Metastasis when cancer cells dissociate from the original tumor and migrate via the blood stream to colonize distant organs is the main cause of cancer death. A team of scientists at the Weizmann Institute of Science has now revealed new details about the mechanisms controlling metastasis of breast cancer cells. Their findings, published recently online in Nature Cell Biology, add significantly to the understanding of metastasis and may aid, in the future, in the development of anti-cancer drugs.
For a cell such as a cancer cell to migrate, it first must detach itself from neighboring cells and the intercellular material to which it is anchored. Before it can do this, it receives an order from outside the cell saying: 'prepare to move.' This signal takes the form of a substance called a growth factor, which, in addition to controlling movement, can activate a number of processes in the cell including division and differentiation. The growth factor attaches to a receptor on the cell wall, initiating a sequence of changes in the cellular structure. The cells internal skeleton an assembly of densely-packed protein fibers comes apart and the protein fibers then form thin threads on the outside of the cell membrane that push the cell away from its neighbors. In addition, a number of protein levels change: some get produced in higher quantities and some in less.
To understand which proteins are modulated by the growth factor and the nature of the genetic mechanisms involved in cancer cell migration, a team of researchers pooled their knowledge and resources. This team, headed by Prof. Yosef Yarden of the Weizmann Institutes Biological Regulation Department and his research group, including Drs. Menachem Katz, Ido Amit and Ami Citri; Tal Shay, a student in the group of Prof. Eytan Domany of the Physics of Complex Systems Department; and Prof. Gideon Rechavi of the Chaim Sheba Medial Center at Tel Hashomer.