Correlation Between In Vitro Chemotherapy Sensitivity And Parp-1 Expression In Patients With Breast Cancer.

10627 Background: Based on its potential use as a therapeutic target through PARP inhibitors expression of Poly-A-Ribose-Polymerase-1 (PARP-1) has come into scientific focus. Furthermore, it could be demonstrated that cytoplasmic PARP-1 expression varies depending on molecular breast cancer subtypes and that it correlates with an increased response to neoadjuvant taxane-anthrazykline containing chemotherapy (von Minckwitz et al., J Clin Oncol 2011). In-vitro-chemotherapy sensitivity and resistance assays (CSRAs) are a means to directly measure chemotherapy sensitivity in a given tumor uninfluenced by host factors. Methods: We conducted a systematic immunohistochemical tissue-microarray (TMA)-based analysis of 550 samples of invasive breast cancers to evaluate the expression of a set of molecular markers including estrogen receptor (ER), progesterone receptor (PR) and HER2 as well as PARP-1. Triple negative breast cancers (TNBC) were identified through lack of (over-)expression of ER, PR and HER2. All carc...