A team of researchers at the Weizmann Institute of Science in Rechovot has revealed new details about the mechanism by which cancerous cells migrate through the body. Such migration, called metastasis, is the leading cause of death among cancer patients.
A team of Israeli and foreign researchers pooled their knowledge and resources.
The findings, published recently in the online journal Nature Cell Biology, focused on metastasis in breast cancer cells.
A team of Israeli and foreign researchers pooled their knowledge and resources specifically in order to study the phenomenon of cancer cell migration. This team was headed by Prof. Yosef Yarden of the Weizmann Institute's Biological Regulation Department and his research group, including Drs. Menachem Katz, Ido Amit and Ami Citri.
Team members also included Tal Shay, a student in the Physics of Complex Systems Department at Weizmann, and Prof. Gideon Rechavi of the Chaim Sheba Medical Center at Tel HaShomer Hospital. Also involved was a research team from the Institute of Molecular Pathology and Immunology and the Medical Faculty at Porto University, Portugal; and individual researchers from the University of California at Davis, from Boston University and from GlaxoSmithKline in North Carolina.
The recently published results of this collaboration add significantly to the understanding of metastasis and may aid, in the future, in the development of anti-cancer drugs.
The researchers mapped all of the genetic changes that take place in the cancer cell after it receives a signal from a substance outside the cell that enables it to detach itself from neighboring cells and the intercellular material. The substance activates a number of processes in the cancerous cell, including changes in cell structure, division and differentiation. In their observations, the scientists discovered that a specific protein increases in the cell during these processes. That protein acts as a kind of plug, blocking the cell's ability to anchor on to other cells. This frees it to move, and, if it's a cancer cell, to metastasize to a new site in the body.
In experiments with genetically engineered cells, Prof. Yarden and his team showed that blocking production of the protein in question kept cells in their place, while overproduction of this protein plug increased their migration. The scientists also carried out tests on tumor samples taken from around 300 patients with inflammatory breast cancer, a rare but swift and deadly form of the disease. They found a strong correlation between high cell migration and levels of the "plug" protein. High levels of this protein, in turn, were associated with cancer metastasis to the lymph nodes - the first station of migrating cancer cells as they spread to other parts of the body.
According to Prof. Yarden, "The mechanism we identified is clinically important. It can predict the development of metastasis and possibly how the cancer will respond to treatment."