University of Illinois researchers believe the pig may hold answers for scientists studying breast cancer, a disease that kills 500,000 women worldwide each year.
While extraordinary advances in the understanding of cancer's molecular basis have occurred in the past 10 years, current models for drug testing are not keeping pace.
"The failure of current animal models to predict the human response is a critical bottleneck and is likely to become the limiting factor in the development of effective new cancer therapies," says Laurie Rund, U of I research professor in animal science. "To take advantage of the advances in novel therapeutic design, we need to find a more physiological and predictive animal model for cancer."
Rund and U of I colleague Lawrence Schook, in collaboration with Jason Chesney and principal investigator Geoff Clark of the Brown Cancer Center – University of Louisville, have been awarded a National Institutes of Health EUREKA (Exceptional, Unconventional Research Enabling Knowledge Acceleration) grant to develop a transgenic swine model for cancer.
Transgenic pigs hopefully can be made to lose the expression of tumor suppressors
Under the four-year project entitled, "Oncopigs as a Better Model for Human Cancer," collaborators will use state-of-the-art technology to generate transgenic pigs that can be induced to lose the expression of three major tumor suppressors simultaneously in the breast. "These genetic defects are often found in breast cancer, particularly in Triple Negative breast cancer," says Rund. "Triple Negative breast cancer is especially aggressive and difficult to treat. It has a high morbidity rate and affects African American women at almost three times the rate of the general population."
Rund and colleagues have discovered that it takes five to six genetic defects to convert a normal pig cell into a tumor cell – just like humans. However, mouse cells, which have been used in many previous studies, can be transformed into tumor cells by as little as two genetic defects. In addition, pigs are similar to humans because they can live for decades and have a very low rate of spontaneous cancer. This is in contrast to rodent-based cancer models, where life span is limited to a few years and the spontaneous development of cancer is high. Rund says this study could allow their team to validate the pig as a superior model to study human cancer.
If this works, doctors using pigs can study more types of cancer
"If this works, we can study more types of cancer using the pig model," says Rund. "It's the first transgenic pig model for breast cancer that I know of, although pigs have been used extensively in biomedical research for years."
Investigators testing novel, unconventional hypotheses or major methodological or technical challenges are sought after to receive NIH Eureka grants. "Only 30 EUREKA grants are awarded each year," said Lawrence Schook, Gutgsell professor of animal sciences and director of the Division of Biomedical Sciences. "We are honored to receive this award as it targets exceptionally innovative research that will have a substantial impact on the scientific community."