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S Marcé

Publications and source records attributed to S Marcé.

6 recordsLinked to original sources
PubMed2005

Equilibrative nucleoside transporter-2 (hENT2) protein expression correlates with ex vivo sensitivity to fludarabine in chronic lymphocytic leukemia (CLL) cells.

Fludarabine is considered the treatment of choice for most patients with chronic lymphocytic leukemia (CLL). We have analyzed the role of plasma membrane transporters in nucleoside-derived drug bioavailability and action in CLL cells. Among the known plasma membrane transporters, we have previously observed a significant correlation between fludarabine uptake via ENT carriers and ex vivo sensitivity of CLL cells to fludarabine, although mRNA amounts of the equilibrative nucleoside transporters hENT1 and hENT2 do not show any predictive response to treatment. In this study, using polyclonal monospecific antibodies we have observed a significant correlation between the expression of hENT2 by Western blot and fludarabine uptake via hENT carriers and also with ex vivo sensitivity of CLL cells to fludarabine. These results suggest that the equilibrative nucleoside transporter hENT2 plays a role in fludarabine responsiveness in CLL patients.

Antineoplastic Agents↗
PubMed2001

Complement-mediated cell death induced by rituximab in B-cell lymphoproliferative disorders is mediated in vitro by a caspase-independent mechanism involving the generation of reactive oxygen species.

Mechanisms involving the in vitro effect of rituximab in cells from 55 patients with B-cell lymphoproliferative disorders were investigated. No cytotoxic effect was observed when cells were incubated with rituximab alone, but in the presence of human AB serum rituximab induced complement-dependent cell death (R-CDC). A cytotoxic effect was observed in cells from 9 of 33 patients with B-cell chronic lymphocytic leukemia, 16 of 16 patients with mantle-cell lymphoma, 4 of 4 patients with follicular lymphoma, and 2 of 2 patients with hairy-cell leukemia. R-CDC was observed in cells from patients expressing more than 50 x 10(3) CD20 molecules per cell, and directly correlated with the number of CD20 molecules per cell. Preincubation with anti-CD59 increased the cytotoxic effect of rituximab and sensitized cells from nonsensitive cases. Neither cleavage of poly-ADP ribose polymerase (PARP) nor activation of caspase-3 was observed in R-CDC. In addition, no cells with a hypodiploid DNA content were detected and R-CDC was not prevented by a broad-spectrum caspase inhibitor, suggesting a caspase-independent mechanism. Incubation with rituximab in the presence of AB serum induced a rapid and intense production of reactive oxygen species (ROS). R-CDC was blocked by the incubation of cells with N-acetyl-L-cysteine (NAC) or Tiron, 2 ROS scavengers, indicating that the cytotoxic effect was due to the generation of superoxide (O) radicals. In conclusion, the results of the present study suggest that CD20, CD59, and complement have a role in the in vitro cytotoxic effect of rituximab, which is mediated by a caspase-independent process that involves ROS generation.

Adult↗
PubMed1995

Remitting seronegative symmetrical synovitis with pitting oedema: disease or syndrome?

OBJECTIVE: To evaluate the outcome of patients with remitting seronegative symmetrical synovitis with pitting oedema (RS3PE). METHODS: In a retrospective chart review study, we identified all the patients presenting with polyarthritis and pitting oedema in the past 20 years. We tried to recall the 24 patients with characteristics of RS3PE according to McCarty et al. Two patients had died and four could not be traced. Five could not be seen after the initial period of follow up; relevant data were obtained from their practitioner. For the remaining 13 patients, clinical, radiological, and biological evaluation was performed in our department, with the last assessment in 1993. RESULTS: The follow up period was from one to 18 years (mean 4.6 (SD 4.5) years). Eleven patients developed one or several recurrences of articular manifestations consisting of mild oligoarthritis (n = 8), definite spondyloarthropathy (n = 2), and rheumatoid arthritis (n = 1). The delay of the first recurrence was 18 months to 12 years after the first attack. Thirteen patients had no recurrence, but three of them developed remarkable features: rheumatoid factor, antinuclear antibodies (1/2000), Sjögren's syndrome. HLA B typing was performed in nine patients and revealed B7 (n = 2), B27 (n = 2) and B22 (n = 2). Isolated HLA B27 typing was performed in two other patients and was positive in one. CONCLUSION: The long term outcome of RS3PE can lead to different rheumatic diseases. RS3PE appears to be a syndrome related to the elderly onset of the rheumatic diseases, including spondyloarthropathy and rheumatoid arthritis, rather than a specific entity.

Aged↗