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Biomedical subjects

O Gentilhomme

Publications and source records attributed to O Gentilhomme.

At least 19 recordsLinked to original sources

Burkitt-like lymphomas in AIDS patients: characterization within a series of 103 human immunodeficiency virus-associated non-Hodgkin's lymphomas. Burkitt's Lymphoma Study Group.

PURPOSE: Burkitt-like lymphoma (BLL) is a tumor with morphologic features intermediate between Burkitt's lymphoma (BL) and large-cell lymphoma, but its relationship with these lymphomas is currently unclear. We have therefore analyzed its characteristics within a large series of human immunodeficiency virus (HIV)-associated lymphomas. MATERIALS AND METHODS: Clinical, histologic, immunophenotypic, and molecular analyses were performed on 103 patients with AIDS lymphomas. RESULTS: Nineteen cases (18.4%) were identified as BLL. They were monoclonal B-cell proliferations, as evaluated by immunoglobulin (Ig) gene rearrangement analyses, and had rearrangement of the c-myc oncogene in 68% of cases but not the bcl-2 gene, in contrast to a previous study on non-HIV-associated BLL. This molecular pattern was therefore identical to that of typical BL, suggesting that they represented tumors of similar origin. However, some features could clearly differentiate BLL from BL and were similar to those seen in the diffuse large-cell immunoblastic lymphomas (DLC-IBL) group. These included a greater frequency of Epstein-Barr Virus (EBV) infection (79% v 48%, P = .04), an upregulation of CD39 (50% v 0%, P = .0007) and CD70 (75% v 15%, P = .003) activation antigens and of the CD11a/LFA-1 adhesion molecule (83% v30%, P = .05), and, finally, a lower CD4 count (mean, 119/microL v 270/microL, P = .04). CONCLUSION: BLL is a frequent entity among AIDS lymphomas and should be considered as a morphologic variant of BL in the context of severe immunodepression that occurs in HIV-infected patients.

Adult↗

Phase I study of interleukin-6 in children with solid tumours in relapse.

The aim of this study was to evaluate the feasibility, toxicity and efficacy of escalating doses of subcutaneous recombinant interleukin-6 (IL-6) in children with solid tumours in relapse. Recombinant IL-6 was administered subcutaneously once daily for 14 consecutive days, with a 14 day follow-up period. The starting dose for IL-6 was 1 microgram/kg/day and was escalated in subsequent patients groups until 10 micrograms/kg. Doses were escalated every 3 patients, provided that grade III or IV organ toxicity did not occur at the preceding dose level. Twelve patients were treated, three at each dose level. No grade 3-4 major organ toxicity was observed. Flu-like symptoms and fatigue were the most common side effects. All these symptoms resolved after the end of IL-6 administration. Significant increases in acute-phase proteins (CRP [C reactive protein], fibrinogen) and ESR (Erthrocyte sedimentation rate) were observed in all patients. Stimulatory effects on thrombocytopoiesis were observed at every dose level, and were maximal at 5 micrograms/kg and 10 microgram/kg. There was no tumour response observed during IL-6 administration. Pharmacokinetic profiles performed in 3 patients are consistent with previous reports in adults. IL-6 is a promising new cytokine for paediatric oncology, in particular to increase thrombocyte counts. We recommend that further studies in children proceed at a dose of 5-10 micrograms/kg/day in a once or, better, twice daily administration.

Acute-Phase Proteins↗

Chronic lymphocytic leukaemia with binucleated lymphocytes.

Chronic lymphocytic leukaemia (CLL) is a monoclonal proliferation usually involving B cells and composed of mature lymphoid cells. Distinct morphologic subtypes have been recognized according to lymphocyte size, nuclear:cytoplastic ratio and nucleolus. However the presence of characteristically binucleated lymphocytes in patients fulfilling criteria for CLL diagnosis has never been described. We here report immunological and cytogenetic studies of four patients with CLL but with binucleated lymphocytes. Moreover, trisomy 12, known to be associated with atypical morphology in CLL, was detected in two of these four patients. We suggest that this be considered as a possible new entity.

Aged↗

A chromosome 12 coding region is juxtaposed to the MYC protooncogene locus in a t(8;12)(q24;q22) translocation in a case of B-cell chronic lymphocytic leukemia.

We performed molecular cloning and sequencing of the breakpoints of a new chromosomal translocation involving the MYC protooncogene locus. This secondary t(8;12)(q24;q22) was associated with a primary t(11;14)(q13;q32) translocation in a case of B-cell chronic lymphocytic leukemia (CLL) in blastic transformation. In this leukemia, Northern blot and nuclease analyses SI showed that MYC was strongly expressed with initiation of the transcription at both the 5' and 3' promoters as observed in Burkitt's lymphomas; no coding change was observed in MYC putative regulatory sequences. The breakpoint on chromosome 8 mapped to the 3' end of the MYC locus, in a region containing a potential Z-DNA tract, and where we identified two DNase 1 hypersensitive sites. A rearranged MYC gene fragment was cloned and shown to contain chromosome 12 information by Southern blot analysis and by in situ hybridization. A genomic probe subcloned from the isolated region of the chromosome 12 recognized a 1.8 kb transcript in virtually all the tissues tested but a preferential expression of this new gene, which we termed BTG1 (for B-cell translocation gene 1) was observed in the CLL cells and in tissues of lymphoid origin. This chromosome 12 coding sequence is conserved in evolution and a transcript of similar size is present in murine tissues.

Animals↗

[Colloid substitutes and hematocrit measurement by micromethods].

A study was carried out to determine whether centrifugation and resistivity were reliable methods for measuring haematocrit of blood diluted with dextran or gelatin. The values obtained with the minicentrifuge Compur M 1100 (Bayer) (group 2) and with the Stat-Crit (Fumouze) (group 3) were compared with those obtained with the reference method (Coulter counter Model S + 2, Coultronics) (group 1). The study included 10 healthy subjects, aged 21 to 43 years. In each, sodium, potassium, chloride and protein concentrations were determined. Two further 10 ml blood samples were taken to be diluted with increasing amounts of either a fluid modified gelatin (Plasmion) or a dextran 40 (Piasmacair). The dilutions carried out were 0, 10, 20, 30, 40 and 50%. For each one, the haematocrit was measured using all three methods. The values obtained with undiluted blood were similar with the three methods. However, when blood was diluted with a dextran, haematocrit values were underestimated, whatever method was used, but by no more than 5% (difference not statistically significant). The result was the same with the centrifugation method for blood diluted with gelatin. On the other hand, values obtained with the resistivity technique for these samples were underestimated up to 15.5% (50% dilution; p less than 0.05). This was due to the negative electric charge of the gelatin, which lowered the haematocrit value in proportion to the concentration of gelatin. Although the technique is easier than centrifugation, measuring haematocrit with a resistivity method should be avoided in patients receiving a fluid modified gelatin.

Blood Chemical Analysis↗

Histopathologic features of high-grade non-Hodgkin's lymphomas in acquired immunodeficiency syndrome. The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors.

High-grade B-cell non-Hodgkin's lymphomas are observed in 5% to 10% of patients with acquired immunodeficiency syndrome. To describe their histologic subtypes, a group of pathologists was formed. One hundred thirteen cases were reviewed and classified according to the Working Formulation, the updated Kiel classification, and a recent description of morphologic variants of high-grade B-cell non-Hodgkin's lymphoma. Three major types of intermediate- or high-grade lymphomas were observed: (1) large-cell or centroblastic mainly polymorphic lymphomas with a component of immunoblasts (35 cases); (2) immunoblastic lymphomas with plasmablastic and plasmacytic features in most cases (33 cases); and (3) small non-cleaved cell Burkitt's or non-Burkitt's lymphoma (41 cases), with 15 cases fitting typical criteria of Burkitt's lymphoma and 26 heterogeneous cases in which the size and shape of the cells and the presence of plasmablastic features varied. The most frequent pathologic sites of involvement at presentation were the lymph nodes, gastrointestinal tract, bone marrow, brain, oral cavity, and muscles. A comparison between the histologic type and the site of involvement showed that most cases involving lymph nodes, bone marrow, or muscles were small noncleaved cell Burkitt's or non-Burkitt's lymphomas, while those that affected the gastrointestinal tract, brain, and oral cavity were centroblastic or immunoblastic lymphomas with consistent plasmacytic differentiation. In 10 cases, previous persistent generalized lymphadenopathy syndrome was present. In 13 cases, the lymphomatous proliferation was associated with follicular or diffuse hyperplasia seen on the same lymph node biopsy specimen or in another lymph node.

Acquired Immunodeficiency Syndrome↗

Myelodysplastic syndromes: a study of surface markers and in vitro growth patterns.

A study of surface markers and in vitro growth in semi-solid and liquid medium was performed in 35 patients with newly diagnosed myelodysplastic syndrome (MDS). Surface markers were studied by CD34, CD13, CD14, CD15, and CD33 monoclonal antibodies. There was no strict correlation with the FAB typing, but CD34 was expressed only in refractory anemia with excess of blasts (RAEB) or RAEB in transformation (RAEB-t). CD14 was markedly positive in the 4 cases of chronic myelomonocytic leukemia. Colony-forming cells were assessed by culture in semi-solid medium in the presence of HTB9 as growth factor. Four growth patterns were identified: a) normal growth (6 cases); b) no growth or low plating efficiency (10 cases); c) low colony and high cluster number (15 cases); and d) normal or high colony number with high number of clusters (4 cases). Expression of CD34 was associated with low colony and high cluster number. Finally we studied the proliferation and differentiation capacities in liquid culture without stimulating factor. Fifteen patients had a spontaneous proliferation. This was not correlated with any surface marker. Differentiation assessed by the loss of CD34 and/or the increase of CD15 by more than 20% at day 7 was observed in 21 cases. None of the surface markers or growth patterns was associated with a specific chromosomal abnormality, except the lack of growth in liquid culture observed in all 5q deletion cases. In univariate analysis, RAEB and RAEB-t FAB subtypes, percentage of blasts higher than 5%, staining by CD33 and CD34, and lack of differentiation in liquid culture were significantly associated with progression to leukemia and shorter survival. In multivariate analysis, only CD34 expression (P = .002) and percentage of blasts (P = .05) remained independent significant variables. CD34 was the only significant variable for prediction of survival (P = .05). It is concluded that surface marker analysis at diagnosis and after liquid culture may be a useful tool for the initial evaluation of MDS.

Antigens, CD↗

Break in the BCL1 locus is closely associated with intermediate lymphocytic lymphoma subtype.

The t(11;14)(q13;q32) is a recurring translocation associated with some chronic B-cell lymphocytic malignancies; the putative protooncogene BCL1, located at the chromosome band 11q13, can be involved during the translocation process. In order to determine if BCL1 rearrangement is associated with a particular subtype of lymphoma, we analysed 131 B-cell non-Hodgkin's lymphoma samples by Southern blot analysis, using a BCL1 probe. The BCL1 locus was rearranged in 9 out of 25 (36%) cases of intermediate lymphocytic cell lymphomas (ILL), in 1 out of 8 cases of diffuse small cleaved cell lymphoma, in 1 out of 12 cases of diffuse mixed cell lymphoma, and in 1 out of 21 cases of diffuse large cell lymphoma. In contrast, BCL1 was never found rearranged in any of the 46 follicular lymphomas analysed. The BCL2 gene was in germ-line configuration in all ILL. Sequential hybridization of Southern blots with JH, C mu, and BCLI probes identified comigrating fragments in only one case of ILL, which suggests that, in all the other cases, either the rearrangement of BCL1 did not result from a t(11;14) translocation or the break on chromosome 14 occurred outside the JH or C mu regions. These results indicate that rearrangement of the BCL1 locus may be closely associated with ILL and could be considered as a genotypic marker of this lymphoma subtype.

Blotting, Southern↗

Comparison between image and flow DNA cytometry in non-Hodgkin's lymphomas.

To assess the reliability of DNA estimation in cytological material, Feulgen lymph node imprints from 22 cases of malignant non-Hodgkin's lymphomas were examined by image cytometry (ICM) for both ploidy and cell kinetics, and the results obtained were compared with flow cytometry (FCM). The DNA distribution pattern was less accurate with ICM than with FCM; however, a high correlation was found between proliferative indices (r = 0.91) and between aneuploidy rates (agreement in about 86% of the cases) determined by FCM and ICM. Moreover, DNA tetraploid (or near-tetraploid) stem lines were more easily detected by ICM, due to the morphological selection of lymphomatous cells. The proliferation rate and the aneuploidy frequency according to morphological classification were in agreement with larger, previously reported studies with FCM. Therefore, ICM appears to supply additional complementary information to that obtained with FCM, particularly for the study of heterogeneous cell populations, which may be usefully applied to refine the large cell lymphoma subclassification.

DNA, Neoplasm↗

Immunological detection of neuroblastoma cells in bone marrow harvested for autologous transplantation.

In about 50% of patients with stage IV neuroblastoma, micrometastases are present in the bone marrow when it is harvested for an autograft to follow induction therapy, and the risk of graft contamination by neuroblastoma cells has been the rationale for the use of a purging procedure. However, bone marrow metastases are detected with trephine biopsies which only explore the sites biopsied and do not reflect potential contamination of the pooled marrow harvested for autograft. A two-colour fluorochrome labelling method is described which permits as few as 1 neuroblastoma cell in 100,000 normal bone marrow cells from the autograft to be detected. Three monoclonal antibodies (UJ13A, H11 and 11.14) which react with neuroblastoma cells are used as single reagent in combination with a fourth anti-panleucocyte antibody. This method requires only 2 h for the analysis of three million marrow cells from the autograft, and is more effective than alkaline phosphatase staining with the same monoclonal antibodies. Results were compared with conventional techniques (four biopsies and four aspirates) carried out at the same time in 34 consecutive patients. Of 18 cases with negative aspirates and biopsies, neuroblastoma cells were detected in two autografts by the immunological method. Of 16 cases with positive aspirates and/or biopsies, 10 autografts were positive by the immunological method and six were negative. Thus, marrow micrometastases were detected in 16 of the 34 patients, but the autograft contained malignant cells in only 12 of these patients and the immunological analysis demonstrated that the use of a purging procedure allowed the elimination of neuroblastoma cells from the autograft before its reinjection to the patients.

Antibodies, Monoclonal↗

Surface marker expression in adult acute myeloid leukaemia: correlations with initial characteristics, morphology and response to therapy.

The clinical significance of surface markers was investigated in 145 cases of acute myeloid (AML) or undifferentiated leukaemia (AUL), using a panel of six monoclonal antibodies directed to NHL-30.5 antigen (expressed on poorly differentiated myeloid cells), CD13, CD14, CD15, CD33 and CD34 antigens. Expression of CD14 was correlated with higher leucocyte count, higher serum lactate dehydrogenase level and presentation with extramedullary disease. There was no strict correlation with the French-American-British classification. However, the expression of CD14 was associated with monocytic subtypes. CD15 was mainly expressed in M2 and M3 subtypes, and NHL-30.5 and CD34 antigens in AUL and M1 leukaemias. All patients were treated with the same intensive induction treatment. Staining by three antibodies had a prognostic value. The complete remission (CR) rates were 38% (26/68) in NHL-30.5-positive versus 75% (62/77) in NHL-30.5-negative cases (P less than 10(-5), 50% (37/74) in CD34-positive versus 72% (51/71) in CD34-negative cases (P = 0.007) and 70% (77/110) in CD15-positive versus 31% (11/35) in CD15-negative cases (P less than 10(-4). Expression of NHL-30.5 and CD34 antigen was associated with shorter survival (P less than 10(-3) and P less than 10(-2) respectively), whereas survival was longer in CD15-positive cases (P less than 10(-3). In multivariate analysis, expression of NHL-30.5 antigen, absence of CD15, and high LDH level were associated with poor survival. CR duration was not influenced by any of the factors studied, including antigen expression. These results suggest that leukaemias with less differentiated phenotype have a lower response rate to induction treatment.

Acute Disease↗

Immunocytochemical detection of neuroblastoma cells infiltrating clinical bone marrow samples.

To evaluate the feasibility and clinical usefulness of immunocytochemical detection of bone marrow metastases in neuroblastoma, we studied bone marrow samples from patients undergoing intensive therapy, followed in the majority of cases by autologous bone marrow rescue. Two monoclonal antibodies were used in an indirect immunoenzymatic assay to test 384 samples collected from multiple bone marrow sites during 79 staging procedures in 48 patients. Of 578 immunocytochemical tests, 59 (10%) yielded non-evaluable results. Analysis by individual bone marrow sites showed an agreement between cytological and immunocytochemical examinations in 276 of 309 (89%) evaluable tests with 5 A7 and in 179 of 210 (85%) with UJ 13 A. Infiltration by neuroblastoma cells was reported in 9% of samples by cytology, in 6% by immunochemistry with 5 A7 and in 16% with 13 A. Analysis of results by staging demonstrated agreement between cytological examination and immunocytochemical detection with both monoclonal antibodies in 60 of 75 (80%) evaluable stagings. Bone marrow metastasis was detected by cytology in 22% of stagings, by immunochemistry with 5 A7 in 23%, with UJ 13 A in 25%. Detailed analysis of discordant results revealed that they were related partly to bone marrow sampling variability associated with focal and minimal metastasis of neuroblastoma cells. These data suggest the clinical usefulness of immunocytochemical detection as a complementary test to cytological examination for accurate evaluation of bone marrow infiltration in patients with disseminated neuroblastoma.

Antibodies, Monoclonal↗

Acute leukaemia with t(4;11) in patients previously exposed to carcinogens.

We report three cases of acute leukaemia with t(4;11) (q21;q23), one of them of undifferentiated and the other two of lymphoid phenotype, occurring after adjuvant radiochemotherapy for breast cancer (two cases) or occupational exposure to radiation (one case). Although the myeloid phenotype and characteristic chromosomal anomalies usually observed in secondary leukaemia were lacking, our observations raise the possibility of causal relationship between exposure to carcinogens and the occurrence of a leukaemia with t(4;11).

Acute Disease↗

The syndrome of abnormal chromatin clumping in leucocytes: a myelodysplastic disorder with proliferative features?

Five patients presenting extremely exaggerated chromatin clumping in leucocytes, associated with a loss of segmentation, are described. Peripheral cytopenia, a high percentage of circulating immature granulocytes (chiefly myelocytes) with variable leucocytosis, marrow hypercellularity with granulocytic hyperplasia and moderate dysplastic changes in erythroblastic and megakaryocytic lines, constitute, together with the granulocytic nuclear anomaly, the characteristic features of the studied cases. Cytogenetic analysis showed a clonal 12p anomaly in one of the three cases available for study. Survival was poor with a median of 15 months, bleeding and infections being responsible for the majority of deaths. All these findings point to abnormal chromatin clumping in leucocytes as the marker of a true entity with both myelodysplastic and myeloproliferative features. We propose that it take its place among myelodysplastic syndromes (MDS) beside chronic myelomonocytic leukaemia (CMML), with which it shares many similarities in clinical and biological behaviour.

Aged↗

B-cell acute lymphoblastic leukaemia: clinical and biological aspects.

Acute lymphoblastic leukaemia of B-cell phenotype (B-ALL) is uncommon. We studied eight cases of B-ALL, investigating the clinical characteristics as well as the biological features. Cytology revealed a typical L3 profile in most cases, but in one case the morphological diagnosis was L2 and morphometric analysis indicated that the blasts in B-ALL were larger than in other ALLs. Cytogenetic study detected the typical translocations (8; 14) and (8; 22) in most of the cases. Abnormalities of the long arm of the chromosome 1 were found in four cases and a major aneuploidy was observed in one case. Cell-cycle analysis showed a high degree of proliferation with, in all cases, a small fraction of cells in G1 with low protein content (corresponding to early G1). All these biological characteristics must be related to the poor prognosis of this disease.

Acute Disease↗

Initial clonal acute lymphoblastic transformation of chronic lymphocytic leukemia with (11;14) and (8;12) chromosome translocations and acquired homozygosity.

A 69-year-old woman presented with chronic lymphocytic leukemia (CLL) diagnosed after bone marrow recovery following intensive chemotherapy for acute lymphoblastic leukemia. The retrospective diagnosis of initial blastic transformation of CLL was made. The patient eventually died, 5 months after initial blastic phase, from a blastic relapse of her CLL. Immunologic and karyotypic studies of the lymphoid cells at different times during the evolution of the disease provided evidence that both the small lymphocytes and the large blastic cells originated from the same clone since they carried the same surface markers and the same (11;14) (q13;q32) translocation. A subpopulation of cells carried in addition a t(8;12) (q24;q22) together with the loss of the normal chromosome 8 and homozygosity for the abnormal der(8). The possibility that this second population might correspond to the blast cells and that the occurrence of the t(8;12) with homozygosity might be linked to blastic transformation of the CLL is discussed.

Aged↗

Effects of recombinant human interleukin-3 on CD34-enriched normal hematopoietic progenitors and on myeloblastic leukemia cells.

Induction of proliferation and differentiation in response to recombinant human interleukin-3 (hIL-3) was studied in liquid and semisolid cultures of umbilical cord blood and bone marrow cells that were fractionated by "panning" with anti-My10 antibody according to expression of CD34 antigen. Cells from enriched fractions (70% to 90% CD34+) were found to proliferate strongly in response to hIL-3. Phenotypic analysis and morphologic characterization of the proliferating cells demonstrated a rapid decrease in CD34+ cells and an exponential increase in the number of cells belonging to the neutrophilic, eosinophilic, monocyte/macrophage, and thrombocytic lineages. When combined with recombinant human erythropoietin, burst colonies and cells expressing glycophorin-A were detected, thereby demonstrating the effects of hIL-3 on erythroid progenitors. Further, the development of mixed-erythroid colonies indicated that multipotential cells within CD34-enriched fractions responded to hIL-3. In addition, we examined the effect of hIL-3 on the proliferation of primary acute myeloblastic leukemia cells in liquid culture. We found that hIL-3 was able to induce cell proliferation in a proportion of the cases tested. Heterogeneity of the responses to hIL-3 was in part related to French-American-British classification but could not be correlated with CD34 antigen expression by the leukemic cells. These results indicate that, although the effects of hIL-3 on proliferation and differentiation of cells obtained from normal hematopoietic specimens were primarily borne by CD34+ cells, expression of the CD34 molecule per se is an insufficient condition to determine a growth response to this lymphokine.

Antigens, CD34↗