Multiplex Real-time RT–PCR for Prospective Evaluation ofWT1and Fusion Gene Transcripts in Newly DiagnosedDe NovoAcute Myeloid Leukemia

Abstract

Prognostic assessment is crucial for the management of AML. Although the use of karyotype analysis for risk-stratification is widely accepted, prognosis of AML remains ambiguous, particularly for patients categorized into the intermediate cytogenetic risk group and additional markers are required for an accurate prediction of outcome. For this study, we used multiplex real-time RT-PCR, which can simultaneously quantify WT1 and 10 distinct fusion gene transcripts, to prospectively evaluate the pre-treatment bone marrow findings of 53 de novo AML patients. Five patients with normal karyotype or insufficient metaphases detected by conventional karyotype analysis proved to have AML1-MTG8, CBFbeta-MYH11 or PML-RARalpha fusion transcripts. WT1 overexpression was observed in 92% of the patients, and the levels were significantly higher in the cytogenetic favorable risk group, especially patients with PML-RARalpha. WT1 levels also correlated with the percentage of blasts in bone marrow, especially in cases of core-binding factor leukemia. There was no association between initial WT1 levels and outcome in terms of event-free survival or overall survival. These results suggest that multiplex real-time RT-PCR is rapid and useful for the precise cytogenetic stratification of AML, and that WT1 levels at presentation correlate with several biologic features of leukemia, but have no prognostic significance.

Expression of tumor-associated antigens in acute myeloid leukemia: implications for specific immunotherapeutic approaches

“…In accordance with our data in patients with AML, the expression of G250/CA9 has also been shown to be associated with a favorable outcome in RCC. [40][41][42] While some studies have shown a poor clinical outcome of patients with AML expressing WT1 in the leukemic blasts, 33,43 others described no correlation of WT1 expression with the clinical outcome, 34,44 which is in agreement with our findings.…”

“…For PRTN3 and WT1, the correlation of expression levels and clinical outcome has been controversially discussed recently. 33,34 Our data did not show a correlation with clinical outcome (Figure 1D-E). While there was also no correlation of TERT or LAMR1 expression levels with outcome ( Figure 1F-G), higher BCL2 levels suggested poorer overall survival although not statistically significantly (P ϭ .250; log-rank test; Figure 1H).…”

Prognostic significance of diagnosed WT1 level in acute myeloid leukemia: a meta-analysis

“…Six studies [9-11, 13, 20, 21] originated from Europe and five studies [8,12,[22][23][24] from Asia.…”

“…A correlation between diagnosed WT1 higher expression (WT1 H ) and poor outcome has previously been reported [5][6][7]. However, some studies did not confirm the negative impact on overall survival (OS) [8][9][10][11][12] or disease-free survival (DFS) [9,12,13]. Thus, it is necessary to perform a metaanalysis to further clarify the association between diagnosed WT1 H and outcome in AML patients.…”

Risk stratification of intermediate-risk acute myeloid leukemia: integrative analysis of a multitude of gene mutation and gene expression markers

“…For instance, expression of EVI1, [21][22][23] BAALC, 24,25 ERG, 26,27 and MN1 28,29 was proposed as indicators for treatment outcome in AML. Some expression markers, such as WT1, [30][31][32][33] BCL2, 34 INDO, 35 CD34, 36 ABCB1, 37 and FLT3, 38 have been put forward as clinical markers, but their applicability has been less well established or has been controversial.…”