Abstract
The recent studies of cancer therapies toward drug targeting to tumor cells are reviewed. There are several problems in the approach of drugs to the tumor cells after administration such as the trans-port through normal tissues, the selectivity of tumor tissue, and the permeability through the membrane of the tumor cells. Many biocompatible materials have been attempted to be used to overcome these problems. Microspheres of proteins, lipoidal particles(liposomes and emulsions), and biodegradable artificial polymers are used as carriers to study passive targeting in body, and also membrane active materials in lipoidal substances are used to solve the insensitivity and the tolerance of tumor cells to antitumor drugs. Also the formulation design of drug using poly(lactic acid)microspheres is presented for the example of lymph targeting and controlled release to prevent tumor metastasis.
