improved our knowledge of the roles of circRNAs in NDDs, which may lead to new therapeutic approaches that target transcription for preventing neurodegeneration. In this review, we describe the formation mechanisms and functions of circRNAs as well as methods of validation. We also discuss the emerging role of circRNAs in the pathophysiology of AD and PD and their potential value as biomarkers and therapeutic targets for AD and PD in the future.

Prognostic Implications of microRNA-155, -133a, -21 and -205 in Breast Cancer Patients' Plasma

BACKGROUND

Breast cancer, being a heterogenous disease at the intra-tumoral and intertumoral levels, presents challenges in following the progress of the disease. Tumour-secreted aberrantly expressed miRNAs obtained from peripheral blood represent a non-invasive alternative resource for detecting and monitoring the development of the disease. This study evaluates the expression of miR-155, miR-133a, miR-21 and miR-205 as non-invasive, prognostic and follow-up markers for breast cancer.

METHODS

Plasma expression levels of miR-155, miR-133a, miR-21 and miR-205 were measured using real-time PCR in breast cancer patients (n=63) at presentation, healthy controls (n=25), and in post-treatment samples of 31 patients. A meta-analysis was performed using 43 studies identified from PubMed, Google Scholar and Scopus databases. Hedge's g values were used to calculate the overall effect size.

RESULTS

Plasma miR-21 levels were higher in breast cancer patients at presentation compared to controls, while no difference was observed for miR-155, miR-133a and miR-205. These results were further supported by the meta-analysis. The altered levels of miR-155 during tamoxifen treatment indicated a potential role for miR-155 in monitoring treatment response. Further, high expressions of at least three miRNAs correlated with poor overall survival in the breast cancer patients.

CONCLUSION

Plasma levels of miR-155, miR-133a, miR-21 and miR-205 may be useful as prognostic and follow-up markers for breast cancer with further validation in a large cohort of patients.

miR-328-3p, a Predictor of Stroke, Aggravates the Cerebral Ischemia-Reperfusion Injury

Background

In the present study, we aimed to identify microRNAs (miRNAs) that affected the prognosis of stroke and assess their biological effects.

Materials and Methods

A high-throughput sequencing (HTS) analysis was performed to screen distinctive miRNAs in serum exosomes of stroke patients, and these miRNAs were subsequently validated using individual quantitative real-time polymerase chain reaction (qRT-PCR) in a cohort consisting of 39 stroke patients and 20 normal controls. Briefly, miR-328-3p agomir or agomir NC was injected into rats before ischemia and reperfusion (I/R) injury. Zea-Longa score, neurological severity score (mNSS), triphenyltetrazolium chloride (TTC) staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, transmission electron microscopy, and hematoxylin and eosin (H&E) staining were used to examine the brain injury. Immunohistochemistry was utilized to determine the expressions of TNF-α and IL-6.

Results

The expression of serum exosomal miR-328-3p was significantly reduced in patients with an infarct volume ≥10 cm³ (P=0.01). Serum exosomal miR-328-3p was associated with the short-term prognosis (P=0.02), and the level of miR-328-3p was an independent relative factor for short-term prognosis (OR 5.276, P=0.02). The sensitivity of miR-328-3p level higher than 1.24 to predict the severity of the patient’s 1-week prognosis was 70%, and the specificity was 83% (AUC=0.74, P=0.02). The mNSS was higher in the miR-328-3p agomir group compared with the agomir NC group (P=0.03). Neutrophil infiltration was more serious in the miR-328-3p agomir group.

Conclusion

Our study indicated that miR-328-3p played a critical predictive role in the short-term prognosis of stroke, and up-regulation of miR-328-3p aggravated cerebral I/R injury.

Non-Coding RNAs Based Molecular Links in Type 2 Diabetes, Ischemic Stroke, and Vascular Dementia

This article reviews recent advances in the study of microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and their functions in type 2 diabetes mellitus (T2DM), ischemic stroke (IS), and vascular dementia (VaD). miRNAs and lncRNAs are gene regulation markers that both regulate translational aspects of a wide range of proteins and biological processes in healthy and disease states. Recent studies from our laboratory and others have revealed that miRNAs and lncRNAs expressed differently are potential therapeutic targets for neurological diseases, especially T2DM, IS, VaD, and Alzheimer's disease (AD). Currently, the effect of aging in T2DM, IS, and VaD and the cellular and molecular pathways are largely unknown. In this article, we highlight results from the works on the molecular connections between T2DM and IS, and IS and VaD. In each disease, we also summarize the pathophysiology and the differential expressions of miRNAs and lncRNAs. Based on current research findings, we hypothesize that 1) T2DM bi-directionally and age-dependently induces IS and VaD, and 2) these changes are precursors to the onset of dementia in elderly people. Research into these hypotheses is required to examine further whether research efforts on reducing T2DM, IS, and VaD may affect dementia and/or delay the AD disease process in the aged population.

miR-885-5p Inhibits Invasion and Metastasis in Gastric Cancer by Targeting Malic Enzyme 1

Several studies have reported that miR-885-5p was dysregulated in a variety of cancers. However, there are few studies on the biological function of miR-885-5p in gastric cancer (GC). In this study, we investigated the biological function and underlying mechanism of miR-885-5p in GC. Quantitative real-time PCR was used to examine the expression of miR-885-5p in GC. Bioinformatics analysis was used to predict the target of miR-885-5p and confirmed using the luciferase reporter assay. Wound-healing and Transwell assay were conducted to evaluate the biological function of miR-885-5p and malic enzyme 1 (ME1). Western blotting was used to assess molecular changes. Hepatic and lung metastasis models were constructed and used to verify the role of miR-885-5p. We found that the expression of miR-885-5p was significantly downregulated in GC. Overexpression of miR-885-5p inhibited invasion and metastasis of GC in vivo and in vitro, while inhibition of miR-885-5p has the opposite result in vitro. ME1 is a direct target of miR-885-5p, overexpressed in GC, associated with poor prognosis. Overexpression of miR-885-5p negatively regulates ME1 and causes changes in downstream molecules Vimentin and Fibronectin. Our research found that miR-885-5p plays a tumor suppressor gene and could potentially serve as a biomarker and therapeutic target in GC.

Early detection breast cancer: role of circulating plasma miRNA-21 expression as a potential screening biomarker

Aim

To explore the potential of the circulating plasma miRNA-21 as an early detection biomarker by comparing early-stage breast cancer (BG) and healthy control (HG) in Indonesian population.

Materials and methods

The enlisted patients were 26 adult female early-stage breast cancer patients (stage 1A, 1B, 2A, and 2B) of Airlangga University Hospital from August 2019 to October 2019. Sixteen volunteers were recruited as matching healthy subjects. MiRNA-21 expression was quantified by plasma qRT-PCR. Data analysis performed using IBM SPSS Statistics v.24 (IBM Corp., Armonk, NY, USA). MiRNA-21 cut-off, sensitivity, and specificity were analyzed using receiver operating characteristic (ROC) curve.

Results

The study included 26 BG and 16 HG subjects. The miRNA-21 expression in BG group was 3.933 (1.181-11.794) and 0.905 (0.164-4.532) in HG group (4.34 folds; P = 0.001), with 1.66 cut-off (92.3% sensitivity; 81.2% specificity). MiRNA-21 expression separated analysis in HG showed a 0.578 times lower expression in menopause subjects [0.651 (0.164-0.414)], compared to premenopause ones [(1.123 (0.758 - 4.532); P = 0.031]. Yet, in BG group, 1.729 times higher miRNA-21 expression was observed in menopause subjects (6.021 ± 3.583), compared to premenopause ones (3.500 ± 1.517; P = 0.022).

Conclusions

Circulating miRNA-21 expression is a potential biomarker for early detection of breast cancer and might act as a breast cancer risk predictor.

miRNAs: Critical mediators of breast cancer metastatic programming

MicroRNA mediated aberrant gene regulation has been implicated in several diseases including cancer. Recent research has highlighted the role of epigenetic modulation of the complex process of breast cancer metastasis by miRNAs. miRNAs play a crucial role in the process of metastatic evolution by facilitating alterations in the phenotype of tumor cells and the tumor microenvironment that promote this process. They act as critical determinants of the multi-step progression starting from carcinogenesis all the way to organotropism. In this review, we focus on the current understanding of the compelling role of miRNAs in breast cancer metastasis.

Urinary Exosomal MicroRNAs as Potential Non-invasive Biomarkers in Breast Cancer Detection

INTRODUCTION

Breast cancer (BC) is the most frequent malignant disease in women worldwide and is therefore challenging for the healthcare system. Early BC detection remains a leading factor that improves overall outcome and disease management. Aside from established screening procedures, there is a constant demand for additional BC detection methods. Routine BC screening via non-invasive liquid biopsy biomarkers is one auspicious approach to either complete or even replace the current state-of-the-art diagnostics. The study explores the diagnostic potential of urinary exosomal microRNAs with specific BC biomarker characteristics to initiate the potential prospective application of non-invasive BC screening as routine practice.

METHODS

Based on a case-control study (69 BC vs. 40 healthy controls), expression level quantification and subsequent biostatistical computation of 13 urine-derived microRNAs were performed to evaluate their diagnostic relevance in BC.

RESULTS

Multilateral statistical assessment determined and repeatedly confirmed a specific panel of four urinary microRNA types (miR-424, miR-423, miR-660, and let7-i) as a highly specific combinatory biomarker tool discriminating BC patients from healthy controls, with 98.6% sensitivity and 100% specificity.

DISCUSSION

Urine-based BC diagnosis may be achieved through the analysis of distinct microRNA panels with proven biomarker abilities. Subject to further validation, the implementation of urinary BC detection in routine screening offers a promising non-invasive alternative in women's healthcare.

miR-let-7a-5p Inhibits Invasion and Migration of Hepatoma Cells by Regulating BZW2 Expression

Purpose

This study was performed to investigate the effect of miRNA let-7a-5p on the proliferation, invasion, and migration of human hepatoma cells as well as to determine BZW2 expression in these cells.

Methods

Western blotting and real-time quantitative polymerase chain reaction were used to detect changes in the expression of miRNA let-7a-5p and BZW2 protein and gene, respectively. A luciferase reporter gene assay was used to examine whether BZW2 is the target gene of miR-let-7a-5p. The effect of miR-let-7a-5p on the invasion, migration, and proliferation of human hepatoma Bel-7404 and HepG2 cells was determined using the transwell invasion assay, scratch test, and CCK-8 assay, respectively. Flow cytometry was used to assess the effect of miR-let-7a-5p and BZW2 expression on apoptosis of hepatoma cells.

Results

The luciferase reporter gene assay identified BZW2 as the target gene of miR-let-7a-5p. Moreover, increased expression of miR-let-7a-5p was found to significantly decrease BZW2 expression; inhibit proliferation, invasion, and migration; and promote apoptosis of hepatoma cells.

Conclusion

miR-let-7a-5p can inhibit proliferation, invasion, and migration as well as promote apoptosis of hepatoma cells by decreasing BZW2 expression.

ZLM-7 inhibits the occurrence and angiogenesis of breast cancer through miR-212-3p/Sp1/VEGFA signal axis

Background

Breast cancer (BC) is a common malignant tumor with poor prognosis. Angiogenesis is related to the growth and progression of solid tumors and associated with prognosis. ZLM-7, SP1, VEGFA and miR-212-3p were associated with BC angiogenesis and proliferation, however the detailed mechanism was not clear. This study aimed to reveal the regulatory mechanism of angiogenesis of BC.

Methods

BC cell lines were treated with 10 nM ZLM-7 for 8 h. We detected protein expression level by western blot and RNA expression level by qRT-PCR. Overexpression or inhibition of miR-212-3p is performed using miR-212-3p mimics or miR-212-3p inhibitor, Sp1 overexpression using pcDNA3.1 vector. Angiogenesis was analyzed by co-culturing BC cell lines and HUVEC cells. To evaluate regulatory relationship between miR-212-3p and Sp1, dual luciferase assay was performed. Besides, the direct interaction between Sp1 and VEGFA was analyzed by ChIP. Migration and invasion were analyzed by transwell assay and proliferation was detected by clone formation assay. In mice xenograft model developed using BC cells, we also detected angiogenesis marker CD31 through immunohistochemistry.

Results

ZLM-7 up-regulated miR-212-3p and inhibited invasion, migration, proliferation and angiogenesis of BC, while miR-212-3p inhibitor antagonized such effects. Binding sequence was revealed between miR-212-3p and Sp1, and expression of Sp1 was inhibited by miR-212-3p on both protein and mRNA level. Sp1 could interact with VEGFA and promoted its expression. Overexpression of miR-212-3p inhibited migration, invasion, proliferation and angiogenesis of BC cell lines, while Sp1 overexpression showed the opposite effect and could antagonize these effects of miR-212-3p overexpression. ZLM-7 decreased VEGFA expression, which was rescued by co-transfection with miR-212-3p inhibitor. Similar, ZLM-7 could inhibit tumor growth and angiogenesis through the miR-212-3p/Sp1/VEGFA axis in vivo.

Conclusions

ZLM-7 could directly up-regulate miR-212-3p in BC. MiR-212-3p could inhibit VEGFA expression through Sp1, thereby inhibiting angiogenesis and progression of BC.

Knockdown of CircCRIM1 Inhibits HDAC4 to Impede Osteosarcoma Proliferation, Migration, and Invasion and Facilitate Autophagy by Targeting miR-432-5p

BACKGROUND

Circular RNAs (circRNAs) serve for a genre of considerable modulatory molecules that have been largely researched in human cancers. However, the contribution of circRNA cysteine-rich transmembrane bone morphogenetic protein regulator 1 (circCRIM1) to osteosarcoma (OS) is completely unclear.

METHODS

All the RNA levels were examined via quantitative real-time polymerase chain reaction (qRT-PCR). Cellular proliferation and migration/invasion were, respectively, analyzed using 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) assay and transwell assay. The determination of all protein expression was administrated by Western blot. Dual-luciferase reporter assay was used for proving the target combination. The exploration of circCRIM1 in vivo was performed by xenograft assay.

RESULTS

In OS tissues and cells, circCRIM1 was differentially up-regulated. Functionally, cell proliferation, migration and invasion were suppressed while autophagy was promoted after circCRIM1 was down-regulated in OS cells. Mechanistically, mircoRNA-432-5p (miR-432-5p) was a miRNA target of circCRIM1 and the inhibitory effect of circCRIM1 knockdown on OS progression was achieved by targeting miR-432-5p. Moreover, histone deacetylase 4 (HDAC4) was a downstream gene of miR-432-5p and circCRIM1 targeted miR-432-5p to up-regulate HDAC4 level. MiR-432-5p inhibited proliferation, migration, and invasion but enhanced autophagy of OS cells through down-regulating HDAC4. In vivo, knockdown of circCRIM1 decreased OS growth via acting on the miR-432-5p/HDAC4 axis.

CONCLUSION

Our findings elucidated the oncogenic function of circCRIM1 in OS via the regulation of the miR-432-5p/HDAC4 axis, affording a novel view about how circRNA participated in OS development.

Liquid biopsy for breast cancer using extracellular vesicles and cell-free microRNAs as biomarkers

Improvement of breast cancer (BC) patient's outcome is directly related to early detection. However, there is still a lack of reliable biomarkers for diagnosis, prognosis and, treatment follow up in BC, leading researchers to study the potential of liquid biopsy based on circulating microRNAs (c-miRNAs). These c-miRNAs can be cell-free or associated with extracellular vesicles (EVs), and have great advantages such as stability in biofluids, noninvasive accessibility compared to current techniques (core-biopsy and surgery), and expression associated with pathogenic conditions. Recently, a new promising field of EV-derived miRNAs (EV-miRNAs) as cancer biomarkers has emerged, receiving special attention due to their selective vesicle sorting which makes them accurate for disease detection. In this review, we discuss new findings about c-miRNA and their potential as biomarkers for BC diagnosis, prognosis, and therapy. Additionally, we address the impact of limitations associated with the standardization of analysis techniques and methods on the implementation of these biomarkers in the clinical setting.

CircFAT1 Suppresses Colorectal Cancer Development Through Regulating miR-520b/UHRF1 Axis or miR-302c-3p/UHRF1 Axis

Background: It was reported that circular RNAs (circRNAs) exerted important functions in various human cancers. However, the function of circFAT1 was less known. The purpose of this study was to reveal the functional mechanism of circFAT1 in colorectal cancer (CRC). Materials and Methods: Quantitative real-time polymerase chain reaction and Western blot assay were used to detect the levels of genes. Cell proliferation ability was assessed by 3-(4, 5-dimethyl-2-thiazoyl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was used to investigate cell apoptosis rate. The glucose consumption and lactate production were determined using related kits. Furthermore, the interaction between circFAT1 or ubiquitin-like PHD and RING finger domain-containing protein 1 (UHRF1) and miR-520b or miR-302c-3p was predicted by starbase3.0, and then confirmed by the dual-luciferase reporter assay. Besides, xenograft experiment was performed to analyze the effect of circFAT1 on tumor growth in vivo. Results: The levels of circFAT1 and UHRF1 were increased, as well as the levels of miR-520b and miR-302c-3p were decreased in CRC tissues and cells. CircFAT1 knockdown suppressed cell proliferation, cycle, and glycolysis as well as induced apoptosis. Interestingly, circFAT1 was a sponge of miR-520b and miR-302c-3p, and miR-520b and miR-302c-3p could target UHRF1. Both miR-520b overexpression and miR-302c-3p overexpression inhibited CRC cell growth. Furthermore, both miR-520b knockdown and miR-302c-3p depletion weakened the effect of circFAT1 knockdown on the growth of CRC cells. Besides, circFAT1 depletion repressed tumor growth in vivo. Conclusion: The authors' findings suggested that circFAT1 upregulated UHRF1 to affect CRC cell proliferation, apoptosis, and glycolysis through targeting miR-520b and miR-302c-3p, providing theoretical basis for the treatment of CRC.

Prognostic role of microRNAs in breast cancer: A systematic review

MicroRNAs (miRNAs) have been found to play an important role in breast cancer, functioning either as potential oncogenes or tumor suppressor genes, but their role in the prognosis of patients remains unclear. The aim of the present review study is to highlight recent preclinical and clinical studies performed on both circulating and tissue-specific miRNAs and their potential role as prognostic markers in breast cancer. We systematically searched the PubMed database to explore the prognostic value of miRNAs in breast cancer. After performing the literature search and review, 117 eligible studies were identified. We found that 110 aberrantly expressed miRNAs have been associated with prognosis in breast cancer. In conclusion, the collective data presented in this review indicate that miRNAs could serve as novel prognostic tools in breast cancer, while the clinical application of these findings has yet to be verified.

Circulating miRNAs as Diagnostic and Prognostic Biomarkers in Common Solid Tumors: Focus on Lung, Breast, Prostate Cancers, and Osteosarcoma

An early cancer diagnosis is essential to treat and manage patients, but it is difficult to achieve this goal due to the still too low specificity and sensitivity of classical methods (imaging, actual biomarkers), together with the high invasiveness of tissue biopsies. The discovery of novel, reliable, and easily collectable cancer markers is a topic of interest, with human biofluids, especially blood, as important sources of minimal invasive biomarkers such as circulating microRNAs (miRNAs), the most promising. MiRNAs are small non-coding RNAs and known epigenetic modulators of gene expression, with specific roles in cancer development/progression, which are next to be implemented in the clinical routine as biomarkers for early diagnosis and the efficient monitoring of tumor progression and treatment response. Unfortunately, several issues regarding their validation process are still to be resolved. In this review, updated findings specifically focused on the clinical relevance of circulating miRNAs as prognostic and diagnostic biomarkers for the most prevalent cancer types (breast, lung, and prostate cancers in adults, and osteosarcoma in children) are described. In addition, deep analysis of pre-analytical, analytical, and post-analytical issues still affecting the circulation of miRNAs' validation process and routine implementation is included.

Surveillance of Tumour Development: The Relationship Between Tumour-Associated RNAs and Ribonucleases

Tumour progression is accompanied by rapid cell proliferation, loss of differentiation, the reprogramming of energy metabolism, loss of adhesion, escape of immune surveillance, induction of angiogenesis, and metastasis. Both coding and regulatory RNAs expressed by tumour cells and circulating in the blood are involved in all stages of tumour progression. Among the important tumour-associated RNAs are intracellular coding RNAs that determine the routes of metabolic pathways, cell cycle control, angiogenesis, adhesion, apoptosis and pathways responsible for transformation, and intracellular and extracellular non-coding RNAs involved in regulation of the expression of their proto-oncogenic and oncosuppressing mRNAs. Considering the diversity/variability of biological functions of RNAs, it becomes evident that extracellular RNAs represent important regulators of cell-to-cell communication and intracellular cascades that maintain cell proliferation and differentiation. In connection with the elucidation of such an important role for RNA, a surge in interest in RNA-degrading enzymes has increased. Natural ribonucleases (RNases) participate in various cellular processes including miRNA biogenesis, RNA decay and degradation that has determined their principal role in the sustention of RNA homeostasis in cells. Findings were obtained on the contribution of some endogenous ribonucleases in the maintenance of normal cell RNA homeostasis, which thus prevents cell transformation. These findings directed attention to exogenous ribonucleases as tools to compensate for the malfunction of endogenous ones. Recently a number of proteins with ribonuclease activity were discovered whose intracellular function remains unknown. Thus, the comprehensive investigation of physiological roles of RNases is still required. In this review we focused on the control mechanisms of cell transformation by endogenous ribonucleases, and the possibility of replacing malfunctioning enzymes with exogenous ones.

MicroRNA regulation in colorectal cancer tissue and serum

Colorectal cancer is recognized as the fourth leading cause of cancer-related deaths worldwide. Thus, there is ongoing search for potential new biomarkers allowing quicker and less invasive detection of the disease and prediction of the treatment outcome. Therefore, the aim of our study was to identify colorectal cancer specific miRNAs expressed in cancerous and healthy tissue from the same patient and to further correlate the presence of the same miRNAs in the circulation as potential biomarkers for diagnosis. In the current study we detected a set of 40 miRNAs differentially regulated in tumor tissue when comparing with healthy tissue. Additionally, we found 8 miRNAs differentially regulated in serum of colorectal cancer patients. Interestingly, there was no overlap in miRNAs regulated in tissue and serum, suggesting that serum regulated miRNAs may be not actively secreted from colorectal tumor cells. However, four of differentially expressed miRNAs, including miR-21, miR-17, miR-20a and miR-32 represent the miRNAs characteristic for different tumor types, including breast, colon, lung, pancreas, prostate and stomach cancer. This finding suggests important groups of miRNAs which can be further validated as markers for diagnosis of tumor tissue and regulation of carcinogenesis.

Decoding the Role of Platelets and Related MicroRNAs in Aging and Neurodegenerative Disorders

Platelets are anucleate cells that circulate in blood and are essential components of the hemostatic system. During aging, platelet numbers decrease and their aggregation capacity is reduced. Platelet dysfunctions associated with aging can be linked to molecular alterations affecting several cellular systems that include cytoskeleton rearrangements, signal transduction, vesicular trafficking, and protein degradation. Age platelets may adopt a phenotype characterized by robust secretion of extracellular vesicles that could in turn account for about 70-90% of blood circulating vesicles. Interestingly these extracellular vesicles are loaded with messenger RNAs and microRNAs that may have a profound impact on protein physiology at the systems level. Age platelet dysfunction is also associated with accumulation of reactive oxygen species. Thereby understanding the mechanisms of aging in platelets as well as their age-dependent dysfunctions may be of interest when evaluating the contribution of aging to the onset of age-dependent pathologies, such as those affecting the nervous system. In this review we summarize the findings that link platelet dysfunctions to neurodegenerative diseases including Alzheimer's Disease, Parkinson's Disease, Multiple Sclerosis, Huntington's Disease, and Amyotrophic Lateral Sclerosis. We discuss the role of platelets as drivers of protein dysfunctions observed in these pathologies, their association with aging and the potential clinical significance of platelets, and related miRNAs, as peripheral biomarkers for diagnosis and prognosis of neurodegenerative diseases.

microRNA and Other Small RNA Sequence Profiling across Six Tissues of Chinese Forest Musk Deer (Moschus berezovskii)

The Chinese forest musk deer (Moschus berezovskii) is an economically important species distributed throughout southwest China and northern Vietnam. Occurrence and development of disease are aggravated by inbreeding and genetic diversity declines in captive musk deer populations. Deep transcriptomics investigation may provide a promising way to improve genetic health of captive and wild FMD population. MicroRNAs (miRNAs), which regulate gene expression by targeting and suppressing of mRNAs, play an important role in physiology and organism development control. In this study, RNA-seq technology was adopted to characterize the miRNA transcriptome signature among six tissues (heart, liver, spleen, lung, kidney, and muscle) in Chinese forest musk deer at two years of age. Deep sequencing generated a total of 103,261,451 (~87.87%) good quality small RNA reads; of them 6,622,520 were unique across all six tissues. A total of 2890 miRNAs were identified, among them 1129 were found to be expressed in all tissues. Moreover, coexpression of 20 miRNAs (>2000RPM) in all six tissues and top five highly expressed miRNAs in each tissue implied the crucial and particular function of them in FMD physiological processes. Our findings of forest musk deer miRNAs supplement the database of transcriptome information for this species and conduce to our understanding of forest musk deer biology.

Overexpression and mutation of ZNF384 is associated with favorable prognosis in breast cancer patients

Background

To search for genes with high sensitivity and to explore its application value related to clinical prognostic prediction, so as to provide important foundation for the preventive intervention, early diagnosis, treatment and prognosis evaluation for breast cancer.

Methods

Tissue samples from ten clinical breast cancer patients were collected to search for the common mutant genes among various samples, and to explore the enrichment degree of mutant genes at both disease and signaling pathway levels using the whole exome sequencing (WES). Subsequently, targets genes with changes in expression levels that showed high correlations with mutation were screened from the above common genes using The Cancer Genome Atlas (TCGA) database. On this basis, differences in the mutation and expression levels of the screened target genes between breast cancer tissues and para-carcinoma tissues, as well as their correlations with patient survival were analyzed using the gene expression and mutation data in TCGA database, together with the clinical information. Finally, the potential regulatory pathways and potential downstream targets of the target genes were predicted through gene set enrichment analysis (GSEA) using Multi-Experiment Matrix (MEM) software.

Results

A total of 23 common mutant genes were discovered from the tissue samples from ten breast cancer patients, which were mostly enriched in the cancer, PI3K/Akt and cAMP signaling pathways. Among these 23 genes, only the changes in the expression levels of ZNF384 and PDE4DIP had displayed over 15% consistency with mutation. Besides, it was discovered through TCGA database analysis that, the expression level of ZNF384 gene in breast cancer tissues with ZNF384 mutation was far higher than that in those with no ZNF384 mutation. Moreover, such gene mutation and high expression had shown significantly positive correlation with the patient survival (P<0.05). In addition, GSEA indicated that, tissues with high ZNF384 expression were associated with enrichments related to cell cycle signaling pathway and mitosis metaphase pathway, while this series of effects might be correlated with its regulation on the level and activity of its downstream gene CXCL14.

Conclusions

ZNF384 mutation and up-regulated ZNF384 expression level in breast cancer tissues is significantly positively correlated with patient survival. Therefore, ZNF384 can serve as a molecular marker for the diagnosis and prognostic prediction of breast cancer as well as a potential therapeutic target.

Serum miRNAs Expression and SNAP-25 Genotype in Alzheimer's Disease

MicroRNAs (miRNAs) are small non-coding RNAs that control gene expression by binding their 3' untranslated region (3'UTR) region; these molecules play a fundamental role in several pathologies, including Alzheimer's disease (AD). Synaptosomal-associated protein of 25 kDa (SNAP-25) is a vesicular protein of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) involved in neural plasticity and in the exocytosis of neurotransmitters, processes that are altered in AD. Recent results showed that a reduction of SNAP-25 is associated with dementia, and that the rs363050 SNAP-25 polymorphism correlates with cognitive decline and brain atrophy, as well as with the outcome of multistructured rehabilitation in AD patients. We verified the presence of possible correlations between the serum concentration of miRNAs that bind the SNAP-25 3'UTR region and AD. Six different microRNAs (miR-181a-5p, miR-361-3p, miR-23a-3p, miR-15b-3p, 130a-3p and miR-27b-3p) that bind the SNAP-25 3'UTR region were measured by qPCR in serum of AD patients (n = 22), mild cognitive impairment (MCI) subjects (n = 22) and age- and sex-matched controls (n = 22); analysis of results was done stratified for the rs363050 SNAP-25 genotype. Results showed that miR-27b-3p, miR-23a-3p and miR181a-5p serum concentration was significantly reduced in rs363050 SNAP-25 GG homozygous AD patients. Notably, concentration of these miRNAs was comparable in rs363050 AA homozygous AD patients, MCI and healthy controls (HCs). Data herein suggest that miRNAs that bind the SNAP-25 3'UTR region interact with SNAP-25 polymorphisms to influence the neural plasticity typical of AD brains, possibly as a consequence of modulatory activity on SNAP-25 mRNA and/or protein.