LABORATORY RESEARCH Repurposing of Bisphosphonates for the Prevention and Therapy of Nonsmall Cell Lung and Breast Cancer Scientists show that bisphosphonates inhibit colony formation by HER1ΔE746-A750-driven HCC827 nonsmall cell lung cancer and human epidermal growth factor receptor (HER)1wt-expressing MB231 triple negative breast cancers, but not by HERlow-SW620 colon cancers. [Proc Natl Acad Sci USA] Abstract | Press Release Hypoxia-Inducible Factors Are Required for Chemotherapy Resistance of Breast Cancer Stem Cells Scientists demonstrate that hypoxia-inducible factor (HIF) expression and transcriptional activity are induced by treatment of breast cancer cell lines with paclitaxel or gemcitabine. Chemotherapy-induced HIF activity enriched the breast cancer stem cell population through interleukin-6 and interleukin-8 signaling and increased expression of multidrug resistance 1. [Proc Natl Acad Sci USA] Abstract | Full Article KAP1 Promotes Proliferation and Metastatic Progression of Breast Cancer Cells KAP1 silencing in breast cancer cells reduced proliferation and inhibited the growth and metastasis of tumor xenografts. Conversely, KAP1 overexpression stimulated cell proliferation and tumor growth. [Cancer Res] Abstract LRH-1 Controls Proliferation in Breast Tumor Cells by Regulating CDKN1A Gene Expression Scientists report that liver receptor homolog-1 (LRH-1) inhibition affects two- and three-dimensional cell proliferation of different types of breast cancer cells, including estrogen receptor α-positive and triple-negative cells. [Oncogene] Abstract RUNX1, a Transcription Factor Mutated in Breast Cancer, Controls the Fate of ER-Positive Mammary Luminal Cells Conditional knockout of Runx1 in mammary epithelial cells (MECs) by MMTV-Cre led to a decrease in luminal MECs, largely due to a profound reduction in the estrogen receptor (ER)-positive mature luminal subpopulation, a phenotype that could be rescued by loss of either Trp53 or Rb1. [eLife] Full Article Cooperation between BRCA1 and Vitamin D Is Critical for Histone Acetylation of the p21waf1 Promoter and Growth Inhibition of Breast Cancer Cells and Cancer Stem-Like Cells Scientists report that two non-calcemic analogues of 1α,25-dihydroxyvitamin D3 collaborate with BRCA1 in mediating growth inhibition of breast cancer cells and breast cancer stem-like cells. [Oncotarget] Full Article Exosome-Mediated Transfer of miR-10b Promotes Cell Invasion in Breast Cancer Scientists demonstrate that microRNA carrying exosomes can be transferred among different cell lines through direct uptake. miR-10b is highly expressed in metastatic breast cancer MDA-MB-231 cells as compared to non-metastatic breast cancer cells or non-malignant breast cells; it is actively secreted into medium via exosomes. [Mol Cancer] Abstract | Full Article Combination Therapy Targeting Ectopic ATP Synthase and 26S Proteasome Induces ER Stress in Breast Cancer Cells Scientists investigated the anticancer effects of the ATP synthase inhibitor citreoviridin on breast cancer cells through proteomic approaches and revealed that differentially expressed proteins in cell cycle regulation and in the unfolded protein response were functionally enriched. [Cell Death Dis] Full Article MTDH Mediates Trastuzumab Resistance in HER2 Positive Breast Cancer by Decreasing PTEN Expression through an NFκB-Dependent Pathway Since metadherin (MTDH) promotes malignant phenotype of breast cancer, investigators sought to define whether MTDH promotes trastuzumab resistance by decreasing chromosome 10 (PTEN) expression through an NFκB-dependent pathway. [BMC Cancer] Full Article FOXD1 Promotes Breast Cancer Proliferation and Chemotherapeutic Drug Resistance by Targeting p27 Researchers found that FOXD1 is up-regulated in breast cancer tissues. Depletion of FOXD1 expression decreases the ability of cell proliferation and chemoresistance in MDA-MB-231 cells, whereas overexpression of FOXD1 increases the ability of cell proliferation and chemoresistance in MCF-7 cells. [Biochem Biophys Res Commun] Abstract CLINICAL RESEARCH Safety and Preliminary Evidence of Biologic Efficacy of a Mammaglobin-A DNA Vaccine in Patients with Stable Metastatic Breast Cancer Fourteen subjects were treated with the Mammaglobin-A DNA vaccine and no significant adverse events have been observed. Eight of 14 subjects were HLA-A2+, and the CD8 T-cell response to vaccination was studied in detail. [Clin Cancer Res] Abstract | Press Release Combination of Letrozole, Metronomic Cyclophosphamide and Sorafenib Is Well-Tolerated and Shows Activity in Patients with Primary Breast Cancer Investigators assessed whether the combination of letrozole, metronomic cyclophosphamide and sorafenib is well tolerated and shows activity in primary breast cancer. [Br J Cancer] Abstract |