Giovanna Meloni

Distinctive microRNA signature of acute myeloid leukemia bearing cytoplasmic mutated nucleophosmin

Acute myeloid leukemia (AML) carrying NPM1 mutations and cytoplasmic nucleophosmin (NPMc+ AML) accounts for about one-third of adult AML and shows distinct features, including a unique gene expression profile. MicroRNAs (miRNAs) are small noncoding RNAs of 19–25 nucleotides in length that have been linked to the development of cancer. Here, we investigated the role of miRNAs in the biology of NPMc+ AML. The miRNA expression was evaluated in 85 adult de novo AML patients characterized for subcellular localization/mutation status of NPM1 and FLT3 mutations using a custom microarray platform. Data were analyzed by using univariate t test within BRB tools. We identified a strong miRNA signature that distinguishes NPMc+ mutated (n = 55) from the cytoplasmic-negative (NPM1 unmutated) cases (n = 30) and includes the up-regulation of miR-10a, miR-10b, several let-7 and miR-29 family members. Many of the down-regulated miRNAs including miR-204 and miR-128a are predicted to target several HOX genes. Indeed, we confirmed that miR-204 targets HOXA10 and MEIS1, suggesting that the HOX up-regulation observed in NPMc+ AML may be due in part by loss of HOX regulators-miRNAs. FLT3-ITD+ samples were characterized by up-regulation of miR-155. Further experiments demonstrated that the up-regulation of miR-155 was independent from FLT3 signaling. Our results identify a unique miRNA signature associated with NPMc+ AML and provide evidence that support a role for miRNAs in the regulation of HOX genes in this leukemia subtype. Moreover, we found that miR-155 was strongly but independently associated with FLT3-ITD mutations.

Results from a randomized trial of salvage chemotherapy followed by lestaurtinib for patients with FLT3 mutant AML in first relapse

In a randomized trial of therapy for FMS-like tyrosine kinase-3 (FLT3) mutant acute myeloid leukemia in first relapse, 224 patients received chemotherapy alone or followed by 80 mg of the FLT3 inhibitor lestaurtinib twice daily. Endpoints included complete remission or complete remission with incomplete platelet recovery (CR/CRp), overall survival, safety, and tolerability. Correlative studies included pharmacokinetics and analysis of in vivo FLT3 inhibition. There were 29 patients with CR/CRp in the lestaurtinib arm and 23 in the control arm (26% vs 21%; P = .35), and no difference in overall survival between the 2 arms. There was evidence of toxicity in the lestaurtinib-treated patients, particularly those with plasma levels in excess of 20 μM. In the lestaurtinib arm, FLT3 inhibition was highly correlated with remission rate, but target inhibition on day 15 was achieved in only 58% of patients receiving lestaurtinib. Given that such a small proportion of patients on this trial achieved sustained FLT3 inhibition in vivo, any conclusions regarding the efficacy of combining FLT3 inhibition with chemotherapy are limited. Overall, lestaurtinib treatment after chemotherapy did not increase response rates or prolong survival of patients with FLT3 mutant acute myeloid leukemia in first relapse. This study is registered at www.clinicaltrials.gov as #NCT00079482.

Molecular evaluation of residual disease as a predictor of relapse in acute promyelocytic leukaemia.

Acute promyelocytic leukaemia (APL) is characterised by a unique fusion transcript, PML/RAR alpha. We tested for this transcript in 35 APL patients who were in apparent remission after various treatments. 11 of 13 patients who tested positive 4 months after achieving remission were in relapse 1-4 months later. All 22 patients who tested negative at 4 months were disease-free after a further 3 months to five years. The test may therefore prove useful in determining the need for additional treatment during clinical remission.

Haematopoietic stem cell transplantation for patients with myelo- dysplastic syndromes and secondary acute myeloid leukaemias: a report on behalf of the Chronic Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)

Allogeneic stem cell transplantation from an HLA‐identical sibling donor is a curative treatment option for a young patient with myelodysplastic syndrome, limited by age and lack of sibling donors. Alternative stem cell sources have been used more recently, such as unrelated donors, non‐identical family members or autologous transplants. This analysis of 1378 transplants reported to the European Group for Blood and Marrow Transplantation (EBMT) addresses the outcome of the varying procedures according to the known risk factors. The estimated disease‐free survival (DFS) and estimated relapse risk at 3 years were both 36% for 885 patients transplanted with stem cells from matched siblings. In the multivariate analysis, age and stage of disease had independent prognostic significance for DFS, survival and treatment‐related mortality. Patients transplanted at an early stage of disease had a significantly lower risk of relapse than patients transplanted at more advanced stages. The estimated DFS at 3 years was 25% for the 198 patients with voluntary unrelated donors, 28% for the 91 patients with alternative family donors and 33% for the 126 patients autografted in first complete remission. The non‐relapse mortality was 58% for patients with unrelated donors, 66% for patients with non‐identical family donors and 25% for autografted patients. The relapse rate of 18% was relatively low for patients with non‐identical family donors, 41% for patients with unrelated donors and 55% for patients treated with autologous stem cell transplantation. Both allogeneic and autologous stem cell transplantation have emerged as treatment options for patients with myelodysplastic syndromes. Transplantation with an HLA‐identical sibling donor is the preferred treatment option. Patients without an HLA‐identical sibling donor may be treated with either autologous stem cell transplantation or an alternative donor transplantation. Patients younger than 20 years may be treated with an unrelated donor transplantation. Patients older than 40 years, and probably also patients between 20 and 40 years, may benefit most from an autologous stem cell transplantation.

Dasatinib as first-line treatment for adult patients with Philadelphia chromosome-positive acute lymphoblastic leukemia

Dasatinib is a potent BCR-ABL inhibitor effective in chronic myeloid leukemia and Ph(+) acute lymphoblastic leukemia (ALL) resistant/intolerant to imatinib. In the GIMEMA LAL1205 protocol, patients with newly diagnosed Ph(+) ALL older than 18 years (with no upper age limit) received dasatinib induction therapy for 84 days combined with steroids for the first 32 days and intrathecal chemotherapy. Postremission therapy was free. Fifty-three patients were evaluable (median age, 53.6 years). All patients achieved a complete hematologic remission (CHR), 49 (92.5%) at day 22. At this time point, 10 patients achieved a BCR-ABL reduction to < 10(-3). At 20 months, the overall survival was 69.2% and disease-free survival was 51.1%. A significant difference in DFS was observed between patients who showed at day 22 a decrease in BCR-ABL levels to < 10(-3) compared with patients who never reached these levels during induction. In multivariate analysis, BCR-ABL levels of < 10(-3) at day 85 correlated with disease-free survival. No deaths or relapses occurred during induction. Twenty-three patients relapsed after completing induction. A T315I mutation was detected in 12 of 17 relapsed cases. Treatment was well tolerated; only 4 patients discontinued therapy during the last phase of the induction when already in CHR. In adult Ph(+) ALL, induction treatment with dasatinib plus steroids is associated with a CHR in virtually all patients, irrespective of age, good compliance, no deaths, and a very rapid debulking of the neoplastic clone.

Secondary leukaemia and myelodysplasia after autografting for lymphoma: results from the EBMT

Between 1978 and 1996 more than 7500 lymphoma transplants have been reported to the European Bone Marrow Transplantation (EBMT) Lymphoma Registry. This has been examined to establish the incidence of secondary leukaemia and myelodysplasia and to relate this to possible prognostic factors. 131 centres representing 4998 patients responded to a questionnaire. This identified 66 patients with post transplant myelodysplastic syndrome (MDS)/acute myeloid leukaemia (AML). The actuarial risk for MDS/AML at 5 years post‐transplant (±95% CI) was 4.6% (3.1–6.8) for Hodgkins disease and 3.0% (2.0–4.3) for non‐Hodgkins lymphoma. Multivariate analysis for all patients demonstrated an effect of age at transplant, radiotherapy at conditioning, number of transplants and interval between diagnosis and transplant as risk factors. For patients with NHL, grade of histology was important (low grade  >  intermediate or high‐grade); for Hodgkins disease, female sex was identified as a risk factor. These findings suggest that the incidence of MDS/AML may not be greater following an autograft than after conventional chemotherapy.

Neutropenic Enterocolitis in Patients With Acute Leukemia: Prognostic Significance of Bowel Wall Thickening Detected by Ultrasonography

PURPOSE Neutropenic enterocolitis (NE) is a severe complication of intensive chemotherapy and is barely identifiable by clinical signs alone. Ultrasonography (US) supports the diagnosis of NE by showing pathologic thickening of the bowel wall. The aim of this study was to evaluate the prognostic value of the degree of mural thickening evaluated by US in patients with clinically suspected NE. PATIENTS AND METHODS Neutropenic patients with fever, diarrhea, and abdominal pain after intensive chemotherapy for hematologic malignancies were studied with abdominal US. We evaluated the degree of bowel wall thickening detected by US and its correlation with the duration of the clinical syndrome as well as NE-related mortality. RESULTS Eighty-eight (6%) of 1,450 consecutive patients treated for leukemia had clinical signs of NE. In 44 (50%) of 88 patients, US revealed pathologic wall thickening (mean +/- SD, 10.2 +/- 2.9 mm; range, 6 to 18). The mean duration of symptoms was significantly longer in this group (7.9 days) than among patients without mural thickening (3.8 days, P <.0001), and the NE-related mortality rate was higher (29.5% v 0%, P <.001). Patients with bowel wall thickness of more than 10 mm had a significantly higher mortality rate (60%) than did those with bowel wall thickness < or = 10 mm (4.2%, P <.001). CONCLUSION Symptomatic patients with sonographically detected bowel wall thickening have a poor prognosis compared with patients without this finding. In addition, mural thickness of more than 10 mm is associated with poorer outcome among patients with NE.

Early Autologous Stem-Cell Transplantation Versus Conventional Chemotherapy as Front-Line Therapy in High-Risk, Aggressive Non-Hodgkin’s Lymphoma: An Italian Multicenter Randomized Trial

PURPOSE To evaluate the role of early intensification with high-dose therapy (HDT) and autologous stem-cell transplantation (ASCT) as front-line chemotherapy for patients with high-risk, histologically aggressive non-Hodgkins lymphoma (NHL). PATIENTS AND METHODS We planned a multicenter, randomized trial to compare a conventional chemotherapy regimen of methotrexate with leucovorin rescue, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B; arm A) with an abbreviated regimen of MACOP-B (8 weeks) followed by HDT and ASCT (arm B) for intermediate-high-risk/high-risk patients (according to the age-adjusted International Prognostic Index). From September 1994 to April 1998, 150 patients with aggressive lymphoma were enrolled onto the trial. Seventy-five patients were randomly assigned to arm A and 75 patients were randomly assigned to arm B. In both arms, involved-field radiation therapy (36 Gy) was delivered to the site of bulky disease. RESULTS The rate of complete response was 68% in arm A and 76% in arm B (P = not significant [NS]). Three toxic deaths (4%) occurred in arm B and one (1%) occurred in arm A (P = NS). In arm B, 30 patients (40%) did not undergo HDT and ASCT. According to the intention-to-treat analysis at a median follow-up of 24 months, 5-year overall survival probability in arms A and B was 65% and 64% (P =.95), 5-year progression-free survival was 49% and 61% (P =.21), and 5-year relapse-free survival was 65% and 77% (P =.22), respectively. CONCLUSION Abbreviated chemotherapy followed by intensification with HDT-ASCT is not superior to conventional chemotherapy in patients with high-risk, aggressive NHL. Additional randomized trials will clarify whether HDT-ASCT as front-line therapy after a complete course of conventional chemotherapy improves survival in this group of patients.

Daunorubicin versus mitoxantrone versus idarubicin as induction and consolidation chemotherapy for adults with acute myeloid leukemia: the EORTC and GIMEMA groups study AML-10

PURPOSE To compare the antitumor efficacy of three different anthracyclines in combination with cytarabine and etoposide in adult patients with newly diagnosed acute myeloid leukemia (AML). PATIENTS AND METHODS We randomly assigned 2,157 patients (age range, 15 to 60 years) to receive intensive induction-consolidation chemotherapy containing either daunorubicin, idarubicin, or mitoxantrone. After achieving complete remission (CR), patients were assigned to undergo either allogeneic or autologous stem-cell transplantation (SCT), depending on the availability of a sibling donor. RESULTS The overall CR rate (69%) was similar in the three groups. Autologous SCT was performed in 37% of cases in the daunorubicin arm versus only 29% and 31% in mitoxantrone and idarubicin, respectively (P < .001). However, the disease-free survival (DFS) and survival from CR were significantly shorter in the daunorubicin arm: the 5-year DFS was 29% versus 37% and 37% in mitoxantrone and idarubicin, respectively. The proportion of patients who underwent allogeneic SCT (22%) was equivalent in the three treatment groups, and the outcome was similar as well. The [corrected] 5-year overall survival rates were 31%, 34%, and 34%, [corrected] respectively. CONCLUSION In adult patients with AML who do not receive an allogeneic SCT, the use of mitoxantrone or idarubicin instead of daunorubicin enhances the long-term efficacy of chemotherapy.

Mitoxantrone, etoposide, and intermediate-dose cytarabine: an effective and tolerable regimen for the treatment of refractory acute myeloid leukemia.

Thirty-two patients with refractory acute myeloid leukemia (AML) received salvage therapy with a single course of mitoxantrone 6 mg/m2 intravenous (IV) bolus, etoposide 80 mg/m2 IV for a period of 1 hour, and cytarabine (Ara-C) 1 g/m2 IV for a period of 6 hours daily for 6 days (MEC). Eighteen patients were primarily resistant to conventional daunorubicin and Ara-C induction treatment; eight patients had relapsed within 6 months from initial remission; six patients had relapsed after a bone marrow transplantation (BMT) procedure. Overall, 21 patients (66%) achieved a complete remission (CR), two (6%) died of infection during induction, and nine (28%) had resistant disease. Age greater than 50 years was the only factor predictive for a significantly lower response rate (P = .03). The median remission duration was 16 weeks; the overall median survival was 36 weeks. Severe myelosuppression was observed in all patients resulting in fever or documented infections in 91% of patients. Nonhematologic toxicity was minimal. We conclude that the MEC regimen has significant antileukemic activity and acceptable toxicity in salvage AML. Its benefit in front-line AML therapy is being investigated.