LABORATORY RESEARCH Profiles of Basal and Stimulated Receptor Signaling Networks Predict Drug Response in Breast Cancer Lines Scientists profiled signaling pathway activity in a collection of breast cancer cell lines before and after stimulation with physiologically relevant ligands, which revealed the variability in network activity among cells of known genotype and molecular subtype. [Sci Signal] Abstract Cell Type-Dependent Pathogenic Functions of Overexpressed Human Cathepsin B in Murine Breast Cancer Progression In order to evaluate the impact of tumor- or stromal cell-derived cysteine protease cathepsin B (CTSB) on Polyoma Middle T (PyMT)-induced breast cancer progression, investigators used in vivo and in vitro approaches to induce human CTSB overexpression in PyMT cancer cells or stromal cells alone or in combination. [Oncogene] Abstract Metastasis Tumor-Associated Protein 2 Enhances Metastatic Behavior and Is Associated with Poor Outcomes in Estrogen Receptor-Negative Breast Cancer Researchers hypothesized that metastasis tumor-assigned protein 2 (MTA2) enhances breast cancer progression. To test this, cell growth, soft-agar colony formation, migration, and in vivo metastasis were examined in MTA2-overexpressing and Vector control transfected estrogen receptor α-negative breast cancer cells. [Breast Cancer Res Treat] Abstract Low Molecular Weight Protein Tyrosine Phosphatase Isoforms Regulate Breast Cancer Cells Migration Through a RhoA Dependent Mechanism Low molecular weight protein tyrosine phosphatase (LMW-PTP) has been associated with cell proliferation control through dephosphorylation and inactivation of growth factor receptors such as platelet derived growth factor receptor and Ephrin Receptor A2, and with cellular adhesion and migration through p190RhoGap and RhoA. Investigators aimed to clarify the role of two main LMW-PTP isoforms in breast cancer tumorigenesis. [PLoS One] Full Article Herbacetin, a Constituent of Ephedrae Herba, Suppresses the HGF-Induced Motility of Human Breast Cancer MDA-MB-231 Cells by Inhibiting c-Met and Akt Phosphorylation Authors report that herbacetin suppressed hepatocyte growth factor-induced motility in human breast cancer MDA-MB-231 cells by inhibiting c-Met and Akt phosphorylation and directly inhibiting c-Met tyrosine kinase activity. [Planta Med] Abstract CLINICAL RESEARCH Phase I Trial of the Oral PARP Inhibitor Olaparib in Combination with Paclitaxel for First- or Second-Line Treatment of Patients with Metastatic Triple-Negative Breast Cancer This Phase I study evaluated the safety, tolerability and efficacy of olaparib, a potent oral Poly(ADP-ribose) polymerase (PARP) inhibitor, in combination with paclitaxel in patients with metastatic triple-negative breast cancer. [Breast Cancer Res] Abstract | Full Article Elevated Levels of Serum Tumor Markers CA 15-3 and CEA Are Prognostic Factors for Diagnosis of Metastatic Breast Cancers After primary treatments of locoregional breast cancers, serum cancer antigen (CA) 15-3 and/or carcinoembryonic antigen (CEA) concentrations were regularly measured, and systemic recurrences were identified in 351 patients between January 1999 and December 2009. The association between tumor marker levels at systemic recurrence and survival were investigated by univariate and multivariate analyses. [Breast Cancer Res Treat] Abstract Phase I-II Study of the Farnesyl Transferase Inhibitor Tipifarnib Plus Sequential Weekly Paclitaxel and Doxorubicin-Cyclophosphamide in HER2/Neu-Negative Inflammatory Carcinoma and Non-Inflammatory Estrogen Receptor-Positive Breast Carcinoma Tipifarnib (T) is a farnesyl transferase inhibitor that enhances the antineoplastic effects of cytotoxic therapy in vitro, has activity in metastatic breast cancer, and enhances the pathologic complete response rate to neoadjuvant doxorubicin-cyclophosphamide (AC) chemotherapy. Investigators, therefore, performed a phase I-II trial of T plus neoadjuvant sequential weekly paclitaxel and 2-week AC chemotherapy in locally advanced breast cancer. [Breast Cancer Res Treat] Abstract |