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Killer-cell immunoglobulin-like receptors (KIRs) are a family of glycoproteins expressed primarily on natural killer cells that can regulate their function. Inhibitory KIRs recognize MHC class I molecules (KIR-ligands) as ligands. We have reported associations of KIRs and KIR-ligands for patients in two monoclonal antibody (mAb)-based trials: (1) A Children’s Oncology Group (COG) trial for children with high-risk neuroblastoma randomized to immunotherapy treatment with dinutuximab (anti-GD2 mAb) + GM-CSF + IL-2 + isotretinion or to treatment with isotretinoin alone and (2) An Eastern Cooperative Oncology Group (ECOG) trial for adults with low-tumor burden follicular lymphoma responding to an induction course of rituximab (anti-CD20 mAb) and randomized to treatment with maintenance rituximab or no-maintenance rituximab. In each trial, certain KIR/KIR-ligand genotypes were associated with clinical benefit for patients randomized to immunotherapy treatment (immunotherapy in COG; maintenance rituximab in ECOG) as compared to patients that did not receive the immunotherapy [isotretinoin alone (COG); no-maintenance (ECOG)]. Namely, patients with both KIR3DL1 and its HLA-Bw4 ligand (KIR3DL1+/HLA-Bw4+ genotype) had improved clinical outcomes if randomized to immunotherapy regimens, as compared to patients with the KIR3DL1+/HLA-Bw4+ genotype randomized to the non-immunotherapy regimen. Conversely, patients that did not have the KIR3DL1+/HLA-Bw4+ genotype showed no evidence of a difference in outcome if receiving the immunotherapy vs. no-immunotherapy. For each trial, HLA-Bw4 status was determined by assessing the genotypes of three separate isoforms of HLA-Bw4: (1) HLA-B-Bw4 with threonine at amino acid 80 (B-Bw4-T80); (2) HLA-B-Bw4 with isoleucine at amino acid 80 (HLA-B-Bw4-I80); and (3) HLA-A with a Bw4 epitope (HLA-A-Bw4). Here, we report on associations with clinical outcome for patients with KIR3DL1 and these separate isoforms of HLA-Bw4. Patients randomized to immunotherapy with KIR3DL1+/A-Bw4+ or with KIR3DL1+/B-Bw4-T80+ had better outcome vs. those randomized to no-immunotherapy, whereas for those with KIR3DL1+/B-Bw4-I80+ there was no evidence of a difference based on immunotherapy vs. no-immunotherapy. Additionally, we observed differences within treatment types (either within immunotherapy or no-immunotherapy) that were associated with the genotype status for the different KIR3DL1/HLA-Bw4-isoforms. These studies suggest that specific HLA-Bw4 isoforms may differentially influence response to these mAb-based immunotherapy, further confirming the involvement of KIR-bearing cells in tumor-reactive mAb-based cancer immunotherapy.

Background: Studying workflow is a critical step in designing, implementing and evaluating informatics interventions in complex sociotechnical settings, such as hospital emergency departments (EDs). Known approaches to studying workflow in clinical settings attend to the activities of individual clinicians, thus being inadequate to characterize patient care as a cooperative work. Objectives: The purpose of this paper is twofold. First, we introduce a novel, theorydriven patient-oriented workflow methodology, which better addresses the complex, multiple-provider nature of patient care. Second, we report the development of an observational tool and protocol for use in studies of this type, and the results of an evaluation study. Methods: We created a tablet computer implementation of an instrument to efficiently capture patient-oriented workflow, and evaluated it through a field study in three EDs. We focused on activities occurring over time during a single patient care episode as well as the roles of the ED staff members who conducted the activities. Results: The evidence generated supports the validity, viability, and reliability of the tool. The coverage of the tool in terms of activities and roles was satisfactory. The tool was able to capture the sequence of activityrole pairs for 108 patient care episodes. The inter-rater reliability assessment yielded a high kappa value (0.79). Discussion: The patient-oriented workflow methodology has the potential to facilitate modeling patient care in EDs by characterizing both roles and activities in sequence. The methodology also provides researchers and practitioners a more realistic and comprehensive workflow perspective that can inform the design, implementation and evaluation of health information technology interventions. [ABSTRACT FROM AUTHOR]

This is a pilot study performed to determine the maximum tolerated number of courses of high-dose thiotepa and carboplatin with autologous peripheral blood progenitor cell (PBPC) transplantation in poor-risk pediatric central nervous system (CNS) tumor patients. Twelve patients were enrolled and a total of 24 PBPC transplants were performed. The median age was 7.7 years. All patients had CNS tumors: 4 relapsed CNS PNET, 2 high-risk PNET in first remission, 2 relapsed/progressive brainstem tumor, 2 relapsed/progressive anaplastic astrocytoma, 1 relapsed GBM, and 1 recurrent ependymoma. The regimen consisted of thiotepa 250 mg/m2/day × 3 days and carboplatin 400 mg/m2/day × 3 days. No toxic deaths occurred. All patients were hospitalized for a median duration of 17 days. The median number of CD34 cells infused was 5.4 × 106/kg (2.1–29.7 × 106/kg) per course. Median time to ANC >0.5 × 109/L was 9 days, and platelets >20 × 109/L was 13.5 days. Four patients came off protocol after only one course of PBPC (2 had tumor progression, 2 parental choice); 4 patients underwent two, and 4 patients three courses of PBPC. Major nonhematologic complications were mucositis that necessitated infusion of narcotics (11/24 courses), fever of unknown origin (12/24), documented infection (9/24), and hemorrhagic cystitis (3/24). TPN was administered during 22 of 24 courses with a median duration of 15 days. It is feasible to administer 2–3 courses of tandem high-dose thiotepa and carboplatin with PBPC transplant with prompt engraftment and manageable toxicities in pediatric CNS tumor patients. [ABSTRACT FROM AUTHOR]

Telomerase activity and telomere length in mononuclear cells (MNCs) and granulocytes from peripheral blood (PB) and bone marrow (BM) specimens were studied in pediatric acute leukemia (ALL, n = 15; AML, n = 11) and pediatric solid tumor (ST) patients (n = 9) at diagnosis, during and after chemotherapy. In four ST patients, tumor tissue was also available. For comparative analysis, MNCs from healthy donors (n = 53) were analyzed. Telomerase was evaluated using a modified telomeric repeat amplification protocol (TRAP) assay, and telomere length by terminal restriction fragment (TRF) analysis. At diagnosis, high telomerase activity was detected in MNCs from all leukemia patients, which was similar to the activity from ST biopsy specimens. This exceeded by 10- to 20-fold the activity in PB MNCs from ST patients and healthy donors (P < 0.05). Granulocyte fractions lacked telomerase activity in all groups. BM MNCs in leukemia patients revealed a four-fold higher telomerase activity than PB (P = 0.005). After induction chemotherapy and response to treatment, telomerase activity decreased to borderline or undetectable levels in PB MNCs in leukemia (P < 0.01). Average telomeres in PB MNCs from pediatric patients were significantly longer (n = 25; 10.9 kbp) than telomeres in PB and BM MNCs from adult healthy donors (7.45 kbp) (P < 0.0001). At diagnosis, telomeres were shorter from BM compared to PB specimens in leukemia (P < 0.05), and two peak TRFs were observed corresponding to the malignant and normal cell clones. With the attainment of remission, the lower TRF peak, reflecting the leukemic population, was lost. In leukemia patients, mean TRFs increased on average 2.2 kbp after induction chemotherapy, but decreased thereafter on consolidation and maintenance chemotherapy (1 kbp). This was comparable to an average telomere loss of 1.2 kbp in PB specimens from ST patients after chemotherapy. In all patients, telomere loss in granulocytes as compared to MNCs was more pronounced with 1.8 vs 1 kbp, respectively (P = 0.014). Our results demonstrate that at diagnosis, telomerase was consistently and highly upregulated in BM and PB specimens in leukemia, decreased after induction therapy, and correlated with remission. BM specimens in leukemia had higher telomerase activity, probably due to the greater leukemic burden than in PB. Telomeres were significantly longer in children than in adults, but shortened as a consequence of chemotherapy with repeated cycles of hematopoietic regeneration. In acute leukemia, with the loss of the leukemic burden after induction chemotherapy, longer mean TRFs were found, a reflection of the repopulation with normal cells. Our findings suggest that telomerase activity may be useful in the management of childhood malignancies. The significance of telomere length shortening in pediatric patients undergoing chemotherapy and possible telomere regeneration after myelosuppressive treatment remain to be determined. [ABSTRACT FROM AUTHOR]