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M C Favrot

Publications and source records attributed to M C Favrot.

At least 37 records · Page 2Linked to original sources
PubMed1996

Comparison of the diagnostic and prognostic value of biological markers in neuroblastoma. Proposal for a common methodology of analysis. SENSE group.

BACKGROUND: The prognosis of pediatric neuroblastoma depends both on clinical presentation and on certain cellular and molecular characteristics. Screening programs have been initiated in infants of less than one year of age, based on the hypothesis that neuroblastoma progresses from early to late clinical stages through a classical multistep process linked to an accumulation of molecular abnormalities. However, recent analyses suggest that most cases discovered by screening are low stage tumors considered as dysembryogenetic residues devoid from major abnormalities and that high-grade tumors with molecular abnormalities are unrelated diseases. AIM OF THE REVIEW: To confirm one or the other hypothesis, and eventually identify biological factors possibly responsible for the initiation and progression of the disease, it is of utmost importance that all investigators agree on biological criteria for analysis when neuroblastoma tissue is available in screened and unscreened populations. This paper reviews the biological tools available for prognosis in neuroblastoma, the priority for analysis of biological markers according to both methodological reliability and feasibility, and the conditions of tissue storage for further analysis of these biological markers. CONCLUSION: The standardized biological evaluation of neuroblastoma will allow to collect sufficient data for multivariate analysis; such analysis is now fundamental if one wants to clearly define the respective impacts of biological abnormalities on neuroblastoma progression.

Biomarkers, Tumor↗
PubMed1996

Clinical relevance of CD44 cell-surface expression and N-myc gene amplification in a multicentric analysis of 121 pediatric neuroblastomas.

PURPOSE: In contrast to other human tumors, a repression of the cell-surface glycoprotein CD44 on neuroblastoma is a marker of aggressiveness that usually correlates to N-myc amplification. We thus compared the prognostic value of both markers in the initial staging of 121 children treated for neuroblastoma in collaborative institutions. METHODS: Frozen samples were analyzed by a rapid and well-standardized technique of immunostaining with monoclonal antibodies (MoAbs) against epitopes in the CD44 constant region. RESULTS: In this retrospective series, CD44 was expressed on 102 specimens and strongly correlated with favorable tumor stages and histology, younger age, and normal N-myc copy numbers. In univariate analysis, CD44 expression and normal N-myc were the most powerful markers of favorable clinical outcome (P < 10(-6) and chi 2 = 65.40 and P < 10(-6) and chi 2 = 42.56, respectively), but analysis of CD44 affords significant prognostic discrimination in subgroups of patients with or without N-myc-amplified tumors. In the subgroup of stage IV neuroblastomas, CD44 was the only significant prognostic marker (P < .02, chi 2 = 5.76), whereas N-myc status was not discriminant. In multivariate analysis of five factors, ie, N-myc amplification, CD44 expression, age, tumor stage, and histology, the only independent prognostic factors of event-free survival were CD44 expression and tumor stage. CONCLUSION: The analysis of CD44 cell-surface expression must be recommended as an additional biologic marker in the initial staging of the disease.

Antibodies, Monoclonal↗
PubMed1995

Somatic mutations of von Hippel-Lindau (VHL) tumor-suppressor gene in European kidney cancers.

Somatic mutations of von Hippel Lindau (VHL) tumor-suppressor gene have been identified in kidney cancers from North America and Japan. We studied VHL gene mutation in 31 kidney tumors from France. Of these tumors, 45% (14/31) displayed mutations, 60% of which occurred at A:T base pairs. The frequency and the spectrum of mutations identified in kidney tumors from Europe were similar to those reported for tumors from other geographical locations.

Adult↗
PubMed1995

Sensitive detection of numerical and structural aberrations of chromosome 1 in neuroblastoma by interphase fluorescence in situ hybridization. Comparison with restriction fragment length polymorphism and conventional cytogenetic analyses.

Chromosome I abnormalities are indicators of prognosis in neuroblastoma (NB) but are not yet routinely exploited because conventional methods are technically demanding. We evaluated the pertinence of interphase cytogenetics fluorescence in situ hybridization (FISH) for the analysis of chromosome I in NB, compared with conventional methods. Deletion of Ip was detected in 8 of 9 cell lines analyzed by both FISH and restriction fragment length polymorphism (RFLP), but was evidenced in only 2 cases by conventional cytogenetics, painting analysis being required to reveal the other cases. The chromosome I number evaluated by FISH reflected the total chromosome modal number obtained by cytogenetics. Twenty-eight specimens obtained from ultrasound-guided punctures, surgical biopsies of the primary tumor and bone-marrow aspirates were studied by FISH on frozen cytocentrifuged smears; 12 had a chromosome I trisomy and 16 a disomy. Requirements for a reliable control analysis of Ip deletion by RFLP were met in only 23 cases. The retention of 2 alleles was observed in 15 cases and Ip deletion in 7, by both techniques. In one case, an interstitial deletion of Ip was evidenced only by RFLP, and one of 5 cases analyzed only by FISH had a Ip deletion. Although FISH might be improved by using additional probes, it presents major advantages for routine exploitation. Determining Ip deletion in individual cells makes it possible to analyze small and heterogeneous tumoral specimens; the technique requires only a few hours and can easily be standardized in non-specialized laboratories. The number of chromosome I homologues per cell might serve as a rapid screening for ploidy.

Biopsy↗
PubMed1995

Evaluation of CD44 prognostic value in neuroblastoma: comparison with the other prognostic factors.

CD44 gene products are potential markers of aggressiveness in different tumour models, a result which prompted us to study clinical neuroblastoma (NB) specimens. CD44 expression was determined by immunostaining of 52 tumour samples from newly diagnosed NB with a monoclonal antibody (J173) directed against an epitope common to all CD44 isoforms. CD44 immunoreactivity was detected in 37 of the tumours (71%). CD44 was expressed in all 22 NBs with favourable prognoses (stages 1, 2 or 4S), but only 50% (15/30) of advanced NB (stages 3 and 4) (P < 10(-4)), suggesting that the absence, rather than the overexpression, of CD44 is a signal of tumour aggressiveness. The cumulative progression-free survival was significantly longer in patients with CD44 positive tumours compared with patients with CD44 negative tumours (P < 10(-5)). More importantly, progression-free survival was also significantly higher in CD44 positive patients within the high-risk group (P < 0.01). In univariate analysis, we tested the prognostic value of tumour expression of CD44 in comparison with tumour stage, age, tumour histology, and presence or absence of amplification of the MYCN protooncogene. All five measures had significant prognostic value. The expression of CD44 and the absence of MYCN amplification were the most powerful predictors of a favourable outcome. In a multivariate analysis of these measures, CD44 expression and tumour stage were the only independent prognostic factors for the prediction of patient survival. NB is the first clinical model described in which tumour aggressiveness correlates with repression rather than stimulation of CD44 expression. We recommend the use of CD44 as an additional biological marker in the initial staging of NB.

Adolescent↗
PubMed1995

[CD44 expression: a new prognostic factor in neuroblastoma].

CD44 gene products are potential markers of aggressiveness in different tumor models, a result which prompted us to study clinical neuroblastoma (NB) specimens. CD44 expression was determined by immunostaining of 52 NB with a monoclonal antibody (J173) directed against an epitope common to all CD44 isoforms. All tumors were from patients (pts) with newly diagnosed NB treated with standardized protocols. They were classified according to international criteria [11]. CD44 immunoreactivity was detected in 37 tumors (71%). CD44 was expressed in 100% of favorable NB stages (1, 2 or 4S), but only 50% of advanced NB (stages 3 and 4) (p = 0.0001), suggesting that the absence rather that the overexpression of CD44 is a signal of tumor aggressiveness. The cumulative event-free survival was significantly longer in pts with CD44-positive tumors as compared to pts with CD44-negative tumors (p < 10(-5)). More importantly, progression-free survival was also significantly higher in CD44-positive pts within the high-risk group (p < 0.01). In univariate analyses, we tested the prognostic value of tumor expression of CD44 in comparison with tumor stage, age, tumor histology and presence or absence of N-myc proto-oncogene amplification. All five measures had significant prognostic value. The expression of CD44 and the absence of N-myc amplification were the most powerful predictors of a favorable clinical outcome. In a multivariate analysis of these measures, CD44 expression and tumor stage were the only independent prognostic factors for the prediction of patient survival. NB is the first clinical model described in which tumor aggressiveness correlates with a repression rather than a stimulation of CD44 expression. We recommend the use of CD44 as an additional biological marker in the initial staging of neuroblastoma.

Adolescent↗
PubMed1993

[Neuroblastoma. Current clinical and therapeutic aspects. Contributions of modern biology].

Neuroblastoma is a malignant tumour of the sympathetic tissue observed in children, generally before 6 years and before 1 year in one-third of the cases. In most cases the primary tumour lies in the retroperitoneal region, and in particular in the adrenal gland. Metastases affect the bones and bone-marrow after the age of 1 year and the liver in infants. Children whose metastases are present at the time of diagnosis are the most numerous. The therapeutic problems posed by non-metastatic forms are almost exclusively due to the difficulties encountered in complete excision of the tumour. For this reason, tumour reduction by preoperative chemotherapy plays a large role in the therapeutic approach. The prognosis of metastatic forms is totally different in infants and in older children: in infants, hepatic metastases without bone lesions have a favourable prognosis as a rule and sometimes regress without treatment. In older children, the usual osteomedullary damage still has a very sombre prognosis despite the recent therapeutic advances due to high-dose chemotherapy with bone-marrow transplantation. Cytogenetic studies and molecular biology have improved our understanding of these differences in the outcome of the disease. Amplification of Nmy cellular oncogene, ploidy and chromosome 1 short-arm deletion are essential prognostic factors in this particular tumour.

Child, Preschool↗
PubMed1993

Serum interleukin-10 in non-Hodgkin's lymphoma: a prognostic factor.

Serum interleukin-10 (IL-10) was measured retrospectively in 153 patients with a fully documented history of non-Hodgkin's lymphoma (NHL) using an enzyme-linked immunosorbent assay (ELISA) detecting both human IL-10 and the Epstein-Barr virus (EBV) molecule BCRF1/viral IL-10. IL-10 was detectable in 47 (46%) of the 101 patients with active NHL, 3 of 52 (6%) patients in first partial or complete response, and none of the 60 healthy blood donors. Serum IL-10 was detectable with a similar frequency in all subtypes of NHL and in all clinical stages, as well as in EBV-seropositive and EBV-negative patients. In patients with intermediate or high-grade NHL, the presence of detectable serum IL-10 at diagnosis was correlated to a significantly shorter overall (P = .025) and progression-free (P = .030) survival. Patients with stage IV disease and detectable serum IL-10 had a particularly poor prognosis (4 years of survival: 0%). Multivariate analysis showed that IL-10 was an independent prognosis factor. These results indicate that IL-10 is detectable in a subgroup of patients with active NHL and correlates to a poor survival in patients with intermediate or high-grade NHL.

Adolescent↗
PubMed1992

Tumor necrosis factor as an autocrine growth factor for neuroblastoma.

Recombinant tumor necrosis factor (TNF) stimulates the proliferation of two neuroblastoma cell lines, SKNFI and SKNBE, in both serum-free medium and fetal calf serum-supplemented medium but has no effect in medium without insulin. This effect is very similar with TNF doses ranging from 5 to 500 ng/ml but depends on the duration of treatment; when cells are treated for 168 h with TNF, the maximal index of proliferation is observed between 120 and 144 h of treatment. The two neuroblastoma cell lines express type A and type B TNF receptors and contain TNF protein; however, TNF is undetectable in culture supernatants. Treatment of the two neuroblastoma cell lines with a rabbit polyclonal antibody to TNF for 96 h fully inhibits [3H]thymidine incorporation; less than 5% viable cells are left in the samples after treatment. A combination of two monoclonal antibodies against type A and type B TNF receptors also inhibits over 85% of the [3H]thymidine incorporation by the two cell lines after 96 h of treatment; the use of a single antibody has a partial effect, suggesting that both receptors are functional on the neuroblastoma cell lines. Taken together, these results show that TNF is an autocrine growth factor for the two neuroblastoma cell lines SKNFI and SKNBE. The results described above have been confirmed on two other neuroblastoma cell lines, IRM32 and CLB-PE.

Cell Division↗
PubMed1992

Retroviral gene therapy and its application in oncohematology.

A symposium entitled "Foetal and Neonatal Cell Transplantation and Retroviral Gene Therapy" recently organized under the aegis of the Mérieux Foundation in Annecy, France, brought together 100 scientists and clinicians from European countries and the United States. The last day of the meeting focused on retroviral gene therapy in oncohematology. The speakers provided the basis for therapeutic applications of gene transfer and showed practical directions to be followed in the near future. Although it may be mainly restricted to in vitro manipulation of human cells at start, gene therapy is already applicable to the treatment of genetic disorders, cancer, and viral infections. The reality of gene therapy was well illustrated by the nature of the questions raised by clinicians and scientists during the meeting.

Animals↗
PubMed1991

Expression of integrin receptors on 45 clinical neuroblastoma specimens.

Immunohistological expression of integrins has been analyzed on 45 neuroblastoma specimens representative of the different clinical and histological forms of the tumor. None of the specimens expressed the alpha 5 chain of the integrins. The beta 1 chain was expressed on all specimens, the alpha 1 chain on 44 specimens and the alpha 3 chain on 42; the 4 specimens which lacked alpha 1 or alpha 3 were stage-4 neuroblastomas. The alpha 2 chain was expressed on 18 specimens, and the alpha 6 chain on 17; 15 reacted with both. Their reactivity was related to the maturation of the tumor rather than the stage of the disease: they were expressed on low-grade, well-differentiated specimens; stage 3-4 neuroblastoma specimens analyzed at diagnosis were negative, but usually expressed both chains when analyzed after in vivo differentiation by chemotherapy. alpha v reacted with 18 specimens and beta 3 with 12, without strict relation with the stage of the disease and/or its degree of differentiation; 9 well-differentiated specimens expressed the beta 4 chain; only 4 well-differentiated specimens expressed the alpha 4 chain. The 4 specimens which lacked alpha 1-beta 1 or alpha 3-beta 1 expression had n-myc amplification, whereas those which expressed either alpha 4, beta 4, beta 3 or alpha v had no amplification. Furthermore, the expression of the 3 heterodimers alpha 4-beta 1, alpha v-beta 3 and alpha 6-beta 4 was essentially observed on primary tumors which developed in the mediastinum. The expression of alpha 2-beta 1 and alpha 6-beta 1 was observed on both n-myc-positive and -negative specimens. beta 1 and alpha 3 were diffusely expressed on all counterparts of these tumors, from undifferentiated neuroblasts to ganglion and Schwann cells. The alpha 1 chain reacted with undifferentiated and intermediate neuroblasts as well as with Schwann cells, but ganglion cells were negative. alpha 2 and alpha 6 chains were negative on undifferentiated neuroblasts, variably expressed on intermediate neuroblasts, and restricted to Schwann cells in ganglioneuroma. The expression of alpha 4 and beta 4 was restricted to Schwann cells. alpha v and beta 3 occasionally reacted with undifferentiated and intermediate neuroblasts; alpha v was strongly positive on Schwann cells but negative on ganglion cells, whereas beta 3 was positive on both neuronal and non-neuronal populations.

Ganglioneuroma↗
PubMed1991

Expression of leucocyte adhesion molecules on 66 clinical neuroblastoma specimens.

LFA-3, ICAM-1, HLA.ABC and HLA.DR expression was analyzed on 66 neuroblastoma specimens. HLA.ABC was expressed on 26 specimens, HLA.DR on 2, LFA-3 on 20 and ICAM-1 on 10. HLA.ABC and LFA-3 were positive on ganglioneuroblastoma or ganglioneuroma, but they were negative on neuroblastoma, independently of the clinical staging; HLA.ABC and LFA-3 were induced in vivo by chemotherapy in parallel with tumoral cell differentiation, in both the primary and the metastases. The expression of ICAM-1 was restricted to 5 of the 10 low-grade stage-1 or stage-2 specimens, 1 stage-3 specimen, and the primary tumors of 2 patients with stage-4 disease, analyzed hence at diagnosis and after chemotherapy (4 specimens); metastatic cells obtained in 1 of these patients were negative. HLA.ABC and LFA-3 expressed on both mycN-negative and -positive specimens, whereas ICAM-1 was restricted to MYCN-negative specimens. LFA-3 diffusely stained partially differentiated neuroblasts, Schwann cells and ganglion cells. The expression of HLA.ABC on differentiated neuroblasts varied from one sample to another and within the same tumor; Schwann cells were strongly positive, but ganglion cells were negative. In positive samples, ICAM-1 was expressed on differentiated neuroblasts and Schwann cells, but negative on ganglion cells; however, most of the differentiated tumors were ICAM-1-negative, suggesting ICAM-1 induction by unknown local signal. The 4 markers were negative on undifferentiated neuroblasts. The distribution of these 4 markers on clinical specimens was in agreement with their reactivity on fetal tissues, as well as with results obtained on neuroblastoma cell lines before and after in vitro treatment with IFN-gamma.

Alkaline Phosphatase↗
PubMed1991

Renal effects of continuous infusion of recombinant interleukin-2 in children.

Recombinant interleukin-2 (rIL-2) is a new promising treatment for cancer, but is associated with severe renal toxicity. This study is the first to analyse the renal effects of rIL-2 in children. Twenty-one cycles of continuous rIL-2 infusion were studied in 15 patients; mean age was 6.9 years and average weight 18.9 kg. Interstitial fluid retention and oliguria (baseline, 1.7 ml/kg per hour; nadir, 0.5 mg/kg per hour) were associated with hypotension (baseline, 101/56 mm Hg; nadir, 85/43 mm Hg) and decreased intravascular volume (plasma renin activity increased x 10). Weight gain (+7.9%) was observed in 13 cycles whereas weight loss (-6.3%) was shown in 8 cycles because of digestive and cutaneous losses, mainly in the youngest patients. This prerenal azotaemia was characterized by a decrease in creatinine clearance (from 101 to 36 ml/min per 1.73 m2) and a low fractional excretion of sodium (FENa) (from 0.70% to 0.09%). Hypotension and hypovolaemia needed vascular filling (n = 12), dopamine (n = 7) and interruption of rIL-2 (n = 2). Most abnormalities occurred as early as day 2 of therapy and were always reversible after a short period with sodium leakage (diuresis = 2.2 ml/kg per hour, FENa = 2.01%). Hypophosphataemia was associated with low urinary excretion of phosphorus, suggesting an increased uptake of inorganic phosphorus by rapidly proliferating lymphoid cells.

Adolescent↗
PubMed1991

Management of pediatric non-Hodgkin's lymphoma.

Over the past 15 years, significant progress has been made in the understanding of the molecular mechanism involved in malignant transformation of lymphocytes as well as in the management and treatment of non-Hodgkin's lymphoma (NHL) in childhood. Cyto-histological classifications and immunophenotyping of different types of NHL have contributed to the characterisation of three major subtypes of NHL in children i.e. Burkitt's lymphoma (BL), lymphoblastic lymphoma (LL) and large cell lymphoma (LCL). Precise staging of the disease at diagnosis is necessary before the onset of the treatment and should be performed as quickly as possible. Presence of bone marrow and central nervous system (CNS) involvement are major prognosis criteria. In most cases, surgery has no therapeutic role and is required only for diagnostic procedures. Similarly, several studies have demonstrated that irradiation of various sites including the CNS does not improve survival. Thus, NHL patients are usually treated with chemotherapy alone. BL and LL have distinct clinical presentations and require completely different chemotherapy protocols. After comparable induction phases with intensive chemotherapy regimens, the former is usually treated with a short consolidation phase while the latter receives a long lasting consolidation consisting of intermittent chemotherapy for at least one year. The prognosis of stage I-II, and III-IV bone marrow negative NHL of children is excellent with respectively 95% and 75% long term survival. However, patients with concomittent CNS and bone marrow involvement in both histological subtypes have a considerably worse prognosis with only 30% long term survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Correlation between clinical response to interleukin 2 therapy and sustained production of tumor necrosis factor.

Twenty-five previously untreated patients with metastatic renal cell carcinoma were treated with 5-day cycles of continuous infusion of interleukin 2 (IL2) and lymphokine-activated killer cell reinfusion. Five achieved a partial response. Three patients were found to have detectable tumor necrosis factor (TNF) in serum before initiation of therapy. On the fifth day of therapy, 24 patients had circulating TNF with immunoradiometric assay whereas 13 had detectable biological activity. Two days after the end of IL2 therapy, TNF concentration (immunoradiometric assay) decreased in most cases but was still detectable in 17 patients. Thirteen patients had still circulating TNF bioactivity. Although there was no significant difference between TNF levels observed on the fifth day of therapy in the responder and nonresponder groups, 48 h after the end of IL2 infusion, both the TNF concentration and the biological activity were significantly higher in the group of responder patients. This result suggests that the clinical response to IL2 therapy in patients with metastatic renal cell carcinoma is correlated to a sustained production of TNF after the end of IL2 infusion.

Animals↗