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Defects in the control of Wnt signaling have emerged as a recurrent mechanism involved in cancer pathogenesis and acute myeloid leukaemia (AML), including the hematopoietic regeneration-associated WNT10B in AC133 bright leukaemia cells, although the existence of a specific mechanism remains unproven. We have obtained evidences for a recurrent rearrangement, which involved the WNT10B locus (WNT10B R ) within intron 1 (IVS1) and flanked at the 5' by non-human sequences whose origin remains to be elucidated; it also expressed a transcript variant (WNT10B IVS1 ) which was mainly detected in a cohort of patients with intermediate/unfavorable risk AML. We also identified in two separate cases, affected by AML and breast cancer respectively, a genomic transposable short form of human WNT10B (ht-WNT10B). The intronless ht-WNT10B resembles a long non-coding RNA (lncRNA), which suggests its involvement in a non-random microhomology-mediated recombination generating the rearranged WNT10B R . Furthermore, our studies supports an autocrine activation primed by the formation of WNT10B-FZD4/5 complexes in the breast cancer MCF7 cells that express the WNT10B IVS1 . Chemical interference of WNT-ligands production by the porcupine inhibitor IWP-2 achieved a dose-dependent suppression of the WNT10B-FZD4/5 interactions. These results present the first evidence for a recurrent rearrangement promoted by a mobile ht-WNT10B oncogene, as a relevant mechanism for Wnt involvement in human cancer.

Antifungal therapy may be unable to eradicate invasive mycosis in leukemia patients. The presence of persisting pulmonary nodules owing to mycosis seems to increase the risk of fungal relapse after chemotherapy and transplant procedures. Between 1997 and 2004, 10 acute leukemia patients underwent pulmonary surgery for invasive mycosis. The median time from diagnosis of mycosis to surgery was 135 days (range 21-147). Three patients underwent emergency surgery, owing to hemoptysis. In the other seven patients with nodule/cavitation remaining after antifungal treatment, surgery (three wedge resections, four lobectomies) was scheduled before transplant. Pathologic examination confirmed two aspergillosis and three zygomycosis. The only side effect was pneumothorax in one case. Nine patients were considered cured. Six patients underwent bone marrow transplantation (three allogeneic, three autologous) with antifungal prophylaxis without relapse during the transplant procedure. In selected patients scheduled for bone marrow transplantation, surgical resection of localized pulmonary fungus nodules combined with antifungal prophylaxis seem to be an effective treatment for preventing mycotic relapse.

Systematic data on the ability of pegfilgrastim to mobilize stem cells after chemotherapy are scarce. We evaluated the efficacy of a single 6 mg dose of pegfilgrastim for mobilizing peripheral blood stem cells (PBSC) in aggressive lymphoma patients. Between July 2004 and October 2005, 17 aggressive non-Hodgkin's lymphoma and 11 poor-risk Hodgkin's lymphoma were treated with cycles containing cisplatin-aracytin. At the end of chemotherapy, the patients received 6 mg of pegfilgrastim. Duration of grade 4 neutropenia, adverse events, time to neutrophil recovery, peak and harvest of CD34+ cells were recorded. Twenty-seven out of 28 patients harvested a median of 17.3 x 10(6)/CD34+ cells (range 2.5-28.9) after a median of 9 days (range 8-12 days), with a single apheresis procedure in 25 cases. All patients had grade 3-4 neutropenia, median duration 3 days. The only adverse event was mild bone pain. To date, 13 patients have been autografted with a median of 15.4 x 10(6) CD34+ pegfilgrastim-mobilized cells per kg (range 2.5-28.9) with rapid and sustained engraftment. Mobilization, harvesting and autografting of pegfilgrastim-mobilized PBC can be successfully achieved in pretreated patients with aggressive lymphoma., (Published online 31 July 2006.)

Mutations of the c-kit gene have been reported in myeloproliferative disorders. We describe here a case of Ph+ (b2a2) chronic myelogenous leukemia that, during the course of disease, showed an unusual bone marrow mast-cell infiltration. A mutational screening for the c-kit gene, performed on DNA routinely cryopreserved during the follow-up, evidenced the D816Y-activating mutation as an additional genetic abnormality. Treatment with imatinib mesylate resulted in a substantial decrease of the BCR-ABL/ABL ratio and in the absence of c-kit mutation. It is likely that the superimposed c-kit mutation, in this case, may account for the transient bone marrow mastocytosis.

The aim of our study was to evaluate the impact of an early intensification programme including chemotherapy (CHT), autologous stem cell transplantation (ASCT) and radiation therapy (RT) in patients with primary mediastinal large B cell lymphoma (MLCL) with sclerosis presenting with adverse prognostic factors. Between 1993 and 1999, 19 patients with MLCL were referred to our institution. Four patients were classified as low risk according to the age-adjusted International Prognostic Index (AA-IPI). Fifteen (79%) were categorised in the high-intermediate or high risk group and were considered eligible for ASCT. Induction therapy consisted of VACOP-B (etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone and bleomycin) for 12 weeks. After induction therapy the four low risk patients achieved a complete remission (CR) and did not undergo ASCT. Of the 15 poor risk patients, five achieved CR, seven partial remission (PR), and three showed refractory disease (RD). All these patients received mobilising therapy consisting of high-dose cyclophosphamide. After peripheral stem cell (PSC) collection, to obtain a greater tumor mass reduction before transplantation, the seven patients in PR underwent further treatment with high-dose etoposide and those with RD received two cycles of DHAP (dexamethasone, cytarabine and cisplatin). At the time of ASCT, seven patients were in CR, six in PR and two had RD. After transplantation using BEAM as preparative regimen, all patients but one achieved a CR. Seven patients with minimal (<25%) residual mass at computed tomography scan received further mediastinal RT even if they had a negative Ga(67) scan. At a median follow-up of 35 months from transplantation the disease free survival is 93%. The outcome following this programme of early intensification in poor prognosis MLCL results in a high incidence of durable remissions even in patients with refractory disease.

DCEP (dexamethasone, cyclophosphamide, etoposide, and cisplatin) has proved to be an effective salvage therapy for refractory-relapsed MM patients. Little is known, however, about its potential as mobilizing therapy. The aim of this study was to evaluate the efficacy of DCEP in mobilizing PBSC and to define its toxicity. Fifty-five MM patients received DCEP followed by G-CSF as part of high-dose programs including autologous transplantation. At the time of mobilization, 40 patients had previously received VAD only, and 15 alkylating agents. Mobilization was successful (minimum number of CD34(+) cells 2 x 10(6)/kg) in 48/55 patients (87%), and 41/55 patients (75%) collected >4 x 10(6)/kg CD34(+) cells. Of the seven patients who did not mobilize stem cells, five (71%) had been previously exposed to alkylating agents. The median number of CD34(+) cells harvested was 5.8 x 10(6)/kg (range 2.1-22.4). There was no treatment-related mortality. The side-effects of DCEP were always tolerable. No neutropenia <1000/microl nor thrombocytopenia <50,000/microl were observed. No patient required transfusion as a consequence of therapy, or hospitalization for septic complications. In conclusion, DCEP, in addition to its demonstrated anti-tumor activity, is an effective regimen for mobilizing peripheral blood progenitor cells in myeloma patients, with little or no side-effects. These properties render DCEP a useful regimen for the debulking and mobilization phase of high-dose programs for multiple myeloma.

A 48-year-old woman underwent allogeneic BMT for CML in chronic phase. One day +180 she experienced fever (37.8 degrees C) and skin rash. Blood cultures from the Hickman catheter and peripheral veins were positive for Saccharomyces cerevisiae. The clinical course of this patient indicates that Saccharomyces should be considered as a possible cause of fever of otherwise unknown origin.