Ronald L. Dubowy
State University of New York Upstate Medical University
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Featured researches published by Ronald L. Dubowy.
Pediatric Blood & Cancer | 2008
Jason Fangusaro; Jonathan L. Finlay; Richard Sposto; Lingyun Ji; Monirath Saly; Stergios Zacharoulis; Shahab Asgharzadeh; Minnie Abromowitch; Randal Olshefski; Steven Halpern; Ronald L. Dubowy; Melanie Comito; Blanca Diez; Stewart J. Kellie; Juliette Hukin; Marc K. Rosenblum; Ira J. Dunkel; Douglas C. Miller; Jeffrey C. Allen; Sharon Gardner
Children with newly diagnosed supratentorial primitive neuroectodermal tumors (sPNET) have poor outcomes compared to medulloblastoma patients, despite similar treatments. In an effort to improve overall survival (OS) and event‐free survival (EFS) and to decrease radiation exposure, the Head Start (HS) protocols treated children with newly diagnosed sPNET utilizing intensified induction chemotherapy (ICHT) followed by consolidation with myeloablative chemotherapy and autologous hematopoietic cell rescue (AuHCR).
Journal of Clinical Oncology | 2006
Mark Bernstein; Meenakshi Devidas; Dominique Lafreniere; Abdul-Kader Souid; Paul A. Meyers; Mark C. Gebhardt; Kimo C. Stine; Richard W. Nicholas; Elizabeth J. Perlman; Ronald L. Dubowy; Irving W. Wainer; Paul S. Dickman; Michael P. Link; Allen M. Goorin; Holcombe E. Grier
PURPOSE Prognosis is poor for Ewing sarcoma patients with metastasis at diagnosis. We intensified a five-drug therapy (ifosfamide, etoposide alternated with vincristine, doxorubicin, and cyclophosphamide) using filgrastim but not stem-cell support. We studied topotecan alone and combined with cyclophosphamide in therapeutic windows before the five-drug therapy. A randomly assigned proportion of patients received amifostine as a cytoprotective agent. PATIENTS AND METHODS Eligible patients were < or = 30 years old and had histologically proven Ewing sarcoma or primitive neuroectodermal tumor (PNET) and metastasis at diagnosis. Chemotherapeutic cycles began every 21 days, after recovery from toxicities. RESULTS One hundred ten of the 117 patients enrolled were eligible. Thirty-six patients received initial topotecan. Three had partial responses (PRs), and 17 had progressive disease (PD). Thirty-seven patients were administered topotecan and cyclophosphamide; 21 of these patients achieved PR, and one patient had PD. In a randomly assigned group of 69 patients, amifostine did not provide myeloprotection, which was measured by absolute neutrophil count, platelet count, or cycle intervals. The best responses to the overall therapy included 45 complete responses, 41 PRs, stable disease in 14 patients, and PD in five patients. For all patients, the 2-year event-free survival (EFS) rate was 24% (+/- 4%), and the overall survival rate was 46% (+/- 5%). For the 39 patients with isolated pulmonary metastases, the 2-year EFS rate was 31% (+/- 7%) compared with 20% (+/- 5%) for patients with more widespread disease. CONCLUSION Topotecan had limited activity in patients with Ewing sarcoma or PNET metastatic at diagnosis. The topotecan-cyclophosphamide combination was active. Amifostine was not myeloprotective. Overall results showed no improvement compared with previous studies.
Pediatric Blood & Cancer | 2007
Stergios Zacharoulis; Adam S. Levy; Susan N. Chi; Sharon Gardner; Marc K. Rosenblum; Douglas C. Miller; Ira J. Dunkel; Blanca Diez; Richard Sposto; Lingyun Ji; Shahab Asgharzadeh; Juliette Hukin; Jean B. Belasco; Ronald L. Dubowy; Stewart J. Kellie; Amanda M. Termuhlen; Jonathan L. Finlay
The purpose of this study is to investigate the efficacy of an intensive chemotherapy induction regimen followed by myeloablative chemotherapy and autologous hematopoietic stem cell rescue (AHSCR) in children with newly diagnosed ependymoma.
Cancer | 1987
Leena Weiss; Robert H. Sagerman; Gerald A. King; Chung T. Chung; Ronald L. Dubowy
The records of 16 patients with optic nerve glioma treated between 1961 and 1984 were reviewed. All patients except two had extension of tumor beyond the chiasm to the hypothalamus, adjacent brain and/or along the posterior optic tract. Eleven of 16 cases were biopsy‐proven, two patients had craniotomy and visual inspection but no biopsy was performed, and in two cases the biopsy was not diagnostic.
Journal of Pediatric Hematology Oncology | 1997
L. S. Frankel; J. Ochs; Jonathan J. Shuster; Ronald L. Dubowy; W. P. Bowman; M. Hockenberry-Eaton; Michael J. Borowitz; Andrew J. Carroll; Charles P. Steuber; D. J. Pullen
PURPOSE Despite improved event-free survival of older children with acute lymphocytic leukemia (ALL), infants <1 year of age continue to have a very poor prognosis. A new therapy designed specifically for infants with ALL was initiated. PATIENTS AND METHODS From 1984 until 1990, 82 eligible infants <1 year of age were entered on a Pediatric Oncology Group (POG) protocol 8493 for infant ALL. Compared to older patients, infants at diagnosis had more overt CNS leukemia (26%), higher initial WBC count (56% >50,000/microl), and a higher likelihood of CD-10 (CALLA) negative lymphoblasts (55%). A translocation involving chromosome 11 at band q23 was detected in 27 of 64 cytogenetically informative cases. Treatment was based upon two institutional pilot studies utilizing chemotherapy doses based upon body weight. Important components included remission induction with cyclophosphamide (Ctx), vincristine (Vcr), cytosine arabinoside (Ara-C), and prednisone (Pred) (COAP); consolidation therapy with teniposide (VM-26) and Ara-C; and continuation therapy with alternating pulses of COAP with VM-26/Ara-C separated by a methotrexate (Mtx) and 6-mercaptopurine (6-MP) backbone plus CNS therapy consisting of standard triple intrathecal therapy (TIT) (Mtx/hydrocortisone/Ara-C), which avoided the use of radiotherapy in this population. RESULTS Seventy-six infants achieved a complete remission (93%). Fifty patients have relapsed: 35 isolated marrow relapses, five isolated CNS relapses, eight combined marrow and CNS relapses, and two other relapses. Actuarial event-free survival was 28% (SE = 5%) at 4 years. Infants >274 days (9 months) at diagnosis had a better outcome than those <274 days. CONCLUSIONS This study represents a modest outcome improvement in comparison to previous experience with ALL for infants treated on POG trials. More effective therapy is still needed for infants with ALL.
Cancer | 1991
Anthony S. Kurec; Patricia Belair; Donna M. Barrett; Frederick R. Davey; Constantino Stefanu; Ronald L. Dubowy
Leukemic cells from 51 pediatric patients (younger than 18 years) diagnosed with acute lymphoid leukemia by standard morphologic and cytochemical methods were subjected to flow cytometric studies using a panel of monoclonal antibodies against T‐cell (CD1, 2, 3, 4, 5, 7, 8), B‐cell (CD10, 19, 20, 21), myeloid (CD13, 14, 15, 33), and HLA‐DR antigens. Cases of “conventional” acute lymphoid leukemia (leukemic cells with a normal configuration of B‐cell or T‐cell differentiation antigens) were observed in 26 of 51 (51%) cases, whereas cases of “aberrant” acute lymphoid leukemia (cells with abnormal patterns of B‐cell or T‐cell antigens or with concomitant myeloid antigens) were noticed in 25 (49%) cases. Myeloid antigen‐positive acute lymphoid leukemia was observed in the leukemic cells of eight (16%) individuals. No significant differences were observed between conventional and aberrant ALL in the distribution of sex, age, leukocyte count, hemoglobin concentration, platelet count, blast count, French‐American‐British (FAB) type, lymphadenopathy, organomegaly, rate or duration of remission, or survival. When only myeloid antigen‐positive cases were compared with myeloid antigen negative‐cases, no significant correlations were observed except for duration of first remission (myeloid antigen positive, 26+ ± 22 months; myeloid antigen negative, 40+ ± 18 months; P < 0.001), and duration of survival (myeloid antigen positive, 27+ ± 24 months; myeloid antigen negative, 62+ ± 17 months; P = 0.001). These data suggest that pediatric patients with ALL blasts possessing myeloid antigens may represent a high‐risk group for length of remission and survival.
Biochemical and Biophysical Research Communications | 1987
B.N. Yamaja Setty; Ronald L. Dubowy; Marie J. Stuart
Endogenous regulators of endothelial cell proliferation have not been clearly defined. We investigated whether the cyclooxygenase and/or lipoxygenase metabolites are involved in this process, and report that lipoxygenase products can modulate endothelial cell growth. Nordihydroguaiaretic acid--a lipoxygenase inhibitor, inhibited endothelial cell proliferation as well as DNA synthesis. 5,8,11,14-Eicosatetraynoic acid--an inhibitor of both lipoxygenase and cyclooxygenase also inhibited endothelial cell DNA synthesis, while indomethacin--a selective cyclooxygenase inhibitor did not affect cell proliferation or DNA synthesis. While arachidonic acid stimulated DNA synthesis, this effect was completely abolished by nordihydroguaiaretic acid. These results demonstrate that products of the lipoxygenase pathway can affect endothelial cell proliferation.
The Lancet Haematology | 2017
Jeffrey A. Jones; Tadeusz Robak; Jennifer R. Brown; Farrukh T. Awan; Xavier Badoux; Steven Coutre; Javier Loscertales; Kerry Taylor; Elisabeth Vandenberghe; Malgorzata Wach; Nina D. Wagner-Johnston; Loic Ysebaert; Lyndah Dreiling; Ronald L. Dubowy; Guan Xing; Ian W. Flinn; Carolyn Owen
BACKGROUND Idelalisib, a selective inhibitor of PI3Kδ, is approved for the treatment of patients with relapsed chronic lymphocytic leukaemia (CLL) in combination with rituximab. We aimed to assess the efficacy and safety of idelalisib in combination with a second-generation anti-CD20 antibody, ofatumumab, in a similar patient population. METHODS In this global, open-label, randomised, controlled phase 3 trial, we enrolled patients with relapsed CLL progressing less than 24 months from last therapy. Patients refractory to ofatumumab were excluded. Patients were stratified by relapsed versus refractory disease, presence or absence of del(17p) or TP53 mutation, or both, and IGHV mutated versus unmutated. We randomised patients in a 2:1 ratio using a web-based interactive system that generated a unique treatment code, and assigned patients to receive either idelalisib plus ofatumumab (oral idelalisib 150 mg twice daily continuously plus ofatumumab 300 mg intravenously in week 1, then 1000 mg intravenously weekly for 7 weeks, and every 4 weeks for 16 weeks) or ofatumumab alone (ofatumumab dosing as per the combination group, except 2000 mg was substituted for the 1000 mg dose). An independent review committee assessed response, including progressive disease, based on imaging using modified International Workshop on Chronic Lymphocytic Leukaemia 2008 criteria. The primary endpoint was progression-free survival assessed by an independent review committee in the intention-to-treat population. We did a primary analysis (data cutoff Jan 15, 2015) and an updated analysis (data cutoff Sept 1, 2015). This trial is registered with Clinicaltrials.gov, number NCT01659021. FINDINGS Between Dec 17, 2012, and March 31, 2014, we enrolled 261 patients (median age 68 years [IQR 61-74], median previous therapies three [IQR 2-4]). At the primary analysis, median progression-free survival was 16·3 months (95% CI 13·6-17·8) in the idelalisib plus ofatumumab group and 8·0 months (5·7-8·2) in the ofatumumab group (adjusted hazard ratio [HR] 0·27, 95% CI 0·19-0·39, p<0·0001). The most frequent grade 3 or worse adverse events in the idelalisib plus ofatumumab group were neutropenia (59 [34%] patients vs 14 [16%] in the ofatumumab group), diarrhoea (34 [20%] vs one [1%]), and pneumonia (25 [14%] vs seven [8%]). The most frequent grade 3 or worse adverse events in the ofatumumab group were neutropenia (14 [16%]), pneumonia (seven [8%]), and thrombocytopenia (six [7%] vs 19 [11%] in the idelalisib plus ofatumumab group). Serious infections were more common in the idelalisib plus ofatumumab group and included pneumonia (23 [13%] patients in the idelalisib plus ofatumumab group vs nine [10%] in the ofatumumab group), sepsis (11 [6%] vs one [1%]), and Pneumocystis jirovecii pneumonia (eight [5%] vs one [1%]). 22 treatment-related deaths occurred in the idelalisib plus ofatumumab group (the most common being sepsis, septic shock, viral sepsis, and pneumonia). Six treatment-related deaths occurred in the ofatumumab group (the most common being progressive multifocal leukoencephalopathy and pneumonia). INTERPRETATION The idelalisib plus ofatumumab combination resulted in better progression-free survival compared with ofatumumab alone in patients with relapsed CLL, including in those with high-risk disease, and thus might represent a new treatment alternative for this patient population. FUNDING Gilead Sciences, Inc.
Molecular Pharmacology | 2006
Corey R. Centerwall; Kirk A. Tacka; Deborah J. Kerwood; Jerry Goodisman; Bonnie B. Toms; Ronald L. Dubowy; James C. Dabrowiak
The interactions of Jurkat cells with cisplatin, cis-[Pt(15NH3)2Cl2](1), are studied using 1H-15N heteronuclear single quantum coherence (HSQC) NMR and inductively coupled plasma mass spectrometry. We show that Jurkat cells in culture rapidly modify the monocarbonato complex cis-[Pt(15NH3)2(CO3)Cl]- (4), a cisplatin species that forms in culture media and probably also in blood. Analysis of the HSQC NMR peak intensity for 4 in the presence of different numbers of Jurkat cells reveals that each cell is capable of modifying 0.0028 pmol of 4 within ∼0.6 h. The amounts of platinum taken up by the cell, weakly bound to the cell surface, remaining in the culture medium, and bound to genomic DNA were measured as functions of time of exposure to different concentrations of drug. The results show that most of the 4 that has been modified by the cells remains in the culture medium as a substance of molecular mass <3 kDa, which is HSQC NMR silent, and is not taken up by the cell. These results are consistent with a hitherto undocumented extracellular detoxification mechanism in which the cells rapidly modify 4, which is present in the culture medium, so it cannot bind to the cell. Because there is only a slow decrease in the amount of unmodified 4 remaining in the culture medium after 1 h, -1.1 ± 0.4 μM h-1, the cells subsequently lose their ability to modify 4. These observations have important implications for the mechanism of action of cisplatin.
Pediatric Blood & Cancer | 2010
Abdul-Kader Souid; Ronald L. Dubowy; Ashish M. Ingle; Maureen G. Conlan; Junfeng Sun; Susan M. Blaney; Peter C. Adamson
To determine the maximum‐tolerated dose, dose‐limiting toxicities, and pharmacokinetics of the kinesin spindle protein inhibitor ispinesib in pediatric patients with recurrent or refractory solid tumors.