Comprehensive Cytogenetic and Molecular Genetic Characterization of T-PLL Identifies for the First Time BCOR Mutations in a Lymphatic Disease.

Abstract Abstract 2539 Introduction: T-cell prolymphocytic leukemia (T-PLL) is a rare mature post-thymic T-cell neoplasm with aggressive clinical course and a median overall survival of less than one year. Due to the rareness of this disease (∼2% of cases of mature lymphocytic leukemias in adults) only few cases with cytogenetic and molecular genetic aberrations have been reported so far. However, almost 75% of T-PLL cases are reported to harbor chromosome 14 abnormalities involving the TCRA/D locus resulting in the aberrant activation of the proto-oncogenes TCL1A or MTCP1. Aim: Perform a comprehensive cytogenetic and molecular characterization of T-PLL. Patient and Methods: The cohort comprised 36 T-PLL cases diagnosed between 10/2005 and 07/2012 (23 male, 13 female patients). Median age was 71.0 yrs (range: 26.8–82.8 yrs). According to the WHO classification all T-PLL cases were characterized using immunophenotyping and cytomorphology. Patients were further investigated using chromosome banding analysis (CBA) (n=30), FISH for deletions of ATM (n=30), TP53 (n=29), and 13q (n=26), and CGH arrays (n=3, Human CGH 6×630K Whole-Genome Tiling Array, Roche NimbleGen, Madison, WI). Further, mutation analyses for BCOR and TP53 were performed using amplicon sequencing (Roche 454, Branford, CT). Results: Aberrant karyotypes were observed by CBA in 25/30 cases (83.3%). However, the 5 remaining cases with normal karyotype were due to insufficient proliferation of the T-PLL clone as gains, losses and rearrangements were detected in these 5 cases using FISH analyses. In more detail, combined CBA and FISH data revealed in 20/30 (66.7%) cases an inv(14)(q11q32)/t(14;14)(q11;q32)/TCRA/D-TCL1A (n=18) or t(X;14)(q27;q11)/TCRA/D-MTCP1 (n=2). Further, a gain of chromosome 8q and concomitant loss of 8p was observed in 13/30 (43.3%) cases. In addition, in 10/25 (40.0%) cases a 6q deletion and in 7/25 (28.0%) an 12p deletion were observed. Based on FISH data, deletions were detected of ATM in 19/30 (63.3%) cases, TP53 in 7/29 (24.1%), and 13q in 9/26 (34.6%) cases. In addition, 3 cases were studied using array CGH. Hereby, an intragenic deletion in the BCOR gene was observed in one patient. BCOR is a BCL6 corepressor and located on chromosome Xp11.4. BCOR mutations were recently described in cases with AML. BCOR mutation frequency was determined at 3.8% in AML with normal karyotype and mutations were associated with shorter overall and event-free survival. The deletion in BCOR identified in one of our cases and the TP53 deletions in 7 T-PLL cases prompted us to screen 35 cases for molecular mutations in these two genes. Overall, BCOR mutations were detected in 5/35 (14.3%) patients and TP53 mutations in 4/35 (11.4%) cases. In total, 7 missense, one frame-shift and one nonsense mutations were found. Median mutation load was 90.0% for BCOR (range: 38–100%) and 80.0% (59–87%) for TP53. Next, we performed correlation analyses between mutations in BCOR and TP53, rearrangements involving chromosome 14, deletions of ATM, TP53, 6q, 12p, and 13q and gain of 8q. Here, BCOR was not associated with any of these parameters. In contrast, TP53 mutations were accompanied in all 4 cases by TP53 deletions, while only 3/24 TP53 wild-type cases harbored a TP53 deletion (P=0.002). In addition, only one of 4 TP53 mutated cases harbored a chromosome 14 rearrangement while 18/25 (72%) TP53 wild-type cases did (P=0.105). In line with this result, TP53 deletions were also negatively associated with chromosome 14 rearrangements (2/7 vs 17/22, P=0.030). Further, all cases with a gain of 8q harbored a 14q rearrangement (13/13 vs 8/18 without gain of 8q, P=0.001). Conclusions: 1. CBA, FISH and mutation analysis of TP53 and BCOR revealed genetic abnormalities in all 36 analyzed cases. 2. The most frequent abnormality involved the TCRA/D locus (14q11) (20/30; 66.7%) activating the proto-oncogenes TCL1A on chromosome 14q32 (90.0%) or MTCP1 on chromosome Xq28 (10.0%). 3. Deletions were detected for ATM (63.3%), TP53 (24.1%), 6q (40.0%), 13q (34.6%), 12p (28.0%), and a gain was detected for the long arm of chromosome 8 (43.3%). 3. In addition to the detection of TP53 mutations in 11.4%, BCOR mutations were observed for the first time in a lymphatic malignancy with a mutation frequency of 14.3%. 4. The prognostic relevance of such cytogenetic and molecular genetic aberrations has to be determined in T-PLL, given that in myeloid malignancies both BCOR and TP53 are associated with shorter OS. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Equity Ownership.

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Characterization of MDS Harboring TET2 Mutations and/or TET2 Deletions

Blood ◽

10.1182/blood.v128.22.4288.4288 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4288-4288 ◽

Cited By ~ 1

Author(s):

Claudia Haferlach ◽

Anna Stengel ◽

Manja Meggendorfer ◽

Wolfgang Kern ◽

Torsten Haferlach

Keyword(s):

Overall Survival ◽

Relative Risk ◽

Molecular Genetic ◽

Normal Karyotype ◽

Prognostic Impact ◽

Complex Karyotype ◽

Wild Type ◽

Employment Equity ◽

Total Cohort ◽

Equity Ownership

Background: TET2 mutations and deletions have been reported in MDS. A detailed analysis of the prognostic impact of TET2 deletions and their association to TET2 mutations is lacking. Aim: To characterize MDS with TET2 mutations (mut) and/or TET2 deletions (del) with respect to accompanying cytogenetic and molecular genetic abnormalities and their impact on prognosis. Patients and Methods: First 788 unselected MDS cases (cohort A) were evaluated. As in this cohort only 8 cases with TET2 deletion were detected, further MDS were screened for TET2 deletions. In total 77 MDS harboring a TET2 deletion were identified and included in cohort B. Both cohorts were analyzed by chromosome banding analysis, FISH, genomic arrays and mutation analysis of TET2. Cases from cohort A were also analyzed for mutations in ASXL1, ATM, BCOR, BRCC3, CBL, CTCF, DNMT3A, ETV6, EZH2, FBXW7, IDH1, IDH2, JAK2, KRAS, LAMB4, MPL, NCOR1, NCR2, NF1, NRAS, PHF6, PRPF8, PTPN11, RAD21, RUNX1, SETBP1, SF3B1, SMC3, SRSF2, STAG2, TET2, TP53, U2AF1 and ZRSR2. Results: In cohort A 248 cases (31%) with TET2mut were identified. TET2del and a normal karyotype were more frequent in MDS with TET2mut as compared to those with TET2 wild-type (wt) (3% vs 1%, p=0.006; 89% vs 78%, p<0.001). SF3B1 and ASXL1 were frequently mutated in both TET2mut and TET2wt MDS (32% and 34%, 22% and 18%, respectively). In MDS with TET2mut compared to MDS with TET2wt the following genes were less frequently mutated: ATM (0.5% vs 3%, p=0.05), DNMT3A (9% vs 15%, p=0.02), ETV6 (0.5% vs 3%, p=0.03), IDH1 (0.5% vs 3%, p=0.02), IDH2 (1% vs 5%, p=0.002), TP53 (2% vs 7%, p=0.004), U2AF1 (4% vs 9%, p=0.04), while the following genes were more frequently mutated: CBL (6% vs 2%, p=0.01), EZH2 (8% vs 2%, p<0.001), SRSF2 (27% vs 12%, p<0.001), and ZRSR2 (15% vs 3%, p<0.001). Overall spliceosome genes were more frequently mutated in TET2mut than in TET2wt MDS (77% vs 56%, p<0.001). In the total cohort A neither TET2mut nor TET2del had an impact on overall survival (OS). In TET2mut MDS and TET2wt MDS SF3B1mut were associated with favorable outcome, while TP53mut were associated with shorter OS in both subsets (table 1). However in TET2mut MDS mutations in RUNX1 (p<0.0001), CBL (p=0.001), and U2AF1 (p=0.03) were independently associated with shorter OS, while in TET2wt MDS mutations in KRAS (p=0.03), EZH2 (p=0.02), NRAS (p=0.02), SRSF2 (p=0.007), IDH2 (p=0.05), and ASXL1 (p=0.01) were independently associated with shorter OS. In cohort B 40/77 (52%) MDS with TET2del also harbored a TET2mut. The 4q deletion encompassing the TET2 gene was < 10 MB in size and thus cytogenetically cryptic in 77% of cases with TET2mut, while the TET2 deletion was cryptic in only 24% of cases without TET2mut. A normal karyotype was present in 37 cases (48%), a complex karyotype in 29 (38%) and other abnormalities in 11 cases (14%). TET2mut were frequent in cases with a normal karyotype (68% vs aberrant karyotype: 32%, p<0.001) and were rare in cases with a complex karyotype (13%). Relating the mutation load of TET2mut to the proportion of cells with TET2del as determined by FISH revealed in 60% of cases that both TET2 alterations were present in the main clone, while in 23% of cases the TET2mut was present in a subclone only and in 17% the TET2del was observed in a subclone only. In the subset of patients with TET2del in a subclone only, 83% showed a normal karyotype and none a complex karyotype, while in the subset of cases with TET2mut in a subclone only, 43% showed a normal and 29% a complex karyotype. In the total cohort B the presence of a TET2mut in addition to the TET2del had no prognostic impact, while the presence of a complex karyotype was associated with shorter OS (RR: 8.0, p=0.004). Conclusions: 1) TET2 deletions are rare in TET2 mutated MDS (3%). 2) TET2 mutations are frequent in MDS with TET2 deletion (52%). 3) TET2 mutations are highly correlated to a normal karyotype and are rare in complex karyotype. 3) Neither TET2 mutations nor TET2 deletions have a prognostic impact in MDS. 4) In TET2 mutated MDS mutations in RUNX1, TP53, CBL, and U2AF1 have the strongest negative independent impact on OS, which in TET2 wild-type MDS is the case for mutations in TP53, KRAS, EZH2, NRAS, SRSF2, IDH2 and ASXL1. Table The relative risk of parameters significantly (p<0.05) associated with overall survival are depicted in TET2 mutated and TET2 wild-type MDS Table. The relative risk of parameters significantly (p<0.05) associated with overall survival are depicted in TET2 mutated and TET2 wild-type MDS Disclosures Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Stengel:MLL Munich Leukemia Laboratory: Employment. Meggendorfer:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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A Comprehensive Cytogenetic and Molecular Genetic Characterization of Patients with T-PLL Revealed Two Distinct Genetic Subgroups and JAK3 Mutations As an Important Prognostic Marker

Blood ◽

10.1182/blood.v124.21.1639.1639 ◽

2014 ◽

Vol 124 (21) ◽

pp. 1639-1639

Author(s):

Anna Stengel ◽

Wolfgang Kern ◽

Melanie Zenger ◽

Karolina Perglerová ◽

Susanne Schnittger ◽

...

Keyword(s):

T Cell ◽

Prognostic Marker ◽

Array Cgh ◽

Molecular Genetic ◽

Employment Equity ◽

Copy Number State ◽

Tp53 Mutations ◽

Genetic Abnormalities ◽

Equity Ownership

Abstract Background: T-cell prolymphocytic leukemia (T-PLL) is a rare, mature T-cell neoplasm with poor prognosis. Only few T-PLL cases have been analyzed with regard to cytogenetic and molecular genetic aberrations so far. Therefore, we performed a comprehensive characterization of patients with T-PLL, including the identification of potential correlations between the respective markers and their impact on prognosis. Methods: The cohort comprised 47 T-PLL cases (32 male, 15 female). Median age was 69.8 years (range: 32.7-86.6 years). Diagnosis of T-PLL was assigned by immunophenotyping and cytomorphology. All 47 patients were further investigated using (i) chromosome banding analysis (CBA), (ii) interphase FISH to determine the copy number state for TP53 and ATM and chromosomal rearrangements of TCRA/D and TCL1 and (iii) array CGH. Next-generation amplicon deep-sequencing was performed to analyze mutations in ATM,BCOR, TP53 (n=47, respectively); JAK1 (n=44) and JAK3 (n=45) were analyzed by Sanger sequencing. Clinical follow-up data was available for 43 patients. Results: In all 47 cases, chromosomal abnormalities and/or molecular mutations were detected. Combining CBA and FISH data, an inv(14)(q11q32)/t(14;14)(q11;q32) was observed in 37/47 (78.7%) cases, a t(X;14)(q27;q11) in 3 cases (6.4%) and an i(8)(q10) in 17/47 (36.2%) cases. ATM deletions were detected in 27/47 (57.5%), TP53 deletions in 11/47 (23.4%) patients. Array CGH analyses revealed additional gains and losses of specific chromosomal regions, mainly affecting 7q (deletions in region 7q34-7q36; n=16), 12p (deletions in 12p12-12p13; n=11) and 22q (deletions in 22q11-q12 with a concomitant gain of 22q12-q13; n=8). Regarding molecular analyses, the most frequently mutated gene was ATM (34/47; 72.3%). Mutations in TP53 were found in 7/47 (14.9%) and in BCOR in 4/47 (8.5%) patients. Mutations of JAK1 were found in 3/44 (6.8%), and of JAK3 in 8/45 (17.8%) cases. ATM and TP53 frequently carried a mutation of one allele and a deletion of the other: 23/34 (67.6%) cases with ATM mutation also showed an ATM deletion and in 5/7 (71.4%) cases with TP53 mutation also a TP53 deletion was detected. Regarding chromosomal aberrations, all cases with i(8)(q10) harbored a TCRA/D rearrangement and an ATM mutation, whereas TP53 mutations were not present in any case with i(8)(q10). ATM mutations were found to be correlated to TCRA/D rearrangements (33/40 TCRA/D+ cases, 82.5%; 1/7 TCRA/D- cases, 14.3%; p<0.001). In contrast, TP53 mutations were predominantly observed in patients without TCRA/D rearrangement (4/7 TCRA/D- cases, 57.1%; 3/40 TCRA/D+ cases, 7.5%; p=0.008). Additionally, all three JAK1 mutations were detected in cases with a TCRA/D rearrangement. When splitting the cohort into patients ≤60 years (n=13) and >60 years (n=34), JAK1 mutations (0/12 vs. 3/32) and mutations/deletions in the TP53 gene were detected exclusively in patients >60 years (TP53mut: 0/13 vs. 7/34; TP53del: 0/13 vs. 11/34). JAK3 mutations were also found predominantly in older patients (1/12; 8.3% vs. 7/33; 21.2%). Median overall survival (OS) was 27.4 months. No influence on OS was found for mutations and/or deletions of ATM, TP53, BCOR orJAK1 or aberrations of chromosomes 8 or 14. The age of patients was found to impact OS (median OS, ≤60 years: 29.0 months vs. >60 years: 15.9 months), although this was not significant (p=0.077). However, OS was found to be significantly shorter in patients with JAK3 mutation compared to patients without JAK3 mutation (median OS, 5.1 months vs. 29.1 months; p=0.009). Conclusions: Genetic abnormalities were revealed in all 47 cases with T-PLL. Two distinct genetic subgroups of T-PLL were identified: A large subset, comprising 81% of patients, showed abnormalities involving the TCRA/D locus activating the proto-oncogenes TCL1 (14q32) or MTCP1 (Xq28). This subgroup had higher frequencies of i(8)(q10) and of ATM mutations, while the second group was characterized by a higher frequency of TP53 mutations (figure). Further, JAK3 mutations were identified as an important prognostic marker, showing a significant negative impact on OS. Figure 1: Genetic abnormalities in T-PLL Figure 1:. Genetic abnormalities in T-PLL mut=mutation, del=deletion, TCRA/D=rearrangements involving TCRA/D, TCL1=rearrangements involving TCL1, MTCP1= rearrangements involving MTCP1 Disclosures Stengel: MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Zenger:MLL Munich Leukemia Laboratory: Employment. Perglerová:MLL2 s.r.o.: Employment. 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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TP53 Mutations Are Present In 15.7% Of ALL, Are Especially Frequent In ALL With MYC-Rearrangement and In ALL With Low Hypodiploid Chromosome Status and Are Associated With Poor Prognosis

Blood ◽

10.1182/blood.v122.21.827.827 ◽

2013 ◽

Vol 122 (21) ◽

pp. 827-827

Author(s):

Claudia Haferlach ◽

Sandra Weissmann ◽

Sabrina Kuznia ◽

Susanne Schnittger ◽

Wolfgang Kern ◽

...

Keyword(s):

Mutation Frequency ◽

Tp53 Mutation ◽

Normal Karyotype ◽

Prognostic Impact ◽

Complex Karyotype ◽

Mutation Load ◽

Employment Equity ◽

Tp53 Mutations ◽

Equity Ownership ◽

B Lineage

Abstract Background TP53 is the most frequently mutated gene in cancer. The prognostic impact of TP53 mutations has been demonstrated in CLL, AML, and MDS. However, data on the frequency and prognostic impact of TP53 mutations in ALL is scarce. Aims We aimed at determining the TP53 mutation frequency, the association with cytogenetic subgroups and age, as well as the impact on survival. Patients and Methods In total, a large cohort of 625 patients with ALL was analyzed for TP53 mutations by deep-sequencing allowing to simultaneously quantify the mutation load. In all patients chromosome banding analyses have been performed. In addition, in 341 patients the copy number state of TP53 was determined by FISH. Results The cohort comprised 353 male and 272 female patients, median age was 49.5 years (range: 0.1-91.4 years). The cohort included the following groups: normal karyotype (n=101; 16.2%), t(9;22)(q34;q11) (n=162; 25.9%), MLL-translocations (n=37; 5.9%), MYC-translocations (n=40; 6.4%), t(12;21)(p13;q22) (n=15; 2.4%), low hypodiploidy (<40 chromosomes) (n=24; 3.8%), high hyperdiploidy (51-68 chromosomes) (n=38; 6.1%), complex karyotype (n=69; 11.0%), other cytogenetic abnormalities (n=139; 22.2%). Detailed data on immunophenotyping was available for 408 patients (T-lineage: n=105; B-lineage: n=267, Burkitt: n=36). In the total cohort, the frequency of TP53 mutations was 15.7% (98/625). TP53 mutations were most frequent in ALL with low hypodiploidy (22/24; 91.7%) and MYC-translocated ALL (25/40; 62.5%) and also quite frequent in ALL with complex karyotype (16/69; 23.2%), ALL with normal karyotype (13/101; 17.4%), and in MLL-translocated ALL (6/37; 16.2%). TP53 mutations were rare in t(9;22)(q34;q11) (7/162; 4.3%), high hyperdiploidy (3/38; 6.1%), and other cytogenetic abnormalities (6/139; 4.3%) and absent in ALL with t(12;21)(p13;q22) (0/15; 0%). Furthermore, TP53 mutations were less frequent in T-lineage ALL (8/105; 7.6%) as compared to B-lineage and Burkitt ALL (41/267; 15.4% and 21/36; 58.3%). TP53 mutation frequency increased with age (TP53mut <60 years vs ≥ 60 years 10.8% (45/417) vs 25.5% (53/208), p<0.0001). 25/64 (39.1%) TP53 mutated patients with available TP53 deletion status showed a deletion of the second allele, while in 17/319 (5.3%) TP53wt patients with available TP53 deletion status a TP53 deletion was detected (p<0.001). 11/98 (11.2%) TP53 mutated patients showed two TP53 mutations. Median overall survival (OS) was significantly shorter in TP53mut vs TP53wt patients (18.8 months vs 75.5 months, p<0.0001). OS at 4 years in patients <60 years was 80.1% in TP53wt compared to 56.8% in TP53mut (p=0.012) and 59.3% vs 22.6% in patients ≥ 60 years (p<0.0001). Also within the cytogenetic categories MYC-translocated and complex karyotype TP53 mutations had a significant adverse impact on overall survival. Further, patients with either two TP53 mutations or one TP53 mutation and an accompanying TP53 deletion had a significantly shorter OS as compared to patients with only one altered TP53 allele (median OS 11.5 vs 63.1 months, p=0.009). In contrast, OS in patients with a TP53 deletion without a TP53 mutation did not differ from patients without TP53 alterations. In addition, the TP53 mutation load was investigated by next-generation sequencing and varied between 2% and 98% (median: 41%). Within the subset of patients with TP53 mutation, patients with a mutation load >20% showed a significantly shorter OS as compared to patients with a lower mutation load (median OS 11.5 months vs not reached, p=0.003). Interestingly, OS in patients with a TP53 mutation load ≤ 20% did not differ from TP53wt patients. In multivariate Cox regression analysis including parameters significantly associated with shorter OS in univariate analysis the following factors retained an independent adverse impact on OS: age (<60 years vs ≥ 60 years, HR=2.2; p=0.01), MLL-translocation (HR=2.8; p=0.03), and TP53mut >20% (HR: 3.1, p=0.01). Conclusions 1. TP53 is mutated in 15.7% of ALL with the highest frequency in ALL with low hypodiploidy (91.7%) and MYC-translocated ALL (62.5%). 2. The TP53 mutation frequency increases with age. 3. TP53 mutations are associated with short survival independent of age and specific cytogenetic alterations. 4. TP53 mutations had a significant impact on OS only if the mutation load was >20%. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Weissmann:MLL Munich Leukemia Laboratory: Employment. Kuznia:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Metabolic Flux in Both the Purine Mononucleotide and Histidine Biosynthetic Pathways Can Influence Synthesis of the Hydroxymethyl Pyrimidine Moiety of Thiamine in Salmonella enterica

Journal of Bacteriology ◽

10.1128/jb.184.22.6130-6137.2002 ◽

2002 ◽

Vol 184 (22) ◽

pp. 6130-6137 ◽

Cited By ~ 26

Author(s):

Shara Allen ◽

Julie L. Zilles ◽

Diana M. Downs

Keyword(s):

Metabolic Flux ◽

Genetic Characterization ◽

Molecular Genetic ◽

Thiamine Pyrophosphate ◽

Wild Type ◽

Regulatory Pathway ◽

Informational Suppressors ◽

Pyrimidine Moiety ◽

Molecular Genetic Characterization

ABSTRACT Together, the biosyntheses of histidine, purines, and thiamine pyrophosphate (TPP) contain examples of convergent, divergent, and regulatory pathway integration. Mutations in two purine biosynthetic genes (purI and purH) affect TPP biosynthesis due to flux through the purine and histidine pathways. The molecular genetic characterization of purI mutants and their respective pseudorevertants resulted in the conclusion that <1% of the wild-type activity of the PurI enzyme was sufficient for thiamine but not for purine synthesis. The respective pseudorevertants were found to be informational suppressors. In addition, it was shown that accumulation of the purine intermediate aminoimidazole carboxamide ribotide inhibits thiamine synthesis, specifically affecting the conversion of aminoimidazole ribotide to hydroxymethyl pyrimidine.

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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 ◽

10.1182/blood.v116.21.953.953 ◽

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.

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Landmark Analyses of DNMT3A Mutations in Hematological Malignancies

Blood ◽

10.1182/blood.v118.21.407.407 ◽

2011 ◽

Vol 118 (21) ◽

pp. 407-407

Author(s):

Vera Grossmann ◽

Alexander Kohlmann ◽

Claudia Haferlach ◽

Tamara Alpermann ◽

Melanie Wild ◽

...

Keyword(s):

Overall Survival ◽

Mutation Rate ◽

Mutation Frequency ◽

Cpg Methylation ◽

Homozygous Mutation ◽

Wild Type ◽

Employment Equity ◽

Acute Leukemias ◽

Equity Ownership

Abstract Abstract 407 CpG methylation is an epigenetic modification that is important for cellular development. The DNMT3A gene, located on chromosome 2p23.3, encodes for a DNA methyltransferase and plays a central role in de novo CpG methylation. Recently, DNMT3A has been reported to be mutated in 22% of AML and 8% of MDS (Ley et al., N Engl J Med, 2010; Walter et al., Leukemia, 2011). Further, DNMT3A mutations were observed to be associated with a short overall survival in both diseases, respectively. In order to determine the role of DNMT3A mutations in leukemia we investigated two different entities by next-generation sequencing: 145 AML patients and 83 cases harboring a T-cell acute lymphoblastic leukemia (T-ALL). We applied an amplicon based deep-sequencing assay (454 Life Sciences, Branford, CT) in combination with the 48.48 Access Array technology (Fluidigm, South San Francisco, CA). The peripheral blood or bone marrow samples were obtained from untreated patients. The AML cohort was restricted to cases with normal karyotype (CN-AML). 87/145 (60%) cases were specifically selected to be wild-type for NPM1, FLT3-ITD, CEBPA, and MLL-PTD, whereas 58/145 (40%) samples were mutated in NPM1 (n=33) or double-mutated in NPM1 and FLT3-ITD (n=25). In our cohort of AML cases without mutations in NPM1, FLT3-ITD, CEBPA, and MLL-PTD, we observed a DNMT3A mutation frequency of 17.2% (15/87 cases). The DNMT3A mutation rate in the NPM1 mutated/FLT3 wild-type cases (16/33, 48.5%, P=0.001) and NPM1/FLT3-ITD mutated cases (19/25, 76%, P<0.001) was significantly higher, confirming the association of DNMT3A mutations with NPM1 and FLT3-ITD mutations that had been reported previously (Ley et al.). Interestingly, also in the cohort of T-ALL we detected patients that carried a DNMT3A mutation (16/83, 19.3%), which is very similar to the mutation frequency in AML, and has not been described yet. To further address the biology of DNMT3A mutations in acute leukemias we combined the AML and T-ALL cohorts and identified in total 31 distinct missense mutations in 65 patients (49 AML, 16 T-ALL). Most frequently, amino acid R882 located in exon 23 was mutated (n=29 cases). In addition, we identified 7 frame-shift alterations, 5 nonsense and 2 splice-site mutations. Moreover, 9 of the 65 mutated cases had two independent mutations. Focusing on AML, only three (6.1%) of the 49 DNMT3A-mutated cases were observed to harbor two different mutations concomitantly. In contrast, in the cohort of T-ALL we detected two different mutations in 6/16 (37.5%, P=0.003) cases. Further, in the cohort of AML, no homozygous mutation was detected, however, in the T-ALL group, two cases harbored a homozygous mutation. Therefore, only 3/49 AML (6.1%) cases, but 8/16 T-ALL (50%) cases showed biallelic mutation status (P<0.001). With respect to overall survival, no association was seen in the complete cohort of CN-AML cases (n=145). After limiting this cohort to the cases without mutations in NPM1, FLT3-ITD, CEBPA and MLL-PTD (n=87), an inferior survival was observed for DNMT3A-mutated patients as compared to DNMT3A wild-type patients (n=15 vs. n=72; alive at 2 years: 27.9% vs. 56.6%; P=0.048). Remarkably, also in the cohort of T-ALL a worse survival for patients with DNMT3A mutations was seen which has not been reported thus far (n=13 vs. n=64; alive at 1 years: 28.6% vs. 80.9%; P=0.001). Subsequently, we were interested whether gain-of-function mutations of the DNMT3A gene were associated with trisomy 2 and acquired uniparental disomy (aUPDs) of the short arm of chromosome 2 where DNMT3A is located. As such, we investigated 9 cases harboring a trisomy 2 (AML n=4, MDS n=4, and CMML n=1) and one MDS patient harboring an aUPD 2p, as confirmed by SNP microarray analyses (SNP Array 6.0, Affymetrix, Santa Clara, CA). Not all, but 3/9 cases with trisomy 2 harbored a DNMT3A mutation (one AML, MDS, and CMML case each), suggesting that duplication of DNMT3A mutations can enhance the effect of the mutation. Moreover, the single case with aUPD 2p also showed a mutation, further suggesting that LOH leading to loss of the wild-type DNMT3A may be another mechanism of disease leading to progression of leukemia. In conclusion, we here report on a high mutation rate of DNMT3A in both AML and T-ALL and independently confirmed an inferior overall survival in these two entities, respectively. This indicates a significant role of DNMT3A alterations in myeloid as well as in lymphoid neoplasms. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Alpermann:MLL Munich Leukemia Laboratory: Employment. Wild:MLL Munich Leukemia Laboratory: Employment. Weissmann:MLL Munich Leukemia Laboratory: Employment. Eder:MLL Munich Leukemia Laboratory: Employment. Dicker: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.

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Gene Mutations Identified in Chemorefractory Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v126.23.3838.3838 ◽

2015 ◽

Vol 126 (23) ◽

pp. 3838-3838

Author(s):

Anthony Palmer ◽

Brian Parkin ◽

Hidde Posthuma ◽

Shin Mineishi ◽

John M. Magenau ◽

...

Keyword(s):

Gene Mutations ◽

Refractory Disease ◽

Wild Type ◽

Discovery Cohort ◽

Protein Coding ◽

Tp53 Mutations ◽

Whole Exome ◽

Equity Ownership ◽

Secondary Refractory ◽

Refractory Aml

Abstract Introduction: Acute myeloid leukemia (AML) is a genetically heterogeneous disease. Recently, multiple recurrently mutated genes have been identified in AML and implicated in various mechanisms of leukemogenesis. However, knowledge regarding the association of gene mutations with primary or secondary resistance to chemotherapy is incomplete. Methods: We analyzed a discovery cohort of 45 patients with chemorefractory AML that were enrolled in a phase 2 clinical trial of a novel conditioning regimen prior to allogeneic stem cell transplant for patients with non-remission AML. DNA was extracted from FACS-purified leukemic cells procured from patients after failure to achieve complete remission (CR) after ≥2 cycles of induction chemotherapy after initial diagnosis ("primary refractory", N=22) or after rapid relapse (<6 months) or failure to achieve CR after ≥1 cycle of induction chemotherapy after relapse ("secondary refractory", N=23). Since TP53 mutations have been previously associated with refractory disease, we selected 29 TP53 wild-type cases from the discovery cohort and performed whole exome sequencing (WES) with a mean read depth of 72X (range 30-140). All somatically acquired gene variants identified by WES in protein-coding genes were verified by Sanger sequencing. In addition, we performed Sanger re-sequencing of 11 recurrently mutated genes in AML (TP53, RUNX1, DNMT3A, TET2, FLT3, NPM1, IDH1, IDH2, ASXL1, NRAS and KRAS) in all 45 cases. Given lack of published WES data in refractory AML, we then compared these mutation frequencies to a cohort of 151 AML patients enrolled consecutively at one center (the "university cohort") with known responses to chemotherapy or The Cancer Genome Atlas (TCGA) data which comprises de novo AML only. Results: WES of 29 TP53 wild-type refractory AML cases revealed a total of 351 confirmed somatic mutations with a median of 13 protein-coding mutations per case (range 5-22). Genes mutated in 7% (2 of 29 cases), and excluding the 11 known recurrently mutated genes listed above, that were not previously described in AML (COSMIC review) included ADAM23, CPNE7, and SIX5. We also identified mutations in NOMO3 and OAS2 in 7% (2 of 29 cases), which have been previously described in AML but at lower frequencies (1.7% [6 of 347; COSMIC] and 0.2% [1 of 347] respectively) based on review of the literature. The genes SRSF2, NOMO3 and OAS2, which were all identified in 7% (2 of 29 cases) in our discovery cohort, had no reported mutations found in the TCGA (p=0.02). Additional genes, which were found in our discovery cohort in 7% (2 of 29 cases) respectively, and were also found in the TCGA, include BCOR, FOXP1, FRYL, PHF6, STAG2, PTPN11 and SETD2. Mutational profiling of the 11 recurrently mutated genes in AML revealed a striking paucity of NPM1 mutations in primary refractory AML (range 0% [discovery cohort] - 3% [university cohort]) compared with chemosensitive AML (31% [university cohort]; p<0.001). TP53 mutations, however, were enriched in primary refractory AML (range 23% [discovery cohort] - 38% [university cohort]) compared with chemosensitive AML (4% [university cohort]; p<0.001). Of note, while FLT3 -ITD mutations were infrequently observed in primary refractory AML (range 0% [discovery cohort] - 14% [university cohort]) compared to chemosensitive AML (27% [university cohort]; p<0.01), they were highly enriched in secondary refractory AML (61% [discovery cohort] - 30% [university cohort]; p=0.03). Conclusions: 1) Whole exome sequencing of 29 TP53 wild-type refractory AML revealed recurrent mutations in ADAM23, CPNE7, NOMO3, OAS2 and SIX5. The function and prevalence of these gene mutations are not well-characterized in AML, including refractory AML and should be determined in a larger cohort of patients; 2) TP53 mutations were significantly enriched in primary refractory disease; 3) Conversely, FLT3 -ITD mutations were significantly enriched in secondary but not primary refractory disease, suggesting the frequent emergence of a chemorefractory FLT3-ITD mutated clone following treatment with conventional chemotherapy; and, 4) NPM1 mutations were significantly under-represented in primary refractory AML. While larger sequencing studies of refractory AML cases are needed, these data do not support gene mutations other than in TP53 as frequent causes of primary refractoriness to chemotherapy in AML. Disclosures Malek: Gilead Sciences: Equity Ownership; Abbvie: Equity Ownership; Janssen Pharmaceuticals: Research Funding.

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Characterization of plasminogen variants in healthy subjects and plasminogen mutants in patients with inherited plasminogen deficiency by isoelectric focusing gel electrophoresis

Thrombosis and Haemostasis ◽

10.1160/th04-01-0041 ◽

2004 ◽

Vol 92 (08) ◽

pp. 352-357 ◽

Cited By ~ 6

Author(s):

Katrin Tefs ◽

Maria Georgieva ◽

Stefan Seregard ◽

Campbell Tait ◽

Lori Luchtman-Jones ◽

...

Keyword(s):

Isoelectric Focusing ◽

Gel Electrophoresis ◽

Healthy Subjects ◽

Molecular Genetic ◽

Gene Mutations ◽

Molecular Genetic Analysis ◽

Compound Heterozygous ◽

Wild Type ◽

Ligneous Conjunctivitis

SummaryPlasmin(ogen) plays an important role in fibrinolysis and wound healing. Severe hypoplasminogenemia has recently been linked to ligneous conjunctivitis. Plasminogen (plg) is known as a polymorphic protein and most of these variants have been identified using isoelectric focusing (IEF) gel electrophoresis. Here, we studied common plg variants from healthy subjects and plg mutants from three patients with hypoplasminogenemia and three subjects with dysplasminogenemia by molecular genetic analysis and IEF. Analysis of 24 healthy subjects showed that subjects with the most common IEF plg phenotype A (n = 12) were homozygous for aspartate at position 453 (453D), while both subjects with IEF plg phenotype B were homozygous for asparagine at this position (453N). Subjects with IEF plg phenotype AB (n = 10) were compound-heterozygous for 453D/453N. Three patients with severe hypoplasminogenemia and different plg gene mutations exhibited characteristic “abnormal” IEF band patterns when compared with IEF plg phenotypes A and B. In all heterozygous family members the observed IEF plg phenotype was derived from the wild type plg molecule only, probably due to low concentration of the mutant plg molecule in plasma. In contrast, in three unrelated subjects with heterozygous dysplasminogenemia an equal “mixture” of wild type and mutant plg was found by IEF analysis. In conclusion, plg phenotyping by IEF in combination with molecular analysis of the plg gene seems to be a useful method for characterization of plg variants and mutants.

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Mutations of the TP53 Gene Occur in 13.4% of Acute Myeloid Leukemia and Are Strongly Associated with a Complex Aberrant Karyotype.

Blood ◽

10.1182/blood.v108.11.1913.1913 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1913-1913

Author(s):

Claudia Schoch ◽

Frank Dicker ◽

Hannes Herholz ◽

Susanne Schnittger ◽

Wolfgang Kern ◽

...

Keyword(s):

Tp53 Mutation ◽

Fusion Gene ◽

Direct Sequencing ◽

Mutation Screening ◽

Molecular Genetic ◽

Treatment Strategies ◽

Normal Karyotype ◽

Tp53 Gene ◽

Trisomy 8 ◽

Tp53 Mutations

Abstract The TP53 gene is the most frequently mutated gene in human tumors identified so far. In a prior study we demonstrated that 78% of AML with complex aberrant karyotype show a mutation of the TP53 gene. The aim of this study was to determine the frequency of TP53 mutations in an unselected cohort of AML and to analyze the relation to cytogenetic and molecular genetic aberrations. In total 149 AML cases were examined by chromosome banding analysis and screened for FLT3-length mutations (FLT3-LM), MLL partial tandem duplication (MLL-PTD), NPM1 mutations, and TP53 mutations. The cohort included cases with t(8;21) (n=10), t(15;17) (n=6), inv(16) (n=4), 11q23/MLL-rearrangement (n=6), trisomy 8 sole (n=13), AML with normal karyotype (n=46), AML with complex aberrant karyotype defined as showing 3 and more clonal abnormalities but no balanced rearrangement leading to a leukemia specific fusion gene (n=26), and AML with other abnormalities (n=38). FLT3-LM were observed in 21, MLL-PTD in 4, and NPM1-Mutations in 26 cases. TP53 mutation screening of exons 3–9 was performed by denaturing high performance liquid chromatography (DHPLC). All mutations detected were verified by direct sequencing. Overall, TP53 mutations were detected in 20 of the 149 cases (13.4%). Within this cohort of TP53 mutated cases, coincidences of FLT3-LM and MLL-PTD, respectively, with TP53 mutation were detected in one case each. A complex aberrant karyotype was present in 17 of 20 cases (85%) with TP53 mutation. The remaining 3 cases with TP53 mutation showed a normal karyotype, a trisomy 8, and t(8;21) as the sole abnormality, respectively. Therefore, we confirmed a high incidence of TP53 mutations in AML with complex aberrant karyotype (17/26, 65.4%). On the other hand TP53 mutations are very rare in AML without a complex aberrant karyotype (3/123, 2.4%). Furthermore, we divided AML with complex aberrant karyotype into two subgroups:AML with “typical” complex aberrant karyotype showing a deletion of at least one of the following regions: 5q31, 7q31, 17p13 (definition according to Schoch et al. GCC, 2005) andAML with “untypical” complex aberrant karyotype comprizing all others. Interestingly, the frequency of TP53 mutations within the “typical” complex aberrant karyotype group was 75% (15/20) while in the “untypical” group it was 33% (2/6) (p=0.138). In conclusion, the overall incidence of TP53 mutations is low in AML. TP53 mutations are highly associated with AML and complex aberrant karyotype and occur very infrequently in all other cytogenetic subgroups (p<0.001). They occur frequently in particular in the subgroup showing a typical pattern of chromosomal deletions (5q, 7q, 17p). TP53 mutations might explain in part the chemoresistance of AML with complex aberrant karyotype. In addition to cytogenetics a rapid diagnostic screening for TP53 mutations could be a valuable tool to identify a subgroup of AML with poor prognosis. This would allow the early assignment of patients to alternative treatment strategies using also options targeting the TP53 pathway.

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The TP53 Codon72 Polymorphism Is Associated with TP53 Mutations in Chronic Lymphocytic Leukemia

Blood ◽

10.1182/blood.v118.21.1783.1783 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1783-1783 ◽

Cited By ~ 1

Author(s):

Vera Grossmann ◽

Valentina Artusi ◽

Susanne Schnittger ◽

Frank Dicker ◽

Sabine Jeromin ◽

...

Keyword(s):

Chronic Lymphocytic Leukemia ◽

Mutation Rate ◽

Tp53 Mutation ◽

Genome Project ◽

Lymphocytic Leukemia ◽

Wild Type ◽

Employment Equity ◽

Tp53 Mutations ◽

Equity Ownership ◽

Exon 4

Abstract Abstract 1783 TP53 is one of the most important cell-cycle regulator genes and its tumor suppressor activity is fundamental in cellular responses. Mutations in TP53 are known to influence clinical outcome in diverse diseases. In particular, a relationship between TP53 mutations and a poor prognosis has been established in chronic lymphocytic leukemia (CLL), which is one of the most commonly diagnosed lymphoid malignancies in Western countries. Thus far, it has been demonstrated that TP53 mutations are associated with codon72 polymorphism in different diseases e.g. breast cancer, lung cancer, head and neck squamous cell carcinoma, and that this variant could determine cancer susceptibility. In this study, we investigated the overall TP53 mutation rate in 511 CLL and focused on the codon72 polymorphism (rs1042522) in exon 4 (transcript-ID: ENST00000269305). We initially examined the published available 1000 Genome Project results of the European cohort: from a total of 283 genomes analyzed, 137 showed an ARG/ARG genotype (48%), 124 an ARG/PRO genotype (43%) and 22 a PRO/PRO genotype (7.7%). Secondly, in order to determine a potential association between this polymorphic variant and mutations in the TP53 gene, we investigated 511 thoroughly characterized patients with CLL, all diagnosed by immunophenotyping in our laboratory. For molecular analyses, all cases were analyzed for TP53 mutations (exon 4 to exon 11) either by DHPLC and subsequent Sanger sequencing (n=210/511), or using a sensitive next-generation amplicon deep-sequencing assay (n=301/511) (454 Life Sciences, Branford, CT). We observed the occurrence of the three distinct genotypes (ARG/ARG, ARG/PRO, PRO/PRO) of codon72 in the CLL cohort and detected ARG/ARG as the most common genotype (63%), followed by ARG/PRO (31.7%), and PRO/PRO (5.3%); very similar to the distribution of the codon72 polymorphism in the 1000 Genome Project data. Moreover, mutations in TP53 were detected in 63/511 patients resulting in an overall mutation rate of 12%, which reflects the expected mutation rate in this disease. Importantly, as already demonstrated in other malignancies, we here present that also in CLL patients harboring a PRO/PRO genotype a significantly higher frequency of TP53 mutations (9/27, 33%) was observed compared to ARG/ARG (41/321, 13%, P=.037) and ARG/PRO (13/163, 8%, P=.012). With respect to the clinical outcome we confirmed a generally poor survival for the TP53 mutated cases as compared to TP53 wild-type patients (n=23 vs. 189 with clinical data available, alive at 7 years: 29.6% vs. 88.1%; P<.001). Moreover, the impact of the three distinct genotypes on outcome was analyzed. However, no correlation was detectable, neither in the cohort of TP53 mutated cases (P=.225) nor in the TP53 wild-type patients (P=.190). In summary, we demonstrated a significant association between the codon72 allelic variant and TP53 mutation rate in our CLL cohort. Patients with a PRO/PRO genotype showed a significantly higher frequency of TP53 mutations than all other genotypes. However, no prognostic impact of codon72 allelic variant was observed, neither in the TP53 wild-type nor in the TP53 mutated cohort. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Artusi:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Dicker:MLL Munich Leukemia Laboratory: Employment. Jeromin:MLL Munich Leukemia Laboratory: Employment. Boeck:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment.

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