Scientists at UC San Diego have discovered how cells of higher organisms change the speed at which they move, a basic biological discovery that may help researchers devise ways to prevent cancer cells from spreading throughout the body.

The discovery reported by the UCSD scientists in Proceedings of the National Academy of Sciences (PNAS) and published Aug. 3 on the journals Web site describes forces and energy exerted by the cells as they traveled across an elastic substrate. In videos recorded as the cells moved, each looked like an irregularly shaped water balloon attached firmly on two sticky sections while periodically protruding in the forward direction and withdrawing from the trailing end.

In humans and other mammals, cell motility is essential for many physiological processes such as tissue renewal and the function of the immune system. Cell motility also is an essential part of embryonic development as fetal cells undergo an orchestrated migration to form functioning tissues and organs. Poorly regulated cell motility during embryonic development may result in some neurological diseases and birth defects such as cleft palate of the mouth. UCSDs new findings may eventually be used to better understand and possibly treat such conditions and suggest possible new cancer treatments aimed at inhibiting the metastatic spreading of some cancer tumors.

Cells of all higher, or eukaryotic, species move in response to external stimuli. This movement is made possible by a series of inter-related biochemical reactions, some of which remodel the internal skeleton and others that add and remove adhesion points at strategic positions on the outer membrane. Regardless of their size or shape, cells use what cell biologists call the cell motility cycle to take one step per cycle: first, the cell extends its leading margin over the substratum forming a pseudopod or foot-like extension; secondly, the tip of the pseudopod develops an adhesion poin
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Contact: Rex Graham
ragraham@ucsd.edu
858-822-3075
University of California - San Diego
3-Aug-2007