Treatment of a syngeneic rat tumor with magnetically responsive albumin microspheres labeled with doxorubicin or protein A

• Published in: Gynecologic oncology Vol. 27; no. 1; pp. 34 - 43
• Main Authors: Rettenmaier, Mark A., Stratton, Joan A., Berman, Michael L., Senyei, Andrew, Widder, Kenneth, White, Donald B., DiSaia, Philip J.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.05.1987; Elsevier
• Subjects: Adenocarcinoma - drug therapy; Albumins - administration & dosage; Animals; Antineoplastic agents; Biological and medical sciences; Chemotherapy; Doxorubicin - administration & dosage; Mammary Neoplasms, Experimental - drug therapy; Medical sciences; Microspheres; Neoplasm Metastasis; Neoplasm Transplantation; Pharmacology. Drug treatments; Rats; Rats, Inbred F344; Staphylococcal Protein A - administration & dosage; Antineoplastic agent; Animal model; Microsphere; Rat; Transportation system; Rodentia; Vertebrata; Chemotherapy; Mammalia; Magnetic; Treatment; Tumor; Anthracyclins; Mammary gland; Experimental tumor; Drug delivery system
• ISSN: 0090-8258; 1095-6859
• DOI: 10.1016/0090-8258(87)90228-9

The tumoricidal activity of magnetically responsive albumin microspheres tagged with either doxorubicin or Staphylococcal protein A was tested against an induced mammary adenocarcinoma, 13762, implanted subcutaneously in the tail of female Fischer-344 rats. Magnetically responsive albumin microspheres containing Fe3O4 particles were prepared by an emulsion polymerization method incorporating either doxorubicin or protein A into the albumin matrix. Microspheres were produced with an average diameter of 1 μm (0.2 to 1.5 μm) in a concentration of 109 microspheres/mg. Microspheres were injected either directly into the tail artery and localized to the implanted tumor using a permanent bipolar adjustable gap magnet with a field strength of 8000 Oe, or directly into the femoral vein with no magnetic localization. Control groups consisted of animals treated with intravenously or intraarterially administered microspheres containing no active agent, and a no-treatment group. Survival was significantly greater in both the doxorubicin- and protein A-treated animals than in the control groups. First appearance of local metastases was prolonged in only the intraarterial magnetically localized doxorubicin-treated group of animals. Tumor growth rate was significantly depressed in both intraarterially magnetically localized treatment groups when compared to intravenously administered nonlocalized treatment groups. Magnetically responsive albumin microspheres appear to be an effective delivery system for cytotoxic agents and biologic response modifiers. Significant tumoricidal activity can be produced with a one-time administration of these agents utilizing this drug delivery system.