G Cartron1, M Ohresser2, G Salles3, P Solal-Céligny4, P Colombat5, H Watier2. 1. EA3853, Immuno-Pharmaco-Génétique des Anticorps Thérapeutiques, Université François Rabelais, Tours; INSERM U847, Biothérapies des cellules souches normales et cancéreuses and Service d'Hématologie et Biothérapies, CHU Lapeyronie, Montpellier. Electronic address: guillaume.cartron@med.univ-tours.fr. 2. EA3853, Immuno-Pharmaco-Génétique des Anticorps Thérapeutiques, Université François Rabelais, Tours. 3. Service d'Hématologie, Hospices Civiles de Lyon, Université Claude Bernard, Lyon. 4. Department of Hématologie, Centre Jean-Bernard, Le Mans. 5. Service d'Hématologie et Thérapie Cellulaire, CHU Bretonneau, Tours, France.
Abstract
BACKGROUND: Neutrophils could play an important role in in vivo rituximab anti-lymphoma activity. FcgammaRIIIb is expressed only by neutrophils and FcgammaRIIIb-neutrophil antigen (NA)1/NA2 polymorphism influenced phagocytosis of immunoglobulin G1-opsonized particles. We formulated the hypothesis that if neutrophils are critical cells for in vivo rituximab activity, FcgammaRIIIb-NA1/NA2 polymorphism could influence the response to rituximab. PATIENTS AND METHODS: FCGR3B-NA1/NA2 genotypes were determined in 46 patients having received rituximab for a previously untreated, follicular, non-Hodgkin's lymphoma. The clinical response and the disappearance of the BCL2-JH gene rearrangement in both peripheral blood and bone marrow were evaluated at 2 months (M2) and each year during 7 years. RESULTS: They were 13% homozygous for FCGR3B-NA1, 61% homozygous for FCGR3B-NA1/NA2 and 26% heterozygous. The objective response rates at M2 were 67% in homozygous FCGR3B-NA1 patients compared with 75% in homozygous FCGR3B-NA2 and 75% in heterozygous patients (not significant). We found no difference for progression-free and overall survival by FCGR3B-NA1/NA2 genotypes. CONCLUSION: These results indicate no association between FCGR3B-NA1/NA2 polymorphism and response to rituximab indicating no significant role of phagocytosis mediated by neutrophils in in vivo mechanism of rituximab activity.
BACKGROUND: Neutrophils could play an important role in in vivo rituximab anti-lymphoma activity. FcgammaRIIIb is expressed only by neutrophils and FcgammaRIIIb-neutrophil antigen (NA)1/NA2 polymorphism influenced phagocytosis of immunoglobulin G1-opsonized particles. We formulated the hypothesis that if neutrophils are critical cells for in vivo rituximab activity, FcgammaRIIIb-NA1/NA2 polymorphism could influence the response to rituximab. PATIENTS AND METHODS: FCGR3B-NA1/NA2 genotypes were determined in 46 patients having received rituximab for a previously untreated, follicular, non-Hodgkin's lymphoma. The clinical response and the disappearance of the BCL2-JH gene rearrangement in both peripheral blood and bone marrow were evaluated at 2 months (M2) and each year during 7 years. RESULTS: They were 13% homozygous for FCGR3B-NA1, 61% homozygous for FCGR3B-NA1/NA2 and 26% heterozygous. The objective response rates at M2 were 67% in homozygous FCGR3B-NA1 patients compared with 75% in homozygous FCGR3B-NA2 and 75% in heterozygous patients (not significant). We found no difference for progression-free and overall survival by FCGR3B-NA1/NA2 genotypes. CONCLUSION: These results indicate no association between FCGR3B-NA1/NA2 polymorphism and response to rituximab indicating no significant role of phagocytosis mediated by neutrophils in in vivo mechanism of rituximab activity.
Authors: Sean H Lim; Stephen A Beers; Ruth R French; Peter W M Johnson; Martin J Glennie; Mark S Cragg Journal: Haematologica Date: 2009-09-22 Impact factor: 9.941