Cytosine arabinoside with daunorubicin or adriamycin for therapy of acute myelocytic leukemia: a CALGB study

A randomized comparison of the relative efficacy and toxicity of daunorubicin (DNR) at 30 or 45 mg/sq m or adriamycin (ADM) at 30 mg/sq m, given on the first 3 days of a 7-day continuous infusion of cytosine arabinoside (ara-C) at 100 mg/sq m/day, shows the outcome to be dependent on anthracycline, dose, and patient age. DNR 45 is significantly better than DNR 30 or ADM 30 for inducing complete remissions (CR) in patients younger than 60 yr, (72%, 59%, 58% CRs, respectively). DNR 30 is better than DNR 45 or ADM 30 for inducing CR in patients older than 60 yr (47%, 31%, 35%, respectively). There was a corresponding shift in the induction mortality for the age, dose, and anthracycline groups. Adriamycin was significantly more toxic to the gastrointestinal tract than daunorubicin. The duration of complete remission, with cyclic courses of maintenance therapy, was independent of the patient's age, the dose, or choice of anthracycline used in induction, and of whether the maintenance courses were given every 4 wk or every 8 wk.     

Monoclonal CLL B-cells may be induced to grow in an in vitro B-cell colony assay system

A simple reproducible in vitro B-cell colony assay system was used to evaluate B-cell growth in controls and patients with chronic lymphocytic leukemia (CLL). All six CLL patients studied formed B-cell colonies. The number of colonies was significantly less in patients than controls (66 +/- 18 versus 127 +/- 8). CLL colonies were shown to be monoclonal and appeared to reflect the circulating malignant B-cell clone in our patient group, while the six controls studied formed polyclonal B-cell colonies. Wright-Giemsa staining showed typical plasma cells to have developed in the controls but not in the patients. Cells from CLL patients retained a more lymphoid appearance. It is believed that investigations with this B-cell assay will provide the means for further in vitro evaluation of malignant B-cell proliferation in other lymphoproliferative disorders.     

Hydrolysis of benzo[a]pyrene diol epoxide and its covalent binding to DNA proceed through similar rate-determining steps.

The mutagenic and carcinogenic metabolite of benzo[a]pyrene, (7R,8S)-dihydroxy-(9R,10R)-epoxy-7,8, 9,10-tetrahydrobenzo[a]pyrene, undergoes two major reactions in the presence of DNA: (i) hydrolysis and (ii) covalent binding. We report that hydrolysis and covalent binding are specific and general acid-catalyzed reactions with the same or similar rate-determining steps. To account for the similarity of rate-determining steps in covalent binding and hydrolysis we propose and test two models. In each model, the rate-determining step results in formation of a carbonium ion, which serves as a precursor for both tetrol and adduct. In model A the carbonium ion is partitioned between two domains (1 and 2), while in model B there is only one domain. Measurements of pseudo-first-order rate constants, product ratios, and rate ratios support model A, while kinetic results are inconsistent with model B. Domain 1 most likely represents activated benzo[a]pyrenes that are intercalated into DNA, while domain 2 hydrocarbons are physically bound to the outside of the DNA helix.     

Impaired expression of cell surface receptors for B cell growth factor by chronic lymphocytic leukemia B cells

Normal human B cell proliferation is controlled by various immunoregulatory signals including the T cell-derived lymphokine B cell growth factor (BCGF). The role of BCGF in the regulation of malignant B cell proliferation is unclear. Therefore, we studied the proliferative response of purified chronic lymphocytic leukemia (CLL) B cells to BCGF. For all CLL patients studied, CLL B cells showed a decreased proliferative response as compared with control B cells for BCGF- induced B cell proliferation (patient 291 +/- 59 cpm v control 3,942 +/- 622, mean +/- SEM). This impaired proliferative response appeared to be intrinsic to CLL B cells since it was not corrected by incubation with increasing concentrations of BCGF. Attainment of normal B cell responsiveness to BCGF requires the processing of an initial activation signal which results in the expression of cell surface receptors for BCGF. Increasing concentrations of the B cell activation signal (the F(ab')2 fragment of goat anti-human mu chain) did not improve CLL B cell responsiveness to BCGF. Three-day activated CLL B cells compared with activated control B cells demonstrated a marked impairment in their ability to absorb out the BCGF activity present in the BCGF preparation (BCGF activity absorbed out, patient 12.8% v control 53%). Pretreatment of CLL B cells with neuraminidase failed to improve either the proliferative response to BCGF or the expression of cell surface receptors for BCGF by the CLL B cells. This study suggests that the impaired responsiveness to BCGF by CLL B cells is the result of impaired expression of cell surface receptors for BCGF when CLL B cells are exposed to activation signals.     

Impaired responsiveness to B cell growth factor in a patient with common variable hypogammaglobulinemia

Common variable hypogammaglobulinemia (CVH) is a clinical syndrome that includes a diverse group of patients with heterogeneous defects resulting in impaired B cell proliferation and terminal differentiation into mature plasma cells capable of normal immunoglobulin synthesis and secretion. In this study, we report our identification of a previously undescribed intrinsic B cell defect in a patient with CVH. This patient's B cells showed a marked impairment in hemolytic plaque- forming cell (HePFC) formation compared with control B cells (15 v 80 HePFCs per culture, respectively). In addition, this patient's B cells displayed decreased B cell colony formation compared with control B cells (5 +/- 2 v 93 +/- 8, respectively). When examined for their responsiveness to phytohemagglutinin-T cell conditioned media (PHA- TCM), the patient's B cells displayed impaired B cell proliferation compared with control B cells (stimulation index [SI] 1.3 +/- 0.20 v 26 +/- 1.4 with 20% control PHA-TCM [vol/vol]). Impaired proliferation by the patient's B cells persisted with increasing concentrations of B cell growth factor (BCGF). Additionally, PHA-TCM prepared from the patient's T cells when compared with control PHA-TCM consistently showed less support for control B cell proliferation (SI 1.27 +/- 0.21 v 26 +/- 1.4, respectively). In coculture studies of B cell proliferation and immunoglobulin synthesis, patient's T cells showed no evidence of an enhanced suppressive effect or decreased helper effect. This patient's immune defects involve, first, an intrinsic B cell defect characterized by an impaired responsiveness to BCGF's proliferation signal and, second, impaired production of BCGF by the patient's T cells.     

A clinicopathologic correlation of the idiopathic hypereosinophilic syndrome. I. Hematologic manifestations

A retrospective blind study of 32 patients with the hypereosinophilic syndrome was undertaken utilizing a hematologic scoring system that was based on peripheral blood and bone marrow findings, cytogenetics B12 levels, and leukocyte alkaline phosphatase determinations. In addition to the grading system, which allowed formulation of a hematologic score, the date could also be normalized for individuals who did not have all tests performed by use of the hematologic quotient. This study clearly defined two groups of patients within the idiopathic hypereosinophilic syndrome. One group were those individuals with low hematologic scores and quotients who did not require therapy or who responded to prednisone therapy, while the second group of patients required cytotoxic therapy. These patients had significantly higher hematologic scores and quotients and a significant number of abnormalities similar to those seen in myeloproliferative syndromes, such as myelofibrosis and cytogenetic abnormalities. This type of hematologic scoring seems useful in predicting therapy and/or evaluating individuals or groups of patients with the hypereosinophilic syndrome.     

Comparison of first-generation and second-generation blood glucose meters for use in a hospital setting.

This study evaluated and compared a first- and a second-generation blood glucose meter for precision, accuracy, and user preference. Two separate capillary blood glucose fingersticks were performed on 25 outpatients and 60 inpatients with diabetes. Samples were drawn for serum glucose determinations immediately following the capillary fingersticks. Comparison of the Accu-Chek II and Satellite G meters in the outpatient setting gave results similar to the reference laboratory's. When the meters were tested on inpatients, the blood glucose results were significantly higher than those obtained from the hospital laboratory. The Accu-Chek II was more precise than the Satellite G on both normal and high blood glucose samples. Nursing staff indicated preference for the Satellite G because of its quick testing time but not for other preference factors surveyed. Both meters provided more accurate assessments of blood glucose concentration than were obtained from the serum glucose samples routinely processed by our hospital laboratory. Use of a nonfluorinated tube and delayed separation of the sample with resultant glycolysis likely account for this difference.     

Evaluation of carbonic anhydrase IX as a therapeutic target for inhibition of breast cancer invasion and metastasis using a series of in vitro breast cancer models

Triple negative, resistant or metastatic disease are major factors in breast cancer mortality, warranting novel approaches. Carbonic anhydrase IX (CAIX) is implicated in survival, migration and invasion of breast cancer cells and inhibition provides an innovative therapeutic strategy. The efficacy of 5 novel ureido-substituted sulfamate CAIX inhibitors were assessed in increasingly complex breast cancer models, including cell lines in normoxia and hypoxia, 3D spheroids and an ex-vivo explant model utilizing fresh biopsy tissue from different breast cancer subtypes. CAIX expression was evaluated in a tissue microarray (TMA) of 92 paired lymph node and primary breast cancers and 2 inhibitors were appraised in vivo using MDA-MB-231 xenografts. FC11409B, FC9398A, FC9403, FC9396A and S4 decreased cell proliferation and migration and inhibited 3D spheroid invasion. S4, FC9398A and FC9403A inhibited or prevented invasion into collagen. FC9403A significantly reversed established invasion whilst FC9398A and DTP348 reduced xenograft growth. TMA analysis showed increased CAIX expression in triple negative cancers. These data establish CAIX inhibition as a relevant therapeutic goal in breast cancer, targeting the migratory, invasive, and metastatic potential of this disease. The use of biopsy tissue suggests efficacy against breast cancer subtypes, and should provide a useful tool in drug testing against invasive cancers.     

Identification and characterization of a unique subpopulation (CALLA/CD10/negative) of human neutrophils manifesting a heightened chemotactic response to activated complement

We have previously demonstrated that human neutrophils synthesize the common acute lymphoblastic leukemia antigen (CALLA/CD10). To determine whether CALLA/CD10-positive and -negative neutrophils have similar or distinct functional attributes, we sorted normal peripheral blood neutrophils for CALLA/CD10 expression and compared their chemotactic ability. Surprisingly, the low-frequency (approximately 5%), CALLA/CD10- negative neutrophils displayed a dramatically heightened chemotactic response to activated complement (C') that was (a) specific for C', (b) not observed with other minor subpopulations of neutrophils, (c) not due to previous activation in vivo or in vitro, and (d) apparently not due to an increase in C5a receptors. These results underscore the concept of neutrophil heterogeneity and prompt the hypothesis that CALLA/CD10-negative neutrophils may participate in an inflammatory response to trauma involving complement activation.