TISSUE MICROARRAY TECHNOLOGY IN THE STUDY OF CELLULAR ANTIGEN EXPRESSION

MAGALHÃES BARROS MH; GUIRETTI D; CHABAY P; PRECIADO MV; DE MATTEO E; ZALCBERG I; HASSAN R

Colonia, Alemania

Simposio; 7th International Symposium on Hodgkin Lymphoma; 2007

European Journal of Hematology

The tissue microarray technology (TMA) allows the simultaneous study of many tissues and it is increasingly applied in cancer research. Hodgkin lymphoma (HL) is characterized by a low number of neoplastic cells, raising the question if TMA methodology can warrant a sufficient tumor representation for pathology studies. The objective of this study was to validate TMA for studies of cellular antigen expression and Epstein-Barr virus (EBV) association in HL. A TMA was constructed using a tissue arrayer (Beecher Instruments) including 56 pediatric HL diagnostic tumors, with 2 representative cores (1 mm diameter) of each sample. The phenotype was evaluated by CD30 and CD15 immunostaining. EBV association was determined by EBER-ISH and expression of EBV latent membrane protein LMP1 and LMP2A by immunohistochemistry (IHC). CD30, LMP1 and EBER-ISH detection was also performed in conventional slides, showing expression in 89%, 48% and 37% of the cases, respectively. Concordance between conventional and TMA detection was 100%. Analysis of LMP2A was performed in 51 cases; 12 cases showed membrane or para-nuclear (dot) immunostaining. All LMP2A+ cases showed also LMP1 expression, while 10 were LMP2Anegative/ LMP1+. Core duplication allowed to improve the number of available cases for CD30 (from 51 to 55 cases, p<0.001), LMP1 (43 to 54 cases, p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.dot) immunostaining. All LMP2A+ cases showed also LMP1 expression, while 10 were LMP2Anegative/ LMP1+. Core duplication allowed to improve the number of available cases for CD30 (from 51 to 55 cases, p<0.001), LMP1 (43 to 54 cases, p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.+ cases showed also LMP1 expression, while 10 were LMP2Anegative/ LMP1+. Core duplication allowed to improve the number of available cases for CD30 (from 51 to 55 cases, p<0.001), LMP1 (43 to 54 cases, p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.+. Core duplication allowed to improve the number of available cases for CD30 (from 51 to 55 cases, p<0.001), LMP1 (43 to 54 cases, p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.p<0.001), LMP1 (43 to 54 cases, p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.p=0.001) and EBER-ISH (43 to 56 cases, p=0.07). This study showed that TMA is a reliable method to investigate cellular and viral expression in HL. Core duplication is an important strategy to improve TMA efficacy. Additionally, this study of LMP2A protein expression in 51 cases of pediatric HL showed low and discordant detection rates, regarding EBER-ISH and LMP1, pointing to the need to further investigate biological heterogeneity, as well as improving detection techniques.