The clinical characteristics and prognostic significance of AID, miR-181b, and miR-155 expression in adult patients with de novo B-cell acute lymphoblastic leukemia

EBV and 1q Gains Affect Gene and miRNA Expression in Burkitt Lymphoma

Abnormalities of the long arm of chromosome 1 (1q) represent the most frequent secondary chromosomal aberrations in Burkitt lymphoma (BL) and are observed almost exclusively in EBV-negative BL cell lines (BL-CLs). To verify chromosomal abnormalities, we cytogenetically investigated EBV-negative BL patient material, and to elucidate the 1q gain impact on gene expression, we performed qPCR with six 1q-resident genes and analyzed miRNA expression in BL-CLs. We observed 1q aberrations in the form of duplications, inverted duplications, isodicentric chromosome idic(1)(q10), and the accumulation of 1q12 breakpoints, and we assigned 1q21.2-q32 as a commonly gained region in EBV-negative BL patients. We detected MCL1, ARNT, MLLT11, PDBXIP1, and FCRL5, and 64 miRNAs, showing EBV- and 1q-gain-dependent dysregulation in BL-CLs. We observed MCL1, MLLT11, PDBXIP1, and 1q-resident miRNAs, hsa-miR-9, hsa-miR-9*, hsa-miR-92b, hsa-miR-181a, and hsa-miR-181b, showing copy-number-dependent upregulation in BL-CLs with 1q gains. MLLT11, hsa-miR-181a, hsa-miR-181b, and hsa-miR-183 showed exclusive 1q-gains-dependent and FCRL5, hsa-miR-21, hsa-miR-155, hsa-miR-155*, hsa-miR-221, and hsa-miR-222 showed exclusive EBV-dependent upregulation. We confirmed previous data, e.g., regarding the EBV dependence of hsa-miR-17-92 cluster members, and obtained detailed information considering 1q gains in EBV-negative and EBV-positive BL-CLs. Altogether, our data provide evidence for a non-random involvement of 1q gains in BL and contribute to enlightening and understanding the EBV-negative and EBV-positive BL pathogenesis.

The off-target effects of AID in carcinogenesis

Activation-induced cytidine deaminase (AID) plays a crucial role in promoting B cell diversification through somatic hypermutation (SHM) and class switch recombination (CSR). While AID is primarily associated with the physiological function of humoral immune response, it has also been linked to the initiation and progression of lymphomas. Abnormalities in AID have been shown to disrupt gene networks and signaling pathways in both B-cell and T-cell lineage lymphoblastic leukemia, although the full extent of its role in carcinogenesis remains unclear. This review proposes an alternative role for AID and explores its off-target effects in regulating tumorigenesis. In this review, we first provide an overview of the physiological function of AID and its regulation. AID plays a crucial role in promoting B cell diversification through SHM and CSR. We then discuss the off-target effects of AID, which includes inducing mutations of non-Igs, epigenetic modification, and the alternative role as a cofactor. We also explore the networks that keep AID in line. Furthermore, we summarize the off-target effects of AID in autoimmune diseases and hematological neoplasms. Finally, we assess the off-target effects of AID in solid tumors. The primary focus of this review is to understand how and when AID targets specific gene loci and how this affects carcinogenesis. Overall, this review aims to provide a comprehensive understanding of the physiological and off-target effects of AID, which will contribute to the development of novel therapeutic strategies for autoimmune diseases, hematological neoplasms, and solid tumors.

The Diagnostic and Prognostic Value of miR-155 in Cancers: An Updated Meta-analysis

BACKGROUND

MicroRNA-155 has been discussed as a biomarker in cancer diagnosis and prognosis. Although relevant studies have been published, the role of microRNA-155 remains uncertain because of insufficient data.

METHODS

We conducted a literature search in PubMed, Embase, and Web of Science databases to obtain relevant articles and extract data to evaluate the role of microRNA-155 in cancer diagnosis and prognosis.

RESULTS

The pooled results showed that microRNA-155 presented a remarkable diagnostic value in cancers (area under the curve = 0.90, 95% confidence interval (CI 0.87-0.92; sensitivity = 0.83, 95% CI 0.79-0.87; specificity = 0.83, 95% CI 0.80-0.86), which was maintained in the subgroups stratified by ethnicity (Asian and Caucasian), cancer types (breast cancer, lung cancer, hepatocellular carcinoma, leukemia, and pancreatic ductal adenocarcinoma), sample types (plasma, serum, tissue), and sample size (n >100 and n <100). In prognosis, a combined hazard ratio (HR) showed that microRNA-155 was significantly associated with poor overall survival (HR = 1.38, 95% CI 1.25-1.54) and recurrence-free survival (HR = 2.13, 95% CI 1.65-2.76), and was boundary significant with poor progression-free survival (HR = 1.20, 95% CI 1.00-1.44), but not significant with disease-free survival (HR = 1.14, 95% CI 0.70-1.85). Subgroup analyses in overall survival showed that microRNA-155 was associated with poor overall survival in the subgroups stratified by ethnicity and sample size. However, the significant association was maintained in cancer types subgroups of leukemia, lung cancer, and oral squamous cell carcinoma, but not in colorectal cancer, hepatocellular carcinoma, and breast cancer, and was maintained in sample types subgroups of bone marrow and tissue, but not in plasma and serum.

CONCLUSIONS

Results from this meta-analysis demonstrated that microRNA-155 was a valuable biomarker in cancer diagnosis and prognosis.

The biomarkers of key miRNAs and gene targets associated with extranodal NK/T-cell lymphoma

Gene expression profiling studies have shown the pathogenetic role of oncogenic pathways in extranodal natural killer/T-cell lymphoma (ENKL). In this study, we aimed to identify the microRNAs (miRNAs) playing potential roles in ENKL, and to evaluate the genes and biological pathways associated to them. Gene expression profiles of ENKL patients were acquired from the gene expression omnibus (GEO) database. Most differentially expressed (DE)-miRNAs were identified in ENKL patients using limma package. Gene targets of the DE-miRNAs were collected from online databases (miRDB, miRWalk, miRDIP, and TargetScan), and used in Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses on Database for annotation, visualization, and integrated discovery database, and then used in protein–protein interaction (PPI) analysis on STRING database. Hub genes of the PPI network were identified in cytoHubba, and were evaluated in Biological networks gene ontology. According to the series GSE31377 and GSE43958 from GEO database, four DE-miRNAs were screened out: hsa-miR-363-3p, hsa-miR-296-5p, hsa-miR-155-5p, and hsa-miR-221-3p. Totally 164 gene targets were collected from the online databases, and used in the GO and KEGG pathway analyses and PPI network analysis. Ten hub genes of the PPI network were identified: AURKA, TP53, CDK1, CDK2, CCNB1, PLK1, CUL1, ESR1, CDC20, and PIK3CA. Those hub genes, as well as their correlative pathways, may be of diagnostic or therapeutic potential for ENKL, but further clinical evidence is still expected.

Emerging Roles and Potential Applications of Non-Coding RNAs in Glioblastoma

Non-coding RNAs (ncRNAs) comprise a diversity of RNA species, which do not have the potential to encode proteins. Non-coding RNAs include two classes of RNAs, namely: short regulatory ncRNAs and long non-coding RNAs (lncRNAs). The short regulatory RNAs, containing up to 200 nucleotides, include small RNAs, such as microRNAs (miRNA), short interfering RNAs (siRNAs), piwi-interacting RNAs (piRNAs), and small nucleolar RNAs (snoRNAs). The lncRNAs include long antisense RNAs and long intergenic RNAs (lincRNAs). Non-coding RNAs have been implicated as master regulators of several biological processes, their expression being strictly regulated under physiological conditions. In recent years, particularly in the last decade, substantial effort has been made to investigate the function of ncRNAs in several human diseases, including cancer. Glioblastoma is the most common and aggressive type of brain cancer in adults, with deregulated expression of small and long ncRNAs having been implicated in onset, progression, invasiveness, and recurrence of this tumor. The aim of this review is to guide the reader through important aspects of miRNA and lncRNA biology, focusing on the molecular mechanism associated with the progression of this highly malignant cancer type.

Acidic leucine-rich nuclear phosphoprotein-32A expression contributes to adverse outcome in acute myeloid leukemia

Background

Acidic leucine-rich nuclear phosphoprotein-32A (ANP32A) is a novel regulator of histone H3 acetylation and promotes leukemogenesis in acute myeloid leukemia (AML). However, its prognostic value in AML remains unclear.

Methods

In this study, we evaluated the prognostic significance of ANP32A expression using two independent large cohorts of cytogenetically normal AML (CN-AML) patients. Multivariable analysis in CN-AML group was also presented. Based on the ANP32A expression, its related genes, dysregulation of pathways, interaction network analysis between microRNAs and target genes, as well as methylation analysis were performed to unveil the complex functions behind ANP32A.

Results

Here we demonstrated overexpression of ANP32A was notably associated with unfavorable outcome in two independent cohorts of CN-AML patients (OS: P=0.012, EFS: P=0.005, n=185; OS: P=0.041, n=232), as well as in European Leukemia Net (ELN) Intermediate-I group (OS: P=0.018, EFS: P=0.045, n=115), National Comprehensive Cancer Network (NCCN) Intermediate Risk AML group (OS: P=0.048, EFS: P=0.039, n=225), and non-M3 AML group (OS: P=0.034, EFS: P=0.011, n=435). Multivariable analysis further validated ANP32A as a high-risk factor in CN-AML group. Multi-omics analysis presented overexpression of ANP32A was associated with aberrant expression of oncogenes and tumor suppressor, up/down-regulation of metabolic and immune-related pathways, dysregulation of microRNAs, and hypomethylation on CpG island and 1st Exon regions.

Conclusions

We proved ANP32A as a novel, potential unfavorable prognosticator and therapeutic target for AML.

Infectious stimuli promote malignant B-cell acute lymphoblastic leukemia in the absence of AID

The prerequisite to prevent childhood B-cell acute lymphoblastic leukemia (B-ALL) is to decipher its etiology. The current model suggests that infection triggers B-ALL development through induction of activation-induced cytidine deaminase (AID; also known as AICDA) in precursor B-cells. This evidence has been largely acquired through the use of ex vivo functional studies. However, whether this mechanism governs native non-transplant B-ALL development is unknown. Here we show that, surprisingly, AID genetic deletion does not affect B-ALL development in Pax5-haploinsufficient mice prone to B-ALL upon natural infection exposure. We next test the effect of premature AID expression from earliest pro-B-cell stages in B-cell transformation. The generation of AID off-target mutagenic activity in precursor B-cells does not promote B-ALL. Likewise, known drivers of human B-ALL are not preferentially targeted by AID. Overall these results suggest that infections promote B-ALL through AID-independent mechanisms, providing evidence for a new model of childhood B-ALL development.

Infection or chronic inflammation is a risk factor for childhood B-cell precursor acute lymphoblastic leukemia. Here, the authors show that the DNA editing enzyme AID is expressed in infected B cells but using genetic mouse models show that it does not contribute to leukemia pathogenesis.

Prognostic and Clinicopathological Significance of MiR-155 in Hematologic Malignancies: A Systematic Review and Meta-analysis

Background: Aberrant miR-155 expression has been reported in various types of hematologic malignancies. However, the prognostic and clinicopathological value of miR-155 remains unclear. Here, we performed this systemic review and meta-analysis to comprehensively evaluate the prognostic and clinicopathological significance of miR-155 expression in hematologic malignancies.

Methods: We systematically searched the PubMed, EMBASE, ISI Web of Science, Cochrane library databases and OVID to identify eligible studies published from Jan 1, 2008 to Aug 1, 2018. The pooled hazard ratios (HRs) and odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to detect the prognostic and clinicopathological role of miR-155 in hematologic malignancies.

Results: A total of 18 studies including 2316 patients were enrolled in the present meta-analysis, indicating significant association between elevated miR-155 expression and poor overall survival (OS) in 2114 patients (pooled HR = 1.72, 95%CI [1.50-1.97], p<0.001). Elevated miR-155 expression level was related to shorter event free survival (EFS, pooled HR = 1.55, 95%CI [0.94-2.57], P=0.002), disease free survival (DFS, pooled HR = 1.38, 95%CI [1.13-1.68], P=0.001), progress free survival (PFS, pooled HR = 1.58, 95%CI [1.06-2.35], p<0.001) and treatment free survival (TFS, pooled HR = 1.67, 95%CI [1.16-2.39], P=0.006). Additionally, overexpression of miR-155 was found to be significantly related to FLT3/ITD presence (OR=4.751, 95%CI [3.229-6.990], P<0.001), more WT1 mutation (OR=2.090, 95%CI [1.240-3.522], P=0.006) and less CEBPA mutation (OR=0.477, 95%CI [0.286-0.794], P=0.004) in 552 AML patients.

Conclusion: MiR-155 expression was found to be associated with several leukemia-related phenotype and poor prognosis in hematologic malignancies. Therefore, miR-155 overexpression might be a convinced unfavorable prognostic indicator that helps the clinical decision-making process.