Basic research on chromosomal aberrations in cancer prevention, treatment and prognosis

Background: Chromosome breakage is a catastrophic event that can lead to the onset and development of cancer. Individual differences in sensitivity to radiation may explain the mechanism of drug resistance. Flash radiotherapy is a cutting-edge technology and has been a research hotspot in international tumor radiotherapy research in recent years.

Objective: To investigate the mechanism of radiation resistance, radioprotection, tumor metastasis and prognosis.

Methods: Peripheral blood was collected from 20 healthy people and irradiated with ⁶⁰Co gamma rays in vitro at a dose of 2.0 Gy to conduct a radiosensitivity study.The chromosomal aberrations of peripheral blood lymphocytes in 60 healthy subjects and 49 tumor patients before radiotherapy were analysed to study the quantitative relationship between radiation effects and radiation biomarkers.The dynamic effects of different radiation dose rates on the key biomarker “dicentric+ ring chromosome” were systematically analysed by analyzing the curves established for different radiation dose rates.

Results: The detection rate of chromosomal aberrations "dicentric + translocations" in tumor patients is relatively high. Under 2Gy irradiation, the difference between the maximum and minimum values of chromosomal aberration "Dicentric + ring/100 Cells" is 2.5 times that of the former. Two hours after the first day of radiotherapy, the detection rate of chromosomal aberrations significantly increases. Under the same treatment dose, when the dose rate increases by 33 times, the ratio of "double centromeres + circular chromosome" / 100 cells increases by 1 times.

Conclusion: The "dicentric+translocation" chromosome can be used as a nonspecific early screening index for cancer. Individual differences in sensitivity to radiation may explain the mechanism of drug resistance. In terms of the radiation damage effect, the radiation dose plays a leading role, and the radiation dose rate plays a secondary role. The maximum dose rate of FLASH radiotherapy should be limited according to the degree of radiation damage.

Gang Liu, Led the monitoring project for occupational radiation diseases in Gansu Province, conducted research on radiation epidemiology, and estimated radiation biological doses and applied biomarkers.Led the monitoring project for occupational radiation diseases in Gansu Province, conducted research on radiation epidemiology, and estimated radiation biological doses and applied biomarkers. Participated in the formulation and revision of the national standard "Method Standard for Estimating Biological Dose Based on Chromosome Aberration"; participated in the formulation of the group standard of the Chinese Radiation Protection Institute "Guidelines for the Establishment and Operation of a Biological Dose Laboratory Network"; participated in the national natural infrastructure project "Research on High-Throughput Intelligent Recognition and Assisted Diagnosis Technology for Cell Micronucleus Images". Participated in the formulation and revision of the national standard "Method Standard for Estimating Biological Dose Based on Chromosome Aberration"; participated in the formulation of the group standard of the Chinese Radiation Protection Institute "Guidelines for the Establishment and Operation of a Biological Dose Laboratory Network"; participated in the national natural infrastructure project "Research on High-Throughput Intelligent Recognition and Assisted Diagnosis Technology for Cell Micronuclei Images.