IKZF1 deletions Are Detected In 40.3% Of 270 Adult B-Precursor-ALL and Are Independently Associated With BCR-ABL1 Positivity and Inferior Outcome

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1372-1372
Author(s):  
Annette Fasan ◽  
Claudia Haferlach ◽  
Madlen Ulke ◽  
Wolfgang Kern ◽  
Torsten Haferlach ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Normal Karyotype ◽  
Chromosome 7 ◽  
Employment Equity ◽  
Gene Deletions ◽  
Exon 2 ◽  
Monosomy 7 ◽  
Significant Difference ◽  
Equity Ownership ◽  
Exon 4

Abstract Introduction Total or intragenic deletions of or within the IKZF1 (Ikaros) gene on chromosome 7 have been shown to be frequent in B-precursor-ALL (B-ALL), highly associated with BCR-ABL1 positive (BCR-ABL1pos) B-ALL (Mullighan et al., Nature 2008), but also present in BCR-ABL1 negative (BCR-ABL1neg) B-ALL (Mullighan et al., N Engl J Med 2009). IKZF1 deletion pattern is known to be heterogenous and deletions involving exon 4, 7 or 8 are likely to have the same impact as whole gene deletions. To analyse intragenic IKZF1 deletions, we used a multiplex-PCR approach, which represents the standard detection method. In addition, we used multiplex ligation-dependent probe amplification (MLPA), which allows the detection of whole IKZF1 deletions. Aim We aimed at characterization of IKZF1 deletions pattern and correlation to clinical features in a cohort of 270 adult B-ALL cases. Patients and Methods IKZF1 deletion status was analyzed in blood or bone marrow samples from 270 adult B-ALL cases (subtypes as diagnosed by immunophenotyping: c-ALL: n=197; Pro-B ALL: n=51; Pre-B ALL: n=5). Additionally, 17 mature B-ALL cases were analyzed. The cohort consisted of 137 females and 133 males, median age was 58.3 years (range: 18.1-91.4 years). The cohort was classified into seven subgroups according to the following cytogenetics: 1) t(9;22)(q34;q11) (n=97), 2) 11q23/MLL rearrangements (n=24), 3) MYC rearrangements (n=14), 4) hypodiploidy (n=21), 5) hyperdiploidy (n=32), 6) normal karyotype (n=38), 7) other cytogenetic aberrations (n=42). In one case no cytogenetic data was available. In all 270 cases intragenic IKZF1 deletions were investigated by breakpoint-specific fluorescent multiplex PCR (according to Caye et al., Hematologica 2012). In 206 cases we additionally used MLPA (P335 SALSA MLPA kit IKZF1, MCR Holland, The Netherlands) to identify whole IKZF1 deletions not detectable by multiplex-PCR. Results In total, 132 IKZF1 alterations were identified in 109/270 cases (40.3%). With regard to ALL subtypes in c-ALL 47.7% (94/197) IKZF1 mutations were detected, in Pro-B ALL 23.5% (12/51) and in three of five Pre-B ALL cases. No IKZF1 deletions were detected in mature B-ALL and thus were mutually exclusive with MYC rearrangements. There was no significant difference in age, sex, leukocyte count, hemoglobin level or platelet count between patients with or without IKZF1 deletions, respectively. With regard to immunophenotype cases with IKZF1 deletions had a stronger expression of CD13 (38±28% vs. 27±25% positive cells; p=0.004), CD33 (24±23% vs. 17±21%; p=0.008), CD34 (72±25% vs. 43±35%; p<0.001%) and TdT (61±28% vs. 43±32%; p<0.001). In 86/109 cases (78.9%) one (monoallelic) intragenic IKZF1 deletion was detected by multiplex-PCR and MLPA. In detail, 38 patients (34.9%) showed deletions of exon 4-7, 15 cases (13.7%) deletions of exon 2-7, 5 cases (4.6%) deletions of exon 4-8 and 3 cases (1.8%) deletions of exon 2-8. In one case, a deletion of IKZF1 exons 2 and 3 was detected by MLPA. 23/109 cases (21.1%) showed two (biallelic) IKZF1 deletions. Whole IKZF1 gene deletions were detected by MLPA in 24/109 cases (22.0%) and were associated with cytogenetic abnormalities of the short arm of chromosome 7 in 21/40 cases (52.5%) including: monosomy 7 (n=14), i(7)(q10) (n=2), dicentric chromosomes 7 (n=1), and unbalanced translocations involving chromosome 7 (n=4). Four of 24 cases with MLL-rearrangements harbored IKZF1 deletions, three of these being whole IKZF1 gene deletions due to monosomy 7. IKZF1 deletions were highly associated with BCR-ABL1 positivity: 72/97 BCR-ABL1pos (74.2%) versus 37/172 BCR-ABL1neg cases (21.5%) (p<0.001). 61/85 cases (71.8%) with intragenic IKZF1 deletions were BCR-ABL1pos compared to 11/24 (45.8%) cases with whole IKZF1 deletions (p=0.018). In 97 BCR-ABL1pos cases, the additional presence of IKZF1 deletions was correlated to inferior survival (p=0.070). Conclusions 1) IKZF1 deletions were detected in 40.3% in adult B-ALL by using muliplex-PCR and MLPA. 2) Whole but also intragenic IKZF1 deletions are highly associated with BCR-ABL1 in adult B-ALL. 3) As 22% of IKZF1 deletions were whole gene deletions not detectable by standard multiplex-PCR, at least two molecular methods (multiplex-PCR and MLPA) are required to fully detect the whole spectrum of IKZF1 deletion patterns in adult B-ALL. Disclosures: Fasan: MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Ulke:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Possible Biomarkers To Predict Response In Patients With Myelodysplastic Syndromes (MDS) Or Acute Myeloid Leukemia (AML) Treated With 5-Azacitidine

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2757-2757 ◽  
Author(s):  
Andrea Kuendgen ◽  
Catharina Müller-Thomas ◽  
Petra Urbaniak ◽  
Michael Lauseker ◽  
Torsten Haferlach ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Research Funding ◽  
Response Rate ◽  
Normal Karyotype ◽  
Allogeneic Transplantation ◽  
Chromosome 7 ◽  
P Value ◽  
Complex Karyotype ◽  
Employment Equity ◽  
Equity Ownership

Abstract Introduction Azacitidine (aza) was the first drug to demonstrate a survival benefit for MDS patients (pts) in a randomized trial [Fenaux, Lancet Oncol 2009]. However, only about half of the pts respond and even after achieving complete remission (CR) and with sustained treatment, pts usually relapse. To date, limited data is available on prognostic factors influencing response. Therefore, until now we have analyzed 71 pts with MDS or AML, treated with at least 3 cycles of aza, to identify prognostic indicators that might help to improve treatment decisions. Patients and Methods 71 cases were included and characterized by cytogenetics and various molecular assays including sensitive next-generation sequencing for mutations in ASXL1, DNMT3A, EZH2, FLT3-LM, IDH1, IDH2, KRAS, MLL-PTD, NRAS, RUNX1, SF3B1, SRSF2, TET2, and TP53. Median age was 71 (50-84) years. 38 pts had MDS (8 RAEB I, 26 RAEB II, 4 RCMD), 28 had AML (6 dysplastic, 16 sAML/MDS, and 6 tAML/MDS), and 5 pts had MDS/MPD. The IPSS [Greenberg, Blood 1997] was low in one, intermediate (int) 1 in 4, int 2 in 26, and high in 14 pts. Regarding cytogenetic risk groups we found 39 low, 11 int and 20 high risk pts according to IPSS and 49 int vs 21 high risk pts according to AML criteria [Grimwade, Blood 2010]. Median time from diagnosis to treatment was 122 days (0-2348). With a median follow up of 1091 days from start of treatment median survival was 530 days (95% CI 412-874). Pts received a median number of 6 cycles (3-43). 12 pts have received allogeneic transplantation after aza treatment and were censored at that date. To assess the impact of biomarkers, Kaplan-Meier curves and Cox models were estimated from the first day of treatment. Variables were considered for multivariate analysis if the univariate p value was <0.1. Results Regarding cytogenetics, 47% of pts exhibited a normal karyotype, 17% had chromosome 7 abnormalities, 13% of karyotypes included del5q, 13% +8, 7% del20q, and 13% were complex. All except one case showed molecular aberrations. The most frequently mutated gene was ASXL1 (42%), followed by RUNX1 (38%), SRSF2 (38%), TET2 (30%), TP53 (18%), DNMT3A (16%), IDH2 (13%), NRAS (13%), EZH2 (12%), SF3B1 (11%), IDH1 (9%), FLT3-ITD (8%), MLL-PTD (7%), and KRAS (6%). Responses were observed in 33 pts (46%; 4 CR, 3 marrow CR with hematological improvement, 8 partial remission, and 18 HI). When cytogenetic abnormalities were examined, responses were seen in 45% of pts with normal karyotype, in 50% of pts with chromosome 7 aberrations, in 33% with del5q, in 67% with +8, in 56% with complex karyotype, and in all 5 cases with del20q (p=0.02). Regarding molecular abnormalities response rate was highest in pts with mutations in NRAS (67%) and IDH2 (63%), followed by RUNX1 (56%), ASXL1 (54%), SF3B1 (43%), TP53 (42%), SRSF2 (36%), TET2 (30%), DNMT3A (30%), MLL-PTD (25%), KRAS (25%), FLT3-ITD (20%), IDH1 (17%), and EZH2 (13%). However none of these mutations had a significant impact on response rate, possibly due to limited statistical power. The only p-value <0.1 was seen for EZH2 (p=0.08). Finally we analyzed the influence of prognostic markers on survival in aza treated pts. In univariate analysis potential candidate variables were: TP53 (p=<0.01, HR: 3.63), cytogenetic group according to AML (p=0.02, HR 2.02) or IPSS (p=0.07, HR (high-low) 1.92, (int-low) 0.86), complex karyotype (p<0.01, HR: 3.17), age [yrs] (p=0.01, HR: 1.08), Hb [g/dl] (p=0.078, HR: 0.836), time to start of aza [yrs] (p=0.01, HR: 0.753), MLL-PTD (p=0.07, HR: 2.87), and AML vs MDS (p=0.01, HR: 2.13). In multivariate analysis TP53 retained a significant influence on survival (HR: 4.99 [CI: 2.20-11.31], p<0.01), accompanied by age (HR:1.10 [CI: 1.03-1.16], p<0.01), Hb (HR: 0.69 [CI: 0.52-0.93], p=0.01), AML vs. MDS (HR: 2.42 [CI: 1.21-4.84], p=0.01), and time to start of aza (HR: 0.70 [CI: 0.52-0.94], p=0.02). TP53 mutations negatively influenced survival, although response rates were comparable to other pts. Response duration was often short. However, pts might still benefit from aza treatment, if combination therapy (e.g. lenalidomide in del5q and TP53 positive pts) or allogeneic transplantation consolidate and prolong treatment results Conclusion After the analysis of 71 pts, TP53 mutations represent the only somatic mutations with a significant negative impact on survival in aza treated pts. The small group of pts with del20q might have higher response rates. The analysis of further pts is ongoing. Disclosures: Kuendgen: Celgene: Honoraria, Research Funding. Off Label Use: Azacitidine in AML >30% marrow blasts. Lauseker:Celgene: Honoraria. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Alpermann:MLL Munich Leukemia Laboratory: Employment. Albuquerque:MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Gattermann:Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Germing:Celgene: Honoraria, Research Funding. Götze:Celgene Corp: Honoraria.

Investigation Of Seven Genes Commonly Deleted In 271 Adult ALL Patients: Association With Cytogenetics and Clinical Features

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2611-2611
Author(s):  
Annette Fasan ◽  
Claudia Haferlach ◽  
Madlen Ulke ◽  
Wolfgang Kern ◽  
Torsten Haferlach ◽  
...  
Keyword(s):  
Clinical Features ◽  
B Lymphocyte ◽  
Fusion Gene ◽  
Normal Karyotype ◽  
Chromosome 9 ◽  
Prognostic Impact ◽  
Employment Equity ◽  
Low Frequencies ◽  
Gene Deletions ◽  
Equity Ownership

Abstract Introduction Recent genomic studies have shown that copy number abnormalities (CNA) of genes involved in B-lymphocyte development and differentiation, cell cycle control and in hematopoiesis are common in B-precursor-ALL (B-ALL). Partial or complete deletions of the IKZF1 gene are frequently detected, especially in patients harboring the BCR-ABL1 fusion gene. Furthermore, several other gene deletions, such as in PAX5, ETV6, RB1, BTG1 and CDKN2A/B have also been described in B- and T-ALL patients. To date, characterization of CNA mainly has focused on pediatric ALL and data on adult ALL are scarce. Aim To evaluate the pattern of CNA in a large cohort of 271 adult ALL cases and their correlation to cytogenetics and clinical features. Patients and Methods We analyzed blood or bone marrow samples of 271 adult ALL cases (B-ALL: n=215; T-ALL: n=56). The B-ALL subgroup comprised 109 females and 106 males, median age was 58.4 years (range: 18.1-89.5 years). The T-ALL group comprised 16 females and 40 males, median age was 38.0 years (range: 18.8-87.7 years). ALL was diagnosed by immunophenotyping. B-ALL cases were classified into seven subgroups according to the following cytogenetics: 1) t(9;22)(q34;q11) (n=63), 2) 11q23/MLL rearrangements (n=21), 3) MYC rearrangements (n=8), 4) hypodiploidy (n=16), 5) hyperdiploidy (n=24), 6) normal karyotype (CN) (n=31), 7) other cytogenetic aberrations (n=35). In 17 cases no cytogenetic data was available. CNA of seven genes were analyzed by multiplex ligation-dependent probe amplification (MLPA) using the SALSA MLPA P335 ALL-KZF1 kit (MCR Holland, The Netherlands). Results Overall, 126/215 (58.6%) of B-ALL patients and 32/56 (57.1%) of T-ALL cases showed deletions (DEL) of at least one of the genes analyzed. In nine cases, amplifications were detected due to chromosomal gains. In the B-ALL cohort the overall occurrence of DEL was as follows: IKZF1: n=85 (39.5%), CDKN2A/B: n=60 (27.9%), PAX5: n=30 (13.9%), RB1: n=13 (6.0%), ETV6: n=7 (3.3%), BTG1: n=5 (2.3%) and EBF1: n=3 (1.4%). 53 (24.5%) patients had one, 33 (15.3%) had two, 23 (10.6%) had three and 17 (7.4%) had four or five deletions. Most DEL were detected in the c-ALL subgroup (n=103/155; 66.5% vs. 23/60, 38.3% of non c-ALL cases). Patients harboring CDKN2A/B or PAX5 DEL were significantly younger compared to patients without these DEL (medain age: 51.8 years vs. 57.2 years; p=0.048 and 47.4 years vs. 57.0 years; p=0.006, respectively). There was no significant association of any DEL with gender, WBC count, hemoglobin levels or platelet count. Patients with BCR-ABL1 rearrangements showed the highest number of DEL (47/63; 74.6%), followed by patients with hyperdiploidy (16/25, 64.0%). The most common DEL in these subgroups were IKZF1 and CDKN2A/B. Fewer DEL were detected in CN cases (9/31, 29.0%) and cases with MLL rearrangements (5/21, 23.8%). Regarding individual abnormalities, of 60 cases with CDKN2A/B DEL, 21 cases showed visible cytogenetic abnormalities of the short arm of chromosome 9 (9p) while 39 cases showed no 9p abnormality. 30/60 cases with CDKN2A/B deletions had additional PAX5 deletions, nine of these showing 9p abnormality. IKZF1 deletions (n=85) were heterogeneous with either the whole gene (n=22) or intrageneic with different exons involved (n=63). RB1 deletions comprised two types: 1) loss of the entire gene (n=5); 2) focal deletions including exons 19-26 (n=8). 11 cases with RB1 deletions harbored concurrent IKZF1 deletions. A negative prognostic impact was shown only for IKZF1 deletions in the cohort of 63 BCR-ABL1pos cases (p=0.07). In the T-ALL cohort, eight patients (14.5%) had one, 18 patients (32.7%) had two, six patients (10.9%) had three and two patients (3.6%) had four deletions. CDKN2A/B (26/55; 47.3%) comprised the most frequent DEL, with 15 of these cases showing visible abnormalities of 9p. Other DEL occurred with low frequencies. T-ALL patients with gene deletions were significantly younger (median 40.6 years vs. 52.2 years; p=0.045). There was no difference in WBC, hemoglobin, platelet counts or survival. Conclusions 1) MLPA is a useful tool to further genetically characterize adult ALL. 2) The pattern of DEL in ALL cases is heterogenous with IKZF1, CDKN2A/B and PAX5 comprising the most frequent aberrations. 3) We were able to confirm the association between distinct DEL and specific cytogenetic subgroups. 4) In both B- and T-ALL DEL were associated with younger age. Disclosures: Fasan: MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Ulke:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Characterization of CMML with Normal Karyotype in Comparison to CMML with Aberrant Karyotype

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1674-1674
Author(s):  
Claudia Haferlach ◽  
Manja Meggendorfer ◽  
Wolfgang Kern ◽  
Susanne Schnittger ◽  
Torsten Haferlach
Keyword(s):  
Chromosome Banding ◽  
Array Cgh ◽  
Negative Impact ◽  
Normal Karyotype ◽  
Employment Equity ◽  
Monosomy 7 ◽  
Cytogenetic Abnormalities ◽  
Banding Analysis ◽  
Chromosome Banding Analysis ◽  
Equity Ownership

Abstract Background: CMML is a myelodysplastic/myeloproliferative neoplasm with distinct morphological and genetic features. Based on differences in blast count CMML is divided into CMML-1 (<1% blasts in the peripheral blood (pB) and <10% in the bone marrow (BM)) and CMML-2 (5-19% blasts in pB, 10-19% in BM or presence of Auer rods). Clonal cytogenetic abnormalities are detected in only 20-40% of patients by chromosome banding analysis (CBA) while >90% of patients harbor at least one molecular mutation. The most frequent cytogenetic abnormalities include abnormalities of chromosome 7, trisomy 8 and complex karyotype. The genes most frequently mutated in CMML are TET2, ASXL1 and SRSF2. Aims: 1. Evaluate the frequency of submicroscopic gains and losses of chromosomal material as well as copy neutral loss of heterozygosity (CN-LOH) in CMML with normal karyotype in chromosome banding analysis (CBA). 2. Analyze the association of these lesions with molecular mutations and impact on survival. Patients and Methods: 69 patients with CMML-1 and 31 with CMML-2 and normal karyotype by CBA were evaluated by array CGH (SurePrint G3 ISCA CGH+SNP, Agilent, Waldbronn, Germany). 32 patients were female, 68 male, median age was 75 years (range: 50-89 years). These were compared to 41 cases with aberrant karyotype by CBA. Patients were screened for mutations (mut) in ASXL1, CBL, DNMT3A, EZH2, JAK2 V617F, KITD 816, KRAS, NRAS, RUNX1, SETBP1, SF3B1, SRSF2, TET2, and U2AF1. Results: In 35 cases (35%) with normal karyotype by CBA 46 abnormalities were detected by array CGH (CGHpos). These were 6 gains, 17 losses and 23 CN-LOH. No recurrent gain was observed, while recurrent losses of 4q24 (n=2, including TET2) and of 13q14 (n=2) were identified. CN-LOH was recurrently observed on 4q (n=6, including TET2), 11q (n=5, including CBL), 17q (n=4) and 7q (n=2). Mutations were identified at the following frequencies: TET2: 77% (74/96), SRSF2: 56% (54/97), ASXL1: 48% (46/96), RUNX1: 20% (20/98), CBL: 15% (15/97), KRAS: 12% (12/97), JAK2 V617F: 10% (10/98). The following genes were mutated in <10%: NRAS, SETBP1, EZH2, U2AF1, KIT D816, SF3B1, DNMT3A. 85 patients were analysed for all mutations. In median 3 mutations were identified per patient (range 0-6), while only in 1 patient no mutation was detected. 4/5 (80%) cases with 11q CN-LOH harbored a CBL mut and 7/8 (88%) cases with CN-LOH 4q or 4q24 deletion harbored a TET2 mut, indicating that these two gene mutations might contribute in homozygous manner to pathogenesis. NRAS mut were significantly less frequent in CMML CGHpos compared to CGHneg (0% vs 14.3%, p=0.024). Mutations in ASXL1 and RUNX1 frequently occurred together: 35% of ASXL1 mut cases also carried a RUNX1 mut as compared to 8% of ASXL1 wild-type cases (p=0.002). All 7 SETBP1 mut cases also carried an ASXL1 mut (p=0.04) Patients with CGHneg (n=65) and CGHpos (n=35) were compared to 41 cases with aberrant karyotype by CBA. While TET2 mut were detected at comparable frequencies in CGHneg and CGHpos patients (80% and 71%) they were significantly less frequent in CMML with aberrant karyotype (54%, p=0.021). On the other hand SETBP1 mut were more frequent in CMML with aberrant karyotype as compared to CGHpos and CGHneg (21%, 7%, 9%, p=0.08). A distinct mutation profile was identified in 9 patients with monosomy 7 who showed ASXL1 mut in 78%, SETBP1 mut in 75%, CBL mut in 33% and TET2 mut in only 22%. In CMML-2 RUNX1 mut were more frequent than in CMML-1 (33% vs 12%. p=0.008). No differences in overall survival (OS) were observed between patients with CGHneg, CGHpos and aberrant karyotype. However, Cox regression analyses revealed a negative impact on OS for ASXL1 mut (relative risk (RR): 2.4, p=0.027), RUNX 1mut (RR: 2.5, p=0.025) and CMML-2 (RR: 2.2, p=0.02). Conclusions: 1. 35% of CMML cases with normal karyotype based on chromosome banding analysis harbor abnormalities detectable by array CGH. 2. Prognosis in CMML is determined by the molecular mutation profile, cytogenetic abnormalities play a minor role. 3. Mutations in ASXL1 and RUNX1 are associated with a negative impact on survival. 4. The poor prognosis described for monosomy 7 seems to be due to a high frequency of ASXL1 und SETBP1 mutations. 5. Inferior outcome in CMML-2 might be due to a higher frequency of RUNX1 mutations. 6. In CMML a molecular work up including screening for mutations in ASXL1 and RUNX1 provides more relevant prognostic information than chromosome banding analysis and/or array CGH. Disclosures Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Meggendorfer:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Analyses of 81 Chronic Myelomonocytic Leukemia (CMML) for EZH2, TET2, ASXL1, CBL, KRAS, NRAS, RUNX1, IDH1, IDH2, and NPM1 Revealed Mutations In 86.4% of All Patients with TET2 and EZH2 Being of High Prognostic Relevance

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 296-296 ◽  
Author(s):  
Vera Grossmann ◽  
Alexander Kohlmann ◽  
Christiane Eder ◽  
Nicholas C.P. Cross ◽  
Claudia Haferlach ◽  
...  
Keyword(s):  
Candidate Genes ◽  
Chronic Myelomonocytic Leukemia ◽  
Molecular Heterogeneity ◽  
Cell Renewal ◽  
Wild Type ◽  
Employment Equity ◽  
Ras Pathway ◽  
Equity Ownership ◽  
Exon 4 ◽  
Myelomonocytic Leukemia

Abstract Abstract 296 Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic malignancy that is characterized by features of both a myeloproliferative neoplasm and a myelodysplastic syndrome. Recently, we investigated 81 CMML cases (45 CMML-1, 36 CMML-2) diagnosed between 10/2005 - 9/2008, which had been characterized by chromosome banding analysis and mutation analysis in 6 candidate genes: Mutations were detected in TET2 (44.4%), CBL (22.2%), NRAS (22.2%), KRAS (12.3%), JAK2 (9.8%), RUNX1 (8.7%) (Kohlmann et al., J Clin Oncol. 2010 Jul 19). We now applied amplicon-based deep-sequencing using the small volume Titanium chemistry assay (454 Life Sciences, Branford, CT) to investigate additional 4 candidate genes: IDH1 (exon 4), IDH2 (exon 4) and NPM1 (exon 12) (at known mutational hotspot regions) and the complete coding region of EZH2. EZH2 encodes a catalytic subunit of the polycomb repressive complex 2, a highly conserved histone H3 lysine 27 methyltransferase that influences stem cell renewal. Mutations in EZH2 were recently described to play a role in MPN/MDS. The sequencing library preparation for IDH1, IDH2, NPM1, and EZH2, in total 22 amplicons, was performed using 48.48 Access Array technology (Fluidigm, South San Francisco, CA) to cope with the number of amplicons. In median, 498 reads per amplicon were obtained, thus yielding sufficient coverage for detection of mutations with high sensitivity. After excluding polymorphisms and silent mutations aberrations were detected in IDH1 (1/81; 1.2%), IDH2 (3/81; 3.7%), NPM1 (1/81; 1.2%), and EZH2 (10/81; 12.3%). Another gene recently described in hematological diseases is ASXL1 (additional sex combs like 1) on chromosome 20q11.1. Therefore, the hotspot region of ASXL1 exon 12 was additionally investigated by Sanger sequencing in those 20 cases, in which no mutation had been observed thus far. Nine of these 20 cases (45%) harbored a mutation in ASXL1, thus only 11 cases (13.6%) remained in this cohort in which no mutation was detected. Summarizing this data, 86.4% of these CMMLs harbored at least one molecular aberration with a median of two genes mutated (range 1–4). In more detail, we observed 11 novel distinct EZH2 mutations in ten patients: 7 missense, 3 frameshifts (2 deletions, 1 insertion), and one splice site mutation. EZH2 mutations were found to be heterogeneous and were spread over several exons, predominantly located in the four conserved regions (6/11 in the conserved SET domain; e.g. H680R, N659S). No case revealed a Tyr641 of EZH2 mutation as described for follicular and diffuse large B-cell lymphomas. In median, the burden of EZH2 mutations was 42.5% of sequencing reads per patient (range 1.4–98%). Similarly, a high mutation burden was detected in RUNX1 (median 46.7%), TET2 (median 44.6%), and CBL (median 42.5%) whereas the burden was low in RAS pathway alterations, i.e. NRAS (median 11.1%), KRAS (median 27%), or JAK2 V617F mutations (median 6.9%). With respect to associations of distinct mutations no specific pattern was observed, i.e. EZH2 mutations were concomitantly detected with TET2 (4/10), RUNX1 (3/10), CBL (3/10), JAK2 (3/10), NRAS (2/10), KRAS (1/10), and IDH2 (1/10), respectively. Further, EZH2 mutations were associated neither with morphologic CMML subtype or dysplastic or myeloproliferative characteristics nor with age, white blood cell count, thrombocytes count, or hemoglobin. However, with respect to clinical data a very poor outcome was observed for patients that carried EZH2 mutations compared to EZH2 wild-type cases (median OS 4.3 vs. 130.4 months; p<0.001). In contrast, a significantly better outcome was seen for patients who carried TET2 mutations compared to TET2 wild-type cases (median OS 130.4 vs. 53.6 months, p=0.013). Subsequently, we performed a survival analysis taking both EZH2 and TET2 mutations into account. Here, the cohort was significantly separated into three distinct prognostic groups, i.e. EZH2-mutated with a poor median OS of 4.3 months, EZH2/TET2 wild-type with a median OS of 90 months and TET2-mutated cases with a median OS of 130.4 months (p<0.001). In conclusion, our study revealed molecular mutations in 86.4% of 81 CMML patients providing new insights into the molecular heterogeneity of this disease. Besides alterations in TET2, CBL, ASXL1, and the RAS pathway, EZH2 is targeted by various types of frameshift and point mutations and is a novel biomarker with unfavorable prognosis and clinical utility. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Eder:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership, Research Funding. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Genetic and Epigenetic Silencing of Mesoderm Specific Transcript (MEST) In Acute Myelogenous Leukemia.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3639-3639
Author(s):  
Anna R Poetsch ◽  
Rainer Claus ◽  
Lars Bullinger ◽  
Tania Witte ◽  
Michael Lübbert ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Tumor Suppressor ◽  
Cpg Island ◽  
Normal Karyotype ◽  
Epigenetic Silencing ◽  
Myelogenous Leukemia ◽  
Chromosome 7 ◽  
Special Importance ◽  
Monosomy 7 ◽  
Chromosomal Changes

Abstract Abstract 3639 About 10 % of patients with either myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) present either with deletions on the long arm of chromosome 7 or monosomy 7. These chromosomal aberrations are associated with a poor prognosis. Following biallelic inactivation as proposed by Knudsen, a “second hit” of the remaining allele might be required for loss of gene function. Epigenetic silencing might display such a hit in particular since no additional genetic hits could be identified so far. The role of epigenetic regulation might be of special importance in patients with -7/7q-, since several studies have shown that patients harbouring a chromosome 7 abberrations do more benefit from a therapy with demethylating agents as compared to patients with other chromosomal changes. To address the issue of epigenetic silencing in these AML cases we utilized DNA methylation profiling to identify the potential tumor suppressor genes on chromosome 7. We used MBD2 based enrichment of methylated DNA from 4 AML patient samples with monosomy 7 and from 23 patient samples with with other chromosomal changes including normal karyotype AML. For validation we analyzed regional DNA methylation using quantitative MassArray technology on DNA from 115 del(7q) AML or monosomy 7 patients as well as normal karyotype patients (n=20) and CD34 + cells from healthy individuals (n=5). We could identify the gene MEST to be silenced by hypermethylation (> 30 %) of a CpG island on the remaining allele in 20% of the patients with -7/7q- and 40% of patients with normal karyotype. Thus, preferentially in patients that do not have a deletion already. MEST is an imprinted gene located on 7q32.2. However, silencing is correlated with hypermethylation of a CpG island located at an alternative promoter of MEST, independent of the methylation status of the imprinting control region. In two patient samples with monosomy 7 and hypermethylation of MEST (> 80%), DNA methylation was erased after 5-Aza-2′-deoxycytidine (DAC) treatment to less than 10 %. In concordance, also AML cell lines with hypermethylation of the MEST locus loose methylation after sublethal DAC treatment which leads to a reexpression of the gene. Thus, we hypothesize that MEST functions as a tumor suppressor in AML and is genetically as well as epigenetically silenced AML. Reactivation of MEST by demethylating treatment may contribute to the mechanism by which demethylating drugs display their therapeutic potential in leukemia. Disclosures: No relevant conflicts of interest to declare.

Impact of Expression of BAALC, CDKN1B, ERG, EVI1, and MN1 on Prognosis and Their Association with Karyotype, FLT3-ITD, NPM1 and MLL-PTD Status In Adult AML: A Comprehensive Study on 286 Cases

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 953-953
Author(s):  
Claudia Haferlach ◽  
Alexander Kohlmann ◽  
Sonja Schindela ◽  
Tamara Alpermann ◽  
Wolfgang Kern ◽  
...  
Keyword(s):  
Molecular Genetic ◽  
Normal Karyotype ◽  
Genetic Alterations ◽  
Complex Karyotype ◽  
Employment Equity ◽  
Aberrant Expression ◽  
Cox Regression Analysis ◽  
Total Cohort ◽  
Equity Ownership ◽  
Low Expression

Abstract Abstract 953 Introduction: The WHO classification in 2008 listed for the first time aberrant expression of genes as molecular genetic alterations affecting outcome in AML. High expression of BAALC, ERG and MN1 were shown thus far to be associated with unfavorable outcome in normal karyotype AML (AML-NK). In addition high EVI1 expression was suggested to predict poor outcome. Recently, our group identified low expression of CDKN1B as a favorable prognostic marker. The aim of this study was to evaluate the expression of BAALC, CDKN1B, ERG, EVI1 and MN1 in AML comprising all cytogenetic risk groups with respect to their association with distinct cytogenetic and known molecular genetic subgroups and their impact on prognosis. Patients/Methods:: Expression levels of BAALC, CDKN1B, ERG, EVI1 and MN1 were determined by oligonucleotide microarrays (HG-U133 Plus 2.0, Affymetrix) in 286 AML (t(15;17) n=15; t(8;21) n=16; inv(16) n=7; normal karyotype n=99; 11q23/MLL-rearrangements n=10; complex karyotype n=51; other abnormalities n=88). Patients were further analyzed for mutations in NPM1, FLT3-ITD, CEPBA and MLL-PTD. Results: Expression of BAALC, CDKN1B, ERG, EVI1 and MN1 varied significantly between genetic subgroups: While t(15;17), t(8;21) and 11q23/MLL-rearrangements were associated with low CDKN1B expression, AML-NK and NPM+ cases showed a higher CDKN1B expression. Lower BAALC expression was observed in AML with t(15;17), 11q23/MLL-rearrangement and AML-NK as well as in FLT3-ITD+ AML and in NPM1+ AML, while in AML with other abnormalities a higher BAALC expression was observed. ERG expression was lower in AML with 11q23/MLL-rearrangement and normal karyotype, while it was higher in AML with complex karyotype. Low EVI1 expression was observed in AML with t(15;17), t(8;21), inv(16) and AML-NK, while it was higher in AML with 11q23/MLL-rearrangements. Low MN1 expression was associated with t(15;17), t(8;21) and AML-NK, while it was increased in cases with inv(16) or other abnormalities. Next, Cox regression analysis was performed with respect to overall survival (OS) and event free survival (EFS). In the total cohort high BAALC and ERG expression as continuous variables were associated with shorter OS and EFS while CDKN1B, EVI1 and MN1 had no impact. Furthermore the cohort was subdivided into quartiles of expression for each gene. After inspection of the survival curves the cut-off for high vs low expression was set as follows: BAALC: 75th percentile, CDKN1B: 25th percentile, ERG and MN1: 50th percentile. For EVI1 expression pts were separated into expressers (n=44) and non-expressers (n=242). Low CDKN1B expression was associated with longer OS and EFS in the total cohort (p=0.005, not reached (n.r.) vs 14.9 months (mo); p=0.013, 31 vs 9.7 mo). High BAALC expression had no impact on OS, but was associated with shorter EFS in the total cohort as well as in AML with intermediate cytogenetics and AML with other abnormalities (p=0.032, 6.2 vs 13.0 mo; p=0.027, 5.1 vs 11.3 mo; p=0.006, 2.3 vs 14.8 mo). High ERG expression was significantly associated with shorter OS and EFS in the total cohort (p=0.002, 12.5 mo vs n.r.; p=0.001, 8.1 vs 15.7 mo) as well as in AML-NK (p=0.001, 11.3 mo vs n.r.; p=0.010, 7.2 vs 22.1 mo). OS was also shorter in AML with unfavorable karyotype (p=0.048, median OS 9.3 mo vs n. r.). With respect to MN1 high expressers had a significantly shorter OS and EFS in the total cohort (p=0.004, 12.3 mo vs. n.r.; p=0.001, 8.1 vs 16.7 mo) as well as in AML-NK (p=0.001, 9.7 mo vs n.r.; p=0.001, 5.1 vs 22.1 mo). In a multivariate analysis including CDKN1B, ERG and MN1 all parameters retained their impact on OS as well as on EFS, while BAALC lost its impact on EFS. Adding MLL-PTD, NPM1+/FLT3-ITD-, favorable and unfavorable karyotype into the model demonstrated an independent significant adverse impact on OS for MLL-PTD (p=0.027, relative risk (RR): 2.38) and ERG expression (p=0.044, RR: 1.59) only. In the respective analysis for EFS only favorable karyotype showed an independent association (p=0.002, RR: 0.261). Conclusion: 1) Expression of BAALC, CDKN1B, ERG, EVI1 and MN1 varies significantly between cytogenetic subgroups. 2) BAALC as a continuous variable and CDKN1B, ERG and MN1 as dichotomized variables are independently predictive for OS and EFS in AML. 3) ERG expression even retains its independent prediction of shorter OS if cytogenetic and other molecular genetic markers are taken into account. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Schindela:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Whole-Exome Sequencing Identifies Recurrent Mutations of BCOR in Acute Myeloid Leukemia with Normal Karyotype

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 71-71 ◽  
Author(s):  
Brunangelo Falini ◽  
Vera Grossmann ◽  
Enrico Tiacci ◽  
Antony Holmes ◽  
Alexander Kohlmann ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Exome Sequencing ◽  
Myeloid Leukemia ◽  
Normal Karyotype ◽  
Employment Equity ◽  
Normal Cells ◽  
Genetic Syndrome ◽  
Whole Exome ◽  
Equity Ownership ◽  
Acute Myeloid

Abstract Abstract 71 Acute myeloid leukemia (AML) with normal cytogenetics (CN-AML) represents about half of all adult AML. NPM1 and CEBPA mutations define WHO provisional entities accounting for ∼60% of CN-AML, but the remaining cases (∼40%) remain poorly characterized. To address this issue, we carried out whole-exome-sequencing (WES) of leukemic and normal cells from one patient with CN-AML that lacked mutations in NPM1, CEBPA, FLT3-ITD, and MLL-PTD. Using this approach, we identified a clonal somatic mutation of BCOR, a gene located on chromosome Xp11.4, that was present in the leukemic but not normal cells of the index AML case. The BCOR (BCL6 co-repressor) gene encodes for an ubiquitously expressed nuclear protein that is involved in repressing the activity of BCL6 and other transcriptional factors. BCOR is a key transcriptional regulator of early embryonic development, mesenchymal stem cell function and hemopoiesis. Germline mutations of BCOR are responsible for the oculo-facio-cardio-dental (OFCD) genetic syndrome that is inherited in an X-linked pattern and comprises microphtalmia, dysmorphic appearance, dental abnormalities (radiculomegaly), hammer-toe deformity and cardiac defects. WES findings in the index case were subsequently validated and further studied in a total cohort of 514 AML patients. We first performed deep-sequencing analyses of all exons of the BCOR gene in an initial set of 82 AML cases that were selected because they showed the same genetic characteristics of our index patient (i.e. normal karyotype without NPM1, CEBPA, FLT3-ITD and MLL-PTD mutations). Disruptive BCOR mutations (i.e., nonsense mutations, out-of-frame small indels, and consensus splice-site mutations) were detected in 14/82 (17.1%) of these cases. We next assessed the frequency of BCOR mutations in a series of unselected CN-AML patients (n=262) and found that they occurred in 4.2% of cases, mostly showing the typical features of BCOR-mutated cases (absence of NPM1, CEBPA, FLT3-ITD and MLL-PTD mutations). Almost mutual exclusion of BCOR and NPM1 mutations was further confirmed in a separate series of 71 NPM1-mutated only AML patients. No BCOR mutations were observed in the 89 AML cases with recurrent cytogenetic abnormalities investigated, including t(8;21)(q22;q22) (n= 29), inv(16)(p13q22) (n=40), t(15;17)(q22;q12) (n=10), and t(11q23)/MLL (n=10), and in the 10 patients with double CEBPA-mutated AML studied. BCOR mutations were: i) scattered across the whole length of the coding sequence with no hotspots identified; ii) somatic in origin and disruptive molecular events similar to germline BCOR mutations causing the OFCD genetic syndrome; iii) associated with markedly decreased BCOR mRNA levels, absence of full-length BCOR and absent or low expression of a truncated BCOR protein; iv) almost mutually exclusive with NPM1 (only 1.5% of the 197 NPM1-mutated AML investigated carried BCOR mutations); v) rarely associated with FLT3-ITD; and vi) frequently associated with DNMT3A and RUNX1 mutations, suggesting cooperation with the respective mutated pathways. Clinically, BCOR mutations correlated with poor outcome among the cohort of 160 CN-AML patients evaluated (28.0% versus 66.3% overall survival at 2 years, P=0.024). We also searched for BCOR mutations in the human AML cell lines OCI-AML2, OCI-AML3, KG1a, U937, HL-60, HL-60R, HB4, AML193, and MVP-11. Only HL-60 and HL-60R (a ATRA-resistant derivative of HL-60) carried a BCOR mutation that consisted of a hemizygous G to T transition at position 4616 in exon 10, leading to the Glu1442X nonsense mutation. Western blot analysis of HL-60 cells resulted in the absence of the full-length BCOR protein (predicted MW: 192 kDa) and presence of a low intensity 156 kDa band likely corresponding to a truncated BCOR protein. In conclusion, our results implicate for the first time BCOR in the pathogenesis of CN-AML and suggest it may act as tumor suppressor gene. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Array CGH Identifies Copy Number Changes In 10% Of 520 MDS Patients With Normal Karyotype: Deletions Encompass The Genes TET2, DNMT3A, ETV6, NF1, RUNX1, and STAG2 and Are Associated With Shorter Survival

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1516-1516
Author(s):  
Claudia Haferlach ◽  
Melanie Zenger ◽  
Marita Staller ◽  
Andreas Roller ◽  
Kathrin Raitner ◽  
...  
Keyword(s):  
Copy Number ◽  
Chromosome Banding ◽  
Array Cgh ◽  
Normal Karyotype ◽  
Employment Equity ◽  
Interphase Fish ◽  
Banding Analysis ◽  
Chromosome Banding Analysis ◽  
Equity Ownership ◽  
Copy Number Changes

Abstract Background In MDS, cytogenetic aberrations play an important role for classification and prognostication. The original IPSS and the revised IPSS classifiers have clearly demonstrated the prognostic impact of distinct cytogenetic abnormalities. The vast majority of chromosome aberrations in MDS are gains or losses of chromosomal material while balanced rearrangements are rare. However, more than 50% of MDS and even more in low risk MDS harbor a normal karyotype. Chromosome banding analysis can only detect gains and losses of more than 10 Mb size due to its limited resolution and is dependent on proliferation of the MDS clone in vitro to obtain metaphases. Array CGH has a considerably higher resolution and does not rely on proliferating cells. Aims In this study we addressed the question whether MDS with normal karyotype harbor cytogenetically cryptic gains and losses. Patients and Methods 520 MDS patients with normal karyotype were analyzed by array CGH (Human CGH 12x270K Whole-Genome Tiling Array, Roche NimbleGen, Madison, WI). For all patients cytomorphology and chromosome banding analysis had been performed in our laboratory. The cohort comprised the following MDS subtypes: RA (n=22), RARS (n=43), RARS-T (n=27), RCMD (n=124), RCMD-RS (n=111), RAEB-1 (n=104), and RAEB-2 (n=89). Median age was 72.2 years (range: 8.9-90.1 years). Subsequently, recurrently deleted regions detected by array CGH were validated using interphase-FISH. Results In 52/520 (10.0%) patients copy number changes were identified by array CGH. Only eight cases (1.5%) harbored large copy number alterations >10 Mb in size, as such generally detectable by chromosome banding analysis. These copy number alterations were confirmed by interphase-FISH. They were missed by chromosome banding analysis due to small clone size (n=2), insufficient in vitro proliferation (n=3) or poor chromosome morphology (n=3). In the other 44 patients with submicroscopic copy number alterations 18 gains and 32 losses were detected. The sizes ranged from 193,879 bp to 1,690,880 bp (median: 960,176 bp) in gained regions and 135,309 bp to 3,468,165 bp (median: 850,803 bp) in lost regions. Recurrently deleted regions as confirmed by interphase-FISH encompassed the genes TET2 (4q24; n=9), DNMT3A (2p23; n=3), ETV6 (12p13; n=2), NF1 (17q11; n=2), RUNX1 (21q22; n=2), and STAG2 (Xq25, deleted in 2 female patients). No recurrent submicroscopic gain was detected. In addition, we performed survival analysis and compared the outcome of patients with normal karyotype also proven by array CGH (n=462) to patients with aberrant karyotype as demonstrated by array CGH (n=52). No differences in overall survival were observed. However, overall survival in 35 patients harboring deletions detected solely by array CGH was significantly shorter compared to all others (median OS: 62.1 vs 42.4 months, p=0.023). Conclusions 1. Array CGH detected copy number changes in 10.0% of MDS patients with cytogenetically normal karyotype as investigated by the gold standard method, i.e. chromosome banding analysis. 2. Most of these alterations were submicroscopic deletions encompassing the genes TET2, ETV6, DNMT3A, NF1, RUNX1, and STAG2. 3. Interphase-FISH for these loci can reliably pick up these alterations and is an option to be easily performed in routine diagnostics in MDS with normal karyotype. 4. Patients harboring deletions detected solely by array-CGH showed worse prognosis. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Zenger:MLL Munich Leukemia Laboratory: Employment. Staller:MLL Munich Leukemia Laboratory: Employment. Roller:MLL Munich Leukemia Laboratory: Employment. Raitner:MLL Munich Leukemia Laboratory: Employment. Holzwarth:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Apixaban Reduces Hospitalization In Patients With Venous Thromboembolism: An Analysis Of The AMPLIFY-EXT Trial

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3638-3638 ◽  
Author(s):  
Xianchen Liu ◽  
John Thompson ◽  
Hemant Phatak ◽  
Jack Mardekian ◽  
Anthony R. Porcari ◽  
...  
Keyword(s):  
Placebo Group ◽  
Venous Thromboembolism ◽  
Controlled Trial ◽  
Anticoagulation Therapy ◽  
Cox Proportional Hazards ◽  
Employment Equity ◽  
Double Blind ◽  
Significant Difference ◽  
Equity Ownership

Abstract Introduction Venous thromboembolism (VTE) is associated with a considerable risk for morbidity and recurrence and related hospitalizations. In the Apixaban after the Initial Management of Pulmonary Embolism and Deep Vein Thrombosis with First-Line Therapy-Extended Treatment (AMPLIFY-EXT) trial, a double-blind placebo-controlled trial with 12 months of treatment, two doses of apixaban (2.5 mg and 5 mg, twice daily) versus placebo significantly reduced symptomatic recurrent VTE or all-cause death without increasing the rate of major bleeding among 2,482 VTE patients who had completed 6-12 months of anticoagulation therapy. In this study, the effects of apixaban therapy versus placebo on medical hospitalization during AMPLIFY-EXT trial were evaluated. Methods A total of 2,477 patients who received study drugs were included in the analysis. All-cause hospitalizations during the trial were captured by dedicated case report forms. Outcomes of interest were; rate of hospitalizations and time from randomization to the first hospitalization. Patients were censored at either death, loss to follow-up, or end of study, whichever came first. Effects of treatment with apixaban versus placebo on the rates of hospitalization were assessed using Cox proportional hazards regression models. Results During a mean follow-up of 12.3 months, 138 patients were hospitalized at least once, 62 (7.5%/year) in the placebo group (n=826), 42 (4.8%/year) in the apixaban 2.5 mg group (n=840), and 34 (4.0%/year) in the apixaban 5 mg group (n=811). Compared with placebo, apixaban 2.5 mg [hazard ratio (HR) 0.65, 95% confidence interval (CI) 0.44–0.96; p=0.030] and 5 mg (HR 0.54, 95%CI 0.36–0.83, p=0.004) were both associated with significant reduction in hospitalization. There was no significant difference in hospitalizations between the 2 doses of apixaban (5 mg vs. 2.5 mg: HR 0.84, 95%CI 0.53–1.32, p=0 .445). The mean time to first hospitalization was 153.7 days in the placebo group, 196.9 days in the apixaban 2.5 mg group, and 202.4 days in the apixaban 5 mg group (Figure). Conclusions Extended anticoagulation with apixaban at either a dose of 5 mg or 2.5 mg significantly reduced the risk of hospitalization, possibly due to the reduction in VTE recurrence. Disclosures: Liu: Pfizer: Employment, Equity Ownership. Thompson:Pfizer: Employment, Equity Ownership. Phatak:BMS: Employment, Equity Ownership. Mardekian:Pfizer: Employment, Equity Ownership. Porcari:Pfizer: Employment, Equity Ownership. Johnson:Pfizer: Employment, Equity Ownership.

Gene Amplifications In 84 Patients With Acute Myeloid Leukemia and 31 Patients With Myelodysplastic Syndrome Investigated By Array CGH

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3724-3724
Author(s):  
Andreas Roller ◽  
Simone Weber ◽  
Alexander Kohlmann ◽  
Melanie Zenger ◽  
Marita Staller ◽  
...  
Keyword(s):  
Array Cgh ◽  
Chromosomal Abnormalities ◽  
Ring Chromosome ◽  
Normal Karyotype ◽  
Structural Type ◽  
Single Copy ◽  
Chromosome 8 ◽  
Complex Karyotype ◽  
Employment Equity ◽  
Equity Ownership

Abstract Background Gains and losses of chromosomal material are frequent in AML and MDS and usually lead to loss or gain of a single copy of a whole chromosome, a chromosome arm or small stretches of the chromosome that may be microscopically invisible. More rarely, amplifications of chromosomal regions (defined as the presence of more than 6 copies of a region per cell) are observed. These supernumerary copies are located either extrachromosomally as small acentric chromosomal structures - so called double-minutes (dmin) - or intrachromosomally as large contiguous stretches of amplified DNA, so called homogeneously staining regions (HSR). Aims Characterize AML and MDS cases with gene amplifications with respect to size, affected genes and accompanying chromosomal abnormalities as well as TP53 status. Patients and Methods 84 AML and 31 MDS cases with cytogenetically visible amplifications were selected for this study. All cases were analyzed by array CGH, chromosome banding analysis, sequencing for TP53 mutations as well as FISH for TP53 deletions. Results The cohort comprised 55 (47.8%) males and 60 (52.2%) females with a median age of 72.0 years (range 38.0 - 90.3 years). A complex karyotype (≥4 aberrations) was present in 92/115 (80.0%) cases (AML=65/84 (77.4%); MDS=27/31 (87.1%)). In total, 385 amplified regions were identified by array CGH. In more detail: 3q26 (AML: n=6; MDS: n=3), 8q24 (AML: n=15; MDS: n=1), 11q21-25 (AML: n=42; MDS: n=13), 13q12 (AML: n=3; MDS: n=1), 13q31 (AML: n=3; MDS: n=2), 19p13 (AML: n=2; MDS: n=4), and 21q21-q22 (AML: n=24; MDS: n=5). The median number of amplified regions was 3 (range 1-18). In 14/115 (12.2%) cases, the amplification was located in dmins (AML: n=11; MDS: n=3) and in 101/115 (87.8%) patients in HSR (AML: n=73; MDS: n=28). In 40 of the latter 101 cases (39.6%) (AML: n=24; MDS: n=16) the amplification was located on a ring chromosome (rc). In patients with complex karyotypes we detected a significantly higher number of amplified regions as compared to non-complex karyotypes (3.5 vs. 2.8; p=0.015). No association between the complexity of the karyotype and the structural type of the amplification (dmin vs rc) was observed. Cases with non-complex karyotypes frequently harbored a 5q deletion (6/23; 26.1%) or chromosome 8 abnormalities (3/23; 13.0%). Within the subgroup of non-complex karyotypes del(5q) cases showed a tendency to a higher number of amplified regions (3.6 vs. 1.9; p=0.140). Further, amplifications of 11q genes were more frequent in complex karyotypes (54.4% vs. 21.7%; p=0.005), whereas 8q amplifications were more frequent in non-complex karyotypes (43.5% vs. 4.4%; p<0.001). We detected a large region on band 11q24, which was amplified in 41/53 (77.4%) cases. This commonly amplified region contains 1,575 genes including the MLL gene. Cases harboring dmins had shorter amplified regions compared to cases with rc (4,428,112.5 bp vs. 18,265,496.9 bp; p=0.028). Moreover, we detected a positive correlation of patients having a rc and gene amplification on chromosome 11q23-25 (p<0.05). On chromosome 3q, 8/9 (88.9%) cases shared a minimal amplified region covering the EVI1 gene. In comparison to samples obtained from healthy donors (n=47), the EVI1 expression was significantly higher in cases with EVI1 amplification (87.4 vs. 0.5; p=0.048). On chromosome 21q the regions of amplifications were heterogeneous. However, we detected a minimal region containing 11 genes including ERG which was amplified in 26/29 (89.7%) patients. ERG expression data was available in 8 cases and was significantly higher compared to a control cohort of AML with normal karyotype (n=331) (729.2 vs. 229.0; p=0.05). On chromosome 8 an amplified region was identified in 15/16 cases. In 14 of these cases (87.5%) the region included MYC. TP53mut were present in 93/115 (80.9%) patients, accompanied by a TP53del in 28/93 (30.1%) cases. Interestingly, cases harboring a TP53mut had more amplified regions compared to TP53wt (3.4 vs. 1.7; p<0.001). Conclusions 1. MLL is the most frequently amplified gene in AML and MDS. 2. Patients with complex karyotypes or TP53mut harbored more amplified regions compared to patients with non-complex karyotypes and TP53wt. 3. Amplifications on 11q were more frequent in complex karyotype whereas gene amplifications on 8q were predominantly observed in non-complex karyotypes. 4. EVI1 and ERG gene amplifications lead to a higher expression of the respective genes. Disclosures: Roller: MLL Munich Leukemia Laboratory: Employment. Weber:MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Zenger:MLL Munich Leukemia Laboratory: Employment. Staller:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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