Molecular Profiling of Human Mammary Gland Links Breast Cancer Risk to a p27+ Cell Population with Progenitor Characteristics Early full-term pregnancy is one of the most effective natural protections against breast cancer. The authors found significant differences in CD44+ progenitor cells, where the levels of many stem cell-related genes and pathways, including the cell-cycle regulator p27, are lower in parous women without BRCA1/BRCA2 mutations. [Cell Stem Cell] Abstract | Graphical Abstract Lineage Tracing Reveals Multipotent Stem Cells Maintain Human Adenomas and the Pattern of Clonal Expansion in Tumor Evolution Researchers identified multipotential stem cells within human colorectal adenomas and use methylation patterns of nonexpressed genes to characterize clonal evolution. [Proc Natl Acad Sci USA] Abstract PPARγ Maintains ERBB2-Positive Breast Cancer Stem Cells Results show that the peroxisome proliferator-activated receptor-γ (PPARγ) pathway is critical for the cancer stem cell properties of ERBB2-positive breast cancer cells. [Oncogene] Full Article The Pluripotency Factor Nanog Promotes Breast Cancer Tumorigenesis and Metastasis To elucidate the physiological roles of Nanog in tumorigenesis, researchers developed an inducible Nanog transgenic mouse model, in which the expression of Nanog in adult tissues can be induced via LoxP/Cre-mediated deletion. Their findings indicate that overexpression of Nanog in the mammary gland is not sufficient to induce mammary tumor. However, when coexpressed with Wnt-1 in the mouse mammary gland, it promotes mammary tumorigenesis and metastasis. [Oncogene] Abstract IMP1 Promotes Tumor Growth, Dissemination, and a Tumor-Initiating Cell Phenotype in Colorectal Cancer Cell Xenografts Scientists demonstrate that Igf2 mRNA binding protein 1 (IMP1) overexpression decreases E-cadherin expression, promotes survival of single tumor cell-derived colonospheres, and promotes enrichment and maintenance of a population of CD24+CD44+ cells, signifying that IMP1 overexpressing cells display evidence of loss of epithelial identity as well as enhancement of a tumor-initiating cell phenotype. [Carcinogenesis] Abstract Metalloproteinase-Disintegrin ADAM12 Is Associated with a Breast Tumor-Initiating Cell Phenotype Researchers found that ADAM12L, but not the alternative splice variant ADAM12S, is a part of stromal, mammosphere, and epithelial-to-mesenchymal transition gene signatures, which are all associated with breast tumor-initiating cells. [Breast Cancer Res Treat] Abstract Identification of Cancer Stem-Like Side Population Cells in Purified Primary Cultured Human Laryngeal Squamous Cell Carcinoma Epithelia Findings suggest that the primary cultured and purified laryngeal squamous cell carcinoma cells (LSCCs) contain cancer stem-like side population cells, which may serve as a valuable model for cancer stem cell research in LSCC. [PLoS One] Full Article Pulmonary Fibroblasts Induce Epithelial Mesenchymal Transition and Some Characteristics of Stem Cells in Non-Small Cell Lung Cancer Investigators aimed to clarify the role of fibroblasts in tumor progression in non-small cell lung cancer (NSCLC). Fibroblasts were associated with increased malignant potential and the acquisition of stemness in NSCLC tumors. [Ann Thorac Surg] Abstract  |