Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sixteen patients who underwent a second allogeneic hematopoietic stem cell transplantation (HSCT2) for leukemia relapse after the first allogeneic transplantation (HSCT1) were studied. The patients included 7 patients with acute myelogenous leukemia, 8 with acute lymphoblastic leukemia, and 1 with chronic myelogenous leukemia. The median patient age at HSCT2 was 22 years (range, 12 to 44 years). The median interval between HSCT1 and HSCT2 was 19 months (range, 2 to 46 months). At HSCT2, 7 patients were in complete remission (CR), 7 had relapsed, and 2 had bone marrow aplasia. In 14 patients, donors for HSCT2 were the same as those for HSCT1. Two donors were replaced, 1 for another HLA-matched sibling and 1 for an unrelated cord blood donor. Four patients (25%) died within 100 days after HSCT2 from veno-occlusive disease, sepsis, interstitial pneumonitis, or chronic graft-versus-host disease (GVHD), without leukemia relapse. Seven patients (44%) developed leukemia relapse and died between 4 and 20 months after HSCT2. Five patients (31%) survived beyond 4 years. One patient died from chronic GVHD without leukemia relapse 55 months after HSCT2. The 4 other patients were alive between 79 and 134 months after HSCT2 (median follow-up, 106 months). Factors that favorably influenced survival were age younger than 20 years and CR duration after HSCT1 longer than 12 months. HSCT2 is considered to be beneficial for select patients. Preparative regimens, GVHD prophylaxis, and donor choice for HSCT2 need to be studied to obtain a more successful outcome for HSCT2.
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PMID:Second allogeneic hematopoietic stem cell transplantation for leukemia relapse after first allogeneic transplantation: outcome of 16 patients in a single institution. 1199 64

Gemtuzumab ozogamicin (GO; Mylotarg) was developed to treat CD33(+) acute myeloid leukemia (AML). To date, only studies in adults and preliminary data from a phase 1 study in children have been reported. We report data on 15 children with relapsed/refractory CD33(+) AML who were treated with GO monotherapy on compassionate use basis (4-9 mg/m(2) up to 3 courses). Eight children showed a reduction in bone marrow blasts to 5% or less, including 5 in complete remission without full platelet recovery (CRp). Three of the 5 children with CRp received transplants almost directly following the last GO course, without awaiting further platelet regeneration. Hence in these children no clear discrimination between complete remission (CR) and CRp could be made. In 6 of 8 responding patients further treatment was given consisting of stem cell transplantation (SCT). Two patients are still alive, currently 6 and 9 months after SCT. Hematologic toxicity was difficult to assess due to subsequent SCT or leukemia. Side effects, in one patient each included veno-occlusive disease, transient grade 3 hyperbilirubinemia, transient grade 3 transaminase elevation, and grade 3 hypotension during GO administration. No infections or mucositis occurred. This report demonstrates clinical efficacy of GO in a subset of relapsed/refractory pediatric CD33(+) AML patients and suggests that intensive postremission therapy after remission induction by GO may result in durable responses in some patients, although follow-up is still short. Further studies are needed to determine the efficacy and safety of GO in children with AML.
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PMID:Gemtuzumab ozogamicin: first clinical experiences in children with relapsed/refractory acute myeloid leukemia treated on compassionate-use basis. 1254 68

Defibrotide (DF), a polydeoxyribonucleotide with antithrombotic properties, has recently proven effective in patients with severe hepatic veno-occlusive disease (VOD), a life-threatening complication of high-dose chemo/radiotherapy regimens for stem cell transplantation. To understand the mechanism of its beneficial effect, we studied the impact of DF on the expression of tissue factor (TF) and fibrinolytic proteins (PAI-1 and t-PA) on endothelial cells. The in vitro response to DF of two types of human endothelial cells (ECs) of different origins, that is from macrovascular (HUVEC) and microvascular (HMEC-1 cell line) beds, was evaluated in the presence or absence of a proinflammatory stimulus (ie bacterial endotoxin, LPS). The results show that DF was able to significantly reduce the LPS-induced TF expression by HMEC-1, and less prominently by HUVEC. In addition, DF importantly influenced the fibrinolytic properties of both HMEC-1 and HUVEC. Specifically, it dose-dependently counteracted the LPS-induced increase in PAI-1 levels and decrease in t-PA activity expression. It also significantly incremented t-PA antigen in resting EC. Decreasing the procoagulant activity and increasing the fibrinolytic potential of EC favors an anticoagulant phenotype of the endothelium, which may protect from fibrin deposition and vascular occlusion.
Leukemia 2003 Aug
PMID:Defibrotide reduces procoagulant activity and increases fibrinolytic properties of endothelial cells. 1288 53

The case records of 99 consecutive children with acute lymphoblastic leukaemia who received either 6-thioguanine (6-TG) or 6-mercaptopurine (6-MP) as maintenance therapy for at least 1 year were reviewed for hepatic veno-occlusive disease (VOD). Overall, 12% of those on 6-TG developed VOD (all boys). Isolated persistent thrombocytopenia appeared to be the earliest indicator of incipient VOD. Multivariate analysis identified male sex and 6-TG as risk factors. In all cases, VOD was mild and reversible on withdrawing 6-TG or replacing it with 6-MP. The data implicate a sex-linked polymorphic variation in xenobiotic pathways of thiopurine metabolism in the pathogenesis of VOD.
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PMID:Veno-occlusive disease in patients receiving thiopurines during maintenance therapy for childhood acute lymphoblastic leukaemia. 1508 28

Most of the preparative regimens before allogeneic bone marrow transplantation include cyclophosphamide (Cy) with either busulfan (Bu) or total body irradiation (TBI). The Bu-Cy regimen has shown an advantage in chronic myeloid leukemia and TBI-Cy remains the standard conditioning regimen in acute lymphoblastic leukemia, but results are more conflicting in acute myeloid leukemia (AML). We report here the results of the most important studies comparing these two preparative regimens in AML. Survival is superior in all studies for patients treated with TBI and reached statistical significance in one of four trials. Two of three trials show significantly reduced transplant mortality and leukemia relapse. Higher incidences of veno-occlusive disease and hemorrhagic cystitis are reported with Bu. However, our long-term follow-up is limited, and to date no definitive conclusion can be drawn regarding late side effects. New approaches aiming at minimizing the toxicity without impairing the efficacy, such as targeted Bu plasma levels and nonmyeloablative conditioning regimens, seem promising but need to be evaluated further in future prospective studies.
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PMID:Busulfan-cyclophosphamide versus total body irradiation-cyclophosphamide as preparative regimen before allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia: what have we learned? 1466 23

Peliosis is a pathological entity characterized by the gross appearance of multiple cyst-like, blood-filled cavities within parenchymatous organs. Peliosis has been related to several underlying debilitating illnesses such as tuberculosis, hematological malignancies, the acquired immunodeficiency syndrome (AIDS), and post-transplant immunodeficiency, as well as intravenous drug abuse, chronic alcoholism, and in conjunction with the intake of oral contraceptives or steroids. The classical pathoanatomical concept is based upon the opinion that peliosis exclusively develops in organs belonging to the mononuclear phagocytic system (liver, spleen, bone marrow, and lymph nodes). However, a paucity of studies indicates that other organs such as lungs, parathyroid glands, and kidneys may be affected too. Concerning the underlying pathogenetic mechanisms of onset and maintenance of peliosis, the morphological data obtained by different investigators suggest that there is more than one path of formal pathogenesis (e.g., congenital malformation of vessels manifesting under altered local intravascular pressure conditions, acquired vascular disorder triggered by toxic noxae, active proliferation of vessels corresponding to the benign end on the spectrum of neoplastic vascular lesions). In the liver, at gross inspection, the peliotic lesions give the cut sections a "swiss cheese" appearance. Microscopically, two different types of peliosis can be distinguished in the liver: (1) "parenchymal peliosis" consisting of irregular cavities that are neither lined by sinusoidal cells nor by fibrous tissue, and (2) "phlebectatic peliosis" characterized by regular, spherical cavities lined by endothelium and/or fibrosis. One of the differential diagnoses that most closely resembles peliosis hepatis is secondary hepatic congestion due to veno-occlusive disease or the Budd-Chiari syndrome. In the spleen, the peliotic lesions may be arranged sporadically, disseminated, or in clusters in an uneven distribution pattern. Histologically, the cavities show frequently well-demarcated margins that may appear focally lined by sinusoidal endothelium, or totally lack a clear cell lining. Differential diagnoses are hemangiomas and involvement of the spleen in hairy-cell leukaemia. Since the disease may culminate in spontaneous rupture of the affected organ and thus may mimic a violent death at autopsy, peliosis is far more than just another morphological curiosity. Awareness of peliosis at autopsy as well as an appreciation for the histopathological changes in less characteristic or advanced cases may become an important issue for both the forensic and clinical pathologist.
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PMID:Pathology of peliosis. 1573 6

Antibodies capable to recognize antigen expressed on cancer cells represents the ideal approach for targeted anti neoplastic therapies. The CD33 antigen is present on 90% of acute myeloid leukemia blasts and is shared on normal hemopoietic cells only on the non stem dillerentiating fraction. Gemtuzumab Ozogamicin (GO) is an engineered humanized antibody anti-CD33 conjugated with a potent intercalating agent, named calicheamicin, which is release only at intracellular level (lower pH), following a selective binding to CD33-positive cells, thus representing a promising approach for target anti-leukemia therapy. GO was approved conditionally by the Federal Drug Administration in May 2000 as a single therapy for first recurrence of Acute Myeloid Leukemia (AML) in a subset of older patients. Since 2000, treatment trials and pilot studies have revealed potential expanded applications along with potential limitations. Phase II trials have confirmed the activity and the efficacy of GO as single agent in the treatment of relapsed AML. More recently, clinical trials on induction and post-remission treatment of adult AML have shown efficacy of GO in combination chemotherapy. The strong and homogeneous CD33 expression in Acute Promyelocytic Leukemia (APL), have resulted in an effective treatment of this disease with GO used as salvage treatment, as well as innovative approach for molecular relapsed patients. However, the incidence of veno-occlusive disease, better defined as sinusoidal occlusive syndrome (SOS), must be taken into account as potential complication associated with the GO administration, especially in patients treated with ablative regimens. In conclusion, the extension of the approval in Italy to AML CD33+ in relapsed, regardless age limitation, along with the ongoing evaluation by the European EMEA, represent the basis for a large clinical application of GO in myeloid malignancies potentially extended to paediatric patients with AML and to ALL CD33+.
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PMID:[Therapeutic advances in neoplastic hematology: target therapy anti-CD33]. 1634 20

Pivotal phase II studies in acute myeloblastic leukemia (AML) patients in first relapse have used gemtuzumab ozogamicin (GO) (Mylotarg) at a dose of 9 mg/m(2) on days 1 and 14. These studies showed a 26% response rate (13% complete remission (CR) and 13% CRp (complete remission with incomplete platelet recovery)) but with high degree of hematological and liver toxicities. Based on in vitro studies showing a re-expression of CD33 antigenic sites on the cell surface of blasts cells after exposure to GO, we hypothesized that fractionated doses of GO may be efficient and better tolerated. Fifty-seven patients with AML in first relapse received GO at a dose of 3 mg/m(2) on days 1, 4 and 7 for one course. Fifteen patients (26%) achieved CR and four (7%) CRp. Remission rate correlated strongly with P-glycoprotein and MRP1 activities. The median relapse-free survival was 11 months, similar for CR or CRp patients. Median duration of neutropenia < 500/microl and thrombocytopenia < 50,000/microl were, respectively, 23 and 21 days. No grade 3 or 4 liver toxicity was observed. No veno-occlusive disease occurred after GO or after hematopoietic stem cell transplantation given after GO in seven patients. Mylotarg administered in fractionated doses demonstrated an excellent efficacy/safety profile.
Leukemia 2007 Jan
PMID:High efficacy and safety profile of fractionated doses of Mylotarg as induction therapy in patients with relapsed acute myeloblastic leukemia: a prospective study of the alfa group. 1705 Dec 46

N-acetylcysteine (NAC) is a known antioxidant and induces modulation of glutathione cellular content effects. It has been suggested that in the context of stem cell transplantation (SCT), NAC can prevent and treat graft-vs.-host disease, veno-occlusive disease and idiopathic pneumonia syndrome. We investigated the possible effect of NAC on graft-vs.-leukemia effect (GVL) and lymphokine activated cells (LAK) activity in murine models. After 10 days of NAC treatment, the cytotoxic activity of the LAK cells did not significantly differ from LAK activity generated from spleen cells obtained from untreated controls. However, NAC mildly suppressed GVL (appearance of leukemia in 8/36 animals treated with NAC as compared to 0/20 in the SCT control group, p=0.023). In spite of this mild suppression of GVL, no negative effect on achievement of donor chimerism was seen. We conclude that NAC usage in SCT may be relatively safe with regard to the GVL effect, yet further clinical studies are warranted.
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PMID:N-acetylcysteine mildly inhibits the graft-vs.-leukemia effect but not the lymphokine activated cells (LAK) activity. 1733 47

We investigated the hypothesis that gemtuzumab ozogamicin (GO), an anti-CD33 immunotoxin would improve the efficacy of fludarabine/melphalan as a preparative regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in a phase I/II trial. Toxicity was defined as grades III-IV organ damage, engraftment failure or death within 30 days. 'Response' was engraftment and remission (CR) on day +30. We sought to determine the GO dose (2, 4 or 6 mg m(-2)) giving the best trade-off between toxicity and response. All patients were not candidates for myeloablative regimens. Treatment plan: GO (day -12), fludarabine 30 mg m(-2) (days -5 to -2), melphalan 140 mg m(-2) (day -2) and HSCT (day 0). GVHD prophylaxis was tacrolimus and mini-methotrexate. Diagnoses were AML (n=47), MDS (n=4) or CML (n=1). Median age was 53 years (range, 13-72). All but three patients were not in CR. Donors were related (n=33) or unrelated (n=19). Toxicity and response rates at 4 mg m(-2) were 50% (n=4) and 50% (n=4). GO dose was de-escalated to 2 mg m(-2): 18% had toxicity (n=8) and 82% responded (n=36). 100-day TRM was 15%; one patient had reversible hepatic VOD. Median follow-up was 37 months. Median event-free and overall survival was 6 and 11 months. GO 2 mg m(-2) can be safely added to fludarabine/melphalan, and this regimen merits further evaluation.
Leukemia 2008 Feb
PMID:Phase I/II study of gemtuzumab ozogamicin added to fludarabine, melphalan and allogeneic hematopoietic stem cell transplantation for high-risk CD33 positive myeloid leukemias and myelodysplastic syndrome. 1798 20


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