Gene expression profiling identifies a subset of adult T-cell acute lymphoblastic leukemia with myeloid-like gene features and over-expression of miR-223

MiR-223-3p in Cancer Development and Cancer Drug Resistance: Same Coin, Different Faces

MicroRNAs (miRNAs) are mighty post-transcriptional regulators in cell physiology and pathophysiology. In this review, we focus on the role of miR-223-3p (henceforth miR-223) in various cancer types. MiR-223 has established roles in hematopoiesis, inflammation, and most cancers, where it can act as either an oncogenic or oncosuppressive miRNA, depending on specific molecular landscapes. MiR-223 has also been linked to either the sensitivity or resistance of cancer cells to treatments in a context-dependent way. Through this detailed review, we highlight that for some cancers (i.e., breast, non-small cell lung carcinoma, and glioblastoma), the oncosuppressive role of miR-223 is consistently reported in the literature, while for others (i.e., colorectal, ovarian, and pancreatic cancers, and acute lymphocytic leukemia), an oncogenic role prevails. In prostate cancer and other hematological malignancies, although an oncosuppressive role is frequently described, there is less of a consensus. Intriguingly, NLRP3 and FBXW7 are consistently identified as miR-223 targets when the miRNA acts as an oncosuppressor or an oncogene, respectively, in different cancers. Our review also describes that miR-223 was increased in biological fluids or their extracellular vesicles in most of the cancers analyzed, as compared to healthy or lower-risk conditions, confirming the potential application of this miRNA as a diagnostic and prognostic biomarker in the clinic.

A novel bi-alleleic DDX41 mutations in B-cell lymphoblastic leukemia: case report

Background

The germline mutations of DDX41, also known as DEAD box RNA helicase 41, have been found in about 1.5% of myeloid neoplasms (MNs). Development of MDS/AML is relatively common in germline DDX41 mutations. However, a variety of hematological malignancies (HMs) have been reported.

Case presentation

We report a novel case of bi-alleleic DDX41 mutations in B-cell lymphoblastic leukemia (B-ALL), with unusual location of DDX41 mutations. The gene expression profile (GEP) of Ph + B-ALL with bi-alleleic DDX41 mutations showed heterogeneously transitional GEP and altered gene expression levels of genes involved in the process essential for red blood cells and myeloid cell differentiation were noted.

Conclusions

We report that DDX41 mutations are unusual but can be an underlying event in Ph + B-ALL and screening DDX41 mutations can be also informative for patients awaiting for haploidentical stem cell transplantation and choosing the therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01191-2.

Circulating miR-146a expression as a non-invasive predictive biomarker for acute lymphoblastic leukemia

Dysregulation of non-coding microRNAs during the course of tumor development, invasion and/or progression to the distant organs, makes them a promising candidate marker for the diagnosis of cancer and associated malignancies. This exploratory study aims at evaluating the usefulness of plasma concentration of circulating mir-146a as a non-invasive biomarker for acute lymphoblastic leukemia (ALL). Total RNA including miRNA was isolated from 110 plasma samples of patients (n = 66), healthy controls (n = 24) and follow up (n = 20) cases and reverse transcribed. Relative concentrations were assessed using real-time quantitative PCR and fold-change was calculated by 2^−ΔΔCt method. Finally, relative concentrations were correlated to clinicopathological factors. Patients (n = 66) were analyzed to determine fold expression of miR-146a in plasma samples of ALL. Before chemotherapy, pediatric (n = 42) and adult (n = 24) showed overexpression of miR-146a compared with healthy controls (P < 0.0001). There was no effect of age and gender on mir-146a expression in plasma. mirR-146a expression was independent of clinical and hematological features. Moreover, miR-146a levels in plasma of paired samples (n = 20) after treatment showed significant decrease in expression (P < 0.001). Expression of plasma miR-146a may be utilized as non-invasive marker to diagnose and predict prognosis in pediatric and adult patients with ALL. Moreover predicted targets may be utilized for ALL therapy in future.

The many facets of miR-223 in cancer: Oncosuppressor, oncogenic driver, therapeutic target, and biomarker of response

Given their intrinsic pleiotropism, microRNAs (miR) play complex biological roles, in both normal and pathological conditions. Often the same miR can act as oncogene or oncosuppressor, depending on the biological process dysregulated in each specific tissue. miR‐223 does not represent an exception to this rule and its functions greatly differ in different contexts. miR‐223 has been widely studied in the hematopoietic compartment, where it plays a central role in innate immune response, regulating myeloid differentiation and granulocytes function. Accordingly, dysregulated expression of miR‐223 has been associated to different inflammatory disorders and tumors arising from the immune compartment. Most carcinomas, breast cancer being the most studied, display loss of miR‐223. However, in gastro‐esophageal cancers miR‐223 is frequently overexpressed and correlates with worse prognosis. A link between miR‐223 and response to CDK4/6‐inhibitors has been recently proposed, suggesting a role as biomarker of therapeutic response. The notion that one of the most commonly mutated protein in cancer, mutant p53, binds the promoter of miR‐223 and suppresses its transcription, adds a further level of complexity to the full understanding of miR‐223 in cancer. In this review, we will summarize the current knowledge on the molecular networks that alter or are altered by miR‐223, in different cancer types. We will discuss if the times are ready for the exploitation of miR‐223 as predictive biomarker of treatment response or, even, as therapeutic target, in specific settings. Finally, we will suggest which could be the next steps to be taken for a realistic clinical application of miR‐223.

This article is categorized under:

RNA in Disease and Development > RNA in Disease

The Significance of miRNAs as a Prognostic Biomarker for Survival Outcome in T Cell - Acute Lymphoblastic Leukemia Patients: A Systematic Review and Meta-Analysis

Purpose

T-cell acute lymphoblastic leukemia (T-ALL) affects lymphoid cells. Previous studies have reported that miRNAs play a significant role in T-ALL prognosis and have the potential to function as biomarkers in T-ALL. Therefore, this systematic review and meta-analysis study was designed to evaluate the overall prognostic impact of miRNAs in T-ALL patients.

Methods

Eligible studies published between Jan 2010 and April 2018 were retrieved from online bibliographic databases based on multiple keywords to generate search strings. Meta-analysis was performed using the outcome measure, Hazard Ratio (HR). A survival analysis of all studies was conducted and a subsequent forest plot was generated to evaluate the pooled effect size, across all T-ALL patients. Subgroup analysis was conducted based on demographic characteristics and commonly represented miRNAs among the included studies.

Results

A total of 17 studies were included for systematic review, among which 16 studies were eligible for meta-analysis, which, in total discussed 32 different miRNAs. The mean effect size of HR value was 0.929 (CI 0.878–0984), which indicates a decrease in risk of death by 7.1%. The analysis was based on the random effects model with the heterogeneity measure index (I²) being 84.92%. The pooled effect size (HR) of upregulated and downregulated miRNA expressions on survival outcome in the T-ALL patient was 0.787 (CI 0.732–0.845) and 1.225 (CI 1.110–1.344) respectively. The subgroup analysis was performed based on demographic characteristics (age, gender, lactate dehydrogenase, WBC count) and expression of miR221 and miR46a.

Conclusion

Our systematic review and meta-analysis findings suggest that the overall miRNA expression is potentially associated with a decreased likelihood of death in T-ALL patients. Although our findings are inconclusive, the results point toward miRNA expression allowing for prognostic evaluation of T-ALL patients.

MicroRNA-223 Suppresses the Canonical NF-κB Pathway in Basal Keratinocytes to Dampen Neutrophilic Inflammation

MicroRNA-223 is known as a myeloid-enriched anti-inflammatory microRNA that is dysregulated in numerous inflammatory conditions. Here, we report that neutrophilic inflammation (wound response) is augmented in miR-223-deficient zebrafish, due primarily to elevated activation of the canonical nuclear factor κB (NF-κB) pathway. NF-κB over-activation is restricted to the basal layer of the surface epithelium, although miR-223 is detected throughout the epithelium and in phagocytes. Not only phagocytes but also epithelial cells are involved in miR-223-mediated regulation of neutrophils' wound response and NF-κB activation. Cul1a/b, Traf6, and Tab1 are identified as direct targets of miR-223, and their levels rise in injured epithelium lacking miR-223. In addition, miR-223 is expressed in cultured human bronchial epithelial cells, where it also downregulates NF-κB signaling. Together, this direct connection between miR-223 and the canonical NF-κB pathway provides a mechanistic understanding of the multifaceted role of miR-223 and highlights the relevance of epithelial cells in dampening neutrophil activation.

Advances in biology of acute lymphoblastic leukemia (ALL) and therapeutic implications

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer and also occurs in adults. Although the outcomes of multi-agent chemotherapy regimens have greatly improved, high toxicity and relapses in many patients necessitate the development of novel therapeutic approaches. Advances in molecular profiling and cytogenetics have identified a broad range of genetic abnormalities, including gene mutations, chromosome translocations and aneuploidy, which has provided a more comprehensive understanding of the biology and pathogenesis of ALL. This understanding has also led to new targeted therapeutic approaches, including the use of selective small molecule inhibitors, nucleic acid-based therapies and immune-based therapies mediated by specific monoclonal antibodies and cellular immunotherapy, which are poised to revolutionize the treatment of various ALL subtypes. The main focus of this review is to highlight the latest advances in ALL biology, including the identification of prognostic factors and putative therapeutic targets. We also review the current status of, and ongoing progress in, the development of targeted therapies for ALL.

Serum microRNA-126 and -223 as new-generation biomarkers for sarcoidosis in patients with heart failure

BACKGROUND

Although cardiac sarcoidosis is associated with poor prognosis, diagnosis of the disease is challenging and the sensitivity and specificity of diagnostic modalities are limited. This study was performed to evaluate the potential of serum microRNAs (miRNAs) as diagnostic biomarkers for cardiac sarcoidosis.

METHODS

We performed genome-wide expression profiling for 2565 miRNAs (Human-miRNA ver.21) using peripheral blood samples from 5 patients with cardiac sarcoidosis (61±9 years) and 3 healthy controls (54±7 years). From this screening study, we selected 12 miRNAs that were significantly related to cardiac sarcoidosis. Next, we performed real-time polymerase chain reaction (PCR) on blood samples from 15 new patients with cardiac sarcoidosis and 4 healthy controls to quantify the expression of these 12 miRNAs.

RESULTS

In the screening study, 12 miRNAs were differentially expressed (p<0.01) in all 5 patients with cardiac sarcoidosis, showing greater fold-change values (>4 or <0.25) compared with the expression in the 3 healthy controls. Analysis of the real-time PCR for blood samples from the other 15 patients and 4 controls using Mann-Whitney U tests revealed that the expression of miR-126 and miR-223 was significantly higher in the patients than in the healthy individuals. However, there were no differences in the expressions of miRNA-126 and miR-223 between patients with only cardiac lesions and those with extra-cardiac lesions.

CONCLUSIONS

Our results demonstrate the potential of serum miR-126 and miR-223 as new-generation biomarkers for the differential diagnosis of cardiac sarcoidosis in patients with heart failure.

MicroRNA expression and activity in T-cell acute lymphoblastic leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is a lymphoid malignancy caused by the oncogenic transformation of immature T-cell progenitors. Many biologically relevant genetic and epigenetic alterations have been identified as driving factors for this transformation. Recently, microRNAs (miRNAs) have been shown to influence various leukemias, including T-ALL. Aberrant expression of miRNAs can function as either oncogenes or tumor suppressors in T-ALL through the regulation of cell migration, invasion, proliferation, apoptosis, and chemoresistance. This occurs by targeting key signaling pathways or transcriptional factors that play a critical role in T-ALL pathology and progression. Different miRNA expression profiles have been linked to specific genetic subtypes of human T-ALL. Furthermore, miRNAs can also act as independent prognostic factors to predict clinical outcomes for T-ALL patients. In the current review, we will focus on the role of miRNAs in the development and progression of T-ALL.

Immune Modulatory microRNAs Involved in Tumor Attack and Tumor Immune Escape

Current therapies against cancer utilize the patient's immune system for tumor eradication. However, tumor cells can evade immune surveillance of CD8+ T and/or natural killer (NK) cells by various strategies. These include the aberrant expression of human leukocyte antigen (HLA) class I antigens, co-inhibitory or costimulatory molecules, and components of the interferon (IFN) signal transduction pathway. In addition, alterations of the tumor microenvironment could interfere with efficient antitumor immune responses by downregulating or inhibiting the frequency and/or functional activity of immune effector cells and professional antigen-presenting cells. Recently, microRNAs (miRNAs) have been identified as major players in the post-transcriptional regulation of gene expression, thereby controlling many physiological and also pathophysiological processes including neoplastic transformation. Indeed, the cellular miRNA expression pattern is frequently altered in many tumors of distinct origin, demonstrating the tumor suppressive or oncogenic potential of miRNAs. Furthermore, there is increasing evidence that miRNAs could also influence antitumor immune responses by affecting the expression of immune modulatory molecules in tumor and immune cells. Apart from their important role in tumor immune escape and altered tumor-host interaction, immune modulatory miRNAs often exert neoplastic properties, thus representing promising targets for future combined immunotherapy approaches. This review focuses on the characterization of miRNAs involved in the regulation of immune surveillance or immune escape of tumors and their potential use as diagnostic and prognostic biomarkers or as therapeutic targets.

TP53 in adult acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is characterized by a great biological and clinical heterogeneity. Despite most adult patients enter complete hematologic remission after induction therapy only 40% survive five or more years. Over the last 20 years, the definition of an accurate biologic leukemia profile and the minimal residual disease evaluation in addition to conventional risk criteria led to a significant improvement for the risk stratification. The alterations of the oncosuppressor gene TP53, including deletions, sequence mutations and defect in its expression due to regulatory defects, define a new important predictor of adverse outcome. More recently, new drugs have been developed with the aim of targeting p53 protein itself or its regulatory molecules, such as Mdm2, and restoring the pathway functionality. Therefore, TP53 alterations should be considered in the diagnostic work-up to identify high risk ALL patients in need of intensive treatment strategies or eligible for new innovative targeted therapies.

Regulation of PI3K signaling in T-cell acute lymphoblastic leukemia: a novel PTEN/Ikaros/miR-26b mechanism reveals a critical targetable role for PIK3CD

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy, and T-ALL patients are prone to early disease relapse and suffer from poor outcomes. The PTEN, PI3K/AKT, and Notch pathways are frequently altered in T-ALL. PTEN is a tumor suppressor that inactivates the PI3K pathway. We profiled miRNAs in Pten-deficient mouse T-ALL and identified miR-26b as a potentially dysregulated gene. We validated decreased expression levels of miR-26b in mouse and human T-ALL cells. In addition, expression of exogenous miR-26b reduced proliferation and promoted apoptosis of T-ALL cells in vitro, and hindered progression of T-ALL in vivo. Furthermore, miR-26b inhibited the PI3K/AKT pathway by directly targeting PIK3CD, the gene encoding PI3Kδ, in human T-ALL cell lines. ShRNA for PIK3CD and CAL-101, a PIK3CD inhibitor, reduced the growth and increased apoptosis of T-ALL cells. Finally, we showed that PTEN induced miR-26b expression by regulating the differential expression of Ikaros isoforms that are transcriptional regulators of miR-26b. These results suggest that miR-26b functions as a tumor suppressor in the development of T-ALL. Further characterization of targets and regulators of miR-26b may be promising for the development of novel therapies.

T-ALL and thymocytes: a message of noncoding RNAs

In the last decade, the role for noncoding RNAs in disease was clearly established, starting with microRNAs and later expanded towards long noncoding RNAs. This was also the case for T cell acute lymphoblastic leukemia, which is a malignant blood disorder arising from oncogenic events during normal T cell development in the thymus. By studying the transcriptomic profile of protein-coding genes, several oncogenic events leading to T cell acute lymphoblastic leukemia (T-ALL) could be identified. In recent years, it became apparent that several of these oncogenes function via microRNAs and long noncoding RNAs. In this review, we give a detailed overview of the studies that describe the noncoding RNAome in T-ALL oncogenesis and normal T cell development.

Advances in the Genetics and Therapy of Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) remains an important cause of morbidity in children and adults. In this article, we highlight advances in the genetics and therapy of three key subtypes of ALL: T-cell ALL, BCR-ABL1 (Philadelphia [Ph] chromosone-positive), and Ph-like ALL. T-ALL is an aggressive disease that accounts for about 15% and 25% of ALL among pediatric and adult cohorts, respectively, and exhibits a multistep nature of cancer initiation and progression. The integration of cytogenetics, molecular biology, and immunophenotype analyses has led to the identification of defined T-ALL subgroups, such as early T-cell precursor ALL and novel lesions with a prognostic role, for which specific inhibitors are being developed. Ph-positive ALL was historically regarded as a subtype of ALL with a poor prognosis, and allogeneic stem cell transplant was recommended for all patients who could undergo this procedure. The deep complete responses seen with combination tyrosine kinase inhibitors (TKIs) and chemotherapy in Ph-positive ALL, and the reports of long-term survival among some patients not undergoing allogeneic stem cell transplant, has raised the question of whether there is a subset of patients who could be cured without this intervention. Ph-like ALL is a subtype of B-progenitor ALL common among older children and adults and associated with a diverse range of genetic alterations that activate kinase signaling. Ph-like ALL is also associated with poor outcome, for which precision medicine trials identifying kinase alterations and testing TKI therapy are being developed.

miR‑223‑3p regulates cell growth and apoptosis via FBXW7 suggesting an oncogenic role in human testicular germ cell tumors

miR-223-3p is deregulated in several tumor types and plays an important role in tumorigenesis and progression. However, its role in the pathogenesis of testicular germ cell tumor (TGCT) remains uncharacterized. We previously demonstrated that miR-223-3p expression was increased in TGCTs compared with normal testes (NT), suggesting that miR-223-3p may have an oncogenic role in TGCT. Using published dataset and The Cancer Genome Atlas database, we validated higher miR-223-3p expression in TGCTs than NT, and found a negative correlation between miR-223-3p and FBXW7 mRNA expression levels. Using both gain- and loss-of-function experiments, we show that miR-223-3p regulates FBXW7 protein expression, cell growth and apoptosis in TGCT cell lines. Additionally, we demonstrate that ectopic expression of the full-length coding sequence of FBXW7 could rescue the cell growth and apoptotic effects mediated by miR-223-3p. Our findings suggest an oncogenic role for miR-223-3p in TGCT, which promotes cell growth and inhibits apoptosis through repression of FBXW7.

Dimension reduction techniques for the integrative analysis of multi-omics data

State-of-the-art next-generation sequencing, transcriptomics, proteomics and other high-throughput 'omics' technologies enable the efficient generation of large experimental data sets. These data may yield unprecedented knowledge about molecular pathways in cells and their role in disease. Dimension reduction approaches have been widely used in exploratory analysis of single omics data sets. This review will focus on dimension reduction approaches for simultaneous exploratory analyses of multiple data sets. These methods extract the linear relationships that best explain the correlated structure across data sets, the variability both within and between variables (or observations) and may highlight data issues such as batch effects or outliers. We explore dimension reduction techniques as one of the emerging approaches for data integration, and how these can be applied to increase our understanding of biological systems in normal physiological function and disease.

miRNA-223 is a potential diagnostic and prognostic marker for osteosarcoma

Background

MicroRNA-223 (miR-223) has been shown to be a potential diagnostic and prognostic marker for several cancers. In addition, miR-223 has been reported to suppress osteosarcoma cell proliferation in vitro. However, the clinical value of miR-223 is still unknown.

Methods

We detected the expression of miR-223 expression in the serum of osteosarcoma patients and in osteosarcoma cancer cells using RT-PCR. We compared the serum expression of miR-223 with the clinicopathological characteristics and survival of osteosarcoma patients. Finally, we explored the role of miR-223 on the invasion of osteosarcoma cancer cells using cell migration and invasion assays.

Results

We observed that the expression of miR-223 was significantly decreased in the serum of osteosarcoma patients and osteosarcoma cancer cells compared to healthy controls (P<0.01). Moreover, a receiver operating characteristic (ROC) curve analysis indicated that serum miR-223 is a potential diagnostic marker of osteosarcoma with an area under the ROC curve (AUC) of 0.956. Importantly, the patients with a lower expression of miR-223 tended to have distant metastasis (P<0.001) and a more advanced clinical stage (P<0.001). In addition, the survival time of patients with low miR-223 expression was significantly shorter compared to patients with high miR-223 expression (P<0.001). Furthermore, we found that miR-223 could inhibit the migration and invasion of osteosarcoma cells.

Conclusions

miR-223 might be related to the metastasis of osteosarcoma and could be used as a potential diagnostic and prognostic biomarker in osteosarcoma.

The functional role of microRNA in acute lymphoblastic leukemia: relevance for diagnosis, differential diagnosis, prognosis, and therapy

MicroRNAs (miRNAs), a new class of noncoding RNAs, which can hybridize to target messenger RNAs and regulate their expression posttranscriptionally, express differentially in distinct stages of lymphopoiesis and influence the direction of lymphoid precursor maturation. Hence, there is aberrant expression of miRNAs involved in malignant lymphopoiesis, and these aberrations can be used as signatures of acute lymphoblastic leukemia (ALL) with different subtypes. In addition, changes in the expression of several miRNAs may have functional relevance with leukemogenesis or drug resistance. As a result, the reversal of the expression of these miRNAs may alleviate the disease to some extent and improve clinical outcomes. However, among the studies of miRNAs, there are still some problems that need to be solved to understand the function of miRNAs in ALL more thoroughly.

Aberrant regulation of FBW7 in cancer

FBW7 (F-box and WD repeat domain-containing 7) or Fbxw7 is a tumor suppressor, which promotes the ubiquitination and subsequent degradation of numerous oncoproteins including Mcl-1, Cyclin E, Notch, c- Jun, and c-Myc. In turn, FBW7 is regulated by multiple upstream factors including p53, C/EBP-δ, EBP2, Pin1, Hes-5 and Numb4 as well as by microRNAs such as miR-223, miR-27a, miR-25, and miR-129-5p. Given that the Fbw7 tumor suppressor is frequently inactivated or deleted in various human cancers, targeting FBW7 regulators is a promising anti-cancer therapeutic strategy.

Involvement of MicroRNA in T-Cell Differentiation and Malignancy

MicroRNAs are 19-22 nucleotide RNAs involved in such important processes as development, proliferation, differentiation and apoptosis. Different miRNAs are uniquely expressed in lymphoid T cells, and play a role indevelopment and differentiation of various subtypes by targeting their target genes. Recent studies have shown that aberrant miRNA expression may be involved in T cell leukemogenesis and lymphogenesis, and may function as tumor suppressor (such as miR-451, miR-31, miR-150, and miR-29a) or oncogene (e.g. miR-222, miR-223, miR-17-92, miR-155). MiRNAs can be used as new biomarkers for prognosis and diagnosis or as an index of disease severity in T-cell leukemia and lymphoma. This article presents a review of studies in recent years on the role of miRNAs in T-cell development and their aberrant expression in pathogenesis of T-cell leukemia and lymphoma. Characterizing miRNAs can help recognize their role as new important molecules with prognostic and therapeutic applications.

Diagnosis and subclassification of acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is a disseminated malignancy of B- or T-lymphoblasts which imposes a rapid and accurate diagnostic process to support an optimal risk-oriented therapy and thus increase the curability rate. The need for a precise diagnostic algorithm is underlined by the awareness that both ALL therapy and related success rates may vary greatly between ALL subsets, from standard chemotherapy in patients with standard-risk ALL, to allotransplantation (SCT) and targeted therapy in high-risk patients and cases expressing suitable biological targets, respectively. This review summarizes how best to identify ALL and the most relevant ALL subsets.

Genomic characterization of acute leukemias

Over the past two decades, hematologic malignancies have been extensively evaluated due to the introduction of powerful technologies, such as conventional karyotyping, FISH analysis, gene and microRNA expression profiling, array comparative genomic hybridization and SNP arrays, and next-generation sequencing (including whole-exome sequencing and RNA-seq). These analyses have allowed for the refinement of the mechanisms underlying the leukemic transformation in several oncohematologic disorders and, more importantly, they have permitted the definition of novel prognostic algorithms aimed at stratifying patients at the onset of disease and, consequently, treating them in the most appropriate manner. Furthermore, the identification of specific molecular markers is opening the door to targeted and personalized medicine. The most important findings on novel acquisitions in the context of acute lymphoblastic leukemia of both B and T lineage and de novo acute myeloid leukemia are described in this review.

The downregulation of PRDM1/Blimp-1 is associated with aberrant expression of miR-223 in extranodal NK/T-cell lymphoma, nasal type

BACKGROUND

The mechanism for inactivation of positive regulatory domain containing I (PRDM1), a newly identified tumour suppressor gene in extranodal NK/T-cell lymphoma, nasal type (EN-NK/T-NT) has not been well defined. The aim of the present study was to investigate the expression of PRDM1 in EN-NK/T-NT and analyse its downregulation by miRNAs.

METHODS

PRDM1 and miRNA expression were evaluated in EN-NK/T-NT samples by immunohistochemical analysis, qRT-PCR, and in situ hybridisation. Luciferase assays were performed to verify the direct binding of miR-223 to the 3'-untranslated region of PRDM1 mRNA. In addition, the effect of miR-223 on PRDM1 expression was assessed in NK/T lymphoma cell lines by transfecting a miR-223 mimic or inhibitor to increase or decrease the effective expression of miR-223. Overall survival and failure-free survival in EN-NK/T-NT patients were analysed using Kaplan-Meier single-factor analysis and the log-rank test.

RESULTS

Investigation of the downregulation of PRDM1 in EN-NK/T-NT cases revealed that PRDM1-positive staining might be a favourable predictor of overall survival and failure-free survival in EN-NK/T-NT patients. However, the negative staining of PRDM1 usually presented transcripts, suggesting a possible post-transcriptional regulation. miR-223 and its putative target gene, PRDM1, exhibited opposite patterns of expression in EN-NK/T-NT tissues and cell lines. Moreover, PRDM1 was identified as a direct target gene of miR-223 by luciferase assays. The ectopic expression of miR-223 led to the downregulation of the PRDM1 protein in the NK/T-cell lymphoma cell line, whereas a decrease in miR-223 restored the level of PRDM1 protein.

CONCLUSIONS

Our findings reveal that the downregulation of the tumour suppressor PRDM1 in EN-NK/T-NT samples is mediated by miR-223 and that PRDM1-positive staining might have prognostic value for evaluating the clinical outcome of EN-NK/T-NT patients.

miR-223: infection, inflammation and cancer

Expression of the microRNA miR-223 is deregulated during influenza or hepatitis B infection and in inflammatory bowel disease, type 2 diabetes, leukaemia and lymphoma. Although this may also be the result of the disease per se, increasing evidence suggests a role for miR-223 in limiting inflammation to prevent collateral damage during infection and in preventing oncogenic myeloid transformation. Validated targets for miR-223 that have effects on inflammation and infection include granzyme B, IKKα, Roquin and STAT3. With regard to cancer, validated targets include C/EBPβ, E2F1, FOXO1 and NFI-A. The effect of miR-223 on these targets has been documented individually; however, it is more likely that miR-223 affects multiple targets simultaneously for key processes where the microRNA is important. Such processes include haematopoietic cell differentiation, particularly towards the granulocyte lineage (where miR-223 is abundant) and as cells progress down the myeloid lineage (where miR-223 expression decreases). NF-κB and the NLRP3 inflammasome are important inflammatory mechanisms that are dampened by miR-223 in these cell types. The miRNA can also directly target viruses such as HIV, leading to synergistic effects during infection. Here we review the recent studies of miR-223 function to show how it modulates inflammation, infection and cancer development.

Maternal and cord blood miR-223 expression associates with prenatal tobacco smoke exposure and low regulatory T-cell numbers

BACKGROUND

There is evidence that microRNAs (miRNAs) are sensitive to environmental stressors, including tobacco smoke. On the other hand, miRNAs are involved in immune regulation, such as regulatory T (Treg) cell differentiation. The aim of the present study was to investigate the association between prenatal tobacco smoke exposure, miRNAs, and Treg cell numbers.

METHODS

Within a prospective mother-child study (Lifestyle and Environmental Factors and Their Influence on Newborns Allergy Risk), we analyzed the expression of miR-155 and miR-223 together with Treg cell numbers in maternal blood during pregnancy, as well as in cord blood (n = 441). Tobacco smoke exposure was assessed based on questionnaire answers and maternal urine cotinine levels. Additionally, the concentration of smoking-related volatile organic compounds was measured in dwellings of study participants.

RESULTS

Both maternal and cord blood miR-223 expressions were positively correlated with maternal urine cotinine levels. An association was also found between maternal miR-223 expression and indoor concentrations of benzene and toluene. High miR-223 expression was associated with lower Treg cell numbers in maternal and cord blood. Furthermore, children with lower Treg cell numbers at birth had a higher risk of atopic dermatitis during the first 3 years of life. The concentration of the toluene metabolite S-benzylmercapturic acid in maternal urine was associated with decreased cord blood, but not maternal blood, miR-155 expression. A relationship between miR-155 expression and Treg cell numbers was not found.

CONCLUSIONS

For the first time, we show that maternal tobacco smoke exposure during pregnancy correlates with the level of miRNA-223 expression in blood, with an effect on children's cord blood Treg cell numbers and subsequent allergy risk.

The TAL1 complex targets the FBXW7 tumor suppressor by activating miR-223 in human T cell acute lymphoblastic leukemia

miR-223 is upregulated by the transcription factor TAL1 in human T-ALL cells and suppress the FBXW7 tumor suppressor.

The oncogenic transcription factor TAL1/SCL is aberrantly expressed in 60% of cases of human T cell acute lymphoblastic leukemia (T-ALL) and initiates T-ALL in mouse models. By performing global microRNA (miRNA) expression profiling after depletion of TAL1, together with genome-wide analysis of TAL1 occupancy by chromatin immunoprecipitation coupled to massively parallel DNA sequencing, we identified the miRNA genes directly controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GATA3, and RUNX1. The most dynamically regulated miRNA was miR-223, which is bound at its promoter and up-regulated by the TAL1 complex. miR-223 expression mirrors TAL1 levels during thymic development, with high expression in early thymocytes and marked down-regulation after the double-negative-2 stage of maturation. We demonstrate that aberrant miR-223 up-regulation by TAL1 is important for optimal growth of TAL1-positive T-ALL cells and that sustained expression of miR-223 partially rescues T-ALL cells after TAL1 knockdown. Overexpression of miR-223 also leads to marked down-regulation of FBXW7 protein expression, whereas knockdown of TAL1 leads to up-regulation of FBXW7 protein levels, with a marked reduction of its substrates MYC, MYB, NOTCH1, and CYCLIN E. We conclude that TAL1-mediated up-regulation of miR-223 promotes the malignant phenotype in T-ALL through repression of the FBXW7 tumor suppressor.

Increased expression of miR-221 is associated with shorter overall survival in T-cell acute lymphoid leukemia

Background

CD56 expression has been associated with a poor prognosis in lymphoid neoplasms, including T-cell acute lymphoblastic leukemia (T-ALL). MicroRNAs (miRNAs) play an important role in lymphoid differentiation, and aberrant miRNA expression has been associated with treatment outcome in lymphoid malignancies. Here, we evaluated miRNA expression profiles in normal thymocytes, mature T-cells, and T-ALL samples with and without CD56 expression and correlated microRNA expression with treatment outcome.

Methods

The gene expression profile of 164 miRNAs were compared for T-ALL/CD56⁺ (n=12) and T-ALL/CD56^- (n=36) patients by Real-Time Quantitative PCR. Based on this analysis, we decided to evaluate miR-221 and miR-374 expression in individual leukemic and normal samples.

Results

miR-221 and miR-374 were expressed at significantly higher levels in T-ALL/CD56⁺ than in T-ALL/CD56^- cells and in leukemic blasts compared with normal thymocytes and peripheral blood (PB) T-cells. Age at diagnosis (15 or less vs grater than 15 years; HR: 2.19, 95% CI: 0.98-4.85; P=0.05), miR-221 expression level (median value as cut off in leukemic samples; HR: 3.17, 95% CI: 1.45-6.92; P=0.004), and the expression of CD56 (CD56^-vs CD56⁺; HR: 2.99, 95% CI: 1.37-6.51; P=0.006) were predictive factors for shorter overall survival; whereas, only CD56 expression (HR: 2.73, 95% CI: 1.03-7.18; P=0.041) was associated with a shorter disease-free survival rate.

Conclusions

miR-221 is highly expressed in T-ALL and its expression level may be associated with a poorer prognosis.

MiR-223/Ect2/p21 signaling regulates osteosarcoma cell cycle progression and proliferation

Osteosarcoma is one of the most common tumors. The mechanisms of formation and development of osteosarcoma have been studied for a long time. Recently, more and more evidence showed that miRNAs play important roles in regulating tumor growth. In this study we found that miRNA-223 was downregulated in both osteosarcoma patients' tumor tissues and osteosarcoma cell lines. Overexpression of miRNA-233 greatly inhibited the proliferation of Saos-2 cells. Cell cycle analysis by flow cytometry showed the arrest of cell cycle progression at the G1 phase. Further mechanistic study indicated that Ect2 was directly targeted by miR-223. Downregulation of Ect2 by miR-223 induces the expression of p21, p27 and the phospharylation of retinoblastoma, which are involved in the G1 block. We concluded that miR-223 functions as a tumor suppresser in osteosarcoma and miR-223/Ect2/p21 signaling is an important pathway that regulates the osteosarcoma cell cycle progression and proliferaion.

MicroRNA Deregulations in Head and Neck Squamous Cell Carcinomas

Objectives

Head and neck/oral cancer, predominantly head and neck squamous cell carcinoma (HNSCC), is the sixth most common cancer in the world. While substantial advances have been made to define the genomic alterations associated with head and neck/oral cancer, most studies are focused on protein coding genes. The aim of this article is to review the current literature on identified genomic aberrations of non-coding genes (e.g., microRNA) in head and neck/oral cancer (HNOC), and their contribution to the initiation and progression of HNOC.

Material and Methods

A comprehensive review of the available literature relevant to microRNA deregulation in HNSCC/HNOC, was undertaken using PubMed, Medline, Scholar Google and Scopus. Keywords for the search were: microRNA and oral cancer, microRNA and squamous cell carcinoma, microRNA deregulation and oral cancer, microRNA and carcinogenesis in the head and neck/oral cavity. Only full length articles in the English language were included.

Results

We recently identified a panel of microRNA deregulations that were consistently observed in HNSCC [Chen et al., Oral Oncol. 2012;48(8):686-91], including 7 consistently up-regulated microRNAs (miR-21, miR-7, miR-155, miR-130b, miR-223, miR-34b), and 4 consistently down-regulated microRNAs (miR-100, miR-99a, miR-125b, miR-375). In this review, we will first provide an overview on microRNA and HNSCC. We will then provide a comprehensive review on the roles of microRNA deregulations in HNSCC. The functional significance of the identified HNSCC-associated microRNAs and a number of other relevant microRNAs (e.g., miR-138, miR-98, miR-137, miR-193a and miR-218) will be discussed in detail.

Conclusions

Based on current literature, microRNA deregulation plays a major role in head and neck/oral cancer.

MicroRNA profiling reveals aberrant microRNA expression in adult ETP-ALL and functional studies implicate a role for miR-222 in acute leukemia

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has been identified as high-risk subgroup in acute T-cell lymphoblastic leukemia (T-ALL). To investigate the immature and myeloid nature of ETP-ALL we examined global microRNA (miRNA) expression in adult ETP-ALL. miRNA profiling of ETP-ALL (n=8), non-ETP T-ALL (n=6), and healthy controls was performed and results were validated in independent cohorts of 66 ETP-ALL and 111 non-ETP T-ALL using real-time RT-PCR. Furthermore, in vitro studies were performed on deregulated miRNAs in acute leukemia. We identified miR-221 and miR-222 as the most upregulated and six miRNAs (miR-151-3p, miR-19a, miR-20b, miR-342-3p, miR-363, and miR-576-3p) as downregulated in ETP-ALL compared to non-ETP T-ALL. In the validation cohorts, miR-221 and miR-222 were significantly upregulated in ETP-ALL, and miR-363 and miR-19a were downregulated in ETP-ALL. ETS1, downregulated in ETP-ALL, was identified as direct target of miR-222. In our in vitro studies miR-222 significantly inhibited proliferation, and caused cell cycle arrest and apoptosis in leukemic cells. In conclusion, our study revealed aberrant miRNA expression in ETP-ALL, with miR-221 and miR-222 as the most overexpressed miRNAs and implied a functional role for miR-222 in leukemic cells. Importantly, miR-222 may impact leukemogenesis by altering expression of the proto-oncogene ETS1 in acute leukemia.

Circulating miR-17, miR-20a, miR-29c, and miR-223 combined as non-invasive biomarkers in nasopharyngeal carcinoma

Background

MicroRNAs have been considered as a kind of potential novel biomarker for cancer detection due to their remarkable stability in the blood and the characteristics of their expression profile in many diseases.

Methods

We performed microarray-based serum miRNA profiling on the serum of twenty nasopharyngeal carcinoma patients at diagnosis along with 20 non-cancerous individuals as controls. This was followed by a real-time quantitative Polymerase Chain Reaction (RT-qPCR) in a separate cohort of thirty patients with nasopharyngeal carcinoma and thirty age- matched non-cancerous volunteers. A model for diagnosis was established by a conversion of mathematical calculation formula which has been validated by analyzing 74 cases of patients with nasopharyngeal carcinoma and 57 cases of non-cancerous volunteers.

Results

The profiles showed that 39 and 17 miRNAs are exclusively expressed in the serum of non-cancerous volunteers and of patients with nasopharyngeal carcinoma respectively. 4 miRNAs including miR-17, miR-20a, miR-29c, and miR-223 were found to be expressed differentially in the serum of NPC compared with that of non-cancerous control. Based on this, a diagnosis equation with Ct difference method has been established to distinguish NPC cases and non-cancerous controls and validated with high sensitivity and specificity.

Conclusions

We demonstrate that the serum miRNA-based biomarker model become a novel tool for NPC detection. The circulating 4-miRNA-based method may provide a novel strategy for NPC diagnosis.

Notch-mediated repression of miR-223 contributes to IGF1R regulation in T-ALL

To identify microRNAs regulated by oncogenic Notch signaling, we performed microarray-based miRNA profiling of T-cell acute lymphoblastic leukemia (T-ALL) cells before and after treatment with γ-secretase inhibitor (GSI) to block Notch signaling. We show miR-223 levels increase after GSI treatment suggesting that active Notch signaling represses miR-223 expression. We also demonstrate that insulin-like growth factor-1 receptor (IGF1R) is regulated by miR-223 in this context, but observe no apparent effects on cell growth by overexpression or knock-down of miR-223 alone. We conclude that miR-223 contributes to IGF1R regulation, but may act in concert with other genes and/or microRNAs to alter T-ALL biology.

Clinical and molecular characterization of early T-cell precursor leukemia: a high-risk subgroup in adult T-ALL with a high frequency of FLT3 mutations

A subgroup of pediatric acute T-lymphoblastic leukemia (T-ALL) was characterized by a gene expression profile comparable to that of early T-cell precursors (ETPs) with a highly unfavorable outcome. We have investigated clinical and molecular characteristics of the ETP-ALL subgroup in adult T-ALL. As ETP-ALL represents a subgroup of early T-ALL we particularly focused on this cohort and identified 178 adult patients enrolled in the German Acute Lymphoblastic Leukemia Multicenter studies (05/93–07/03). Of these, 32% (57/178) were classified as ETP-ALL based on their characteristic immunophenotype. The outcome of adults with ETP-ALL was poor with an overall survival of only 35% at 10 years, comparable to the inferior outcome of early T-ALL with 38%. The molecular characterization of adult ETP-ALL revealed distinct alterations with overexpression of stem cell-related genes (BAALC, IGFBP7, MN1, WT1). Interestingly, we found a low rate of NOTCH1 mutations and no FBXW7 mutations in adult ETP-ALL. In contrast, FLT3 mutations, rare in the overall cohort of T-ALL, were very frequent and nearly exclusively found in ETP-ALL characterized by a specific immunophenotype. These molecular characteristics provide biologic insights and implications with respect to innovative treatment strategies (for example, tyrosine kinase inhibitors) for this high-risk subgroup of adult ETP-ALL.

Abnormal microRNA expression in Ts65Dn hippocampus and whole blood: contributions to Down syndrome phenotypes

Down syndrome (DS; trisomy 21) is one of the most common genetic causes of intellectual disability, which is attributed to triplication of genes located on chromosome 21. Elevated levels of several microRNAs (miRNAs) located on chromosome 21 have been reported in human DS heart and brain tissues. The Ts65Dn mouse model is the most investigated DS model with a triplicated segment of mouse chromosome 16 harboring genes orthologous to those on human chromosome 21. Using ABI TaqMan miRNA arrays, we found a set of miRNAs that were significantly up- or downregulated in the Ts65Dn hippocampus compared to euploid controls. Furthermore, miR-155 and miR-802 showed significant overexpression in the Ts65Dn hippocampus, thereby confirming results of previous studies. Interestingly, miR-155 and miR-802 were also overexpressed in the Ts65Dn whole blood but not in lung tissue. We also found overexpression of the miR-155 precursors, pri- and pre-miR-155 derived from the miR-155 host gene, known as B cell integration cluster, suggesting enhanced biogenesis of miR-155. Bioinformatic analysis revealed that neurodevelopment, differentiation of neuroglia, apoptosis, cell cycle, and signaling pathways including ERK/MAPK, protein kinase C, phosphatidylinositol 3-kinase, m-TOR and calcium signaling are likely targets of these miRNAs. We selected some of these potential gene targets and found downregulation of mRNA encoding Ship1, Mecp2 and Ezh2 in Ts65Dn hippocampus. Interestingly, the miR-155 target gene Ship1 (inositol phosphatase) was also downregulated in Ts65Dn whole blood but not in lung tissue. Our findings provide insights into miRNA-mediated gene regulation in Ts65Dn mice and their potential contribution to impaired hippocampal synaptic plasticity and neurogenesis, as well as hemopoietic abnormalities observed in DS.

A set of miRNAs that involve in the pathways of drug resistance and leukemic stem-cell differentiation is associated with the risk of relapse and glucocorticoid response in childhood ALL

Relapse is a major challenge in the successful treatment of childhood acute lymphoblastic leukemia (ALL). Despite intensive research efforts, the mechanisms of ALL relapse are still not fully understood. An understanding of the molecular mechanisms underlying treatment outcome, therapy response and the biology of relapse is required. In this study, we carried out a genome-wide microRNA (miRNA) microarray analysis to determine the miRNA expression profiles and relapse-associated miRNA patterns in a panel of matched diagnosis–relapse or diagnosis–complete remission (CR) childhood ALL samples. A set of miRNAs differentially expressed either in relapsed patients or at diagnosis compared with CR was further validated by quantitative real-time polymerase chain reaction in an independent sample set. Analysis of the predicted functions of target genes based on gene ontology ‘biological process’ categories revealed that the abnormally expressed miRNAs are associated with oncogenesis, classical multidrug resistance pathways and leukemic stem cell self-renewal and differentiation pathways. Several targets of the miRNAs associated with ALL relapse were experimentally validated, including FOXO3, BMI1 and E2F1. We further investigated the association of these dysregulated miRNAs with clinical outcome and confirmed significant associations for miR-708, miR-223 and miR-27a with individual relapse-free survival. Notably, miR-708 was also found to be associated with the in vivo glucocorticoid therapy response and with disease risk stratification. These miRNAs and their targets might be used to optimize anti-leukemic therapy, and serve as novel targets for development of new countermeasures of leukemia. This fundamental study may also contribute to establish the mechanisms of relapse in other cancers.

MicroRNA-223 regulates cyclin E activity by modulating expression of F-box and WD-40 domain protein 7

F-box and WD-40 domain protein 7 (Fbw7) provides substrate specificity for the Skp1-Cullin1-F-box protein (SCF) ubiquitin ligase complex that targets multiple oncoproteins for degradation, including cyclin E, c-Myc, c-Jun, Notch, and mammalian target of rapamycin (mTOR). Fbw7 is a bona fide tumor suppressor, and loss-of-function mutations in FBXW7 have been identified in diverse human tumors. Although much is known about targets of the Fbw7 ubiquitin ligase pathway, relatively little is known about the regulation of Fbw7 expression. We identified a panel of candidate microRNA regulators of Fbw7 expression within a study of gene expression alterations in primary erythroblasts obtained from cyclin E(T74A T393A) knock-in mice, which have markedly dysregulated cyclin E expression. We found that overexpression of miR-223, in particular, significantly reduces FBXW7 mRNA levels, increases endogenous cyclin E protein and activity levels, and increases genomic instability. We next confirmed that miR-223 targets the FBXW7 3'-untranslated region. We then found that reduced miR-223 expression in primary mouse embryonic fibroblasts leads to increased Fbw7 expression and decreased cyclin E activity. Finally, we found that miR-223 expression is responsive to acute alterations in cyclin E regulation by the Fbw7 pathway. Together, our data indicate that miR-223 regulates Fbw7 expression and provide the first evidence that activity of the SCF(Fbw7) ubiquitin ligase can be modulated directly by the microRNA pathway.