Norman J Lacayo

Publications (32) View all

• Article: Prognostic features in acute megakaryoblastic leukemia in children without Down syndrome: a report from the AML02 multicenter trial and the Children's Oncology Group Study POG 9421.

  M M O'Brien, X Cao, S Pounds, G V Dahl, S C Raimondi, N J Lacayo, J Taub, M Chang, H J Weinstein, Y Ravindranath, H Inaba, D Campana, C H Pui, J E Rubnitz
  Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 08/2012; · 8.30 Impact Factor
• Source

  Available from: Norman J Lacayo

  Article: Massive evolution of the immunoglobulin heavy chain locus in children with B precursor acute lymphoblastic leukemia.

  Charles Gawad, Francois Pepin, Victoria Carlton, Mark Klinger, Aaron C Logan, David B Miklos, Malek Faham, Gary Dahl, Norman Lacayo
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  ABSTRACT: The ability to distinguish clonal B-cell populations based on the sequence of their rearranged immunoglobulin heavy chain (IgH) locus is an important tool for diagnosing B-cell neoplasms and monitoring treatment response. Leukemic precursor-B-cells may continue to undergo recombination of the IgH gene after malignant transformation; however, the magnitude of evolution at the IgH locus is currently unknown. We used next-generation sequencing to characterize the repertoire of IgH sequences in diagnostic samples of 51 children with B precursor acute lymphoblastic leukemia (B-ALL). We identified clonal IgH rearrangements in 43 of 51 (84%) cases and found that the number of evolved IgH sequences per patient ranged dramatically from 0 to 4,024. We demonstrate that the evolved IgH sequences are not due to amplification artifacts and are unique to leukemic precursor-B-cells. In addition, the evolution often follows an allelic exclusion pattern, where only one of two rearranged IgH loci exhibit ongoing recombination. Thus, precursor-B-cell leukemias maintain evolution at the IgH locus at levels that were previously under-appreciated. This finding sheds light on the mechanisms associated with leukemic clonal evolution and may fundamentally change approaches for monitoring minimal residual disease burden.
  Blood 08/2012; · 9.90 Impact Factor
• Article: Assessing signaling pathways associated with in vitro resistance to cytotoxic agents in AML.

  David B Rosen, James A Cordeiro, Aileen Cohen, Norman Lacayo, Donna Hogge, Rachael E Hawtin, Alessandra Cesano
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  ABSTRACT: This study uses single cell network profiling (SCNP) to characterize biological pathways associated with in vitro resistance or sensitivity to chemotherapeutics commonly used in acute myeloid leukemia (AML) (i.e. cytarabine/daunorubicin, gemtuzumab ozogamicin (GO), decitabine, azacitidine, clofarabine). Simultaneous measurements at the single cell level of changes in DNA damage, apoptosis and signaling pathway responses in AML blasts incubated in vitro with the above drugs showed distinct profiles for each sample and mechanistically different profiles between distinct classes of agents. Studies are ongoing to assess the clinical predictive value of these findings.
  Leukemia research 04/2012; 36(7):900-4. · 2.36 Impact Factor
• Article: Dorsolateral midbrain MRI abnormalities and ocular motor deficits following cytarabine-based chemotherapy for acute myelogenous leukemia.

  Thuy Doan, Norman Lacayo, Paul G Fisher, Yaping Joyce Liao
  Journal of neuro-ophthalmology: the official journal of the North American Neuro-Ophthalmology Society 09/2010; 31(1):52-3. · 1.09 Impact Factor
• Article: A pilot study of an online cognitive rehabilitation program for executive function skills in children with cancer-related brain injury.

  Shelli R Kesler, Norman J Lacayo, Booil Jo
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  ABSTRACT: Children with a history of cancer are at increased risk for cognitive impairments, particularly in executive and memory domains. Traditional, in-person cognitive rehabilitation strategies may be unavailable and/or impractical for many of these children given difficulties related to resources and health status. The feasibility and efficacy of implementing a computerized, home-based cognitive rehabilitation curriculum designed to improve executive function skills was examined in these children. A one-arm open trial pilot study of an original executive function cognitive rehabilitation curriculum was conducted with 23 paediatric cancer survivors aged 7-19. Compliance with the cognitive rehabilitation program was 83%, similar to that of many traditional programs. Following the cognitive intervention, participants showed significantly increased processing speed, cognitive flexibility, verbal and visual declarative memory scores as well as significantly increased pre-frontal cortex activation compared to baseline. These results suggest that a program of computerized cognitive exercises can be successfully implemented at home in young children with cancer. These exercises may be effective for improving executive and memory skills in this group, with concurrent changes in neurobiologic status.
  Brain Injury 01/2011; 25(1):101-12. · 1.36 Impact Factor