p27(Kip1) and stathmin share the stage for the first time.

Cell migration is essential for development, morphogenesis, tissue repair and tumor metastasis. p27(Kip1) and stathmin are two cell-cycle-regulatory proteins that were recently shown to play important roles in the regulation of cell migration. In this article, we discuss a new study that places p27(Kip1) and stathmin in the same pathway by showing that stathmin, a microtubule-regulatory protein, mediates the effects of p27(Kip1) on cell motility. These findings provide new insights into migration and metastasis of tumor cells and the relationship of these processes to cell proliferation.