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The combination of azacitidine and donor lymphocyte infusions (DLI) as first salvage therapy for relapse after allogeneic transplantation (allo-HSCT) was studied in 30 patients with acute myeloid leukemia (AML; n=28) or myelodysplastic syndromes (MDS; n=2) within a prospective single-arm multicenter phase-II trial. Treatment schedule contained up to eight cycles azacitidine (100 mg/m(2)/day, days 1-5, every 28 days) followed by DLI (from 1-5 × 10(6) to 1-5 × 10(8) CD3(+)cells/kg) after every second azacitidine cycle. A median of three courses azacitidine (range 1-8) were administered, and 22 patients (73%) received DLI. Overall response rate was 30%, including seven complete remissions (CRs, 23%) and two partial remissions (7%). Five patients remain in CR for a median of 777 days (range 461-888). Patients with MDS or AML with myelodysplasia-related changes were more likely to respond (P=0.011), and a lower blast count (P=0.039) as well as high-risk cytogenetics (P=0.035) correlated with the likelihood to achieve CR. Incidence of acute and chronic graft-versus-host disease was 37% and 17%, respectively. Neutropenia and thrombocytopenia grade III/IV occurred during 65% and 63% of treatment cycles, while infections were the most common grade III/IV non-hematological toxicity. Azacitidine and DLI as salvage therapy is safe, induces long-term remissions and may become an alternative for patients with AML or MDS relapsing after allo-HSCT.

Patients suffering from high-risk myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML) secondary to MDS (sAML) are characterized by poor response to conventional cytotoxic chemotherapy. The purpose of our prospective single-center study was to examine the safety and efficacy of an allogeneic hematopoietic stem cell transplantation (HSCT) following a sequential conditioning regimen as first-line therapy for previously untreated patients with high-risk MDS or sAML. Between November 2003 and June 2010, 30 patients (20 high-risk MDS, 10 sAML) received fludarabine (4 × 30 mg/m(2)), amsacrine (4 × 100 mg/m(2)), and Ara-C (4 × 2 g/m(2), FLAMSA). After 2 to 3 days of rest, patients received high-dose melphalan alone (200 mg/m(2) for patients with an age <50 years, 150 mg/m(2) for patients with an age between 50 and 60 years, and 100 mg/m(2) for patients with an age >60 years; n = 24) or melphalan and thiotepa (10 mg/kg, Mel/Thio, n = 6). Following these high-dose conditioning regimens, a median number of 7.7 × 10(6) CD34(+) cells/kg body weight (range: 2.9 × 10(6)-17.2 × 10(6)) were transplanted from 13 related or 17 unrelated donors. Antithymocyte globulin (Fresenius 30-60 mg/kg) as well as tacrolimus and mycophenolate mofetil were used for graft-versus-host disease (GVHD) prophylaxis. All patients except 1 with primary graft failure achieved complete remission after HSCT. After a median follow-up time of 28 months (range: 7-81), 21 patients (70%) were alive and free of disease. Overall, 4 patients relapsed. At 2 years, overall survival, event-free survival, and treatment-related mortality were 70%, 63%, and 30%, respectively. Because of undue toxicity, thiotepa is no longer part of the conditioning regimen. Our results add to the body of evidence that a FLAMSA-based sequential conditioning therapy is effective for previously untreated patients with high-risk MDS or sAML., (Copyright © 2012. Published by Elsevier Inc.)

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy. Treatment of patients suffering from high-risk AML as defined by clinical parameters, cytogenetics, and/or molecular analyses is often unsuccessful. OSI-461 is a pro-apoptotic compound that has been proposed as a novel therapeutic option for patients suffering from solid tumors like prostate or colorectal carcinoma. But little is known about its anti-proliferative potential in AML. Hence, we treated bone marrow derived CD34(+) selected blast cells from 20 AML patients and the five AML cell lines KG-1a, THP-1, HL-60, U-937, and MV4-11 with the physiologically achievable concentration of 1 μM OSI-461 or equal amounts of DMSO as a control. Following incubation with OSI-461, we found a consistent induction of apoptosis and an accumulation of cells in the G2/M phase of the cell cycle. In addition, we demonstrate that the OSI-461 mediated anti-proliferative effects observed in AML are associated with the induction of the pro-apoptotic cytokine mda-7/IL-24 and activation of the growth arrest and DNA-damage inducible genes (GADD) 45α and 45γ. Furthermore, OSI-461 treated leukemia cells did not regain their proliferative potential for up to 8 days after cessation of treatment following the initial 48 h treatment period with 1 μM OSI-461. This indicates sufficient targeting of the leukemia-initiating cells in our in vitro experiments through OSI-461. The AML samples tested in this study included samples from patients who were resistant to conventional chemotherapy and/or had FLT3-ITD mutations demonstrating the high potential of OSI-461 in human AML.

Background: Few data are available on therapy-related myelodysplastic syndromes and acute myeloid leukemia developing after radioiodine treatment., Design and Methods: We retrospectively analyzed 39 patients with myeloid neoplasms following radioiodine treatment, whose data were reported to the Duesseldorf Myelodysplastic Syndromes Register (8 of 3814 patients) and five other German Myelodysplastic Syndromes centers (n=31) between 1982 and 2011. These data were compared with those from 165 patients from our Myelodysplastic Syndromes Register with therapy-related myeloid neoplasms following chemotherapy (n=90), radiation (n=30), or radiochemotherapy (n=45)., Results: With a median latency of 79 months, 18 patients developed therapy-related acute myeloid leukemia and 21 presented with therapy-related myelodysplastic syndromes (8 refractory anemia with excess blasts I/II, 6 refractory anemia with multilineage dysplasia, 3 myelodysplastic syndromes with del(5q), 1 refractory anemia, 1 refractory anemia with ring sideroblasts, 1 chronic myelomonocytic leukemia II, 1 myelodysplastic/myeloproliferative neoplasm unclassifiable). Risk assessment according to the International Prognostic Scoring System was low-risk in 23%, intermediate-1 in 29%, intermediate-2 in 35%, and high-risk in 13%. Karyotype was abnormal in 68%, with chromosomes 7 (30%), 5 (26%), 8 (26%) and 3 (17%) being most frequently affected. No differences in the distribution of gender, World Health Organization subtype, acute myeloid leukemia progression, International Prognostic Scoring System score, and cytogenetic risk were observed between patients with therapy-related myeloid neoplasms following radioiodine or other treatment modalities. Of 17 patients who received induction chemotherapy, 71% were refractory to this treatment or died from treatment-related toxicity. The median overall survival in the entire group was 21.7 months (95%-CI 10.5-33 months) and did not differ significantly in comparison to the survival of patients with therapy-related myeloid neoplasms following other cytotoxic treatments. Patients with therapy-related acute myeloid leukemia had significantly inferior overall survival (12.4 versus 28.7 months, P=0.002)., Conclusions: Patients developing a therapy-related myeloid neoplasm after radioiodine treatment usually present with biological characteristics similar to those seen in patients with therapy-related myeloid neoplasms following other cytotoxic treatment modalities, associated with a low response rate to induction chemotherapy and poor prognosis.

Acute myeloid leukemia is a heterogeneous disease with varying genetic and molecular pathologies. Non-steroidal anti-inflammatory drugs (NSAIDs) have been proven to possess significant anti-proliferative potential in various cancer cells in vitro and in vivo. Hence, treatment with these agents can be utilized to study disease specific anti-proliferative pathways. In this study, a total number of 42 bone marrow derived CD34(+) selected de novo AML patient samples and the AML cell lines THP-1 and HL-60 were treated with the NSAIDs Sulindac sulfide and Diclofenac. We analyzed viability, apoptosis, differentiation and addressed the molecular mechanisms involved. We found a consistent induction of apoptosis and to some extent an increased myeloid differentiation capacity in NSAID treated AML cells. Comprehensive protein and gene expression profiling of Diclofenac treated AML cells revealed transcriptional activation of GADD45α and its downstream MAPK/JNK pathway as well as increased protein levels of the caspase-3 precursor. This pointed towards a role of the c-Jun NH(2)-terminal kinase (JNK) in NSAID mediated apoptosis that we found indeed to be dependent on JNK activity as addition of a specific JNK-inhibitor abrogated apoptosis. Furthermore, the AP-1 transcription factor family members' c-Jun, JunB and Fra-2 were transcriptionally activated in NSAID treated AML cells and re-expression of these transcription factors led to activation of GADD45α with induction of apoptosis. Mechanistically, we demonstrate that NSAIDs induce apoptosis in AML through a novel pathway involving increased expression of AP-1 heterodimers, which by itself is sufficient to induce GADD45α expression with consecutive activation of JNK and induction of apoptosis.

Patients with AML or myelodysplastic syndrome who relapse after allo-SCT have a poor prognosis. In the search for novel treatment strategies for these patients, we conducted a multicenter retrospective analysis and identified 22 patients treated with the DNA-methylation inhibitor 5-azacytidine (5-Aza). Patients received a median number of two cycles 5-Aza (range 1-8) at a dose of 100 mg/m(2) over 5 days following relapse. Eighteen patients (82%) also received a median number of two donor lymphocyte infusions (DLI, range 1-5). Sixteen patients (72%) responded to 5-Aza treatment and five patients (23%) achieved a CR. 5-Aza-induced CR lasted for 433 days (median, range 114-769). Median survival and the estimated 2-year survival rate were 144 days and 23%, respectively. Acute GVHD after DLI was seen in six patients (33%) and four of these patients developed chronic GVHD of the skin. There were no treatment-related deaths. Patients who achieved halving of leukocyte counts after the first 5-Aza cycle had a superior median survival of 802 days compared with 135 days (P=0.0025) in all other patients. On univariate analysis, the achievement of this halving of leukocyte counts was identified as a significant predictor of survival.

Thrombocytopenia is a frequent symptom and clinical challenge in patients with myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Eltrombopag is a small molecule thrombopoietin receptor agonist that might be a new option to treat thrombocytopenia in these diseases, provided that it does not stimulate malignant hematopoiesis. In this work, we studied the effects of Eltrombopag on proliferation, apoptosis, differentiation, colony formation, and malignant self-renewal of bone marrow mononuclear cells of patients with AML and MDS. Malignant bone marrow mononuclear cells did not show increased proliferation, or increased clonogenic capacity at concentrations of Eltrombopag ranging from 0.1 to 30 microg/mL. On the contrary, we observed a moderate, statistically nonsignificant (P = .18), decrease of numbers of malignant cells (mean, 56%; SD, 28%). Eltrombopag neither led to increased 5-bromo-2-deoxyuridine incorporation, decreased apoptosis, an increase of malignant self-renewal, nor enhanced in vivo engraftment in xenotransplantations. Furthermore, we found that Eltrombopag was capable of increasing megakaryocytic differentiation and formation of normal megakaryocytic colonies in patients with AML and MDS. These results provide a preclinical rationale for further testing of Eltrombopag for treatment of thrombocytopenia in AML and MDS.

The fms-related tyrosine kinase 3 internal tandem duplication (FLT3-ITD) can be found in about one quarter of patients with acute myeloid leukemia (AML) [Small D. FLT3 mutations: biology and treatment. Hematology Am Soc Hematology. Educ. Program 2006;178-84 [Review]]. Patients who carry this mutation have a high risk of relapse even after allogeneic stem cell transplantation [Sheikhha MH, Awan A, Tobal K, Liu Yin JA. Prognostic significance of FLT3 ITD and D835 mutations in AML patients. Hematol J 2003;4:41-6; Meshinchi S, Arceci RJ, Sanders JE, Smith FO, Woods WB, Radich JP, et al. Role of allogeneic stem cell transplantation in FLT3/ITD-positive AML. Blood 2006;108(1):400-1]. Recent reports show that Sorafenib, a multikinase inhibitor has significant activity against FLT3-ITD(+) blasts in vitro [Auclair D, Miller D, Yatsula V, Pickett W, Carter C, Chang Y, et al. Antitumor activity of sorafenib in FLT3-driven leukemic cells. Leukemia 2007;21(3):439-45]. We here report the first clinical case of molecular remission induced by Sorafenib in a patient with FLT3-ITD(+) AML and extramedullary disease after allogenic stem cell transplantation.

Knockdown of the transcription factor PU.1 (encoded by Sfpi1) leads to acute myeloid leukemia (AML) in mice. We examined the transcriptome of preleukemic hematopoietic stem cells (HSCs) in which PU.1 was knocked down (referred to as 'PU.1-knockdown HSCs') to identify transcriptional changes preceding malignant transformation. Transcription factors c-Jun and JunB were among the top-downregulated targets. Restoration of c-Jun expression in preleukemic cells rescued the PU.1 knockdown-initiated myelomonocytic differentiation block. Lentiviral restoration of JunB at the leukemic stage led to loss of leukemic self-renewal capacity and prevented leukemia in NOD-SCID mice into which leukemic PU.1-knockdown cells were transplanted. Examination of human individuals with AML confirmed the correlation between PU.1 and JunB downregulation. These results delineate a transcriptional pattern that precedes leukemic transformation in PU.1-knockdown HSCs and demonstrate that decreased levels of c-Jun and JunB contribute to the development of PU.1 knockdown-induced AML by blocking differentiation and increasing self-renewal. Therefore, examination of disturbed gene expression in HSCs can identify genes whose dysregulation is essential for leukemic stem cell function and that are targets for therapeutic interventions.