title: Quantification of TEL-AML1 transcript for minimal residual disease assessment in childhood acute lymphoblastic leukaemia.
abstract: Strategies currently used for residual disease detection in acute lymphoblastic leukaemia (ALL) rely on polymerase chain reaction (PCR) detection of immunoglobulin and T-cell receptor rearrangements. The TEL-AML1 fusion transcript, which is associated with t(12;21) (p13;q22), is found in 25% of childhood B-cell precursor ALL, and represents an interesting alternative target. We compared two methods for quantitating TEL-AML1 fusion transcripts: competitive PCR and real-time PCR. These techniques showed similar sensitivity (5 x 10(-5)) and reproducibility. Giving highly correlated results, both techniques can be conveniently used for TEL-AML1 transcript quantification. The constancy of TEL-AML1 expression was evaluated by measuring TEL-AML1 transcripts at different steps of the cell cycle, and in 21 cases of ALL at diagnosis. No major variation in TEL-AML1 expression was observed during the cell cycle or in 20/21 of the ALL patients. Residual disease was then determined after completion of induction therapy in 20 patients with a TEL-AML1-positive ALL. Seven patients out of 20 (35%) were still positive, including two patients with high level of residual blasts (close to or beyond 10(-2)). When comparison was possible, results obtained using TEL-AML1 quantification were in accordance with those obtained using T-cell receptor rearrangements analysis.
authors.affiliation: Laboratoire de Biochimie Génétique, Hôpital Robert Debré, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Drunat
authors.forename: M
authors.initials: M
authors.lastname: Olivi
authors.forename: G
authors.initials: G
authors.lastname: Brunie
authors.forename: B
authors.initials: B
authors.lastname: Grandchamp
authors.forename: E
authors.initials: E
authors.lastname: Vilmer
authors.forename: I
authors.initials: I
authors.lastname: Bièche
authors.forename: H
authors.initials: H
authors.lastname: Cavé
mesh_terms: D002648:Child; D002675:Child, Preschool; D050676:Core Binding Factor Alpha 2 Subunit; D005260:Female; D005500:Follow-Up Studies; D015870:Gene Expression; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D007223:Infant; D008297:Male; D018365:Neoplasm, Residual / Q000175:diagnosis*; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000188:drug therapy; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000097764:ETS Translocation Variant 6 Protein
chemical_list: D050676:Core Binding Factor Alpha 2 Subunit; D015514:Oncogene Proteins, Fusion; C102421:TEL-AML1 fusion protein; D000097764:ETS Translocation Variant 6 Protein