LABORATORY RESEARCH Epigenetic and Transcriptional Determinants of the Human Breast Scientists generated epigenomic and transcriptional profiles from primary human breast cell types isolated from disease-free human subjects. From these data they define a comprehensive human breast transcriptional network, including a set of myoepithelial- and luminal epithelial-specific intronic retention events. [Nat Commun] Full Article | Press Release APOBEC3B Expression in Breast Cancer Reflects Cellular Proliferation, While a Deletion Polymorphism Is Associated with Immune Activation Investigators confirmed that APOBEC3B (A3B) expression is associated with aggressive clinicopathologic characteristics and adverse outcomes and show that A3B expression is highly correlated with proliferative features (mitosis and cell cycle-related gene expression) in breast and 15 of 16 other solid tumor types. [Proc Natl Acad Sci USA] Abstract | Full Article Wnt/β-Catenin Small Molecule Inhibitor CWP232228 Preferentially Inhibits the Growth of Breast Cancer Stem-Like Cells Researchers show that the level of Wnt/β-catenin signaling in breast cancer stem cells is relatively higher than in bulk tumor cells, contributing to a relatively higher level of therapeutic resistance. [Cancer Res] Abstract Cytoplasmic p27 Promotes Epithelial-Mesenchymal Transition and Tumor Metastasis via STAT3-Mediated Twist1 Upregulation Cell cycle-defective phosphomimetic phosphorylation of p27 at threonine 157 (T157) and T198 activates STAT3 (signal transducer and activator of transcription 3) to induce a TWIST1-dependent epithelial-mesenchymal transition in human mammary epithelial cells and increases breast and bladder cancer invasion and metastasis. [Oncogene] Full Article PEGylated-Thymoquinone-Nanoparticle Mediated Retardation of Breast Cancer Cell Migration by Deregulation of Cytoskeletal Actin Polymerization through miR-34a Scientists provide direct evidence that thymoquinone (TQ)-nanoparticles showed more efficiency in killing cancer cells as well as proved to be less toxic to normal cells at a significantly lower dose than TQ. [Biomaterials] Abstract Ski Regulates Hippo and TAZ Signaling to Suppress Breast Cancer Progression Researchers investigated the mechanism(s) underlying the tumor suppressor activity of Ski and found that Ski suppressed the activity of the Hippo signaling effectors TAZ and YAP to inhibit breast cancer progression. [Sci Signal] Abstract The Tyrosine Phosphatase PTPN14 (Pez) Inhibits Metastasis by Altering Protein Trafficking Investigators found that the tyrosine phosphatase PTPN14 suppressed metastasis by reducing intracellular protein trafficking through the secretory pathway. Knocking down PTPN14 in tumor cells or injecting the peritoneum of mice with conditioned medium from PTPN14-deficient cell cultures promoted the growth and metastasis of breast cancer xenografts. [Sci Signal] Abstract CLINICAL RESEARCH Pertuzumab, Trastuzumab, and Docetaxel in HER2-Positive Metastatic Breast Cancer In patients with metastatic breast cancer that is positive for human epidermal growth factor receptor 2 (HER2), progression-free survival was significantly improved after first-line therapy with pertuzumab, trastuzumab, and docetaxel, as compared with placebo, trastuzumab, and docetaxel. The secondary end points of overall survival, investigator-assessed progression-free survival, independently assessed duration of response, and safety are reported. [New Engl J Med] Full Article | Press Release Evidence for Biological Effects of Metformin in Operable Breast Cancer: Biomarker Analysis in a Pre-Operative Window of Opportunity Randomized Trial Investigators examined biomarker effects of metformin in primary breast cancer in a preoperative window of opportunity trial. Non-diabetic women with operable invasive breast cancer were randomized to receive open label pre-operative metformin or as controls. [Breast Cancer Res Treat] Abstract |