Mapping the cellular and molecular heterogeneity of normal and malignant breast tissues and cultured cell lines.

Introduction: Normal and neoplastic breast tissues are comprised of heterogeneous populations of epithelial cells involving various degrees of maturation and differentiation. While cultured cell lines have been derived from both normal and malignant tissues, it remains unclear whether they retain a similar cellular heterogeneity as to that found within breast tissues.

Methods: We used 12 reduction mammoplasty tissues, 15 primary breast cancer tissues, and 20 human breast epithelial cell lines (16 cancer lines, 4 normal lines) to perform flow cytometry for CD44, CD24, epithelial cell adhesion molecule (EpCAM), and CD49f expression as well as immunohistochemistry, and in vivo tumor xenograft formation studies to extensively analyze the molecular and cellular characteristics of breast epithelial cell lineages.

A novel lung metastasis signature links Wnt signaling with cancer cell self-renewal and epithelial-mesenchymal transition in basal-like breast cancer.

The establishment of metastasis depends on the ability of cancer cells to acquire a migratory phenotype combined with their capacity to recreate a secondary tumor in a distant tissue. In epithelial cancers, such as those of the breast, the epithelial-mesenchymal transition (EMT) is associated with basal-like breast cancers, generates cells with stem-like properties, and enables cancer cell dissemination and metastasis. However, the molecular mechanism(s) that connects stem cell-like characteristics with EMT has yet to be defined.