Leukemia
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Gastric low grade MALT lymphomas show a pattern of somatic mutations in their rearranged immunoglobulin genes, indicative of antigen selection. This provides evidence for antigen stimulation in the lymphomagenesis. Gastric diffuse large B cell lymphomas develop secondary to low grade MALT lymphoma or de novo. ⋯ One case showed bi-allelic VH gene rearrangements, which were non-functional due to extensive deletions. Antigen selection could not be demonstrated or excluded. Antigen selection is a common feature in most analysed primary diffuse large B cell lymphomas, although some heterogeneity in the mechanisms involved in the lymphomagenesis of gastric primary diffuse large B cell lymphomas has not been excluded entirely (case 4).
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Randomized Controlled Trial Multicenter Study Clinical Trial
Multicenter randomized phase II trial of idarubicin vs mitoxantrone, combined with VP-16 and cytarabine for induction/consolidation therapy, followed by a feasibility study of autologous peripheral blood stem cell transplantation in elderly patients with acute myeloid leukemia.
To compare the antileukemic efficacy of idarubicin and mitoxantrone in elderly patients with acute myeloid leukemia (AML) and to evaluate the feasibility of autologous transplantation using PBSC after consolidation in those with a good performance status, 160 patients (median age 69 years), with AML at diagnosis, 118 of them with de novo AML and 42 with AML secondary to myelodysplastic syndrome or toxic exposure (sAML), received induction treatment with idarubicin, 8 mg/m2/day or mitoxantrone, 7 mg/m2/day, on days 1, 3, and 5, both combined with VP-16, 100 mg/m2/day on days 1 to 3 and cytarabine (araC), 100 mg/m2/day, on days 1 to 7. G-CSF, 5 microg/kg/day, was administered after chemotherapy in patients aged more than 70 years. Patients in complete remission (CR) received one course of consolidation using the same schedule as for induction except the araC administration was shortened to 5 days. ⋯ We conclude that this regimen is well tolerated and has a good efficacy to induce CR, without a significant difference in efficacy and toxicity between idarubicin and mitoxantrone. Intensive postinduction, including transplantation, is feasible; however, this procedure did not seem to prevent early relapse in the majority of patients. Neither the high rate of CR nor consolidation nor transplant procedure in a selected group of patients did translate into improved DFS and/or survival.
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We report a patient with Philadelphia (Ph)-positive, BCR-ABL rearrangement positive, chronic myeloid leukemia (CML) with a prolonged chronic phase of 24 years who was first prescribed alpha-2 interferon 22 years after initial diagnosis. This therapy was tolerated poorly on account of thrombocytopenia, but an eventual major cytogenetic response was followed soon afterwards by transformation to terminal acute myeloid leukemia (AML). ⋯ PCR-based clonality studies using an X-chromosome-linked restriction fragment polymorphism within the phosphoglycerate kinase gene (PGK1) further showed that the Ph-negative blast cells had a different clonal origin from the Ph-positive clone of chronic phase. We suggest that cases of underlying Ph-negative leukemic transformation in Ph-positive CML warrant further study and should be considered for trial of intensive remission induction therapy as appropriate for acute leukemia.
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Onconase is a 12 kDa protein homologous to pancreatic RNase A isolated from amphibian oocytes which shows cytostatic and cytotoxic activity in vitro, inhibits growth of tumors in mice and is in phase III clinical trials. The present study was aimed to reveal mechanisms by which onconase perturbs the cell cycle progression. ⋯ Cell incubation with 170 nM onconase for 24 h and longer led to their arrest in G1 which was accompanied by a decrease in expression of cyclin D3, no change in cyclin E, and enhanced expression of all three CKIs. pRb was underphosphorylated in the onconase arrested G1 cells but was phosphorylated in the cells that were still progressing through S and G2/M in the presence of onconase. The cytostatic effect of onconase thus appears to be mediated by downregulation of cyclin D3 combined with upregulation of p27KIP1, p16INK4A and p21WAF1/CIP1, the events which may prevent phosphorylation of pRb during G0/1 and result in cell arrest at the restriction point controlled by Cdk4/6 and D type cyclins.