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V Salaün

Publications and source records attributed to V Salaün.

8 recordsLinked to original sources
PubMed2001

Upstream mediators of the Fas apoptotic transduction pathway are defective in B-chronic lymphocytic leukemia.

Data concerning the presence and the functionality of Fas receptor in malignant B-cells are controversial. We have analyzed Fas molecules on B-cells from patients with B-chronic lymphocytic leukemia (B-CLL) cells. We observed a large variability, both of percentage of Fas-positive cells and of intensity of Fas level. Fas triggering was inefficient in inducing apoptosis whatever the number of Fas-positive B-cells, the amount of Fas receptors. B-cells were also resistant to etoposide treatment, but able to undergo apoptosis after dexamethasone treatment. We suggest that the Fas apoptotic pathway is altered in B-CLL patients at the initial step(s) of apoptotic machinery.

Adaptor Proteins, Signal Transducing↗
PubMed2001

No BCL-2 protein over expression but BCL-2/IgH rearrangements in B cells of patients with persistent polyclonal B-cell lymphocytosis.

INTRODUCTION: Persistent polyclonal B-cell lymphocytosis is a rare hematological disorder, characterized by a chronic, stable and absolute polyclonal lymphocytosis, the presence of binucleated lymphocytes, a polyclonal increase in serum IgM immunoglobulin and clonal cytogenetic abnormalities involving chromosome 3. For explaining the expansion of B-lymphocytes pool in PPBL, an association with cigarette smoking and/or chronic Epstein-Barr virus infection have been suggested but both hypotheses have been ruled out. MATERIALS AND METHODS: We studied the presence of BCL-2/IgH rearrangements in a series of eight PPBL patients (seven females and one male) by a nested polymerase chain reaction (PCR), targeting the Major Breakpoint Region in BCL-2 locus and we explored the BCL-2 protein expression by Western blot. RESULTS: We demonstrated: (a) the constant presence of BCL-2/IgH rearrangements in eight out of eight DNA samples, (b) multiple rearrangements in three out of eight cases and, (c) normal BCL-2 protein expression, as compared to BCL-2 level in B-lymphocytes from healthy population. CONCLUSION: Despite the presence of BCL-2/IgH rearrangements, the accumulation of B lymphocytes in PPBL is not related to an overexpression of BCL-2 protein.

Adult↗
PubMed1999

Transcriptional and post-transcriptional mechanisms induce cyclin-D1 over-expression in B-chronic lymphoproliferative disorders.

Cyclin D1 participates in cell-cycle control, in the progression through the G(1) phase and in the transition from the G(1) to the S phase. The CCND1 locus, located in 11q13, is amplified and cyclin-D1 protein is over-expressed in a wide range of human solid tumors. In some B-lymphoid malignancies, the t(11;14)(q13;q32) translocation joins the Ig heavy-chain locus to the CCND1 locus and leads to cyclin-D1 over-expression. In this study, a series of 127 patients presenting a B-chronic lymphoproliferative disorder (B-CLPD) was analyzed using a competitive RT-PCR designed to detect cyclin-D1-mRNA over-expression. Cyclin-D1 mRNA was expressed in patients with mantle-cell lymphoma (MCL; 10/10), hairy-cell leukemia (HCL; 3/5), B-chronic lymphoid leukemia (B-CLL; 4/111) and B large-cell lymphoma (BLCL; 1/1). Densitometric analysis of RT-PCR products and Western-blot autoradiograms, in addition to cytogenetic data, indicated that activation of the cyclin-D1 gene occurred independently of the t(11;14)(q13;q32) translocation in patients with HCL. Indeed, a normal-sized protein of 36 kDa exhibiting a level incompatible with gene activation by a translocation mechanism was detected in lymphoid cells with a normal karyotype. Moreover, we found a discrepancy between cyclin-D1 mRNA and protein levels in MCL and B-CLL, which suggested that some regulatory mechanisms acting at a post-transcriptional level persist in tumor cells.

Adult↗
PubMed1998

[Castleman's disease of the abdomen].

Plasmocytic variants of Castleman's disease are uncommon. We report a new case of abdominal location with a rapidly fatal outcome. Another particularity of that case was the negativity of Kaposi's sarcoma associated herpesvirus, a virus recently implicated in human immunodeficiency virus associated Castleman's disease.

Aged↗
PubMed1997

Hematopoietic changes induced by a single injection of anti-CD3 monoclonal antibody into normal mice.

The present study evaluates hematopoietic modifications consecutive to in vivo treatment of mice with anti-CD3 monoclonal antibodies (mAb). The hamster mAb 145-2C11, administered in a single i.v. injection of 10 micrograms, induced the release of both interleukin 3 (IL-3) and GM-CSF into the circulation. IL-3 could be detected in the serum within 1 h, attained maximal levels after 4 h and had disappeared after 24 h. Three days later, treated mice exhibited a two- to threefold rise in blood neutrophil levels and increased spleen cell counts. Concomitantly, the incidence of nucleated erythroid cells in these spleens increased around 10-fold, relative to controls having received hamster Ig. At the same time point, clonogenic progenitor frequencies were 10-fold higher in spleens from treated mice than in those from control mice. Furthermore, the responsiveness of these splenocytes to IL-3, in terms of histamine synthesis, was enhanced. In contrast, bone marrow cell populations were only slightly affected by anti-CD3 injection. All hematopoietic changes required multivalent crosslinking of the mAb for induction, since F(ab')2 fragments lacked this activity. A return to normal occurred 7-10 days after treatment. Two i.v. injections of recombinant murine IL-3 together with recombinant murine GM-CSF on a single day had a less pronounced effect on progenitor cell frequencies in the spleen than treatment with anti-CD3. This difference is probably due to the amplification of growth factor-induced hematopoiesis by the interaction with other cytokines generated in response to anti-CD3.

Animals↗
PubMed1994

Biological markers and ovarian carcinomas: galactosyltransferase, CA 125, isoenzymes of amylase and alkaline phosphatase.

We present a comparative study of several biological markers (galactosyltransferase, CA 125, isoenzymes of amylase and alkaline phosphatase) with a view to ovarian carcinoma follow-up. Serum samples were obtained from a population of 75 patients under clinical observation. After a minimum 18-months period, we assessed the prognostic value of the markers. No marker permits the detection of discrete, evolving carcinomas. CA 125 is the marker that gives the best results, particularly in terms of sensitivity. Galactosyltransferase has a lower sensitivity except in the case of endometrioid carcinomas. Simultaneous analysis with CA 125 and galactosyltransferase results in no decisive improvement, other than greater precision in unfavourable prognoses. Isoenzymes of amylase and alkaline phosphatase are of no interest in the follow-up of such carcinomas.

Alkaline Phosphatase↗