Elevated levels of miR-210 correlate with anemia in β-thalassemia/HbE patients

Clinical implications of miRNAs in erythropoiesis, anemia, and other hematological disorders

Erythropoiesis is regulated by the differential expression of many genes. Besides being transcriptionally regulated, these genes are also with the oath of epigenetic regulation by the microRNAs (miRNAs), in particular. Various miRNAs appear to be very important for the normal process of erythropoiesis and various hematological abnormalities in humans. Therefore, the review aims to summarize the significance of miRNAs in erythropoiesis and different hematological diseases with clinical importance. Our analysis indicates that specific miRNAs regulate erythropoiesis in a stage-specific manner from hematopoietic stem cells to differentiated erythrocytes. Further, many miRNAs have been reported to be linked with various hematological diseases. The importance of miRNAs as biomarkers or therapeutic drug targets for various hematological disorders like anemia, β-thalassemia, and leukemia has been revealed through various clinical studies and clinical trials. The miR-34a mimic and miR-155 inhibitor demonstrate promising therapeutic effects in various hematological malignancies. Additionally, miR-34a, miR-538e, miR-193e, and miR-198 exhibit diagnostic potential in acute myeloid leukemia, while miR-451, miR-151-5p, and miR-1290 show diagnostic potential in B-cell acute lymphoblastic leukemia. Thus, this review encompasses the latest observations and implications of specific miRNAs in erythropoiesis and various hematological disorders. However, challenges persist in developing safe and efficient delivery strategies to target miRNAs specifically, minimizing off-target effects and enhancing therapeutic outcomes. Future mechanistic pre-clinical and clinical research would contribute to overcoming these challenges.

Expression of microRNA-155 in thalassemic erythropoiesis

Background

Ineffective erythropoiesis (IE) is the primary cause of anemia and associated pathologies in β-thalassemia. The characterization of IE is imbalance of erythroid proliferation and differentiation, resulting in increased erythroblast proliferation that fails to differentiate and gives rise to enucleate RBCs. MicroRNAs (miRs) are known to play important roles in hematopoiesis. miR-155 is a multifunctional molecule involved in both normal and pathological hematopoiesis, and its upregulation is observed in patients with β-thalassemia/HbE. However, the expression and function of miR-155, especially in β-thalassemia, have not yet been explored.

Methods

To study miR-155 expression in thalassemia, erythroblast subpopulations, CD45-CD71+Ter-119+ and CD45-CD71-Ter-119+ were collected from β IVSII-654 thalassemic bone marrow. Additionally, a two-phase culture of mouse bone marrow erythroid progenitor cells was performed. Expression of miR-155 and predicted mRNA target genes, c-myc, bach-1 and pu-1, were determined by quantitative reverse transcription (qRT)-polymerase chain reaction (PCR) and normalized to small nucleolar RNA (snoRNA) 202 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), respectively. To investigate the effect of miR-155 expression, erythroblasts were transfected with miR-inhibitor and -mimic in order to elevate and eliminate miR-155 expression, respectively. Erythroid cell differentiation was evaluated by Wright-Giemsa staining and flow cytometry.

Results

miR-155 was upregulated, both in vivo and in vitro, during erythropoiesis in β-thalassemic mice. Our study revealed that gain- and loss of function of miR-155 were involved in erythroid proliferation and differentiation, and augmented proliferation and differentiation of thalassemic mouse erythroblasts may be associated with miR-155 upregulation. miR-155 upregulation in β-thalassemic mice significantly increased the percentage of basophilic and polychromatic erythroblasts. Conversely, a significant decrease in percentage of basophilic and polychromatic erythroblasts was observed in β-thalassemic mice transfected with anti-miR-155 inhibitor. We also examined the mRNA targets (c-myc, bach-1 and pu-1) of miR-155, which indicated that c-myc is a valid target gene of miR-155 that regulates erythroid differentiation.

Conclusion

miR-155 regulates IE in β-thalassemia via c-myc expression controlling erythroblast proliferation and differentiation.

Metabolite and protein shifts in mature erythrocyte under hypoxia

As the only cell type responsible for oxygen delivery, erythrocytes play a crucial role in supplying oxygen to hypoxic tissues, ensuring their normal functions. Hypoxia commonly occurs under physiological or pathological conditions, and understanding how erythrocytes adapt to hypoxia is fundamental for exploring the mechanisms of hypoxic diseases. Additionally, investigating acute and chronic mountain sickness caused by plateaus, which are naturally hypoxic environments, will aid in the study of hypoxic diseases. In recent years, increasingly developed proteomics and metabolomics technologies have become powerful tools for studying mature enucleated erythrocytes, which has significantly contributed to clarifying how hypoxia affects erythrocytes. The aim of this article is to summarize the composition of the cytoskeleton and cytoplasmic proteins of hypoxia-altered erythrocytes and explore the impact of hypoxia on their essential functions. Furthermore, we discuss the role of microRNAs in the adaptation of erythrocytes to hypoxia, providing new perspectives on hypoxia-related diseases.

Enzyme-free sensitive SERS biosensor for the detection of thalassemia-associated microRNA-210 using a cascade dual-signal amplification strategy

BACKGROUND

β-thalassemia is a blood disorder caused by autosomal mutations. Gene modulation therapy to activate the γ-globin gene to induce fetal hemoglobin (HbF) synthesis has become a new option for the treatment of β-thalassemia. MicroRNA-210 (miR-210) contributes to studying the mechanism regulating γ-globin gene expression and is a potential biomarker for rapid β-thalassemia screening. Traditional miRNA detection methods perform well but necessitate complex and time-consuming miRNA sample processing. Therefore, the development of a sensitive, accurate, and simple miRNA level monitoring method is essential.

RESULTS

We have developed a non-enzymatic surface-enhanced Raman scattering (SERS) biosensor utilizing a signal cascade amplification of catalytic hairpin assembly reaction (CHA) and proximity hybridization-induced hybridization chain reaction (HCR). Au@Ag NPs were used as the SERS substrate, and methylene blue (MB)- modified DNA hairpins were used as the SERS tags. The SERS assay involved two stages: implementing the CHA-HCR cascade signal amplification strategy and conducting SERS measurements on the resulting product. The HCR was started by the products of target-triggered CHA, which formed lengthy nicked double-stranded DNA (dsDNA) on the Au@Ag NPs surface to which numerous SERS tags were attached, leading to a significant increase in the SERS signal intensity. High specificity and sensitivity for miR-210 detection was achieved by monitoring MB SERS intensity changes. The suggested SERS biosensor has a low detection limit of 5.13 fM and is capable of detecting miR-210 at concentration between 10 fM and 1.0 nM.

SIGNIFICANCE

The biosensor can detect miR-210 levels in the erythrocytes of β-thalassemia patients, enabling rapid screening for β-thalassemia and suggesting a novel approach for investigating the regulation mechanism of miR-210 on γ-globin gene expression. In the meantime, this innovative technique has the potential to detect additional miRNAs and to become an important tool for the early diagnosis of diseases and for biomedical research.

Impact of Hypoxia-Induced miR-210 on Pancreatic Cancer

Pancreatic cancer (PC) poses significant clinical challenges, with late-stage diagnosis and limited therapeutic options contributing to its dismal prognosis. A hallmark feature of PC is the presence of a profoundly hypoxic tumour microenvironment, resulting from various factors such as fibrotic stroma, rapid tumour cell proliferation, and poor vascularization. Hypoxia plays a crucial role in promoting aggressive cancer behaviour, therapeutic resistance, and immunosuppression. Previous studies have explored the molecular mechanisms behind hypoxia-induced changes in PC, focusing on the role of hypoxia-inducible factors (HIFs). Among the myriad of molecules affected by hypoxia, microRNA-210 (miR-210) emerges as a central player. It is highly responsive to hypoxia and regulated by HIF-dependent and HIF-independent pathways. miR-210 influences critical cellular processes, including angiogenesis, metastasis, and apoptosis, all of which contribute to PC progression and resistance to treatment. Understanding these pathways provides insights into potential therapeutic targets. Furthermore, investigating the role of miR-210 and its regulation in hypoxia sheds light on the potential development of early diagnostic strategies, which are urgently needed to improve outcomes for PC patients. This review delves into the complexities of PC and introduces the roles of hypoxia and miR-210 in the progression of PC.

Up-regulation of microRNA 101-3p during erythropoiesis in β-thalassemia/HbE

Ineffective erythropoiesis is the main cause of anemia in β-thalassemia. The crucial hallmark of ineffective erythropoiesis is the high proliferation of erythroblast. microRNA (miR/miRNA) involves several biological processes, including cell proliferation and erythropoiesis. miR-101 was widely studied and associated with proliferation in several types of cancer. However, the miR-101-3p has not been studied in β-thalassemia/HbE. Therefore, this study aims to investigate the expression of miR-101-3p during erythropoiesis in β-thalassemia/HbE. The results showed that miR-101-3p was upregulated in the erythroblast of β-thalassemia/HbE patients on day 7, indicating that miR-101-3p may be involved with high proliferation in β-thalassemia/HbE. Therefore, the mRNA targets of miR-101-3p including Rac1, SUB1, TET2, and TRIM44 were investigated to determine the mechanisms involved with high proliferation of β-thalassemia/HbE erythroblasts. Rac1 expression was significantly reduced at day 11 in severe β-thalassemia/HbE compared to normal controls and mild β-thalassemia/HbE. SUB1 gene expression was significantly lower in severe β-thalassemia/HbE compared to normal controls at day 9 of culture. For TET2 and TRIM44 expression, a significant difference was not observed among normal and β-thalassemia/HbE. However, the high expression of miR-101-3p at day 7 and these target genes was not correlated, suggesting that this miRNA may regulate ineffective erythropoiesis in β-thalassemia/HbE via other target genes.

Continuous Glucose Monitoring in Hypoxic Environments Based on Water Splitting-Assisted Electrocatalysis

Conventional enzyme-based continuous glucose sensors in interstitial fluid usually rely on dissolved oxygen as the electron-transfer mediator to bring electrons from oxidase to electrode while generating hydrogen peroxide. This may lead to several problems. First, the sensor may provide biased detection results owing to fluctuation of oxygen in interstitial fluid. Second, the polymer coatings that regulate the glucose/oxygen ratio can affect the dynamic response of the sensor. Third, the glucose oxidation reaction continuously produces corrosive hydrogen peroxide, which may compromise the long-term stability of the sensor. Here, we introduce an oxygen-independent nonenzymatic glucose sensor based on water splitting-assisted electrocatalysis for continuous glucose monitoring. For the water splitting reaction (i.e., hydrogen evolution reaction), a negative pretreatment potential is applied to produce a localized alkaline condition at the surface of the working electrode for subsequent nonenzymatic electrocatalytic oxidation of glucose. The reaction process does not require the participation of oxygen; therefore, the problems caused by oxygen can be avoided. The nonenzymatic sensor exhibits acceptable sensitivity, reliability, and biocompatibility for continuous glucose monitoring in hypoxic environments, as shown by the in vitro and in vivo measurements. Therefore, we believe that it is a promising technique for continuous glucose monitoring, especially for clinically hypoxic patients.

Non-coding RNAs in human health and disease: potential function as biomarkers and therapeutic targets

Human diseases have been a critical threat from the beginning of human history. Knowing the origin, course of action and treatment of any disease state is essential. A microscopic approach to the molecular field is a more coherent and accurate way to explore the mechanism, progression, and therapy with the introduction and evolution of technology than a macroscopic approach. Non-coding RNAs (ncRNAs) play increasingly important roles in detecting, developing, and treating all abnormalities related to physiology, pathology, genetics, epigenetics, cancer, and developmental diseases. Noncoding RNAs are becoming increasingly crucial as powerful, multipurpose regulators of all biological processes. Parallel to this, a rising amount of scientific information has revealed links between abnormal noncoding RNA expression and human disorders. Numerous non-coding transcripts with unknown functions have been found in addition to advancements in RNA-sequencing methods. Non-coding linear RNAs come in a variety of forms, including circular RNAs with a continuous closed loop (circRNA), long non-coding RNAs (lncRNA), and microRNAs (miRNA). This comprises specific information on their biogenesis, mode of action, physiological function, and significance concerning disease (such as cancer or cardiovascular diseases and others). This study review focuses on non-coding RNA as specific biomarkers and novel therapeutic targets.

Role of microRNA in hydroxyurea mediated HbF induction in sickle cell anaemia patients

Hydroxyurea (HU) is found to be beneficial in sickle cell anaemia (SCA) patients, due to its ability to increase foetal haemoglobin (HbF), however, patients show a variable response. Differences in HbF levels are attributed to many factors; but, the role of miRNA in HbF regulation is sparsely investigated. In this study, we evaluated the effect of miRNA expression on HbF induction in relation to hydroxyurea therapy in 30 normal controls, 30 SCA patients at baseline, 20 patients after 3 and 6 months of hydroxyurea (HU) therapy. HbF levels were measured by HPLC. Total RNA and miRNA were extracted from CD71⁺ erythroid cells and the expression was determined using Taqman probes. The mean HbF level increased 7.54 ± 2.44 fold, after 3 months of HU therapy. After the HU therapy 8 miRNAs were significantly up-regulated while 2 were down-regulated. The increase in miR-210, miR16-1, and miR-29a expression and decrease in miR-96 expression were strongly associated with the HU mediated HbF induction. Post HU therapy, decreased miR-96 expression negatively correlate with HbF and γ-globin gene while increased expression of miR-210, miR-16-1 and miR-29a post HU therapy positively corelate with HbF and γ-globin gene. Thus, suggest that miR-210, miR-16-1 and miR-29a are positive regulator of γ-globin gene and miR-96 is negative regulator of γ-globin gene. The study suggests the role of miR-210, miR16-1, miR-29a, and miR-96 in γ-globin gene regulation leading to HbF induction. Identification of the relevant protein targets might be useful for understanding the HU mediated HbF induction.

A review on the role of miR-210 in human disorders

MicroRNA-210 (miR-210) is a miRNA with imperative effects in the pathophysiology of human disorders. miR-210 is encoded by MIR210 gene on chromosome 11p15.5. The stem-loop of this miRNA resides in an intron of the AK123483 noncoding RNA. This miRNA is a major hypoxamir whose expression is increased in hypoxic condition in several types of cells. miR-210 has been shown to be up-regulated in almost all types of examined cancer types, except for bladder cancer, angiosarcoma and glioblastoma. Dysregulation of miR-210 in colorectal carcinoma, gastric cancer, head and neck squamous cell carcinoma, pediatric acute lymphoblastic leukemia, glioblastoma and laryngeal carcinoma has been related with poor clinical outcomes. In the current review, we provide a comprehensive summary of participation of miR-210 in human disorders.

Whole Blood miR-210, miR-122, miR-223 Expression Levels and Their Relationship With Iron Status Parameters and Hypercoagulability Indices in Children With Iron Deficiency Anemia

MicroRNAs have the potential to regulate systemic and cellular iron homeostasis at multiple points. In iron deficiency anemia (IDA), hypoxia, platelet reactivity, and potentially microRNAs play a role in the development of hypercoagulability. A total of 57 children diagnosed with IDA between October 2016 and October 2017 and 48 healthy children were included in this cross-sectional study. Blood count parameters, serum iron, transferrin saturation, ferritin level, maximum clot firmness (MCF), and clot formation time index, which are indicators of hypercoagulability in rotational thromboelastometry test, of the IDA and control groups obtained in our previous study were recorded. miR-210, miR-122, and miR-223 levels were analyzed. There was no difference in the miR-210, miR-122, and miR-223 levels between the IDA and control groups. Patients with hemoglobin (Hb) <8 g/dL had higher miR-210 levels than patients with Hb>8 g/dL (P<0.05). There was a negative correlation between miR-210 and Hb and ferritin levels, a positive correlation between miR-122 and ferritin levels, and a negative correlation between miR-223 and MCF index. In IDA, there is a close relationship between the severity of anemia and miR-210, and miR-210 expression is slightly increased in those with severe anemia. miR-210 and miR-122 collectively play a role in maintaining the iron balance. The correlation between miR-223, a platelet function regulator, and the MCF index, suggested that miR-223 has a role in the development of hypercoagulability in IDA.

MicroRNAs in β-thalassemia

β-thalassemia is a lethal inherited disease resulting from β-globin gene mutations. Severe β-thalassemia requires regular blood transfusions. Other active interventions, including iron chelating, stem cell transplantation and gene therapy, have remarkably improved the quality of life and prolonged the survival of patients with transfusion-dependent β-thalassemia, but all with significant limitations and complications. MicroRNAs (miRNAs), encoded by a class of endogenous genes, are found to play important roles in regulating globin expression. Among the miRNAs of particular interest related to β-thalassemia, miR-15a/16-1, miR-486-3p, miR-26b, miR-199b-5p, miR-210, miR-34a, miR-138, miR-326, let-7, and miR-17/92 cluster elevate γ-globin expression, while miR-96, miR-146a, miR-223-3p, and miR-144 inhibit γ-globin expression. A couple of miRNAs, miR-144 and miR-150, repress α-globin expression, whereas miR-451 induces α-, β- and γ-globin expression. Single nucleotide polymorphism in miRNA genes or their targeted genes might also contribute to the abnormal expression of hemoglobin. Moreover, changes in the expression of miR-125b, miR-210, miR-451, and miR-609 reflect the severity of anemia and hemolysis in β-thalassemia patients. These results suggest that miRNAs are potential biomarkers for the diagnosis and prognosis of β-thalassemia, and miRNA-based therapeutic strategy might be used as a coordinated approach for effectively treating β-thalassemia.

miR-30a regulates γ-globin expression in erythoid precursors of intermedia thalassemia through targeting BCL11A

Patients with β-thalassemia suffer from a lack or absence of the beta-globin chain of normal hemoglobin (Hb). Therefore, an increase in fetal Hb (HbF) levels could improve the clinical status of these patients. Downregulation of BCL11A, a key regulatory transcription factor, could ameliorate the clinical status of thalassemic patients by increasing HbF levels. miR-30a expression and its relationship with the BCL11A gene in erythroid precursors was explored in patients with β-thalassemia. The relevance of miR-30a to clinical parameters was also investigated. We evaluated the expressions of miR-30a, BCL11A, and γ-globin genes by quantitative real-time PCR (qRT-PCR) on isolated erythroid precursors from peripheral blood samples of β-thalassemia intermedia (TI) patients and in bone marrow samples from healthy individuals as controls. The correlation between miR-30a expression and clinical indices that included HbF levels, ferritin, and the frequency of blood transfusions were assessed. We observed increased expression of miR-30a in conjunction with decreased BCL11A expression and elevated γ-globin and HbF levels. Patients with elevated miR-30a expression had a higher percentage of HbF and a lower level of ferritin. In addition, we observed that overexpression of miR-30a in erythroid precursor cells led to reduced BCL11A expression and was associated with elevated γ-globin expression. Our findings showed the importance of miR-30a in BCL11A and HbF regulation, and in the clinical status of patients with β-thalassemia.

Using microarray analysis to identify genes and pathways that regulate fetal hemoglobin levels

Increased levels of fetal hemoglobin (HbF: α2γ2) can ameliorate the clinical severity of the β-hemoglobinopathies. Microarray analysis represents a powerful approach to identify novel genetic factors regulating the γ-globin gene. Gene expression profiling was previously performed on 14 individuals with high or normal HbF levels to identify the genetic factors that control γ-globin gene expression. To obtain more accurate and reliable results, our results were combined with public microarray dataset GSE22109 deposited in the Gene Expression Omnibus database. Annotation of case versus control samples was taken directly from the microarray documentation. The differentially expressed genes (DEGs) were obtained and were deeply analyzed by bioinformatics methods. Combined with our own chip expression data, potential genes HBE1, TFRC, and CSF2 were selected out for subsequent qRT-PCR validation. A total of 184 DEGs were identified from GSE22109 and the protein-protein interaction network was constructed. Gene set enrichment analysis showed that the hematopoietic cell lineage pathway overlaps in the two datasets. HBE1, CSF2, and TFRC were confirmed by qRT-PCR. Our results suggest novel candidate genes and pathways associated with the γ-globin gene expression.

MicroRNAs and Long Non-coding RNAs in Genetic Diseases

Since the discovery and classification of non-coding RNAs, their roles have gained great attention. In this respect, microRNAs and long non-coding RNAs have been firmly demonstrated to be linked to regulation of gene expression and onset of human diseases, including rare genetic diseases; therefore they are suitable targets for therapeutic intervention. This issue, in the context of rare genetic diseases, is being considered by an increasing number of research groups and is of key interest to the health community. In the case of rare genetic diseases, the possibility of developing personalized therapy in precision medicine has attracted the attention of researchers and clinicians involved in developing "orphan medicinal products" and proposing these to the European Medicines Agency (EMA) and to the Food and Drug Administration (FDA) Office of Orphan Products Development (OOPD) in the United States. The major focuses of these activities are the evaluation and development of products (drugs, biologics, devices, or medical foods) considered to be promising for diagnosis and/or treatment of rare diseases or conditions, including rare genetic diseases. In an increasing number of rare genetic diseases, analysis of microRNAs and long non-coding RNAs has been proven a promising strategy. These diseases include, but are not limited to, Duchenne muscular dystrophy, cystic fibrosis, Rett syndrome, and β-thalassemia. In conclusion, a large number of approaches based on targeting microRNAs and long non-coding RNAs are expected in the field of molecular diagnosis and therapy, with a facilitated technological transfer in the case of rare genetic diseases, in virtue of the existing regulation concerning these diseases.

The role of circulating tumour cells and nucleic acids in blood for the detection of bladder cancer: A systematic review

BACKGROUND

Blood-based biomarkers are a neglected resource in bladder cancer, where the mainstay of focus has been on urinary biomarkers. However, blood-based biomarkers are gaining popularity in other solid cancers, particularly circulating tumour cells (CTCs) and circulating nucleic acids. In this systematic review, we identify and discuss the diagnostic value of CTC, cell-free DNA and RNA based biomarkers in bladder cancer.

METHODS

A MEDLINE/Pubmed systematic search was performed using the following keywords: (bladder cancer) AND (blood OR plasma OR serum) AND biomarker AND (DNA OR RNA OR cfDNA OR cell-free DNA OR RNA OR CTC). All studies including blood-based biomarkers based on DNA, RNA and CTCs were reviewed. Of the included studies, studies reporting sensitivity, specificity and/or AUC/ROC values were further described.

RESULTS

Systematic searched yielded 47 studies that were eligible, of which 21, 19 and 3 studies reported DNA, RNA and CTC biomarkers respectively. 15 of these studies included sensitivity, specificity and/or AUC/ROC values. Biomarkers sensitivity and specificity ranged widely at 2.4-97.6% and 43.3-100% respectively. Median number of patients recruited in the studies was 56 (IQR 41-90). Only 3 studies included an independent validation cohort. The highest sensitivity and specificity pairing achieved in the validation cohort was 80.0% and 89.1% respectively.

CONCLUSIONS

This systematic review provides a comprehensive overview of the blood-based CTC and nucleic acid biomarkers that have been investigated. An overlap in interest of targets between studies suggests that these could be promising biomarkers, but few biomarkers achieve high sensitivity and specificity, and fewer still have been validated independently.