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Like almost all cancer types, timely diagnosis is needed for leukemias to be effectively cured. Drug efflux, attenuated drug uptake, altered drug metabolism, and epigenetic alterations are just several of the key mechanisms by which drug resistance develops. All of these mechanisms are orchestrated by up- and downregulators, in which non-coding RNAs (ncRNAs) do not encode specific proteins in most cases; albeit, some of them have been found to exhibit the potential for protein-coding. Notwithstanding, ncRNAs are chiefly known for their contribution to the regulation of physiological processes, as well as the pathological ones, such as cell proliferation, apoptosis, and immune responses. Specifically, in the case of leukemia chemo-resistance, ncRNAs have been recognized to be responsible for modulating the initiation and progression of drug resistance. Herein, we comprehensively reviewed the role of ncRNAs, specifically its effect on molecular mechanisms and signaling pathways, in the development of leukemia drug resistance., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Small interfering RNAs (siRNAs) have emerged as a powerful tool to manipulate gene expression in vitro . However, their potential therapeutic application encounters significant challenges, such as degradation in vivo, limited cellular uptake, and restricted biodistribution, among others. This study evaluates the siRNA delivery efficiency of three different lipid-substituted polyethylenimine (PEI)-based carriers, named Leu-Fect A-C, to different organs in vivo , including xenograft tumors, when injected into the bloodstream of mice. The siRNA analysis was undertaken by stem-loop RT-PCR, followed by qPCR or digital droplet PCR. Formulating siRNAs with a Leu-Fect series of carriers generated nanoparticles that effectively delivered the siRNAs into K652 and MV4-11 cells, both models of leukemia. The Leu-Fect carriers were able to successfully deliver BCR-Abl and FLT3 siRNAs into leukemia xenograft tumors in mice. All three carriers demonstrated significantly enhanced siRNA delivery into organs other than the liver, including the xenograft tumors. Preferential biodistribution of siRNAs was observed in the lungs and spleen. Among the delivery systems, Leu-Fect A exhibited the highest biodistribution into organs. In conclusion, lipid-substituted PEI-based delivery systems offer improvements in addressing pharmacokinetic challenges associated with siRNA-based therapies, thus opening avenues for their potential translation into clinical practice.

Cancer is a leading cause of death globally. The majority of cancer cases are only diagnosed in the late stages of cancer due to the use of conventional methods. This reduces the chance of survival for cancer patients. Therefore, early detection consequently followed by early diagnoses are important tasks in cancer research. Gene expression microarray technology has been applied to detect and diagnose most types of cancers in their early stages and has gained encouraging results. In this paper, we address the problem of classifying cancer based on gene expression for handling the class imbalance problem and the curse of dimensionality. The oversampling technique is utilized to overcome this problem by adding synthetic samples. Another common issue related to the gene expression dataset addressed in this paper is the curse of dimensionality. This problem is addressed by applying chi-square and information gain feature selection techniques. After applying these techniques individually, we proposed a method to select the most significant genes by combining those two techniques (CHiS and IG). We investigated the effect of these techniques individually and in combination. Four benchmarking biomedical datasets (Leukemia-subtypes, Leukemia-ALLAML, Colon, and CuMiDa) were used. The experimental results reveal that the oversampling techniques improve the results in most cases. Additionally, the performance of the proposed feature selection technique outperforms individual techniques in nearly all cases. In addition, this study provides an empirical study for evaluating several oversampling techniques along with ensemble-based learning. The experimental results also reveal that SVM-SMOTE, along with the random forests classifier, achieved the highest results, with a reporting accuracy of 100%. The obtained results surpass the findings in the existing literature as well.

Chromosome gains or losses often lead to copy number variations (CNV) and loss of heterozygosity (LOH). Both quantities are low in hematologic "liquid" cancers versus solid tumors in data of The Cancer Genome Atlas (TCGA) that also shows the fraction of a genome affected by LOH is ~ one-half of that with CNV. Suspension cultures of p53-null THP-1 leukemia-derived cells conform to these trends, despite novel evidence here of genetic heterogeneity and transiently elevated CNV after perturbation. Single-cell DNAseq indeed reveals at least 8 distinct THP-1 aneuploid clones with further intra-clonal variation, suggesting ongoing genetic evolution. Importantly, acute inhibition of the mitotic spindle assembly checkpoint (SAC) produces CNV levels that are typical of high-CNV solid tumors, with subsequent cell death and down-selection to novel CNV. Pan-cancer analyses show p53 inactivation associates with aneuploidy, but leukemias exhibit a weaker trend even though p53 inactivation correlates with poor survival. Overexpression of p53 in THP-1 does not rescue established aneuploidy or LOH but slightly increases cell death under oxidative or confinement stress, and triggers p21, a key p53 target, but without affecting net growth. Our results suggest that factors other than p53 exert stronger pressures against aneuploidy in liquid cancers, and identifying such CNV suppressors could be useful across liquid and solid tumor types., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Dysregulated cholesterol homeostasis promotes tumorigenesis and progression. Therefore, metabolic reprogramming constitutes a new hallmark of cancer. However, until today, only few therapeutic approaches exist to target this pathway due to the often-observed negative feedback induced by agents like statins leading to controversially increased cholesterol synthesis upon inhibition. Sterol regulatory element-binding proteins (SREBPs) are key transcription factors regulating the synthesis of cholesterol and fatty acids. Since SREBP2 is difficult to target, we performed pharmacological inhibition of retinoic acid receptor (RAR)-related orphan receptor gamma (RORγ), which acts upstream of SREBP2 and serves as master regulator of the cholesterol metabolism. This resulted in an inactivated cholesterol-related gene program with significant downregulation of cholesterol biosynthesis. Strikingly, these effects were more pronounced than the effects of fatostatin, a direct SREBP2 inhibitor. Upon RORγ inhibition, RNA sequencing showed strongly increased cholesterol efflux genes leading to leukemic cell death and cell cycle changes in a dose- and time-dependent manner. Combinatorial treatment of t(4;11) cells with the RORγ inhibitor showed additive effects with cytarabine and even strong anti-leukemia synergism with atorvastatin by circumventing the statin-induced feedback. Our results suggest a novel therapeutic strategy to inhibit tumor-specific cholesterol metabolism for the treatment of t(4;11) leukemia., (© 2023. The Author(s).)

Leukemia is cancer of the body's blood-forming tissues, including the bone marrow and the lymphatic system. There are many types of leukemia that some of them occur in children and the others are more common in adults. Currently, there are many different chemotherapy agents for leukemia while chemoresistance increases the survival of the leukemic cells. One of the main reasons of chemoresistance, is a transcription factor called Nuclear factor erythroid 2-Related Factor 2 (NRF2). An increase in NRF2 expression in leukemic cells which are being treated with chemotherapy agents, can increase the survival of these cells in the presence of therapeutics. Accordingly, the inhibition of NRF2 by different methods as a cotreatment with classical chemotherapy agents, can be a promising procedure in leukemia treatment. In this study we focus on the association of NRF2 and leukemia and targeting it as a new therapeutic method in leukemia treatment., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

MicroRNAs (miRNAs) are short noncoding RNAs, approximately 20-24 nucleotides long that negatively regulate gene expression by either inhibiting translation or cleaving complementary mRNA to participate in various biological processes. Accumulating evidence has indicated that miRNAs are widely present in hematological cancers, particularly leukemia, exhibiting either upregulation or downregulation in leukemia patients compared with healthy controls. These miRNAs have a pivotal role in the development, progression and metastasis of leukemia, as well as in the prognosis and/or relapse of patients. miR-22 is one of the abnormally expressed miRNAs in a variety of leukemia diseases, and is considered to be one of the few cancer suppressors. Recent research has demonstrated that miR-22 is involved in the regulation of leukemia cell proliferation, differentiation and apoptosis, and could be a promising biomarker and prognostic indicator for leukemia. Here, we summarize all relevant findings that carry out experimental investigation and clinical analyses, aiming to elucidate the comprehensive implications of miR-22 in various types of leukemia for the development of new therapeutic and prognostic strategies and new drug targets for the treatment of leukemia., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

A common mRNA modification is 5-methylcytosine (m 5 C), whose role in gene-transcript processing and cancer remains unclear. Here, we identify serine/arginine-rich splicing factor 2 (SRSF2) as a reader of m 5 C and impaired SRSF2 m 5 C binding as a potential contributor to leukemogenesis. Structurally, we identify residues involved in m 5 C recognition and the impact of the prevalent leukemia-associated mutation SRSF2 P95H . We show that SRSF2 binding and m 5 C colocalize within transcripts. Furthermore, knocking down the m 5 C writer NSUN2 decreases mRNA m 5 C, reduces SRSF2 binding, and alters RNA splicing. We also show that the SRSF2 P95H mutation impairs the ability of the protein to read m 5 C-marked mRNA, notably reducing its binding to key leukemia-related transcripts in leukemic cells. In leukemia patients, low NSUN2 expression leads to mRNA m 5 C hypomethylation and, combined with SRSF2 P95H , predicts poor outcomes. Altogether, we highlight an unrecognized mechanistic link between epitranscriptomics and a key oncogenesis driver., Competing Interests: Declaration of interests F.F. is a co-founder of Epics Therapeutics (Gosselies, Belgium)., (Copyright © 2023 Elsevier Inc. All rights reserved.)

HSP90 has emerged as an appealing anti-cancer target. However, HSP90 inhibitors (HSP90i) are characterized by limited clinical utility, primarily due to the resistance acquisition via heat shock response (HSR) induction. Understanding the roles of abundantly expressed cytosolic HSP90 isoforms (α and β) in sustaining malignant cells' growth and the mechanisms of resistance to HSP90i is crucial for exploiting their clinical potential. Utilizing multi-omics approaches, we identified that ablation of the HSP90β isoform induces the overexpression of HSP90α and extracellular-secreted HSP90α (eHSP90α). Notably, we found that the absence of HSP90α causes downregulation of PTPRC (or CD45) expression and restricts in vivo growth of BCR-ABL1+ leukemia cells. Subsequently, chronic long-term exposure to the clinically advanced HSP90i PU-H71 (Zelavespib) led to copy number gain and mutation (p.S164F) of the HSP90AA1 gene, and HSP90α overexpression. In contrast, acquired resistance toward other tested HSP90i (Tanespimycin and Coumermycin A1) was attained by MDR1 efflux pump overexpression. Remarkably, combined CDK7 and HSP90 inhibition display synergistic activity against therapy-resistant BCR-ABL1+ patient leukemia cells via blocking pro-survival HSR and HSP90α overexpression, providing a novel strategy to avoid the emergence of resistance against treatment with HSP90i alone., (© 2023. The Author(s).)

Epigenetic dysregulation, particularly alterations in DNA methylation and hydroxymethylation, plays a pivotal role in cancer initiation and progression. Ten-eleven translocation (TET) proteins catalyze the successive oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and further oxidized methylcytosines in DNA, thereby serving as central modulators of DNA methylation-demethylation dynamics. TET loss of function is causally related to neoplastic transformation across various cell types while its genetic or pharmacological activation exhibits anti-cancer effects, making TET proteins promising targets for epigenetic cancer therapy. Here, we developed a robust cell-based screening system to identify novel TET activators and evaluated their potential as anti-cancer agents. Using a carefully curated library of 4533 compounds provided by the National Cancer Institute, Bethesda, MD, USA, we identified mitoxantrone as a potent TET agonist. Through rigorous validation employing various assays, including immunohistochemistry and dot blot studies, we demonstrated that mitoxantrone significantly elevated 5hmC levels. Notably, this elevation manifested only in wild-type (WT) but not TET-deficient mouse embryonic fibroblasts, primary bone marrow-derived macrophages, and leukemia cell lines. Furthermore, mitoxantrone-induced cell death in leukemia cell lines occurred in a TET-dependent manner, indicating the critical role of TET proteins in mediating its anti-cancer effects. Our findings highlight mitoxantrone's potential to induce tumor cell death via a novel mechanism involving the restoration of TET activity, paving the way for targeted epigenetic therapies in cancer treatment.

Nuclear deformability plays a critical role in cell migration. During this process, the remodeling of internal components of the nucleus has a direct impact on DNA damage and cell behavior; however, how persistent migration promotes nuclear changes leading to phenotypical and functional consequences remains poorly understood. Here, we described that the persistent migration through physical barriers was sufficient to promote permanent modifications in migratory-altered cells. We found that derived cells from confined migration showed changes in lamin B1 localization, cell morphology and transcription. Further analysis confirmed that migratory-altered cells showed functional differences in DNA repair, cell response to chemotherapy and cell migration in vivo homing experiments. Experimental modulation of actin polymerization affected the redistribution of lamin B1, and the basal levels of DNA damage in migratory-altered cells. Finally, since major nuclear changes were present in migratory-altered cells, we applied a multidisciplinary biochemical and biophysical approach to identify that confined conditions promoted a different biomechanical response of the nucleus in migratory-altered cells. Our observations suggest that mechanical compression during persistent cell migration has a role in stable nuclear and genomic alterations that might handle the genetic instability and cellular heterogeneity in aging diseases and cancer., (© 2023. The Author(s).)

Erythropoietin (EPO) suppresses drug-induced apoptosis in EPO-receptor-positive leukemia cells and allows cells to persist after drug treatment by promoting cellular senescence. Importantly a small proportion of senescent cells can re-enter the cell cycle and resume proliferation after drug treatment, resulting in disease recurrence/persistence. Using a single-cell assay to track individual cells that exit a drug-induced senescence-like state, we show that cells exhibit asynchronous exit from a senescent-like state, and display different rates of proliferation. Escaped cells retain sensitivity to drug treatment, but display inter-clonal variability. We also find heterogeneity in gene expression with some of the escaped clones retaining senescence-associated gene expression. Senescent leukemia cells exhibit changes in gene expression that affect metabolism and senescence-associated secretory phenotype (SASP)-related genes. Herein, we generate a senescence gene signature and show that this signature is a prognostic marker of worse overall survival in AML and multiple other cancers. A portion of senescent leukemia cells depend on lysosome activity; chloroquine, an inhibitor of lysosome activity, promotes senolysis of some senescent leukemia cells. Our study indicates that the serious risks associated with the use of erythropoietin-stimulating agents (ESAs) in anemic cancer patients may be attributed to their ability to promote drug-tolerant cancer cells through the senescence program., (© 2023. The Author(s).)

The epithelial to mesenchymal transition (EMT) is a fundamental developmental process essential for normal embryonic development. It is also important during various pathogenic processes including fibrosis, wound healing and epithelial cancer cell metastasis and invasion. EMT is regulated by a variety of cell signalling pathways, cell-cell interactions and microenvironmental cues, however the key drivers of EMT are transcription factors of the ZEB, TWIST and SNAIL families. Recently, novel and unexpected roles for these EMT transcription factors (EMT-TFs) during normal blood cell development have emerged, which appear to be largely independent of classical EMT processes. Furthermore, EMT-TFs have also begun to be implicated in the development and pathogenesis of malignant hematological diseases such as leukemia and lymphoma, and now present themselves or the pathways they regulate as possible new therapeutic targets within these malignancies. In this review, we discuss the ZEB, TWIST and SNAIL families of EMT-TFs, focusing on what is known about their normal roles during hematopoiesis as well as the emerging and "unexpected" contribution they play during development and progression of blood cancers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Radhakrishnan, Truong and Carmichael.)

Manufacturing chimeric antigen receptor (CAR)-T cells using viral vectors is expensive and time-consuming. In addition, during viral transduction, genes encoding CARs are randomly integrated into the genome, which can cause oncogenesis or produce devastating CAR-tumor cells. Here, using a virus-free and non-transgenic minicircle DNA (mcDNA) vector, we enabled the rapid generation of CD19 CAR-T cells within two days. Furthermore, we demonstrated in vitro and in xenograft models that the antitumor effects of CD19 CAR-T cells produced by mcDNA are as effective as those produced by viral vectors. Finally, we showed that our manufacturing process avoids the production of fatal CAR-tumor cells. Taken together, we have provided a fast, effective, and therapeutically safe method for generating CD19 CAR-T cells for the treatment of leukemia., Competing Interests: Declaration of competing interest All authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Leukemia is a group of highly heterogeneous and life-threatening blood cancers that originate from abnormal hematopoietic stem cells. Multiple treatments are approved for leukemia, including chemotherapy, targeted therapy, hematopoietic stem cell transplantation, radiation therapy, and immunotherapy. Unfortunately, therapeutic resistance occurs in a substantial proportion of patients and greatly compromises the treatment efficacy of leukemia, resulting in relapse and mortality. The abnormal activity of receptor tyrosine kinases, cell membrane transporters, intracellular signal transducers, transcription factors, and anti-apoptotic proteins have been shown to contribute to the emergence of therapeutic resistance. Despite these findings, the exact mechanisms of treatment resistance are still not fully understood, which limits the development of effective measures to overcome it. Long non-coding RNAs (lncRNA) are a class of regulatory molecules that are gaining increasing attention, and lncRNA-mediated regulation of therapeutic resistance against multiple drugs for leukemia is being revealed. These dysregulated lncRNAs not only serve as potential targets to reduce resistance but also might improve treatment response prediction and individualized treatment decision. Here, we summarize the recent findings on lncRNA-mediated regulation of therapeutic resistance in leukemia and discuss future perspectives on how to make use of the dysregulated lncRNAs in leukemia to improve treatment outcome., (© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Somatic structural variants (SVs) are widespread in cancer, but their impact on disease evolution is understudied due to a lack of methods to directly characterize their functional consequences. We present a computational method, scNOVA, which uses Strand-seq to perform haplotype-aware integration of SV discovery and molecular phenotyping in single cells by using nucleosome occupancy to infer gene expression as a readout. Application to leukemias and cell lines identifies local effects of copy-balanced rearrangements on gene deregulation, and consequences of SVs on aberrant signaling pathways in subclones. We discovered distinct SV subclones with dysregulated Wnt signaling in a chronic lymphocytic leukemia patient. We further uncovered the consequences of subclonal chromothripsis in T cell acute lymphoblastic leukemia, which revealed c-Myb activation, enrichment of a primitive cell state and informed successful targeting of the subclone in cell culture, using a Notch inhibitor. By directly linking SVs to their functional effects, scNOVA enables systematic single-cell multiomic studies of structural variation in heterogeneous cell populations., (© 2022. The Author(s).)

The molecular regulation of human hematopoietic stem cell (HSC) maintenance is therapeutically important, but limitations in experimental systems and interspecies variation have constrained our knowledge of this process. Here, we have studied a rare genetic disorder due to MECOM haploinsufficiency, characterized by an early-onset absence of HSCs in vivo. By generating a faithful model of this disorder in primary human HSCs and coupling functional studies with integrative single-cell genomic analyses, we uncover a key transcriptional network involving hundreds of genes that is required for HSC maintenance. Through our analyses, we nominate cooperating transcriptional regulators and identify how MECOM prevents the CTCF-dependent genome reorganization that occurs as HSCs differentiate. We show that this transcriptional network is co-opted in high-risk leukemias, thereby enabling these cancers to acquire stem cell properties. Collectively, we illuminate a regulatory network necessary for HSC self-renewal through the study of a rare experiment of nature., (© 2022. The Author(s).)

Leukemia is a type of cancer that affects white blood cells. In this disease, immature blood cells undergo genetic mutations, leading to excessive replication and reduced cell death compared to healthy cells. In cancer, there may be the activation of oncogenes and the deactivation of tumor suppressor genes that control certain cellular functions. Despite the undeniable contribution to the patient's recovery, conventional cancer treatments may have some not-so-beneficial effects. In this case, gene therapy appears as an alternative to classical treatments. Gene therapy delivers genetic material to cells to replace or modify dysfunctional genes, a safe method for neoplasms. One of the types of nucleic acids explored in gene therapy is microRNA (miRNA), a group of endogenous, non-proteincoding, small single-stranded RNA molecules involved in the regulation of gene expression, cell division, differentiation, angiogenesis, migration, apoptosis, and carcinogenesis. This review aims to bring together the most recent advances found in the literature on cancer gene therapy based on microRNAs in the oncological context, focusing on leukemia., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: The pathogenesis of leukemia is complex and there are no effective diagnostic and prognostic indicators. Previous studies showed that microRNA-22 (miR-22) has altered expression level in multiple leukemia subtypes, which is associated with the survival outcomes of leukemia. Methods: According to the constituted retrieval strategy, eligible studies were included from January 2010 to November 2022 by searching database. The pooled Risk Ratio (RR) and 95% confidence intervals (CI) were used to study the relationship between miR-22 and survival. Stata12.0 was used for meta-analysis. Differential expression analysis was conducted based on expression profile of miRNA. Results: Four English articles were included containing a total of 215 leukemia patients. Data showed that the pooled RR for overall survival (OS) was 1.558 (95% CI: 1.197-2.028, P  < .01). Subgroup analysis for OS of acute myeloid leukemia patients and the RFS of plasma cell leukemia patients were statistically significant with different expression levels of miR-22 (RR:1.495, 95%CI:1.141-1.958, P  < .01 and RR:1.517, 95%CI:1.114-2.065, P  < .01, respectively). Moreover, all data included had no significant heterogeneity and publication bias. Conclusions: miR-22 is associated with the survival outcome of leukemia patients suggesting that miR-22 may be a promising prognostic biomarker for this patient population, and the expression level of miR-22 in ALL patients down-regulated., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Leukemia is a type of blood cancer characterized by high genetic heterogeneity and fatality. While chemotherapy remains the primary form of treatment for leukemia, its effectiveness was profoundly diminished by the genetic heterogeneity and cytogenetic abnormalities of leukemic cells. Therefore, there is an unmet need to develop precision medicine for leukemia with distinct genetic backgrounds. Zebrafish (Danio rerio), a freshwater fish with exceptional feasibility in genome editing, is a powerful tool for rapid human cancer modeling. In the past decades, zebrafish have been adopted in modeling human leukemia, exploring the molecular mechanisms of underlying genetic abnormalities, and discovering novel therapeutic agents. Although many recurrent mutations of leukemia have been modeled in zebrafish for pathological study and drug discovery, its great potential in leukemia modeling was not yet fully exploited, particularly in precision medicine. In this review, we evaluated the current zebrafish models of leukemia/pre-leukemia and genetic techniques and discussed the potential of zebrafish models with novel techniques, which may contribute to the development of zebrafish as a disease model for precision medicine in treating leukemia., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Myeloperoxidase (MPO) gene alterations with variable clinical penetrance have been found in hereditary MPO deficiency, but their leukemia association in patients and carriers has not been established. Germline MPO alterations were found to be significantly enriched in myeloid neoplasms: 28 pathogenic/likely pathogenic variants were identified in 100 patients. The most common alterations were c.2031-2 A > C, R569W, M519fs* and Y173C accounting for about half of the cases. While functional experiments showed that the marrow stem cell pool of Mpo -/- mice was not increased, using competitive repopulation demonstrated that Mpo -/- grafts gained growth advantage over MPO wild type cells. This finding also correlated with increased clonogenic potential after serial replating in the setting of H 2 O 2 -induced oxidative stress. Furthermore, we demonstrated that H 2 O 2 -induced DNA damage and activation of error-prone DNA repair may result in secondary genetic damage potentially predisposing to leukemia leukemic evolution. In conclusion, our study for the first time demonstrates that germline MPO variants may constitute risk alleles for MN evolution., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

The circadian clock (CC) is a daily system that regulates the oscillations of physiological processes and can respond to the external environment in order to maintain internal homeostasis. For the functioning of the CC, the clock genes (CG) act in different metabolic pathways through the clock-controlled genes (CCG), providing cellular regulation. The CC's interruption can result in the development of different diseases, such as neurodegenerative and metabolic disorders, as well as cancer. Leukemias correspond to a group of malignancies of the blood and bone marrow that occur when alterations in normal cellular regulatory processes cause the uncontrolled proliferation of hematopoietic stem cells. This review aimed to associate a deregulated CC with the manifestation of leukemia, looking for possible pathways involving CG and their possible role as leukemic biomarkers.

The contribution of natural killer (NK) cells to tumor rejection in the context of programmed death-ligand 1/programmed death 1 (PD-L1/PD-1) blockade is a matter of intense debate. To elucidate the role of PD-L1 expression on tumor cells and the functional consequences of engaging PD-1 receptor on cytotoxic cells, PD-L1 expression was genetically inactivated and WT or PD-L1-deficient parental tumor cells were adoptively transferred intravenously into F1 recipients. The engraftment of PD-L1-deficient A20 tumor cells in the spleen and liver of F1 recipients was impaired compared with A20 PD-L1 WT tumor counterparts. To elucidate the mechanism responsible for this differential tumor engraftment and determine the relevance of the role of the PD-L1/PD-1 pathway in the interplay of tumor cells/NK cells, a short-term competitive tumor implantation assay in the peritoneal cavity of semiallogeneic F1 recipients was designed. The results presented herein showed that NK cells killed target tumor cells with similar efficiency regardless of PD-L1 expression, whereas PD-L1 expression on A20 tumor cells conferred significant tumor protection against rejection by CD8 T cells confirming the role of the co-inhibitory receptor PD-1 in the modulation of their cytotoxic activity. In summary, PD-L1 expression on A20 leukemia tumor cells modulates CD8 T-cell-mediated responses to tumor-specific antigens but does not contribute to inhibit NK cell-mediated hybrid resistance, which correlates with the inability to detect PD-1 expression on NK cells neither under steady-state conditions nor under inflammatory conditions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 del Rio, Perez-Simon and Rodriguez-Barbosa.)

One of the major reasons of mortality in human beings is cancer, and there is an absolute necessity for doctors to identify and treat a person suffering from it. Leukemia is a group of blood cancers that usually originates in the bone marrow and results in very high number of abnormal cells. For the diagnosis of cancer, microarray data serves as an important clinical application and serves as a great aid to the entire medical community. The dimensionality of the microarray data is too high, and so selection of suitable genes is quite an important step for the improvement of data classification. Therefore, for the prediction and diagnosis of cancer, there is an utmost necessity to select the most informative genes. In this work, Minimum Redundancy Maximum Relevance (MRMR), Signal to Noise Ratio (SNR), Multivariate Error Weight Uncorrelated Shrunken Centroid (EWUSC), and multivariate correlation-based feature selection (CFS) are chosen as initial feature selection techniques. Then, to select the most informative genes, five different kinds of evolutionary optimization techniques too are incorporated here such as African Buffalo Optimization (ABO), Artificial Bee Colony Optimization (ABCO), Cockroach Swarm Optimization (CSO), Imperialist Competitive Optimization (ICO), and Social Spider Optimization (SSO). Finally, the optimized values are fed through classification process and the best results are obtained when multivariate CFS with SSO is utilized and classified with Probabilistic Neural Network (PNN), and a high classification accuracy of 95.70% is obtained., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Sunil Kumar Prabhakar et al.)

MicroRNAs (miRNAs) are evolutionarily conserved small non-coding RNAs, that are involved in the multistep process of carcinogenesis, contributing to all established hallmarks of cancer. In this review, implications of miRNAs in hematological malignancies and their clinical utilization fields are discussed. As components of the complex regulatory network of gene expression, influenced by the tissue microenvironment and epigenetic modifiers, miRNAs are "micromanagers" of all physiological processes including the regulation of hematopoiesis and metabolic pathways. Dysregulated miRNA expression levels contribute to both the initiation and progression of acute leukemias, the metabolic reprogramming of malignantly transformed hematopoietic precursors, and to the development of chemoresistance. Since they are highly stable and can be easily quantified in body fluids and tissue specimens, miRNAs are promising biomarkers for the early detection of hematological malignancies. Besides novel opportunities for differential diagnosis, miRNAs can contribute to advanced chemoresistance prediction and prognostic stratification of acute leukemias. Synthetic oligonucleotides and delivery vehicles aim the therapeutic modulation of miRNA expression levels. However, major challenges such as efficient delivery to specific locations, differences of miRNA expression patterns between pediatric and adult hematological malignancies, and potential side effects of miRNA-based therapies should be considered.

Cancer diagnosis based on gene expression profile data has attracted extensive attention in computational biology and medicine. It suffers from three challenges in practical applications: noise, gene grouping, and adaptive gene selection. This paper aims to solve the above problems by developing the logistic regression with adaptive sparse group lasso penalty (LR-ASGL). A noise information processing method for cancer gene expression profile data is first presented via robust principal component analysis. Genes are then divided into groups by performing weighted gene co-expression network analysis on the clean matrix. By approximating the relative value of the noise size, gene reliability criterion and robust evaluation criterion are proposed. Finally, LR-ASGL is presented for simultaneous cancer diagnosis and adaptive gene selection. The performance of the proposed method is compared with the other four methods in three simulation settings: Gaussian noise, uniformly distributed noise, and mixed noise. The acute leukemia data are adopted as an experimental example to demonstrate the advantages of LR-ASGL in prediction and gene selection., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Recent advances in comprehensive genome analysis have contributed to the discovery of several leukemia-related genes; however, the role of mutated genes in the pathogenesis of leukemia remains unknown. Clustered regularly interspaced short palindromic repeats-associated nuclease 9 (CRISPR-Cas9) technology is a powerful tool for genome-wide editing in both coding and noncoding regions. CRISPR screening has enabled high-throughput validation of gene function in diverse tumor processes, including tumor growth and survival, synthetic lethal interactions, therapeutic resistance, and response to immunotherapy, and is actively used in leukemia research. Herein, we discuss recent advances in CRISPR screening in cancer research, focusing on leukemia, and outline application strategies and prospects for CRISPR screening.

Long noncoding RNAs (lncRNAs) are a class of RNA molecules that are greater than 200 nt in length and do not have protein-coding capabilities or encode micropeptides only. LncRNAs are involved in the regulation of cell proliferation, differentiation, apoptosis and other biological processes, and are closely associated with the occurrence, recurrence and metastasis of a variety of malignant hematologic diseases. This article summarizes the function, regulatory mechanism and potential clinical application of lncRNAs in leukemia. In general, lncRNAs regulate the occurrence and development of leukemia and the multi-drug resistance in chemotherapy through epigenetic modification, ribosomal RNA transcription, competitive binding with miRNA, modulating glucose metabolic pathway, and activating tumor-related signaling pathway. Studies on lncRNAs provide new references for understanding the pathogenesis of leukemia, uncovering new prognostic markers and potential therapeutic targets, and addressing the problems of drug resistance and post-treatment recurrence in patients in clinical treatment of leukemia.

In view of the challenges of the group Lasso penalty methods for multicancer microarray data analysis, e.g., dividing genes into groups in advance and biological interpretability, we propose a robust adaptive multinomial regression with sparse group Lasso penalty (RAMRSGL) model. By adopting the overlapping clustering strategy, affinity propagation clustering is employed to obtain each cancer gene subtype, which explores the group structure of each cancer subtype and merges the groups of all subtypes. In addition, the data-driven weights based on noise are added to the sparse group Lasso penalty, combining with the multinomial log-likelihood function to perform multiclassification and adaptive group gene selection simultaneously. The experimental results on acute leukemia data verify the effectiveness of the proposed method., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2021 Lei Wang et al.)

Neoantigens are prime targets for cancer immunotherapy, but their identification in low mutational burden malignancies remains challenging. In this issue of Immunity, Ehx et al. show that atypical transcripts, and particularly retained introns, expand the spectrum of leukemia immunotherapy targets., Competing Interests: Declaration of interests C.J.W. is an equity holder of BioNTech and receives research funding from Pharmacyclics. C.J.W. has filed patent applications on personalized cancer vaccines entitled as follows: “Compositions and methods for personalized neoplasia vaccines,” “Methods for identifying tumor specific neo-antigens,” and “Combination therapy for neoantigen vaccine.” N.C. has no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Acute megakaryoblastic leukemia (AMKL) is a rare subtype of acute myeloid leukemia but is approximately 500 times more likely to develop in children with Down syndrome (DS) through transformation of transient abnormal myelopoiesis (TAM). This study investigates the clinical significance of genomic heterogeneity of AMKL in children with and without DS and in children with TAM. Genomic evaluation of nine patients with DS-related TAM or AMKL, and six patients with non-DS AMKL, included conventional cytogenetics and a comprehensive next-generation sequencing panel for single-nucleotide variants/indels and copy-number variants in 118 genes and fusions involving 110 genes. Recurrent gene fusions were found in all patients with non-DS, including two individuals with complex genomes and either a NUP98-KDM5A or a KMT2A - MLLT6 fusion, and the remaining harbored a CBFA2T3-GLIS2 fusion, which arose from both typical and atypical cytogenetic mechanisms. These fusions guided treatment protocols and resulted in a change in diagnosis in two patients. The nine patients with DS had constitutional trisomy 21 and somatic GATA1 mutations, and those with DS-AMKL had two to four additional clinically significant somatic mutations. Comprehensive genomic characterization provides critical information for diagnosis, risk stratification, and treatment decisions for patients with AMKL. Continued genetic and clinical characterization of these rare cancers will aid in improving patient management., (© 2021 Lalonde et al.; Published by Cold Spring Harbor Laboratory Press.)

Cancer is one amongst the major causes of death today and cancer biology is one of the most well researched fields in medicine. The driving force behind cancer is considered to be a minor subpopulation of cells, the cancer stem cells (CSCs). Similar to other stem cells, these cells are self-renewing and proliferating but CSCs are also difficult to target by chemo- or radio-therapies. Cancer stem cells are known to be present in most of the cancer subgroups such as carcinoma, sarcoma, myeloma, leukemia, lymphomas and mixed cancer types. There is a wide gamut of factors attributed to the stemness of cancers, ranging from dysregulated signaling pathways, and activation of enzymes aiding immune evasion, to conducive tumor microenvironment, to name a few. The defining outcome of the increased presence of CSCs is tumor metastasis and relapse. Predictive medicine approach based on the plethora of CSC markers would be a move towards precision medicine to specifically identify CSC-rich tumors. In this review, we discuss the cancer subtypes and the role of different CSC specific markers in these varying subtypes. We also categorize the CSC markers based their defining trait contributing to stemness. This review thus provides a comprehensive approach to catalogue a predictive set of markers to identify the resistant and refractory cancer stem cell population within different tumor subtypes, so as to facilitate better prognosis and targeted therapeutic strategies., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Recurrence is a primary cause of death in patients with leukemia. The interactions of tumor cells with the microenvironment and tumor stem cells hidden in bone marrow promote the recurrence and metastasis of leukemia to lymphoid tissue. Exosomes, membrane-coated nanovesicles secreted by living cells, perform biomaterial transfer and information exchange between cells. Exosomes contain various other biological components derived from parental cells, and they remotely regulate the function of target cells through body fluid flow. Recent studies revealed that exosomes participate in the development of leukemia and play important roles in its diagnosis and treatment by influencing cell proliferation and apoptosis, regulating bone marrow microenvironment, promoting angiogenesis, and inhibiting hematopoiesis. Exosomes are potential biomarkers and therapeutic targets for leukemia, and they can influence drug resistance. Leukemia-derived exosomes present leukemia-related antigens to target cells, promote the proliferation of leukemic cells, help these cells escape immunity, protect them from the cytotoxic effects of chemotherapeutics, and promote angiogenesis and tumor migration. Therefore, exosomes are closely related to the metastasis, treatment, and prognosis of leukemia, and they can be used to detect and monitor the progression of leukemia. This paper reviews the regulatory roles of exosomes in leukemia and their clinical significance.

Purpose of Review: Altered epigenetics is central to oncogenesis in many pediatric cancers. Aberrant epigenetic states are induced by mutations in histones or epigenetic regulatory genes, aberrant expression of genes regulating chromatin complexes, altered DNA methylation patterns, or dysregulated expression of noncoding RNAs. Developmental contexts of dysregulated epigenetic states are equally important for initiation and progression of many childhood cancers. As an improved understanding of disease-specific roles and molecular consequences of epigenetic alterations in oncogenesis is emerging, targeting these mechanisms of disease in childhood cancers is increasingly becoming important., Recent Findings: In addition to disease-causing epigenetic events, DNA methylation patterns and specific oncohistone mutations are being utilized for the diagnosis of pediatric central nervous system (CNS) and solid tumors. These discoveries have improved the classification of poorly differentiated tumors and laid the foundation for future improved clinical management. On the therapeutic side, the first therapies targeting epigenetic alterations have recently entered clinical trials. Current clinical trials include pharmacological inhibition of histone and DNA modifiers in aggressive types of pediatric cancer., Summary: Targeting novel epigenetic vulnerabilities, either by themselves, or coupled with targeting altered transcriptional states, developmental cell states or immunomodulation will result in innovative approaches for treating deadly pediatric cancers.

DNA microarray datasets are characterized by a large number of features with very few samples, which is a typical cause of overfitting and poor generalization in the classification task. Here, we introduce a novel feature selection (FS) approach which employs the distance correlation (dCor) as a criterion for evaluating the dependence of the class on a given feature subset. The dCor index provides a reliable dependence measure among random vectors of arbitrary dimension, without any assumption on their distribution. Moreover, it is sensitive to the presence of redundant terms. The proposed FS method is based on a probabilistic representation of the feature subset model, which is progressively refined by a repeated process of model extraction and evaluation. A key element of the approach is a distributed optimization scheme based on a vertical partitioning of the dataset, which alleviates the negative effects of its unbalanced dimensions. The proposed method has been tested on several microarray datasets, resulting in quite compact and accurate models obtained at a reasonable computational cost.

While limited observational evidence suggests that cancer survivors have a decreased risk of developing Alzheimer's disease (AD), and vice versa, it is not clear whether this relationship is causal. Using a Mendelian randomization approach that provides evidence of causality, we found that genetically predicted lung cancer (OR 0.91, 95% CI 0.84-0.99, p = 0.019), leukemia (OR 0.98, 95% CI 0.96-0.995, p = 0.012), and breast cancer (OR 0.94, 95% CI 0.89-0.99, p = 0.028) were associated with 9.0%, 2.4%, and 5.9% lower odds of AD, respectively, per 1-unit higher log odds of cancer. When genetic predictors of all cancers were pooled, cancer was associated with 2.5% lower odds of AD (OR 0.98, 95% CI 0.96-0.988, p = 0.00027) per 1-unit higher log odds of cancer. Finally, genetically predicted smoking-related cancers showed a more robust inverse association with AD than non-smoking related cancers (OR 0.95, 95% CI 0.92-0.98, p = 0.0026, vs. OR 0.98, 95% CI 0.97-0.995, p = 0.0091).

Accumulating studies have shown that long non-coding RNAs (lncRNAs) are involved in many biological processes and play important roles in a variety of complex human diseases. Developing effective computational models to identify potential relationships between lncRNAs and diseases can not only help us understand disease mechanisms at the lncRNA molecular level, but also promote the diagnosis, treatment, prognosis, and prevention of human diseases. For this paper, a network-based model called NBLDA was proposed to discover potential lncRNA⁻disease associations, in which two novel lncRNA⁻disease weighted networks were constructed. They were first based on known lncRNA⁻disease associations and topological similarity of the lncRNA⁻disease association network, and then an lncRNA⁻lncRNA weighted matrix and a disease⁻disease weighted matrix were obtained based on a resource allocation strategy of unequal allocation and unbiased consistence. Finally, a label propagation algorithm was applied to predict associated lncRNAs for the investigated diseases. Moreover, in order to estimate the prediction performance of NBLDA, the framework of leave-one-out cross validation (LOOCV) was implemented on NBLDA, and simulation results showed that NBLDA can achieve reliable areas under the ROC curve (AUCs) of 0.8846, 0.8273, and 0.8075 in three known lncRNA⁻disease association datasets downloaded from the lncRNADisease database, respectively. Furthermore, in case studies of lung cancer, leukemia, and colorectal cancer, simulation results demonstrated that NBLDA can be a powerful tool for identifying potential lncRNA⁻disease associations as well.

A balanced robertsonian translocation (rob) results from fusion of 2 acrocentric chromosomes. Carriers are phenotypically normal and are often diagnosed because of recurrent miscarriages, infertility, or aneuploid offspring. Mortality and site-specific cancer risks in carriers have not been prospectively investigated. We followed 1,987 carriers diagnosed in Great Britain for deaths and cancer risk, over an average of 24.1 years. Standardized mortality and incidence ratios were calculated comparing the number of observed events against population rates. Overall mortality was higher for carriers diagnosed before age 15 years (standardized mortality ratio (SMR) = 2.00, 95% confidence interval (CI): 1.09, 3.35), similar for those diagnosed aged 15-44 years (SMR = 1.06, 95% CI: 0.86-1.28), and lower for those diagnosed aged 45-84 years (SMR = 0.81, 95% CI: 0.68, 0.95). Cancer incidence was higher for non-Hodgkin lymphoma (standardized incidence ratio (SIR) = 1.90, 95% CI: 1.01, 3.24) and childhood leukemia (SIR = 14.5, 95% CI: 1.75, 52.2), the latter particularly in rob(15;21) carriers (SIR = 447.8, 95% CI: 11.3, 2,495). Rob(13;14) carriers had a higher breast cancer risk (SIR = 1.58, 95% CI: 1.12, 2.15). Mortality risks relative to the population in diagnosed carriers depend on age at cytogenetic diagnosis, possibly reflecting age-specific cytogenetic referral reasons. Carriers might be at greater risk of childhood leukemia and non-Hodgkin lymphoma and those diagnosed with rob(13;14) of breast cancer., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.)

Genomic analyses of cancer have identified recurrent point mutations in the RNA splicing factor-encoding genes SF3B1, U2AF1, and SRSF2 that confer an alteration of function. Cancer cells bearing these mutations are preferentially dependent on wild-type (WT) spliceosome function, but clinically relevant means to therapeutically target the spliceosome do not currently exist. Here we describe an orally available modulator of the SF3b complex, H3B-8800, which potently and preferentially kills spliceosome-mutant epithelial and hematologic tumor cells. These killing effects of H3B-8800 are due to its direct interaction with the SF3b complex, as evidenced by loss of H3B-8800 activity in drug-resistant cells bearing mutations in genes encoding SF3b components. Although H3B-8800 modulates WT and mutant spliceosome activity, the preferential killing of spliceosome-mutant cells is due to retention of short, GC-rich introns, which are enriched for genes encoding spliceosome components. These data demonstrate the therapeutic potential of splicing modulation in spliceosome-mutant cancers.

In recent years, immune checkpoint inhibitors (ICpI) have provided the ground to bring tumor immunity back to life thanks to their capacity to afford a real clinical benefit in terms of patient's survival. Essential to ICpI success is the presence of tumor-associated neoantigens generated by non-synonymous mutations, since a direct relationship between mutation load of malignant cells and susceptibility to ICpI has been confidently established. However, it has been also suggested that high intratumor heterogeneity (ITH) associated with subclonal neoantigens could not elicit adequate immune responses. Several years ago we discovered that in vivo treatment of leukemic mice with triazene compounds (TZC) produces a marked increase of leukemia cell immunogenicity [a phenomenon termed Drug-Induced Xenogenization (DIX)] through point mutations able to generate strong tumor neoantigens (Drug-Induced Neoantigens, DIN). Immunogenic mutations are produced by TZC-dependent methylation of O6-guanine of DNA, that is suppressed by the DNA repair protein methyl-guaninemethyltransferase (MGMT). This minireview illustrates preclinical investigations conducted in animal models where DIN-positive murine leukemia cells were inoculated intracerebrally into histocompatible mice. The analysis of the literature indicates that the growth of xenogenized malignant cells is controlled by anti-DIN graft responses and by intra-cerebral or intravenous adoptive transfer of anti-DIN cytotoxic T lymphocytes. This survey reminds also that PARP inhibitors increase substantially the antitumor activity of TZC and can be administered with the intent of suppressing more efficiently tumor load and possibly reducing ITH through downsizing the polyclonality of xenogenized tumor cell population. Finally, the present report illustrates a hypothetical clinical protocol that could be considered as an example of future development of DIXbased tumor immuno-chemotherapy in brain malignancies. The protocol involves oral or intravenous administration of TZC along with loco-regional (i.e. intracerebral "wafer") treatment with agents able to increase tumor cell sensitivity to the cytotoxic and xenogenizing effects of TZC (i.e. MGMT and PARP inhibitors) without enhancing the systemic toxicity of these DNA methylating compounds., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Osteopontin (OPN) is a glycoprotein involved in regulation of various influences on tumor progression, such as cellular proliferation, apoptosis, angiogenesis, and metastasis. Vascular endothelial growth factor (VEGF) is a secreted molecule supporting angiogenesis in various cancers through activation of the PI3K/AKT/ERK1/2 pathway. OPN and VEGF have a number of isoforms with various activities. In spite of the well-defined association between OPN and VEGF isoform expression and cure rate for solid tumors, there is a scarcity of information as to any association in leukemia. Based on the critical role of OPN in cell survival, it seems reasonable to hypothesize that OPN and VEGF isoform expression levels may impact on chemoresistance and relapse in leukemia the same as in solid tumors. Hence, the aim of our review was to explain relationships between OPN and VEGF isoforms and angiogenesis and related pathways in chemoresistance of leukemia and solid tumors. Our findings demonstrated that OPNb and OPNc alongside with VEGF isoforms and other gene pathways are involved in angiogenesis and also might promote chemoresistance and even recurrence in leukemia and solid tumors. To sum up, targeting OPN isoforms, particularly b and c, might be a novel therapeutic strategy for the treatment of leukemia as well as solid tumors., (Creative Commons Attribution License)

Analysis of molecular aberrations across multiple cancer types, known as pan-cancer analysis, identifies commonalities and differences in key biological processes that are dysregulated in cancer cells from diverse lineages. Pan-cancer analyses have been performed for adult but not paediatric cancers, which commonly occur in developing mesodermic rather than adult epithelial tissues. Here we present a pan-cancer study of somatic alterations, including single nucleotide variants, small insertions or deletions, structural variations, copy number alterations, gene fusions and internal tandem duplications in 1,699 paediatric leukaemias and solid tumours across six histotypes, with whole-genome, whole-exome and transcriptome sequencing data processed under a uniform analytical framework. We report 142 driver genes in paediatric cancers, of which only 45% match those found in adult pan-cancer studies; copy number alterations and structural variants constituted the majority (62%) of events. Eleven genome-wide mutational signatures were identified, including one attributed to ultraviolet-light exposure in eight aneuploid leukaemias. Transcription of the mutant allele was detectable for 34% of protein-coding mutations, and 20% exhibited allele-specific expression. These data provide a comprehensive genomic architecture for paediatric cancers and emphasize the need for paediatric cancer-specific development of precision therapies.

DNA methyltransferases make use of alternative splicing mechanism to generate various splice variants, but their role(s) in modulating DNA methylation patterns in the cells is unclear. Notably, DNMT3B alone contains nearly 40 different splice variants. In this study, we have identified a novel splice variant of DNMT3B, which lacks exon 7 and 10 from leukemic cell lines which we termed as DNMT3B9. The exon 7 codes for the major part of PWWP domain, and exon 10 inclusion serves as a pluripotent marker. By quantitative RT-PCR using exon-exon junction-specific primers, we showed higher level of DNMT3B9 transcripts in several leukemic cell lines. However, DNMT3B9 expression was less in other tested cancer cell lines indicating that DNMT3B9 might serve as a leukemic-specific biomarker. Surprisingly, endogenous protein for DNMT3B9 was not detected in leukemic cells suggesting the unidentified RNA-related function(s) for DNMT3B9. In addition, we showed that DNMT3B9 protein lacks PWWP domain is less stable compared to other DNMT3B variants which contain PWWP domain through computational predictions and by cycloheximide half-life experiment. Taken together, we demonstrated the existence of novel leukemic-specific splice variant of DNMT3B and provide the evidence for the role of PWWP domain in the stability of DNMT3B. The findings reported here have relevance in epigenetic therapy, which is aimed to target the DNMT3B in cancer cells.

The detection of circulating tumor cells (CTCs) in the blood of cancer patients is a challenging task. CTCs are, especially at the early stages of cancer development, extremely rare cells hidden in a vast background of regular blood cells. We describe a new strategy for the isolation of CTCs from whole blood. The key component is a medical wire coated with a multilayer assembly that allows highly specific capture of EpCAM (epithelial cell adhesion molecule) positive CTCs from blood. The assembly is generated in a layer-by-layer fashion through photochemically induced C,H insertion reactions and consists of a protective layer, which shields the contacting solution from the metal, a protein resistant layer, which prevents nonspecific interactions with proteins and a layer containing the EpCAM antibodies. In vitro experiments show that these surfaces can capture tumor cells from whole blood with enrichment factors (specifically vs nonspecifically bound cells) of up to about 3000 compared to the number of leucocytes in the blood. The purity of the isolated cells is greater than 90%. After "fishing" them from the blood, the cells, still bound to the wire, can be genetically analyzed. This demonstrates that this strategy might prove useful for next generation sequencing.