IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Epigenetic differences in breast tumors with different cut-off levels for ER staining
Autor/es:
BRANHAM MT; LAURITO S; TELLO O; GAGO FE; OROZCO J; ROQUE M
Lugar:
Londres
Reunión:
Simposio; International Conference of Triple Negative Breast Cancer.; 2013
Resumen:
Breast cancer is a group of clinically, histopathologically and molecularly heterogeneous diseases, with different outcomes and responses to treatment. ER-/PR-/HER2- is an immunohistochemical description of breast cancers with a triple negative staining for ER, PR and HER2. These tumors (TN) have an aggressive clinical behavior and poor prognosis. How to define ER negativity remains a controversial topic. In the past investigators and clinicians considered 10% or superior nuclear staining as the cut-off for defining ER+ tumors. Actual guidelines recommend to decrease the cut-off level to 1%. However, recent findings suggest that almost half of tumors staining between 1%?9% have molecular characteristics of a basal-like phenotype. The hypermethylation of CpG islands (CpGI) is a common epigenetic alteration in breast cancer, and it is known that aberrant methylation profiles are specific for breast cancer subtypes. Objective: To analyze whether breast tumors with different ER staining cut-off levels, present differences in: methylation profiles, genomic stability of BAT26 marker and/or BRCAness phenotype. For this purpose we included 97 invasive ductal tumors, from which 19 had