Research IndicatorsGraph generated 17 August 2015 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 17 August, 2015 using data from PubMed, MeSH and CancerIndex
Specific Cancers (6)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
COSMIC, Sanger Institute
Somatic mutation information and related details
TICdb, Universidad de Navarra
Search the database of Translocation breakpoints In Cancer for "MECOM"
Search the Epigenomics database and view relevant gene tracks of samples.
Latest Publications: MECOM (cancer-related)
Jo A, Mitani S, Shiba N, et al.High expression of EVI1 and MEL1 is a compelling poor prognostic marker of pediatric AML.
Leukemia. 2015; 29(5):1076-83 [PubMed
] Related Publications
EVI1 and MEL1 are homolog genes whose transcriptional activations by chromosomal translocations are known in small subsets of leukemia. From gene expression profiling data of 130 Japanese pediatric acute myeloid leukemia (AML) patients, we found that EVI1 and MEL1 were overexpressed in ~30% of patients without obvious translocations of these gene loci, and that their high expression was significantly associated with inferior survival. High EVI1 expression was detected mainly in myelomonocytic-lineage (designated as e-M4/M5 subtype) leukemia with MLL rearrangements and in megakaryocytic-lineage (designated as e-M7 subtype) leukemia, and its prognostic association was observed in the e-M4/M5 subtype but not in the e-M7 subtype. On the other hand, high MEL1 expression was detected in myelocytic-lineage (designated as e-M0/M1/M2 subtype) and e-M4/M5 subtype leukemia without MLL rearrangements, and its prognostic association was independent from the subtypes. Because of their subtype-dependent and mutually exclusive expression, a combined evaluation of their high expression enabled a clear distinction of patients with inferior survival (P<0.00001 in event-free survival (EFS) and overall survival (OS)). This association was confirmed by quantitative reverse transcription PCR analysis of an independent cohort of 81 patients (P=0.00017 in EFS, P=0.00028 in OS). We propose that the combined estimation of EVI1 and MEL1 expression will be an effective method to predict the prognosis of pediatric AML.
Myeloid malignancies bearing chromosomal inv(3)/t(3;3) abnormalities are among the most therapy-resistant leukemias. Deregulated expression of EVI1 is the molecular hallmark of this disease; however, the genome-wide spectrum of cooperating mutations in this disease subset has not been systematically elucidated. Here, we show that 98% of inv(3)/t(3;3) myeloid malignancies harbor mutations in genes activating RAS/receptor tyrosine kinase (RTK) signaling pathways. In addition, hemizygous mutations in GATA2, as well as heterozygous alterations in RUNX1, SF3B1, and genes encoding epigenetic modifiers, frequently co-occur with the inv(3)/t(3;3) aberration. Notably, neither mutational patterns nor gene expression profiles differ across inv(3)/t(3;3) acute myeloid leukemia, chronic myeloid leukemia, and myelodysplastic syndrome cases, suggesting recognition of inv(3)/t(3;3) myeloid malignancies as a single disease entity irrespective of blast count. The high incidence of activating RAS/RTK signaling mutations may provide a target for a rational treatment strategy in this high-risk patient group.
The genetic and transcriptional signature of EVI1 (ecotropic viral integration site 1)-rearranged (EVI1-r) acute myeloid leukemias (AMLs) remains poorly defined. We performed RNA sequencing of 12 EVI1-r AMLs and compared the results with those of other AML subtypes (n = 139) and normal CD34(+) cells (n = 17). Results confirm high frequencies of RAS and other activated signaling mutations (10/12 AMLs) and identify new recurrent mutations in splicing factors (5/12 AMLs in SF3B1 and 2/12 AMLs in U2AF1), IKZF1 (3/12 AMLs), and TP53 (3/12 AMLs). Mutations in IKZF1, a gene located on chromosome 7, and monosomy 7 are mutually exclusive in this disease. Moreover IKZF1 expression is halved in monosomy 7 leukemias. EVI-r AMLs are also characterized by a unique transcriptional signature with high expression levels of MECOM, PREX2, VIP, MYCT1, and PAWR. Our results suggest that EVI1-r AMLs could be molecularly defined by specific transcriptomic anomalies and a hitherto unseen mutational pattern. Larger patient cohorts will better determine the frequency of these events.
Wang TY, Huang YP, Ma PCorrelations of common polymorphism of EVI-1 gene targeted by miRNA-206/133b with the pathogenesis of breast cancer.
Tumour Biol. 2014; 35(9):9255-62 [PubMed
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The aim of this study was to identify the correlations of a common polymorphism (rs6774494 A > G) in the EVI-1 gene targeted by micro-RNA (miRNA)-206/133b with the pathogenesis of breast cancer (BC). A total of 196 unrelated ethnic Han Chinese women diagnosed with primary BC were consecutively recruited and 200 healthy controls were randomly selected from the same population-based cohort. Direct PCR sequencing assay was used to detection of rs6774494 A > G polymorphism in the EVI-1 gene. Real-time quantitative PCR (RT-PCR) analysis was performed to verify the alterations of the EVI1 messenger RNA (mRNA) levels. Kaplan-Meier analysis was used to investigate and to estimate the survival outcomes for each endpoint. All statistical analyses were performed with SPSS software (version 18.0, SPSS, Chicago, IL). Our results demonstrated that the carriers of EVI-1 AG genotype were more likely to develop BC when compared with the EVI-1 GG genotype (P = 0.034, OR = 1.26, 95% CI = 1.02 ∼ 1.57). In addition, it was found that patients with the G (AG + GG) allele of EVI-1 genetic variants were associated with higher risk of BC compared with the EVI-1 AA genotype (OR = 1.26, 95% CI = 1.02 ∼ 1.54, P = 0.028). The results of a subgroup analysis stratified by menopause revealed that in female post-menopause subgroup patients with the EVI-1 G allele were correlated with a higher risk of BC than those with the EVI-1 AA genotype (OR = 1.31, 95% CI = 1.00 ∼ 1.72, P = 0.054). Kaplan-Meier analyses suggested that carriers of the G allele (AG + GG) were associated with poorer overall survival (OS) and progression-free survival (PFS) compared with those with AA genotype (OS P = 0.042; PFS P = 0.036, respectively). The correlation analysis showed that EVI-1 mRNA levels were negatively associated with miRNA-206/133b levels in the carriers of the G allele (AG + GG) (r = -1.274, P < 0.05). Our findings provide evidence that the EVI-1 rs6774494 G > A polymorphism targeted by miRNA-206/133b may contribute to the pathogenesis of BC.
Pradhan AK, Halder A, Chakraborty SPhysical and functional interaction of the proto-oncogene EVI1 and tumor suppressor gene HIC1 deregulates Bcl-xL mediated block in apoptosis.
Int J Biochem Cell Biol. 2014; 53:320-8 [PubMed
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Ecotropic viral integration site 1 was originally identified as a retroviral integration site in murine leukemias. Several studies have established ecotropic viral integration site 1 as both a transcription factor and an interacting partner that presumably regulates gene expression. Using coimmunoprecipitation and fluorescence resonance energy transfer analysis, we found that the N-terminal domain of hypermethylated in cancer 1 interacts with the proximal set of zinc fingers of ecotropic viral integration site 1. This interaction not only abolishes the DNA binding activity of ecotropic viral integration site 1 but also disrupts the transcriptional activity of an anti-apoptotic gene promoter selectively targeted by ecotropic viral integration site 1. By using flow cytometry and western blotting, here we show that hypermethylated in cancer 1 can deregulate ecotropic viral integration site 1-mediated blockage of apoptosis. We hypothesize that therapeutic upregulation of hypermethylated in cancer 1 may provide an important means of targeting ecotropic viral integration site 1-positive cancers.
Blatt K, Herrmann H, Hoermann G, et al.Identification of campath-1 (CD52) as novel drug target in neoplastic stem cells in 5q-patients with MDS and AML.
Clin Cancer Res. 2014; 20(13):3589-602 [PubMed
] Related Publications
PURPOSE: The CD52-targeted antibody alemtuzumab induces major clinical responses in a group of patients with myelodysplastic syndromes (MDS). The mechanism underlying this drug effect remains unknown.
EXPERIMENTAL DESIGN: We asked whether neoplastic stem cells (NSC) in patients with MDS (n = 29) or acute myelogenous leukemia (AML; n = 62) express CD52.
RESULTS: As assessed by flow cytometry, CD52 was found to be expressed on NSC-enriched CD34(+)/CD38(-) cells in 8/11 patients with MDS and isolated del(5q). In most other patients with MDS, CD52 was weakly expressed or not detectable on NSC. In AML, CD34(+)/CD38(-) cells displayed CD52 in 23/62 patients, including four with complex karyotype and del(5q) and one with del(5q) and t(1;17;X). In quantitative PCR (qPCR) analyses, purified NSC obtained from del(5q) patients expressed CD52 mRNA. We were also able to show that CD52 mRNA levels correlate with EVI1 expression and that NRAS induces the expression of CD52 in AML cells. The CD52-targeting drug alemtuzumab, was found to induce complement-dependent lysis of CD34(+)/CD38(-)/CD52(+) NSC, but did not induce lysis in CD52(-) NSC. Alemtuzumab also suppressed engraftment of CD52(+) NSC in NSG mice. Finally, CD52 expression on NSC was found to correlate with a poor survival in patients with MDS and AML.
CONCLUSIONS: The cell surface target Campath-1 (CD52) is expressed on NSC in a group of patients with MDS and AML. CD52 is a novel prognostic NSC marker and a potential NSC target in a subset of patients with MDS and AML, which may have clinical implications and may explain clinical effects produced by alemtuzumab in these patients.
Relapse of chronic myeloid leukemia (CML) is triggered by stem cells with a reconstituting capacity similar to that of hematopoietic stem cells (HSCs) and CML stem cells are a source of resistance in drug therapy with tyrosine kinase inhibitors (TKIs). Ecotropic viral integration site 1 (EVI1), a key transcription factor in HSC regulation, is known to predict poor outcomes in myeloid malignancies, however, incapability of prospective isolation of EVI1-high leukemic cells precludes the functional evaluation of intraindividual EVI1-high cells. Introduction of CML into Evi1-internal ribosomal entry site (IRES)-green fluorescent protein (GFP) knock-in mice, a versatile HSC-reporter strain, enables us to separate Evi1-high CML cells from the individual. Evi1-IRES-GFP allele models of CML in chronic phase (CML-CP), by retroviral overexpression of BCR-ABL and by crossing BCR-ABL transgenic mice, revealed that Evi1 is predominantly enriched in the stem cell fraction and associated with an enhanced proliferative as well as a leukemia-initiating capacity and that Evi1-high CML-CP cells exhibit resistance to TKIs. Overexpressing BCR-ABL and NUP98-HOXA9 in Evi1-IRES-GFP knock-in mice to model CML in blast crisis (CML-BC), in which Evi1-high cells turned to be a major population as opposed to a minor population in CML-CP models, showed that Evi1-high CML-BC cells have a greater potential to recapitulate the disease and appear resistant to TKIs. Furthermore, given that Evi1 heterozygosity ameliorates CML-CP and CML-BC development and that the combination of Evi1 and BCR-ABL causes acute myeloid leukemia resembling CML-BC, Evi1 could regulate CML development as a potent driver. In addition, in human CML-CP cases, we show that EVI1 is highly expressed in stem cell-enriched CD34+CD38-CD90+ fraction at single-cell level. This is the first report to clarify directly that Evi1-high leukemic cells themselves possess the superior potential to Evi1-low cells in oncogenic self-renewal, which highlights the role of Evi1 as a valuable and a functional marker of CML stem cells.
The orchestration of transcriptional programs depends on proper gene-enhancer pairing. While much remains to be learned about this process in normal development, two recent studies in Cell (Gröschel and colleagues) and this issue of Cancer Cell (Yamazaki and colleagues) highlight how the genomic rearrangement of an enhancer plays a causal role in the onset of a leukemogenic program.
Chromosomal inversion between 3q21 and 3q26 results in high-risk acute myeloid leukemia (AML). In this study, we identified a mechanism whereby a GATA2 distal hematopoietic enhancer (G2DHE or -77-kb enhancer) is brought into close proximity to the EVI1 gene in inv(3)(q21;q26) inversions, leading to leukemogenesis. We examined the contribution of G2DHE to leukemogenesis by creating a bacterial artificial chromosome (BAC) transgenic model that recapitulates the inv(3)(q21;q26) allele. Transgenic mice harboring a linked BAC developed leukemia accompanied by EVI1 overexpression-neoplasia that was not detected in mice bearing the same transgene but that was missing the GATA2 enhancer. These results establish the mechanistic basis underlying the pathogenesis of a severe form of leukemia through aberrant expression of the EVI1 proto-oncogene.
Gröschel S, Sanders MA, Hoogenboezem R, et al.A single oncogenic enhancer rearrangement causes concomitant EVI1 and GATA2 deregulation in leukemia.
Cell. 2014; 157(2):369-81 [PubMed
] Related Publications
Chromosomal rearrangements without gene fusions have been implicated in leukemogenesis by causing deregulation of proto-oncogenes via relocation of cryptic regulatory DNA elements. AML with inv(3)/t(3;3) is associated with aberrant expression of the stem-cell regulator EVI1. Applying functional genomics and genome-engineering, we demonstrate that both 3q rearrangements reposition a distal GATA2 enhancer to ectopically activate EVI1 and simultaneously confer GATA2 functional haploinsufficiency, previously identified as the cause of sporadic familial AML/MDS and MonoMac/Emberger syndromes. Genomic excision of the ectopic enhancer restored EVI1 silencing and led to growth inhibition and differentiation of AML cells, which could be replicated by pharmacologic BET inhibition. Our data show that structural rearrangements involving the chromosomal repositioning of a single enhancer can cause deregulation of two unrelated distal genes, with cancer as the outcome.
Renneville A, Abdelali RB, Chevret S, et al.Clinical impact of gene mutations and lesions detected by SNP-array karyotyping in acute myeloid leukemia patients in the context of gemtuzumab ozogamicin treatment: results of the ALFA-0701 trial.
Oncotarget. 2014; 5(4):916-32 [PubMed
] Free Access to Full Article Related Publications
We recently showed that the addition of fractionated doses of gemtuzumab ozogamicin (GO) to standard chemotherapy improves clinical outcome of acute myeloid leukemia (AML) patients. In the present study, we performed mutational analysis of 11 genes (FLT3, NPM1, CEBPA, MLL, WT1, IDH1/2, RUNX1, ASXL1, TET2, DNMT3A), EVI1 overexpression screening, and 6.0 single-nucleotide polymorphism array (SNP-A) analysis in diagnostic samples of the 278 AML patients enrolled in the ALFA-0701 trial. In cytogenetically normal (CN) AML (n=146), 38% of the patients had at least 1 SNP-A lesion and 89% of the patients had at least 1 molecular alteration. In multivariate analysis, the independent predictors of higher cumulative incidence of relapse were unfavorable karyotype (P = 0.013) and randomization in the control arm (P = 0.007) in the whole cohort, and MLL partial tandem duplications (P = 0.014) and DNMT3A mutations (P = 0.010) in CN-AML. The independent predictors of shorter overall survival (OS) were unfavorable karyotype (P <0.001) and SNP-A lesion(s) (P = 0.001) in the whole cohort, and SNP-A lesion(s) (P = 0.006), DNMT3A mutations (P = 0.042) and randomization in the control arm (P = 0.043) in CN-AML. Interestingly, CN-AML patients benefited preferentially more from GO treatment as compared to AML patients with abnormal cytogenetics (hazard ratio for death, 0.52 versus 1.14; test for interaction, P = 0.04). Although the interaction test was not statistically significant, the OS benefit associated with GO treatment appeared also more pronounced in FLT3 internal tandem duplication positive than in negative patients.
Braun CJ, Boztug K, Paruzynski A, et al.Gene therapy for Wiskott-Aldrich syndrome--long-term efficacy and genotoxicity.
Sci Transl Med. 2014; 6(227):227ra33 [PubMed
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Wiskott-Aldrich syndrome (WAS) is characterized by microthrombocytopenia, immunodeficiency, autoimmunity, and susceptibility to malignancies. In our hematopoietic stem cell gene therapy (GT) trial using a γ-retroviral vector, 9 of 10 patients showed sustained engraftment and correction of WAS protein (WASP) expression in lymphoid and myeloid cells and platelets. GT resulted in partial or complete resolution of immunodeficiency, autoimmunity, and bleeding diathesis. Analysis of retroviral insertion sites revealed >140,000 unambiguous integration sites and a polyclonal pattern of hematopoiesis in all patients early after GT. Seven patients developed acute leukemia [one acute myeloid leukemia (AML), four T cell acute lymphoblastic leukemia (T-ALL), and two primary T-ALL with secondary AML associated with a dominant clone with vector integration at the LMO2 (six T-ALL), MDS1 (two AML), or MN1 (one AML) locus]. Cytogenetic analysis revealed additional genetic alterations such as chromosomal translocations. This study shows that hematopoietic stem cell GT for WAS is feasible and effective, but the use of γ-retroviral vectors is associated with a substantial risk of leukemogenesis.
Yee Ko JM, Dai W, Wun Wong EH, et al.Multigene pathway-based analyses identify nasopharyngeal carcinoma risk associations for cumulative adverse effects of TERT-CLPTM1L and DNA double-strand breaks repair.
Int J Cancer. 2014; 135(7):1634-45 [PubMed
] Related Publications
The genetic etiology of nasopharyngeal carcinoma (NPC) and mechanisms for inherited susceptibility remain unclear. To examine genetic risk factors for NPC, we hypothesized that heritable risk is attributable to cumulative effects of multiple common low-risk variants. With the premise that individual SNPs only confer subtle effects for cancer risk, a multigenic pathway-based approach was used to systematically examine associations between NPC genetic susceptibility with SNPs in genes in DNA repair pathways and from previously identified cancer genome-wide association study analyses. This case-control study covers 161 genes/loci and focuses on pathway-based analyses in 2,349 Hong Kong individuals, allowing stratification according to NPC familial status for meaningful association analysis. Three SNPs (rs401681, rs6774494 and rs3757318) corresponding to TERT/CLPTM1L (OR 95% CI = 0.77, 0.68-0.88), MDS1-EVI1 (OR 95% CI=0.79 0.69-0.89) and CCDC170 (OR 95% CI = 0.76, 0.66-0.86) conferred modest protective effects individually for NPC risk by the logistic regression analysis after multiple testing adjustment (p(Bonferroni) < 0.05). Stratification of NPC according to familial status identified rs2380165 in BLM (OR 95% CI = 1.49, 1.20-1.86, p(Bonferroni) < 0.05) association with family history-positive NPC (FH+ NPC) patients. Multiple SNPs pathway-based analysis revealed that the combined gene dosage effects for increasing numbers of unfavorable genotypes in TERT-CLPTM1L and double-strand break repair (DSBR) conferred elevated risk in FH+ and sporadic NPC patients (ORs per allele, 95% CIs = 1.37, 1.22-1.55, p(Bonferroni) = 5.00 × 10(-6); 1.17, 1.09-1.26, p(Bonferroni) = 4.58 × 10(-4) , respectively, in TERT/NHEJ pathways). Our data suggested cumulative increased NPC risk associations with TERT-CLPTM1L and DSBR pathways contribute to genetic susceptibility to NPC and have potential translational relevance for patient stratification and therapeutics.
Glass C, Wilson M, Gonzalez R, et al.The role of EVI1 in myeloid malignancies.
Blood Cells Mol Dis. 2014 Jun-Aug; 53(1-2):67-76 [PubMed
] Related Publications
The EVI1 oncogene at human chr 3q26 is rearranged and/or overexpressed in a subset of acute myeloid leukemias and myelodysplasias. The EVI1 protein is a 135 kDa transcriptional regulator with DNA-binding zinc finger domains. Here we provide a critical review of the current state of research into the molecular mechanisms by which this gene plays a role in myeloid malignancies. The major pertinent cellular effects are blocking myeloid differentiation and preventing cellular apoptosis, and several potential mechanisms for these phenomena have been identified. Evidence supports a role for EVI1 in inducing cellular quiescence, and this may contribute to the resistance to chemotherapy seen in patients with neoplasms that overexpress EVI1. Another isoform, MDS1-EVI1 (or PRDM3), encoded by the same locus as EVI1, harbors an N-terminal histone methyltransferase(HMT) domain; experimental findings indicate that this protein and its HMT activity are critical for the progression of a subset of AMLs, and this provides a potential target for therapeutic intervention.
Smith KA, Cowell IG, Zhang Y, et al.The role of topoisomerase II beta on breakage and proximity of RUNX1 to partner alleles RUNX1T1 and EVI1.
Genes Chromosomes Cancer. 2014; 53(2):117-28 [PubMed
] Related Publications
Rearrangements involving the RUNX1 gene account for approximately 15% of balanced translocations in therapy-related acute myeloid leukemia (t-AML) patients and are one of the most common genetic abnormalities observed in t-AML. Drugs targeting the topoisomerase II (TOP2) enzyme are implicated in t-AML; however, the mechanism is not well understood and to date a single RUNX1-RUNX1T1 t-AML breakpoint junction sequence has been published. Here we report an additional five breakpoint junction sequences from t-AML patients with the RUNX1- RUNX1T1 translocation. Using a leukemia cell line model, we show that TOP2 beta (TOP2B) is required for induction of RUNX1 chromosomal breaks by the TOP2 poison etoposide and that, while TOP2 alpha (TOP2A) and TOP2B proteins are both present on RUNX1 and RUNX1T1 chromatin, only the TOP2B enrichment reached significance following etoposide exposure at a region on RUNX1 where translocations occur. Furthermore, we demonstrate that TOP2B influences the separation between RUNX1 and two translocation partners (RUNX1T1 and EVI) in the nucleus of lymphoid cells. Specifically, we identified a TOP2B-dependent increase in the number of nuclei displaying juxtaposed RUNX1 and RUNX1T1 loci following etoposide treatment.
A subgroup of leukemogenic mixed-lineage leukemia (MLL) fusion proteins (MFPs) including MLL-AF9 activates the Mecom locus and exhibits extremely poor clinical prognosis. Mecom encodes EVI1 and MDS1-EVI1 (ME) proteins via alternative transcription start sites; these differ by the presence of a PRDI-BF1-RIZ1 (PR) domain with histone methyltransferase activity in the ME isoform. Using an ME-deficient mouse, we show that ME is required for MLL-AF9-induced transformation both in vitro and in vivo. And, although Nup98-HOXA9, MEIS1-HOXA9, and E2A-Hlf could transform ME-deficient cells, both MLL-AF9 and MLL-ENL were ineffective, indicating that the ME requirement is specific to MLL fusion leukemia. Further, we show that the PR domain is essential for MFP-induced transformation. These studies clearly indicate an essential role of PR-domain protein ME in MFP leukemia, suggesting that ME may be a novel target for therapeutic intervention for this group of leukemias.
Jiang MM, Gao L, Jing Y, et al.Rapid detection of AML1 associated fusion genes in patients with adult acute myeloid leukemia and its clinical significance.
Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2013; 21(4):821-9 [PubMed
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This study was aimed to detect the expression of AML1 fusion genes in the patients with adult acute myeloid leukemia (AML) and further to investigate their association with the progression and prognosis of AML. Bone marrow samples were collected from 168 patients with de novo adult AML, and the expression of AML1 ETO, AML1-EVI1, AML1-MDS1, AML1-MTG16, AML1-PRDM16, AML1-LRP16, AML1-CLCA2 and AML1-PRDX4 was analyzed by a novel multiplex nested RT-PCR. Positive samples and minimal residual disease were further examined by real-time fluorescent quantitative PCR. The results showed that the AML1 fusion genes were found in 10.7% (18/168) patients. Among them, AML1-ETO in 12 (7.1%) cases were detected, AML1-EVI1 in 2 cases (1.2%), and AML1-MDS1, AML1-MTG16, AML1-PRDM16, and AML1-CLCA2 in 1 case (0.6%) each were detected. Among the patients with AML1-ETO, 10 patients (10/12, 83.33%) achieved complete remission (CR) after one cycle of chemotherapy, while 2 patients achieved CR after 2 cycles of chemotherapy. The 2 patients with AML1-EVI1 failed to achieve CR after one cycle of chemotherapy. Patients with AML1-MDS1, AML1-MTG16, AML1-PRDM16, or AML1-CACL2 did not achieve CR after one cycle of chemotherapy. It is concluded that AML1 fusion genes are more frequent and can provide the molecular markers for diagnostics and prognosis evaluation of AML and for monitoring MRD.
Bard-Chapeau EA, Gunaratne J, Kumar P, et al.EVI1 oncoprotein interacts with a large and complex network of proteins and integrates signals through protein phosphorylation.
Proc Natl Acad Sci U S A. 2013; 110(31):E2885-94 [PubMed
] Free Access to Full Article Related Publications
Ecotropic viral integration site-1 (EVI1) is an oncogenic zinc finger transcription factor whose expression is frequently up-regulated in myeloid leukemia and epithelial cancers. To better understand the mechanisms underlying EVI1-associated disease, we sought to define the EVI1 interactome in cancer cells. By using stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomics, we could confidently assign 78 proteins as EVI1-interacting partners for FLAG-tagged EVI1. Subsequently, we showed that 22 of 27 tested interacting proteins could coimmunoprecipitate with endogenous EVI1 protein, which represented an 81.5% validation rate. Additionally, by comparing the stable isotope labeling by amino acids in cell culture (SILAC) data with high-throughput yeast two hybrid results, we showed that five of these proteins interacted directly with EVI1. Functional classification of EVI1-interacting proteins revealed associations with cellular transcription machinery; modulators of transcription; components of WNT, TGF-β, and RAS pathways; and proteins regulating DNA repair, recombination, and mitosis. We also identified EVI1 phosphorylation sites by MS analysis and showed that Ser538 and Ser858 can be phosphorylated and dephosphorylated by two EVI1 interactome proteins, casein kinase II and protein phosphatase-1α. Finally, mutations that impair EVI1 phosphorylation at these sites reduced EVI1 DNA binding through its C-terminal zinc finger domain and induced cancer cell proliferation. Collectively, these combinatorial proteomic approaches demonstrate that EVI1 interacts with large and complex networks of proteins, which integrate signals from various different signaling pathways important for oncogenesis. Comprehensive analysis of the EVI1 interactome has thus provided an important resource for dissecting the molecular mechanisms of EVI1-associated disease.
Ho PA, Alonzo TA, Gerbing RB, et al.High EVI1 expression is associated with MLL rearrangements and predicts decreased survival in paediatric acute myeloid leukaemia: a report from the children's oncology group.
Br J Haematol. 2013; 162(5):670-7 [PubMed
] Free Access to Full Article Related Publications
Ectopic viral integration site-1 (EVI1) is highly expressed in certain cytogenetic subsets of adult acute myeloid leukaemia (AML), and has been associated with inferior survival. We sought to examine the clinical and biological associations of EVI1(high) , defined as expression in excess of normal controls, in paediatric AML. EVI1 mRNA expression was measured via quantitative real-time polymerase chain reaction in diagnostic specimens obtained from 206 patients. Expression levels were correlated with clinical features and outcome. EVI1(high) was present in 58/206 (28%) patients. MLL rearrangements occurred in 40% of EVI1(high) patients as opposed to 12% of the EVI1(low/absent) patients (P < 0·001). No abnormalities of 3q26 were found in EVI1(high) patients by conventional cytogenetic analysis, nor were cryptic 3q26 abnormalities detected in a subset of patients screened by next-generation sequencing. French-American-British class M7 was enriched in the EVI1(high) group, accounting for 24% of these patients. EVI1(high) patients had significantly lower 5-year overall survival from study entry (51% vs. 68%, P = 0·015). However, in multivariate analysis including other established prognostic markers, EVI1 expression did not retain independent prognostic significance. EVI1 expression is currently being studied in a larger cohort of patients enrolled on subsequent Children's Oncology Group trials, to determine if EVI1(high) has prognostic value in MLL-rearranged or intermediate-risk subsets.
Dolz S, Barragán E, Fuster Ó, et al.Novel real-time polymerase chain reaction assay for simultaneous detection of recurrent fusion genes in acute myeloid leukemia.
J Mol Diagn. 2013; 15(5):678-86 [PubMed
] Related Publications
The recent World Health Organization classification recognizes different subtypes of acute myeloid leukemia (AML) according to the presence of several recurrent genetic abnormalities. Detection of these abnormalities and other molecular changes is of increasing interest because it contributes to a refined diagnosis and prognostic assessment in AML and enables monitoring of minimal residual disease. These genetic abnormalities can be detected using single RT-PCR, although the screening is still labor intensive and costly. We have developed a novel real-time RT-PCR assay to simultaneously detect 15 AML-associated rearrangements that is a simple and easily applicable method for use in clinical diagnostic laboratories. This method showed 100% specificity and sensitivity (95% confidence interval, 91% to 100% and 92% to 100%, respectively). The procedure was validated in a series of 105 patients with AML. The method confirmed all translocations detected using standard cytogenetics and fluorescence in situ hybridization and some additional undetected rearrangements. Two patients demonstrated two molecular rearrangements simultaneously, with BCR-ABL1 implicated in both, in addition to RUNX1-MECOM in one patient and PML-RARA in another. In conclusion, this novel real-time RT-PCR assay for simultaneous detection of multiple AML-associated fusion genes is a versatile and sensitive method for reliable screening of recurrent rearrangements in AML.
MicroRNAs (miRNAs), small noncoding RNAs that regulate target gene mRNAs, are known to contribute to pathogenesis of cancers. Acute myeloid leukemia (AML) is a group of heterogeneous hematopoietic malignancies with various chromosomal and/or molecular abnormalities. AML with chromosomal translocations involving the mixed lineage leukemia (MLL) gene are usually associated with poor survival. In the present study, through a large-scale, genomewide miRNA expression assay, we show that microRNA-9 (miR-9) is the most specifically up-regulated miRNA in MLL-rearranged AML compared with both normal control and non-MLL-rearranged AML. We demonstrate that miR-9 is a direct target of MLL fusion proteins and can be significantly up-regulated in expression by the latter in human and mouse hematopoietic stem/progenitor cells. Depletion of endogenous miR-9 expression by an appropriate antagomiR can significantly inhibit cell growth/viability and promote apoptosis in human MLL-rearranged AML cells, and the opposite is true when expression of miR-9 is forced. Blocking endogenous miR-9 function by anti-miRNA sponge can significantly inhibit, whereas forced expression of miR-9 can significantly promote, MLL fusion-induced immortalization/transformation of normal mouse bone marrow progenitor cells in vitro. Furthermore, forced expression of miR-9 can significantly promote MLL fusion-mediated leukemogenesis in vivo. In addition, a group of putative target genes of miR-9 exhibited a significant inverse correlation of expression with miR-9 in a series of leukemia sample sets, suggesting that they are potential targets of miR-9 in MLL-rearranged AML. Collectively, our data demonstrate that miR-9 is a critical oncomiR in MLL-rearranged AML and can serve as a potential therapeutic target to treat this dismal disease.
Singh S, Pradhan AK, Chakraborty SSUMO1 negatively regulates the transcriptional activity of EVI1 and significantly increases its co-localization with EVI1 after treatment with arsenic trioxide.
Biochim Biophys Acta. 2013; 1833(10):2357-68 [PubMed
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Aberrant expression of the proto-oncogene EVI1 (ecotropic virus integration site1) has been implicated not only in myeloid or lymphoid malignancies but also in colon, ovarian and breast cancers. Despite its importance in oncogenesis, the regulatory factors and mechanisms that potentiate the function of EVI1 and its consequences are partially known. Here we demonstrated that EVI1 is post-translationally modified by SUMO1 at lysine residues 533, 698 and 874. Although both EVI1 and SUMO1 were found to co-localize in nuclear speckles, the sumoylation mutant of EVI1 failed to co-localize with SUMO1. Sumoylation abrogated the DNA binding efficiency of EVI1 and also affected EVI1 mediated transactivation. The SUMO ligase PIASy was found to play a bi-directional role on EVI1, PIASy enhanced EVI1 sumoylation and augmented sumoylated EVI1 mediated repression. PIASy was also found to interact with EVI1 and impaired EVI1 transcriptional activity independent of its ligase activity. Arsenic trioxide (ATO) known to act as an antileukemic agent for acute promyelocytic leukemia (APL) not only enhanced EVI1 sumoylation but also enhanced the co-localization of EVI1 and SUMO1 in nuclear bodies distinct from PML nuclear bodies. ATO treatment also affected the Bcl-xL protein expression in EVI1 positive cell line. Thus, the results showed that arsenic treatment enhanced EVI1 sumoylation, deregulated Bcl-xL, which eventually may induce apoptosis in EVI1 positive cancer cells. The study for the first time explores and reports sumoylation of EVI1, which plays an essential role in regulating its function.
The development of novel technologies, such as massively parallel DNA sequencing, has led to the identification of several novel recurrent gene mutations, such as DNA methyltransferase (Dnmt)3a, ten-eleven-translocation oncogene family member 2 (TET2), isocitrate dehydrogenase (IDH)1/2, additional sex comb-like 1 (ASXL1), enhancer of zeste homolog 2 (EZH2) and ubiquitously transcribed tetratricopeptide repeat X chromosome (UTX) mutations in acute myeloid leukemia (AML) and other myeloid malignancies. These findings strongly suggest a link between recurrent genetic alterations and aberrant epigenetic regulations, resulting from an abnormal DNA methylation and histone modification status. This review focuses on the current findings of aberrant epigenetic signatures by these newly described genetic alterations. Moreover, epigenetic aberrations resulting from transcription factor aberrations, such as mixed lineage leukemia (MLL) rearrangement, ecotropic viral integration site 1 (Evi1) overexpression, chromosomal translocations and the downregulation of PU.1 are also described.
Tanaka M, Suzuki HI, Shibahara J, et al.EVI1 oncogene promotes KRAS pathway through suppression of microRNA-96 in pancreatic carcinogenesis.
Oncogene. 2014; 33(19):2454-63 [PubMed
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Despite frequent KRAS mutation, the early molecular mechanisms of pancreatic ductal adenocarcinoma (PDAC) development have not been fully elucidated. By tracking a potential regulator of another feature of PDAC precursors, acquisition of foregut or gastric epithelial gene signature, we herein report that aberrant overexpression of ecotropic viral integration site 1 (EVI1) oncoprotein, which is usually absent in normal pancreatic duct, is a widespread marker across the full spectrum of human PDAC precursors and PDAC. In pancreatic cancer cells, EVI1 depletion caused remarkable inhibition of cell growth and migration, indicating its oncogenic roles. Importantly, we found that EVI1 upregulated KRAS expression through suppression of a potent KRAS suppressor, miR-96, in pancreatic cancer cells. Collectively, the present findings suggest that EVI1 overexpression and KRAS mutation converge on activation of the KRAS pathway in early phases of pancreatic carcinogenesis and propose EVI1 and/or miR-96 as early markers and therapeutic targets in this dismal disease.
Nayak KB, Kuila N, Das Mohapatra A, et al.EVI1 targets ΔNp63 and upregulates the cyclin dependent kinase inhibitor p21 independent of p53 to delay cell cycle progression and cell proliferation in colon cancer cells.
Int J Biochem Cell Biol. 2013; 45(8):1568-76 [PubMed
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Several lines of evidence suggest that specific transcriptional events are involved in cell cycle, proliferation and differentiation processes; however, their deregulation by proto-oncogenes are involved in the development of leukemia and tumors. One such proto-oncogene is ecotropic viral integration site I which can differentially effect cell cycle progression and proliferation, in cell types of different origin. Our data for the first time shows that ecotropic viral integration site I binds to ΔNp63 promoter element directly and down regulates its expression. Down regulation of ΔNp63 induces the expression of p21 in HT-29 cells and also in colon carcinoma cells that do not express p53 including patient samples expressing low level of p53, that eventually delay cell cycle progression at G0/G1 phase. Concomitant silencing of ecotropic viral integration site I from the cells or introduction of ΔNp63 to the cells significantly rescued this phenotype, indicating the growth defect induced by ΔNp63 deficiency to be, at least in part, attributable to ecotropic viral integration site I function. The mutual regulation between ecotropic viral integration site I and ΔNp63 may constitute a novel axis which might affect the downstream pathways in cells that do not express functional p53.
Watanabe-Okochi N, Yoshimi A, Sato T, et al.The shortest isoform of C/EBPβ, liver inhibitory protein (LIP), collaborates with Evi1 to induce AML in a mouse BMT model.
Blood. 2013; 121(20):4142-55 [PubMed
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Ecotropic viral integration site 1 (Evi1) is one of the master regulators in the development of acute myeloid leukemia (AML) and myelodysplastic syndrome. High expression of Evi1 is found in 10% of patients with AML and indicates a poor outcome. Several recent studies have indicated that Evi1 requires collaborative factors to induce AML. Therefore, the search for candidate factors that collaborate with Evi1 in leukemogenesis is one of the key issues in uncovering the mechanism of Evi1-related leukemia. Previously, we succeeded in making a mouse model of Evi1-related leukemia using a bone marrow transplantation (BMT) system. In the Evi1-induced leukemic cells, we identified frequent retroviral integrations near the CCAAT/enhancer-binding protein β (C/EBPβ) gene and overexpression of its protein. These findings imply that C/EBPβ is a candidate gene that collaborates with Evi1 in leukemogenesis. Cotransduction of Evi1 and the shortest isoform of C/EBPβ, liver inhibitory protein (LIP), induced AML with short latencies in a mouse BMT model. Overexpression of LIP alone also induced AML with longer latencies. However, excision of all 3 isoforms of C/EBPβ (LAP*/LAP/LIP) did not inhibit the development of Evi1-induced leukemia. Therefore, isoform-specific intervention that targets LIP is required when we consider C/EBPβ as a therapeutic target.
Amplification of 3q26.2, found in many cancer lineages, is a frequent and early event in ovarian cancer. We previously defined the most frequent region of copy number increase at 3q26.2 to EVI1 (ecotropic viral integration site-1) and MDS1 (myelodysplastic syndrome 1) (aka MECOM), an observation recently confirmed by the cancer genome atlas (TCGA). MECOM is increased at the DNA, RNA, and protein level and likely contributes to patient outcome. Herein, we report that EVI1 is aberrantly spliced, generating multiple variants including a Del(190-515) variant (equivalent to previously reported) expressed in >90% of advanced stage serous epithelial ovarian cancers. Although EVI1(Del190-515) lacks ∼70% of exon 7, it binds CtBP1 as well as SMAD3, important mediators of TGFβ signaling, similar to wild type EVI1. This contrasts with EVI1 1-268 which failed to interact with CtBP1. Interestingly, the EVI1(Del190-515) splice variant preferentially localizes to PML nuclear bodies compared to wild type and EVI1(Del427-515). While wild type EVI1 efficiently repressed TGFβ-mediated AP-1 (activator protein-1) and plasminogen activator inhibitor-1 (PAI-1) promoters, EVI1(Del190-515) elicited a slight increase in both promoter activities. Expression of EVI1 and EVI1(Del427-515) (but not EVI1(Del190-515)) in OVCAR8 ovarian cancer cells increased cyclin E1 LMW expression and cell cycle progression. Furthermore, knockdown of specific EVI1 splice variants (both MDS1/EVI1 and EVI1(Del190-515)) markedly increased claudin-1 mRNA and protein expression in HEY ovarian and MDA-MB-231 breast cancer cells. Changes in claudin-1 were associated with alterations in specific epithelial-mesenchymal transition markers concurrent with reduced migratory potential. Collectively, EVI1 is frequently aberrantly spliced in ovarian cancer with specific forms eliciting altered functions which could potentially contribute to ovarian cancer pathophysiology.
Harada Y, Inoue D, Ding Y, et al.RUNX1/AML1 mutant collaborates with BMI1 overexpression in the development of human and murine myelodysplastic syndromes.
Blood. 2013; 121(17):3434-46 [PubMed
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RUNX1/AML1 mutations have been identified in myelodysplastic syndromes (MDSs). In a mouse bone marrow transplantation model, a RUNX1 mutant, D171N, was shown to collaborate with Evi1 in the development of MDSs; however, this is rare in humans. Using enforced expression in human CD34(+) cells, we showed that the D171N mutant, the most frequent target of mutation in the RUNX1 gene, had an increased self-renewal capacity, blocked differentiation, dysplasia in all 3 lineages, and tendency for immaturity, but no proliferation ability. BMI1 overexpression was observed in CD34(+) cells from the majority of MDS patients with RUNX1 mutations, but not in D171N-transduced human CD34(+) cells. Cotransduction of D171N and BMI1 demonstrated that BMI1 overexpression conferred proliferation ability to D171N-transduced cells in both human CD34(+) cells and a mouse bone marrow transplantation model. Stepwise transduction of D171N followed by BMI1 in human CD34(+) cells resulted in long-term proliferation with a retained CD34(+) cell fraction, which is quite similar to the phenotype in patients with higher-risk MDSs. Our results indicate that BMI1 overexpression is one of the second hit partner genes of RUNX1 mutations that contribute to the development of MDSs.
Overexpression of ecotropic viral integration site 1 (EVI1) is associated with aggressive disease in acute myeloid leukemia (AML). Despite of its clinical importance, little is known about the mechanism through which EVI1 confers resistance to antileukemic drugs. Here, we show that a human myeloid cell line constitutively overexpressing EVI1 after infection with a retroviral vector (U937_EVI1) was partially resistant to etoposide and daunorubicin as compared to empty vector infected control cells (U937_vec). Similarly, inducible expression of EVI1 in HL-60 cells decreased their sensitivity to daunorubicin. Gene expression microarray analyses of U937_EVI1 and U937_vec cells cultured in the absence or presence of etoposide showed that 77 and 419 genes were regulated by EVI1 and etoposide, respectively. Notably, mRNA levels of 26 of these genes were altered by both stimuli, indicating that EVI1 regulated genes were strongly enriched among etoposide regulated genes and vice versa. One of the genes that were induced by both EVI1 and etoposide was CDKN1A/p21/WAF, which in addition to its function as a cell cycle regulator plays an important role in conferring chemotherapy resistance in various tumor types. Indeed, overexpression of CDKN1A in U937 cells mimicked the phenotype of EVI1 overexpression, similarly conferring partial resistance to antileukemic drugs.
It has been recently shown that DNA methyl transferase overexpression is correlated with unfavourable prognosis in human malignancies while methylation deregulation remains a hallmark that defines acute myeloid leukemia (AML). The oncogenic transcription factor EVI1 is involved in methylation deregulation and its overexpression plays a major role for predicting an adverse outcome. Moreover, the identification of DNMT3A mutations in AML patients has recently been described as a poor prognostic indicator. In order to clarify relationship between these key actors in methylation mechanisms and their potential impact on patient outcomes, we analysed 195 de novo AML patients for the expression of DNMT3A, 3B (and its non-catalytic variant 3B(NC)) and their correlations with the outcome and the expression of other common prognostic genetic biomarkers (EVI1, NPM1, FLT3ITD/TKD and MLL) in adult AML. The overexpression of DNMT3B/3B(NC) is (i) significantly correlated with a shorter overall survival, and (ii) inversely significantly correlated with event-free survival and DNMT3A expression level. Moreover, multivariate analysis showed that a high expression level of DNMT3B/3B(NC) is statistically a significant independent poor prognostic indicator. This study represents the first report showing that the overexpression of DNMT3B/3B(NC) is an independent predictor of poor survival in AML. Its quantification should be implemented to the genetic profile used to stratify patients for therapeutical strategies and should be useful to identify patients who may benefit from therapy based on demethylating agents.
Rubin CM, Larson RA, Anastasi J, et al.t(3;21)(q26;q22): a recurring chromosomal abnormality in therapy-related myelodysplastic syndrome and acute myeloid leukemia.
Blood. 1990; 76(12):2594-8 [PubMed
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We have identified an identical reciprocal translocation between the long arms of chromosomes 3 and 21 with breakpoints at bands 3q26 and 21q22, [t(3;21)(q26;q22)], in the malignant cells from five adult patients with therapy-related myelodysplastic syndrome (t-MDS) or acute myeloid leukemia (t-AML). Primary diagnoses were Hodgkin's disease in two patients and ovarian carcinoma, breast cancer, and polycythemia vera in one patient each. Patients had been treated with chemotherapy including an alkylating agent for their primary disease 1 to 18 years before the development of t-MDS or t-AML. We have not observed the t(3;21) in over 1,500 patients with a myelodysplastic syndrome or acute myeloid leukemia arising de novo or in over 1,000 patients with lymphoid malignancies. We have previously reported that the t(3;21) occurs in Philadelphia chromosome-positive chronic myelogenous leukemia (CML). Thus, the t(3;21) appears to be limited to t-MDS/t-AML and CML, both of which represent malignant disorders of an early hematopoietic precursor cell. These results provide a new focus for the study of therapy-related leukemia at the molecular level.