OU Cancer Institute targeting new cancer therapy

DIANE CLAY
Special to The Sun

OKLAHOMA CITY March 27, 2008 11:56 am

— Researchers at the OU Cancer Institute have found a way to turn off a protein that causes cancerous tumors to grow. The new approach could lead to better and more complete therapies for cancer patients. The research appears this month in the online version of the journal Gastroenterology.
Cancer biologist Shrikant Anant and Dr. Courtney Houchen, both of Edmond; and their research team at the University of Oklahoma Health Sciences Center found that when they disrupted the genetic signals leading to the creation of a critical protein, they not only stopped the protein expression but caused cancer cells to die and tumors to stop growing.
Researchers discovered the potential cancer therapy when they tested a hunch that a critical RNA binding protein, called Musashi-1, appears in rapidly growing cells in cancerous tumors. Until now, scientists had believed the protein only was located in adult stem cells, which divide slowly in tumors. Adult stem cells are essential building blocks for many organs and work to replenish dying cells and regenerate damaged tissues.
By targeting the Musashi-1 protein, OU scientists killed all of the cancer cells in the tumor, including the “stem cells,” which have the ability to wait until after chemotherapy or radiation treatments to begin dividing. Researchers believe these stem cells often are responsible for the return of cancer after treatment. Current therapies generally do not target the “tumor stem cells.”
“Killing cancer cells is like cutting off your hair. If you don’t cut the root, it will grow back,” Houchen said. “Chemotherapy is geared toward attacking rapidly dividing cells, so dormant stem cells potentially sit there and when therapy is over, they can activate.”
Researchers think the Musashi-1 protein is responsible for telling the cells to divide and grow. If they can inactivate the protein in a new therapy, it potentially would keep the stem cells from dividing and growing, and keep cancer from returning.
Houchen and Anant have tested their idea in the lab with cell culture systems and in animal tumor models with success.
If funding allows, researchers hope to have the necessary testing completed to begin the first phase of clinical trials in five to seven years.

DIANE CLAY is the media specialist for Univeristy of Oklahoma Health Sciences Center Public Affairs.