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A Reiter

Publications and source records attributed to A Reiter.

At least 73 records · Page 4Linked to original sources

Maternal stress during pregnancy, its objectivation by ultrasound observation of fetal intrauterine movements and child's temperament at 6 months and 6 years of age: a pilot study.

Niederhofer showed in 1994 that maternal stress during pregnancy seemed associated with development of personality in early childhood. This study examined the correlation between maternal stress during pregnancy for 121 women, its ultrasound objectivation by observation of intrauterine fetal movements, child's temperament in early childhood, and child's marks at the age of 6 years while controlling for possible confounding variables. Only intrauterine fetal movements were not associated either with stress during pregnancy or early personality.

Child↗

Confirmation of paternal disomy in a twin molar pregnancy. A case report.

BACKGROUND: Paternal dispermy can be the pathogenesis of complete molar pregnancy. CASE: A 23-year-old, white woman, gravida 4, para 1, was pregnant with a twin gestation by ovulation induction with metrodin. Ultrasound evaluation confirmed an intrauterine pregnancy in conjunction with what appeared to be a hydatidiform mole. The karyotype in the molar pregnancy, obtained from chorionic villus sampling, showed a pair of paternally derived inverted chromosomes 9, confirming the diagnosis of a complete mole. Uncontrollable hemorrhage with a rapid rise in the beta-human chorionic gonadotropin titer necessitated evacuation of the uterus. The patient was followed with beta-human chorionic gonadotropin titers for a year, with no evidence of recurrence. CONCLUSION: This case illustrates paternal disomy in a complete molar pregnancy documented by a paternal chromosome 9 inversion.

Adult↗

Non-Hodgkin's lymphoma in pediatric patients with chromosomal breakage syndromes (AT and NBS): experience from the BFM trials.

BACKGROUND: Lymphoma and leukemia are the commonest malignant diseases in patients with chromosomal breakage syndromes and immunodeficiency (Ataxia teleangiectasia (AT) and Nijmegen breakage syndrome (NBS)). With improved management of infections, malignant disease is more frequently diagnosed and has become one of the commonest causes of death in pediatric AT and NBS. PATIENTS AND METHODS: In three consecutive multicenter therapy trials for pediatric non-Hodgkin's lymphoma (NHL) (NHL-BFM), 1569 patients with newly diagnosed NHL have been registered between 1986 and 1997. Nine patients with AT (n = 5) and NBS (n = 4) were identified and analysed. RESULTS: Median age of patients with AT and NBS at diagnosis of NHL was nine years. NHL-entities differed from non-AT/NBS-patients: diffuse large B-cell lymphomas, n = 7 (78%); ALCL, n = 1; lymphoblastic T-cell lymphoma, n = 1. Cervical nodes, paranasal sinuses and epipharynx were the sites most frequently involved. Stages were: I and II in three patients, III in five and IV in one patient. All patients received polychemotherapy according to tumor-entity and stage, none received radiation. Dose reductions according to individual tolerance concerned mainly ethotrexate, alkylating agents and epipodophyllotoxines. One patient died of toxic complications, two patients relapsed and died, one patient suffered from second malignancy. Five of nine patients are in 1. CCR after a median follow-up of five years. CONCLUSIONS: Patients with AT and NBS suffer from rare entities of pediatric NHL. Curative treatment is possible and should be attempted. Intensity of therapy should be adjusted to individual risk factors and tolerance. Alkylating agents, epipodophyllotoxines should be omitted, dose of MTX should be limited to 1 g/m2. Further cooperative trials using standardized approaches are required.

Adolescent↗

Sudden unexpected infant death due to fibroma of the heart.

A 7-month-old previously healthy female infant was found dead in her crib by her mother shortly after having been laid down to sleep following the noontime feeding. Because the child did not suffer from an acute illness and no other evidence pointed to a cause of death, it was initially assumed by the police that she had died of sudden infant death syndrome. At autopsy, however, the cause of death was determined to be cardiac arrhythmia secondary to fibroma of the heart.

Cause of Death↗

Identification of three distinct regions of deletion on the long arm of chromosome 11 in childhood acute lymphoblastic leukemia.

Cytogenetic analysis of childhood acute lymphoblastic leukemia (ALL) identified deletions of chromosome arm 11q. These observations led us to analyse the loss of heterozygosity (LOH) of chromosome arm 11q in 113 primary childhood ALL samples using 14 microsatellite markers. LOH was found in 18 (16%) patients. Detailed examination identified three distinct regions of deletion. The first region is flanked by D11S901 and D11S1391 at 11q22-23 containing the ATM gene. Mutational analysis suggested that the altered gene in this region is not the ATM gene. The second region is flanked by D11S614 and D11S924 at 11q23 containing the MLL gene. The third region is flanked by D11S1356 and D11S614 at 11q23 containing the MLL gene. All the cases with LOH at MLL locus lacked detectable MLL gene rearrangements. In addition, 20 children have been studied both at initial diagnosis and relapse; none of the individuals who relapsed acquired LOH of 11q, suggesting that 11q deletions were infrequently involved in the progression of childhood ALL. Children with 11q LOH had a good response to induction chemotherapy (P=0.015). These data suggest that alterations of putative tumor suppressor genes on 11q are important events in development of childhood ALL. Our map provides important information toward cloning putative tumor suppressor genes associated with childhood ALL.

Child↗

Improved treatment results in childhood B-cell neoplasms with tailored intensification of therapy: A report of the Berlin-Frankfurt-Münster Group Trial NHL-BFM 90.

In study NHL-BFM 90, we investigated whether the serum lactate dehydrogenase (LDH) concentration and early response are useful markers for stratification of therapy for childhood B-cell neoplasms in addition to stage, if the outcome of patients with abdominal stage III and LDH >/=500 U/L can be improved by high-dose (HD) methotrexate (MTX) at 5 g/m(2) instead of intermediate-dose (ID) MTX at 500 mg/m(2) in the preceding study 86; whether 2 therapy courses are enough for patients with complete resection; and whether combined systemic and intraventricular chemotherapy is efficacious for central nervous system-positive (CNS(+)) patients. After a cytoreductive prephase, treatment was stratified into 3 risk groups: patients in R1 (completely resected) received 2 5-day courses (ID-MTX, dexamethasone, oxazaphorins, etoposide, cytarabine, doxorubicin, and intrathecal therapy), patients in R2 (extra-abdominal primary only or abdominal tumor and LDH <500 U/L) received 4 courses containing HD-MTX, and patients in R3 (abdominal primary and LDH >/=500 U/L or bone marrow/CNS/multilocal bone disease) received 6 courses. Incomplete responders after 2 courses received an intensification containing HD-cytarabine/etoposide. Patients with no or necrotic tumor thereafter received 3 more courses; 6 patients with viable tumor received autologous bone marrow transplantation. From April 1990 through March 1995, 413 evaluable patients were enrolled (R1, 17%; R2, 40%; and R3, 43%). The 6-year event-free survival (pEFS) was 89% +/- 2% for all and 100%, 96% +/-2%, and 78% +/- 3% in R1, R2, and R3, respectively. The pEFS of patients with abdominal stage III and LDH >/=500 U/L was 81% +/- 4% as compared with 43% +/- 10% in study 86. Of 26 CNS(+) patients, 5 died early, but only 3 relapsed.

Adolescent↗

Prednisone response is the strongest predictor of treatment outcome in infant acute lymphoblastic leukemia.

To define prognostic factors in infant acute lymphoblastic leukemia (ALL), the outcome of 106 infants (age </=12 months) during 3 consecutive multicenter trials of the Berlin-Frankfurt-Münster group (ALL-BFM 83, 86, and 90) was retrospectively analyzed according to presenting features and early in vivo response to prednisone. The prednisone response was defined as the cytoreduction (number of blood blasts per microliter at day 8) to a 7-day prednisone prephase and 1 intrathecal dose of methotrexate on day 1. Prednisone good responder (PGR; <1,000 blasts/microL) received conventional therapy and prednisone poor responder (PPR; >/=1,000 blasts/microL) received intensified therapy. Infant ALL was characterized by a high incidence of a white blood cell count greater than 100 x 10(3)/microL (57%), central nervous system leukemia (24%), lack of CD10 expression (59%), 11q23 rearrangement (49%) including the translocation t(4;11) (29%), and a comparatively high proportion of PPR (26%), which were all significantly associated with inferior outcome by univariate analysis. The estimated probability for an event-free survival at 6 years (pEFS) was by far better for PGR compared with PPR, who had a dismal prognosis despite intensified treatment (pEFS, 53% +/- 6% v 15% +/- 7%, P =.0001). Infant PGR, who were less than 6 months of age (n = 40), lacked CD10 expression (n = 43), and/or had an 11q23 rearrangement (n = 17) fared significantly better compared with corresponding PPR, as indicated by a pEFS of 44% +/- 8%, 49% +/- 8%, and 41% +/- 12%, respectively. In multivariate analysis, PPR was the strongest adverse prognostic factor (relative risk, 3.3; 95% confidence interval, 1.9 to 5.8; P <.0001). Infants with PGR, comprising a major subgroup (74%) among infants, might successfully be treated with conventional therapy, whereas PPR require new therapeutic strategies, including early treatment intensification or bone marrow transplantation in first remission.

Antineoplastic Agents, Hormonal↗

Synthesis of Pseudomonas aeruginosa lipopolysaccharide core antigens containing 7-O-carbamoyl-L-glycero-alpha-D-manno-heptopyranosyl residues.

The monosaccharide allyl 7-O-carbamoyl-L-glycero-alpha-D-manno- heptopyranoside, the reducing disaccharide 7-O-carbamoyl-L-glycero-alpha-D- manno-heptopyranosyl-(1-->3)-L-glycero-D-manno-heptopyranose and the disaccharides allyl 7-O-carbamoyl-L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)-L-glycero- beta- and alpha-D-manno-heptopyranoside were prepared in good yields. The 7-O-carbamoyl substituent was regioselectively introduced via NH3-NH4HCO3 treatment of a 6,7-O-carbonate group. Glycosylation steps were carried out using Me3SiOTf or BF3.Et2O promoted coupling of allyl alcohol with trichloroacetimidate or fluoride glycosyl donors, respectively. The deprotected allyl glycosides were reacted with cysteamine to afford spacer glycosides which were subsequently linked to bovine serum albumin. The artificial antigens which are related to the dephosphorylated heptose region of the lipopolysaccharide core region from Pseudomonas aeruginosa classified into RNA group I may be used for the characterization of monoclonal antibodies directed against inner core epitopes of human-pathogenic Pseudomonas species.

Carbohydrate Conformation↗

Transplantation of megadoses of purified haploidentical stem cells.

Peripheral mobilized parental CD34+ progenitors were isolated and used for the hematopoietic reconstitution after a myeloablative therapy in 23 pediatric patients with various diseases. Fourteen donors were human leukocyte antigen (HLA) three-loci mismatches, 6 donors were two-loci and 3 donors were one-locus mismatches. For depletion of T-lymphocytes, a positive selection of the mobilized peripheral CD34+ progenitors using the method of magnetic-activated cell sorting (MACS) was used. The purity of the CD34+ cells after MACS-sorting was 98-99%, the average number of transplanted CD34+ cells was 14.2 x 10(6)/kg (range 5.4-3.9 x 10(6)/kg) and the average number of infused T-lymphocytes was 1.4 x 10(4)/kg. Due to this low T cell number, only a short-term or no prophylaxis of graft-versus-host disease (GVHD) was necessary and no GVHD was seen. A significant GVHD was only seen in patients after add-back of donor T-lymphocytes, which was performed in some patients for prevention of relapse or in patients who showed a transient mixed chimerism. Since the B lymphocyte contamination of the isolated CD34+ cells was low in the range of 0.2%, no Epstein-Barr virus (EBV)-associated lymphoproliferative syndrome was observed. A primary engraftment was seen in 18 patients. Nonengraftment and rejection occurred in three and two patients, respectively. In four of these 5 patients, a second transplant using purified CD34+ cells from the same donor after an immunological reconditioning regimen resulted in a complete and sustained hematopoietic reconstitution. The speed of the immunological recovery was dependent on the number of transplanted CD34+ cells and was more rapid if this number was > 20 x 10(6)/kg. Eleven of the 23 patients are alive and disease free with a median follow-up of 12 months (range 2-30). The main cause of death was relapse (7 patients), and only one fatal infection was seen. Our data suggest that the transplantation of megadoses of haploidentical CD34+ cells is a realistic therapeutic option for patients who otherwise have no suitable donor, and an alternative to the use of unrelated cord blood.

Adolescent↗

Fusion of ETV6 to the caudal-related homeobox gene CDX2 in acute myeloid leukemia with the t(12;13)(p13;q12).

The t(12;13)(p13;q12) is a rare, recurrent translocation reported in a range of hematological malignancies. We have analyzed the molecular basis of this lesion in three patients with acute myeloid leukemia (AML), two of whom were known to have chromosome 12 breakpoints within the ETV6 gene. Fluorescence in situ hybridization (FISH) with ETV6 cosmids indicated that this gene was also disrupted in the third patient, while the normal ETV6 allele was retained. 3' rapid amplification of cDNA ends (RACE) polymerase chain reaction (PCR) from bone marrow mRNA of this individual identified a novel sequence fused to ETV6 that was homologous to a region just upstream of the mouse CDX2 homeobox gene, the human homologue of which has previously been mapped to chromosome 13q12. PCR primers designed to amplify an ETV6-CDX2 fusion identified two major transcripts from this patient. First, a direct in-frame fusion between exon 2 of ETV6 and exon 2 of CDX2, and second, a transcript that had an additional sequence of unknown origin spliced between these same exons. Surprisingly, apparently normal CDX2 transcripts, usually expressed only in intestinal epithelium, were also detectable in cDNA from this patient. Neither normal nor fusion CDX2 mRNA was detectable in the two other patients with a t(12;13), indicating that this translocation is heterogeneous at the molecular level. Reverse transcription-PCR analysis showed that CDX2 mRNA, but not ETV6-CDX2 mRNA, was strongly expressed in 1 of 10 patients with chronic myeloid leukemia in transformation, suggesting that deregulation of this gene may be more widespread in leukemia. CDX2 is known to regulate class I homeobox genes and its expression in hematopoietic cells may critically alter the balance between differentiation and proliferation.

Aged↗

The genomic structure of ZNF198 and location of breakpoints in the t(8;13) myeloproliferative syndrome.

The t(8;13)(p11;q12) is the most common translocation associated with the 8p11 myeloproliferative syndrome and results in an identical mRNA fusion between ZNF198 at 13q12 and FGFR1 at 8p11 in all cases thus far reported. ZNF198 is a widely expressed gene that is predicted to encode a 1377-amino-acid protein with five Zn finger-related motifs known as MYM domains. To determine the genomic DNA structure of ZNF198, we employed bubble PCR from PAC clones with a panel of gene-specific primers. Sequencing of these products revealed that ZNF198 consists of 26 exons with the initiation codon located in exon 4. The t(8;13) results in a consistent mRNA fusion of ZNF198 exon 17 to FGFR1 exon 9. Notable features of the structure of ZNF198 include three noncanonical GC donor splice sites and the presence of an alternatively spliced intron within exon 4. Amplification of genomic DNA from six t(8;13) patients with primers to ZNF198 exon 17 and FGFR1 exon 9 yielded patient-specific products ranging in size from 500 bp to 2.5 kb, indicating that the positions of the breakpoints in the t(8;13) are tightly clustered. The positions of the six t(8;13) breakpoints were determined and found to be distributed across ZNF198 intron 17 and FGFR1 intron 8 with no apparent subclustering. No consistent sequence motifs, repeats, or topoisomerase II cleavage sites were found at or near the breakpoints. It remains unclear why the t(8;13) translocation breakpoints occur within such small genomic regions, and it is possible that strict ZNF198-FGFR1 coding requirements restrict the positions of the breakpoints.

Amino Acid Sequence↗

Therapy for non-Hodgkin lymphoma in children with primary immunodeficiency: analysis of 19 patients from the BFM trials.

BACKGROUND: Non-Hodgkin lymphomas (NHL) represent an important complication of primary immunodeficiency (ID), posing new therapeutic challenges in this patient population. This study analyzes clinical data and therapy results of pediatric patients with primary ID and NHL in three consecutive NHL-BFM trials. PROCEDURE: Retrospective analysis of children with primary ID and NHL, treated according to protocol NHL-BFM, was performed regarding clinical presentation, diagnostic features, therapy, and outcome. RESULTS: From October, 1986, to April, 1997, 19 of 1,413 newly diagnosed patients with NHL were registered as suffering from primary ID. Age at diagnosis of NHL was lower in patients with ID. Six patients suffered from humoral ID, 13 patients from combined ID (ataxia teleangiectasia n = 3; Nijmegen breakage syndrome n = 4; PNP deficiency n = 1; IL2 receptor defect n = 1, other combined ID n = 4). Thirteen lymphomas were of B-cell and six of T-cell-lineage. Four of thirteen patients with combined ID were diagnosed with T-NHL, nine with B-NHL. Two of six patients with humoral ID presented with T-NHL and four with B-NHL. NHL entities differed significantly between ID and non-ID patients (P < or = 0.01): centroblastic and immunoblastic lymphomas (31.6% vs. 8.1%), anaplastic large cell lymphoma (26.3% vs. 10.7%), Burkitt lymphoma and B-ALL (21% vs. 47. 8%). Seventeen patients received polychemotherapy. Therapy-related toxicity was increased in ID- compared to non-ID-patients. Three patients died of sepsis; three died of tumor progression; one patient relapsed; one died of BMT-related toxicity; one died of second malignancy. Ten patients are in first continuous remission after a median follow-up of 4 years. CONCLUSIONS: Curative treatment of NHL in the presence of primary ID is possible and should be attempted.

Adolescent↗

Accurate and rapid analysis of residual disease in patients with CML using specific fluorescent hybridization probes for real time quantitative RT-PCR.

We sought to establish a rapid and reliable RT-PCR approach for detection and quantification of BCR-ABL fusion transcripts using the LightCycler technology. This device combines rapid thermocycling with online detection of PCR product formation and is based on the fluorescence resonance energy transfer (FRET) between two adjacent hybridization probes carrying donor and acceptor fluorophores. A pair of probes was designed that was complementary to ABL exon 3, thus enabling detection of all known BCR-ABL variants and also normal ABL as an internal control. Conditions were established to amplify less than 10 target molecules/reaction and to detect one CML cell in 105 cells from healthy donors. To determine the utility of the assay, we quantified BCR-ABL and ABL transcripts in 254 samples (222 peripheral blood, 32 bone marrow) from 120 patients with CML after therapy with IFN-alpha (n = 219), allogeneic BMT (n = 17), chemotherapy (n = 11), or at diagnosis (n = 7). The level of residual disease in the 245 BCR-ABL positive specimens was expressed as the ratio of BCR-ABL/ABL. This ratio was compared to results obtained by three established methods from contemporaneous specimens. A highly significant correlation was seen between the BCR-ABL/ABL ratios determined by the LightCycler and (1) the BCR-ABL/ABL ratios obtained by nested competitive RT-PCR (n = 201, r = 0.90, P < 0. 0001); (2) the proportion of Philadelphia chromosome positive metaphases determined by cytogenetics (n = 81, P < 0.0001); and (3) the BCR ratio determined by Southern blot analysis (n = 122, P < 0. 0001). We conclude that real-time PCR with hybridization probes is a reliable and sensitive method to monitor CML patients after therapy. The major advantages of the methodology are (1) amplification and product analysis are performed in the same reaction vessel, avoiding the risk of contamination; (2) the results are standardized by the quantification of housekeeping genes; and (3) the complete PCR analysis takes less than 60 min.

Blotting, Southern↗

High cure rates and reduced long-term toxicity in pediatric Hodgkin's disease: the German-Austrian multicenter trial DAL-HD-90. The German-Austrian Pediatric Hodgkin's Disease Study Group.

PURPOSE: To further reduce therapy-related late effects in patients with pediatric Hodgkin's disease (HD) while maintaining the high cure rates achieved with vincristine, prednisone, procarbazine, and doxorubicin (OPPA) or OPPA/cyclophosphamide, vincristine, prednisone, and procarbazine (COPP) chemotherapy and involved-field radiotherapy. The risk of testicular dysfunction was addressed by substituting etoposide for procarbazine (OEPA) in the induction therapy for boys. Radiation doses and fields were further reduced. PATIENTS AND METHODS: Three hundred nineteen boys and 259 girls younger than 18 years with previously untreated HD, enrolled onto the study between 1990 and 1995, were allocated to treatment group (TG)1 (early stages), TG2 (intermediate stages), or TG3 (advanced stages). All groups underwent two cycles of OEPA (boys) or OPPA (girls) for induction chemotherapy. TG2 and TG3 continued on additional two or four cycles, respectively, of COPP. Low-dose radiotherapy was given to the initially involved sites, ie, reduced involved fields. RESULTS: Initial response to OPPA or OEPA induction was virtually identical. Eight of 578 patients experienced early progression of HD. Thirty-seven relapses, three secondary tumors, and no secondary leukemias have been recorded, with a median follow-up duration of 5.1 years (maximum, 8.1 years). Thirteen of 578 patients died. The probability of 5-year event-free survival/overall survival is 91%/98% in the total group, 94%/97% with OPPA, and 89%/98% with OEPA induction therapy. Risk factor analysis showed two significant prognostic factors: histologic subtype NS2 and "B" symptoms. OEPA induction therapy, large mediastinal tumor, and age were not significant. Preliminary studies of testicular function indicate a lower risk of germ cell damage than previously documented with OPPA. CONCLUSION: OEPA is a satisfactory alternative to OPPA. Radiotherapy can be confined to involved sites when combined with appropriate chemotherapy. The DAL-HD-90 regimen represents a comprehensive treatment program for all stages of pediatric HD and offers a favorable benefit/risk ratio, combining excellent disease control, moderate acute toxicity, and reduced long-term toxicity.

Adolescent↗

Philadelphia chromosome-positive (Ph+) childhood acute lymphoblastic leukemia: good initial steroid response allows early prediction of a favorable treatment outcome.

Among 4,760 acute lymphoblastic leukemia (ALL) patients enrolled from 1986 to 1995 in two subsequent trials of the BFM and AIEOP study group, 61 patients were found to have Philadelphia chromosome-positive (Ph+) ALL. These patients were analyzed for presenting features and treatment outcome to identify specific prognostic factors. Treatment stratification was based on initial cell mass and early response as determined by blast count in peripheral blood after a 7-day induction prephase with prednisone and one dose of intrathecal methotrexate on day 1. All patients were treated by similar intensive Berlin-Frankfurt-Münster (BFM) protocols. The median age of Ph+ patients was 7.5 years, the median white blood cell count (WBC) was 75 x 10(9)/L, 77% of patients had common ALL, and 29% coexpressed myeloid markers. After a median observation time of 4.2 years, 29 of 61 patients are alive (survival probability [pSUR] at 4 years, 0.49; standard error [SE], 0.06), and 24 of 61 are in first complete remission (CR1; probability of event-free survival [pEFS] at 4 years, 0.38; SE, 0.06). Twenty (35%) of 57 evaluable patients had >/=1,000 leukemic blasts per microliter of blood on day 8 of induction (defined as prednisone-poor-response [PPR]). These patients were older (10.0 v 6.88 years; P = .02) and had a higher WBC (144 v 29 x 10(9)/L; P = .0016) as compared with patients with prednisone good response (PGR; <1,000 blasts/microL at day 8). Only 2 of 20 patients (10%) with PPR remained in CR1 and alive: 6 patients with PPR did not survive after allogeneic bone marrow transplantation (BMT) due to recurring disease (n = 3) and toxicity (n = 3), and 12 nontransplanted patients died due to progression (n = 5) or relapse (n = 7). In contrast, 26 (70%) of the 37 patients with PGR are alive. Of 18 patients transplanted by allo-BMT, 1 relapsed (now in CR2) and 4 died after BMT. Among the 19 patients with PGR treated by chemotherapy alone, 8 remained in CR1 and 11 relapsed, of which 4 are in CR2 or CR3. The prednisone response emerged as the only independent prognostic factor for survival in Cox regression analysis. Thus, two thirds of Ph+ childhood ALL cases can be identified early by PGR, which, when treated with intensive BFM chemotherapy, with or without BMT, have a significantly lower risk of treatment failure. With a median continuous complete remission (CCR) time of 4.1 years, pEFS for PGR is 0.55 (SE, 0.08) compared with 0.10 (SE, 0.07) in patients with PPR (P = .0001). PGR is also an indicator for treatment responsiveness and durable second remission after relapse, which in turn may provide a second chance for BMT.

Adolescent↗

Consistent fusion of ZNF198 to the fibroblast growth factor receptor-1 in the t(8;13)(p11;q12) myeloproliferative syndrome.

The 8p11 myeloproliferative syndrome is a rare, aggressive condition associated with reciprocal translocations of chromosome band 8p11, most commonly the t(8;13)(p11;q12). To identify the genes involved in this translocation, we used fluorescence in situ hybridization (FISH) analysis to show that the chromosome 8 breakpoints fell within YAC 899e2 and that the chromosome 13 breakpoints are clustered in a region flanked by YACs 929f11 and 911h8. FISH using chromosome 13 PAC clones indicated that the t(8;13) is not simply a reciprocal translocation but also involves an inversion of 13q11-12. Exon trapping of a PAC that spanned the chromosome 13 translocation breakpoints led to the identification of a gene, ZNF198, that detected rearranged bands when used as a probe against Southern blots of patient DNA. Conceptual translation of the full-length ZNF198 cDNA sequence predicts a protein of 1377 amino acids that shows significant homology to the DXS6673E/KIAA0385 and KIAA0425 proteins. Alignment of these three proteins revealed a novel, conserved Zn-finger-related motif (MYM domain) of the general form CX2C19-22CX3CX13-19CX2CX19-25FCX3CX3F/Y that is repeated five times in each protein. To identify the translocation partner gene on chromosome 8, 5' and 3' RACE polymerase chain reactions (PCRs) were performed on patient RNA with several combinations of ZNF198 primers. Clones were identified in which the ZNF198 was fused to exon 9 of the fibroblast growth factor receptor-1 (FGFR1), a gene known to map to 8p11. An identical ZNF198-FGFR1 fusion was detected in the three patients with a t(8;13) for whom RNA was available; reciprocal FGFR1-ZNF198 transcripts were not detected. Rearrangements of both ZNF198 and FGFR1 were found in two further patients by Southern blotting. ZNF198-FGFR1 includes the five MYM domains of ZNF198 and the intracellular tyrosine kinase domain of FGFR1. We hypothesize that this fusion leads to constitutive activation of the FGFR1 tyrosine kinase in a manner analogous to the activation of ABL by BCR in chronic myeloid leukemia.

Amino Acid Sequence↗

Frequent loss of heterozygosity on the long arm of chromosome 6: identification of two distinct regions of deletion in childhood acute lymphoblastic leukemia.

Cytogenetic analysis of childhood acute lymphoblastic leukemia (ALL) identified nonrandom chromosomal abnormalities of the long arm of chromosome 6. Most of the alterations are deletions that are thought to be indicative of the presence of a tumor suppressor gene that is mutated on the remaining allele. These observations led us to consider whether 6q loss may contribute to the pathogenesis of childhood ALL. To define further a region containing this gene, we analyzed the loss of heterozygosity (LOH) of chromosome 6 in 113 primary ALL samples with matched normal DNA using 34 highly informative microsatellite markers. LOH was found in 17 (15%) samples at one or more of the loci, and partial or interstitial deletions of 6q were detected in 11 of these tumors. On the basis of these results, we performed a detailed deletional map and identified two distinct regions of deletion. The first region is flanked by D6S283 and D6S302 loci at 6q21-22. The second region is flanked by D6S275 and D6S283 loci at 6q21. Clinical analysis determined that LOH of 6q was demonstrated both in precursor-B cell ALLs (15 of 93; 16%) and in T cell ALLs (2 of 19; 11%). In addition, 19 patients have been studied at diagnosis and relapse; 18 showed the same 6q21-22 structural abnormality at relapse (normal, 16 patients; LOH, 2 patients) as their initial presentation, suggesting, albeit with a small patient sample size, that 6q21-22 deletions may be an initial event in leukemogenesis and may occur less frequently during the progression of childhood ALL. These data suggest the presence of putative tumor suppressor genes on chromosome arm 6q that are important in the development of both T and precursor-B childhood ALLs. Our map provides important information toward cloning putative ALL tumor suppressor genes.

Child↗

Congress Report: XIX symposium of the International Association for Comparative Research on Leukemia and Related Diseases, Mannheim/Heidelberg, Germany, July 13 - 18, 1997.

The XIX Symposium of the International Association for Comparative Research on Leukemia and Related Diseases (IACRLRD, President: Prof. Dr. R. Hehlmann) was held in Mannheim and Heidelberg, Germany, July 13 - 18, 1997. Comparative research in cancer was systematically established in the 1950s. Similarities in morphology, biology and pathology between animal and human leukemias and related diseases and the viral origin of a variety of animal leukemias and related diseases (lymphomas, sarcomas, breast tumors etc.) led to the concept that comparative research should promote the understanding of human leukemias and related diseases. In 1960 the World Health Organization inaugurated the establishment of a World Committee for Comparative Leukemia Research. The first symposium took place in Hannover, Germany, in 1963. After the fifth symposium in Padova, Italy, in 1971 the International Association for Comparative Research on Leukemia and Related Diseases (IACRLRD) was founded to complement the World Committee and to expand the international effort. The history of the symposium shows the evolution from a meeting on animal leukemia viruses into one dealing with viral and genetic aspects of human and animal leukemia and related diseases. The scientific evolution of the Abelson murine leukemia virus with its abl oncogene in the 1970s to what currently appears as the most reliable marker for human chronic myeloid leukemia is merely one example. Comparative research has reached a new dimension with the the recent advances in sequencing of the genomes of a variety of species and of humans. Many genes identified in the human genome and relevant for disease can be found in the genomes of animal species and even in the genomes of bacteria and of yeast. This reminds us that not just human and animal biology but also pathology must be regarded as a continuum of evolution and that much can be learned from comparing the genetic information of different species. Comparative genome research will allow conclusions to be drawn from principles recognized in animal species which are relevant to human diseases. It is likely that the application of comparative research to genome analysis will provide basic new insights in molecular medicine into the function of living beings for both animal species and humans. The current revolution in genomics is the latest phase in a rich history of medical progress related to the comparative approach. Meetings and organizations that have grown out of IACRLRD, include, at least to some extent: the Meeting of the International Human Retrovirology Association, the Gallo Lab Meeting , the Feline Retrovirus Meeting, the Cold Spring Habor Retrovirus Meeting, international and regional AIDS meetings, and many others. The XIX symposium in Mannheim included five memorial lectures, seven plenary sessions, 18 parallel sessions, two round table discussions and a public forum. In addition, six associated satellite symposia were held. The general meeting, attended by participants from 27 countries, integrated thematically contributions of genetic, cellular, and viral factors toward the development of leukemia and lymphoma and sought unifying concepts in leukemogenesis.

Animals↗