A fundamental study of radiosensitizers for application in clinical radiotherapy *
Basic studies regarding four drugs ; acyclovir, indomethacin , allopurinol and riboflavin, for which the radiosensitivity effects are reported, were carried out from the aspects of (1) the radiosensitivity effect on experimental tumors and (2) any or no increase in damage to normal tissues, particularly bone marrow damage and skin reaction . In an experiment with a Greene's melanoma transplanted into Syrian golden hamsters, of the four above-mentioned drugs, indomethacin showed a significant sensitivity effect (10Ｇｙ irradiated group ｐ＜0.05) in comparison with a controlled case. For the Greene's melanoma, administration of indomethacin about 30 minutes before irradiation increased the radiation effect. For normal tissues (bone marrow), no significant difference in the sensitivity effect could be observed. For normal tissues in terms of skin reaction, no significant difference was seen in a 15Ｇｙ irradiated group (ｐ＝0.67), but a significant difference was observed in a lOＧｙ irradiated group (ｐ＜0,05). However, the skin reaction (reddening) was slight. Indomethacin is already being used as an anti-inflammatory drug in clinical practice. Its radiosensitivity potential on tumors is believed to take effect when combined with radiotherapy, (Accepted on September 5 . 1997) Kawasaki Igakkaishi 23(2) 99-112, 1997
