Volume 04 · Issue 03 · 2022

RNA-binding proteins (RBPs) are widely involved in the transcriptional and posttranscriptional regulation of multiple biological processes. The transcriptional regulatory ability of RBPs was indicated by the identification of chromatin-enriched RBPs (Che-RBPs). One of these proteins, KH-type splicing regulatory protein (KHSRP), is a multifunctional RBP that has been implicated in mRNA decay, alternative splicing, and miRNA biogenesis and plays an essential role in myeloid differentiation by facilitating the maturation of miR-129. In this study, we revealed that KHSRP regulates monocytic differentiation by regulating gene transcription and RNA splicing. KHSRP-occupied specific genomic sites in promoter and enhancer regions to regulate the expression of several hematopoietic genes through transcriptional activation and bound to pre-mRNA intronic regions to modulate alternative splicing during monocytic differentiation. Of note, KHSRP had co-regulatory effects at both the transcriptional and posttranscriptional levels on MOGOH and ADARB1. Taken together, our analyses revealed the dual DNA- and RNA-binding activities of KHSRP and have provided a paradigm to guide the analysis of other functional Che-RBPs in different biological systems.

N⁶-Methyladenosine (m⁶A) is the most abundant modification in eukaryotic mRNA, and plays important biological functions via regulating RNA fate determination. Recent studies have shown that m⁶A modification plays a key role in hematologic malignancies, including acute myeloid leukemia. The current growth of epitranscriptomic research mainly benefits from technological progress in detecting RNA m⁶A modification in a transcriptome-wide manner. In this review, we first briefly summarize the latest advances in RNA m⁶A biology by focusing on writers, readers, and erasers of m⁶A modification, and describe the development of high-throughput methods for RNA m⁶A mapping. We further discuss the important roles of m⁶A modifiers in acute myeloid leukemia, and highlight the identification of potential inhibitors for AML treatment by targeting of m⁶A modifiers. Overall, this review provides a comprehensive summary of RNA m⁶A biology in acute myeloid leukemia.

The maintenance of the mammalian blood system depends on hematopoietic stem cells (HSCs), which are a rare class of adult stem cells with self-renewal and multilineage differentiation capacities. The homeostasis of hematopoietic stem cells is finely tuned by a variety of endogenous and exogenous regulatory factors, and disrupted balance will lead to hematological diseases including leukemia and anemia. Recently, emerging studies have illustrated the cellular and molecular mechanisms underlying the regulation of HSC homeostasis. Particularly, the rapid development of second-generation sequencing technologies has uncovered that many small noncoding RNAs (ncRNAs) are highly expressed in HSCs, including snoRNAs, miRNAs, tsRNAs, circular RNAs, etc. In this study, we will summarize the essential roles and regulatory mechanisms of these small ncRNAs in maintaining HSC homeostasis. Overall, this review provides up-to-date information in the regulation of HSC homeostasis by small ncRNAs, which sheds light into the development of therapeutic strategies against hematopoietic malignancies.

The advent of whole-slide imaging, faster image data generation, and cheaper forms of data storage have made it easier for pathologists to manipulate digital slide images and interpret more detailed biological processes in conjunction with clinical samples. In parallel, with continuous breakthroughs in object detection, image feature extraction, image classification and image segmentation, artificial intelligence (AI) is becoming the most beneficial technology for high-throughput analysis of image data in various biomedical imaging disciplines. Integrating digital images into biological workflows, advanced algorithms, and computer vision techniques expands the biologist’s horizons beyond the microscope slide. Here, we introduce recent developments in AI applied to microscopy in hematopathology. We give an overview of its concepts and present its applications in normal or abnormal hematopoietic cells identification. We discuss how AI shows great potential to push the limits of microscopy and enhance the resolution, signal and information content of acquired data. Its shortcomings are discussed, as well as future directions for the field.

Defects in centrosomes are associated with a broad spectrum of hematological malignancies, such as leukemia and lymphoma. Centrosomes in these malignancies display both numerical and structural aberrations, including alterations in the number and size of centrioles, inappropriate post-translational modification of centrosomal proteins, and extra centrosome clustering. There is accumulating evidence that centrosome defects observed in hematological malignancies result from multiple factors, including dysregulation of the centrosome cycle and impairment of centriole biogenesis. In this review, we discuss the plausible mechanisms of centrosome defects and highlight their consequences in hematological malignancies. We also illustrate the latest therapeutic strategies against hematological malignancies by targeting centrosome anomalies.

Regulated cell death (RCD) is essential for maintaining cell homeostasis and preventing diseases. Besides classical apoptosis, several novel nonapoptotic forms of RCD including NETosis, pyroptosis, ferroptosis, and cuproptosis have been reported and are increasingly being implicated in various cancers and inflammation. Disulfiram (DSF), an aldehyde dehydrogenase inhibitor, has been used clinically for decades as an anti-alcoholic drug. New studies have shown that DSF possesses potent anti-inflammatory and anti-cancer effects by regulating these new types of RCD. Here, we summarize the mechanisms and discuss the potential application of DSF in the treatment of cancers and inflammatory diseases.

Adult T-cell lymphoblastic lymphoma (T-LBL) is a rare and aggressive subtype of non-Hodgkin’s lymphoma that differs from pediatric T-LBL and has a worse prognosis. Due to its rarity, little is known about the genetic and molecular characteristics, optimal treatment modalities, and prognostic factors of adult T-LBL. Therefore, we summarized the existing studies to comprehensively discuss the above issues in this review. Genetic mutations of NOTCH1/FBXW7, PTEN, RAS, and KMT2D, together with abnormal activation of signaling pathways, such as the JAK-STAT signaling pathway were described. We also discussed the therapeutic modalities. Once diagnosed, adult T-LBL patients should receive intensive or pediatric acute lymphoblastic leukemia regimen and central nervous system prophylaxis as soon as possible, and cranial radiation-free protocols are appropriate. Mediastinal radiotherapy improves clinical outcomes, but adverse events are of concern. Hematopoietic stem cell transplantation may be considered for adult T-LBL patients with high-risk factors or those with relapsed/refractory disease. Besides, several novel prognostic models have been constructed, such as the 5-miRNAs-based classifier, 11-gene-based classifier, and 4-CpG-based classifier, which have presented significant prognostic value in adult T-LBL.

B-cell acute lymphoblastic leukemia (B-ALL) is a malignant tumor originating from B-lineage lymphoid precursor cells. The incidence of B-ALL is about 80% in childhood acute leukemia and 20% in adults. In recent years, with standardized treatment guided by risk stratification, the long-term disease-free survival rate of children is about 80%, while that of adults is less than 40%. However, the specific pathogenesis of the newly identified B-ALL and the targeted therapy strategies have not been vigorously investigated. In this review, we highlight the recent breakthroughs in mechanistic studies and novel therapeutic options in DUX4- and MEF2D-subtype B-ALLs.