Underestimation of inversion (16) in acute myeloid leukaemia using standard cytogenetics as compared with polymerase chain reaction: results of a prospective investigation

Abstract

Summary. In order to determine whether the polymerase chain reaction (PCR) is more suitable for the detection of inversion (16) as compared with standard cytogenetics, we prospectively investigated a total of 132 cases of de novo acute myeloid leukaemia (AML) (n ¼ 121) and secondary AML after myelodysplastic syndromes (MDS) (n ¼ 11) using a sensitive and nested PCR procedure to detect the fusion transcripts CBFb-MYH11. All patients were recruited within 10 months in an ongoing multicentre AML-trial. In addition, several cases from a retrospective molecular analysis were included. The data were compared with standard cytogenetics performed in a central laboratory. Of the 132 prospective AML cases, five patients (3 . 7%) harboured inv(16) upon conventional cytogenetics. In all cases fusion transcripts CBFb-MYH11 were detected using PCR. In addition in two patients fusion transcripts were detected, although cytogenetics revealed a normal karyotype. In the group of patients analysed retrospectively, four patients harboured fusion transcripts specific for CBFb-MYH11; cytogenetics were normal in one case, and could not be evaluated in two cases. These data show that PCR may be a better means to detect inv(16) in AML. Since inv(16) may have prognostic impact in AML, detection of this aberration seems important in the clinical management of AML patients.

Prophylactic transfer of BCR-ABL–, PR1-, and WT1-reactive donor T cells after T cell–depleted allogeneic hematopoietic cell transplantation in patients with chronic myeloid leukemia

“…In brief, white blood cells were obtained after erythrocyte lysis from peripheral blood and bone marrow samples, with approximately 5 ϫ 10 5 to 1 ϫ 10 7 cells being used for RNA extraction by the RNeasy Blood kit (QIAGEN). Complementary DNA synthesis was performed as described, 32 and up to 5 L of complementary DNA was used for real-time PCR. All reactions were performed in duplicate.…”

Sequential monitoring of chimerism and detection of minimal residual disease after allogeneic blood stem cell transplantation (BSCT) using multiplex PCR amplification of short tandem repeat-markers

“…RNA extraction and reverse transcription were performed as described recently. 30 First round PCR for the AML1-ETO rearrangement associated with the translocation t(8;21) was performed in PE 9600 thermocyclers using primers AML2 (5′-CCTCAGGTTTGTCGGTCGAAGTGGA-3′) and ETO4 (5′-GCTGTAGGAGAATGGCTCGTGCCA-3′). Total volume of the PCR reaction was 25 l, containing 200 mol/l deoxynucleoside-triphosphates, 0.001% gelatine, 50 mmol/l KCl, 1.5 mmol/l MgCl 2 , 10 mmol/l Tris-HCl, 500 nmol/l of the primers and 1 U of Taq-polymerase (AmpliTaq, PE Biosystems, Weiterstadt, Germany).…”

Screening for core binding factor gene rearrangements in acute myeloid leukemia

“…Therefore, in cases of AML lacking the classic t(8;21) one should be alerted to the possibility of a cryptic AML1-ETO rearrangement on detection of del(9q) and/or loss of a sex chromosome, 10,22,32 or of a cryptic CBF␤-MYH11 fusion in the presence of +22, 13,14,16,33,34 particularly in conjunction with suggestive morphology. However, it should be appreciated that although cases with cryptic AML1-ETO gene fusions may share the distinctive morphological features associated with the t(8;21) and those with cryptic CBF␤-MYH11 fusions may exhibit an M4eo phenotype, this is not invariably the case 10,11,13,14,16,23,33,35,36 suggesting that molecular screening should not be solely targeted to such patients. Furthermore, the majority of cases of AML with del(9q) or +22 have been shown not to have underlying cryptic CBF gene rearrangements.…”