Scientists from the University of Helsinki and from UCSF have exposed a cell pathway that breast tumor cells use to destruct local tissue neighborhood. Cancer cells may use this pathway to free themselves from mammary epithelial tissue architecture, to spread to surrounding tissues. The cell pathway, the researchers found, is a biochemical chain of events leading to activation of a protein-cleaving enzyme on the surface of the tumor cells.
Cancer rarely kills unless it evolves the ability to spread beyond the tissue in which it developed, to grow into surrounding healthy tissues. An important roadblock for tumor spread is membranous scaffolding, basement membrane, which lines epithelial cell layers in tissues. Normal epithelial cells and even early-stage tumor cells remain tightly tethered to basement membrane, which segregates healthy and likewise cancerous epithelial cells from surrounding tissues. Breakdown of this barrier allows tumor cells to escape from the tethers of the epithelium, launching a tumor invasion to healthy tissues.
Finnish scientists from the University of Helsinki, together with UCSF researchers, have identified a molecular pathway in breast tumor cells leading to activation of a protein-cleaving enzyme hepsin on the surface of breast tumor cells. Tumor cells use hepsin to chop basement membrane proteins - to break free from ties and matrix binding them to local neighborhood in their native epithelial tissue, the investigation suggests. The study will be published in the 16th January edition of the Proceedings of the National Academy of Sciences (PNAS).
"If we could delay or prevent a tumor from switching from one that grows in place to one that invades, then that would be a major milestone in cancer treatment," according to study co-author Zena Werb, PhD, a professor of anatomy at UCSF. Werb has for decades studied the ways in which the behavior of tumor cells is influenced by their surroun
|Contact: Dr. Juha Klefstrm|
University of Helsinki