159 research outputs found
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Pre-existing invasive fungal infection is not a contraindication for allogeneic HSCT for patients with hematologic malignancies: a CIBMTR study.
Patients with prior invasive fungal infection (IFI) increasingly proceed to allogeneic hematopoietic cell transplantation (HSCT). However, little is known about the impact of prior IFI on survival. Patients with pre-transplant IFI (cases; n=825) were compared with controls (n=10247). A subset analysis assessed outcomes in leukemia patients pre- and post 2001. Cases were older with lower performance status (KPS), more advanced disease, higher likelihood of AML and having received cord blood, reduced intensity conditioning, mold-active fungal prophylaxis and more recently transplanted. Aspergillus spp. and Candida spp. were the most commonly identified pathogens. 68% of patients had primarily pulmonary involvement. Univariate and multivariable analysis demonstrated inferior PFS and overall survival (OS) for cases. At 2 years, cases had higher mortality and shorter PFS with significant increases in non-relapse mortality (NRM) but no difference in relapse. One year probability of post-HSCT IFI was 24% (cases) and 17% (control, P<0.001). The predominant cause of death was underlying malignancy; infectious death was higher in cases (13% vs 9%). In the subset analysis, patients transplanted before 2001 had increased NRM with inferior OS and PFS compared with later cases. Pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT but significant survivorship was observed. Consequently, pre-transplant IFI should not be a contraindication to allogeneic HSCT in otherwise suitable candidates. Documented pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT. However, mortality post transplant is more influenced by advanced disease status than previous IFI. Pre-transplant IFI does not appear to be a contraindication to allogeneic HSCT
Circulating endocannabinoids during hematopoietic stem cell transplantation: A pilot study
AbstractObjectiveHematopoietic stem cell transplantation (HCT) is a stressful and rigorous medical procedure involving significant emotional and immune challenges. The endocannabinoid (eCB) signaling system is involved in regulation of both the immune system and emotional reactivity, yet little is known about its function during HCT. We investigated the role of the eCB signaling system in a group of HCT recipients.MethodsA total of 19 HCT recipients were enrolled and provided psychosocial data and blood samples at three peri-transplant time points: prior to transplant, hospital discharge, and approximately 100 days post-transplant. Psychosocial factors, inflammatory molecules, and the eCBs were determined and assessed for changes over this period and association with each other.ResultsHCT recipients demonstrated significant changes over the peri-transplant period in inflammatory molecules and psychosocial functioning, but not in circulating concentrations of the eCBs. Associations among these variables were most likely to be present pre-transplant and least likely to be present immediately post-transplant, with depressive symptoms and inflammation most significantly associated. The eCB 2-arachidonoylglycerol (2-AG) was significantly, positively associated with both interleukin (IL)-6 and C-reactive protein (CRP) and negatively associated with depressive symptoms.ConclusionsThe eCB signaling system may have alternative sources and regulatory mechanisms in addition to the immune system. Given the significant associations with inflammatory molecules and depressive symptoms in the peri-transplant period, it is important to better understand this system and its potential implications in the setting of complex and stressful medical procedures such as HCT
BCL-2 Inhibition Targets Oxidative Phosphorylation and Selectively Eradicates Quiescent Human Leukemia Stem Cells
SummaryMost forms of chemotherapy employ mechanisms involving induction of oxidative stress, a strategy that can be effective due to the elevated oxidative state commonly observed in cancer cells. However, recent studies have shown that relative redox levels in primary tumors can be heterogeneous, suggesting that regimens dependent on differential oxidative state may not be uniformly effective. To investigate this issue in hematological malignancies, we evaluated mechanisms controlling oxidative state in primary specimens derived from acute myelogenous leukemia (AML) patients. Our studies demonstrate three striking findings. First, the majority of functionally defined leukemia stem cells (LSCs) are characterized by relatively low levels of reactive oxygen species (termed âROS-lowâ). Second, ROS-low LSCs aberrantly overexpress BCL-2. Third, BCL-2 inhibition reduced oxidative phosphorylation and selectively eradicated quiescent LSCs. Based on these findings, we propose a model wherein the unique physiology of ROS-low LSCs provides an opportunity for selective targeting via disruption of BCL-2-dependent oxidative phosphorylation
Modulation of colony stimulating factor release and apoptosis in human colon cancer cells by anticancer drugs
Modulation of the immune response against tumour cells is emerging as a valuable approach for cancer treatment. Some experimental studies have shown that secretion of colony stimulating factors by cancer cells reduces their tumorigenicity and increases their immunogenicity probably by promoting the cytolitic and antigen presenting activities of leukocytes. We have observed that human colon cancer cells (HT-29) are able to secrete granulocyte-macrophage-colony stimulating factor, granulocyte-colony stimulating factor and macrophage-colony stimulating factor when stimulated with cytokines (IL-1ÎČ and TNF-α). In this study we assessed, for the first time, the effects of several anticancer drugs on colony stimulating factor release or apoptosis in HT-29 cells. Cytokine-induced release of granulocyte-macrophage-colony stimulating factor, granulocyte-colony stimulating factor and macrophage-colony stimulating factor was significantly increased by cisplatin and 6-mercaptopurine. Taxol only increased macrophage-colony stimulating factor release while reduced that of granulocyte-colony stimulating factor. No changes in colony stimulating factor secretion were observed after treatment with methotrexate. Only cisplatin and taxol induced apoptosis in these cells. Secretion of colony stimulating factors by colon cancer cells may contribute to the immune host response against them. Anticancer drugs such as cisplatin and 6-mercaptopurine increase colony stimulating factor secretion by cytokine stimulated cancer cells probably through mechanisms different to those leading to cell apoptosis, an effect that may contribute to their anti-neoplasic action
HLA-Identical Sibling Allogeneic Transplants versus Chemotherapy in Acute Myelogenous Leukemia with t(8;21) in First Complete Remission: Collaborative Study between the German AML Intergroup and CIBMTR
AbstractWe studied the role of HLA-matched sibling hematopoietic cell transplantation (HCT) in treating t(8;21) acute myelogenous leukemia (AML) in first remission. Outcomes of 118 patients receiving HCT and reported to the Center for International Blood and Marrow Transplant Research were compared with 132 similar patients receiving chemotherapy selected from 8 German AML Intergroup multicenter trials. Characteristics of the cohorts were similar except that chemotherapy recipients were significantly older. To adjust for time to treatment bias, outcomes were compared using left-truncated Cox regression models. Transplants were associated with higher treatment-related mortality (TRM; relative risk [RR] 6.76, 95% confidence interval [CI] 2.95-15.45, P < .001), lower relapse (RR 0.47, 95% CI 0.25-0.85, P = .01), and similar relapse-free survival (P = .2). Loss of sex chromosomes (LOS) in addition to t(8;21) had a negative impact on overall survival (OS) in patients receiving chemotherapy. Patients without LOS experienced shorter survival after HCT comparing to chemotherapy (RR 3.05, P = .02), whereas patients with LOS had similar survival regardless of postremission therapy. In both cohorts, white blood cell count (WBC) at diagnosis >25 à 109/L was associated with a higher relapse risk (RR = 2.09, P = .03), lower relapse-free (RR = 1.9, P = .008), and OS (RR = 1.91, P = .01). In this cohort of patients with t(8;21) AML, HCT did not improve OS, because reduction of relapse was offset by high TRM. In the group without LOS, survival after chemotherapy was far superior to HCT. These results suggest that patients with t(8;21) AML without poor prognostic factors have higher rates of survival after chemotherapy as a post remission therapy compared to HCT
Scoring System Prognostic of Outcome in Patients Undergoing Allogeneic Hematopoietic Cell Transplantation for Myelodysplastic Syndrome
To develop a system prognostic of outcome in those undergoing allogeneic hematopoietic cell transplantation (allo HCT) for myelodysplastic syndrome (MDS)
Hematopoietic Cell Transplantation Outcomes in Monosomal Karyotype Myeloid Malignancies
The presence of monosomal karyotype (MK+) in acute myeloid leukemia (AML) is associated with dismal outcomes. We evaluated the impact of MK+ in AML (MK+AML, N=240) and in myelodysplastic syndrome (MK+MDS, N=221) on hematopoietic cell transplantation (HCT) outcomes compared to other cytogenetically defined groups (AML, N=3,360; MDS, N=1,373) as reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 1998 to 2011. MK+AML was associated with higher disease relapse (hazard ratio [HR] 1.98, p<0.01), similar transplant related mortality (TRM, HR 1.01, p=0.9) and worse survival (HR 1.67, p<0.01) compared to other cytogenetically defined AML. Among patients with MDS, MK+MDS was associated with higher disease relapse (HR 2.39, p<0.01), higher TRM (HR 1.80, p<0.01) and worse survival (HR 2.02, p<0.01). Subset analyses comparing chromosome 7 abnormalities (del7/7q) with or without MK+ demonstrated higher mortality for MK+ disease in for both AML (HR 1.72, p<0.01) and MDS (HR1.79, p<0.01). The strong negative impact of MK+ in myeloid malignancies was observed in all age groups and using either myeloablative or reduced intensity conditioning regimens. Alternative approaches to mitigate disease relapse in this population are needed
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