1: Zhonghua Xue Ye Xue Za Zhi. 2003 May;24(5):256-8. [Detection of 29 types of fusion gene in leukemia by multiplex RT-PCR] [Article in Chinese] Li ZG, Wu MY, Zhao W, Li B, Yang J, Zhu P, Hu YM. Hematological Center, Beijing Children's Hospital, Beijing 100045, China. OBJECTIVE: To analyze the fusion genes derived from 29 types of chromosome structural aberrations in children with leukemia. METHODS: Bone marrow samples from 191 children with leukemia were analyzed with a novel multiplex nested RT-PCR. RESULTS: Of the 191 leukemic samples, 86 (45.0%) carried 14 types of fusion genes including SIL/TAL1, MLL/AF1q, E2A/PBX1, MLL/AF6, AML1/ETO, MLL/AF9, TEL/ABL, BCR/ABL, MLL/AF10, dupMLL, MLL/ENL, TEL/AML1, PML/RARalpha and CBFbeta/MYH11. The activation of oncogene HOX11 was detected in 31 cases, with or without other chromosome aberrations in 15 (7.8%) and 16 cases (8.4%), respectively. CONCLUSION: This multiplex nested RT-PCR reaction could screen 29 types of chromosome structural aberrations at the same time. It may be helpful for the detection of minimal residual diseases after chemotherapy and bone marrow transplantation. PMID: 12859878 [PubMed - in process] --------------------------------------------------------------- 2: Haematologica. 2003 Mar;88(3):275-9. A multiplex reverse transcriptase-polymerase chain reaction strategy for the diagnostic molecular screening of chimeric genes: a clinical evaluation on 170 patients with acute lymphoblastic leukemia. Elia L, Mancini M, Moleti L, Meloni G, Buffolino S, Krampera M, De Rossi G, Foa R, Cimino G. Dipartimento di Biotecnologie Cellulari ed Ematologia, Sezione di Ematologia, University La Sapienza, via Benevento 6, 00161 Rome, Italy. BACKGROUND AND OBJECTIVES: In the last few years molecular methods have allowed the identification of leukemia-associated genetic lesions, which may represent the most accurate predictors of clinical outcome. These considerations strengthen the need for rapid identification of the abnormalities. Our aim was to demonstrate whether a modified multiplex reverse transcription polymerase chain reaction (RT-PCR) system might be successfully used to screen a large number of patients with acute lymphoblastic leukemia (ALL). DESIGN AND METHODS: In this study we adapted the multiplex RT-PCR assay, previously described by Pallisgaard et al., to detect all the most frequent genetic lesions with their characteristic splicing variants occurring in acute lymphoblastic leukemia, such as the MLL/AF4, MLL/ENL, BCR/ABL p190 (e1a2) and p210 (b2a2,b3a2) isoforms, E2A/PBX1, TEL/AML1, SIL/TAL1 and the novel NUP98/RAP1GDS1 transcript, recently described in a T-ALL leukemic subtype. RESULTS: We used the multiplex RT-PCR assay to screen 170 ALL patients (70 children and 100 adults). PCR positivity was detected in 67 (39%) of the 170 ALL patients studied. The comparison between cytogenetic and molecular analyses showed complete correspondence between the two assays in all patients with an evaluable karyotype. Finally, the observed incidence of genetic lesions in our ALL patients was similar to the frequency usually reported both in children and in adults with ALL. INTERPRETATION AND CONCLUSIONS: These results show that, compared to single RT-PCR reactions, our multiplex RT-PCR system allows rapid, specific, simultaneous as well as a less expensive, laborious and time-consuming detection of the most frequent fusion transcripts in ALL patients. Therefore, it might be recommended for rapid diagnostic molecular screening of large numbers of patients, such as those enrolled in multicenter, co-operative studies. Furthermore, we have shown that multiplex RT-PCR is an open system that can easily be adapted to detect new leukemic genes. PMID: 12651265 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 3: Leukemia. 1999 Dec;13(12):1901-28. Standardized RT-PCR analysis of fusion gene transcripts from chromosome aberrations in acute leukemia for detection of minimal residual disease. Report of the BIOMED-1 Concerted Action: investigation of minimal residual disease in acute leukemia. van Dongen JJ, Macintyre EA, Gabert JA, Delabesse E, Rossi V, Saglio G, Gottardi E, Rambaldi A, Dotti G, Griesinger F, Parreira A, Gameiro P, Diaz MG, Malec M, Langerak AW, San Miguel JF, Biondi A. Department of Immunology, University Hospital Rotterdam/Erasmus University Rotterdam, Rotterdam, The Netherlands. Prospective studies on the detection of minimal residual disease (MRD) in acute leukemia patients have shown that large-scale MRD studies are feasible and that clinically relevant MRD-based risk group classification can be achieved and can now be used for designing new treatment protocols. However, multicenter international treatment protocols with MRD-based stratification of treatment need careful standardization and quality control of the MRD techniques. This was the aim of the European BIOMED-1 Concerted Action 'Investigation of minimal residual disease in acute leukemia: international standardization and clinical evaluation' with participants of 14 laboratories in eight European countries (ES, NL, PT, IT, DE, FR, SE and AT). Standardization and quality control was performed for the three main types of MRD techniques, ie flow cytometric immunophenotyping, PCR analysis of antigen receptor genes, and RT-PCR analysis of well-defined chromosomal aberrations. This study focussed on the latter MRD technique. A total of nine well-defined chromosome aberrations with fusion gene transcripts were selected: t(1;19) with E2A-PBX1, t(4;11) with MLL-AF4, t(8;21) with AML1-ETO, t(9;22) with BCR-ABL p190 and BCR-ABL p210, t(12;21) with TEL-AML1, t(15;17) with PML-RARA, inv (16) with CBFB-MYH11, and microdeletion 1p32 with SIL-TAL1. PCR primers were designed according to predefined criteria for single PCR (external primers A <--> B) and nested PCR (internal primers C <--> D) as well as for 'shifted' PCR with a primer upstream (E5' primer) or downstream (E3' primer) of the external A <--> B primers. The 'shifted' E primers were designed for performing an independent PCR together with one of the internal primers for confirmation (or exclusion) of positive results. Various local RT and PCR protocols were compared and subsequently a common protocol was designed, tested and adapted, resulting in a standardized RT-PCR protocol. After initial testing (with adaptations whenever necessary) and approval by two or three laboratories, the primers were tested by all participating laboratories, using 17 cell lines and patient samples as positive controls. This testing included comparison with local protocols and primers as well as sensitivity testing via dilution experiments. The collaborative efforts resulted in standardized primer sets with a minimal target sensitivity of 10-2 for virtually all single PCR analyses, whereas the nested PCR analyses generally reached the minimal target sensitivity of 10-4. The standardized RT-PCR protocol and primer sets can now be used for molecular classification of acute leukemia at diagnosis and for MRD detection during follow-up to evaluate treatment effectiveness. Publication Types: Review Review, Tutorial PMID: 10602411 [PubMed - indexed for MEDLINE] ---------------------------------------------------------------