[Studies on hormone-polymer composites in urological field--their application in prostatic cancer therapy].
Our studies on the application of hormone-polymer composites in urological field are discussed in this review. We first studied the modes of in vivo and in vitro release of testosterone from vinyl polymer-testosterone composites prepared by radiation-induced polymerization. It was ascertained by our group that in vivo and in vitro release of testosterone from biodegradable copolypeptide -testosterone composites as well as vinyl polymer composites was well controlled. Using this system, we were successful in preparing a testicular prosthesis, which was made of vinyl polymer-testosterone composites and was ascertained to release testosterone constantly for a long period in the dose range of clinical usage. We also applied this sustained release drug delivery system to the method of administration of an LH x RH agonist, which was one of the best therapeutic drugs for androgen dependent prostatic cancer. Sustained release of the LH x RH agonist in the dose range of clinical usage over a period of several months from copolymer-LH x RH agonist composites was confirmed in both male rats and in prostatic cancer patients. Prostatic cancer cells contain a major secretion protein (alpha-protein or estramustine-binding protein) and estramustine has a high affinity for alpha-protein. Therefore, we examined the effect of an estramustine-microsphere containing anticancer drugs, namely, the missile therapy for prostatic cancer. The missile therapy should open the way to specific and selective chemotherapy for prostatic cancer.
D000818:Animals; D001187:Artificial Organs; D003692:Delayed-Action Preparations; D004961:Estramustine / Q000008:administration & dosage; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage; D006801:Humans; D008297:Male; D011108:Polymers; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D011817:Rabbits; D051381:Rats; D013737:Testis; D013739:Testosterone / Q000008:administration & dosage* / Q000378:metabolism
D003692:Delayed-Action Preparations; D011108:Polymers; D007987:Gonadotropin-Releasing Hormone; D004961:Estramustine; D013739:Testosterone