LABORATORY RESEARCH Dual Functions of the Homeoprotein DLX4 in Modulating Responsiveness of Tumor Cells to Topoisomerase II-Targeting Drugs Researchers identified that topoisomerase IIα expression is induced by DLX4, a homeoprotein that is overexpressed in breast and ovarian cancers. [Cancer Res] Abstract Dual Blockade of HER2 in HER2-Overexpressing Tumor Cells Does Not Completely Eliminate HER3 Function Scientists hypothesized that suppression of HER3 would synergize with dual blockade of HER2 in breast cancer cells sensitive and refractory to HER2 antagonists. [Clin Cancer Res] Abstract Prevention of Nodal Metastases in Breast Cancer following the Lymphatic Migration of Paclitaxel-Loaded Expansile Nanoparticles Given the potential for targeted drug delivery to result in more efficacious locoregional control with less morbidity, the authors assessed the ability of drug-loaded polymeric expansile nanoparticles to migrate from the site of tumor to regional lymph nodes, locally deliver a chemotherapeutic payload, and prevent primary tumor growth as well as lymph node metastases. [Biomaterials] Abstract Knockdown of Prolyl-4-Hydroxylase Domain 2 Inhibits Tumor Growth of Human Breast Cancer MDA-MB-231 Cells by Affecting TGF-β1 Processing Investigators established prolyl-4-hydroxylase domain enzymes 2 knockdown clones of MDA-MB-231 breast cancer cells and analyzed their tumor forming potential in a SCID mouse model. [Int J Cancer] Abstract Maintenance of S-Nitrosothiol Homeostasis Plays an Important Role in Growth Suppression of Estrogen Receptor Positive Breast Tumors Protein denitrosylation by thioredoxin reductase is key for maintaining S-nitrosothiol (SNO) homeostasis, although its role in tumor progression is unknown. Therefore, researchers assessed the role of altered SNO homeostasis in breast cancer cells. [Breast Cancer Res] Full Article Cell Specific CD44 Expression in Breast Cancer Requires the Interaction of AP-1 and NFκB with a Novel cis-Element Scientists identified a novel cis-element of the CD44 directs gene expression in breast cancer cells in a cell type specific manner. They further identified key trans-acting factor binding sites and nuclear factors AP-1 and NFκB that are involved in the regulation of cell-specific CD44 expression. [PloS One] Full Article Feline Mammary Carcinoma Stem Cells Are Tumorigenic, Radioresistant, Chemoresistant and Defective in Activation of the ATM/p53 DNA Damage Pathway Cancer stem cells were identified in a feline mammary carcinoma cell line by demonstrating expression of CD133 and utilizing the tumor sphere assay. A population of cells was identified that had an invasive, mesenchymal phenotype, expressed markers of pluripotency and enhanced tumor formation in the NOD-SCID mouse and chick embryo models. [Vet J] Full Article Activating HER2 Mutations in HER2 Gene Amplification Negative Breast Cancer Data from eight breast cancer genome-sequencing projects identified 25 patients with HER2 somatic mutations in cancers lacking HER2 gene amplification. To determine the phenotype of these mutations, investigators functionally characterized 13 HER2 mutations using in vitro kinase assays, protein structure analysis, cell culture, and xenograft experiments. [Cancer Discov] Abstract | Press Release CLINICAL RESEARCH Reproductive Factors and Risk of Estrogen Receptor Positive, Triple-Negative, and HER2-Neu Overexpressing Breast Cancer among Women 20-44 Years of Age Using data from a population-based case-control study of women 20-44 years of age, researchers assessed the relationships between various reproductive factors and risk of estrogen receptor positive, triple-negative, and HER2-overexpressing breast cancers. [Breast Cancer Res Treat] Abstract Capecitabine and Oxaliplatin in Combination as First- or Second-Line Therapy for Metastatic Breast Cancer: A Wisconsin Oncology Network Trial This Phase II study evaluated the combination of capecitabine and oxaliplatin among patients with metastatic breast cancer being treated in the first- or second-line setting. [Cancer Chemother Pharmacol] Abstract |