Multiple fractions of gamma rays induced resistance to cis-dichloro-diammineplatinum (II) and methotrexate in human HeLa cells

Journal Article · Thu Jun 01 00:00:00 EDT 1989 · International Journal of Radiation Oncology, Biology and Physics; (USA)

DOI:https://doi.org/10.1016/0360-3016(89)90959-0· OSTI ID:5560960

Osmak, M; Perovic, S ^[1]

---

1. Ruder Boskovic Institute, Croatia (Yugoslavia)

Previous irradiation could induce changes in the cell-sensitivity to additional cytotoxic agents. In this study we examined whether the sensitivity to additional cytotoxic agents was affected in cells irradiated with multiple fractions of gamma rays if these agents were given at the time when the lesions induced in DNA by radiation have already been repaired. Human cervix carcinoma HeLa cells were irradiated daily with 0.5 Gy of gamma rays five times a week for 6 weeks. When the fractionation regimen was completed, that is when the cells had accumulated the total dose of 15 Gy of gamma rays, the sensitivity of these cells to gamma rays, UV light, cis-dichlorodiammineplatinum (II) (cis-DDP), methotrexate (MTX), and hydroxyurea (HU) was examined and compared to control cells. Results revealed that preirradiated cells did not change sensitivity to gamma rays and UV light, but that they increased the resistance to cis-DDP, and MTX (especially for higher concentrations of MTX), and increased sensitivity to HU (for lower concentrations of HU). The increased resistance to cis-DDP was also measurable up to 30 days after the last dose of gamma rays. The results indicate that preirradiation of HeLa cells with multiple fractions of gamma rays could change their sensitivity to additional cytotoxic agents, and that this is a relatively long-lasting effect. Our results suggest that caution is needed in medical application of radiation combined with chemical treatment.

• OSTI ID: 5560960
• Journal Information: International Journal of Radiation Oncology, Biology and Physics; (USA), Vol. 16:6; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANTINEOPLASTIC DRUGS
BIOLOGICAL EFFECTS
HELA CELLS
BIOLOGICAL RADIATION EFFECTS
SENSITIVITY
HYDROXYUREA
METHOTREXATE
CARCINOMAS
DNA REPAIR
FRACTIONATED IRRADIATION
GAMMA RADIATION
MAN
RADIATION DOSES
RADIOSENSITIVITY
ULTRAVIOLET RADIATION
UTERUS
AMIDES
ANIMALS
ANTIMETABOLITES
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BODY
DISEASES
DOSES
DRUGS
ELECTROMAGNETIC RADIATION
FEMALE GENITALS
HYDROXY COMPOUNDS
IONIZING RADIATIONS
IRRADIATION
MAMMALS
NEOPLASMS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PRIMATES
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
VERTEBRATES
560120* - Radiation Effects on Biochemicals
Cells
& Tissue Culture