Therapy-related myelodysplasia and myeloid leukemia (t-MDS/t-AML) is a distinctive clinical syndrome occurring after exposure to chemotherapy (CT) or radiotherapy (RT).We report findings on 306 consecutive patients referred to our institution with morphologic review and cytogenetic analyses. Since 1972, 141 males and 165 females with a median age of 51 years (range, 3-83 years) at primary diagnosis and 58 years (range, 6-86 years) at secondary diagnosis were analyzed. Patients had been administered various cytotoxic agents, including alkylating agents (240 patients, 78%) and topoisomerase 2 inhibitors (115 patients, 39%).One hundred twenty-one (40%) had undergone CT alone, 43 (14%) had undergone RT alone, and 139 (45%) had undergone both modalities. At diagnosis of t-MDS/t-AML, 282 (92%) had clonal abnormalities involving chromosome 5 (n ؍ 63), chromosome 7 (n ؍ 85), chromosomes 5 and 7 (n ؍ 66), recurring balanced rearrangements (n ؍ 31), other clonal abnormalities (n ؍ 39), or normal karyotype (n ؍ 24). Abnormalities of chromosome 5, 7, or both accounted for 76% of all cases with an abnormal karyotype. Seventeen patients acquired t-MDS/t-AML after autologous stem cell transplantation, but no unique pattern of cytogenetic abnormalities was observed. Shorter latency was observed for patients with balanced rearrangements (median, 28 vs 67 months; P < .0001). Patients with acute leukemia were more likely to have balanced rearrangement than those with myelodysplasia (28% vs 4%; P < .0001). Median survival time after diagnosis of t-MDS/t-AML was 8 months; survival at 5 years was less than 10%. These data confirm and extend previous associations between clinical, morphologic, and cytogenetic findings in t-MDS/t-AML. (Blood. 2003;102:43-52)
Risks of secondary solid cancers among allogeneic hematopoietic cell transplant (HCT) recipients who receive conditioning without total body irradiation are not well known. We evaluated the incidence and risk factors for solid cancers after HCT using high-dose busulfan-cyclophosphamide conditioning in 4318 recipients of first allogeneic HCT for acute myeloid leukemia in first complete remission (N ؍ 1742) and chronic myeloid leukemia in first chronic phase (N ؍ 2576). Our cohort represented 22 041 person-years at risk.Sixty-six solid cancers were reported at a median of 6 years after HCT. The cumulative-incidence of solid cancers at 5 and 10 years after HCT was 0.6% and 1.2% among acute myeloid leukemia and 0.9% and 2.4% among chronic myeloid leukemia patients. In comparison to general population incidence rates, HCT recipients had 1.4؋ higher than expected rate of invasive solid cancers (95% confidence interval, 1.08-1.79, P ؍ .01). Significantly elevated risks were observed for tumors of the oral cavity, esophagus, lung, soft tissue, and brain. Chronic graftversus-host disease was an independent risk factor for all solid cancers, and especially cancers of the oral cavity. Recipients of allogeneic HCT using busulfancyclophosphamide conditioning are at risk for developing solid cancers. Their incidence continues to increase with time, and lifelong cancer surveillance is warranted in this population. (Blood. 2011; 117(1):316-322)
Summary:Cyclosporine (CSP) and short course methotrexate (MTX) have been the gold standard for GVHD prophylaxis for decades. Problems associated with MTX include increased time to hematopoietic engraftment, mucositis, and other organ toxicities. The combination of CSP with mycophenolate mofetil (MMF) has been used successfully for the prevention of graft rejection and GVHD in nonmyeloablative transplantation. We performed a prospective randomized trial comparing CSP and MTX with CSP and MMF in myeloablative (busulfan based) allogeneic 6/6 matched sibling bone marrow transplantation (BMT). The group receiving MMF (n ¼ 21) had significantly less severe mucositis than did the group receiving MTX (n ¼ 19) (21 vs 65%, P ¼ 0.008). Median time to neutrophil engraftment was more rapid in the MMF group (11 vs 18 days, Po0.001). The incidence of acute GVHD, as well as 100 day survival, was similar for both groups. The reduced toxicity of the CSP and MMF arm resulted in premature study closure. We conclude that a GVHD prophylaxis regimen of CSP and MMF after a myeloablative allogeneic preparative regimen is associated with faster hematopoietic engraftment, decreased incidence of mucositis, similar incidence of aGVHD, and comparable survival as compared to CSP and MTX.
Data Sharing Statements: De-identified participant data for BMT CTN 1203 will be deposited in the NHLBI Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC) (https://biolincc.nhlbi.nih.gov/home/); a publicly available database. Study documents including the study protocol, informed consent form, data dictionary, case report forms for data collection are also available via the repository. Data will become accessible 3 years after the end of clinical activity and 2 years after the primary publication, as anticipated in 2020. Instructions on specimen or data requests and contact information for BioLINCC are also available.
Elevated pretransplant ferritin is associated with a lower incidence of chronic graft-versus-host disease and inferior survival after myeloablative allogeneic haematopoietic stem cell transplantation Iron overload is an adverse prognostic factor in patients undergoing allogeneic stem-cell transplantation for thalassaemia (Lucarelli et al, 1993(Lucarelli et al, , 1999. Serum ferritin is a widely utilized indicator for iron stores and elevated levels are associated with worse outcomes following transplantation Pullarkat et al, 2008). Ferritin has been incorporated into prognostic scoring systems for patients undergoing myeloablative allogeneic transplantation for acute leukaemia and myelodysplastic syndrome (Armand et al, 2008).Iron overload is also known to have an immunomodulatory effect (Cunningham-Rundles et al, 2000;Walker & Walker, 2000;Schaible & Kaufmann, 2004). The aim of this study was to assess the influence of pretransplantation ferritin levels on outcomes, including graft-versus-host disease (GVHD), following myeloablative allogeneic stem cell transplantation (HCT). Methods PatientsWe studied 253 consecutive patients who were treated with HCT at the Cleveland Clinic between 20 October 2000 and 4 December 2006. A pretransplantation serum ferritin level (drawn within 100 d preceding transplantation) was available for 222 patients (87AE7%).All patients were treated on clinical trials approved by the Institutional Review Board of the Cleveland Clinic and all patients provided signed informed consent. Preparative regimen and allogeneic stem cell transplantationA busulfan-based preparative regimen was administered to 69% of the patients, 28% received a total body irradiation- SummaryElevated pretransplant serum ferritin levels have been associated with an increased incidence of morbidity and mortality after allogeneic haematopoietic stem cell transplantation (HCT). We studied 222 patients who underwent myeloablative allogeneic HCT in whom pretransplantation serum ferritin levels were available. Pretransplantation ferritin > 1910 lg/l was associated with lower overall survival (P = 0AE003), lower relapse-free survival (P = 0AE003), decreased chronic graft-versus-host disease (GVHD) (P = 0AE019) and increased non-relapse mortality (NRM) (P = 0AE042). Similar results were obtained when pretransplantation ferritin was analysed as a continuous variable and by quartiles. Our results indicate that an elevated pretransplant ferritin level adversely impacts transplantation outcomes. The adverse impact of elevated ferritin on NRM and survival was despite its association with lower incidences of acute and chronic GVHD, which are major causes of NRM. The association of ferritin with iron overload and its influence on HCT outcomes requires further prospective validation.
Suppression of apoptosis by TP53 mutation contributes to resistance of acute myeloid leukemia (AML) to conventional cytotoxic treatment. Using differentiation to induce irreversible cell cycle exit in AML cells could be a p53-independent treatment alternative, however, this possibility requires evaluation. In vitro and in vivo regimens of the deoxycytidine analogue decitabine that deplete the chromatin modifying enzyme DNA methyl-transferase 1 (DNMT1) without phosphorylating p53 or inducing early apoptosis were determined. These decitabine regimens but not equimolar DNA-damaging cytarabine up regulated the key late differentiation factors CEBPε and p27/CDKN1B, induced cellular differentiation, and terminated AML cell-cycle, even in cytarabine-resistant p53- and p16/CDKN2A-null AML cells. Leukemia initiation by xeno-transplanted AML cells was abrogated but normal hematopoietic stem cell (HSC) engraftment was preserved. In vivo, the low toxicity allowed frequent drug administration to increase exposure, an important consideration for S-phase specific decitabine therapy. In xeno-transplant models of p53-null and relapsed/refractory AML, the non-cytotoxic regimen significantly extended survival compared to conventional cytotoxic cytarabine. Modifying in vivo dose and schedule to emphasize this pathway of decitabine action can bypass a mechanism of resistance to standard therapy.
Mechanisms-of-resistance to decitabine and 5-azacytidine, mainstay treatments for myeloid malignancies, require investigation and countermeasures. Both are nucleoside analog pro-drugs processed by pyrimidine metabolism into a deoxynucleotide analog that depletes the key epigenetic regulator DNA methyltranseferase 1 (DNMT1). Here, upon serial analyses of DNMT1 levels in patients' bone marrows on-therapy, we found DNMT1 was not depleted at relapse. Showing why, bone marrows at relapse exhibited shifts in expression of key pyrimidine metabolism enzymes in directions adverse to pro-drug activation. Further investigation revealed the origin of these shifts. Pyrimidine metabolism is a network that senses and regulates deoxynucleotide amounts. Deoxynucleotide amounts were disturbed by single exposures to decitabine or 5azacytidine, via off-target depletion of thymidylate synthase and ribonucleotide reductase respectively. Compensating pyrimidine metabolism shifts peaked 72-96 h later. Continuous pro-drug exposures stabilized these adaptive metabolic responses to thereby prevent DNMT1-depletion and permit exponential leukemia out-growth as soon as day 40. The consistency of the acute metabolic responses enabled exploitation: simple treatment modifications in xenotransplant models of chemorefractory leukemia extended noncytotoxic DNMT1-depletion and leukemia control by several months. In sum, resistance to decitabine and 5-azacytidine originates from adaptive responses of the pyrimidine metabolism network; these responses can be anticipated and thus exploited.
IntroductionAlthough conventional cytotoxic treatments for myeloid cancers can have differing proximal actions, e.g., topoisomerase inhibition (daunorubicin) or termination of DNA chain synthesis (cytarabine), a final common pathway converges onto p53 (TP53), a master regulator of apoptosis (cytotoxicity) (reviewed in ref. 1). As such, TP53 mutation or deletion is associated with resistance to cytotoxic treatments in vitro (2, 3) and in vivo: TP53-mutated acute myeloid leukemia (AML) treated with daunorubicin and/ or cytarabine had a response rate of 33% compared with 81% for TP53 WT AML, while TP53-mutated myelodysplastic syndromes (MDS) had a response rate of 8% versus 60% for MDS with WT TP53 (4). The poorest-risk MDS and AML subtypes, e.g., MDS and AML with complex cytogenetic abnormalities, have the highest rate of TP53 mutations, exceeding 70% in some series (5). Even if TP53 itself is not mutated, alterations in other key p53-system BACKGROUND. Mutational inactivation in cancer of key apoptotic pathway components, such as TP53/p53, undermines cytotoxic therapies that aim to increase apoptosis. Accordingly, TP53 mutations are reproducibly associated with poor treatment outcomes. Moreover, cytotoxic treatments destroy normal stem cells with intact p53 systems, a problem especially for myeloid neoplasms, as these cells reverse the low blood counts that cause morbidity and death. Preclinical studies suggest that noncytotoxic concentrations of the DNA methyltransferase 1 (DNMT1) inhibitor decitabine produce p53-independent cellcycle exits by reversing aberrant epigenetic repression of proliferation-terminating (MYC-antagonizing) differentiation genes in cancer cells. METHODS.In this clinical trial, patients with myelodysplastic syndrome (n = 25) received reduced decitabine dosages (0.1-0.2 mg/kg/day compared with the FDA-approved 20-45 mg/m 2 /day dosage, a 75%-90% reduction) to avoid cytotoxicity. These well-tolerated doses were frequently administered 1-3 days per week, instead of pulse cycled for 3 to 5 days over a 4-to 6-week period, to increase the probability that cancer S-phase entries would coincide with drug exposure, which is required for S-phase-dependent DNMT1 depletion. RESULTS.The median subject age was 73 years (range, 46-85 years), 9 subjects had relapsed disease or were refractory to 5-azacytidine and/or lenalidomide, and 3 had received intensive chemoradiation to treat other cancers. Adverse events were related to neutropenia present at baseline: neutropenic fever (13 of 25 subjects) and septic death (1 of 25 subjects). Blood count improvements meeting the International Working Group criteria for response occurred in 11 of 25 (44%) subjects and were highly durable. Treatment-induced freedom from transfusion lasted a median of 1,025 days (range, 186-1,152 days; 3 ongoing), and 20% of subjects were treated for more than 3 years. Mutations and/or deletions of key apoptosis genes were frequent (present in 55% of responders and in 36% of nonresponders). Noncytotoxic DNMT1 depletion was confirmed b...
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