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G Salles

Publications and source records attributed to G Salles.

At least 55 records · Page 3Linked to original sources
PubMed2000

Mucosa-associated lymphoid tissue lymphoma is a disseminated disease in one third of 158 patients analyzed.

Mucosa-associated lymphoid tissue-derived lymphoma (MALT lymphoma) is usually a very indolent lymphoma, described as localized at diagnosis and remaining localized for a prolonged period; dissemination occurs only after a long course of evolution. In our database, out of 158 patients with MALT lymphoma, 54 patients presented with a disseminated disease at diagnosis. Of these 54 patients, 17 patients (30%) presented with multiple involved mucosal sites; 37 patients (70%) presented with 1 involved mucosal site, but in 23 of these patients (44%), dissemination of the disease was due to bone marrow involvement; 12 patients (22%) had multiple lymph node involvement; and 2 patients (4%) had nonmucosal site involvement. No significant difference in clinical characteristics (sex, age, performance status, B symptoms) and biological parameters (hemoglobin [Hb] and lactate dehydrogenase levels) was observed between localized or disseminated MALT-lymphoma patients. Only beta2-microglobulin level was significantly more elevated in disseminated disease patients than in localized disease patients. Complete response after the first treatment was achieved in 74% of the patients, and there was no difference between the 2 groups. With a median follow-up of 4 years, the estimated 5- and 10-year overall survival rates were similar in the 2 groups, 86% and 80%, respectively. The median freedom-from-progression survival was 5.6 years for all patients, surprisingly without any difference between localized and disseminated MALT-lymphoma patients. In conclusion, MALT lymphoma is an indolent disease but presents as a disseminated disease in one-third of the cases at diagnosis. The dissemination does not change the outcome of the patients.

Adult↗
PubMed2000

Expression of genes coding for the tumor necrosis factor and lymphotoxin ligand-receptor system in non-Hodgkin's lymphomas.

Excessive production of the tumor necrosis factor (TNF) ligand-receptor system has been found to contribute to the severity of non-Hodgkin's lymphoma (NHL). We therefore investigated the expression of TNF, lymphotoxin alpha (LTalpha), lymphotoxin beta (LTbeta), and their receptor (p55, p75, LTbeta-R) transcripts within the tumor tissue in different NHL histological subtypes. The constitutive expression of genes coding for TNF-related ligands and receptors was found in almost all 31 NHL samples studied. Semi-quantitative reverse transcription/polymerase chain reaction and computed densitometry assays revealed that the amounts of TNF, LTalpha, p55, and LTbeta-R mRNA were higher in follicular NHL than in other histological entities. Therefore tumor cell immunopurification was performed in representative follicular NHL samples and consistent results were obtained. The pattern of LTbeta gene expression was different from that of the other molecules, indicating the existence of distinct mechanisms of gene regulation. These results indicate that the transcription of genes coding for the TNF ligand-receptor system in NHL tumor tissue is more widespread than originally thought and that the heterogeneity of their expressions might be related to histological features. The expression of TNF-related ligands and receptors in tumor tissues is likely to contribute to the clinicopathological features of lymphoid-derived malignancies.

Adult↗
PubMed2000

Transplantation with selected autologous peripheral blood CD34+Thy1+ hematopoietic stem cells (HSCs) in multiple myeloma: impact of HSC dose on engraftment, safety, and immune reconstitution.

OBJECTIVE: The aims of our study performed in myeloma were to evaluate the performance and the safety of Systemix's high-speed clinical cell sorter, to assess the safety and efficacy of deescalating cell dose cohorts of CD34+Thyl+ hematopoietic stem cells (HSCs) as autologous grafts by determining engraftment, and to assess the residual tumor cell contamination using polymerase chain reaction (PCR) amplification assays of patient-specific complementarity determining region III (CDR III) analysis for residual myeloma cells. MATERIALS AND METHODS: The clinical trial was performed in 31 multiple myeloma patients, using purified human CD34+Thyl+ HSCs mobilized from peripheral blood with cyclosphosphamide and granulocyte-macrophage colony-stimulating factor to support a single transplant after high-dose melphalan 140 mg/m2 alone (cohort 1) and with total body irradiation (TBI) (cohorts 2-5) after an HSC transplant cell dose de-escalation/escalation design. RESULTS: Twenty-three patients were transplanted. Engraftment data in the melphalan + TBI cohorts confirmed that HSC doses above the threshold dose of 0.8 x 10(6) CD34+Thy1+ HSCs/ kg provided prompt engraftment (absolute neutrophil count >0.5 x 10(9)/L day 10; platelet count >50 x 10(9)/L day 13). A higher rate of infections was observed in the early and late follow-up phases than usually reported after CD34+ selected or unselected autologous transplantation, which did not correlate with the CD34+Thy1+ HSC dose infused. Successful PCR for CDR III could only be performed in five patients on initial apheresis product and final CD34+Thy1+ HSC product and showed a median tumor log reduction >3.12. CONCLUSIONS: CD34+Thy1+ HSCs are markedly depleted or free of detectable tumor cells in multiple myeloma and are capable of producing fast and durable hematopoietic reconstitution at cell doses >0.8 x 10(6) CD34+Thy1+ HSCs/kg. The delayed immune reconstitution observed is not different from that described in unselected autologous bone marrow and peripheral blood mononucleated cells transplants in multiple myeloma and may be corrected by addition of T cells either to the graft or to the patient in the posttransplant phase.

Adult↗
PubMed2000

A prospective study of intensive induction therapy with high-dose consolidation in patients with aggressive non-Hodgkin's lymphoma and two or three adverse prognostic factors.

Patients with NHL and two or three factors of the International Prognostic Index (IPI) have a poor prognosis. We performed a prospective trial of intensive induction therapy followed with high-dose consolidation in such patients to determine the feasibility of this approach, as well as the response rate and survival. Untreated patients with aggressive lymphoma under the age of 60 with two or three adverse prognostic factors (disseminated stage, increased serum LDH, ECOG performance status >1) were prospectively included between June 1995 and April 1998 in a trial evaluating intensive induction chemotherapy with the ACE regimen (adriamycin day 1; cyclophosphamide days 1-2; etoposide days 1-3), with G-CSF support. Patients in complete remission after induction received one course of intensification with stem cell support (BEAM regimen), whereas patients in partial response received two intensifications (BEAM, then ICE regimens). Thirty-three patients (median age 38 years) were included. All patients presented WHO grade 4 leukopenia and 84% grade 3-4 thrombocytopenia during induction. There was one toxic death during induction. Twenty-nine patients proceeded to high-dose consolidation, including 12 patients who received a second high-dose treatment. The overall response rate was 88% (95% CI 76-99%), both after induction therapy and treatment completion. Thirty-nine percent of the patients had achieved complete remission after induction, and 73% after treatment completion. With a median follow-up after treatment onset of 29 months, the projected 3-year overall survival was 71% (95% CI 64-78%) and the event-free survival 58% (95% CI 50-66%). Event-free survival was significantly shorter in patients who did not achieve CR after induction therapy or after treatment completion. Early therapeutic intensification after intensive induction chemotherapy is feasible in patients with poor prognosis aggressive NHL and shows promising response and survival rates.

Adolescent↗
PubMed2000

Survival benefit of high-dose therapy in poor-risk aggressive non-Hodgkin's lymphoma: final analysis of the prospective LNH87-2 protocol--a groupe d'Etude des lymphomes de l'Adulte study.

PURPOSE: To present the final analysis, with a median follow-up of 8 years, of the LNH87-2 randomized study, which compares consolidative sequential chemotherapy (ifosfamide plus etoposide, asparaginase, and cytarabine) with high-dose therapy (HDT) using cyclophosphamide, carmustine, and etoposide (CBV regimen) followed by stem-cell transplantation in patients with aggressive non-Hodgkin's lymphoma in first complete remission after induction, focusing on high/intermediate- and high-risk patients identified by the age-adjusted international prognostic index. PATIENTS AND METHODS: Among the 916 eligible patients, 451 presented with two (n = 318) or three (n = 133) risk factors. After reaching complete remission to induction therapy, 236 of these higher risk patients were assessable for the consolidation phase, with 125 patients in the HDT arm and 111 in the sequential chemotherapy arm. RESULTS: Among these 451 higher risk patients, 277 (61%) achieved complete remission after induction treatment. In the population of 236 randomized patients, HDT was superior to sequential chemotherapy, with 8-year disease-free survival rates of 55% (95% confidence interval [CI], 46% to 64%) and 39% (95% CI, 30% to 48%), respectively (P =.02; relative risk, 1.56). The 8-year survival rate was significantly superior in the HDT arm (64%; 95% CI, 55% to 73%) compared with the sequential chemotherapy arm (49%; 95% CI, 39% to 59%) (P =.04; relative risk, 1.51). CONCLUSION: On the basis of the final analysis of this prospectively treated series of patients, retrospectively analyzed on the basis of the International Prognostic Index, we hypothesize that HDT benefits patients at higher risk who achieve complete remission after induction treatment.

Adult↗
PubMed2000

Factors that predict chemotherapy-induced myelosuppression in lymphoma patients: role of the tumor necrosis factor ligand-receptor system.

PURPOSE: To analyze factors that predict the occurrence of chemotherapy-induced myelosuppression and, in particular, the role of the tumor necrosis factor (TNF) ligand-receptor system in lymphoma patients at the beginning of their treatment. PATIENTS AND METHODS: We investigated the predictive factors for myelosuppression after the first course of chemotherapy in a cohort of 101 consecutive, previously untreated lymphoma patients receiving regimens that include doxorubicin and cyclophosphamide. Plasma samples were tested at baseline by enzyme-linked immunosorbent assay for TNF and its soluble receptors. Univariate and multivariate analyses were performed with a forward regression procedure that included all of the parameters that were found to be significant in the univariate analysis. The dose of chemotherapy and the prophylactic treatment with granulocyte colony-stimulating factor were deliberately included in this model. RESULTS: Sixty-seven patients experienced World Health Organization (WHO) grade 4 neutropenia, and 37 patients experienced febrile neutropenia, which was responsible for WHO grade 2 through 4 infections in 23 patients. In multiparametric regression analysis, the occurrence of grade 4 neutropenia was associated with high doses of cyclophosphamide (odds ratio ¿OR, 19.8; P =.008) and high levels of soluble p75-R-TNF (OR, 8.52; P =.001). The duration of grade 4 neutropenia for more than 5 days was associated with the lack of hematopoietic growth factor administration (OR, 6.76; P =.004) and high levels of soluble p75-R-TNF (OR, 5.84; P =.0023). The occurrence of febrile neutropenia was associated with high doses of cyclophosphamide (OR, 4.7; P =.007), altered performance status (OR, 18.8; P <.0001) and high levels of soluble p75-R-TNF (OR, 3.49; P =.029). CONCLUSION: This study indicates that in addition to the dose of chemotherapy and the administration of hematopoietic growth factors, poor performance status and high p75-R-TNF levels can predict the occurrence of chemotherapy-induced myelosuppression in lymphoma patients. This model may help in selecting patients for prophylactic growth factor administration.

Adult↗
PubMed1999

Long term outcome of patients with hairy cell leukemia treated with pentostatin.

BACKGROUND: With the introduction of new drugs such as interferon-alpha (IFN) and purine analogs, the management of hairy cell leukemia (HCL) patients has changed. However, pentostatin has been found to produce higher complete remission rates than IFN. The current study was undertaken to investigate response and long term follow-up in HCL patients treated with pentostatin. METHODS: Between March 1989 and October 1996, 49 patients with HCL and 1 patient with a HCL variant were treated with pentostatin. Eighteen patients had received no prior therapy, 31 patients had received prior treatment with IFN, and 1 patient had received prior treatment with 2'-chlorodeoxyadenosine (2'CdA) and IFN. All patients except 1 were treated with a dose of 4 mg/m2 every 2 weeks. The median number of cycles was 12. RESULTS: The overall response rate was 96% (48 of 50 patients); 22 patients (44%) achieved a complete response, 18 patients (36%) achieved a good partial response (defined as residual bone marrow infiltration < 5%), 8 patients (16%) achieved a partial response, and 2 patients died. For a median follow-up of 33 months off therapy, there were 5 recurrences between 12-66 months; 3 of these patients were treated further with and responded to 2'CdA and 2 died of disease progression at 12 and 40 months, respectively. In addition, 3 patients died of unrelated causes (1 of very early infection, 1 of toxic death and another of cardiac arrest) comprising an overall death rate of 14% (7 of 50 patients). The overall survival rate was 86% for a median follow-up of 38 months (range, 8-105 months). Major side effects were febrile episodes, herpes zoster, nausea/emesis, and pancytopenia. CONCLUSIONS: This analysis confirms both the high remission rate and durable responses that may be achieved with pentostatin treatment in HCL patients. Although pentostatin is active, the risk of cytopenia and immunosuppression must be evaluated carefully.

Adult↗
PubMed1999

Distinct chromosome 3 abnormalities in persistent polyclonal B-cell lymphocytosis.

Persistent polyclonal B-cell lymphocytosis (PPBL) is a rare entity of unknown etiology characterized by a polyclonal expansion of B-lymphocytes with typical bilobulated forms, elevated serum IgM, and an additional isochromosome for the long arm of chromosome 3 as the sole change. In the present study, we investigated four cases of PPBL by means of conventional cytogenetic analysis and FISH. In all patients, the polyclonality of the lymphoproliferation was demonstrated by immunophenotypic studies, and PCR analysis failed to demonstrate clonal IGH rearrangements in three evaluated cases. In two patients, in addition to +i(3)(q10), banding techniques identified unrelated clones with trisomy 3. FISH studies using a chromosome 3 long arm-specific probe provided evidence that all cases had both +i(3)(q10) and +3. To determine more precisely the distribution of the chromosomal abnormalities within the peripheral lymphocyte population, we investigated two of these cases using a technique of simultaneous fluorescence immunophenotyping and interphase cytogenetics (FICTION). We demonstrated that both abnormalities were randomly distributed among the B-lymphocytes, independently of the kappa or lambda light chain isotype and the nuclear aspect. These data lead us to conclude that trisomy 3 represents, in addition to +i(3)(q10), another recurrent cytogenetic change in PPBL, suggesting that this lymphoproliferative disorder is associated with an increased frequency of chromosome 3 instability.

Adult↗
PubMed1999

Infections following peripheral blood progenitor cell transplantation for lymphoproliferative malignancies: etiology and potential risk factors.

PURPOSE: We sought to describe the infections that occur after large-dose chemotherapy, which was followed by autologous peripheral blood progenitor cell transplantation, and to determine their risk factors. PATIENTS AND METHODS: We retrospectively analyzed the occurrence and the characteristics of infections in 277 consecutive patients who received intensive chemotherapy for non-Hodgkin's lymphoma (n = 207), Hodgkin's disease (n = 27), or multiple myeloma (n = 43) in a single institution. Conditioning regimens included total body irradiation in 47% of the cases. Infections occurring within the 30 days after transplant were defined as early infections, whereas infections after that time in patients who had achieved a neutrophil count greater than 1.0 x 10(9)/L (1,000 per microL) were considered as late infections. RESULTS: Within the first 30 days, 172 patients had unexplained fever (62%); infections were documented in 83 patients (30%), most commonly bacteremia (57 patients). Late infections occurred in 64 (26%) of 244 evaluable patients and consisted mainly of varicella zoster virus infections (n = 36) and pneumonia (n = 16). Administration of total body irradiation [odds ratio (OR) = 2.50; 95% confidence interval (CI) 1.4 to 4.5; P = 0.002) and previous use of fludarabine (OR 2.5; CI 1.2 to 5.2; P = 0.02) and a diagnosis of myeloma (OR 2.6; CI 1.2 to 5.6; P = 0.04) were significantly associated with late infections. CONCLUSIONS: This study confirms that infectious toxicity after peripheral blood progenitor cell transplantation is usually moderate, although bacteremia remains a serious problem. Late infections are encountered in about 25% of patients and are more common in those with myeloma, or those who received total body irradiation or fludarabine.

Adolescent↗
PubMed1999

Characterization of germinal center dendritic cells in follicular lymphoma.

A subset of dendritic cells called germinal center dendritic cells (GCDC) has recently been described inside germinal center from reactive lymphoid organs. We investigated this newly recognized population in follicular lymphoma (FL), which is considered to be the pathologic counterpart of germinal center B cells. Immunohistochemistry analysis with a panel of antibodies demonstrated the presence of a cell population with the peculiar GCDC phenotype in FL biopsies and a similar localization of these cells inside tumoral and reactive follicles. Therefore, we analyzed the relationships between GCDC and the other cell subsets of the tumor follicles. Some of CD4+ and CD8+ T lymphocytes present inside the follicle were found to be in close association with GCDC, suggesting a potential implication of GCDC in their activation. In addition, the distribution of GCDC inside FL and reactive follicles did not appear disrupted, in contrast to follicular dendritic cells, the other follicle dendritic cell type. Finally, we demonstrated that GCDC could be detected from FL lymph node cell suspension by flow cytometry. Taken together, these results indicate that FL development is not associated with a disappearance of GCDC or with a lack of physical interactions between GCDC and T cells inside the follicles. In addition, the fact that GCDC can be observed in FL samples by flow cytometry should allow their purification to further study their putative role in FL development and maintenance.

Adult↗
PubMed1999

Variability of polymerase chain reaction detection of the bcl-2-IgH translocation in an international multicentre study.

BACKGROUND: The capacity of the polymerase chain reaction (PCR) to detect very low numbers of cells bearing a t(14;18) translocation has led to its application in assessment of the results of treatment for follicular lymphoma, and suggestions that therapy might be guided by molecular studies. To test the reliability of PCR a collaborative study was undertaken to compare results from different laboratories in Europe and North America. METHODS: Twenty laboratories with records of publication in molecular diagnostics were sent blood from normal donors with varying numbers of t(14;18)-bearing cells added from a cell line with a translocation in the major breakpoint region (MBR) of the bcl-2 gene. Samples contained 1000, 100, 10, 1 or 0 cells per ml of whole blood and were sent blinded in duplicate. PCR methodology varied widely, with the total number of amplification cycles between 30 and 70, and 13 different primers used for the MBR region. Twelve laboratories used nested PCR and eight single round amplification. RESULTS: The sensitivity of nested and single round PCR was similar at 100 cells/ml but below this the nested method proved significantly more sensitive. The false positive rate was 28%, with 11 samples from 9 laboratories reported as positive when no t(14;18) cells were added. PCR product size and sequence analysis showed that false positives were due to contamination from cell-line DNA rather than background translocations in the donors. There was no significant difference in false positive rates between nested and single round techniques. CONCLUSION: The polymerase chain reaction to detect bcl-2-IgH rearrangements is presently carried out with widely disparate results. Further effort is required to bring forward a standard PCR protocol which can be re-tested in different laboratories to improve accuracy and reproducibility. The application of quantitative techniques such as real-time PCR may resolve many of the problems presently encountered.

Adult↗
PubMed1999

Inactivating mutations and overexpression of BCL10, a caspase recruitment domain-containing gene, in MALT lymphoma with t(1;14)(p22;q32).

Mucosa-associated lymphoid tissue (MALT) lymphomas most frequently involve the gastrointestinal tract and are the most common subset of extranodal non-Hodgkin lymphoma (NHL). Here we describe overexpression of BCL10, a novel apoptotic signalling gene that encodes an amino-terminal caspase recruitment domain (CARD), in MALT lymphomas due to the recurrent t(1;14)(p22;q32). BCL10 cDNAs from t(1;14)-positive MALT tumours contained a variety of mutations, most resulting in truncations either in or carboxy terminal to the CARD. Wild-type BCL10 activated NF-kappaB but induced apoptosis of MCF7 and 293 cells. CARD-truncation mutants were unable to induce cell death or activate NF-kappaB, whereas mutants with C-terminal truncations retained NF-kappaB activation but did not induce apoptosis. Mutant BCL10 overexpression might have a twofold lymphomagenic effect: loss of BCL10 pro-apoptosis may confer a survival advantage to MALT B-cells, and constitutive NF-kappaB activation may provide both anti-apoptotic and proliferative signals mediated via its transcriptional targets.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Toxicities after peripheral blood progenitor cell transplantation for lymphoid malignancies: analysis of 300 cases in a single institution.

Two hundred and seventy-seven consecutive patients with non-Hodgkin's lymphoma (n = 207), Hodgkin's disease (n = 27) and multiple myeloma (n = 43) were intensified from October 1989 until April 1997 and received unmanipulated PBPC transplants. Twenty-three patients received a double intensification, out of a total of 300 PBPC transplantations analyzed. Conditioning regimens consisted of total body irradiation (TBI)-containing regimens (n = 141), BEAM (n = 104), high-dose melphalan (n = 26), ICE (n = 23) or other regimens (n = 6). Eighty-four percent of the patients (119/142) evaluable for long-term hematological reconstitution beyond 180 days achieved normal trilineage blood counts. Abnormal hematological parameters were associated with low numbers of CD34+ cells re-infused and with prior exposure to fludarabine. The 100-day and long-term treatment-related mortality rates were 4% and 4%, respectively. Late complications and treatment-related toxicities were influenced by disease history, use of TBI and exposure to fludarabine. Patients older than 60 years did not have greater toxicities or more frequent treatment-related deaths. This analysis suggests that while leading to a limited morbidity and a low mortality rate, intensive chemotherapy with PBPC transplantation still remains a procedure leading to significant short- and long-term toxicities. Better recognition of the risk factors associated with these complications might allow a further decrease in their incidence.

Adolescent↗
PubMed1999

Translocations involving the short arm of chromosome 17 in chronic B-lymphoid disorders: frequent occurrence of dicentric rearrangements and possible association with adverse outcome.

Unbalanced translocations involving chromosome arm 17p, where the TP53 tumor suppressor gene localizes, are rarely described in chronic lymphocytic leukemia and small lymphocytic lymphoma (CLL/SLL), but recent use of molecular cytogenetic techniques have indicated a significant incidence of TP53 deletions, suggesting the involvement of chromosome 17p in these disorders. By conventional karyotype, we have identified unbalanced translocations involving 17p in 14 out of 123 (11%) CLL/SLL patients with clonal abnormalities. Cases were characterized by resistance to chemotherapy and a poor clinical outcome. The karyotypes presented a high incidence of complex rearrangements and 17p translocations were characterized by various partners. In 10 cases a centric fusion was assessed by fluorescent in situ hybridization (FISH) experiments using specific centromeric probes. The incidence of dicentric translocations in these series is therefore significantly higher than usually described, arising in up to 71% (10 out of 14 cases). In all cases, translocations led to a monosomy 17p and to a TP53 monoallelic deletion. The adverse clinical outcome confirms that structural abnormalities involving chromosome 17p are associated with disease progression in patients with chronic lymphoproliferative disorders.

Antineoplastic Agents↗
PubMed1999

Profiles and prognostic values of LDH isoenzymes in patients with non-Hodgkin's lymphoma.

Serum lactic dehydrogenase (LDH) is an important prognostic factor in patients with non-Hodgkin's lymphoma (NHL). We have examined the LDH isoenzyme content in serum and CSF of patients with NHL, at diagnosis and at relapse. In patients with increased serum LDH at diagnosis, the percentage of isoenzyme 2 was increased in 52% of patients and the absolute value of isoenzyme 3 was increased in 64% of patients. In relapsing patients these values were respectively 69% and 65%. Conversely in patients with increased serum LDH due to myeloid regeneration after chemotherapy, isoenzymes 4 and 5, but not isoenzymes 2 or 3, were increased. High absolute values of isoenzyme 3 were correlated with an altered performance status, advanced tumor stage, and aggressive histology whereas high isoenzyme 2 percentages were correlated with altered performance status only. Among patients with high total serum LDH, a high content of isoenzyme 2 and a high absolute value of isoenzyme 3 were correlated with high serum levels of TNFalpha and TNF receptor p75. Analysis of total LDH and LDH isoenzyme profiles in CSF did not reveal any correlation with meningeal involvement by lymphoma. High isoenzyme 2 percentages and high absolute values of isoenzyme 3 in serum were both significantly associated with a shorter freedom-from-progression and overall survival. Isoenzyme 3 remained a prognostic factor for survival even when considering only patients with high total serum LDH at diagnosis. We conclude that there are some characteristic serum LDH isoenzyme profiles in patients with NHL and that some of these specific alterations may help refine the prognostic value of total serum LDH.

Adolescent↗
PubMed1999

Modulation of costimulatory molecules on follicular lymphoma cells by TNF and CD40.

TNF has recently been implicated in the formation of germinal center cells in lymphoid organs. Follicular lymphoma (FL) is thought to represent the pathological counterpart of germinal center B-cell. High levels of TNF and its soluble receptors were found in the plasma of FL patients whereas the transcripts of these molecules were previously found to be present in FL patients lymph nodes. We therefore studied here the effects of TNF on the expression of costimulatory molecules implicated in the cytotoxic T cell response on purified FL cells. In contrast to results described with B-type chronic lymphocytic leukemia, also characterized by high levels of circulating TNF, none of the tested samples showed a regulation of CD80, CD86, CD27 and CD70 in response to TNF. To confirm that the lack of regulation of these molecules was not due to the FL cells inability to modulate their expression, we therefore analyzed costimulatory molecules expression after CD40 pathway stimulation. After culture with human CD40L-transfected L-cells, an up-regulation of CD80, CD86 and CD70 expression was observed, while TNF addition in this model did not influence these changes. In this context, the CD27 molecule was down-regulated except in a single case, where its expression was increased. Taken together, this data demonstrates that in vitro expression of costimulatory molecules such as CD80, CD86, CD27 and CD70, which are implicated in the anti-tumoral response, can be regulated by CD40 ligand but not by TNF.

Aged↗