Chromosomal radiosensitivity in two cell lineages derived from clinically radiosensitive cancer patients.
OBJECTIVE
Despite its prominent contribution to cancer cure and palliation, around 1% to 5% of cancer patients suffer serious side effects from radiotherapy. A cardinal goal in the fields of radiobiology and oncology is to predict normal tissue radiosensitivity of a cancer patient before radiotherapy. Higher tumor control rates are likely if radiotherapy individualization could be achieved by applying predictive approaches.


METHODS
Here, we make use of the cytokinesis block micronucleus assay to assess radiosensitivity in cell lines derived from two different cell lineages obtained from clinically radiosensitive patients. We determined the micronucleus frequency after graded doses of ionizing radiation to primary fibroblasts and lymphoblast cell lines derived from 36 highly radiosensitive cancer patients.


RESULTS
Many cell lines, following exposure to ionizing radiation, from patients with severe clinical reactions to radiotherapy showed statistically significantly higher frequencies of micronuclei than those from patients who had normal reactions to radiotherapy. One individual revealed significantly higher micronucleus frequencies in both cell lineages. Interestingly, lymphoblast cell lines from one patient showed micronucleus frequencies similar to ataxia telangiectasia mutated-deficient cells.


CONCLUSIONS
These results indicate that the micronucleus assay may have use for identifying predisposition to clinical radiosensitivity, at least in a subset of patients as a component of a pretreatment radiosensitivity assay for use in the clinic.
Sprung
Carl N
CN
Division of Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia.
Chao
Michael
M
Leong
Trevor
T
McKay
Michael J
MJ
D019070:Cell Lineage; D002869:Chromosome Aberrations; D002877:Chromosomes, Human / Q000528:radiation effects*; D048749:Cytokinesis; D005347:Fibroblasts / Q000528:radiation effects; D006801:Humans; D008214:Lymphocytes / Q000473:pathology / Q000528:radiation effects; D015162:Micronucleus Tests; D009369:Neoplasms / Q000532:radiotherapy*; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D014407:Tumor Cells, Cultured / Q000528:radiation effects