Identification of truncated RUNX1 and RUNX1-PRDM16 fusion transcripts in a case of t(1;21)(p36;q22)-positive therapy-related AML

Comprehensive genomic characterization of hematologic malignancies at a pediatric tertiary care center

Despite the increasing availability of comprehensive next generation sequencing (NGS), its role in characterizing pediatric hematologic malignancies remains undefined. We describe findings from comprehensive genomic profiling of hematologic malignancies at a pediatric tertiary care center. Patients enrolled on a translational research protocol to aid in cancer diagnosis, prognostication, treatment, and detection of cancer predisposition. Disease-involved samples underwent exome and RNA sequencing and analysis for single nucleotide variation, insertion/deletions, copy number alteration, structural variation, fusions, and gene expression. Twenty-eight patients with hematologic malignancies were nominated between 2018-2021. Eighteen individuals received both germline and somatic sequencing; two received germline sequencing only. Germline testing identified patients with cancer predisposition syndromes and non-cancer carrier states. Fifteen patients (15/18, 83%) had cancer-relevant somatic findings. Potential therapeutic targets were identified in seven patients (7/18, 38.9%); three (3/7, 42.9%) received targeted therapies and remain in remission an average of 47 months later.

Unravelling the function of prdm16 in human tumours: A comparative analysis of haematologic and solid tumours

Extensive research has shown that PR domain 16 (PRDM16) plays a critical role in adipose tissue metabolism, including processes such as browning and thermogenesis of adipocytes, beigeing of adipocytes, and adipogenic differentiation of myoblasts. These functions have been associated with diseases such as obesity and diabetes. Additionally, PRDM16 has been correlated with various other conditions, including migraines, heterochromatin abnormalities, metabolic syndrome, cardiomyopathy, sarcopenia, nonsyndromic cleft lip, and essential hypertension, among others. However, there is currently no systematic or comprehensive conclusion regarding the mechanism of PRDM16 in human tumours, including haematologic and solid tumours. The aim of this review is to provide an overview of the research progress on PRDM16 in haematologic and solid tumours by incorporating recent literature findings. Furthermore, we explore the prospects of PRDM16 in the precise diagnosis and treatment of human haematologic and solid tumours.

Neoplasia-associated Chromosome Translocations Resulting in Gene Truncation

Chromosomal translocations in cancer as well as benign neoplasias typically lead to the formation of fusion genes. Such genes may encode chimeric proteins when two protein-coding regions fuse in-frame, or they may result in deregulation of genes via promoter swapping or translocation of the gene into the vicinity of a highly active regulatory element. A less studied consequence of chromosomal translocations is the fusion of two breakpoint genes resulting in an out-of-frame chimera. The breaks then occur in one or both protein-coding regions forming a stop codon in the chimeric transcript shortly after the fusion point. Though the latter genetic events and mechanisms at first awoke little research interest, careful investigations have established them as neither rare nor inconsequential. In the present work, we review and discuss the truncation of genes in neoplastic cells resulting from chromosomal rearrangements, especially from seemingly balanced translocations.

Transcriptome analysis offers a comprehensive illustration of the genetic background of pediatric acute myeloid leukemia

Recent advances in the genetic understanding of acute myeloid leukemia (AML) have improved clinical outcomes in pediatric patients. However, ∼40% of patients with pediatric AML relapse, resulting in a relatively low overall survival rate of ∼70%. The objective of this study was to reveal the comprehensive genetic background of pediatric AML. We performed transcriptome analysis (RNA sequencing [RNA-seq]) in 139 of the 369 patients with de novo pediatric AML who were enrolled in the Japanese Pediatric Leukemia/Lymphoma Study Group AML-05 trial and investigated correlations between genetic aberrations and clinical information. Using RNA-seq, we identified 54 in-frame gene fusions and 1 RUNX1 out-of-frame fusion in 53 of 139 patients. Moreover, we found at least 258 gene fusions in 369 patients (70%) through reverse transcription polymerase chain reaction and RNA-seq. Five gene rearrangements were newly identified, namely, NPM1-CCDC28A, TRIP12-NPM1, MLLT10-DNAJC1, TBL1XR1-RARB, and RUNX1-FNBP1. In addition, we found rare gene rearrangements, namely, MYB-GATA1, NPM1-MLF1, ETV6-NCOA2, ETV6-MECOM, ETV6-CTNNB1, RUNX1-PRDM16, RUNX1-CBFA2T2, and RUNX1-CBFA2T3. Among the remaining 111 patients, KMT2A-PTD, biallelic CEBPA, and NPM1 gene mutations were found in 11, 23, and 17 patients, respectively. These mutations were completely mutually exclusive with any gene fusions. RNA-seq unmasked the complexity of gene rearrangements and mutations in pediatric AML. We identified potentially disease-causing alterations in nearly all patients with AML, including novel gene fusions. Our results indicated that a subset of patients with pediatric AML represent a distinct entity that may be discriminated from their adult counterparts. Based on these results, risk stratification should be reconsidered.

Multifaceted Role of PRDM Proteins in Human Cancer

The PR/SET domain family (PRDM) comprise a family of genes whose protein products share a conserved N-terminal PR [PRDI-BF1 (positive regulatory domain I-binding factor 1) and RIZ1 (retinoblastoma protein-interacting zinc finger gene 1)] homologous domain structurally and functionally similar to the catalytic SET [Su(var)3-9, enhancer-of-zeste and trithorax] domain of histone methyltransferases (HMTs). These genes are involved in epigenetic regulation of gene expression through their intrinsic HMTase activity or via interactions with other chromatin modifying enzymes. In this way they control a broad spectrum of biological processes, including proliferation and differentiation control, cell cycle progression, and maintenance of immune cell homeostasis. In cancer, tumor-specific dysfunctions of PRDM genes alter their expression by genetic and/or epigenetic modifications. A common characteristic of most PRDM genes is to encode for two main molecular variants with or without the PR domain. They are generated by either alternative splicing or alternative use of different promoters and play opposite roles, particularly in cancer where their imbalance can be often observed. In this scenario, PRDM proteins are involved in cancer onset, invasion, and metastasis and their altered expression is related to poor prognosis and clinical outcome. These functions strongly suggest their potential use in cancer management as diagnostic or prognostic tools and as new targets of therapeutic intervention.

PRDM16 isoforms differentially regulate normal and leukemic hematopoiesis and inflammatory gene signature

PRDM16 is a transcriptional coregulator involved in translocations in acute myeloblastic leukemia (AML), myelodysplastic syndromes, and T acute lymphoblastic leukemia that is highly expressed in and required for the maintenance of hematopoietic stem cells (HSCs), and can be aberrantly expressed in AML. Prdm16 is expressed as full-length (fPrdm16) and short (sPrdm16) isoforms, the latter lacking the N-terminal PR domain. The role of both isoforms in normal and malignant hematopoiesis is unclear. We show here that fPrdm16 was critical for HSC maintenance, induced multiple genes involved in GTPase signaling, and repressed inflammation, while sPrdm16 supported B cell development biased toward marginal zone B cells and induced an inflammatory signature. In a mouse model of human MLL-AF9 leukemia, fPrdm16 extended latency, while sPrdm16 shortened latency and induced a strong inflammatory signature, including several cytokines and chemokines that are associated with myelodysplasia and with a worse prognosis in human AML. Finally, in human NPM1-mutant and in MLL-translocated AML, high expression of PRDM16, which negatively impacts outcome, was associated with inflammatory gene expression, thus corroborating the mouse data. Our observations demonstrate distinct roles for Prdm16 isoforms in normal HSCs and AML, and identify sPrdm16 as one of the drivers of prognostically adverse inflammation in leukemia.

Acute myeloid leukemia with translocation (1;21)

Advancement in genetic and molecular biology techniques has greatly helped our understanding of various diseases, especially hematological disorders. We describe a case of primary myelofibrosis (PMF) that transformed into acute myeloid leukemia with a very rare and unusual genetic translocation of (1;21). There are only five reported cases of this translocation in acute myeloid leukemia (AML) or myelodysplastic syndrome but none of them transformed from PMF. This case not only highlights the importance of rare genetic translocations but also provides the natural history of the disease and its poor prognosis. To the best of our knowledge our patient is the first reported case of AML transformed from PMF to have this unique translocation of (1;21).

RUNX1 truncation resulting from a cryptic and novel t(6;21)(q25;q22) chromosome translocation in acute myeloid leukemia: A case report

Fluorescence in situ hybridization examination of a pediatric AML patient whose bone marrow cells carried trisomy 4 and FLT3-ITD mutation, demonstrated that part of the RUNX1 probe had unexpectedly moved to chromosome band 6q25 indicating a cryptic t(6;21)(q25;q22) translocation. RNA sequencing showed fusion of exon 7 of RUNX1 with an intergenic sequence of 6q25 close to the MIR1202 locus, something that was verified by RT-PCR together with Sanger sequencing. The RUNX1 fusion transcript encodes a truncated protein containing the Runt homology domain responsible for both heterodimerization with CBFB and DNA binding, but lacking the proline-, serine-, and threonine-rich (PST) region which is the transcription activation domain at the C terminal end. Which genetic event (+4, FLT3-ITD, t(6;21)-RUNX1 truncation or other, undetected acquired changes) was more pathogenetically important in the present case of AML, remains unknown. The case illustrates that submicroscopic chromosomal rearrangements may accompany visible numerical changes and perhaps should be actively looked for whenever a single trisomy is found. An active search for them may provide both pathogenetic and prognostic novel information.

The Multifaceted Roles of PRDM16: Adipose Biology and Beyond

The PRDM [PRDI-BFI (positive regulatory domain I-binding factor 1) and RIZ1 (retinoblastoma protein-interacting zinc finger gene 1) homologous domain containing] protein family is involved in a spectrum of biological processes including cell fate determination and development. These proteins regulate transcription through intrinsic chromatin-modifying activity or by complexing with histone-modifying or other nuclear proteins. Studies have indicated crucial roles for PRDM16 in the determination and function of brown and beige fat as well as in hematopoiesis and cardiac development, highlighting the importance of PRDM16 in developmental processes in different tissues. More recently, PRDM16 mutations were also identified in humans. The substantial progress in understanding the mechanism underlying the action of PRDM16 in adipose biology may have relevance to other PRDM family members, and this new knowledge has the potential to be exploited for therapeutic benefit.

RUNX1 translocations and fusion genes in malignant hemopathies

The RUNX1 gene, located in chromosome 21q22, is crucial for the establishment of definitive hematopoiesis and the generation of hematopoietic stem cells in the embryo. It contains a 'Runt homology domain' as well as transcription activation and inhibition domains. RUNX1 can act as activator or repressor of target gene expression depending upon the large number of transcription factors, coactivators and corepressors that interact with it. Translocations involving chromosomal band 21q22 are regularly identified in leukemia patients. Most of them are associated with a rearrangement of RUNX1. Indeed, at present, 55 partner chromosomal bands have been described but the partner gene has solely been identified in 21 translocations at the molecular level. All the translocations that retain Runt homology domains but remove the transcription activation domain have a leukemogenic effect by acting as dominant negative inhibitors of wild-type RUNX1 in transcription activation.

Myelodysplasia and leukemia of Fanconi anemia are associated with a specific pattern of genomic abnormalities that includes cryptic RUNX1/AML1 lesions

Fanconi anemia (FA) is a genetic condition associated with bone marrow (BM) failure, myelodysplasia (MDS), and acute myeloid leukemia (AML). We studied 57 FA patients with hypoplastic or aplastic anemia (n = 20), MDS (n = 18), AML (n = 11), or no BM abnormality (n = 8). BM samples were analyzed by karyotype, high-density DNA arrays with respect to paired fibroblasts, and by selected oncogene sequencing. A specific pattern of chromosomal abnormalities was found in MDS/AML, which included 1q+ (44.8%), 3q+ (41.4%), -7/7q (17.2%), and 11q- (13.8%). Moreover, cryptic RUNX1/AML1 lesions (translocations, deletions, or mutations) were observed for the first time in FA (20.7%). Rare mutations of NRAS, FLT3-ITD, MLL-PTD, ERG amplification, and ZFP36L2-PRDM16 translocation, but no TP53, TET2, CBL, NPM1, and CEBPα mutations were found. Frequent homozygosity regions were related not to somatic copy-neutral loss of heterozygosity but to consanguinity, suggesting that homologous recombination is not a common progression mechanism in FA. Importantly, the RUNX1 and other chromosomal/genomic lesions were found at the MDS/AML stages, except for 1q+, which was found at all stages. These data have implications for staging and therapeutic managing in FA patients, and also to analyze the mechanisms of clonal evolution and oncogenesis in a background of genomic instability and BM failure.

[Relationship between the expression of PRDM14 in non-small cell lung cancer and the clinicopathologic characteristics]

背景与目的

锌指蛋白转录抑制因子(positive regulatory domain zinc finger protein, PRDM)是一个有关人类肿瘤形成的转录调节因子家族，在细胞分化和恶性变中发挥重要作用。PRDM14是PRDM家族的成员之一。本研究的目的是检测PRDM14在非小细胞肺癌组织中的表达情况并探讨其与非小细胞肺癌的临床病理因素的关系。

方法

采用免疫组织化学方法检测70例非小细胞肺癌标本和7例癌旁组织中PRDM14的表达。采用Western blot方法检测42例非小细胞肺癌组织和癌旁肺组织中PRDM14蛋白的表达。

结果

7例癌旁肺组织中PRDM14弱表达，在70例非小细胞肺癌组织标本中，有8例为PRDM14阴性表达(11.43%)，9例为PRDM14弱阳性表达(12.86%)，36例PRDM14阳性表达(51.43%)，有17例PRDM14强阳性表达(24.29%)，PRDM14的表达情况与非小细胞肺癌的分化程度(P=0.046)和组织学类型(P=0.047)有关，PRDM14在高分化腺癌、鳞癌中表达最高，在中分化腺癌、鳞癌中表达次之，在低分化腺癌、鳞癌表达最低，PRDM14在腺癌中的表达高于鳞癌。Western blot结果表明PRDM14的蛋白在癌旁肺组织和肺腺癌、鳞癌组织的表达水平存在显著差异，PRDM14在非小细胞肺癌组织中的表达水平高于癌旁肺组织(P＜0.001)，而且与非小细胞肺癌的分化程度有关(P=0.017)，在高、中分化腺癌、鳞癌中的表达高于在低分化腺癌、鳞癌中的表达。

结论

PRDM14在癌旁肺组织中低表达，在非小细胞肺癌组织中高表达，其表达水平与非小细胞肺癌的分化、组织学类型有关，可能在非小细胞肺癌的发生发展中发挥作用。

CLCA2, a novel RUNX1 partner gene in a therapy-related leukemia with t(1;21)(p22;q22)

The RUNX1 gene is frequently rearranged in de novo and therapy-related leukemia. In the present study, we identified the CLCA2 gene as a novel fusion partner of RUNX1 in a case of therapy-related acute myeloid leukemia associated with t(1;21)(p22;q22). Reverse transcriptase-polymerase chain reaction analysis and sequencing revealed that the t(1;21) results in out-of-frame RUNX1-CLCA2 fusions. Alternative splicing generates at least six fusion transcripts, including a major transcript fusing RUNX1 exon 6 with CLCA2 exon 2. These out-of-frame fusions produce putative truncated RUNX1 isoforms retaining the DNA binding Runt domain but not the transcriptional regulatory domain of RUNX1. No mutations were found in the exons encoding the Runt and C-terminal domains of the nonrearranged RUNX1 gene. Similar to truncated RUNX1 isoforms previously described, these shortened products could act as dominant negative inhibitors of RUNX1-dependent transactivation. CLCA2 is a breast tumor suppressor gene that encodes a member of the calcium-activated chloride channel family and is involved for the first time in a chromosomal translocation. The RUNX1-CLCA2 fusion is another example of out-of-frame fusion generating truncated RUNX1 isoforms that represent a recurrent molecular mechanism in RUNX1-related leukemias.

The zinc finger SET domain gene Prdm14 is overexpressed in lymphoblastic lymphomas with retroviral insertions at Evi32

BACKGROUND

AKXD recombinant inbred strains of mice have proven to be very useful in the identification of potential oncogenes and tumor suppressors involved in the development of lymphoid and myeloid malignancies. In these tumors, the hematopoietic insertion of an active AKV murine leukemia virus (MuLV) is associated with the onset of disease. Common sites of retroviral insertion (CIS) identify genes causally associated with the development or initiation of lymphoma.

METHODOLOGY

In the present study, we analyzed a previously uncharacterized CIS, Ecotropic Viral Integration Site 32 (Evi32), which is located on mouse chromosome 1. We analyzed candidate genes in the region to identify those involved in Evi32 mediated oncogenesis.

RESULTS

Here we show that proviral insertion at Evi32 correlates with significant overexpression of a putative transcription factor, PR-domain containing 14 (Prdm14). Tumors with insertions at Evi32 are consistently lymphoid in nature. Prdm14 is normally expressed early in embryonic development with the highest expression in undifferentiated embryonic stem (ES) cells. This study implicates Prdm14 as a proto-oncogene involved in lymphoblastic lymphoma formation.

Overexpression of sPRDM16 coupled with loss of p53 induces myeloid leukemias in mice

Transgenic expression of the abnormal products of acute myeloid leukemia-associated (AML-associated) primary chromosomal translocations in hematopoietic stem/progenitor cells initiates leukemogenesis in mice, yet additional mutations are needed for leukemia development. We report here aberrant expression of PR domain containing 16 (PRDM16) in AML cells with either translocations of 1p36 or normal karyotype. These carried, respectively, relatively high prevalence of mutations in the TP53 tumor suppressor gene and in the nucleophosmin (NPM) gene, which regulates p53. Two protein isoforms are expressed from PRDM16, which differ in the presence or absence of the PR domain. Overexpression of the short isoform, sPRDM16, in mouse bone marrow induced AML with full penetrance, but only in the absence of p53. The mouse leukemias were characterized by multilineage cellular abnormalities and megakaryocyte dysplasia, a common feature of human AMLs with 1p36 translocations or NPM mutations. Overexpression of sPRDM16 increased the pool of HSCs in vivo, and in vitro blocked myeloid differentiation and prolonged progenitor life span. Loss of p53 augmented the effects of sPRDM16 on stem cell number and induced immortalization of progenitors. Thus, overexpression of sPRDM16 induces abnormal growth of stem cells and progenitors and cooperates with disruption of the p53 pathway in the induction of myeloid leukemia.

Genome-wide mapping and characterization of hypomethylated sites in human tissues and breast cancer cell lines

We have developed a method for mapping unmethylated sites in the human genome based on the resistance of TspRI-digested ends to ExoIII nuclease degradation. Digestion with TspRI and methylation-sensitive restriction endonuclease HpaII, followed by ExoIII and single-strand DNA nuclease allowed removal of DNA fragments containing unmethylated HpaII sites. We then used array comparative genomic hybridization (CGH) to map the sequences depleted by these procedures in human genomes derived from five human tissues, a primary breast tumor, and two breast tumor cell lines. Analysis of methylation patterns of the normal tissue genomes indicates that the hypomethylated sites are enriched in the 5' end of widely expressed genes, including promoter, first exon, and first intron. In contrast, genomes of the MCF-7 and MDA-MB-231 cell lines show extensive hypomethylation in the intragenic and intergenic regions whereas the primary tumor exhibits a pattern between those of the normal tissue and the cell lines. A striking characteristic of tumor cell lines is the presence of megabase-sized hypomethylated zones. These hypomethylated zones are associated with large genes, fragile sites, evolutionary breakpoints, chromosomal rearrangement breakpoints, tumor suppressor genes, and with regions containing tissue-specific gene clusters or with gene-poor regions containing novel tissue-specific genes. Correlation with microarray analysis shows that genes with a hypomethylated sequence 2 kb up- or downstream of the transcription start site are highly expressed, whereas genes with extensive intragenic and 3' untranslated region (UTR) hypomethylation are silenced. The method described herein can be used for large-scale screening of changes in the methylation pattern in the genome of interest.

RUNX1 DNA-binding mutations and RUNX1-PRDM16 cryptic fusions in BCR-ABL+ leukemias are frequently associated with secondary trisomy 21 and may contribute to clonal evolution and imatinib resistance

Acquired molecular abnormalities (mutations or chromosomal translocations) of the RUNX1 transcription factor gene are frequent in acute myeloblastic leukemias (AMLs) and in therapy-related myelodysplastic syndromes, but rarely in acute lymphoblastic leukemias (ALLs) and chronic myelogenous leukemias (CMLs). Among 18 BCR-ABL+ leukemias presenting acquired trisomy of chromosome 21, we report a high frequency (33%) of recurrent point mutations (4 in myeloid blast crisis [BC] CML and one in chronic phase CML) within the DNA-binding region of RUNX1. We did not found any mutation in de novo BCR-ABL+ ALLs or lymphoid BC CML. Emergence of the RUNX1 mutations was detected at diagnosis or before the acquisition of trisomy 21 during disease progression. In addition, we also report a high frequency of cryptic chromosomal RUNX1 translocation to a novel recently described gene partner, PRDM16 on chromosome 1p36, for 3 (21.4%) of 14 investigated patients: 2 myeloid BC CMLs and, for the first time, 1 therapy-related BCR-ABL+ ALL. Two patients presented both RUNX1 mutations and RUNX1-PRDM16 fusion. These events are associated with a short survival and support the concept of a cooperative effect of BCR-ABL with molecular RUNX1 abnormalities on the differentiation arrest phenotype observed during progression of CML and in BCR-ABL+ ALL.

Leukemogenesis of the EVI1/MEL1 gene family

Leukemia is a group of monoclonal diseases that arise from hematopoietic stem and progenitor cells in the bone marrow or other hematopoietic organs. Retroviral infections are one of the major events leading to leukemogenesis in mice, because retroviruses can induce hematopoietic disease via the insertional mutagenesis of oncogenes; therefore, the cloning of viral-integration sites in murine leukemia has provided valuable molecular tags for oncogene discovery. Transcription of the murine gene ecotropic viral-integration site 1 (Evi1) is activated by nearby viral integration. In humans, the Evi1 homologue EVI1 is activated by chromosomal translocations. This review discusses the roles of the overexpression of EVI1/MEL1 gene family members in leukemogenesis, the relationships of various translocations in EVI1 overexpression, and the importance of PR domains in tumor suppression and oncogenesis. The functions of EVI1/MEL1 members as transcription factors and the concept of EVI1-positive leukemia as a stem cell disease are also reviewed.

Epigenetic regulation of protein-coding and microRNA genes by the Gfi1-interacting tumor suppressor PRDM5

Gfi1 transcriptionally governs hematopoiesis, and its mutations produce neutropenia. In an effort to identify Gfi1-interacting proteins and also to generate new candidate genes causing neutropenia, we performed a yeast two-hybrid screen with Gfi1. Among other Gfi1-interacting proteins, we identified a previously uncharacterized member of the PR domain-containing family of tumor suppressors, PRDM5. PRDM5 has 16 zinc fingers, and we show that it acts as a sequence-specific, DNA binding transcription factor that targets hematopoiesis-associated protein-coding and microRNA genes, including many that are also targets of Gfi1. PRDM5 epigenetically regulates transcription similarly to Gfi1: it recruits the histone methyltransferase G9a and class I histone deacetylases to its target gene promoters and demonstrates repressor activity on synthetic reporters; on endogenous target genes, however, it functions as an activator, in addition to a repressor. Interestingly, genes that PRDM5 activates, as opposed to those it represses, are also targets of Gfi1, suggesting a competitive mechanism through which two repressors could cooperate in order to become transcriptional activators. In neutropenic patients, we identified PRDM5 protein sequence variants perturbing transcriptional function, suggesting a potentially important role in hematopoiesis.

Fusion gene-mediated truncation ofRUNX1 as a potential mechanism underlying disease progression in the 8p11 myeloproliferative syndrome

The 8p11 myeloproliferative syndrome (EMS) is a chronic myeloproliferative disorder molecularly characterized by fusion of various 5' partner genes to the 3' part of the fibroblast growth factor receptor 1 (FGFR1) gene at 8p, resulting in constitutive activation of the tyrosine kinase activity contained within FGFR1. EMS is associated with a high risk of transformation to acute myeloid leukemia (AML), but the mechanisms underlying the disease progression are unknown. In the present study, we have investigated a case of EMS harboring a t(8;22)(p11;q11)/BCR-FGFR1 rearrangement as well as a t(9;21)(q34;q22) at the time of AML transformation. FISH and RT-PCR analyses revealed that the t(9;21) leads to a fusion gene consisting of the 5' part of RUNX1 (exons 1-4) fused to repetitive sequences of a gene with unknown function on chromosome 9, adding 70 amino acids to RUNX1 exon 4. The t(9;21) hence results in a truncation of RUNX1. No point mutations were found in the other RUNX1 allele. The most likely functional outcome of the rearrangement was haploinsufficiency of RUNX1, which thus may be one mechanism by which EMS transforms to AML.