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M J Borowitz

Publications and source records attributed to M J Borowitz.

At least 37 records · Page 2Linked to original sources
PubMed2000

Improved detection and characterization of paroxysmal nocturnal hemoglobinuria using fluorescent aerolysin.

Paroxysmal nocturnal hemoglobinuria (PNH) is caused by a somatic mutation in the gene PIGA, which encodes an enzyme essential for the synthesis of glycosylphosphatidylinositol (GPI) anchors. The PIGA mutation results in absence or marked deficiency of more than a dozen proteins on PNH blood cells. Current flow cytometric assays for PNH rely on the use of labeled antibodies to detect deficiencies of specific GPI anchor proteins, such as CD59. However, because no single GPI anchor protein is always expressed in all cell lineages, no one monoclonal antibody can be used with confidence to diagnose PNH. We describe a new diagnostic test for PNH, based on the ability of a fluorescently labeled inactive variant of the protein aerolysin (FLAER) to bind selectively to GPI anchors. We compared GPI anchor protein expression in 8 patients with PNH using FLAER and anti-CD59. In all cases, FLAER detected similar or higher proportions of PNH monocytes and granulocytes compared with anti-CD59. Because of the increased sensitivity of detection, FLAER could detect small abnormal granulocyte populations in patients to a level of about 0.5%; samples from healthy control subjects contained substantially fewer FLAER-negative cells. FLAER gives a more accurate assessment of the GPI anchor deficit in PNH.

Anemia, Aplastic↗
PubMed2000

A new primary effusion lymphoma-derived cell line yields a highly infectious Kaposi's sarcoma herpesvirus-containing supernatant.

A primary effusion lymphoma (PEL) cell line, JSC-1, that yields highly infectious Kaposi's sarcoma herpesvirus (KSHV) supernatants was established from the ascitic fluid of a human immunodeficiency virus-positive patient. Flow cytometry showed strong expression of CD45 and lambda light-chain restriction. Southern blot hybridization showed immunoglobulin heavy-chain gene rearrangements in the tumor and the resultant cell line consistent with B-cell lineage. Expression of viral genes was assessed by reverse transcription-PCR and immunohistochemistry. Only latent Epstein-Barr virus (EBV) gene expression was detected, and this was at a low level. In contrast, lytic and latent KSHV gene expression were detected. Tetradecanoyl phorbol acetate and butyrate upregulated KSHV lytic expression, but not EBV lytic expression. Viral supernatant from JSC-1 was much more efficient at infecting primary human dermal microvascular endothelial cells (DMVECs) with KSHV than supernatants from BC-3 or BCP-1 PEL cell lines. Quantitation of viral yields produced by the PEL lines showed at least 2 orders of magnitude more DNase I-resistant KSHV DNA in the JSC-1 supernatant compared to BC-3 or BCP-1 supernatants. KSHV infection in DMVECs was associated with a change from a cobblestone to a spindle shape, LANA expression, and an increased number of mitoses.

Ascitic Fluid↗
PubMed2000

The accuracy of combined cytopathologic and flow cytometric analysis of fine-needle aspirates of lymph nodes.

We studied flow cytometry in 156 fine-needle aspirations (FNAs) of lymph nodes performed between June 1993 and September 1998. Information from flow cytometry was combined with cytomorphologic evaluation, and the diagnosis determined by using combined modalities was compared with tissue biopsy results or clinical follow-up. In 74 cases, a combined cytopathologic-flow cytometric diagnosis of lymphoma was made; histologic material was available for 52 patients; in no case was a benign process found. The lymphoma grade assigned agreed with histopathologic findings in 45 of 48 cases with a specific cytologic diagnosis. Treatment was initiated on the basis of the FNA alone for 17 of 52 patients with a history of lymphoma and in 22 additional patients with no follow-up biopsy. Among 71 cases in which the diagnosis using both modalities was benign, the only false-negative was 1 case of Hodgkin disease. Of the 156 cases, 11 were considered atypical or suggestive of lymphoma; biopsies from 8 of 10 patients revealed lymphoma. A combination of flow cytometry and cytomorphology of cells obtained by FNA of lymph nodes can distinguish between benign and malignant lymphoid infiltrates and support a diagnosis of lymphoma that permits definitive therapy in most cases.

Biopsy, Needle↗
PubMed1999

Acute lymphoblastic leukemia with the (8;14)(q24;q32) translocation and FAB L3 morphology associated with a B-precursor immunophenotype: the Pediatric Oncology Group experience.

Five pediatric patients are described with acute lymphoblastic leukemia (ALL) who at presentation had clinical findings suggestive of B cell ALL and lymphoblasts with FAB L3 morphology and the characteristic t(8;14)(q24;q32). However, the leukemia cells of all five patients failed to express surface immunoglobulin (sIg) and kappa or lambda light chains. Based on initial immunophenotyping results consistent with B-precursor ALL, four of these cases were initially treated with conventional ALL chemotherapy. These four patients were switched to B cell ALL treatment protocols once cytogenetic results became available revealing the 8;14 translocation. The fifth case was treated with B cell ALL therapy from the outset. Four of the five patients are in complete remission at 64, 36, 29 and 13 months from diagnosis. One patient relapsed and died 6 months after initial presentation. These five unusual cases with clinical B cell ALL, the t(8;14), and FAB L3 morphology, but negative sIg, demonstrate the importance of careful and multidisciplinary evaluation of leukemic cells with morphology, cytochemistry, immunophenotyping and cytogenetic analysis. Future identification of patients with this profile will allow us to expand our knowledge regarding prognostic significance and optimal treatment for this rare subgroup of patients.

Adolescent↗
PubMed1999

A limited antibody panel can distinguish B-precursor acute lymphoblastic leukemia from normal B precursors with four color flow cytometry: implications for residual disease detection.

Multiparameter flow cytometry may be used to detect minimal residual disease in acute leukemia because leukemic cells often display aberrant phenotypes when compared to normal cells. One limitation of this approach in B-precursor ALL is that leukemic phenotypes are often qualitatively similar to normal marrow B progenitors, though it has long been recognized that the latter show a predictable pattern of antigen expression with differentiation. In this study we used four-color flow cytometry to define precisely the patterns of normal antigen expression on a series of normal bone marrows using two different four-color combinations of antibodies: CD19-APC/CD45-perCP/CD20-PE/CD10-FITC; and CD19-APC/CD45-perCP/CD9-PE/CD34-FITC. A series of dual parameter displays were created in which normal B precursors occupied predictable regions. We then tested these antibody combinations on a series of 82 cases of B-precursor ALL and found that in 76/82 cases (93%) the first combination demonstrated an abnormal population on at least one of the dual parameter displays, and that 72/77 cases tested (94%) showed an abnormality with the second combination. When taken together, 81/82 cases (99%) showed an abnormality. When purified blasts were serially diluted into normal marrows we found a sensitivity of detection of 1 cell in 10(4) normal marrow cells provided sufficient CD19+ cells were acquired to visualize the abnormal population as a discrete cluster. Because the pattern of antigen expression in normals is very reproducible, it is possible to create a fixed set of geometrical regions to define the normal; this makes analysis of an unknown sample very straightforward. We conclude that our approach could be employed as a simple method for the detection of minimal residual disease in B-precursor ALL, and unlike many other methods should prove applicable to virtually all cases of this malignancy.

Antibodies, Monoclonal↗
PubMed1999

Childhood acute lymphoblastic leukemia with the MLL-ENL fusion and t(11;19)(q23;p13.3) translocation.

PURPOSE: To determine the molecular characteristics, clinical features, and treatment outcomes of children with acute lymphoblastic leukemia (ALL) and the t(11;19)(q23,p13.3) translocation. PATIENTS AND METHODS: A retrospective analysis of leukemic cell karyotypes obtained from patients with new diagnoses of ALL who were treated at St. Jude Children's Research Hospital or by the Pediatric Oncology Group was performed to identify cases with the t(11;19)(q23;p13.3) translocation. Molecular analyses were performed on these cases to determine the status of the MLL gene and the presence of the MLL-ENL fusion transcript. RESULTS: Among 3,578 patients with ALL and successful cytogenetic analysis, we identified 35 patients with the t(11;19)(q23;p13.3) translocation: 13 infants and 11 older children had B-precursor leukemia, whereas 11 patients had a T-cell phenotype. Although all of the cases examined had MLL rearrangements and MLL-ENL fusion transcripts, outcome varied according to age and immunophenotype. Among B-precursor cases, only two of the 13 infants remain in complete remission, compared with six of the 11 older children. Most strikingly, no relapses have occurred among B-precursor patients 1 to 9 years of age or among T-cell patients. CONCLUSION: Although MLL gene rearrangements are generally associated with a dismal outcome in ALL, two distinct subsets with MLL-ENL fusions have an excellent prognosis. Our results suggest that patients with this genetic abnormality who have T-cell ALL or are 1 to 9 years of age should not be considered candidates for hematopoietic stem-cell transplantation during their first remission.

Adolescent↗
PubMed1998

Frequent detection of tumor cells in hematopoietic grafts in neuroblastoma and Ewing's sarcoma.

Many poor-risk neuroblastomas and tumours of the Ewing's sarcoma family (ET) recur despite autologous transplants. Recurrence may be due to tumor cells contained in the BM harvests or PBSC harvests. The objectives of this prospective study were to: (1) determine the incidence and degree of tumor cell contamination in paired BM and PBSC harvests; and (2) determine the efficacy of tumor cell purging by immunomagnetic CD34+ cell selection. 198 samples from 11 consecutive patients with neuroblastoma or Ewing's sarcoma were analyzed. We assayed tumor contamination by RT-PCR assay for PGP 9.5, plus immunohistochemistry for neuroblastoma-specific antigens (the latter in neuroblastoma only). None of these patients had tumor cells detected in their BM by clinical histology immediately before BM or PBSC harvests. However, 82% of PBSC and 89% of backup BM harvests were contaminated with tumor by RT-PCR and/or immunocytochemistry assays. Unselected PBSC and BM harvests contained similar quantities of tumor cells (median, approximately 200000 cells). Cyclophosphamide plus G-CSF mobilization did not affect the incidence or level of contamination in PBSC harvests, as compared to blood obtained before mobilization. Immunomagnetic CD34+ cell selection depleted tumor cells by a median of 3.0 logs for PBSC, and 2.6 logs for BM harvests.

Adolescent↗
PubMed1998

Surface antigen phenotype can predict TEL-AML1 rearrangement in childhood B-precursor ALL: a Pediatric Oncology Group study.

The t(12;21)(p13;q22) is the most common translocation in childhood B-precursor ALL. It results in a TEL-AML1 rearrangement and is associated with a good prognosis. Because many chromosomal alterations in leukemia are associated with distinct cell surface phenotypes, we investigated whether there was an association seen between surface marker expression and the TEL-AML1 rearrangement. Of 166 unselected cases of B-precursor ALL studied by Southern hybridization, 45 cases (27%) showed TEL rearrangement. Blasts of patients with TEL rearrangement were much more likely to be CD9-negative, CD45-positive, CD13 positive, and CD20 negative, but the predictive value of any of these markers for the rearrangement was very low. However, 93% of patients with the TEL rearrangement had blasts that were either negative or only partly positive for CD9; this phenotype was only seen in 27% of patients without the rearrangement. Only information about CD20 expression added to the predictive value of CD9 alone. The predictive value of the phenotype CD9 (negative or partly positive) and CD20 (negative or partly positive), for the TEL rearrangement was prospectively tested on an additional 223 cases, and found to be 88% sensitive and 71% specific for the rearrangement, with a positive predictive value of 47%. Hyperdiploidy, previously shown to correlate negatively with the rearrangement, was a slightly more sensitive indicator (94%) but had a much lower predictive value (28%). Three of eight cases found to be rearranged by Southern hybridization but lacking the characteristic phenotype failed to show evidence of the TEL-AML1 rearrangement by polymerase chain reaction, suggesting that at least some of the discordant cases may involve partner genes other than AML1 in the TEL rearrangement. We conclude that immunophenotyping is highly predictive of the TEL rearrangement. For every 100 patients with B-precursor ALL, we estimate that prescreening by phenotyping would eliminate the need for molecular testing on 57 patients and only two or three of an expected 24 patients with the TEL rearrangement would not be detected.

Antigens, Surface↗
PubMed1998

Prevalence of myeloperoxidase gene expression in infant acute lymphocytic leukemia.

The enzyme myeloperoxidase (MPO; donor: H2O2 oxidoreductase, EC1.11.1.7) is a well-established marker of myeloid differentiation. Most myeloid leukemias express MPO enzyme activity at the light microscopic level, whereas lymphoid leukemias characteristically lack such expression. However, the diagnostic significance of MPO RNA expression or of immunohistochemically detectable MPO protein expression in leukemic blasts is unclear. We studied the prevalence and diagnostic significance of MPO RNA and protein expression in 57 cases of MPO enzyme-negative infant B-precursor acute lymphocytic leukemia (ALL), since the blast cells in this condition have been reported to show a high incidence of coexpression of myeloid-associated antigens. MPO expression was compared with other clinical and laboratory parameters. Of the cases examined, 56% showed detectable MPO expression at the RNA or protein level or both. Most positive cases showed MPO protein in many leukemic blasts, whereas a few cases showed substantial MPO protein expression in only a few blast cells. MPO expression showed no significant correlation with other markers of myeloid differentiation. Leukemic lymphoblasts in infant ALL frequently express MPO at the RNA or protein level; this expression does not imply an overall myeloid phenotype. The leukemic blasts in infant ALL may derive from an immature hematopoietic precursor cell not fully committed to lymphoid differentiation.

Blotting, Northern↗
PubMed1998

Consolidation therapy with antimetabolite-based therapy in standard-risk acute lymphocytic leukemia of childhood: a Pediatric Oncology Group Study.

PURPOSE: To develop antimetabolite-based consolidation regimens that minimize acute and long-term toxicities and improve the survival rate of children with standard-risk B-lineage acute lymphocytic leukemia (ALL). PATIENTS AND METHODS: Seven hundred twenty-seven eligible patients with standard-risk early pre-B ALL were registered onto the study. Seven hundred sixteen patients attained a complete remission (CR) after induction therapy. Of these, 114 patients were randomized to a different regimen and were the subject of a separate report. Six hundred two patients were randomized to receive one the following regimens: intermediate-dose methotrexate (IDMTX) with leucovorin rescue on weeks 7, 10, 13, 16, 19, and 22 (regimen A); regimen A plus asparaginase (ASP) administered intramuscularly (i.m.) weekly for 24 weeks (regimen B); or regimen A plus a 24-hour infusion of cytarabine (AraC) with each IDMTX (regimen C). After consolidation, patients were placed on maintenance therapy through week 156. Regimens A and C were opened in February 1986, and regimen B in May 1987. Comparisons are based on concurrently randomized patients (May 1987 to January 1991 between regimens A and B, and February 1986 to January 1991 between regimens A and C). RESULTS: The 5-year continuous CR (CCR) rates were not significantly different: A versus B, 78.1% (3.9 +/- SE) versus 83.3% +/- 3.5% and A versus C, 79.4% +/- 3.2% versus 83.5% +/- 2.9%; P by one-sided log-rank tests were .27 and .34, respectively. Significant treatment differences were not found with regard to sex, rate of testicular and CNS relapse, or CNS complications. During consolidation, regimen C had significantly more bacterial infections (P = .0032) and days spent in the hospital (P < .001) compared with regimen A. CONCLUSION: We were unable to show a statistical advantage of adding either ASP or AraC to IDMTX in terms of improvement in event-free survival (EFS).

Antimetabolites, Antineoplastic↗
PubMed1998

Prognostic significance of sex in childhood B-precursor acute lymphoblastic leukemia: a Pediatric Oncology Group Study.

PURPOSE: In childhood B-precursor acute lymphoblastic leukemia (ALL), possible interactions among sex, time, and widely used prognostic factors (age, WBC count, and DNA index) were investigated for the first 5 years after diagnosis. PATIENTS AND METHODS: All eligible patients aged 1 to less than 22 years, registered between February 1986 and September 1994 in two B-precursor ALL studies from the Pediatric Oncology Group (POG), were included in the analysis. Cutpoints for age (3.0, 5.0, and 10.0 years), WBC count (10, 50, and 100 x 10(9)/L), and DNA index (DI; 1.16) were defined. Four time periods after diagnosis (years 1, 2, 3, and 4 and 5 combined) were selected for the study of prognostic significance over time. The cut-off date for analysis was April 1996. RESULTS: A total of 3,717 children (2,010 boys and 1,707 girls) were included in the outcome analysis. No major differences between the sexes were observed in age, duration of symptoms before registration, WBC count, hemoglobin level, platelet count, ploidy, presence of CNS disease at diagnosis, or induction failure rate. Event-free survival (EFS) differences between sexes became significantly different from 2 years following diagnosis. At 5 years, in all subsets analyzed, boys fared worse than girls, although not all differences were statistically significant. Major sex differences in EFS were observed in older children (10 to 22 years), in patients with intermediate WBC counts (10 to 50 x 10(9)/ L), and in children who fit both of these subgroups, in whom the 2-year EFS was almost 20% higher in girls than in boys, reaching a 38% difference at 5 years. CONCLUSION: This study shows an outcome interaction among sex, time, and commonly used prognostic variables. The important sex difference observed at 2 and 5 years suggests that more intensive consolidation and/or maintenance therapy in some boys with B-precursor ALL should be investigated.

Adolescent↗
PubMed1998

Myeloperoxidase gene expression in infant leukemia: a Pediatric Oncology Group Study.

A high incidence of co-expression of myeloid-associated antigens in infant B-precursor Acute Lymphocytic Leukemia (B-ALL) has been reported, but the significance of this finding is uncertain. To further assess myeloid differentiation and its prognostic significance in this disease, we investigated the frequency of myeloperoxidase (MPO) gene expression in the blast cells from 43 infants with B-ALL registered in a Pediatric Oncology Group (POG) Pilot Study for Treatment of Infant ALL, utilizing a molecular probe for detection of MPO messenger RNA (mRNA) by Northern blot hybridization and a monoclonal antibody to detect MPO-protein by immunohistochemical staining. Sufficient RNA for Northern blot was extracted from 32 bone marrow or blood samples. In two cases, MPO mRNA was determined by a reverse transcriptase-polymerase chain reaction assay and was negative in both cases. MPO-specific transcripts (MPO+) were present in 19 of 34 (56%) samples analyzed. Immunoreactive MPO protein was positive in 13 of the 20 (65%) patients studied. No correlation was found between MPO gene expression and clinical or laboratory features, karyotypic patterns or clinical outcome. The high frequency of MPO gene expression demonstrated in this study suggests that leukemogenic events in many cases of infant B-ALL appear to involve a pluripotent stem cell not yet fully committed to lymphoid differentiation.

Antibodies, Monoclonal↗
PubMed1998

Clinical utility of flow cytometry in the chronic lymphoid leukemias.

The chronic lymphoid leukemias comprise a number of biologically distinct neoplasms of mature lymphocytes. The availability of specific therapies for certain of these tumors makes accurate diagnosis imperative. In most cases, detailed immunophenotypic analysis of the chronic lymphoid leukemias permits specific classification and initiation of the most appropriate therapy. For example, the characteristic immunophenotype of B-cell chronic lymphocytic leukemia (CLL): CD5+, CD23+, FMC7-, CD20 dim+, clonal surface immunoglobulin (sIg) dim+, distinguishes it from another CD5+ B-cell lymphoproliferative disorder, mantle cell lymphoma, which typically displays the composite phenotype: CD5+, CD23-, FMC7+, CD20 bright+, clonal sIg bright+. Likewise, hairy cell leukemia has a characteristic immunophenotype: CD5-, CD11c bright+, CD25+, CD103+, which distinguishes it from other CD5- B-cell lymphoproliferative disorders, including the morphologically similar splenic lymphoma with circulating villous lymphocytes. Immunophenotypic analysis by flow cytometry may also identify clinically relevant subsets of patients within a diagnostic category of leukemia. Thus, in patients with CLL, deviation from the typical immunophenotype is associated with trisomy 12 and mixed-cell morphology. In summary, careful immunophenotyping by flow cytometry facilitates accurate diagnosis in the chronic lymphoid leukemias, and in some settings, may also offer additional therapeutically relevant information.

Flow Cytometry↗
PubMed1997

Prognostic significance of fluorescence intensity of surface marker expression in childhood B-precursor acute lymphoblastic leukemia. A Pediatric Oncology Group Study.

This report describes the prognostic significance of the intensity of surface membrane antigen expression in a series of 1,231 children older than 1 year with newly diagnosed B-precursor acute lymphoblastic leukemia (ALL) treated on Pediatric Oncology Group (POG) treatment protocols. All patients had dual-color flow cytometric immunophenotyping performed at a central reference laboratory with a standard panel of monoclonal antibodies. The flow cytometers used in the study were calibrated with a standard fluorescence microparticle that permitted conversion of relative fluorescence channels to standard units of mean equivalents of soluble fluorochrome (MESF). In univariate analysis, fluorescence intensity of CD45 and CD20 was significantly associated with event-free survival (EFS), whereas other markers showed no significant correlation with outcome. Patients whose blasts were greater than the 75th percentile of intensity for CD45 (corresponding to 18,000 MESF units with CD45-FITC, or about 8% of the intensity of normal lymphocytes) fared significantly worse than those with lower-density CD45, and those whose blasts were greater than the 25th percentile of intensity for CD20 (corresponding to 17,900 MESF units with CD20-PE) had a poorer EFS. The intensity of both CD45 and CD20 was independently correlated with outcome. There was no significant correlation between intensity of expression of either antigen and traditional clinical risk factors, ploidy, or t(9;22) or t(1;19). All patients with t(4;11) had CD45 intensity greater than the 75th percentile, but CD45 intensity retained its prognostic significance after adjusting for t(4;11). In multivariate analysis, both CD45 intensity greater than the 75th percentile and CD20 intensity greater than the 25th percentile were significantly correlated with poor outcome independently of previously reported poor prognostic factors including National Cancer Institute (NCI) risk group, ploidy, trisomies of 4 and 10, and adverse translocations including t(1;19), t(9;22), and t(4;11). We conclude that in childhood B-precursor ALL, the intensity of expression of CD20 and CD45 provides prognostic information not available from simple consideration of antigen expression as positive or negative, and adds to that obtained from traditional clinical and biologic risk factors.

Adolescent↗
PubMed1997

Blastic natural killer cell leukemia/lymphoma: a clinicopathologic study.

The classification of natural killer (NK)-cell and NK-like T-cell malignancies has undergone significant evolution in recent years. Although examples of NK-cell tumors resembling acute leukemia have been described anecdotally as blastic, blastoid, or monomorphic NK-cell leukemia/lymphoma (NKL/L), the clinical and pathologic features of these tumors have not been systematically defined. We report four patients with blastic NKL/L and describe the clinical, pathologic, and immunophenotypic findings in these cases. All patients were elderly (58-82 years) and presented with cutaneous plaques. Two patients also had adenopathy, and three patients had marrow involvement at presentation. Biopsy of cutaneous lesions showed atypical superficial and deep dermal lymphoid infiltrates. Involved lymph nodes were architecturally effaced by an interfollicular infiltrate with blastic cytologic features. In Wright-Giemsa-stained blood or marrow smears, tumor cells had finely distributed nuclear chromatin, many with nucleoli, and variable amounts of cytoplasm. In contrast to many NK and NK-like T-cell disorders, azurophilic cytoplasmic granules were absent or inconspicuous. The tumor cells were immunophenotypically distinctive. They expressed intermediate density CD45, as is characteristic of blasts; in addition, the cells were positive for HLA-DR, CD2, CD4, and the NK-associated antigen CD56. Surface CD3, cytoplasmic CD3, and CD5 were negative in all cases tested, whereas CD7 was expressed in two cases. In formalin-fixed tissue, tumor cells marked with antibodies to CD43, but not with other T- or B-lineage-related antibodies. All three cases studied for Epstein-Barr viral RNA by in situ hybridization were negative. Although treatments varied, all three patients with clinical follow-up died within months of the diagnosis. The clinical course in two patients culminated in an overtly leukemic phase. These findings suggest that blastic NKL/L represents a distinct clinicopathologic entity, characterized by cutaneous, nodal, and marrow involvement by blastic cells with immunophenotypic characteristics of true NK cells. The disease afflicts elderly patients, pursues an aggressive course, and may culminate in overt leukemia.

Aged↗