Immobilized adriamycin: a tool for separating cell surface from intracellular mechanisms.

Pharmacologic agents may exert their biological activity at the level of the cell membrane. Of particular interest is the anticancer agent adriamycin. This drug has previously been considered to act by intercalation with nuclear DNA, but recent evidence suggests the possibility that the cell surface membrane may represent an alternative target. To test this hypothesis, adriamycin was attached to insoluble supports, and conditions suggesting that the drug was actively cytotoxic without entering cells were demonstrated.