LABORATORY RESEARCH RUNX1 Prevents Estrogen-Mediated AXIN1 Suppression and Beta-Catenin Activation in ER-Positive Breast Cancer By depleting mammary epithelial cells of RUNX1 in vivo and in vitro, researchers demonstrated combinatorial regulation of AXIN1 by RUNX1 and estrogen. [Nat Commun] Full Article Non-Migratory Tumorigenic Intrinsic Cancer Stem Cells Ensure Breast Cancer Metastasis by Generation of CXCR4 Migrating Cancer Stem Cells Scientists showed that unlike highly metastatic cancer stem cells (mCSCs) residing in the breast tumor disseminating/peripheral regions, tumorigenic intrinsic CSCs (iCSCs) populate the inner mass of the tumor and are non-migratory. However iCSCs, via paracrine signaling, induce conversion of non-stem cancer cells to CSCs that are identical to the previously reported mCSCs, and in contrast to iCSCs, express chemokine receptor, chemokine receptor 4 (CXCR4), which is crucial for their metastatic potential. [Oncogene] Abstract The Acetyltransferase Tip60 Contributes to Mammary Tumorigenesis by Modulating DNA Repair Scientists demonstrated that Tip60 controls homologous recombination (HR)-directed DNA repair, and that Tip60 levels correlate inversely with a gene expression signature associated with defective HR-directed DNA repair. In human breast cancer data sets, Tip60 mRNA was downregulated, with low Tip60 levels correlating with p53 mutations in basal-like breast cancers. [Cell Death Differ] Full Article Histone Deacetylase Inhibition Reveals a Tumor-Suppressive Function of MYC-Regulated miRNA in Breast and Lung Carcinoma Investigators report that histone deacetylase (HDAC) inhibition in human breast and lung carcinoma cells activates an apoptotic mechanism mediated by microRNA (miRNA) and induced by the oncogene MYC. [Cell Death Differ] Abstract Inhibiting Notch Activity in Breast Cancer Stem Cells by Glucose Functionalized Nanoparticles Carrying γ-Secretase Inhibitors Investigators demonstrated that enhanced Notch signaling in breast cancer promotes self-renewal of cancer stem cells that display high glycolytic activity and aggressive hormone-independent tumor growth in vivo. [Mol Ther] Abstract | Full Article MicroRNA Expression Profiling Identifies Decreased Expression of miR-205 in Inflammatory Breast Cancer Researchers performed microRNA expression profiling in inflammatory breast cancer in comparison with locally advanced noninflammatory breast cancer. [Mod Pathol] Abstract Interaction with Pyruvate Kinase M2 Destabilizes Tristetraprolin by Proteasome Degradation and Regulates Cell Proliferation in Breast Cancer The authors identified tristetraprolin, an AU-rich, element-binding protein that regulates mRNA stability, as a new binding partner of pyruvate kinase M2. [Sci Rep] Full Article Growth of Human Breast Tissues from Patient Cells in 3D Hydrogel Scaffolds The authors describe a three-dimensional (3D) culture system that stimulates the outgrowth of morphologically complex and hormone-responsive mammary tissues from primary human breast epithelial cells. [Breast Cancer Res] Full Article | Press Release PKC Activation Sensitizes Basal-Like Breast Cancer Cell Lines to Smac Mimetics Investigators showed that the protein kinase C (PKC) activator TPA together with the Smac mimetic LBW242 induces cell death in two basal breast cancer cell lines that are resistant to Smac mimetic as single agent. [Cell Death Discov] Full Article CLINICAL RESEARCH Fulvestrant plus Palbociclib versus Fulvestrant plus Placebo for Treatment of Hormone-Receptor-Positive, HER2-Negative Metastatic Breast Cancer that Progressed on Previous Endocrine Therapy (PALOMA-3): Final Analysis of the Multicentre, Double-Blind, Phase III Randomized Controlled Trial Fulvestrant plus palbociclib was associated with significant and consistent improvement in progression-free survival compared with fulvestrant plus placebo, irrespective of the degree of endocrine resistance, hormone-receptor expression level, and PIK3CA mutational status. [Lancet Oncol] Abstract | Press Release |