Research IndicatorsGraph generated 06 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 06 August, 2015 using data from PubMed, MeSH and CancerIndex
Specific Cancers (4)
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
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
TICdb, Universidad de Navarra
Search the database of Translocation breakpoints In Cancer for "PRDM16"
Search the Epigenomics database and view relevant gene tracks of samples.
Latest Publications: PRDM16 (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.
Overexpression of HOXB4 in hematopoietic stem cells (HSCs) leads to increased self-renewal without causing hematopoietic malignancies in transplanted mice. The molecular basis of HOXB4-mediated benign HSC expansion in vivo is not well understood. To gain further insight into the molecular events underlying HOXB4-mediated HSC expansion, we analyzed gene expression changes at multiple time points in Lin(-)Sca1(+)c-kit(+) cells from mice transplanted with bone marrow cells transduced with a MSCV-HOXB4-ires-YFP vector. A distinct HOXB4 transcriptional program was reproducibly induced and stabilized by 12 weeks after transplant. Dynamic expression changes were observed in genes critical for HSC self-renewal as well as in genes involved in myeloid and B-cell differentiation. Prdm16, a transcription factor associated with human acute myeloid leukemia, was markedly repressed by HOXB4 but upregulated by HOXA9 and HOXA10, suggesting that Prdm16 downregulation was involved in preventing leukemia in HOXB4 transplanted mice. Functional evidence to support this mechanism was obtained by enforcing coexpression of sPrdm16 and HOXB4, which led to enhanced self-renewal, myeloid expansion, and leukemia. Altogether, these studies define the transcriptional pathways involved in HOXB4 HSC expansion in vivo and identify repression of Prdm16 transcription as a mechanism by which expanding HSCs avoid leukemic transformation.
AIMS: To investigate the changes of expression and methylation status of PRDM2, PRDM5, PRDM16 in lung cancer cells after treatment with demethylation agent.
METHODS: A549 (lung adenocarcinoma cell line), HTB-182 (lung squamous cell carcinoma cell line) and HBE (normal bronchial cell line) were treated with 5-aza-2dC. The methylation state of PRDM2, PRDM5, PRDM16 was detected by MSP. The expression of PRDM2, PRDM5, PRDM16 was detected by RT-PCR and Western blot analysis. Cell growth was detected by MTT assay.
RESULTS: 5-aza-2-dC reduced the methylation of PRDM2, PRDM5, PRDM16 gene in A549 and HTB-182 cells but not in HBE cells. Consistently, 5-aza-2dC increased mRNA and protein expression of PRDM2, PRDM5, PRDM16 in A549 and HTB-182 cells but not in HBE cells. Furthermore, 5-aza-2dC inhibited the growth of A549 and HTB-182 cells but not HBE cells.
CONCLUSIONS: PRDM2, PRDM5, PRDM16 promoters are methylated and their expression is suppressed in lung cancer cells. Demethylation drug 5-aza-2dC could upregulate the expression of PRDM2, PRDM5, PRDM16 and suppress lung cancer cell growth. 5-aza-2dC has potential to be used for lung cancer therapy by epigenetic mechanism.
Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Chromosomal instability (CIN) is a major driving force of microsatellite stable (MSS) sporadic CRC. CIN tumours are characterised by a large number of somatic chromosomal copy number aberrations (SCNA) that frequently affect oncogenes and tumour suppressor genes. The main aim of this work was to identify novel candidate CRC driver genes affected by recurrent and focal SCNA. High resolution genome-wide comparative genome hybridisation (CGH) arrays were used to compare tumour and normal DNA for 53 sporadic CRC cases. Context corrected common aberration (COCA) analysis and custom algorithms identified 64 deletions and 32 gains of focal minimal common regions (FMCR) at high frequency (>10%). Comparison of these FMCR with published genomic profiles from CRC revealed common overlap (42.2% of deletions and 34.4% of copy gains). Pathway analysis showed that apoptosis and p53 signalling pathways were commonly affected by deleted FMCR, and MAPK and potassium channel pathways by gains of FMCR. Candidate tumour suppressor genes in deleted FMCR included RASSF3, IFNAR1, IFNAR2 and NFKBIA and candidate oncogenes in gained FMCR included PRDM16, TNS1, RPA3 and KCNMA1. In conclusion, this study confirms some previously identified aberrations in MSS CRC and provides in silico evidence for some novel candidate driver genes.
Zhou Z, Darwal MA, Cheng EA, et al.Cellular reprogramming into a brown adipose tissue-like phenotype by co-expression of HB-EGF and ADAM 12S.
Growth Factors. 2013; 31(6):185-98 [PubMed
] Related Publications
Abnormal adipogenesis leads to excessive fat accumulation and several health disorders. Mouse fibroblasts (MLC) transfected with ADAM 12S and HB-EGF promoted lipid accumulation. Addition of KBR-7785, an ADAM 12S inhibitor, to HB-EGF/ADAM 12S expressing cells suppressed adipogenesis. BrdU incorporation was attenuated and enhanced mitotracker staining was observed in HB-EGF/ADAM 12S cells. Quantitative real time RT-PCR resulted in elevated levels of expression of three brown adipose tissue (BAT) genes (PRDM16, PGC-1α, and UCP-1), while expression levels of the three white adipose tissue (WAT) genes (PPARγ, C/EBPα, and AKT-1) were unaltered in HB-EGF/ADAM 12S cells. Amino- or carboxy-terminal deletions of HB-EGF (HB-EGFΔN and HB-EGFΔC) co-expressed with ADAM 12S stimulated lipid accumulation. Human epidermoid carcinoma cells (A431) also exhibited lipid accumulation by HB-EGF/ADAM 12S co-expression. These studies suggest ADAM 12S and HB-EGF are involved in cellular plasticity resulting in the production of BAT-like cells and offers insight into novel therapeutic approaches for fighting obesity.
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
] Related Publications
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.
Frontini A, Vitali A, Perugini J, et al.White-to-brown transdifferentiation of omental adipocytes in patients affected by pheochromocytoma.
Biochim Biophys Acta. 2013; 1831(5):950-9 [PubMed
] Related Publications
In all mammals, white adipose tissue (WAT) and brown adipose tissue (BAT) are found together in several fat depots, forming a multi-depot organ. Adrenergic stimulation induces an increase in BAT usually referred to as "browning". This phenomenon is important because of its potential use in curbing obesity and related disorders; thus, understanding its cellular mechanisms in humans may be useful for the development of new therapeutic strategies. Data in rodents have supported the direct transformation of white into brown adipocytes. Biopsies of pure white omental fat were collected from 12 patients affected by the catecholamine-secreting tumor pheochromocytoma (pheo-patients) and compared with biopsies from controls. Half of the omental fat samples from pheo-patients contained uncoupling protein 1 (UCP1)-immunoreactive-(ir) multilocular cells that were often arranged in a BAT-like pattern endowed with noradrenergic fibers and dense capillary network. Many UCP1-ir adipocytes showed the characteristic morphology of paucilocular cells, which we have been described as cytological marker of transdifferentiation. Electron microscopy showed increased mitochondrial density in multi- and paucilocular cells and disclosed the presence of perivascular brown adipocyte precursors. Brown fat genes, such as UCP1, PR domain containing 16 (PRDM16) and β3-adrenoreceptor, were highly expressed in the omentum of pheo-patients and in those cases without visible morphologic re-arrangement. Of note, the brown determinant PRDM16 was detected by immunohistochemistry only in nuclei of multi- and paucilocular adipocytes. Quantitative electron microscopy and immunohistochemistry for Ki67 suggest an unlikely contribution of proliferative events to the phenomenon. The data support the idea that, in adult humans, white adipocytes of pure white fat that are subjected to adrenergic stimulation are able to undergo a process of direct transformation into brown adipocytes. This article is part of a Special Issue entitled Brown and White Fat: From Signaling to Disease.
Chen J, Chen Y, Chen ZMiR-125a/b regulates the activation of cancer stem cells in paclitaxel-resistant colon cancer.
Cancer Invest. 2013; 31(1):17-23 [PubMed
] Related Publications
In this study, we investigated ALDH1A3, Mcl1, and miR-125a/b expression in HT29 cells and the effect of miR-125a/b on ALDH1A3 and Mcl1 expression. Our results showed that low expression of miR-125a/b and high expression of ALDH1A3 and Mel1 were observed in both ALDH1-positive HT29 and HT29-taxol cells. Overexpression of miR-125a/b significantly inhibited ALDH1A3 and Mcl1 expression, reduced cell survival, and increased cell apoptosis in HT29-taxol cells. Injection of miR-125a/b expression vector inhibited tumor growth in xenograft HT29-taxol mouse model. The current study suggested that miR-125a/b expression plays a key role in chemoresistance through upregulating ALDH1A3 and Mcl1 gene expression.
An 87-yr-old woman was diagnosed with AML with myelodysplasia-related changes (AML-MRC). The initial complete blood count showed Hb level of 5.9 g/dL, platelet counts of 27 × 10(9)/L, and white blood cell counts of 85.33 × 10(9)/L with 55% blasts. Peripheral blood samples were used in all the tests, as bone marrow examination could not be performed because of the patient's extremely advanced age and poor general health condition. Flow cytometric analysis, chromosome analysis, FISH, and reverse transcriptase-PCR (RT-PCR) results indicated AML-MRC resulting from t(3;21) with the RUNX1-MECOM fusion gene. To our knowledge, this is the second most elderly de novo AML patient associated with t(3;21) to be reported.
Wolf S, Rudolph C, Morgan M, et al.Selection for Evi1 activation in myelomonocytic leukemia induced by hyperactive signaling through wild-type NRas.
Oncogene. 2013; 32(25):3028-38 [PubMed
] Related Publications
Activation of NRas signaling is frequently found in human myeloid leukemia and can be induced by activating mutations as well as by mutations in receptors or signaling molecules upstream of NRas. To study NRas-induced leukemogenesis, we retrovirally overexpressed wild-type NRas in a murine bone marrow transplantation (BMT) model in C57BL/6J mice. Overexpression of wild-type NRas caused myelomonocytic leukemias ∼3 months after BMT in the majority of mice. A subset of mice (30%) developed malignant histiocytosis similar to mice that received mutationally activated NRas(G12D)-expressing bone marrow. Aberrant Ras signaling was demonstrated in cells expressing mutationally active or wild-type NRas, as increased activation of Erk and Akt was observed in both models. However, more NRas(G12D) were found to be in the activated, GTP-bound state in comparison with wild-type NRas. Consistent with observations reported for primary human myelomonocytic leukemia cells, Stat5 activation was also detected in murine leukemic cells. Furthermore, clonal evolution was detected in NRas wild-type-induced leukemias, including expansion of clones containing activating vector insertions in known oncogenes, such as Evi1 and Prdm16. In vitro cooperation of NRas and Evi1 improved long-term expansion of primary murine bone marrow cells. Evi1-positive cells upregulated Bcl-2 and may, therefore, provide anti-apoptotic signals that collaborate with the NRas-induced proliferative effects. As activation of Evi1 has been shown to coincide with NRAS mutations in human acute myeloid leukemia, our murine model recapitulates crucial events in human leukemogenesis.
Chemotherapy with alkylating agents for treating malignant disease results in myelosuppression that can significantly limit dose escalation and potential clinical efficacy. Gene therapy using mutant methylguanine methyltransferase (P140K) gene-modified hematopoietic stem and progenitor cells may circumvent this problem by abrogating the toxic effects of chemotherapy on hematopoietic cells. However, this approach has not been evaluated clinically. Here, we show efficient polyclonal engraftment of autologous P140K-modified hematopoietic stem and progenitor cells in three patients with glioblastoma. Increases in P140K-modified cells after transplant indicate selection of gene-modified hematopoietic repopulating cells. Longitudinal retroviral integration site (RIS) analysis identified more than 12,000 unique RISs in the three glioblastoma patients, with multiple clones present in the peripheral blood of each patient throughout multiple chemotherapy cycles. To assess safety, we monitored RIS distribution over the course of chemotherapy treatments. Two patients exhibited emergence of prominent clones harboring RISs associated with the intronic coding region of PRDM16 (PR domain-containing 16) or the 3' untranslated region of HMGA2 (high-mobility group A2) genes with no adverse clinical outcomes. All three patients surpassed the median survival for glioblastoma patients with poor prognosis, with one patient alive and progression-free more than 2 years after diagnosis. Thus, transplanted P140K-expressing hematopoietic stem and progenitor cells are chemoprotective, potentially maximizing the drug dose that can be administered.
The determinants of normal and leukemic stem cell self-renewal remain poorly characterized. We report that expression of the reactive oxygen species (ROS) scavenger glutathione peroxidase 3 (GPx3) positively correlates with the frequency of leukemia stem cells (LSCs) in Hoxa9+Meis1-induced leukemias. Compared with a leukemia with a low frequency of LSCs, a leukemia with a high frequency of LSCs showed hypomethylation of the Gpx3 promoter region, and expressed high levels of Gpx3 and low levels of ROS. LSCs and normal hematopoietic stem cells (HSCs) engineered to express Gpx3 short hairpin RNA (shRNA) were much less competitive in vivo than control cells. However, progenitor cell proliferation and differentiation was not affected by Gpx3 shRNA. Consistent with this, HSCs overexpressing Gpx3 were significantly more competitive than control cells in long-term repopulation experiments, and overexpression of the self-renewal genes Prdm16 or Hoxb4 boosted Gpx3 expression. In human primary acute myeloid leukemia samples, GPX3 expression level directly correlated with adverse prognostic outcome, revealing a potential novel target for the eradication of LSCs.
Duhoux FP, Ameye G, Montano-Almendras CP, et al.PRDM16 (1p36) translocations define a distinct entity of myeloid malignancies with poor prognosis but may also occur in lymphoid malignancies.
Br J Haematol. 2012; 156(1):76-88 [PubMed
] Related Publications
The PRDM16 (1p36) gene is rearranged in acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) with t(1;3)(p36;q21), sharing characteristics with AML and MDS with MECOM (3q26.2) translocations. We used fluorescence in situ hybridization to study 39 haematological malignancies with translocations involving PRDM16 to assess the precise breakpoint on 1p36 and the identity of the partner locus. Reverse-transcription polymerase chain reaction (PCR) was performed in selected cases in order to confirm the partner locus. PRDM16 expression studies were performed on bone marrow samples of patients, normal controls and CD34(+) cells using TaqMan real-time quantitative PCR. PRDM16 was rearranged with the RPN1 (3q21) locus in 30 cases and with other loci in nine cases. The diagnosis was AML or MDS in most cases, except for two cases of lymphoid proliferation. We identified novel translocation partners of PRDM16, including the transcription factors ETV6 and IKZF1. Translocations involving PRDM16 lead to its overexpression irrespective of the consequence of the rearrangement (fusion gene or promoter swap). Survival data suggest that patients with AML/MDS and PRDM16 translocations have a poor prognosis despite a simple karyotype and a median age of 65 years. There seems to be an over-representation of late-onset therapy-related myeloid malignancies.
Fluorescence in situ hybridization was performed to characterize 81 cases of myeloid and lymphoid malignancies with cytogenetic 1p36 alterations not affecting the PRDM16 locus. In total, three subgroups were identified: balanced translocations (N = 27) and telomeric rearrangements (N = 15), both mainly observed in myeloid disorders; and unbalanced non-telomeric rearrangements (N = 39), mainly observed in lymphoid proliferations and frequently associated with a highly complex karyotype. The 1p36 rearrangement was isolated in 12 cases, mainly myeloid disorders. The breakpoints on 1p36 were more widely distributed than previously reported, but with identifiable rare breakpoint cluster regions, such as the TP73 locus. We also found novel partner loci on 1p36 for the known multi-partner genes HMGA2 and RUNX1. We precised the common terminal 1p36 deletion, which has been suggested to have an adverse prognosis, in B-cell lymphomas [follicular lymphomas and diffuse large B-cell lymphomas with t(14;18)(q32;q21) as well as follicular lymphomas without t(14;18)]. Intrachromosomal telomeric repetitive sequences were detected in at least half the cases of telomeric rearrangements. It is unclear how the latter rearrangements occurred and whether they represent oncogenic events or result from chromosomal instability during oncogenesis.
Lee P, Zhao JT, Swarbrick MM, et al.High prevalence of brown adipose tissue in adult humans.
J Clin Endocrinol Metab. 2011; 96(8):2450-5 [PubMed
] Related Publications
CONTEXT: Positron emission tomography (PET)-computed tomography (CT) has identified metabolically active supraclavicular fat in adult humans based on uptake of labeled glucose and confirmed to be brown adipose tissue (BAT) histologically. However, PET-CT has estimated a prevalence of BAT as low as 5% in adult humans, casting doubt on its significance. The true prevalence of BAT is unknown because of the suboptimal sensitivity of standard PET-CT.
OBJECTIVE: The objective of the study was to determine whether BAT is present in PET-negative supraclavicular fat.
DESIGN: This was a prospective cohort study.
SETTING: The study was conducted at a tertiary referral hospital.
PATIENTS: Seventeen patients who underwent preoperative PET-CT for staging of head and neck malignancy participated in the study.
MAIN OUTCOME: The main outcome was signature BAT gene transcripts and protein in biopsies of supraclavicular fat with sc fat as negative control.
RESULTS: PET-CT was positive in three and negative in 14 patients. PET-positive fat harbored multilobulated lipid droplets and stained strongly for uncoupling protein 1 (UCP1). These features are absent in sc fat. By contrast, PET-negative fat contained a predominance of cells with unilobulated lipid droplets, with scattered cells containing multilobulated lipid droplets and variable UCP1 staining. Molecular analyses of fat biopsies showed lower but clear expression of UCP1, NDUFS3 (NADH dehydrogenase (ubiquinone) iron-sulfur protein 3), β₃-adrenoceptor, and PRDM16 (PR domain containing 16) transcripts.
CONCLUSIONS: BAT is present in supraclavicular fat, regardless of PET status. BAT is highly prevalent in adult humans, and its abundance determines PET status.
Quentin S, Cuccuini W, Ceccaldi R, et al.Myelodysplasia and leukemia of Fanconi anemia are associated with a specific pattern of genomic abnormalities that includes cryptic RUNX1/AML1 lesions.
Blood. 2011; 117(15):e161-70 [PubMed
] Related Publications
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.
Mitsuhashi J, Hosoyama H, Tsukahara S, et al.In vivo expansion of MDR1-transduced cells accompanied by a post-transplantation chemotherapy regimen with mitomycin C and methotrexate.
J Gene Med. 2010; 12(7):596-603 [PubMed
] Related Publications
BACKGROUND: A recurrent breast cancer patient received high-dose chemotherapy, a transplant of multidrug resistance 1 (MDR1)-transduced cells and four different protocols of post-transplantation chemotherapy. We report the analysis of MDR1-transduced cells in this patient.
METHODS: MDR1 transgene levels in the peripheral blood mononuclear cells of the patient were evaluated by polymerase chain reaction (PCR). Retroviral integration sites of the MDR1-transduced cells were identified by linear amplification-mediated (LAM)-PCR.
RESULTS: Twelve days after transplantation, approximately 1% of the peripheral blood mononuclear cells were MDR1 transgene-positive. The transgene levels decreased quickly, and were at low levels until day 504. A remarkable increase in MDR1 transgene-positive cells was observed on day 532, during combination chemotherapy with mitomycin C and methotrexate. Using LAM-PCR, 31 MDR1-transduced clones were identified, and eight of these were long-life clones that survived for more than 500 days. Among the 31 clones, ten had a retroviral integration site near genes listed in the Retroviral Tagged Cancer Gene (RTCG) Database. Two long-life clones, N-30 and N-31, had retroviral integration sites within the MDS1-EVI1 locus. Another two long-life clones had integration sites close to PRDM16 or CUEDC1.
CONCLUSIONS: These results suggest that MDR1-transduced cells were enriched in vivo by an MDR1 substrate, mitomycin C. The possible activation of EVI1 or other RTCGs by retroviral insertion may have affected the survival and persistence of a proportion of the transduced cells.
Leiomyosarcoma (LMS) is a soft tissue tumor with a significant degree of morphologic and molecular heterogeneity. We used integrative molecular profiling to discover and characterize molecular subtypes of LMS. Gene expression profiling was performed on 51 LMS samples. Unsupervised clustering showed three reproducible LMS clusters. Array comparative genomic hybridization (aCGH) was performed on 20 LMS samples and showed that the molecular subtypes defined by gene expression showed distinct genomic changes. Tumors from the 'muscle-enriched' cluster showed significantly increased copy number changes (P=0.04). A majority of the muscle-enriched cases showed loss at 16q24, which contains Fanconi anemia, complementation group A, known to have an important role in DNA repair, and loss at 1p36, which contains PRDM16, of which loss promotes muscle differentiation. Immunohistochemistry (IHC) was performed on LMS tissue microarrays (n=377) for five markers with high levels of messenger RNA in the muscle-enriched cluster (ACTG2, CASQ2, SLMAP, CFL2 and MYLK) and showed significantly correlated expression of the five proteins (all pairwise P<0.005). Expression of the five markers was associated with improved disease-specific survival in a multivariate Cox regression analysis (P<0.04). In this analysis that combined gene expression profiling, aCGH and IHC, we characterized distinct molecular LMS subtypes, provided insight into their pathogenesis, and identified prognostic biomarkers.
Translocations resulting in ectopic expression of the TLX1 homeobox gene (previously known as HOX11) are recurrent events in human T-cell acute lymphoblastic leukemia (T-ALL). Transduction of primary murine hematopoietic stem/progenitor cells with retroviral vectors expressing TLX1 readily yields immortalized hematopoietic progenitor cell lines. Understanding the processes involved in TLX1-mediated cellular immortalization should yield insights into the growth and differentiation pathways altered by TLX1 during the development of T-ALL. In recent clinical gene therapy trials, hematopoietic clonal dominance or T-ALL-like diseases have occurred as a direct consequence of insertional activation of the EVI1, PRDM16 or LMO2 proto-oncogenes by the retroviral vectors used to deliver the therapeutic genes. Additionally, the generation of murine hematopoietic progenitor cell lines due to retroviral integrations into Evi1 or Prdm16 has also been recently reported. Here, we determined by linker-mediated nested polymerase chain reaction the integration sites in eight TLX1-immortalized hematopoietic cell lines. Notably, no common integration site was observed among the cell lines. Moreover, no insertions into the Evi1 or Prdm16 genes were identified although insertion near Lmo2 was observed in one instance. However, neither Lmo2 nor any of the other genes examined surrounding the integration sites showed differential vector-influenced expression compared to the cell lines lacking such insertions. While we cannot exclude the possibility that insertional side effects transiently provided a selective growth/survival advantage to the hematopoietic progenitor populations, our results unequivocally rule out insertions into Evi1 and Prdm16 as being integral to the TLX1-initiated immortalization process.
Takahata M, Inoue Y, Tsuda H, et al.SKI and MEL1 cooperate to inhibit transforming growth factor-beta signal in gastric cancer cells.
J Biol Chem. 2009; 284(5):3334-44 [PubMed
] Related Publications
Chromosomal amplification occurs frequently in solid tumors and is associated with poor prognosis. Several reports demonstrated the cooperative effects of oncogenic factors in the same amplicon during cancer development. However, the functional correlation between the factors remains unclear. Transforming growth factor (TGF)-beta signaling plays important roles in cytostasis and normal epithelium differentiation, and alterations in TGF-beta signaling have been identified in many malignancies. Here, we demonstrated that transcriptional co-repressors of TGF-beta signaling, SKI and MDS1/EVI1-like gene 1 (MEL1), were aberrantly expressed in MKN28 gastric cancer cells by chromosomal co-amplification of 1p36.32. SKI and MEL1 knockdown synergistically restored TGF-beta responsiveness in MKN28 cells and reduced tumor growth in vivo. MEL1 interacted with SKI and inhibited TGF-beta signaling by stabilizing the inactive Smad3-SKI complex on the promoter of TGF-beta target genes. These findings reveal a novel mechanism where distinct transcriptional co-repressors are co-amplified and functionally interact, and provide molecular targets for gastric cancer treatment.
Deluche L, Joha S, Corm S, et al.Cryptic and partial deletions of PRDM16 and RUNX1 without t(1;21)(p36;q22) and/or RUNX1-PRDM16 fusion in a case of progressive chronic myeloid leukemia: a complex chromosomal rearrangement of underestimated frequency in disease progression?
Genes Chromosomes Cancer. 2008; 47(12):1110-7 [PubMed
] Related Publications
Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by the presence in leukemic stem cells of the Philadelphia chromosome (Ph) and the formation of the BCR-ABL1 fusion. Untreated, the disease progresses to accelerate phase and blast crisis in which hematopoietic differentiation has become arrested. CML progression is frequently associated with cytogenetic evidence of clonal evolution, defined as additional chromosomal aberrations. We here report a CML resistant to tyrosine kinase inhibitors that rapidly progressed to blastic phase. At this time, array CGH performed on CD34(+) cells revealed cryptic partial deletions of both PRDM16 and RUNX1 and duplication of the der(21) chromosome. These genomic rearrangements were confirmed by FISH with probes targeting the deletion on chromosome 21 (24 kb), and with BAC probes flanking the deletion on 1p36 (220 kb). However, no cryptic t(1;21)(p36;q22) and/or RUNX1-PRDM16 were detected, suggesting that these deletions are the residual hallmarks of a more complex mechanism of chromosomal rearrangement, as indicated by the additional inversion of the region bounded by 1p36.32 and 1p36.12 breaks. At the molecular level, these abnormalities lead to the overexpression of the PR-domain negative oncogenic isoform of PRDM16, associated with two deleted copies within the runt domain of C-teminal aberrant RUNX1. These events are not detectable by conventional cytogenetic and molecular strategies, and may be of underestimated frequency in disease progression.
Roche-Lestienne C, Deluche L, Corm S, et al.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.
Blood. 2008; 111(7):3735-41 [PubMed
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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.
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.
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.
Retroviruses can induce hematopoietic disease via insertional mutagenesis of cancer genes and provide valuable molecular tags for cancer gene discovery. Here we show that insertional mutagenesis can also identify genes that promote the immortalization of hematopoietic cells, which normally have only limited self-renewal. Transduction of mouse bone marrow cells with replication-incompetent murine stem cell virus (MSCV) expressing only neo, followed by serial passage in liquid culture containing stem cell factor (SCF) and interleukin-3 (IL-3), produced immortalized immature myeloid cell lines with neutrophil and macrophage differentiation potential in about 50% of the infected cultures. More than half of the lines have MSCV insertions at Evi1 or Prdm16. These loci encode transcription factor homologs and are validated human myeloid leukemia genes. Integrations are located in intron 1 or 2, where they promote expression of truncated proteins lacking the PRDI-BF1-RIZ1 homologous (PR) domain, similar to what is observed in human leukemias with EVI1 or PRDM16 mutations. Evi1 overexpression alone appears sufficient to immortalize immature myeloid cells and does not seem to require any other cooperating mutations. Genes identified by insertional mutagenesis by their nature could also be involved in immortalization of leukemic stem cells, and thus represent attractive drug targets for treating cancer.
Sakai I, Tamura T, Narumi H, et al.Novel RUNX1-PRDM16 fusion transcripts in a patient with acute myeloid leukemia showing t(1;21)(p36;q22).
Genes Chromosomes Cancer. 2005; 44(3):265-70 [PubMed
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The t(1;21)(p36;q22) is a recurrent chromosome abnormality associated with therapy-related acute myeloid leukemia (AML). Although involvement of RUNX1 has been detected by fluorescence in situ hybridization analysis, the partner gene has not been reported previously. We identified a novel RUNX1 partner gene, MDS1/EVI1-like-gene 1 (PRDM16), in an AML patient with t(1;21). Alternative splicing of the fusion gene generates five different fusion transcripts. In two of them, the PRDM16 reading frame is maintained in the fusion with RUNX1, suggesting that the RUNX1-PRDM16 gene fusion results in the production of a protein that is highly homologous to the RUNX1-MDS1/EVI1 chimeric protein. It is suggested that PRDM16 and MDS1/EVI1 share a common molecular mechanism for the leukemogenesis of RUNX1-associated leukemia. Characterization of the RUNX1-PRDM16 fusion protein and comparison with the RUNX1-MDS1/EVI1 protein will facilitate the understanding of the mechanisms underlying RUNX1-associated leukemia.
BACKGROUND: Osteosarcoma is a highly malignant bone neoplasm of children and young adults. It is characterized by extremely complex karyotypes and high frequency of chromosomal amplifications. Currently, only the histological response (degree of necrosis) to therapy represent gold standard for predicting the outcome in a patient with non-metastatic osteosarcoma at the time of definitive surgery. Patients with lower degree of necrosis have a higher risk of relapse and poor outcome even after chemotherapy and complete resection of the primary tumor. Therefore, a better understanding of the underlying molecular genetic events leading to tumor initiation and progression could result in the identification of potential diagnostic and therapeutic targets.
METHODS: We used a genome-wide screening method - array based comparative genomic hybridization (array-CGH) to identify DNA copy number changes in 48 patients with osteosarcoma. We applied fluorescence in situ hybridization (FISH) to validate some of amplified clones in this study.
RESULTS: Clones showing gains (79%) were more frequent than losses (66%). High-level amplifications and homozygous deletions constitute 28.6% and 3.8% of tumor genome respectively. High-level amplifications were present in 238 clones, of which about 37% of them showed recurrent amplification. Most frequently amplified clones were mapped to 1p36.32 (PRDM16), 6p21.1 (CDC5L, HSPCB, NFKBIE), 8q24, 12q14.3 (IFNG), 16p13 (MGRN1), and 17p11.2 (PMP22 MYCD, SOX1,ELAC27). We validated some of the amplified clones by FISH from 6p12-p21, 8q23-q24, and 17p11.2 amplicons. Homozygous deletions were noted for 32 clones and only 7 clones showed in more than one case. These 7 clones were mapped to 1q25.1 (4 cases), 3p14.1 (4 cases), 13q12.2 (2 cases), 4p15.1 (2 cases), 6q12 (2 cases), 6q12 (2 cases) and 6q16.3 (2 cases).
CONCLUSIONS: This study clearly demonstrates the utility of array CGH in defining high-resolution DNA copy number changes and refining amplifications. The resolution of array CGH technology combined with human genome database suggested the possible target genes present in the gained or lost clones.
Hosoya N, Ogawa S, Motokura T, et al.Molecular cytogenetic analyses of HIG, a novel human cell line carrying t(1;3)(p36.3;q25.3) established from a patient with chronic myelogenous leukemia in blastic crisis.
Int J Hematol. 2003; 78(5):432-8 [PubMed
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Chromosomal abnormalities involving 1p36, 3q21, and/or 3q26 have been reported in a subset of myeloid neoplasms having characteristic dysmegakaryopoiesis, and the overexpression of EVI1 on 3q26 or of MEL1 on 1p36 has been implicated in their pathogenesis. We describe molecular cytogenetic analyses of a novel human cell line, HIG, established from a unique case in which a novel translocation t(1;3)(p36;q26) appeared as the sole additional chromosomal abnormality at the time of blastic transformation of chronic myelogenous leukemia. The patient displayed clinical features resembling those of the 3q21q26 syndrome. The HIG cell line retained der(1)t(1;3)(p36;q26) but lost t(9;22)(q34;q11). To identify the relevant gene that would be deregulated by this translocation, we molecularly cloned the translocation's breakpoints. They were distant from the breakpoint cluster regions of the 3q21q26 syndrome or t(1;3)(p36;q21), and neither the EVI1 nor the MEL1 transcript was detected in the HIG cell line. None of the genes located within 150 kilobase pairs of the breakpoints were aberrantly expressed, suggesting that in this case other gene(s) more distant from the breakpoints are deregulated by possible remote effects. Further analyses of the deregulated genes in the HIG cell line should provide important insight into the mechanisms involved in these types of leukemias.
Yoshida M, Nosaka K, Yasunaga J, et al.Aberrant expression of the MEL1S gene identified in association with hypomethylation in adult T-cell leukemia cells.
Blood. 2004; 103(7):2753-60 [PubMed
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DNA methylation plays critical roles in the development and differentiation of mammalian cells, and its dysregulation has been implicated in oncogenesis. This study was designed to determine whether DNA hypomethylation-associated aberrant gene expression is involved in adult T-cell leukemia (ATL) leukemogenesis. We isolated hypomethylated DNA regions of ATL cells compared with peripheral blood mononuclear cells from a carrier by a methylated CpG-island amplification/representational difference analysis method. The DNA regions identified contained MEL1, CACNA1H, and Nogo receptor genes. Sequencing using sodium bisulfite-treated genomic DNAs revealed the decreased methylated CpG sites, confirming that this method detected hypomethylated DNA regions. Moreover, these hypomethylated genes were aberrantly transcribed. Among them, MEL1S, an alternatively spliced form of MEL1 lacking the PR (positive regulatory domain I binding factor 1 and retinoblastoma-interacting zinc finger protein) domain, was frequently transcribed in ATL cells, and the transcriptional initiation sites were identified upstream from exons 4 and 6. Transfection of MEL1S into CTLL-2 cells conferred resistance against transforming growth factor beta (TGF-beta), suggesting that aberrant expression of MEL1S was associated with dysregulation of TGF-beta-mediated signaling. Although Tax renders cells resistant to TGF-beta, Tax could not be produced in most fresh ATL cells, in which MEL1S might be responsible for TGF-beta resistance. Our results suggest that aberrant gene expression associated with DNA hypomethylation is implicated in leukemogenesis of ATL.
Barjesteh van Waalwijk van Doorn-Khosrovani S, Erpelinck C, Löwenberg B, Delwel RLow expression of MDS1-EVI1-like-1 (MEL1) and EVI1-like-1 (EL1) genes in favorable-risk acute myeloid leukemia.
Exp Hematol. 2003; 31(11):1066-72 [PubMed
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OBJECTIVE: The expression of an MDS1-EVI1-like-1 (MEL1) gene is reported in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) with translocation t(1;3)(p36;q21). MEL1 (at chromosome band 1p36.3) is thought to be transcriptionally activated as a result of juxtaposition to the RPN1 gene at 3q21. It is not known whether MEL1 expression is restricted to cases with this particular translocation.
MATERIALS AND METHODS: Using real-time polymerase chain reaction, we measured MEL1 expression levels, normal bone marrow, and distinct blood cell fractions in 162 de novo AML patients. We also investigated the existence of an EVI1-like gene (EL1) by applying the same method. The existence of these transcripts was confirmed by Northern blot analysis.
RESULTS: MEL1 expression was detected in 87% (141/162) of de novo AML patients. The EL1 transcript also was detected in the majority of the patients. EL1 expression levels highly correlated with MEL1 expression levels in AML cases. Variable MEL1/EL1 expression levels were observed. However, all the patients with favorable-risk karyotypes, i.e., with t(15;17), t(8;21), or inv(16), showed low MEL1/EL1 expression levels. Expression analysis of MEL1/EL1 compared with MDS1-EVI1/EVI1 in distinct normal marrow or blood cell fractions revealed that 1) all four gene products are expressed in CD34(+) progenitor cell fractions; 2) both MEL1 and EVI1 are turned down in neutrophils and monocytes/macrophages; while 3) MDS1-EVI1 and EL1 remain expressed in mature blood cell fractions.
CONCLUSION: Our data suggest that simultaneous low MEL1/EL1 expression in AML is abnormal and that favorable disease is highly associated with this abnormal phenotype.