KMT2A

Gene Summary

Gene:KMT2A; lysine methyltransferase 2A
Aliases: HRX, MLL, MLL1, TRX1, ALL-1, CXXC7, HTRX1, MLL1A, WDSTS
Location:11q23.3
Summary:This gene encodes a transcriptional coactivator that plays an essential role in regulating gene expression during early development and hematopoiesis. The encoded protein contains multiple conserved functional domains. One of these domains, the SET domain, is responsible for its histone H3 lysine 4 (H3K4) methyltransferase activity which mediates chromatin modifications associated with epigenetic transcriptional activation. This protein is processed by the enzyme Taspase 1 into two fragments, MLL-C and MLL-N. These fragments reassociate and further assemble into different multiprotein complexes that regulate the transcription of specific target genes, including many of the HOX genes. Multiple chromosomal translocations involving this gene are the cause of certain acute lymphoid leukemias and acute myeloid leukemias. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Oct 2010]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:histone-lysine N-methyltransferase 2A
Source:NCBIAccessed: 31 August, 2019

Ontology:

What does this gene/protein do?
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Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 31 August 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (18)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Entity Topic PubMed Papers
Acute Lymphocytic Leukaemia (ALL)t(10;11)(p12;q23) AF10-MLL translocation in Acute Leukaemia View Publications140
Acute Lymphocytic Leukaemia (ALL)t(11;19)(q23;p13.1) MLL-ELL translocation in acute leukaemia View Publications22
Acute Lymphocytic Leukemia (ALL), childins(5;11)(q31;q31q23) MLL-AFF4 in Infant Acute lymphoblastic Leukemia View Publications13
Acute Myeloid Leukaemia (AML)t(1;11)(p32;q23) MLL-EPS15 fusion in Acute Myelogeneous Leukemia View Publications12
Acute Lymphocytic Leukaemia (ALL)t(10;11) MLL-TET1 rearrangement in acute leukemias View Publications5
Haematological MalignanciesKMT2A and Haematological Malignancies View Publications13
Leukaemiat(10;11)(p11.2;q23) ABI1-MLL translocation in Leukemia View Publications2
-KMT2A and Residual Disease View Publications23
Lung CancerKMT2A and Lung Cancer View Publications5
Prostate CancerKMT2A and Prostate Cancer View Publications8
Acute Myeloid Leukaemia (AML)t(1;11) (q21;q23) in Leukemia
The MLL gene on chromosome 11 is frequently involved in translocations with a range of other genes. Tse et al, 1995 identified the AF1q (MLLT11) gene and t(1;11)(q21;q23) translocation of AF1q/MLL. In a series of 45 leukemia patients with MLL rearagements Cerveira et al, 2012 found 2 (4%) had the AF1q/MLL translocation.
Cervical CancerKMT2A and Cervical Cancer View Publications2
Acute Lymphocytic Leukemia (ALL), childt(4;11)(q21;q23) in Infant Leukaemia
Acute Myeloid Leukaemia (AML)t(6;11)(q27;q23) in Acute Myeloid Leukemia
Acute Lymphocytic Leukaemia (ALL)t(4;11)(q21;q23) MLL-AFF1 in adult acute lymphoblastic leukemia
Acute Myeloid Leukaemia (AML)t(9;11) in Acute Myeloid Leukaemia
-t(11;17) ALL1-MLLT6 in Acute Leukaemias
Leukaemiat(11;19)(q23;p13) in Leukaemia

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: KMT2A (cancer-related)

Chu Y, Chen Y, Li M, et al.
Six1 regulates leukemia stem cell maintenance in acute myeloid leukemia.
Cancer Sci. 2019; 110(7):2200-2210 [PubMed] Free Access to Full Article Related Publications
Molecular genetic changes in acute myeloid leukemia (AML) play crucial roles in leukemogenesis, including recurrent chromosome translocations, epigenetic/spliceosome mutations and transcription factor aberrations. Six1, a transcription factor of the Sine oculis homeobox (Six) family, has been shown to transform normal hematopoietic progenitors into leukemia in cooperation with Eya. However, the specific role and the underlying mechanism of Six1 in leukemia maintenance remain unexplored. Here, we showed increased expression of SIX1 in AML patients and murine leukemia stem cells (c-Kit

Sengupta D, Deb M, Kar S, et al.
miR-193a targets MLL1 mRNA and drastically decreases MLL1 protein production: Ectopic expression of the miRNA aberrantly lowers H3K4me3 content of the chromatin and hampers cell proliferation and viability.
Gene. 2019; 705:22-35 [PubMed] Related Publications
Mixed-lineage leukaemia 1 (MLL1) enzyme plays major role in regulating genes associated with vertebrate development. Cell physiology and homeostasis is regulated by microRNAs in diverse microenvironment. In this investigation we have identified conserved miR-193a target sites within the 3'-UTR of MLL1 gene transcript. Utilizing wild type and mutated 3'-UTR constructs and luciferase reporter assays we have clearly demonstrated that miR-193a directly targets the 3'-UTR region of the MLL1 mRNA. Ectopic expression of miR-193a modulated global H3K4 mono-, di- and tri-methylation levels and affects the expression of CAV1, a gene which is specifically modulated by H3K4me3. To determine the implications of this in vitro finding in aberrant physiological conditions we analyzed prostate cancer tissue samples. In this context miR-193a RNA was undetectable and MLL1 was highly expressed with concomitantly high levels of H3K4me, H3K4me2, and H3K4me3 enrichment in the promoters of MLL1 responsive genes. Finally, we showed that prolonged ectopic expression of miR-193a inhibits growth and cell migration, and induces apoptosis. Thus, while our study unveils amplitude of the epigenome, including miRnome it establishes that; (i) miR-193a directly target MLL1 mRNA, (ii) miR-193a impair MLL1 protein production, (iii) miR-193a reduces the overall methylation marks of the genome.

Capela de Matos RR, Ney Garcia DR, Othman MAK, et al.
A New Complex Karyotype Involving a KMT2A-r Variant Three-Way Translocation in a Rare Clinical Presentation of a Pediatric Patient with Acute Myeloid Leukemia.
Cytogenet Genome Res. 2019; 157(4):213-219 [PubMed] Related Publications
Patients with childhood acute myeloid leukemia (AML) with complex karyotypes (CKs) have a dismal outcome. However, for patients with a KMT2A rearrangement (KMT2A-r), the prognosis appears to depend on the fusion partner gene rather than the karyotype structure. Thus, a precise characterization of KMT2A-r and the fusion partner genes, especially in CKs, is of interest for managing AML. We describe the clinical and molecular features of a child who presented with a large abdominal mass, AML, and a new CK, involving chromosomes 11, 16, and 19 leading to a KMT2A-MLLT1 fusion and 2 extra copies of the ELL gene, thus resulting in the concurrent overexpression of MLLT1 and ELL. Molecular cytogenetic studies defined the karyotype as 47,XY,der(11)t(11;16)(q23.3;p11.2),der(16)t(16;19)(p11.2;p13.3),der(19)t(11;19)(q23.3;p13.3),+der(19)t(16;19)(16pter→p11.2::19p13.3→19q11::19p11→19p13.3::16p11.2→16pter). Array CGH revealed a gain of 30.5 Mb in the 16p13.3p11.2 region and a gain of 18.1 Mb in the 19p13.3p12 region. LDI-PCR demonstrated the KMT2A-MLLT1 fusion. Reverse sequence analysis showed that the MLLT1 gene was fused to the 16p11.2 region. RT-qPCR quantification revealed that ELL and MLLT1 were overexpressed (4- and 10-fold, respectively). In summary, this is a pediatric case of AML presenting a novel complex t(11;16;19) variant with overexpression of ELL and MLLT1.

Sharma ND, Nickl CK, Kang H, et al.
Epigenetic silencing of SOCS5 potentiates JAK-STAT signaling and progression of T-cell acute lymphoblastic leukemia.
Cancer Sci. 2019; 110(6):1931-1946 [PubMed] Free Access to Full Article Related Publications
Activating mutations in cytokine receptors and transcriptional regulators govern aberrant signal transduction in T-cell lineage acute lymphoblastic leukemia (T-ALL). However, the roles played by suppressors of cytokine signaling remain incompletely understood. We examined the regulatory roles of suppressor of cytokine signaling 5 (SOCS5) in T-ALL cellular signaling networks and leukemia progression. We found that SOCS5 was differentially expressed in primary T-ALL and its expression levels were lowered in HOXA-deregulated leukemia harboring KMT2A gene rearrangements. Here, we report that SOCS5 expression is epigenetically regulated by DNA methyltransferase-3A-mediated DNA methylation and methyl CpG binding protein-2-mediated histone deacetylation. We show that SOCS5 negatively regulates T-ALL cell growth and cell cycle progression but has no effect on apoptotic cell death. Mechanistically, SOCS5 silencing induces activation of JAK-STAT signaling, and negatively regulates interleukin-7 and interleukin-4 receptors. Using a human T-ALL murine xenograft model, we show that genetic inactivation of SOCS5 accelerates leukemia engraftment and progression, and leukemia burden. We postulate that SOCS5 is epigenetically deregulated in T-ALL and serves as an important regulator of T-ALL cell proliferation and leukemic progression. Our results link aberrant downregulation of SOCS5 expression to the enhanced activation of the JAK-STAT and cytokine receptor-signaling cascade in T-ALL.

Bao H, Gao J, Chen YH, et al.
Rare myeloid sarcoma with KMT2A (MLL)-ELL fusion presenting as a vaginal wall mass.
Diagn Pathol. 2019; 14(1):26 [PubMed] Free Access to Full Article Related Publications
BACKGROUD: Myeloid sarcoma (MS) is a rare neoplasm of immature myeloid precursors that form tumor mass outside the bone marrow. The diagnosis of de novo MS can be challenging, particularly in patients with no prior history of hematologic malignancies or when MS involves unusual anatomic sites.
CASE PRESENTATION: The patient was a 53-year-old woman with a history of uterine fibroids and vaginal bleeding for many years who presented with a vaginal wall mass. The tumor had histologic and phenotypic features of histiocytic sarcoma, however, overlapping with a possible extramedullary MS. Using a comprehensive genomic profiling, we were able to identify recurrent chromosomal aberrations associated with MS including a rare KMT2A-ELL fusion, losses of chromosomes 1p, 9, 10, 15, 18, and gain of chromosome 1q and mutations in FLT3 and PTPN11, and achived the final diagnosis of a de novo MS. The patient received standard treatment for acute myeloid leukemia regimen with stem cell transplantation and achieved complete remission.
CONCLUSION: Our case illustrates the clinical utility of comprehensive genomic profiling in assisting the diagnosis or differential diagnosis of challenging MS or histiocytic sarcoma cases, and in providing important information in tumor biology for appropriate clinical management.

Wang YM, Mo JQ, Kuo DJ, Wong V
BMJ Case Rep. 2019; 12(2) [PubMed] Related Publications
We describe an unusual case of pre-B lymphoblastic leukaemia presenting with a unilateral maxillary sinus mass in which biopsies of the primary mass and the bone marrow demonstrated conflicting immunophenotyping results. The extramedullary mass was consistent with a precursor B-cell malignancy, while the bone marrow was initially reported as a possible mature B-cell malignancy. The treatments for the two are fundamentally different, which necessitated a delay in the initiation of his chemotherapy until a clear diagnosis was made. Mixed lineage leukaemia gene rearrangement was confirmed by fluorescence in situ hybridisation in both the primary mass and bone marrow, which unified the diagnosis as pre-B acute lymphoblastic leukaemia given the common cytogenetic feature.

Valent P, Kern W, Hoermann G, et al.
Clonal Hematopoiesis with Oncogenic Potential (CHOP): Separation from CHIP and Roads to AML.
Int J Mol Sci. 2019; 20(3) [PubMed] Free Access to Full Article Related Publications
The development of leukemia is a step-wise process that is associated with molecular diversification and clonal selection of neoplastic stem cells. Depending on the number and combinations of lesions, one or more sub-clones expand/s after a variable latency period. Initial stages may develop early in life or later in adulthood and include premalignant (indolent) stages and the malignant phase, defined by an acute leukemia. We recently proposed a cancer model in which the earliest somatic lesions are often age-related early mutations detectable in apparently healthy individuals and where additional oncogenic mutations will lead to the development of an overt neoplasm that is usually a preleukemic condition such as a myelodysplastic syndrome. These neoplasms may or may not transform to overt acute leukemia over time. Thus, depending on the type and number of somatic mutations, clonal hematopoiesis (CH) can be divided into CH with indeterminate potential (CHIP) and CH with oncogenic potential (CHOP). Whereas CHIP mutations

Piskunova IS, Obukhova TN, Parovichnikova EN, et al.
Structure and significance of cytogenetic abnormalities in adult patients with Ph-negative acute lymphoblastic leukemia.
Ter Arkh. 2018; 90(7):30-37 [PubMed] Related Publications
AIM: To evaluate occurrence, variety, structural peculiarities and prognostic meaning of cytogenetic abnormalities in adult patients with Ph-negative acute lymphoblastic leukemia (ALL) receiving therapy according to ALL-2009 protocol.
MATERIALS AND METHODS: The study included 115 adult patients with firstly diagnosed Ph-negative ALL: 58 male and 57 female aged from 15 to 61 years (mean age 26.5 years), who underwent treatment from September 2009 to September 2015 in National Medical Research Center for Hematology MH RF (n=101) and in hematology departments of regional hospitals (n=14). All patients received therapy of ALL-2009 protocol (ClinicalTrials.gov, NCT01193933). The median follow-up was 24.5 months (0.2-94.4 months). As a part of the study results of a standard cytogenetic assay (SCA) were analyzed and fluorescence hybridization in situ (FISH) with the use of DNA-probes was performed on archived biological material for structural changes in gene locuses MLL/t(11q23), с-MYC/t(8q24), TP53/ deletion 17p13, CDKN2A/ deletion 9p21, translocation t(1;19)/E2A-PBX1 и t(12;21)/ETV6-RUNX1; iAMP21 identification.
RESULTS: Karyotype was defined using SCA in 86% of patients. Normal karyotype was found in 48.5% of them, chromosome aberrations in 51.5% (structural changes were found in 19.2%, hyperploidy in 27.2%, and hypoploidy in 5.1%). In 17.2% of patients complex karyotype abnormalities were found. With the use of FISH technique aberrations were found in 67% of patients: 9p21/CDKN2A deletion in 24.3%, MLL/t(11q23) gene abnormalities in 7.8%, 17p13/TP53 deletion in 5.2%, abnormalities of c-MYC/t(8q24) in 1.7%, t(1;19)/E2A-PBX1 in 0.8%, and iAMP21 in 0.8%, other abnormalities (additional signals/absence of signals from gene locuses) in 26.4%, t(12;21)/ETV6-RUNX1 was not found. FISH technique use in addition to SCA allows to increase aberrant karyotype location from 51.5 to 67%. A statistically significant correlation of 9p21/CDKN2A deletion with high serum lactate dehydrogenase activity (p=0.02); MLL/t(11q23) gene abnormalities - with leucocytosis and high blast cells level in blood (p=0.0016), hyperploidy - with normal leukocyte count (p=0.02) was shown. In groups with different cytogenetic abnormalities no statistically significant differences of treatment with ALL-2009 protocol were found (in terms of complete remission, early mortality and treatment resistance). When connection of cytogenetic abnormalities and their combinations with long-term results were analyzed according to ALL-2009 protocol, only two characteristics - MLL/t(11q23) and c MYC/t(8q24) gene abnormalities had a statistically significant influence on disease-free survival (HR - 176.9; p<0.0001) and chance of recurrence (HR - 6.4; p=0.02).
CONCLUSION: Adverse prognostic factors in terms of therapeutic management provided in ALL-2009 protocol were MLL/t(11q23) and с-MYC/t(8q24) genes abnormalities. CDKN2A/9p21 and TP53/17p13 genes deletions, quantative and complex karyotype abnormalities were not prognostic factors in adult patients with Ph-negative ALL in ALL-2009 protocol use.

Zerkalenkova E, Lebedeva S, Kazakova A, et al.
Acute myeloid leukemia with t(10;11)(p11-12;q23.3): Results of Russian Pediatric AML registration study.
Int J Lab Hematol. 2019; 41(2):287-292 [PubMed] Related Publications
INTRODUCTION: Translocations involving the KMT2A gene (also known as MLL) are frequently diagnosed in pediatric acute leukemia cases with either lymphoblastic or myeloid origin. KMT2A is translocated to multiple partner genes, including MLLT10/AF10 localizing at chromosomal band 10p12. KMT2A-MLLT10 is one of the common chimeric genes diagnosed in acute leukemia with KMT2A rearrangement (8%), especially in acute myeloid leukemia (AML; 18%). MLLT10 is localized in very close proximity to two other KMT2A partner genes at 10p11-12-NEBL and ABI1, so they could not be distinguished by conventional cytogenetics.
METHODS: In this work, we present a cohort of 28 patients enrolled into Russian Pediatric AML registration study carrying rearrangements between chromosomal regions 11q23.3 and 10p11-12. G-banding, FISH, reverse transcription PCR, and long-distance inverse PCR were used to characterize the KMT2A gene rearrangements in these patients.
RESULTS: We demonstrate that 25 patients harbor the KMT2A-MLLT10 rearrangement, while three patients show the rare KMT2A rearrangements (2× KMT2A-NEBL; 1× KMT2A-ABI1).
CONCLUSIONS: Therefore, the combination of cytogenetic and molecular genetic methods is of high importance in diagnosing cases with t(10;11)(p11-12;q23.3).

Zhang Y, Yan L, Yao W, et al.
Integrated Analysis of Genetic Abnormalities of the Histone Lysine Methyltransferases in Prostate Cancer.
Med Sci Monit. 2019; 25:193-239 [PubMed] Free Access to Full Article Related Publications
BACKGROUND The histone methyltransferase (HMT) family includes histone lysine methyltransferases (HKMTs) and histone/protein arginine methyltransferases (PRMTs). The role of HMT gene variants in prostate cancer remains unknown. Therefore, this study aimed to evaluate HMT gene variants in the pathogenesis and prognosis of human prostate cancer, using in vitro cell studies and bioinformatics analysis. MATERIAL AND METHODS Integrative bioinformatics analysis of the expression of 51 HMT genes in human prostate cancer was based on datasets from the Cancer Genome Atlas (TCGA). Correlation and regression analysis were used to identify critical HMTs in prostate cancer. Kaplan-Meier and the area under the receiver operating characteristics curve (AUROC) were performed to evaluate the function of the HMTs on prognosis. Gene expression and function of 22Rv1 human prostate carcinoma cells were studied. RESULTS The HMT genes identified to have a role in the pathogenesis of prostate cancer included the EZH2, SETD5, PRDM12, NSD1, SETD6, SMYD1, and the WHSC1L1 gene. The EZH2, SETD5, and SMYD1 genes were selected as a prognostic panel, with the SUV420H2 HMT gene. SETD2, NSD1, and ASH1L were identified as critical genes in the development of castration-resistant prostate cancer (CRPC), similar to mixed-lineage leukemia (MLL) complex family members. Knockdown of the SETD5 gene in 22Rv1 prostate carcinoma cells in vitro inhibited cancer cell growth and migration. CONCLUSIONS HMT gene variants may have a role in the pathogenesis of prostate cancer. Future studies may determine the role of HMT genes as prognostic biomarkers in patients with prostate cancer.

Stratmann JA, von Rose AB, Koschade S, et al.
Clinical and genetic characterization of de novo double-hit B cell precursor leukemia/lymphoma.
Ann Hematol. 2019; 98(3):647-656 [PubMed] Related Publications
The 2016 revised World Health Organization (WHO) classification of lymphoid neoplasms included the category of high-grade B cell lymphomas (HGBLs) with combined MYC and BCL2 and/or BCL6 rearrangements (double-hit, DH). However, the clinical features of B cell precursor leukemia (BCP-ALL) that harbor DH genetics remain widely unknown. We performed a retrospective analysis of the German Multicenter Study Group for Adult ALL registry and a literature search for de novo DH-BCP-ALLs. We identified 6 patients in the GMALL registry and 11 patients published in the literature between 1983 and June 2018. Patients of all ages (range, 15-86 years) are affected. There is a high incidence of meningeal disease and other extramedullary disease manifestations. Current treatment approaches are mainly ALL-based and are sufficient to induce first complete remissions, but progression-free survival is only 4.0 months (95% CI, 1.5-6.5 months) and all patients succumb to their disease, once relapsed, with a median survival of 5.0 months (95% CI, 3.1-6.9 months), despite intensive salvage and targeted therapy approaches. Of all patients, only two that attained an initial complete remission were alive at data cutoff. In all cases, the BCL2 gene was rearranged to be in proximity to the IGH locus, whereas MYC had various translocation partners juxtaposed. There was no significant survival difference between IG and non-IG translocation partners (HR, 1.03; 95% CI, 0.33-3.2; p = 0.89). In conclusion, de novo DH-BCP-ALL is an aggressive B cell malignancy with deleterious outcome. Physicians have to be aware of this rare disease subset due to the atypical clinical behavior and especially because latest classification systems do not cover this sub-entity.

Martin-Guerrero I, Salaverria I, Burkhardt B, et al.
Non-leukemic pediatric mixed phenotype acute leukemia/lymphoma: Genomic characterization and clinical outcome in a prospective trial for pediatric lymphoblastic lymphoma.
Genes Chromosomes Cancer. 2019; 58(6):365-372 [PubMed] Related Publications
Rare cases of hematological precursor neoplasms fulfill the diagnostic criteria of mixed phenotype acute leukemia (MPAL), characterized by expression patterns of at least two hematopoietic lineages, for which a highly aggressive behavior was reported. We present a series of 11 pediatric non-leukemic MPAL identified among 146 precursor lymphoblastic lymphomas included in the prospective trial Euro-LBL 02. Paraffin-embedded biopsies of 10 cases were suitable for molecular analyses using OncoScan assay (n = 7), fluorescence in situ hybridization (FISH; n = 7) or both (n = 5). Except for one case with biallelic KMT2A (MLL) breaks, all cases analyzed by FISH lacked the most common translocations defining molecular subsets of lymphoblastic leukemia/lymphomas. Two non-leukemic B-myeloid MPALs showed the typical genomic profile of hyperdiploid precursor B-cell lymphoblastic leukemia with gains of chromosomes 4, 6, 10, 14, 18, and 21. One B-T MPAL showed typical aberrations of T-cell lymphoblastic lymphoma, such as copy number neutral loss of heterozygosity (CNN-LOH) at 9p targeting a 9p21.3 deletion of CDKN2A and 11q12.2-qter affecting the ATM gene. ATM was also mutated in a T-myeloid MPAL case with additional loss at 7q21.2-q36.3 and mutation of NRAS, two alterations common in myeloid disorders. No recurrent regions of CNN-LOH were observed. The outcome under treatment was good with all patients being alive in first complete remission after treatment according to a protocol for precursor lymphoblastic lymphoma (follow-up 3-10 years, median: 4.9 years). In summary, the present series of non-leukemic MPALs widely lacked recurrently reported translocations in lymphoid/myeloid neoplasias and showed heterogeneous spectrum of chromosomal imbalances.

Zhao Z, Wang L, Volk AG, et al.
Regulation of MLL/COMPASS stability through its proteolytic cleavage by taspase1 as a possible approach for clinical therapy of leukemia.
Genes Dev. 2019; 33(1-2):61-74 [PubMed] Free Access to Full Article Related Publications
Chromosomal translocations of the Mixed-lineage leukemia 1 (

Tzelepis K, De Braekeleer E, Aspris D, et al.
SRPK1 maintains acute myeloid leukemia through effects on isoform usage of epigenetic regulators including BRD4.
Nat Commun. 2018; 9(1):5378 [PubMed] Free Access to Full Article Related Publications
We recently identified the splicing kinase gene SRPK1 as a genetic vulnerability of acute myeloid leukemia (AML). Here, we show that genetic or pharmacological inhibition of SRPK1 leads to cell cycle arrest, leukemic cell differentiation and prolonged survival of mice transplanted with MLL-rearranged AML. RNA-seq analysis demonstrates that SRPK1 inhibition leads to altered isoform levels of many genes including several with established roles in leukemogenesis such as MYB, BRD4 and MED24. We focus on BRD4 as its main isoforms have distinct molecular properties and find that SRPK1 inhibition produces a significant switch from the short to the long isoform at the mRNA and protein levels. This was associated with BRD4 eviction from genomic loci involved in leukemogenesis including BCL2 and MYC. We go on to show that this switch mediates at least part of the anti-leukemic effects of SRPK1 inhibition. Our findings reveal that SRPK1 represents a plausible new therapeutic target against AML.

Brassesco MS, Valera ET, Meyer C, et al.
A new complex rearrangement in infant ALL: t(X;11;17)(p11.2;q23;q12).
Cancer Genet. 2018; 228-229:110-114 [PubMed] Related Publications
We present a case of an infant who developed pro-B acute lymphoblastic leukemia with a rare and complex MLL-translocation. Cytogenetic analysis of bone marrow cells at diagnosis showed a 46,XY,t(X;11)(p11.2;q23)[13]/46,XY[7] karyotype. Fluorescence in situ hybridization analysis using a break apart specific probes showed a split in the MLL gene. Long distance inverse-PCR and next generation sequencing analysis depicted a complex rearrangement t(X;11;17)(p11.2;q23;q12) involving MLL, MLLT6 and the genomic region Xp11.23, 41 bases upstream of the WDR45 gene. WDR45 encodes a beta-propeller protein essential for autophagocytosis. MLL rearrangements with involvement of Xp have not been previously described.

Zhang LS, Kang X, Lu J, et al.
Installation of a cancer promoting WNT/SIX1 signaling axis by the oncofusion protein MLL-AF9.
EBioMedicine. 2019; 39:145-158 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Chromosomal translocation-induced expression of the chromatin modifying oncofusion protein MLL-AF9 promotes acute myelocytic leukemia (AML). Whereas WNT/β-catenin signaling has previously been shown to support MLL-AF9-driven leukemogenesis, the mechanism underlying this relationship remains unclear.
METHODS: We used two novel small molecules targeting WNT signaling as well as a genetically modified mouse model that allow targeted deletion of the WNT protein chaperone Wntless (WLS) to evaluate the role of WNT signaling in AML progression. ATAC-seq and transcriptome profiling were deployed to understand the cellular consequences of disrupting a WNT signaling in leukemic initiating cells (LICs).
FINDINGS: We identified Six1 to be a WNT-controlled target gene in MLL-AF9-transformed leukemic initiating cells (LICs). MLL-AF9 alters the accessibility of Six1 DNA to the transcriptional effector TCF7L2, a transducer of WNT/β-catenin gene expression changes. Disruption of WNT/SIX1 signaling using inhibitors of the Wnt signaling delays the development of AML.
INTERPRETATION: By rendering TCF/LEF-binding elements controlling Six1 accessible to TCF7L2, MLL-AF9 promotes WNT/β-catenin-dependent growth of LICs. Small molecules disrupting WNT/β-catenin signaling block Six1 expression thereby disrupting leukemia driven by MLL fusion proteins.

Lu B, Klingbeil O, Tarumoto Y, et al.
A Transcription Factor Addiction in Leukemia Imposed by the MLL Promoter Sequence.
Cancer Cell. 2018; 34(6):970-981.e8 [PubMed] Free Access to Full Article Related Publications
The Mixed Lineage Leukemia gene (MLL) is altered in leukemia by chromosomal translocations to produce oncoproteins composed of the MLL N-terminus fused to the C-terminus of a partner protein. Here, we used domain-focused CRISPR screening to identify ZFP64 as an essential transcription factor in MLL-rearranged leukemia. We show that the critical function of ZFP64 in leukemia is to maintain MLL expression via binding to the MLL promoter, which is the most enriched location of ZFP64 occupancy in the human genome. The specificity of ZFP64 for MLL is accounted for by an exceptional density of ZFP64 motifs embedded within the MLL promoter. These findings demonstrate how a sequence anomaly of an oncogene promoter can impose a transcriptional addiction in cancer.

Li JF, Dai YT, Lilljebjörn H, et al.
Transcriptional landscape of B cell precursor acute lymphoblastic leukemia based on an international study of 1,223 cases.
Proc Natl Acad Sci U S A. 2018; 115(50):E11711-E11720 [PubMed] Free Access to Full Article Related Publications
Most B cell precursor acute lymphoblastic leukemia (BCP ALL) can be classified into known major genetic subtypes, while a substantial proportion of BCP ALL remains poorly characterized in relation to its underlying genomic abnormalities. We therefore initiated a large-scale international study to reanalyze and delineate the transcriptome landscape of 1,223 BCP ALL cases using RNA sequencing. Fourteen BCP ALL gene expression subgroups (G1 to G14) were identified. Apart from extending eight previously described subgroups (G1 to G8 associated with

Singh M, Bhatia P, Shandilya JK, et al.
Low Expression of Leucocyte Associated Immunoglobulin Like Receptor-1 (LAIR-1/CD305) in a Cohort of Pediatric Acute Lymphoblastic Leukemia Cases
Asian Pac J Cancer Prev. 2018; 19(11):3131-3135 [PubMed] Free Access to Full Article Related Publications
Background: Immunophenotypic markers can play significant role in prognostic assessment for different cancers and leukocyte-associated Ig-like receptor (LAIR-1) is a recently identified inhibitory immuno-receptor. Methods: We measured LAIR-1 expression in paediatric ALL patients (n-42) and appropriate controls by flow cytometry. Median fluorescence intensities (MFIs) were calculated and correlated with demographic and clinical variables and early treatment outcome parameters. Results: The ALL cohort had an age range of 1 - 11 y and a M:F ratio of 2.5:1. 64% had WBC counts <50 x 109/L and 15 (36%) >50 x 109/L, 52% being standard risk and 48% high risk. There were 6 cases of T-ALL and 36 of B-ALL. AML1-TEL, E2A-PBX, BCR-ABL and MLL-AF4 transcripts were noted in 3, 6, 2 and 1 patient, respectively. Day 8 ABC was <1,000 in 31 and >1,000 in 8 cases, while 30 had low and 7 high MRD (both >0.01) at day 35 of treatment. The median MFI for LAIR-1 expression in control cases was 8.2 (range 7.76-11.69) and in ALL cases 4.02 (range 0.56 to 11.87), with 74% (n-31) of ALL cases showing reduced LAIR-1 expression. However, no significant correlations were found between standard ALL risk factors and LAIR-1 expression. Out of 42 patients, 4 died during induction treatment and one exited therapy, 60% (n-3/5) of these featuring low expression of LAIR-1. Also ALL patients with low LAIR-1 expression had t (12;21), t (1;19) and t (4;11) translocations in 2, 4 and 1 samples, respectively, but none had t (9;22). Of those with high LAIR-1 expression, 2 had t (9;22) (MFIs-14.43 and 11.87). Conclusions: This pilot study of LAIR-1expression in ALL suggests low expression of the inhibitory molecule in leukemic cells. However, the findings need to be confirmed with larger cohort, along with studies focusing on pathophysiological roles in leukemic clone survival and escape from the immune system.

Urtishak KA, Wang LS, Culjkovic-Kraljacic B, et al.
Targeting EIF4E signaling with ribavirin in infant acute lymphoblastic leukemia.
Oncogene. 2019; 38(13):2241-2262 [PubMed] Free Access to Full Article Related Publications
The poor outcomes in infant acute lymphoblastic leukemia (ALL) necessitate new treatments. Here we discover that EIF4E protein is elevated in most cases of infant ALL and test EIF4E targeting by the repurposed antiviral agent ribavirin, which has anticancer properties through EIF4E inhibition, as a potential treatment. We find that ribavirin treatment of actively dividing infant ALL cells on bone marrow stromal cells (BMSCs) at clinically achievable concentrations causes robust proliferation inhibition in proportion with EIF4E expression. Further, we find that ribavirin treatment of KMT2A-rearranged (KMT2A-R) infant ALL cells and the KMT2A-AFF1 cell line RS4:11 inhibits EIF4E, leading to decreases in oncogenic EIF4E-regulated cell growth and survival proteins. In ribavirin-sensitive KMT2A-R infant ALL cells and RS4:11 cells, EIF4E-regulated proteins with reduced levels of expression following ribavirin treatment include MYC, MCL1, NBN, BCL2 and BIRC5. Ribavirin-treated RS4:11 cells exhibit impaired EIF4E-dependent nuclear to cytoplasmic export and/or translation of the corresponding mRNAs, as well as reduced phosphorylation of the p-AKT1, p-EIF4EBP1, p-RPS6 and p-EIF4E signaling proteins. This leads to an S-phase cell cycle arrest in RS4:11 cells corresponding to the decreased proliferation. Ribavirin causes nuclear EIF4E to re-localize to the cytoplasm in KMT2A-AFF1 infant ALL and RS4:11 cells, providing further evidence for EIF4E inhibition. Ribavirin slows increases in peripheral blasts in KMT2A-R infant ALL xenograft-bearing mice. Ribavirin cooperates with chemotherapy, particularly L-asparaginase, in reducing live KMT2A-AFF1 infant ALL cells in BMSC co-cultures. This work establishes that EIF4E is broadly elevated across infant ALL and that clinically relevant ribavirin exposures have preclinical activity and effectively inhibit EIF4E in KMT2A-R cases, suggesting promise in EIF4E targeting using ribavirin as a means of treatment.

Brown P, Pieters R, Biondi A
How I treat infant leukemia.
Blood. 2019; 133(3):205-214 [PubMed] Related Publications
Leukemia in infants is rare but generates tremendous interest due to its aggressive clinical presentation in a uniquely vulnerable host, its poor response to current therapies, and its fascinating biology. Increasingly, these biological insights are pointing the way toward novel therapeutic approaches. Using representative clinical case presentations, we review the key clinical, pathologic, and epidemiologic features of infant leukemia, including the high frequency of

Ando N, Furuichi Y, Kasai S, et al.
Chemosensitivity is differentially regulated by the SDF-1/CXCR4 and SDF-1/CXCR7 axes in acute lymphoblastic leukemia with MLL gene rearrangements.
Leuk Res. 2018; 75:36-44 [PubMed] Related Publications
Although recent advances in chemotherapy have markedly improved outcome of acute lymphoblastic leukemia (ALL), infantile ALL with MLL gene rearrangements (MLL+ALL) is refractory to chemotherapy. We have shown that specific cytokines FLT3 ligand and TGFβ1 both of which are produced from bone marrow stromal cells synergistically induced MLL+ALL cells into chemo-resistant quiescence, and that treatment of MLL+ALL cells with inhibitors against FLT3 and/or TGFβ1 receptor partially but significantly converts them toward chemo-sensitive. In the present study, we showed that MLL+ALL cells expressed CXCR4 and CXCR7, both receptors for the same chemokine stromal cell derived factor-1 (SDF-1), but their biological events were differentially regulated by the SDF-1/CXCR4 and SDF-1/CXCR7 axes and particularly exerted an opposite effect for determining chemo-sensitivity of MLL+ALL cells; enhancement via the SDF-1/CXCR4 axis vs. suppression via the SDF-1/CXCR7 axis. Because cytosine-arabinoside-induced apoptosis of MLL+ALL cells was inhibited by pretreatment with the CXCR4 inhibitor but rather accelerated by pretreatment with the CXCR7 inhibitor, an application of the CXCR7 inhibitor may become a good treatment option in future for MLL+ALL patients. MLL+ALL has a unique gene profile distinguishable from other types of ALL and AML, and should be investigated separately in responses to biological active agents including chemokine inhibitors.

Liu B
DPY30 functions in glucose homeostasis via integrating activated histone epigenetic modifications.
Biochem Biophys Res Commun. 2018; 507(1-4):286-290 [PubMed] Related Publications
Glucose homeostasis is a key event during many physiological and pathological processes. Histone modifications have emerged as vital factors influencing this process. DPY30, a core subunit of SET1/MLL family histone H3K4 methyltransferase complexes, has been reported to be amplified in cancers. However, the role of DPY30 in glucose homeostasis remains unclear. Here we reported that DPY30 regulated H3K4me3 recruitment to control the expression of Hif1α and its targeted glycolytic genes. Specifically, DPY30 promoted H3K9Ac recruitment via inhibiting SIRT6 occupancy on these gene promoters. Finally, we observed significant upregulation of DPY30 mRNA expression in hepatocellular carcinoma samples from datasets. Taken together, our results reveal a critical role of DPY30 in glucose homeostasis and might offer new therapeutic and diagnostic opportunities for cancers.

Xu X, Schneider B
Therapeutic targeting potential of chromatin-associated proteins in MLL-rearranged acute leukemia.
Cell Oncol (Dordr). 2019; 42(2):117-130 [PubMed] Related Publications
BACKGROUND: Acute leukemias (AL) with a Mixed Lineage Leukemia (MLL) gene rearrangement (MLLr) represent a group of leukemic entities conferring intermediate to adverse prognoses. Multiple chromatin-associated proteins have been shown to play essential roles during the genesis of MLLr AL. Some chromatin-associated proteins function as negative regulators of MLLr AL whereas others are required for leukemic initiation or maintenance - the latter group constituting potential therapeutic targets. Most of the identified proteins have been functionally analyzed using experimental models with human/murine normal cells transformed by MLL-AF9 or other MLL fusion products, which may recapitulate most but not all aspects of human AML, such as immune system interactions - features of which the importance is rapidly emerging.
CONCLUSIONS: Here, we review chromatin-associated proteins fundamental to MLLr AL development, highlighting those with targeting potential by small molecule inhibitors. In particular, we focus on synthetic targeting of multiple chromatin-associated proteins, a strategy that shows superior therapeutic efficacy and offers hope for overcoming drug resistance.

He Z, Wang B, Chen L, et al.
MLL-PTD in a 13-year-old patient with blast phase myeloproliferative neoplasm: A case report.
Medicine (Baltimore). 2018; 97(46):e13220 [PubMed] Free Access to Full Article Related Publications
RATIONALE: The risk of leukemic transformation in myeloproliferative neoplasm (MPN) has been increasing with time. Partial Tandem Duplications of the MLL gene (MLL-PTD) has been reported in de novo acute myeloid leukemia (AML), but not in MPN blast phase. The post-MPN AML developed adverse clinical outcomes, which showed no noticeable improvement over the past 15 years. Therefore, the mechanisms and therapeutic approaches of post-MPN AML need to be deeply studied.
PATIENT CONCERNS: In this study, we present a JAK2V617F positive MPN patient who experienced fatigue and splenomegaly, transforming into JAK2V617F negative AML.
DIAGNOSES: A diagnosis of acute monocytic leukemia was made in MPN blast phase.
INTERVENTIONS: The patient received chemotherapy and allogeneic hematopoietic stem cell transplantation (Allo-SCT).
OUTCOMES: The patient achieved complete remission twice, but relapsed twice. Relapse-free survival was only 3 months. She died about 24 months after her diagnosis.
LESSONS: MLL-PTD occurs in the progression of JAK2V617F positive MPN into JAK2V617F negative AML, which may be a novel mechanism of MPN blast phase and helpful for post-MPN AML diagnosis. Allo-SCT may be a good choice for post-MPN AML with MLL-PTD. More therapeutic strategies need to be explored for a better prognosis in these patients.

Bariar B, Vestal CG, Deem B, et al.
Bioflavonoids promote stable translocations between MLL-AF9 breakpoint cluster regions independent of normal chromosomal context: Model system to screen environmental risks.
Environ Mol Mutagen. 2019; 60(2):154-167 [PubMed] Article available free on PMC after 01/03/2020 Related Publications
Infant acute leukemias are aggressive and characterized by rapid onset after birth. The majority harbor translocations involving the MLL gene with AF9 as one of its most common fusion partners. MLL and AF9 loci contain breakpoint cluster regions (bcrs) with sequences hypothesized to be targets of topoisomerase II inhibitors that promote translocation formation. Overlap of MLL bcr sequences associated with both infant acute leukemia and therapy-related leukemia following exposure to the topoisomerase II inhibitor etoposide led to the hypothesis that exposure during pregnancy to biochemically similar compounds may promote infant acute leukemia. We established a reporter system to systematically quantitate and stratify the potential for such compounds to promote chromosomal translocations between the MLL and AF9 bcrs analogous to those in infant leukemia. We show bioflavonoids genistein and quercetin most biochemically similar to etoposide have a strong association with MLL-AF9 bcr translocations, while kaempferol, fisetin, flavone, and myricetin have a weak but consistent association, and other compounds have a minimal association in both embryonic stem (ES) and hematopoietic stem cell (HSC) populations. The frequency of translocations induced by bioflavonoids at later stages of myelopoiesis is significantly reduced by more than one log. The MLL and AF9 bcrs are sensitive to these agents and recombinogenic independent of their native context suggesting bcr sequences themselves are drivers of illegitimate DNA repair reactions and translocations, not generation of functional oncogenic fusions. This system provides for rapid systematic screening of relative risk, dose dependence, and combinatorial impact of multitudes of dietary and environmental exposures on MLL-AF9 translocations. Environ. Mol. Mutagen. 60: 154-167, 2019. © 2018 Wiley Periodicals, Inc.

Sun Y, Zhou B, Mao F, et al.
HOXA9 Reprograms the Enhancer Landscape to Promote Leukemogenesis.
Cancer Cell. 2018; 34(4):643-658.e5 [PubMed] Article available free on PMC after 08/10/2019 Related Publications
Aberrant expression of HOXA9 is a prominent feature of acute leukemia driven by diverse oncogenes. Here we show that HOXA9 overexpression in myeloid and B progenitor cells leads to significant enhancer reorganizations with prominent emergence of leukemia-specific de novo enhancers. Alterations in the enhancer landscape lead to activation of an ectopic embryonic gene program. We show that HOXA9 functions as a pioneer factor at de novo enhancers and recruits CEBPα and the MLL3/MLL4 complex. Genetic deletion of MLL3/MLL4 blocks histone H3K4 methylation at de novo enhancers and inhibits HOXA9/MEIS1-mediated leukemogenesis in vivo. These results suggest that therapeutic targeting of HOXA9-dependent enhancer reorganization can be an effective therapeutic strategy in acute leukemia with HOXA9 overexpression.

Chu SH, Song EJ, Chabon JR, et al.
Inhibition of MEK and ATR is effective in a B-cell acute lymphoblastic leukemia model driven by
Blood Adv. 2018; 2(19):2478-2490 [PubMed] Article available free on PMC after 08/10/2019 Related Publications
Infant B-cell acute lymphoblastic leukemias (B-ALLs) that harbor

Koh J, Nam SK, Roh H, et al.
Somatic mutational profiles of stage II and III gastric cancer according to tumor microenvironment immune type.
Genes Chromosomes Cancer. 2019; 58(1):12-22 [PubMed] Related Publications
We aimed to determine somatic mutational profiles of stage II/III gastric cancers (GCs) according to their tumor microenvironment immune types (TMITs), which classify cancer based on co-assessment of PD-L1 expression and CD8

Pan W, Zhang N, Liu W, et al.
The long noncoding RNA
J Biol Chem. 2018; 293(44):17154-17165 [PubMed] Article available free on PMC after 02/11/2019 Related Publications
Long noncoding RNAs (lncRNAs) are vital players in cancers, including hepatocellular carcinoma (HCC). We previously identified an lncRNA,

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