Hematopoietic insufficiency is the hallmark of acute myeloid leukemia (AML) and predisposes patients to life-threatening complications such as bleeding and infections. Addressing the contribution of ...mesenchymal stromal cells (MSC) to AML-induced hematopoietic failure we show that MSC from AML patients (n=64) exhibit significant growth deficiency and impaired osteogenic differentiation capacity. This was molecularly reflected by a specific methylation signature affecting pathways involved in cell differentiation, proliferation and skeletal development. In addition, we found distinct alterations of hematopoiesis-regulating factors such as Kit-ligand and Jagged1 accompanied by a significantly diminished ability to support CD34+ hematopoietic stem and progenitor cells in long-term culture-initiating cells (LTC-ICs) assays. This deficient osteogenic differentiation and insufficient stromal support was reversible and correlated with disease status as indicated by Osteocalcin serum levels and LTC-IC frequencies returning to normal values at remission. In line with this, cultivation of healthy MSC in conditioned medium from four AML cell lines resulted in decreased proliferation and osteogenic differentiation. Taken together, AML-derived MSC are molecularly and functionally altered and contribute to hematopoietic insufficiency. Inverse correlation with disease status and adoption of an AML-like phenotype after exposure to leukemic conditions suggests an instructive role of leukemic cells on bone marrow microenvironment.
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.
Ineffective hematopoiesis is a major characteristic of myelodysplastic syndromes (MDS) causing relevant morbidity and mortality. Mesenchymal stromal cells (MSC) have been shown to physiologically ...support hematopoiesis, but their contribution to the pathogenesis of MDS remains elusive. We show that MSC from patients across all MDS subtypes (n=106) exhibit significantly reduced growth and proliferative capacities accompanied by premature replicative senescence. Osteogenic differentiation was significantly reduced in MDS-derived MSC, indicated by cytochemical stainings and reduced expressions of Osterix and Osteocalcin. This was associated with specific methylation patterns that clearly separated MDS-MSC from healthy controls and showed a strong enrichment for biological processes associated with cellular phenotypes and transcriptional regulation. Furthermore, in MDS-MSC, we detected altered expression of key molecules involved in the interaction with hematopoietic stem and progenitor cells (HSPC), in particular Osteopontin, Jagged1, Kit-ligand and Angiopoietin as well as several chemokines. Functionally, this translated into a significantly diminished ability of MDS-derived MSC to support CD34+ HSPC in long-term culture-initiating cell assays associated with a reduced cell cycle activity. Taken together, our comprehensive analysis shows that MSC from all MDS subtypes are structurally, epigenetically and functionally altered, which leads to impaired stromal support and seems to contribute to deficient hematopoiesis in MDS.
Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) can be late complications following mutagenic treatment. Limited data is available on the outcome of patients developing ...therapy-related MDS and AML after treatment for multiple myeloma (MM). We identified 250 patients with therapy-associated MDS or AML in the Duesseldorf MDS registry. Of those, 50 patients were previously diagnosed with multiple myeloma (mm-MDS/AML). We compared them to patients with de novo MDS (
n
= 4862) and to patients with MDS following other underlying diseases (tMDS) (
n
= 200). mm-MDS patients and tMDS patients showed similar karyotypes and degrees of cytopenia. However, mm-MDS patients had significantly higher blast counts and more often belonged to the high-risk group according to the International Prognostic Scoring System (IPSS) (both
p
< 0.05). Although the rate of progression to AML was similar in mm-MDS and tMDS, both transformed significantly more often than de novo MDS (
p
< 0.05). Median overall survival of patients with mm-MDS (13 months; range: 1–99) and tMDS (13 months; range 0–160) was also similar yet significantly shorter than patients with de novo MDS (32 months; range 0–345 months; p < 0.05). Furthermore, survival of mm-MDS patients was not affected by myeloma activity. Despite significantly more high-risk disease and higher blast cell counts, myeloma-associated MDS-patients show features akin to other tMDS. Survival is similar to other tMDS and irrespective of myeloma remission status or transformation to AML. Thus, patient outcome is not determined by competing clones but rather by MDS governing the stem cell niche.
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.
Abstract 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.
In patients with multiple myeloma, bendamustine monotherapy is effective as 1st and 2nd line therapy. However, data for patients with advanced multiple myeloma is rare.
In this retrospective analysis ...we have identified 39 patients with relapsed or refractory multiple myeloma by means of case research, who have been treated at our institution with bendamustine as salvage therapy. After in median 2 lines of prior therapy (range: 1-5) patients received in median 3 (range: 1-10) cycles of bendamustine. Bendamustine dosage was 80-150 mg on day 1+2 of a monthly cycle. Bendamustine was administered as monotherapy in 39% of patients, whereas 61% received concomitant steroids.
Toxicity was mild to moderate. Response rates were as follows: 3% vgPR, 33% PR, 18% MR, 26% SD and 20% PD. The median event-free and overall survival were 7 and 17 months, respectively.
In conclusion, in patients with advanced multiple myeloma bendamustine is effective and associated with mild toxicity. Therefore, the role of bendamustine in patients with multiple myeloma should be investigated in further clinical trials.
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