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Eosinophilia is common in myeloproliferative disorders (MPDs) with abnormalities of chromosome band 5q31-33, including those that present with t(1; 5)(q23;q33). With the development of rational drug therapy, characterization of the molecular targets for these translocations could guide treatment and affect patient survival. We cloned the t(1; 5)(q23;q33) and showed that it fuses platelet-derived growth factor receptor beta (PDGFRB) to the coiled-coil domains of a novel partner protein, myomegalin. Using two-color interphase fluorescence in situ hybridization (FISH), we also demonstrated that the eosinophils are clonal in these disorders. Imatinib mesylate has recently been shown to be efficacious in MPDs with PDGFR activation. Therefore, following our molecular studies, we were able to redirect this patient's treatment. Although she had refractory and progressive disease, once imatinib was started, complete clinical and hematologic remission, as well as major cytogenetic response, was achieved. Given the therapeutic implications, our findings stress the need to aggressively investigate the molecular basis of these diseases, with emphasis on the PDGFR family. IntroductionThe cloning of genes affected by recurrent chromosomal translocations has furthered our understanding of the molecular basis of hematologic malignancies and allowed the development of molecular assays that have improved diagnosis and monitoring of therapy. It has also led to the development of rational targeted drug therapy, including the specific tyrosine kinase inhibitor, imatinib mesylate 1 (Gleevec; Novartis, Basel, Switzerland).Eosinophilia is common in several myeloproliferative disorders (MPDs), notably chronic myeloid leukemia (CML) and the 8p11 myeloproliferative syndrome. 2,3 Less common causes of eosinophilia include MPDs associated with translocations that involve chromosome band 5q31-33. 4 Cloning of these translocations 4-9 showed that they consistently target the PDGFRB gene. In all cases, partner genes contribute oligomerization domains that constitutively activate the tyrosine kinase of plateletderived growth factor receptor beta (PDGFRB). Recently, cryptic deletions of chromosome 4q12 resulting in activation of PDGFRA were found in cases of hypereosinophilic syndrome (HES), 10 suggesting that activation of the PDGFR receptor tyrosine kinase family is a common theme in this phenotypically similar collection of disorders.Of the MPDs with eosinophilia, one unique subgroup presents with a t(1;5)(q23;q33). 11,12 Here, we describe the molecular cloning of this translocation and the clinical/ translational consequences of this finding. Study designAn 11-month-old girl presented with malaise, poor feeding, and hepatosplenomegaly. The initial blood count was hemoglobin (Hb) 60 g/L (6.0 g/dL), white blood cell (WBC) count 43.9 ϫ 10 9 /L with a neutrophilic left shift, marked eosinophilia, monocytosis, and thrombocytopenia. After a bone marrow examination, the diagnosis of an myelodysplastic syndrome (MDS)/MPD syndrome with eosinophilia w...

Preoperative intraarterial (IA) cisplatin (CDP) was administered to 92 patients with nonmetastatic osteosarcoma. The ages of the patients ranged from 4 to 28 years. Sixty-four patients (70%) received 2 or 3 preoperative courses and 28 (30%) received 4 or more. Sixty-two specimens were available for pathologic examination to assess the degree of tumor necrosis. More than 90% tumor destruction was observed in 16 of 42 patients (38%) who received 1 to 3 preoperative courses as opposed to 17 of 20 (85%) who received 4 or more courses. Patients who received 4 or more courses had a 2-fold probability of achieving more than 90% tumor necrosis, and 68% underwent conservative surgery. Of those who received 3 or less courses, 23% underwent conservative surgery. Postoperatively, patients were treated with intravenous (IV) CDP alternating with doxorubicin (ADR) (Adriamycin, Adria Laboratories, Columbus, OH). Pulmonary metastases developed in 36 patients, bone metastases in 2, and local recurrence in 6. Two patients died of cardiac failure without evidence of disease. Thus, 46 patients (50%) were continuously free of disease 18 to 78 months after diagnosis. Univariate and multivariate analyses showed that male sex, low grade preoperative chemotherapy-induced necrosis, and nonosteoblastic histologic condition were prognostic factors predictive of recurrence, while male sex and large tumor size were prognostic factors predictive of death. These results are comparable with those reported by other centers and are superior to our previous experiences that yielded survival rates of 5% to 10%. A substantial number of patients also had the opportunity to achieve tumor removal with conservative surgery.

PURPOSE To describe event-free survival (EFS) and toxicities in children with low-risk acute lymphoblastic leukemia (ALL) assigned to receive either continuous 6-mercaptopurine (6-MP) and weekly methotrexate (MTX) or intermittent 6-MP with intermediate-dose MTX, as maintenance treatment. PATIENTS AND METHODS Between October 1, 2000, and December 31, 2007, 635 patients with low-risk ALL were enrolled onto Brazilian Childhood Cooperative Group for ALL Treatment (GBTLI) ALL-99 protocol. Eligible children (n = 544) were randomly allocated to receive either continuous 6-MP/MTX (group 1, n = 272) or intermittent 6-MP (100 mg/m(2)/d for 10 days, with 11 days resting) and MTX (200 mg/m(2) every 3 weeks; group 2, n = 272). RESULTS The 5-year overall survival (OS) and EFS were 92.5% +/- 1.5% SE and 83.6% +/- 2.1% SE, respectively. According to maintenance regimen, the OS was 91.4% +/- 2.2% SE (group 1) and 93.6% +/- 2.1% SE (group 2; P = .28) and EFS 80.9% +/- 3.2% SE (group 1) and 86.5% +/- 2.8% SE (group 2; P = .089). Remarkably, the intermittent regimen led to significantly higher EFS among boys (85.7% v 74.9% SE; P = .027), while no difference was seen for girls (87.0% v 88.8% SE; P = .78). Toxic episodes were recorded in 226 and 237 children, respectively. Grade 3 to 4 toxic events for groups 1 and 2 were, respectively, 273 and 166 for hepatic dysfunction (P = .002), and 772 and 636 for hematologic episodes (P = .005). Deaths on maintenance were: seven (group 1) and one (group 2). CONCLUSION The intermittent use of 6-MP and MTX in maintenance is a less toxic regimen, with a trend toward better long-term EFS. Boys treated with the intermittent schedule had significantly better EFS.

During the past 35 years, survival rates for children with extracranial malignant germ cell tumors (GCTs) have increased significantly. Success has been achieved primarily through the application of platinum-based chemotherapy regimens; however, clinical challenges in GCTs remain. Excellent outcomes are not distributed uniformly across the heterogeneous distribution of age, histologic features, and primary tumor site. Despite good outcomes overall, the likelihood of a cure for certain sites and histologic conditions is less than 50%. In addition, there are considerable long-term treatment-related effects for survivors. Even modest cisplatin dosing can cause significant long-term morbidities. A particular challenge in designing new therapies for GCT is that a variety of specialists use different risk stratifications, staging systems, and treatment approaches for three distinct age groups (childhood, adolescence, and young adulthood). Traditionally, pediatric cancer patients younger than 15 years have been treated by pediatric oncologists in collaboration with their surgical specialty colleagues. Adolescents and young adults with GCTs often are treated by medical oncologists, urologists, or gynecologic oncologists. The therapeutic dilemma for all is how to best define disease risk so that therapy and toxicity can be appropriately reduced for some patients and intensified for others. Further clinical and biologic insights can only be achieved through collaborations that do not set limitations by age, sex, and primary tumor site. Therefore, international collaborations, spanning different cooperative groups and disciplines, have been developed to address these challenges.

Osteosarcoma (OS) is the most common primary bone cancer in childhood. OS is an aggressive disease, and metastatic patients evolve with very poor clinical outcomes. Genetically, OSs are extremely complex tumors, and the related metastatic process is not well understood in terms of the biology of the disease. In this context, long non-coding RNAs (lncRNAs) have emerged as an important class of gene expression regulators that play key roles in the invasion and metastasis of several human tumors. Here, we evaluated the expression of HULC, which is an lncRNA that is associated with the tumor metastatic process, and assessed its potential role as a prognostic marker in OS. HULC expression was evaluated in primary OS samples using real-time RT-PCR. HULC expression status was determined by receiver operating characteristic (ROC) analysis, and its association with survival was assessed using the Kaplan-Meier method. The HULC expression level was not significantly associated with the clinicopathological characteristics of the OS patients. However, our data demonstrated that higher levels of expression of HULC were associated with lower survival rates in OS patients, both in terms of overall and event-free survival. Elevated HULC expression was associated with poor clinical outcomes among the OS patients, which suggests that HULC could be a potential prognostic biomarker in OS.

Reduction of therapy to two drugs did not compromise survival outcomes for patients in the IR-GR group, and escalation of therapy with PEI did not significantly improve OS and EFS in patients at HR.

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