Paternally inherited WT1
 mutation plus uniparental disomy of 11p may be an essential mechanism for development of WT1
-mutated familial Wilms tumor

Abstract Abstract 3075 Poster Board III-12 The Wilms' tumor 1 (WT1) gene, located at chromosome band 11p13, encodes a transcriptional regulator involved in normal hematopoietic development. WT1 mutations have been identified in approximately 10 % of acute myeloid leukemia (AML), where it has recently been found to predict poor outcome, but also in T-cell acute lymphoblastic leukemias (T-ALL). Our aim was to evaluate the frequency, the main associated features and the prognostic significance of WT1 mutations in a cohort of pediatric patients with T-ALL treated according to EORTC-CLG trials. A total of 146 children, aged 7 months to 17 years, with newly diagnosed T-ALL were included in this study. Patients were treated according to 2 consecutive EORTC trials: 58 881 and 58 951. Immunophenotypic subtypes were classified according to the EGIL. Standard karyotype as well as molecular screening of HOX11/TLX1, HOX11L2/TLX3 and HOXA10 overexpression, SIL-TAL, NUP214-ABL, CALM-AF10 fusions were performed at diagnosis. WT1 transcript level was quantified by real-time PCR (RQ-PCR). Mutations of NOTCH1 exons 26, 27, 34, FBXW7 exons 9, 10, and WT1 exon 7, 9 were screened by direct sequencing. At least one WT1 mutation was found at diagnosis in 15 out of 146 (10%) T-ALL. WT1 mutations were predominantly exon 7 frameshift mutations (14/15 cases), consisting of small duplications, deletions or combined insertions/deletions, and were predicted to result in the production of a truncated protein missing the normal zinc finger domain. The remaining mutated patient harbored a somatically acquired missense mutation in exon 9 (C388Y), previously described in Denys-Drash syndrome. Only 4 out of 15 (27%) patients had 2 WT1 mutations and all WT1 mutations identified showed retention of the wild-type allele. Clonal evolution was investigated by analysis of 12 diagnostic-relapse pairs. Identical WT1 mutation was found at relapse in 3/4 mutated patients whereas 1/4 patients acquired an additional WT1 exon 7 mutation at relapse. One of the 8 patients with WT1 wild-type T-ALL at diagnosis acquired a WT1 exon 7 mutation at relapse. WT1 mutated and wild-type patients did not significantly differ in terms of age, gender, white blood cell count, or mediastinal involvement. Interestingly, WT1 mutated patients had significantly higher WT1 mRNA expression levels (median: 84% [25-837] for WT1 mutants vs 17% [0.007-657] for WT1 wild-type cases, p=0.005). This is in line with the trend for earlier developmental stage arrest observed in our WT1 mutated T-ALL as compared with WT1 wild-type T-ALL. Indeed, WT1 is preferentially expressed in immature hematopoietic progenitors and down-regulated in more differentiated cells. No association was found between the presence of WT1 mutations and NOTCH1 activating lesions. WT1 mutation was associated with HOX genes deregulation. HOX11 or HOX11L2 were overexpressed in 10/15 (67%) WT1 mutated ALL versus 29/123 (24%) WT1 wild-type ALL (p=0.001). In addition, HOXA overexpression and MLL-AF6 were found in one WT1 mutated T-ALL each. Overall, HOX deregulation was demonstrated in 12/15 (80%) WT1 mutated ALL at diagnosis and was also found in the T-ALL that acquired WT1 mutation at relapse. Despite being subclonal lesions strongly associated with HOX11 and HOX11L2 overexpression in T-ALL, WT1 mutations and NUP214-ABL fusion were found independent. A possible impact of WT1 mutation on outcome was investigated. The incidence of very high risk features was similar for patients with WT1 mutated and wild-type T-ALL. No significant differences were found between the WT1 mutated and wild-type group regarding 5-year event free survival (71.6% vs 74.1%; Wald test stratified for protocol: p=0.8) and overall survival (81.8% vs 81.3%; p=0.9). Notably, HOX112 overexpression, which is found in half of WT1 mutated T-ALL, has no pejorative impact either on outcome in EORTC trials. In conclusion, our study confirms that the type and incidence of WT1 mutations are very similar in pediatric T-ALL and AML, although the frequency of bi-allelic alterations may be lower in T-ALL. However, in contrast with AML, no pejorative outcome was associated with WT1 mutation. Moreover, we found that WT1 mutations are highly associated with direct or indirect aberrant HOX genes expression. Disclosures No relevant conflicts of interest to declare.

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Frequency and Heritability of WT1 Mutations in Nonsyndromic Wilms' Tumor Patients: A UK Children’s Cancer Study Group Study

Journal of Clinical Oncology ◽

10.1200/jco.2004.02.136 ◽

2004 ◽

Vol 22 (20) ◽

pp. 4140-4146 ◽

Cited By ~ 71

Author(s):

Suzanne E. Little ◽

Sandra P. Hanks ◽

Linda King-Underwood ◽

Chris Jones ◽

Elizabeth A. Rapley ◽

...

Keyword(s):

De Novo ◽

Age Of Onset ◽

Wilms Tumor ◽

Low Frequency ◽

Heteroduplex Analysis ◽

Study Group ◽

Histologic Subtype ◽

Cancer Study ◽

Cancer Study Group ◽

Wt1 Mutation

Purpose Constitutional WT1 mutations in patients with Wilms' tumor (WT) have specifically been associated with genitourinary abnormalities, such as cryptorchidism and hypospadias. We sought to ascertain the frequency and heritability of constitutional WT1 mutations in nonsyndromic WT patients. Patients and Methods Constitutional DNA from 282 patients treated at seven United Kingdom Children's Cancer Study Group centers was screened for WT1 mutations using heteroduplex analysis. Bidirectional sequencing was used to confirm the mutation and to analyze the corresponding parental DNA samples. Results Five different constitutional WT1 mutations were identified in six children. Mutations in four patients were confirmed to be de novo, and all five mutations are predicted to produce truncated protein. The WT1 mutation group had a young median age at diagnosis of 13.8 months, compared with 34.9 months in the group in whom no WT1 mutations were found; four were female and two were male; and all tumors were of favorable histology. The three tumors with known histologic subtype were stromal-predominant. Contrary to expectation, four of six mutations occurred in children with unilateral tumors without any associated genitourinary abnormality. Conclusion Constitutional WT1 mutations occur with a low frequency (2.1%; 95% CI, 0.8% to 4.6%) in nonsyndromic WT patients. Most mutations occurred in children with unilateral WT without associated genitourinary abnormalities, creating difficulties in identifying individuals with germline mutations on phenotype alone. Two factors that may indicate that an individual is carrying a germline WT1 mutation are an early age of onset and stromal-predominant histology of the WT.

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Possible acquired uniparental disomy 11 in a case of refractory Wilms tumor

Cancer Genetics and Cytogenetics ◽

10.1016/0165-4608(91)90441-v ◽

1991 ◽

Vol 56 (1) ◽

pp. 133

Author(s):

L McGavran ◽

A Taylor ◽

M Sage ◽

J Robinson ◽

D Snead ◽

...

Keyword(s):

Wilms Tumor ◽

Uniparental Disomy

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Germline Wilms tumor suppressor gene (WT1) mutation leading to isolated genital malformation without Wilms tumor or nephropathy

The Journal of Pediatrics ◽

10.1067/mpd.2001.112512 ◽

2001 ◽

Vol 138 (3) ◽

pp. 421-424 ◽

Cited By ~ 23

Author(s):

Birgit Köhler ◽

Valerié Schumacher ◽

Dagmar l’Allemand ◽

Brigitte Royer-Pokora ◽

Annette Grüters

Keyword(s):

Tumor Suppressor ◽

Tumor Suppressor Gene ◽

Wilms Tumor ◽

Suppressor Gene ◽

Genital Malformation ◽

Wt1 Mutation

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Mutation and Single-Nucleotide Polymorphism (rs16754) in Wilms Tumor-1 Gene Are Independent Prognostic Factors in Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v114.22.995.995 ◽

2009 ◽

Vol 114 (22) ◽

pp. 995-995 ◽

Cited By ~ 1

Author(s):

Wanlong Ma ◽

Hagop Kantarjian ◽

XI Zhang ◽

Xiuqiang Wang ◽

Zhong Zhang ◽

...

Keyword(s):

Bone Marrow ◽

Single Nucleotide Polymorphism ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Wilms Tumor ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Wilms Tumor 1 ◽

Wt1 Mutation ◽

Acute Myeloid

Abstract Abstract 995 Poster Board I-17 Several reports have suggested that mutations in the Wilms tumor 1 gene (WT1) represent an adverse prognostic factor in acute myeloid leukemia (AML). Here we examined the associations of WT1 mutations in exons 7 and 9 and the silent R301 single-nucleotide polymorphism (SNP) in exon 7 (A903G; NCBI dbSNP reference ID: rs16754) with outcome in AML patients treated at a single institution. Peripheral blood plasma and bone marrow samples from 174 newly diagnosed AML patients were tested for WT1 mutations in exons 7 and 9 by sequencing and fragment-length analysis for the detection of small deletions/insertions. Sequencing provided information on the specific genotype of the rs16754 SNP. The findings were correlated with outcome and other laboratory findings. WT1 mutation was detected in 7 of 50 (14%) AML patients <50 years of age and in 5 of 124 (4%) patients >50. The silent R301 SNP was detected at frequencies of 4% for GG, 26% for GA, and 70% for AA genotypes, but there was no difference with age. A similar SNP genotype distribution was detected in normal control subjects. WT1 mutations were associated with higher white cell count (P=0.01) and higher percentage of blasts in bone marrow (P=0.03) and peripheral blood (P=0.009). In addition, WT1 mutation was significantly associated with FLT3 mutation (P=0.002) but not NPM1 mutation (P=0.8). WT1 mutation was also significantly associated with shorter survival (P=0.025), event-free survival (P=0.002), and complete remission duration (P=0.002) in patients <50 years of age, but not in older patients. The association with shorter survival persisted when only patients with intermediate cytogenetics were considered (P=0.03). There was no correlation between WT1 mutation and response to therapy. The most striking correlation was between the presence of the GG genotype at R301 and longer survival, irrespective of age (see survival chart below). There was no difference in survival between the AA and GA groups. To the best of our knowledge, this is the first report describing correlation between survival duration and an SNP in the WT1 gene. While we confirm that the presence of WT1 mutation is associated with poor outcome in young AML patients, our data suggest that there is no clinical value in testing patients older than 50 for WT1 mutation, but that there may be value in testing adult patients of all age groups for the SNP polymorphism at R301 Disclosures: No relevant conflicts of interest to declare.

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Constitutional WT1 mutations in Wilms' tumor patients.

Journal of Clinical Oncology ◽

10.1200/jco.1998.16.11.3634 ◽

1998 ◽

Vol 16 (11) ◽

pp. 3634-3640 ◽

Cited By ~ 40

Author(s):

L Diller ◽

M Ghahremani ◽

J Morgan ◽

P Grundy ◽

C Reeves ◽

...

Keyword(s):

Wilms Tumor ◽

Case Reports ◽

Clinical Manifestations ◽

Case Series ◽

Peripheral Blood Lymphocytes ◽

Wt1 Gene ◽

Increased Risk ◽

History Of ◽

Genitourinary Anomalies ◽

Wt1 Mutation

PURPOSE Patients with Wilms' tumors (WT) who carry constitutional mutations in the WT1 gene have been described in case reports and small case series. We sought to determine the frequency of constitutional WT1 mutations in a larger cohort, and to identify clinical manifestations associated with the risk for carrying a WT1 mutation. METHODS We collected clinical data and blood samples from 201 patients with a history of WT. Southern blot analysis, single-strand conformation polymorphism (SSCP) analysis, and direct DNA sequencing were performed on DNA isolated from peripheral-blood lymphocytes from each patient. Odds ratios (ORs) for the carriage of a germline mutation of the WT1 gene were calculated for patients who had specific clinical risk factors compared with those who did not. RESULTS Of 201 patients with WT in the cohort, eight patients were carriers of mutations in the WT1 gene. Six of the eight mutations were protein-truncating nonsense mutations. None of 56 patients with isolated unilateral WT was a carrier. The OR of carrying a WT1 mutation was elevated for patients with genitourinary anomalies (OR19.3; P < .002). Seven of 28 boys with WT with cryptorchidism carried WT1 mutations. No increased risk was observed for patients with nephrogenic rests, bilateral tumors, history of secondary cancers, or family history of WT. CONCLUSION Germline WT1 mutations in patients with WT are associated with genitourinary anomalies, especially cryptorchidism and/or hypospadias. Patients with WT and no genitourinary anomalies are at low risk for carrying a WT1 mutation. Constitutional WT1 mutations that encode truncated WT1 proteins may predispose to the development of cryptorchidism, hypospadias, and WTs.

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Wilm’s Tumour 1 (WT1) Mutations Are Associated with FLT3-ITD Mutation and Poor Prognosis in Normal Karyotype AML.

Blood ◽

10.1182/blood.v108.11.2302.2302 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2302-2302

Author(s):

Jude Fitzgibbon ◽

Karin Summers ◽

Ioannis Kakkas ◽

Jane Stevens ◽

Matthew Smith ◽

...

Keyword(s):

Overall Survival ◽

Direct Sequencing ◽

Mutation Screening ◽

Uniparental Disomy ◽

Normal Karyotype ◽

Positive Association ◽

Poor Overall Survival ◽

Significant Positive Association ◽

Mutation Profile ◽

Wt1 Mutation

Abstract Our group has previously shown an association between acquired uniparental disomy 11p and homozygous gene mutation of Wilm’s tumour 1 (WT1) in a patient with normal karyotype acute myeloid leukemia (AML). Based on this observation the incidence of WT1 mutation was investigated in a cohort of normal karyotype AMLs. Mutation screening was performed on 70 patients (median age 55 years, range 19–78 years) by a PCR-direct sequencing approach using intronic primers flanking exons 2–10 of WT1. Mutation status was inferred from the resultant traces and confirmed by use of TOPO TA cloning and sequence analysis of the corresponding mutated clones. Mutations were detected in 7/70 (10%) patients; these typically resulted in insertion of 1–16 bp that led to the disruption of the DNA binding domain of the protein. The mutation profile of FLT3-ITD, NPM and CEBPA was also examined in this cohort of patients to compare the additional mutational events present in WT1 mutated and non-mutated cases. A significant positive association was observed between WT1 and FLT3-ITD mutation with 6/7 WT1 mutated cases having a FLT3-ITD compared to 20/63 non mutated cases (p=0.01). There was no association between mutations in WT1 and either of the good prognostic mutational markers, CEBPA and NPM. All 6 patients with both WT1 and FLT3 mutations were refractory to intensive induction chemotherapy with WT1 mutation showing a trend towards a worse overall survival when compared with the non-mutated group (p=0.07). We can conclude therefore that WT1 is mutated in 10% of normal karyotype AML, is positively associated with FLT3-ITD status and identifies a putative subgroup of normal karyotype AML who fail to achieve remission with conventional cytotoxic therapy and have a poor overall survival. Validation of this data in larger series would support the inclusion of WT1 in the current molecular risk stratification of normal karyotype AML based on CEBPA, NPM and FLT3-ITD status.

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Nucleotide Transition 390C-T in the Wilms' Tumor 1 Gene: A Risk Factor of Hypospadias?

Current Urology ◽

10.1159/000447167 ◽

2016 ◽

Vol 10 (3) ◽

pp. 136-139 ◽

Cited By ~ 2

Author(s):

Gergely Buglyó ◽

Ágnes Magyar ◽

Sándor Biró ◽

István Csízy ◽

Dániel Beyer ◽

...

Keyword(s):

Copy Number ◽

Nucleotide Substitution ◽

Wilms Tumor ◽

Phenotype Correlation ◽

Interacting Protein ◽

Wide Range ◽

Normal Copy Number ◽

Wilms Tumor 1 ◽

Wt1 Mutation ◽

Nucleotide Transition

Introduction: The gene Wilms' tumor 1 (WT1) encodes a unique transcription factor. Its defects are known to cause a wide range of complex genitourinary malformations and may contribute to non-syndromic forms of hypospadias. Materials and Methods: We performed WT1 mutation analysis and copy number analysis of WT1-interacting protein in 13 Hungarian patients diagnosed with isolated hypospadias. Results: Sequencing of WT1 revealed a high frequency of heterozygosity for transition 390C-T (5 heterozygotes out of 13 patients, including 2 brothers). WT1-interacting protein had a normal copy number in all patients. Conclusion: Nucleotide substitution 390C-T may play a role in the pathogenesis of non-syndromic hypospadias. The genotype-phenotype correlation should be confirmed by a larger-scale analysis.

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