[Biological microchip for establishing the structure of fusion transcripts involving MLL in children with acute leukemia].

MLL is involved in fusion genes with more than 100 partner genes, approximately 80 of which have been characterized at the molecular level. MLL fusion genes are often found in infants (60-80% of acute lymphoblastic leukemia (ALL) cases and 40-50% of acute myeloblastic leukemia (AML) cases) and are appreciably rarer (8-10%) in children older than 1 year of age. MLL rearrangements are important markers in diagnosis and treatment choice. To identify the partner gene is of primary importance for prognosis and minimal residual disease monitoring. The structure of the fusion gene, including localization of the MLL breakpoints, is also informative. A method was developed to examine the fusion transcripts in order to identify the partner gene among the six most common ones and to establish the exon structure of the rearranged MLL. The method includes a multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) to amplify and to fluorescently label a fusion transcript fragment and subsequent hybridization of the product on a biological microchip with immobilized oligonucleotides complementary to exons of MLL and its partner genes AFF1, MLLT1, MLLT3, MLLT4, MLLT10, and ELL. Hybridization results were verified by sequencing the RT-PCR products and, in some cases, performing long-distance inverse PCR (LDI-PCR). The study involved 38 bone marrow samples from ALL patients (including 33 children younger than 1 year of age) and 15 samples from AML patients (including 10 from children younger than 1 year of age). The main partner genes were AFF1 (49%), MLLT1 (27%), MLLT3 (12%), and MLLT10 (12%) in ALL and MLLT3 (80%), MLLT10 (10%), and MLLT4 (10%) in AML. Fusion gene transcripts most commonly included MLL exon 11 (58% of ALL cases and 50% of AML cases), suggesting a breakpoint in MLL intron 11.

[Efficiency of the ALL-MB-2002 protocol in children with acute lymphoblastic leukemia].

AIM: To evaluate the efficiency of the original ALL-MB-2002 protocol within the multicenter study of treatment of acute lymphoblastic leukemia (ALL) in children. SUBJECTS AND METHODS: A total of 1873 primary patients with ALL aged 1 to 18 years, of whom 1544 patients were enrolled in this study, were notified at 36 clinics of Russia and Belarus from April 15, 2002, to January 1, 2008. RESULTS: With the median observation of 4.12 years, 7-year event-free survival (EFS) was 73 +/- 13%; overall survival (OS) 78 +/- 2%; relapse-free survival 82 +/- 1%. The rates of EFS and OS were equal and amounted to 76 +/- 2 and 80 +/- 2% in the standard-risk group (SRG) and intermediate-risk group (ImRG), respectively. In the high-risk group (HRG) patients, EFS and OS were as high as 30 +/- 6 and 37 +/- 6%, respectively. The frequency of relapses with central nervous system lesion was as much as 4.7% in all the patients, 6-year cumulative risk for isolated neurorecurrences being 2.5% in the SRG patients. Adolescents, patients with the baseline leukocytosis (more than 100 x 10(9)/l), and those with a splenic size of over 4 cm or more from the costal arch margin had substantially worse survival rates. A poor early response to therapy (on induction days 8 and 15) was also associated with its lower efficiency. CONCLUSION: Despite a considerable rise in the number of centers and a slight increase in the intensity of therapy, the results of the new ALL-MB-2002 protocol are as minimum equivalents obtained in the use of the previous ALL-MB-91 protocol. A significant improvement in the overall results of therapy and a reduction in the cumulative risk for isolated neurorecurrences were noted in the ImRG patients.

[The results of a multicenter trial of acute lymphoblastic leukemia treatment on ALL-MB 91/ALL-BFM 90m in children: analysis of efficacy and toxicity].

AIM: A comparative analysis of efficacy and toxicity of two chemotherapy regimens: standard German protocol ALL-BFM 90m and less intensive original test protocol ALL-MB 91 in a multicenter trial of acute lymphoblastic leukemia (ALL) in children. MATERIAL AND METHODS: In 1995-2002 a total of 834 patients with newly diagnosed ALL aged 0-18 years were admitted to 10 clinics of Russia. Of them, 713 were randomized in two groups: treatment program ALL-BFM 90m (n = 355) and ALL-MB 91 program (n = 358). RESULTS: In 7-year follow-up median, 10-year event-free survival (EFS) and overall survival (OS) did not differ significantly between the groups and was 67 +/- 3 and 68 +/- 3% (ALL-MB 91) and 74 +/- 2, 71 +/- 3% (ALL-BFM 90m), respectively. Though the rate of isolated recurrences in CNS in patients on the protocol ALL-MB 91 was 2.8%, they developed only in 0.8% patients of the standard risk group. Anemia, thrombocytopenia and agranulocytosis developed less frequently, hospital stay was significantly shorter on the test protocol vs the control one (p < 0.01). CONCLUSION: EFS and OS on the test (ALL-MB 91) and control (ALL-BFM 90m) protocols were equivalent in lower toxicity and cost of therapy.

[Results of the treatment of childhood acute lymphoblastic leukemia according to the Berlin-Moscow-91 protocol in 1991-2000]. / Rezul'taty lecheniia ostrogo limfoblastnogo leikoza u detei po protokolu Moskva-Berlin-91 v 1991-2000 gg.

The report deals with the results of application of an original protocol--the Berlin-Moscow-91 (BM-91)--for the treatment of acute lymphoblastic leukemia (ALL) in children. The researchers' major concern was to improve survival and cut down side-effects incidence as well as to prevent and successfully manage occult neuroleukemia as a potential source of relapse. Patients aged 5 months-15 years received the BM-91 and ALL BFM-90m treatment first at one clinic and later at several centers. Out of 852 children with primary diagnosis of ALL admitted to Russian hematological hospitals (March 2, 1991-November 3, 2000), 687 were included into the study; 329 received the MB-91 protocol. Nine-year recurrence-free survival was 73% while overall survival--80%. Toxic side-effects after L-asparaginase were reported in 27 (7.9%). It is concluded that good results in childhood ALL treatment can be achieved without resorting to high-dosage chemotherapy and radiation in most cases.

[Treatment of acute lymphoblastic leukemia in children according to the ALL-BFM-90m protocol in the Russian Federation and the Republic of Belarus]. / Lechenie ostrogo limfoblastnogo leikoza u detei po protokolu OLL-BFM-90m v Rossiiskoi Federatsii i Respublike Belarus'.

Prognosis for children treated according to the BFM-90m protocol (Berlin-Frankfurt-Munster Group) for acute lymphoblastic leukemia (ALL) improved significantly as compared with previous modalities. Methotrexate was used in the dose of 1,000 mg/m2, 36 h. The paper presents the 10-year results for this modification. Patients aged 0-15 years were treated at hematological hospitals of Moscow, other Russian towns and in Minsk, Belarus, (July 5, 1990-November 11, 2000). BFM-90m treatment was given to 682 children out of 1,326 with primary diagnosis of ALL; a comparative trial of the MB-91 protocol hed been carried out at the same clinics since 1991. During 10 years, recurrence-free survival was 72% while overall survival--77%. Toxicity of side-effects was tolerable. The BFM-90m treatment showed significantly better results in both countries.

[Results of treatment of acute leukemia in children using intensive therapy programs]. / Rezul'taty lecheniia ostrykh leikozov u detei s ispol'zovaniem programm intensivnoi terapii.

The authors report the results of the treatment according to the programs BFM-ALL-90 and BFM-AML-83 and 87. A total of 110 children with acute lymphoblastic leukemia (ALL) and 35 with acute myeloblastic leukemia (AML) were treated with remission rate 94.5% and 74.5%, respectively. Under programmed treatment of ALL the recurrences occurred in 12.2% against 46% of the cases in nonprogrammed treatment. 2-year survival made up 75% and 47.3%, respectively. Among AML cases there were frequently prognostically unfavorable ones and patients with neuroleukemia this dictating the necessity of the treatment intensification and irradiation of the skull in AML. Improvement of adjuvant therapy is a must in advance of acute leukemia treatment.

[Comparative effectiveness of treatment of non-Hodgkin's lymphoma in children using protocols BFM NHL-90 and non-programmed courses based on the ACOP regimen]. / Sravnitel'naia éffektivnost' lecheniia nekhodzhkinskikh limfom u detei po protokolam BFM NHL-90 i nonprogrammnym kursam na osnove rezhima ATsOP.

170 NHL children aged 1-14 [mean age 6] have been treated for the last 5 years. The diagnostic examination included the disease history, physical examination, bone marrow cytology, tumor histology (all patients), immunophenotyping (17 cases), x-ray and sonography of the chest and abdomen. According to the International NHL staging system, 35% of the patients had NHL stage II, 65% stage III or IV. The study entered 71 patients who underwent additional lactate dehydrogenase test, CT-scanning. 44 of them received nonprogrammed therapy on the basis of ACOP (group I), 27 patients were treated according to BFM-NHL-90 for B-, non-B- and large-cell anaplastic lymphomas (group II). The efficiency of the methods did not differ for patients at stage IIR. At the II NR stage complete remission (CR) was up to 41% in the group I and 60% in the group II. 50% of the children from group I and 20% from the group II were resistant to treatment. All the group I patients developed relapses, none got relapses in the group II. CR was observed in 64% and 78% of patients from group I and II, respectively, who had NHL stage III and IV. Relapses occurred in 41% and 14%, respectively. CCR was in 22% in the group I and in 67% of the group II patients. Effectiveness of B-NHL treatment according to BFM protocols was higher than in other types of NHL as to the number of relapses and frequency of CCR: the latter was 76% compared to 50% of non-B-NHL.(ABSTRACT TRUNCATED AT 250 WORDS)