Publication Date:
2014-12-06
Description:
Introduction: The Wilms’ tumor 1 (WT1) gene, located on chromosome 11p13, encodes a transcription factor. WT1 is overexpressed in 90% of patients with acute myeloid leukemia (AML) and thus can be used for minimal residual disease (MRD) monitoring by quantitative RT-PCR. The aim of the present study was to analyze the usefulness of WT1 as a marker for MRD quantification in AML after chemotherapy. Patients and Methods: This retrospective and multicentric study included 148 patients with WT1-overexpressed AML. Quantitative assessment of WT1 transcript levels was performed by quantitative RT-PCR in 370 bone marrow (BM) samples at diagnosis (148), post-induction (125) and post-consolidation (97). WT1 gene expression was calculated by relative quantification using the normalized ratio of the target gene (WT1) related to a reference gene (GUS) and using cell line K562 as calibrator. Inter-laboratories methodological standardization was accomplished through a pilot study with 20 BM donor samples, 20 BM patient samples and commercial WT1 plasmids (ProfileQuant Kit, Ipsogen-Qiagen). Results: No significant differences in WT1 gene expression (cycle threshold, Ct) were observed between different laboratories in the pilot study (kappa coefficient 〉0.7). The cut-off value of WT1 over-expression in BM was established for each laboratory (median+2SD values from healthy donors, data not shown). Median WT1 expression in patient samples at diagnosis was 38% (range, 2-850). Differential expression at diagnosis did not correlate with age, gender, leukocytes, karyotype (risk). However a significantly higher expression in patients with AML-M1 and AML-M2 subtypes as well as patients with mutant NPM1 and/or ITD-FLT3 was observed (p
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
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