In one aspect, the invention includes a composition for treating a tumor in a subject, comprising {HEAD ~ liposomes} composed of a vesicle forming lipid and between {TAIL ~ about 1 20 mole percent} of a vesicle forming lipid derivatized with a hydrophilic polymer 
In one aspect , the invention includes a composition for treating a tumor in a subject , comprising { HEAD ~ liposomes } composed of a vesicle forming lipid and between { TAIL ~ about 1 20 mole percent } of a vesicle forming lipid derivatized with a hydrophilic polymer
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH