Developments with targeted enzymes in cancer therapy

✍ Scribed by Kenneth D Bagshawe; Surinder K Sharma; Philip J Burke; Roger G Melton; Richard J Knox

• Book ID: 104358984
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 48 KB
• Volume: 11
• Category: Article
• ISSN: 0952-7915
• DOI: 10.1016/s0952-7915(99)00004-7

✦ Synopsis

Cancer therapy based on the delivery of enzymes to tumour sites has advanced in several directions since antibodydirected enzyme/prodrug therapy was first described. It has been shown that methoxypolyethylene glycol (MPEG) can be used to deliver enzyme to a variety of solid tumours. MPEG-enzyme conjugates show reduced immunogenicity and may allow repeated treatment with enzymes of bacterial origin. Enzyme delivery to tumours by polymers can be used to convert a low toxicity prodrug to a potent cytotoxic agent. An example of such a prodrug is CB1954, which can be activated by a human enzyme in the presence of a cosubstrate. Tumourlocated enzymes can also be used in conjunction with a combination of antimetabolites and rescue agents. The rescue agent protects normal tissue but is degraded at cancer sites by the enzyme, thus deprotecting the tumour and allowing prolonged antimetabolite action.