Maintenance therapy with decitabine in younger adults with acute myeloid leukemia in first remission: a phase 2 Cancer and Leukemia Group B Study (CALGB 10503).

In this prospective phase 2 clinical trial conducted by Cancer and Leukemia Group B (CALGB, now the Alliance), we studied decitabine as maintenance therapy for younger adults with acute myeloid leukemia (AML) who remained in first complete remission (CR1) following intensive induction and consolidation. Given that decitabine is clinically active in AML and with hypomethylating activity distinct from cytotoxic chemotherapy, we hypothesized that 1 year of maintenance therapy would improve disease-free survival (DFS) for AML patients <60 years, who did not receive allogeneic stem cell transplantation in CR1. After blood count recovery from final consolidation, patients received decitabine at 20 mg/m2 intravenously daily for 4-5 days, every 6 weeks for eight cycles. One hundred and thirty-four patients received decitabine and 85 (63%) had favorable risk AML. The median number of cycles received was 7 (range: 1-8) and the primary reason for discontinuation was relapse. DFS at 1 year and 3 years was 79% and 54%, respectively. These results are similar to the outcomes in the historical control comprising similar patients treated on recent CALGB trials. Thus, maintenance with decitabine provided no benefit overall. Standard use of decitabine maintenance in younger AML patients in CR1 is not warranted. This trial was registered at www.clinicaltrials.gov as NCT00416598.

Non-immunosuppressive FTY720-derivative OSU-2S mediates reactive oxygen species-mediated cytotoxicity in canine B-cell lymphoma.

OSU-2S is a FTY720 (Fingolimod) derivative that lacks immunosuppressive properties but exhibits strong anti-tumour activity in several haematological and solid tumour models. We have recently shown OSU-2S to mediate potent cytotoxicity in human mantle cell lymphoma cell lines and primary cells. We report here the pre-clinical activity of OSU-2S in spontaneous B-cell lymphoma of dogs which shares many characteristics of human lymphoma. OSU-2S mediated apoptosis in canine B-cell lines and primary B-cell lymphoma cells obtained from spontaneous lymphoma bearing dogs. OSU-2S induced reactive oxygen species (ROS) in canine lymphoma cells and inhibition of ROS partially rescued OSU-2S-mediated cell death. These studies provide a rational basis for the use of spontaneous lymphoma in pet dogs as a preclinical large animal model for the development of OSU-2S as small molecule for treating people and dogs with lymphoma.

Endothelial chimerism in chronic sclerotic-type chronic graft-versus-host disease (GVHD) and GVHD-associated angiomatosis.

Graft-versus-host disease-associated angiomatosis (GVHD-AA) is an uncommon manifestation of chronic GVHD consisting of friable vascular proliferations. Using fluorescence in situ hybridization, we demonstrate the presence of donor-derived endothelial cells within areas of GVHD-AA. This is the first documented occurrence of a benign neoplastic growth in relationship to a form of chronic GVHD.

The hematopoietic stem cell transplant comorbidity index can predict for 30-day readmission following autologous stem cell transplant for lymphoma and multiple myeloma.

Patients who undergo autologous stem cell transplant (ASCT) for hematologic malignancies frequently have multiple comorbidities. The hematopoietic cell transplantation comorbidity index (HCT-CI), a transplant-specific modification of the Charlson comorbidity index, can predict risk of readmission following allogeneic stem cell transplant. Its utility in the autologous setting is unknown. We evaluated 620 patients who underwent ASCT at the Ohio State University from 2007 to 2012 for lymphoma or multiple myeloma (MM) to identify factors associated with readmission. Univariable and multivariable logistic regression were used to estimate the odds of readmission within 30 days of discharge following ASCT. A Cox proportional hazards model was used to evaluate OS. Sixty-four patients were readmitted within 30 days; the most common indications were fever and prolonged gastrointestinal toxicity. MM compared with lymphoma (odds ratio (OR) 1.89, 95% confidence interval (95% CI): 1.06-3.38, P=0.03), HCT-CI⩾3 (OR 1.74, 95% CI: 1.03-2.96, P=0.04) and length of hospitalization ⩾28 days (OR 3.14, 95% CI: 1.26-7.83, P=0.01) remained significantly associated with 30-day readmission in a multivariable model. While the model had excellent fit (P>0.75), its ability to predict individual patients who would be readmitted was less than acceptable (receiver-operator curve=0.64, 95% CI: 0.57-0.71). In a multivariable proportional hazards model, 30-day readmission (hazards ratio (HR) 1.81, 95% CI: 1.04-3.18, P=0.04), length of hospitalization ⩾28 days (HR 4.93, 95% CI: 2.65-9.18, P<0.001) and chemorefractory disease (HR 3.08, 95% CI: 1.74-5.43, P<0.001) were independently associated with inferior OS, but HCT-CI was not. Evaluation of other assessment tools may allow better prediction of outcomes following ASCT.

Increased anti-leukemic activity of decitabine via AR-42-induced upregulation of miR-29b: a novel epigenetic-targeting approach in acute myeloid leukemia.

Histone deacetylase (HDAC) inhibitors either alone or in combination with hypomethylating agents have limited clinical effect in acute myeloid leukemia (AML). Previously, we demonstrated that AML patients with higher miR (microRNA)-29b expression had better response to the hypomethylating agent decitabine. Therefore, an increase in miR-29b expression preceding decitabine treatment may provide a therapeutic advantage. We previously showed that miR-29b expression is suppressed by a repressor complex that includes HDACs. Thus, HDAC inhibition may increase miR-29b expression. We hypothesized that priming AML cells with the novel HDAC inhibitor (HDACI) AR-42 would result in increased response to decitabine treatment via upregulation of miR-29b. Here, we show that AR-42 is a potent HDACI in AML, increasing miR-29b levels and leading to downregulation of known miR-29b targets (that is, SP1, DNMT1, DNMT3A and DNMT3B). We then demonstrated that the sequential administration of AR-42 followed by decitabine resulted in a stronger anti-leukemic activity in vitro and in vivo than decitabine followed by AR-42 or either drug alone. These preclinical results with AR-42 priming before decitabine administration represent a promising, novel treatment approach and a paradigm shift with regard to the combination of epigenetic-targeting compounds in AML, where decitabine has been traditionally given before HDACIs.