John G. Quigley

Nonmyeloablative Stem Cell Transplantation with Alemtuzumab/Low-Dose Irradiation to Cure and Improve the Quality of Life of Adults with Sickle Cell Disease

Allogeneic hematopoietic stem cell transplantation (HSCT) is rarely performed in adult patients with sickle cell disease (SCD). We utilized the chemotherapy-free, alemtuzumab/total body irradiation 300 cGy regimen with sirolimus as post-transplantation immunosuppression in 13 high-risk SCD adult patients between November 2011 and June 2014. Patients received matched related donor (MRD) granulocyte colony-stimulating factor-mobilized peripheral blood stem cells, including 2 cases that were ABO incompatible. Quality-of-life (QoL) measurements were performed at different time points after HSCT. All 13 patients initially engrafted. A stable mixed donor/recipient chimerism was maintained in 12 patients (92%), whereas 1 patient not compliant with sirolimus experienced secondary graft failure. With a median follow-up of 22 months (range, 12 to 44 months) there was no mortality, no acute or chronic graft-versus-host disease (GVHD), and no grades 3 or 4 extramedullary toxicities. At 1 year after transplantation, patients with stable donor chimerism have normalized hemoglobin concentrations and improved cardiopulmonary and QoL parameters including bodily pain, general health, and vitality. In 4 patients, sirolimus was stopped without rejection or SCD-related complications. These results underscore the successful use of a chemotherapy-free regimen in MRD HSCT for high-risk adult SCD patients and demonstrates a high cure rate, absence of GVHD or mortality, and improvement in QoL including the applicability of this regimen in ABO mismatched cases (NCT number 01499888).

Differential effects of epigenetic modifiers on the expansion and maintenance of human cord blood stem/progenitor cells.

Epigenetic therapies, including DNA methyltransferase and histone deacetylase (HDAC) inhibitors, are increasingly being considered to treat hematological malignancies, but their effects on normal hematopoietic stem cells (HSCs) remain largely unexplored. We compared the effects of several HDAC inhibitors, including valproic acid (VPA) and trichostatin A (TSA), alone or in combination with 5-aza-2-deoxycytidine (5azaD) on the expansion of HSCs. VPA induced the highest expansion of CD34+CD90+ cells and progenitor cells compared with other HDAC inhibitors or the sequential addition of 5azaD/TSA in culture. Xenotransplantation studies demonstrated that VPA prevents HSC loss, whereas 5azaD/TSA treatment leads to a net expansion of HSCs that retain serial transplantation ability. 5azaD/TSA-mediated HSC expansion was associated with increased histone acetylation and transient DNA demethylation, which corresponded with higher gene transcript levels. However, some genes with increased transcript levels lacked changes in methylation. Importantly, a global microarray analysis revealed a set of differentially expressed genes in 5azaD/TSA- and VPA-expanded CD34+ cells that might be involved in the expansion and maintenance of transplantable HSCs, respectively. In summary, our data indicate that treatment of HSCs with different chromatin-modifying agents results in either the expansion or maintenance of HSCs, an observation of potential therapeutic importance.

The transcription factor Foxm1 is essential for the quiescence and maintenance of hematopoietic stem cells

Foxm1 is known as a typical proliferation-associated transcription factor. Here we found that Foxm1 was essential for maintenance of the quiescence and self-renewal capacity of hematopoietic stem cells (HSCs) in vivo in mice. Reducing expression of FOXM1 also decreased the quiescence of human CD34+ HSCs and progenitor cells, and its downregulation was associated with a subset of myelodysplastic syndrome (MDS). Mechanistically, Foxm1 directly bound to the promoter region of the gene encoding the receptor Nurr1 (Nr4a2; called Nurr1 here), inducing transcription, while forced expression of Nurr1 reversed the loss of quiescence observed in Foxm1-deficient cells in vivo. Thus, our studies reveal a previously unrecognized role for Foxm1 as a critical regulator of the quiescence and self-renewal of HSCs mediated at least in part by control of Nurr1 expression.

Combination of Linear Accelerator–Based Intensity-Modulated Total Marrow Irradiation and Myeloablative Fludarabine/Busulfan: A Phase I Study

Here we examined the addition of intensity-modulated total marrow irradiation (TMI) delivered using a linear accelerator to a myeloablative chemotherapy conditioning regimen before allogeneic hematopoietic stem cell transplantation (HSCT). In this phase I study, we enrolled 14 patients with high-risk hematologic malignancies who received escalating doses of TMI at 3xa0Gy (nxa0=xa03), 6xa0Gy (nxa0=xa03), 9xa0Gy (nxa0=xa06), and 12xa0Gy (nxa0=xa02) in combination with intravenous (i.v.) fludarabine 160xa0mg/m(2) and targeted busulfan (area under the curve, 4800xa0μM*minute). Peripheral blood mobilized stem cells were obtained from HLA-matched related (nxa0=xa09) or unrelated (nxa0=xa04) or 1 antigen-mismatched unrelated (nxa0=xa01) donors. All patients rapidly engrafted and recovered their immune cells. Overall, Bearman extrahematologic toxicity were limited to grades 1 or 2, with oral mucositis grade 1 in 64% and grade 2 in 36% of the patients. With a median follow-up of 1126xa0days (range, 362 to 1469) for living patients, the overall survival was 50% and relapse-free survival was 43%. Of 7 deaths, 3 were due to relapse and 4 to transplantation-related complications. We conclude that 9xa0Gy TMI can be combined with myeloablative chemotherapy in the design of new preparative regimens for HSCT. This study was registered at clinicaltrials.gov as NCT00988013.

A treatment algorithm to identify therapeutic approaches for leg ulcers in patients with sickle cell disease.

Sickle cell leg ulcers (SCLUs) are a common complication of sickle cell disease (SCD). Patients who develop ulcers appear to have a more severe haemolysis‐associated vasculopathy than individuals who do not develop them, and manifest other complications such as priapism and pulmonary hypertension. SCLUs are slow to heal and often recur, affecting both the emotional and physical well‐being of patients. Here we summarise what is known about the pathophysiology of SCLUs, describe available treatment options and propose a treatment algorithm.

Outcome Disparities in Caucasian and Non-Caucasian Patients With Myeloproliferative Neoplasms.

BACKGROUNDnThe Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) are characterized by an increased risk of thrombotic and hemorrhagic complications. Large retrospective studies have demonstrated racial disparities in MPN outcomes and attributed this to differences in access to health care. Utilizing a single institution experience, we report outcomes in patients with polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis in relation to ethno-racial background.nnnPATIENTS AND METHODSnA total of 127 Caucasian (56%) and non-Caucasian (44%) adult patients with MPNs consecutively treated at the University of Illinois between 1990 and 2012 were examined in this retrospective study. Relationships between ethno-racial background and vascular complications, and disease transformation were evaluated using multivariate logistic regression models.nnnRESULTSnNon-Caucasian PV patients had an increased risk of vascular complications including cardiovascular thrombosis and hemorrhagic events, while Caucasian patients with PV and ET had a higher risk of progression to myelofibrosis. In a Cox proportional hazard regression analysis, Caucasian race emerged as an independent prognostic factor protective against cardiovascular thrombosis in PV and ET patients (hazard ratio, 0.2; 95% confidence interval, 0.03-0.9; Pxa0= .04) while age > 60 years and prior thrombosis were significant risk factors in univariate analysis. Non-Caucasian race was also a significant risk factor in univariate analysis of hemorrhagic complications of PV and ET, and this was largely driven by African American ethnicity.nnnCONCLUSIONnThis study shows for the first time that race can influence clinical outcomes in myeloproliferative neoplasms. Our findings highlight the need for greater representation of non-Caucasian patients in studies investigating vascular risk factors in MPNs.

miR-9 upregulation leads to inhibition of erythropoiesis by repressing FoxO3

MicroRNAs (miRNAs) are emerging as critical regulators of normal and malignant hematopoiesis. In previous studies of acute myeloid leukemia miR-9 overexpression was commonly observed. Here, we show that ectopic expression of miR-9 in vitro and in vivo significantly blocks differentiation of erythroid progenitor cells with an increase in reactive oxygen species (ROS) production. Consistent with this observation, ROS scavenging enzymes, including superoxide dismutase (Sod2), Catalase (Cat), and glutathine peroxidase (Gpx1), are down-regulated by miR-9. In addition, miR-9 suppresses expression of the erythroid transcriptional regulator FoxO3, and its down-stream targets Btg1 and Cited 2 in erythroid progenitor cells, while expression of a constitutively active form of FoxO3 (FoxO3-3A) reverses miR-9-induced suppression of erythroid differentiation, and inhibits miR-9-induced ROS production. Thus, our findings indicate that aberrant expression of miR-9 blocks erythropoiesis by deregulating FoxO3-mediated pathways, which may contribute to the ineffective erythropoiesis observed in patients with hematological malignancies.

A phase 1 trial of autologous stem cell transplantation conditioned with melphalan 200 mg/m2 and total marrow irradiation (TMI) in patients with relapsed/refractory multiple myeloma

Abstract In this phase 1 study, we tested increasing doses of total marrow irradiation (TMI) in addition to standard intravenous melphalan at 200u2009mg/m2 (Mel200) in the conditioning regimen prior to autologous stem cell transplant (ASCT) for multiple myeloma (NCT02043847). Twelve patients aged 18–75 with relapsed myeloma were enrolled in the study and received Mel200 and TMI 3u2009Gy (nu2009=u20093), 6u2009Gy (nu2009=u20093), or 9u2009Gy (nu2009=u20096) prior to transplant. There were no grade 4 extra-hematologic toxicities and a maximum tolerated dose was not reached. Median time to neutrophil and platelet engraftment was 11 and 13 d, respectively. At day 90, 73% of patients were in CR or VGPR. Median progression free survival (PFS) was 449 d and median overall survival (OS) was 966 d. We conclude that TMI at a dose of 9u2009Gy can be safely combined with Mel200 in therapeutic regimens for autologous transplant. Initial clinical results will prompt a phase 2 study.