MARCH 31, 2011 -- A discovery by University of Oklahoma Health Sciences Center researchers may help unravel questions about why cancer cells reproduce so rapidly and could help lead to ways to block cancer growth.

The research is featured in the April issue of the scientific journal Nature Cell Biology.

Dr. Leonidas Tsiokas, an associate professor of cell biology in the OU College of Medicine, postdoctoral fellow Sehyun Kim and their colleagues focused on a key structure of the cell called the primary cilium. The primary cilium is a hair-like structure that protrudes from the cell wall. Unlike motile cilia, which are present in large numbers in cells, most cells have only one primary cilium.

Scientists already knew that this structure was lacking in rapidly reproducing cells like cancer cells and those responsible for other disorders and syndromes in which cells rapidly reproduce.  Tsiokas and his team identified a network of proteins responsible for determining the length of the primary cilia. They were then able to alter the length of the primary cilium; and by doing so, they discovered that changes in the length of the primary cilia affected cell growth.

In fact, when cells were induced to form abnormally long primary cilia, they did not proliferate as quickly as cells with primary cilia of normal length or those without a primary cilium. The finding suggests that the primary cilia may work as a physical barrier to stimuli that induce cell proliferation. 

“This discovery is exciting because it suggests that if we can manage to regulate ciliary length, we could in principle, control the proliferation of cancer cells,” Tsiokas said. “The study not only advances our understanding of the biological role of this ancient organelle, but also suggests new avenues to combat cancer and other proliferative disorders such as polycystic kidney disease.”

Cancer experts said the research is promising.

“Identifying the mechanisms by which normal cells proliferate is a key to understanding how tumors develop,” said Danny Dhanesekaran, Ph.D., Deputy Director for Basic Research at the Peggy and Charles Stephenson Oklahoma Cancer Center.

“This finding provides a novel approach for regulating cell growth and combating diseases such as cancer. This is a very important discovery,” said Marie Hanigan, Ph.D., a cancer cell biologist with the Cancer Center.