The effect of liposome encapsulated antineoplastic agents on transitional cell carcinoma in tissue culture.

Liposomes are microscopic vesicles composed of one or more phospholipid bilayers separated by an equal number of aqueous interspaces. These "capsules" are formed when dried lipid is combined with excess water, agitated, and warmed above the transition temperature of the lipid (the temperature at which the lipid changes from a gel state to a fluid state). If a chemical in solution is present when the vesicles form, the chemical will be trapped in either the aqueous interspaces (hydrophilic compounds), or the lipid bilayer (hydrophobic compounds). The urinary bladder is an attractive site for the topical application of liposome encapsulated compounds due to its accessibility and since the introduction of various agents, including antineoplastic compounds, into the bladder is a well established treatment option. Utilization of liposome technology may provide the means for a more effective intravesical treatment of transitional cell carcinoma.