Lori Rice, Ph.D.
Research Assistant Professor, Department of Radiation Oncology
Abstract
Every cell in our bodies is directed to perform specific tasks by its genes. These functions include making structural proteins, secreting insulin, or burning energy as fuel. Another function is replication, when “parent” cells divide to form more cells as needed. All these processes are orchestrated in a precise way by our DNA. Double stranded helixes, organized into chromosomes, carry the same code in every cell, but each cell type activates only a specific set of those genes. Damage to the DNA strands, by breakage or mistakes when code is copied, can cause damage to living organisms. Damage to the replication process can lead to cancer. Chemicals and high energy (ionizing) radiation are forces outside of the body that can damage DNA. Every day, we are exposed to radiation from sources such as sunlight, radios, microwaves, even light bulbs, but these are of relatively low energy and easily shielded. We are also greatly protected from high energy radiation from solar flares and cosmic radiation by our atmosphere, where most particles are either trapped or reflected back into space. At higher altitudes, the atmosphere is thinner and offers less protection. This poses a challenge for space flights that go beyond Low Earth Orbit (LEO), as when traveling to the moon and beyond. We need to know how much damage might occur on long term missions and how to protect astronauts from the high energy radiation they will encounter. We know that astronauts will be at greater risk of cancer and degenerative nerve diseases due to space radiation exposure. Our team is developing tests to measure DNA damage and products that might be used to offer protection. To improve our understanding of radiation damage to DNA, we can build instruments to simulate space radiation here on Earth and design experiments to expose DNA, cells, and research animals. We can study changes in the DNA at different doses. Our team has developed a small protein that mimics the effects of a natural growth factor. It is showing promise in providing protection to living cells and organisms. In addition, we have developed diagnostic tests to measure DNA damage in blood after an exposure event. This will also be important for people who have been exposed to a release of radioactive substances, like from a nuclear power plant, or who are undergoing medical radiation treatments. In this way, we can determine who might need supportive care. It will also allow us to monitor astronauts returning from missions to the International Space Station and beyond.
Speaker Bio
Dr. Lori Rice is a molecular biologist at the UF Health Cancer Center, studying radiation effects. The goal of this work is to improve the effectiveness of radiation therapy on cancer cells while minimizing injury to non-cancer cells. Measuring DNA damage after radiation will help predict patient response to treatment and evaluate effects experienced by astronauts after space flights. As a strategy to provide radiation protection, the team is developing small proteins (peptides) that may prevent or reduce damage from occurring.
Florida’s State Academic Standards for Science
SC.912.L.16.8
Explain the relationship between mutation, cell cycle, and uncontrolled cell growth potentially resulting in cancer.
SC.912.L.16.10
Evaluate the impact of biotechnology on the individual, society and the environment, including medical and ethical issues.
SC.912.N.1.4
Identify sources of information and assess their reliability according to the strict standards of scientific investigation.
SC.912.N.1.7
Recognize the role of creativity in constructing scientific questions, methods and explanations.
SC.912.N.1.6
Describe how scientific inferences are drawn from scientific observations and provide examples from the content being studied.
SC.912.L.16.3
Describe the basic process of DNA replication and how it relates to the transmission and conservation of the genetic information.
