52P - Characterization of B cells infiltrating human breast cancer

Date 08 May 2014
Event IMPAKT 2014
Session Welcome reception and Poster Walk
Topics Breast Cancer
Pathology/Molecular Biology
Presenter Soizic Garaud
Citation Annals of Oncology (2014) 25 (suppl_1): i17-i18. 10.1093/annonc/mdu067
Authors S. Garaud1, L. Buisseret1, C. Gu-Trantien1, J. Lodewyckx1, H. Duvillier1, L. Craciun2, D. Larsimont2, K. Willard-Gallo1
  • 1Molecular Immunology, Institut Jules Bordet, Université Libre de Bruxelles, 1000 - Brussels/BE
  • 2Anatomie Pathologique, Institute Jules Bordet, 1000 - Brussels/BE

Abstract

Recent advances in tumor immunology show an important link exists between tumor infiltrating lymphocytes (TIL) and patient outcome. In breast cancer (BC) more extensive lymphocyte infiltration is associated with a better prognosis and also predicts the response to pre-operative chemotherapy. Our recent work found that tertiary lymphoid structures (TLS), composed of B cells, CD4 follicular helper T (T FH ) cells and dendritic cells, are present in BC. CD4 T FH cells located in TLS adjacent to the tumor bed of extensively infiltrated tumors are associated with a good clinical outcome. This important Tfh/TLS presence suggests that B cells may also play a role in generating effective anti-tumor immune responses. We therefore undertook to fully characterize B cells infiltrating human BC. Flow cytometric analysis of fresh tumor homogenates detected an increase in CD45 leukocytes in all BC subtypes compared with normal and non-tumor non-adjacent (NANT) breast tissue irrespective of lymphocyte infiltration levels. Infiltrating B cells were also elevated in tumors, particularly in extensively infiltrated high proliferative subtypes. CD45/CD19/CD38/IgD labeling revealed that approximately 50 of the infiltrating B cells are memory cells, which contrasts with