Neurological and Neurosurgical Intensive Care, 4th edition

HYDROXYUREA is a cytotoxic drug which has recently been investigated as a therapeutic agent in a number of malignant conditions, e.g. cancer of the head and neck (Beckloff, 1967), and leukaemia especially chronic myeloid leukaemia (Malpas, 1967; Weil and Tanzer, 1967). It is not a new compound but has only recently been screened for activity against cancer. It is believed that the activity of hydroxyurea is due to an immediate inhibition of DNA synthesis without, apparently, inhibition of RNA or protein synthesis. Yarbro (1965) showed that hydroxyurea prevented the incorporation of 32p into the DNA of ascites tumour cells while having only a slight effect on the incorporation of 32p into RNA. An attempt has been made to determine, by the use of phytohaemagglutininstimulated lymphocyte cultures, the concentration of the drug necessary for cytotoxic and antimitotic activity.