Cytotoxicity of restriction enzyme-induced DNA strand breaks in radiosensitive and radioresistant human tumor cell lines

Journal Article · Mon Sep 20 04:00:00 EDT 1993 · International Journal of Radiation Oncology, Biology and Physics; (United States)

DOI:https://doi.org/10.1016/0360-3016(93)90243-O· OSTI ID:6574091

Kinashi, Y; Nagasawa, H; Little, J B ^[1]

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1. Harvard School of Public Health, Boston, MA (United States)

The purpose was to examine the role of sensitivity to specific types of DNA double strand breaks in human tumor cell response. The X ray-sensitive human squamous carcinoma cell line SCC-61 and the X ray-resistant line SQ-20B were exposed to the restriction enzymes HaeIII, HinfI, PvuII, BamHI by electroporation. Cyotoxicity of these restriction endonucleases was measured by a colony formation assay. Cell killing by each enzyme occurred in a concentration-dependent manner. The radiosensitive cell line was more sensitive to all four restriction enzymes than the radioresistant line, paralleling the response to ionizing radiation. However, the magnitude of the difference was smaller than for radiation. The 5-base sticky ended cutter HinfI and 6-base blunt ended cutter PvuII were much more effective in killing cells from both lines than BamHI, a 6-base sticky ended cutter, whereas the 4-base blunt ended cutter HaeIII was intermediate in its effectiveness. Thus, enzyme sensitivity could not be related to the type of cutter or the distance between cutting sites. 14 refs., 1 fig., 2 tabs.

• OSTI ID: 6574091
• Journal Information: International Journal of Radiation Oncology, Biology and Physics; (United States), Journal Name: International Journal of Radiation Oncology, Biology and Physics; (United States) Vol. 27:2; ISSN 0360-3016; ISSN IOBPD3
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
560120 -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
CARCINOMAS
DISEASES
DNA-ASE
ENDONUCLEASES
ENZYMES
ESTERASES
GENETIC EFFECTS
HYDROLASES
NEOPLASMS
ORGANIC COMPOUNDS
PHOSPHODIESTERASES
PROTEINS
RADIOSENSITIVITY