Cell Cycle in Normal and Malignant Breast Epithelial Cells.

Abstract : Breast cancer is a disease where breast epithelial cells become refractory to appropriate growth and differentiation signals. It is likely that numerous genetic changes can contribute to malignant transformation, including mutations that alter the cell cycle regulatory machinery. We have therefore sought to characterize the function of both positive and negative cell cycle regulatory elements in normal and malignant breast epithelial cells. In particular, we have focused on cyclin E, a positive cell cycle regulators element already implicated in some breast malignancies and on a class of negative regulators of cyclin-dependent kinases (Cdks). Preliminary data indicate that both cyclin B and Cdk inhibitors are important in breast malignancy. malignancy.