Joseph McGuirk

Adult Human Mesenchymal Stem Cells Added to Corticosteroid Therapy for the Treatment of Acute Graft-versus-Host Disease

The unique immunomodulatory properties of mesenchymal stem cells (MSCs) make them a rationale agent to investigate for graft-versus-host disease (GVHD). Human MSCs were used to treat de novo acute GVHD (aGVHD). Patients with grades II-IV GVHD were randomized to receive 2 treatments of human MSCs (Prochymal(R)) at a dose of either 2 or 8 million MSCs/kg in combination with corticosteroids. Patients received GVHD prophylaxis with tacrolimus, cyclosporine, (CsA) or mycophenolate mofetil (MMF). Study endpoints included safety of Prochymal administration, induction of response to Prochymal, and overall response of aGVHD by day 28, and long-term safety. Thirty-two patients were enrolled, with 31 evaluable: 21 males, 10 females; median age 52 years (range: 34-67). Twenty-one patients had grade II, 8 had grade III, and 3 had grade IV aGVHD. Ninety-four percent of patients had an initial response to Prochymal (77% complete response [CR] and 16% partial response [PR]). No infusional toxicities or ectopic tissue formations were reported. There was no difference with respect to safety or efficacy between the low and high Prochymal dose. In conclusion, Prochymal can be infused safely into patients with aGVHD and induces response in a high proportion of GVHD patients.

AMD3100 plus G-CSF can successfully mobilize CD34 + cells from non-Hodgkin's lymphoma, Hodgkin's disease and multiple myeloma patients previously failing mobilization with chemotherapy and/or cytokine treatment : compassionate use data

AMD3100 given with G-CSF has been shown to mobilize CD34+ cells in non-Hodgkins lymphoma (NHL), multiple myeloma (MM), and Hodgkins disease (HD) patients who could not collect sufficient cells for autologous transplant following other mobilization regimens. These poor mobilizers are usually excluded from company-sponsored trials, but have been included in an AMD3100 Single Patient Use protocol, referred to as a Compassionate Use Protocol (CUP). A cohort of 115 data-audited poor mobilizers in CUP was assessed, with the objective being to collect ⩾2 × 106 CD34+ cells per kg following AMD3100 plus G-CSF mobilization. The rates of successful CD34+ cell collection were similar for patients who previously failed chemotherapy mobilization or cytokine-only mobilization: NHL—60.3%, MM—71.4% and HD—76.5%. Following transplant, median times to neutrophil and PLT engraftment were 11 days and 18 days, respectively. Engraftment was durable. There were no drug-related serious adverse events. Of the adverse events considered related to AMD3100, two (1.6%) were severe (one patient—headache, one patient—nightmares). Other AMD3100-related adverse events were mild (84.8%) or moderate (13.6%). The most common AMD3100-related adverse events were gastrointestinal reactions, injection site reactions and paresthesias. AMD3100 plus G-CSF offers a new treatment to collect CD34+ cells for autologous transplant from poor mobilizers, with a high success rate.

Targeting levels or oligomerization of nucleophosmin 1 induces differentiation and loss of survival of human AML cells with mutant NPM1

Nucleophosmin 1 (NPM1) is an oligomeric, nucleolar phosphoprotein that functions as a molecular chaperone for both proteins and nucleic acids. NPM1 is mutated in approximately one-third of patients with AML. The mutant NPM1c+ contains a 4-base insert that results in extra C-terminal residues encoding a nuclear export signal, which causes NPM1c+ to be localized in the cytoplasm. Here, we determined the effects of targeting NPM1 in cultured and primary AML cells. Treatment with siRNA to NPM1 induced p53 and p21, decreased the percentage of cells in S-phase of the cell cycle, as well as induced differentiation of the AML OCI-AML3 cells that express both NPMc+ and unmutated NPM1. Notably, knockdown of NPM1 by shRNA abolished lethal AML phenotype induced by OCI-AML3 cells in NOD/SCID mice. Knockdown of NPM1 also sensitized OCI-AML3 to all-trans retinoic acid (ATRA) and cytarabine. Inhibition of NPM1 oligomerization by NSC348884 induced apoptosis and sensitized OCI-AML3 and primary AML cells expressing NPM1c+ to ATRA. This effect was significantly less in AML cells coexpressing FLT3-ITD, or in AML or normal CD34+ progenitor cells expressing wild-type NPM1. Thus, attenuating levels or oligomerization of NPM1 selectively induces apoptosis and sensitizes NPM1c+ expressing AML cells to treatment with ATRA and cytarabine.

A risk-based approach to optimize autologous hematopoietic stem cell (HSC) collection with the use of plerixafor

Autologous hematopoietic stem cell (HSC) transplant is an effective treatment for patients with hematological malignancies. Unfortunately, 15–30% of patients fail to mobilize a sufficient number of HSCs for the transplant. Plerixafor is now used as a salvage mobilization regimen, with good success. We describe here a risk-based approach for the use of plerixafor, based on the circulating CD34+ cell count and the CD34+ cell dose collected after 4 days of G-CSF, that identifies potential poor HSC mobilizers upfront. A total of 159 patients underwent HSC collections using this approach. Of these, 55 (35%) were identified as high risk owing to low CD34+ cell number or low yield on day 1 of collection, and received plerixafor on the subsequent days of collection. Of the 159 patients, 151 (95%) were able to provide adequate collections with the first mobilization attempt in a median of 1.7 days using this approach. Of the eight who failed initial mobilization, 5 successfully underwent re-mobilization with plerixafor and G-CSF and 3 (1.9%) were mobilization failures. This approach helped to control the overall cost of HSC collections for our BMT program by decreasing the need for remobilization, reducing the number of collection days and avoiding the use of plerixafor in all patients.

Dual PI3K/AKT/mTOR inhibitor BEZ235 synergistically enhances the activity of JAK2 inhibitor against cultured and primary human myeloproliferative neoplasm cells

Hemopoietic progenitor cells (HPC) from myeloproliferative neoplasms (MPN) such as myelofibrosis commonly express mutant JAK2-V617F or other mutations that are associated with increased activities of JAK-STAT5/3, RAS/RAF/MAPK, and PI3K/AKT/mTOR pathways. This confers proliferative and survival advantage on the MPN HPCs. Treatment with JAK tyrosine kinase inhibitor (TKI), for example, TG101209, TG101348 (SAR302503), or INCB018424 (ruxolitinib), inhibits mutant JAK2-mediated signaling. Although effective in reducing constitutional symptoms and splenomegaly, treatment with JAK-TKI does not ameliorate myelofibrosis or significantly improve survival of patients with advanced myelofibrosis. Here, we show that treatment with the dual phosphoinositide-3-kinase (PI3K)/AKT and mTOR inhibitor BEZ235 attenuated PI3K/AKT and mTOR signaling, as well as induced cell-cycle growth arrest and apoptosis of the cultured human JAK2-V617F-expressing HEL92.1.7 (HEL), UKE1 cells, and primary CD34+ myelofibrosis (MF)-MPN cells. Treatment with BEZ235 also induced significant apoptosis of the JAK2-TKI resistant HEL/TGR cells that were selected for resistance against JAK-TKI. Cotreatment with BEZ235 and JAK2-TKI (TG101209 and SAR302503) synergistically induced lethal activity against the cultured and primary CD34+ MPN cells while relatively sparing the normal CD34+ HPCs. These findings create a compelling rationale to determine the in vivo activity of dual PI3K/mTOR inhibitors in combination with JAK inhibitors against myelofibrosis HPCs. Mol Cancer Ther; 12(5); 577–88. ©2013 AACR.

Heat shock protein 90 inhibitor is synergistic with JAK2 inhibitor and overcomes resistance to JAK2-TKI in human myeloproliferative neoplasm cells

Purpose: We determined the activity of hsp90 inhibitor, and/or Janus-activated kinase 2 (JAK2) tyrosine kinase inhibitor (TKI), against JAK2-V617F–expressing cultured mouse (Ba/F3-JAK2-V617F) and human (HEL92.1.7 and UKE-1) or primary human CD34+ myeloproliferative neoplasm (MPN) cells. Experimental Design: Following exposure to the hsp90 inhibitor AUY922 and/or JAK2-TKI TG101209, the levels of JAK2-V617F, its downstream signaling proteins, as well as apoptosis were determined. Results: Treatment with AUY922 induced proteasomal degradation and depletion of JAK2-V617F as well as attenuated the signaling proteins downstream of JAK2-V617F, that is, phospho (p)-STAT5, p-AKT, and p-ERK1/2. AUY922 treatment also induced apoptosis of HEL92.1.7, UKE-1, and Ba/F3-hJAK2-V617F cells. Combined treatment with AUY922 and TG101209 caused greater depletion of the signaling proteins than either agent alone and synergistically induced apoptosis of HEL92.1.7 and UKE-1 cells. Cotreatment with AUY922 and TG101209 also induced significantly more apoptosis of human CD34+ MPN than normal hematopoietic progenitor cells. As compared with the sensitive controls, JAK2-TKI–resistant HEL/TGR and UKE-1/TGR cells exhibited significantly higher IC50 values for JAK2-TKI (P < 0.001), which was associated with higher expression of p-JAK2, p-STAT5, p-AKT, and Bcl-xL, but reduced levels of BIM. Unlike the sensitive controls, HEL/TGR and UKE/TGR cells were collaterally sensitive to the hsp90 inhibitors AUY922 and 17-AAG, accompanied by marked reduction in p-JAK2, p-STAT5, p-AKT, and Bcl-xL, with concomitant induction of BIM. Conclusions: Findings presented here show that cotreatment with hsp90 inhibitor and JAK2-TKI exerts synergistic activity against cultured and primary MPN cells. In addition, treatment with hsp90 inhibitor may overcome resistance to JAK2-TKI in human MPN cells. Clin Cancer Res; 17(23); 7347–58. ©2011 AACR.

Immature platelet fraction as a predictor of platelet recovery following hematopoietic progenitor cell transplantation.

The immature platelet fraction (IPF) as determined by the Sysmex XE-2100 is a rapid automated measure of the least mature component of the platelet population and is thought to correlate with thrombopoietic activity of the marrow. We investigated the ability of IPF to predict platelet recovery following hematopoietic progenitor cell (HPC) transplantation. IPF was compared to standard parameters of hematopoietic recovery, including the immature reticulocyte fraction (IRF), an early predictor of recovery. Fifty patients undergoing peripheral blood HPC transplantation (38 autologous and 12 allogeneic) were followed daily for 11 to 28 days after transplantation with measurement of IPF, IRF, absolute neutrophil counts (ANC) and platelet counts. Mean days to recovery for IPF was 3.1 days less than for platelet count (P <.0001), 3.8 days less than for ANC (P <.0001), and 0.6 days less than for IRF (P = .0477). IPF recovered at least 1 day prior to platelet count in 79% (38 of 48) of patients, and was followed by platelet count recovery within 1 to 12 days (mean, 4.1 days). When autologous and allogeneic patient groups were analyzed separately, IPF recovered significantly earlier than platelet count and ANC in both groups (P <.0001). Thrombopoietin (TPO) levels in 5 patients receiving transplants correlated with IPF; however, this appeared to be secondary to an inverse correlation of both TPO and IPF with platelet count. IPF is comparable to IRF as one of the earliest predictors of hematopoietic recovery following peripheral blood HPC transplantation. IPF could potentially be useful as a predictor of platelet recovery in other bone marrow failure syndromes.

Preclinical and phase i results of decitabine in combination with midostaurin (PKC412) for newly diagnosed elderly or relapsed/refractory adult patients with acute myeloid leukemia

To determine the preclinical activity, clinical maximum tolerated dose (MTD), and recommended phase II dose of midostaurin (MS) combined either sequentially or concurrently with intravenous decitabine (DAC) in newly diagnosed patients 60 years or older or relapsed/refractory adult patients (18 years or older) with acute myeloid leukemia (AML).

Histiocytic/dendritic cell sarcoma arising from follicular lymphoma involving the bone: a case report and review of literature

Histiocytic/dendritic cell sarcomas arising from follicular lymphoma are very rare and poorly understood lesions. We describe a case, which is unique in that it presented with a hipbone lesion simultaneously with axillary lymphadenopathy. Biopsy of the axillary lymph node showed a low-grade follicular lymphoma. The hipbone lesion was comprised two cell populations, one representing diffuse large B cell lymphoma and the other a histiocytic/dendritic sarcoma. The cells of all three lesions contained an IGH/BCL2 rearrangement, suggesting that both diffuse large B cell lymphoma and histiocytic/dendritic sarcoma differentiation developed from the same low grade precursor (follicular lymphoma). This case illustrates that sarcomatous transdifferentiation of follicular lymphoma can be an unpredictable local phenomenon and that it can occur extra nodally in the bone marrow. It may also occur concurrently with the progression of follicular lymphoma to a diffuse large B cell lymphoma.

Fatal GvHD induced by PD-1 inhibitor pembrolizumab in a patient with Hodgkin's lymphoma.

290. 10 Armand P, Nagler A, Weller EA, Devine SM, Avigan DE, Chen Y-B et al. Disabling immune tolerance by programmed death-1 blockade with pidilizumab after autologous hematopoietic stem-cell transplantation for diffuse large B-cell lymphoma: results of an international Phase ii trial. J Clin Oncol 2013; 31: 4199–4206. 11 Villasboas JC, Ansell SM, Witzig TE. Targeting the PD-1 pathway in patients with relapsed classic Hodgkin lymphoma following allogeneic stem cell transplant is safe and effective. Oncotarget (e-pub ahead of print 3 February 2016; doi:10.18632/oncotarget.7177). 12 Mori S, Ahmed W, Patel RD, Dohrer AL. Steroid refractory acute liver GvHD in a Hodgkins patient after allogeneic stem transplant cell transplantation following treatment with anti PD-1 antibody, nivolumab, for relapsed disease. Biol Blood Marrow Transplant 22: S392–S393. ABVD (6 cycles) ICE x 2 Autologous transplant: BEAM Brentuximab Allogeneic transplant: Flu/TBI Brentuximab Pembrolizumab Death from GVHD Diagnosis 7 Months relapse 10 Months 27 Months progression 31 Months 43 Months relapse 58 Months relapse 60 Months death Figure 1. Clinical course of the patient. Letter to the Editor