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G Delsol

Publications and source records attributed to G Delsol.

At least 91 records · Page 5Linked to original sources
PubMed1997

Detection of anaplastic lymphoma kinase (ALK) and nucleolar protein nucleophosmin (NPM)-ALK proteins in normal and neoplastic cells with the monoclonal antibody ALK1.

The t(2;5)(p23;q35) translocation, associated with anaplastic large-cell lymphoma (ALCL), results in the production of the nucleolar protein nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) protein. This report describes an immunocytochemical study of the distribution of ALK and NPM-ALK proteins using a new monoclonal antibody, ALK1, that recognizes a formalin resistant epitope in both the 80-kD NPM-ALK chimeric and the 200-kD normal human ALK proteins. Cytoplasmic and nuclear labeling was seen in the t(2;5)+ SU-DHL-1 and Karpas 299 cell lines. Normal ALK protein expression was restricted to the central nervous system (in scattered neurons, glial cells, and endothelial cells). Two hundred and thirty-nine cases of lymphoma and 80 nonhematopoietic tumors were immunostained. Antibody ALK1 labeled 53.4% (39 of 73 cases) of CD30+ ALCL. A case of ALCL with a t(1;2) translocation was ALK1+. Three cases of CD30- ALCL with prominent nucleoli showed a unique pattern of coarse granular cytoplasmic labeling. All other tumors, including Hodgkin's disease and lymphomatoid papulosis, were ALK1-. These results indicate that reliable immunostaining of routine biopsy material for NPM-ALK and ALK proteins is feasible. Such analysis is of diagnostic importance, especially because t(2;5)+ ALCL cases have a good prognosis with appropriate treatment.

Adolescent↗
PubMed1997

Telomerase activity in reactive and neoplastic lymphoid tissues: infrequent detection of activity in Hodgkin's disease.

We used the recently described sensitive and rapid detection assay called telomeric repeat amplification protocol (TRAP) to detect telomerase activity in lymphoblastoid (n = 5) and lymphoma cell lines (n = 7), hyperplastic lymph nodes (n = 6) and tonsils (n = 5), and tissues involved by non-Hodgkin's lymphoma (NHL) (n = 43) and Hodgkin's disease (HD) (n = 14). Clearly evident telomerase activity was found in all lymphoblastoid and lymphoma cell lines, and in 34 of 43 cases (80%) of NHL. These results were expected because of the proliferative and immortal nature of the cell lines and most malignant cells. However, positive results were obtained with the TRAP assay in all hyperplastic lymph nodes and tonsils, which raises the issue of derepression of telomerase activity during an immune response. Telomerase activity alone therefore does not distinguish malignant lymphoid proliferations from reactive states. Telomerase activity was detected in only 1 of 14 cases (7%) of lymphoid tissues involved by HD. Eight of the 13 negative cases were considered to be interpretable because of the lack (3 of 13 cases) or low level (5 of 13 cases) of telomerase inhibition. The five remaining cases could not be evaluated because of their telomerase inhibitor content. The findings imply either transient or very low levels of telomerase activity in HD or that HD for the greater part is a telomerase-independent neoplasm. Microdissection studies are needed to identify subsets of cells carrying telomerase activity in both reactive and neoplastic lymphoid tissues.

Chromosomes, Human↗
PubMed1997

IgH and TcR-gamma gene rearrangements identified in Hodgkin's disease by PCR demonstrate lack of correlation between genotype, phenotype, and Epstein-Barr virus status.

Analysis of IgH and TcR-gamma genes using consensus primers identifying junctional regions of rearranged genes by polymerase chain reaction (PCR) was performed on tissues involved by Hodgkin's disease (HD) in 90 cases and was correlated with the immunophenotype of Hodgkin and Reed-Sternberg (HRS) cells and the presence of Epstein-Barr virus (EBV) within these cells. Clonal IgH gene rearrangements were found in 1/5 cases of lymphocyte predominance (LP) subtype and none was positive for EBV. In 85 cases of classic HD, no IgH or TcR-gamma gene rearrangements were found in 51 (60 per cent) cases. A similar percentage, but not the same cases, were of null (non-B, non-T) phenotype. Of 30 cases where a B phenotype was assigned to HRS cells, nine had IgH gene rearrangements, three had TcR-gamma gene rearrangements, and two had both genes rearranged. None of the five cases assigned to T phenotype of HRS cells showed rearrangement of TcR-gamma genes, but two cases showed rearranged IgH genes. Among 41 cases of null phenotype, ten had IgH gene rearrangements, five had TcR-gamma gene rearrangements, and three cases had both genes rearranged. Whereas EBV was detectable in HRS cells in 17/43 classic HD cases of assigned B phenotype, EBV was also detectable in 2/5 cases of assigned T phenotype and in 21 cases with the null phenotype. Furthermore, there was no correlation of EBV with the presence or lack or IgH or TCR-gamma gene rearrangements. Of the remainder, half (30 per cent) expressed antigens associated with lymphocytes without an appropriate genotype. The results confirm lymphocyte-lineage committed cells at the origin of HRS cells in 40 per cent of cases. Any hypothesis of a non-lymphocytic origin of HRS cells will require the inducibility of CD30 on candidate precursors and the methodology for probing genetic events in such cells to be addressed.

Gene Rearrangement, gamma-Chain T-Cell Antigen Rec↗
PubMed1997

Epstein-Barr virus in B-cell lymphomas associated with chronic suppurative inflammation.

Chronic antigenic stimulation is considered to play an important role in neoplastic lymphoid transformation. This paper describes three cases of non-Hodgkin lymphomas (NHLs) associated with long-standing chronic suppuration. Two were primary bone lymphomas associated with long-standing chronic osteomyelitis and one was a primary skin lymphoma associated with chronic venous ulcers with a latent period of 13 years. All were diffuse large B-cell lymphomas, with plasmacytoid differentiation in two cases. Epstein-Barr virus (EBV)-encoded RNAs were demonstrated in virtually all tumour cells in all cases by in situ hybridization. Immunohistochemistry revealed EBV-encoded latent membrane protein (LMP)-1 expression in one case and BZLF1 protein expression in all three cases, whilst the EBV-encoded nuclear antigen (EBNA)-2 was not detected. Kaposi's sarcoma-associated herpesvirus (KSHV) sequences were absent in two cases studied. Our cases show similarities with pyothorax-associated pleural lymphomas reported mainly from Japan and recently from France, which are invariably associated with EBV. These findings suggest a causal effect of EBV in the development of this type of lymphoma complicating long-standing chronic suppuration. Localized immunodepression induced by chronic inflammation or immunosuppressive cytokines may favour the clonal proliferation of EBV-infected B cells.

Aged↗
PubMed1997

Polymerase chain reaction on cerebrospinal fluid cells in the detection of leptomeningeal involvement by B-cell lymphoma and leukaemia: a novel strategy and its implications.

In the search of B-cell lymphoma/leukaemia dissemination to cerebrospinal fluid (CSF), we used the highly sensitive semi-nested PCR (snPCR) for the analysis of IgH gene rearrangements. This method detects a rearranged IgH gene from a single B lymphocyte which may or may not represent the neoplastic B-cell population. We therefore performed multiple snPCR (three to five) experiments on the same CSF sample, postulating that the detection of a band of the same size and sequence in different PCR runs was highly indicative of a clonal population. 17 consecutive cases with a differential diagnosis of primary (PCNSL) (n=10) or secondary (SCNSL) (n=7) CNS lymphoma or leukaemia were investigated by the new strategy. The clonal nature of the B-cell population was confirmed in 3/10 of suspected PCNSL, and in six other cases the PCR study was indicative of reactive lymphocytosis. One case revealed a clonal B-cell population in the clinical context of an autoimmune disorder. Evidence of clonal B-cell population was found in 4/7 of suspected SCNSL. In one of these cases the detected band and its sequence proved identical to that of the primary nodal lymphoma. We believe that the evaluation of B-cell clonality in CSF requires multiple snPCR amplification on the same sample to compare the size of the products and, if necessary, the DNA sequences to ascertain the diagnosis of malignancy in equivocal cytologic and clinical findings.

Adult↗
PubMed1997

Expression and signal transduction of T-cell antigen receptor (TCR)/CD3 complexes on fresh or in vitro expanded T lymphocytes from patients with Hodgkin's and non-Hodgkin's lymphomas.

T-cell responses against soluble antigens, alloantigens and mitogens are frequently diminished in patients with certain types of cancer. In the present study, the authors investigated possible mechanisms for the partial T-cell immunodeficiency in patients with Hodgkin's or non-Hodgkin's lymphomas. It was found that T-cells from lymphoma patients had significantly reduced proliferative responses to EBV-transformed B-cell lines and to anti-TCR/CD3 MoAb; a 30-50% reduction of cells expressing membrane T-cell receptor (TCR) complexes; and a significantly reduced signal transduction function. Long-term in vitro culture conditions were developed to expand T cells in TCR/CD3-dependent or TCR/CD3-independent manners. With such methods, it was found that the decreased T-cell responses in patients with Hodgkin's and non-Hodgkin's lymphomas appeared to be an intrinsic T-cell defect (not at the antigen presenting cell level), and the T-cell responses could be recovered after only a few days in culture. Thus, it is suggested that the T-cell response-defect in Hodgkin or non-Hodgkin lymphoma patients is a reversible phenomenon, dependent on the patient's tumour-bearing environment.

B-Lymphocytes↗
PubMed1997

Anaplastic large cell lymphoma of maternal origin involving the placenta: case report and literature survey.

Non-Hodgkin's lymphoma (NHL) occasionally involves the placenta, and information of such occurrence should be useful for management of the mother and fetus. We report the first case of anaplastic large cell lymphoma (ALCL) disseminated to the placenta. The diagnosis was made via excisional biopsy of cervical lymphadenopathy in a 20-year-old woman at 27 weeks' gestation. Involvement of the placenta was noted on gross examination after cesarean section delivery of a girl at 30 weeks' gestation. The ALCL was microscopically confined to intervillous spaces in a manner similar to previous reports of other NHLs. The immunophenotype was characteristic (CD30+, EMA+, BNH9+), and the now frequently associated t(2;5)(p23;q35) translocation with this lymphoma was detected by the recently produced monoclonal antibody ALK1 against the nucleophosmin/anaplastic lymphoma kinase (NPM/ALK) chimeric protein. Complete remission was induced in the mother after delivery. Both mother and child are healthy at 10 years' follow-up. The case is reported in light of the sparse literature on lymphomatous involvement of the placenta.

Adult↗
PubMed1997

Reed-Sternberg cells and "bystander" lymphocytes in lymph nodes affected by Hodgkin's disease are infected with different strains of Epstein-Barr virus.

In most cases of Epstein-Barr virus (EBV)-associated Hodgkin's disease (HD), EBV-positive Reed-Sternberg (RS) cells and rare EBV-positive reservoir lymphocytes coexist in lymph nodes. Here we show that, in two cases of EBV-associated HD, strains infecting RS cells and reservoir lymphocytes of the same patient have different BNLF-1 genes. This suggests that RS cells and reservoir lymphocytes of the same patient are infected by different EBV strains.

Animals↗
PubMed1997

Telomerase activity in human thyroid carcinomas originating from the follicular cells.

Telomerase activity is known to be absent from most normal and well-differentiated tissues, although being detectable in the vast majority of malignant tumors. An increasing number of reports demonstrate that telomerase may be activated in benign tumors, such as adenomas. We have investigated a series of normal and neoplastic thyroid tissues for the presence of telomerase activity. As expected, all normal thyroid tissues (n = 20) had no display of telomerase activity. Amongst cancers, the incidence of telomerase activity varied with the histological subtypes. Telomerase activity was present in only 3/15 cases (20%) of papillary carcinomas. Telomerase activity was more frequently detected in follicular (4/6) and in undifferentiated (2/3) carcinomas. Unexpectedly, one case (1/12) of adenoma contained high levels of telomerase activity. Taken together, these results indicate that telomerase may play some role in the pathogenesis of thyroid tumors, in particular in follicular and undifferentiated carcinomas that are known to have the most aggressive behavior.

Adenocarcinoma, Follicular↗
PubMed1997

CNA.42, a new monoclonal antibody directed against a fixative-resistant antigen of follicular dendritic reticulum cells.

A new monoclonal antibody (MAb), CNA.42, was generated using the CEM T-cell line. It recognizes a 120-kd formalin-resistant glycosylated antigen that is mainly expressed by follicular dendritic reticulum cells (FDRCs). This antigen is also expressed by a few mononuclear cells in the paracortical area of reactive lymph nodes and by some cortical thymocytes. Two hundred and eighty-nine cases of hematopoietic tumors of various types were tested with this antibody. They showed either intact FDRC networks or FDRC networks dispersed among malignant cells. In follicular lymphomas, the follicular pattern was highlighted by CNA.42 MAb. Expanded FDRC networks were found in angioimmunoblastic T-cell lymphomas. Neoplastic cells were positive in 43.6% (24/55) of T-cell and 4.6% (6/129) of B-cell lymphomas. The highest percentage of cases with positive neoplastic cells was found in anaplastic large-cell lymphomas (62.5%; 15/24). In Hodgkin's disease, FDRC networks, sometimes encasing Hodgkin and Reed-Sternberg (HRS) cells, were found. HRS cells were also stained by this antibody in 23 (21.9%) of the 105 cases examined. A variety of normal nonlymphoid tissues and nonhematopoietic tumors, such as some neurogenic tumors, carcinoma, and occasional sarcomas, were found to be positive. Analysis of the reactivity of CNA.42 antibody with FDRCs of lymphoid tissue from different animal species showed similar reactivity to that observed in humans, suggesting widespread evolutionary conservation of the antigen recognized by this antibody. In daily diagnostic practice, CNA.42 MAb seems to be a suitable FDRC marker and possibly has an auxiliary role in recognizing T-cell lymphomas.

Animals↗
PubMed1997

[Techniques for detection of telomerase activity in tissue samples. Diagnostic and prognosis importance].

Telomerase activation has been shown to be an almost universal property of malignant tumors evoking its role in the immortalisation process. We used the recently described sensitive and rapid detection assay called telomeric repeat amplification protocol (TRAP) to detect telomerase activity in neoplastic and non neoplastic tissues. Human telomerase is a ribonucleoprotein which functions as a telomere terminal transferase by adding multiple repeats of the TTAGGG hexamer at the 3'-OH ends of either telomeres or oligonucleotide specifically designed for the TRAP assay. Whenever present, telomerase activity is revealed on acrylamide gel by a six nucleotide ladder of extension products. Detection of telomerase activity may be evaluated for differentiating neoplastic from non neoplastic tissues. In addition, quantitation of telomerase activity may serve as prognostic marker for malignant tumors.

Autoradiography↗
PubMed1997

The interface of Hodgkin's disease and anaplastic large cell lymphoma.

We reviewed 18 cases in which morphology was intermediate between Hodgkin's disease (HD) and anaplastic large cell lymphoma (ALCL). Eight cases exhibited the usual CD30+, CD15+/-, null cell phenotype of classic HD but were rich in neoplastic cells with sinusoidal infiltrating pattern. In this group, there was no expression of antigens (EMA, BNH9, CBF78) associated with ALCL, and only two were positive for Epstein-Barr virus (EBV). Ten EBV negative cases fit the description of HD like ALCL by variable expression of antigens unassociated with HD. EMA was clearly and strongly expressed in all ten, whereas antigens recognized by BNH9 and CBF78 were expressed in four and three cases, respectively. Focal expression of CD45 and CD43 was observed in half of these cases. In only one case was the t(2.5) translocation detected with the new monoclonal antibody, ALK1. Therefore, the expression of EMA, BNH9 and CBF78, often in concert without CD15 and without the specific translocation, appears currently to be the most probable phenotype and genotype of HD like ALCL. There was a tendency for aggressive behaviour of the disease considered HD like ALCL. Whether such patients will benefit from a therapeutic strategy that takes into account both phenotype and genotype remains to be discovered.

Hodgkin Disease↗
PubMed1996

Epstein-Barr virus (EBV)-associated lymphoproliferations in severe combined immunodeficient mice transplanted with Hodgkin's disease lymph nodes: implications of EBV-positive bystander B lymphocytes rather than EBV-infected Reed-Sternberg cells.

To establish an in vivo model for the study of Hodgkin's disease and Reed-Sternberg (RS) cells, 25 lymph node tissue samples involved by Hodgkin's disease were grafted into severe combined immunodeficiency (SCID) mice. Ten Epstein-Barr virus (EBV)-associated tumors were obtained in SCID mice. EBV-positive tumors growing in SCID mice were correlated with the presence of EBV-positive nonneoplastic B cells in patient tumors (90% v 26.6%; P<.01) and was independent of the EBV status of RS cells. Our results suggested that EBV-positive tumors growing in SCID mice originated from normal EBV-positive small lymphocytes (bystander B lymphocytes). We also compared the characteristics of these tumors with those obtained after transplantation of 15 non-Hodgkin's lymphoma and four reactive lymph nodes. The latent period to observe a growing tumor in SCID mice was similar between the two groups (12.86 +/- 5.59 weeks for Hodgkin's disease v 13.6 +/- 5.36 weeks for non-Hodgkin's lymphoma and reactive lymph nodes). The relatively high number of EBV-positive small lymphocytes detected in Hodgkin's disease and T-cell lymphoma compared with B-cell lymphoma may account for the greater percentage of EBV-positive tumors obtained in SCID mice. Our results show that SCID mice do not provide the growth conditions that are required for in vivo growth of RS cells. We noted in some SCID tumors, the presence of binucleated and/or multinucleated giant cells resembling RS cells. However, the presence of such cells was not restricted to mice grafted with lymph nodes involved by Hodgkin's disease. We postulate that in previous reports, cells resembling RS cells were just binucleated EBV-positive lymphoma blastoid cells rather than actual RS cells.

Adult↗
PubMed1996

Frequent expression of the cell death-inducing gene Bax in Reed-Sternberg cells of Hodgkin's disease.

The expression of a cell death-inducing gene, Bax, was investigated in 52 cases of Hodgkin's disease in parallel with Epstein-Barr virus and was compared with the immunodetection of other apoptosis-regulating proteins, Mcl-1, Bcl-2, and Bcl-x. Bax immunostaining was found in 92% of the cases, among them 28% with a strong signal in more than 75% of the Reed-Sternberg cells. Mcl-1 was positive in 80% of the cases, whereas Bcl-2 and Bcl-x were found in 53% and 88% of the cases, respectively. Of 48 (89%) Bax-positive tumors, 43 were found to express apoptosis-inhibiting proteins such as Mcl-1 or Bcl-2. With the exception of 1 case, all Bax-positive tumors also expressed either Bcl-2, Bcl-x, Mcl-1, or combinations of these anti-apoptotic proteins. No correlation was found between Bax expression and the presence of apoptotic cells as detected by morphology and the in situ 3' OH-DNA end-labeling technique. Our findings show that the apoptosis-inducing gene Bax expression is frequently expressed in Hodgkin's disease, providing a potential explanation for the good chemoresponses generally obtained for patients with this neoplastic disorder.

Apoptosis↗
PubMed1996

Hodgkin's disease after transplantation.

Hodgkin's disease (HD) has seldom been reported after transplantation. Epstein-Barr virus (EBV) is present in about 50% of Reed-Sternberg cells in HD developing in immunocompetent individuals, but is more frequently found in HD of acquired immune deficiency syndrome patients. We report 7 cases of HD that occurred in transplant recipients. Clinical and pathological data and studies of EBV reveal specific features of HD after transplantation. Six patients received kidney transplants and 1 patient received combined kidney and pancreas transplantation. Immunosuppressive therapy consisted of cyclosporine, steroids, azathioprine, and antilymphocyte globulins. One patient received, in addition, anti-CD3 mAb therapy and an EBV+ B cell lymphoma developed. Retrospective EBV serological data from patients were collected. Tumors were classified according to pathology. EBV studies were conducted by immunohistochemical methods with monoclonal antibodies to EBV-latent membrane protein (LMP) or EBV-nuclear antigen 2 (EBNA2), and by in situ hybridization for latent nuclear EBV-early RNAs (EBERs). The mean lapse of time between transplantation and HD was 49 months. Six patients presented with enlarged lymph nodes and 1 patient presented with liver involvement. HD was classified as IA in 2 patients, IIA in 3 patients, IIIB in 1 patient, and IVB in 1 patient. Four patients had primary EBV infection after graft, before HD, and the others reactivated latent EBV infection. Histological subtypes were mixed cellularity in 6 cases and lymphocytic depletion in 1 case. Latent EBV infection was detected with EBERs in all tumors. Reed-Sternberg cells expressed LMP, and were negative for EBNA2 expression. Six patients were treated: 2 patients at stage I received radiotherapy, and relapsed within 1 year with a more advanced stage of HD; chemotherapy was indicated as primary therapy in 5 patients, and as salvage therapy in 2 patients; it was associated with radiotherapy in 4 patients. Immunosuppressive therapy was reduced in all patients. Four patients were alive and in complete remission 18, 25, 31, and 67 months after chemotherapy, with a functioning graft in 3 patients. Two patients died of infection. Mixed cellularity is the most frequent histological subtype observed in HD occurring in transplant patients. EBV is present in all Reed-Sternberg cells. Posttransplant HD shows similarities with human immunodeficiency virus-associated HD. These facts argue for a role of EBV infection and immunosuppression in the progression of HD after transplantation.

Adolescent↗
PubMed1996

High incidence of the t(2;5)(p23;q35) translocation in anaplastic large cell lymphoma and its lack of detection in Hodgkin's disease. Comparison of cytogenetic analysis, reverse transcriptase-polymerase chain reaction, and P-80 immunostaining.

Fifty-six cases of anaplastic large cell lymphoma (ALCL), 23 cases of Hodgkin's disease, and 16 cases of diffuse large cell lymphoma were investigated for the t(2;5)(p23;q35) translocation. The translocation was detected by using cytogenetic analysis, reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry with P80 antibody directed against the kinase domain of anaplastic lymphoma kinase (ALK) of the chimeric NPM/ALK protein. In all but three cases of ALCL, we found an agreement between cytogenetic analysis, RT-PCR, and P80 staining. However, in one case, the t(2;5) translocation was detected with cytogenetic analysis, but RT-PCR and P80 staining were found to be negative. Conversely, in another case the karyotype was normal, but the hybrid mRNA and P80 staining were found to be positive. In one case, malignant cells showed a translocation involving chromosomes 1q25 and 2p23 and were strongly positive for P80 staining. Such a result could be expected because P80 antibody detects the kinase domaine of the ALK protein encoded by chromosome 2p23. Overall 73.2% (41 of 56) of cases were found to be positive. However, the highest percentage (23 of 26 cases; 88.5%) of P80 positive cases was found in children compared with 60% (18 of 30 cases) in adult ALCL (P < .05). In Hodgkin's disease, Reed-Sternberg cells were found to be clearly negative by RT-PCR and with P80 antibody. The latter results suggest that Hodgkin's disease and t(2;5)-positive ALCL are distinct biological entities and that the demonstration of the t(2;5) translocation is of diagnostic importance in differentiating these two entities. The results of the present study indicate that immunohistochemistry with P80 antibody is a reliable method for detecting NPM/ALK chimeric protein.

Adolescent↗