Antitumor effects of an interferon-loaded silicone formulation in human renal cell carcinoma in nude mice.
Conventional therapy for renal cell carcinoma using interferon (IFN) has shown limited antitumor action. The IFN-loaded silicone formulation (IFN-SF) is a sustained-release formulation of human lymphoblastoid IFN, with a medical grade silicone elastomer used as the carrier material. We evaluated the antitumor effect of IFN-SF on human renal cell carcinoma cell line (KU-2) transplanted to nude mice. The treatment was started when the tumor nodules had grown 6 to 8 mm in diameter. IFN-SF, on an aqueous solution of IFN, was given by subcutaneous or peritumoral injection. Antitumor effects were evaluated according to tumor weights calculated as (long diameter) x (short diameter)2/2 in 7 groups consisting of 6 mice each. Serum IFN levels remained detectable up to 30 days after subcutaneous injection of IFN-SF. IFN-SF administered by the subcutaneous and peritumor route significantly inhibited growth of the tumor when compared with tumor growth in the untreated mice and mice treated with aqueous IFN solution. IFN-SF had equivalent inhibitory effects on tumor growth by peritumor and subcutaneous injection. Results indicated that the use of IFN-SF could reduce the frequency of injections and provide better treatment of patients with renal cell carcinoma because of its long-acting effect when it is used systemically.
Marumo
K
K
Department of Urology, School of Medicine, Keio University, Tokyo, Japan. t0621888@pmail.tepco.co.jp
Huang
Y
Y
Murai
M
M
D000818:Animals; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003692:Delayed-Action Preparations; D006801:Humans; D016898:Interferon-alpha / Q000008:administration & dosage* / Q000493:pharmacokinetics; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008819:Mice, Nude; D012828:Silicones
D003692:Delayed-Action Preparations; D016898:Interferon-alpha; D012828:Silicones