Radiosensitizing agents

Sulphide and sulphoxide complexes have been extensively studied since cis-RuC12(DMSO)4 (DMSO, dimethyl sulphoxide, (Me)2SO) was found to have anti-tumour properties and to be a precessor for radiosensitizing agents. Such complexes can act as catalysts for the oxidation of sulphides with molecular oxygen. 

Sarkaria JN, Busby EC, Tibbetts RS, Roos P, Taya Y, et al. 1999. Inhibition of ATM and ATR kinase activities by the radiosensitizing agent, caffeine. Cancer Res. 59 4375-82... 

Radiosensitizing Agents - Agents which sensitize tumor cells to the lethal effects of ionizing radiation are being actively pursued. Two known radiosensitizers, metronidazole and nitrofurazone, were shown to be cytotoxic to Chinese hamster cells in the absence of radiation, but only under hypoxic conditions.82 The x-ray requirement for antitumor activity in a murine anaplastic carcinoma was reduced when metronidazole was administered orally before irradiation.83 RO-07-0582 (13), a compound... 

Effective tumor control can be achieved by the use of substances that can increase the sensitivity of the tumor cells for chemotherapeutic agents and therefore reduce the side effects for the normal cells. Withaferin A (2), the major constituent of the Withania somnifera, was found to be a potent radiosensitizing agent when administered before radiotherapy. The effect was studied on B16F1 melanoma and fibrosarcoma mouse tumors grown in C57BL and Swiss albino mice, respectively. The study concluded that the radiotherapy response of both tumors increased substantially on administration of withaferin A (2) [87]. 

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