According to UI Professor of Animal and Veterinary Science Gordon Woods, leader of the UI-Utah State University team that recently produced the first mule clone, the chemical changes necessary for the successful cloning provide new insight about what influences cell growth and activity. In addition, Woods, who also serves as director of the UI's Northwest Equine Reproduction Laboratory, said the horse provides a novel and effective model for studying cancer metastasis and other age-onset diseases in humans.
"The mortality rate for horses with metastatic cancer is 8 percent for all cancers and 0 percent for prostate cancer. By comparison, the mortality rate in humans is approximately 24 percent for all cancers, of which 13 to 14 percent are for prostate cancer," Woods said. "The contrasts and similarities between humans and horses at the cellular level provide a number of insights about how the relationship of certain chemicals in the body affect both normal and abnormal cell activity."
Calcium — more importantly, the relationship between the amount of calcium within each cell and outside each cell — is key. Members of the horse family have a lower amount of intracellular calcium than humans and a correspondingly slower rate of cell activity.
Woods said when his team first started its cloning work in 1998, only a very few of the implants resulted in pregnancies, and none of those progressed past the four-week point. Based on new information provided by Cancer2, a private corporation founded by Woods, the scientists agreed part of the problem was the relatively slow rate of cell activity in members of the horse family. Woods noted that the slow rate of cell activity may be why in vitro fertilization doesn't work in horses and may be why the cancer mortality rate among horses is so low.
In July 2001, however, the team supplemented the amount of calcium in the implanted clones. "We increased the calcium in the medium holding the embryos and saw a seven-fold increase in our week two pregnancy rates," Woods said. "We produced 19 pregnancies; the first baby has been born, and two more pregnancies are in the advanced stages."
The team concluded that the increase in calcium within the implanted clone cells directly impacted the speed of cell division. Understanding the role of calcium in equine cell activity was a direct result of work conducted by Cancer2. Cancer2 gifted the intellectual property to UI.
According to existing research, the amount of intracellular calcium is higher than normal in humans with metastasizing cancer. According to Woods' research, the amount of intracellular calcium is below normal in horses. Within Cancer2, Woods and his team have discovered a chemical that suppresses intracellular calcium. Abnormally high intracellular calcium is a root cause of abnormally high cell activity in aged humans.
"There are electrifying similarities between cancer metastasis and embryo division," said Woods. He said he is working toward critical testing of the effects of deficiencies in the suppressor in human clinical trials. "We've identified a suppressor of intracellular calcium and believe its deficiency is the root cause of abnormally high intracellular calcium."
Woods established the Northwest Equine Reproduction Laboratory on the UI campus in 1986. He had come full circle, having completed pre-veterinary courses at the UI in 1974. A few years later, he earned the D.V.M. degree from Colorado State University.
Woods returned to the Northwest briefly to practice veterinary medicine then moved east to complete a residency in large animal reproduction at the University of Pennsylvania under R. M. Kenney. Next, at the University of Wisconsin, he became a student of O. J. Ginther, and completed his master's and doctor's degrees under his direction.
Woods' first faculty assignment came in 1983 at the New York State College of Veterinary Medicine where he originated and directed Cornell's Laboratory of Equine Embryo Biology. He left Cornell in 1986 to set up the Northwest Equine Reproduction Laboratory on the UI campus.
EDITORS: The University of Idaho will provide a satellite feed with highlights from Thursday morning's news conference as well as file video between 12:30 and 12:45 p.m., PDT, at Ku band, AMC 3, Transponder 15, Polarity: Horizontal 87 degrees W, Downlink frequ. 12000, Audio 6.2/6.8. In addition, reporters from the United States can join the news conference by telephone by calling 800-553-0318; reporters from outside the U.S. can join by calling 612-288-0340.
CONTACTS: Kathy Barnard or Bill Loftus, University Communications, 208-885-6291, kbarnard@uidaho.edu or bloftus@uidaho.edu.
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