Radiation Biology

Data

Official data in SubjectManager for the following academic year: 2024-2025

Topic

The course will focus on the better understanding of radiation effects on the whole organisms, tissues and cells, as well as on the cellular causes leading to the death of normal and malignant cells. This helps to understand why a given dose of radiation induces tumors in one case while destroys tumor cells in another case. On the basis of radiobiological knowledge one can develop new therapeutic modalities to improve the survival of cancer patients. Radiation biology helps us to understand how and why ionizing radiation can be used to examine healthy and pathological cell structures and to diagnose and treat various diseases.

The aim of radiation therapy is to kill tumor cells without seriously damaging normal tissues. The death of normal cells leading to the development of early and late normal tissue sequels strongly influences the amount of total and fraction doses deliverable to the malignant tissues and by this way the success of radiation therapy. We will describe factors and protocols affecting and suitable to predict radiation-induced reactions in healthy and malignant cells. The effect of dose rate, total- and fraction dose, as well as treatment time on the radiation response of normal and tumor cells will be discussed, too. We will describe in details those new radiotherapy approaches (accelerated-, hyper-fractionated, etc. radiotherapy) which were developed on radiobiological backgrounds. We will discuss those new therapeutic modalities such as gene therapy which can be efficiently combined with radiation therapy. Using up to date methodologies the radiation sensitivity of normal and malignant tissues might be predicted before the onset of radiation therapy and radiation regimens can be adjusted to individual needs. This can improve the survival chances of tumor patients.

Finally, we will discuss the radiation protection measures necessary to minimize the damaging effect of ionizing radiation.

Lectures

• 1. The importance of radiobiology in clinical diagnostics and therapy. Types of ionizing radiation, natural and artificial sources of radiation. - Sáfrány Géza
• 2. Cellular radiation damages, linear energy transfer and the relative biological effect. - Sáfrány Géza
• 3. Repair of cellular damages at the cellular level, the effect of dose rate on DNA repair. - Sáfrány Géza
• 4. The effect of oxygen on the survival of cells, radio-sensitizing agents, bioreductive drugs. - Sáfrány Géza
• 5. Acute radiobiological injuries in humans and in experimental animal models. - Sáfrány Géza
• 6. Epidemiology and molecular background of radiation-induced tumors. - Sáfrány Géza
• 7. Proliferative organization of normal tissues. Dose-effect relationships in normal tissues. - Sáfrány Géza
• 8. The radiobiological background of fractionated radiotherapy, the importance and application of the linear-quadratic approach in tumor treatment. - Sáfrány Géza
• 9. The role of treatment duration, total and fraction dose in radiotherapy. - Sáfrány Géza
• 10. Radiobiological principles of low and high-dose rate brachytherapy. - Sáfrány Géza
• 11. Risks of occupational exposure to radiation: dose limit in radiation protection. - Sáfrány Géza
• 12. Gene therapy of malignant tumors: combined modality treatments with radio- chemo- and gene therapy. - Sáfrány Géza

Practices

Seminars

• 1. Basics of radio-physics and radiochemistry: dosimetry, radiolysis, formation of free radicals, direct and indirect effects of radiation. - Sáfrány Géza
• 2. Cell death due to ionizing radiation, survival curves. - Sáfrány Géza
• 3. Radio-protective agents. - Sáfrány Géza
• 4. Genetic and fetal effects of ionizing radiation. - Sáfrány Géza
• 5. Molecular biological principles of tumor development. - Sáfrány Géza
• 6. The Chernobil nuclear accident and its consequences. - Sáfrány Géza
• 7. Proliferation of tumor cells, factors influencing tumor development. - Sáfrány Géza
• 8. Early and late side-effects of radiotherapy. - Sáfrány Géza
• 9. Alternative radiotherapeutic applications: accelerated-, hyper- and hypo-fractionated radiotherapy, particle radiations. - Sáfrány Géza
• 10. The risk of repeated radiotherapy. - Sáfrány Géza
• 11. Targeted and individual tumor therapy, estimating radiosensitivity, predictive assays. - Sáfrány Géza
• 12. Doses and risks in radiology and imaging diagnostics. - Sáfrány Géza

Reading material

Obligatory literature

Radiation Biology: A Handbook for Teachers and Students. International Atomic Energy Agency, Vienna, 2010; http://www.iaea.org/books

Literature developed by the Department

Notes

Recommended literature

http://radiationbiology.arc.nasa.gov/index.html

http://www.rtstudents.com/students/radiation-biology.htm

Conditions for acceptance of the semester

In the case of maximum 2 unexcused absences the student is allowed to take the exam.

Mid-term exams

Test exam at the end of the course; oral consultation at halfway

Making up for missed classes

Joining later seminars, individual consultations.

Exam topics/questions

Multiple choice test for checking the acquisition of course material is given at the end of semester. Questions include material discussed in lectures and seminars. It is important to know that part of the material cannot be found in textbooks.

Examiners

Instructor / tutor of practices and seminars

• Sáfrány Géza