Synthesis and characterization of theranostic poly(HPMA)-c(RGDyK)-DOTA-64Cu copolymer targeting tumor angiogenesis: tumor localization visualized by positron emission tomography.

Poly(HPMA)-c(RGDyK)-DOTA-64Cu copolymers were synthesized and characterized for tumor localization in vivo as a theranostic scaffold for cancer imaging and anticancer drug delivery targeting tumor angiogenesis. Tumor localization of the poly(HPMA)-c(RGDyK)-DOTA-64Cu copolymers was visualized in mice bearing human prostate cancer xenografts by positron emission tomography (PET) using a microPET scanner. PET quantitative analysis demonstrated that tumor 64Cu radioactivity (2.75 ± 0.34 %ID/g) in tumor-bearing mice 3 hours following intravenous injection of the poly(HPMA)-c(RGDyK)-DOTA-64Cu copolymers was significantly higher than the tumor 64Cu radioactivity (1.29 ± 0.26 %ID/g) in tumor-bearing mice injected with the nontargeted poly(HPMA)-DOTA-64Cu copolymers (p = .004). The poly(HPMA)-c(RGDyK)-DOTA-64Cu copolymers hold potential as a theranostic scaffold for cancer imaging and radiochemotherapy of prostate cancer targeting tumor angiogenesis by noninvasive tracking with PET.

Synthesis of Poly[APMA]-DOTA-64Cu conjugates for interventional radionuclide therapy of prostate cancer: assessment of intratumoral retention by micro-positron emission tomography.

To develop new radiopharmaceuticals for interventional radionuclide therapy of locally recurrent prostate cancer, poly[N-(3-aminopropyl)methacrylamide] [poly(APMA)] polymers were synthesized by free radical precipitation polymerization in acetone-dimethylsulfoxide using N,N'-azobis(isobutyronitrile) as the initiator. The polymers were characterized with nuclear magnetic resonance, size exclusion chromatography, and dynamic light scattering (M(n) = 2.40 x 10(4), M(w)/M(n) = 1.87). Subsequently, poly[APMA] was coupled with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as an activator, followed by conjugation with (64)Cu radionuclide. Prolonged retention of poly[APMA]-DOTA-(64)Cu conjugates within the tumor tissues was demonstrated by micro-positron emission tomography at 24 hours following intra-tumoral injection of the conjugates to human prostate xenografts in mice. The data suggest that the poly[APMA]-DOTA-(64)Cu conjugates might be useful for interventional radionuclide therapy of locally recurrent prostate cancer in humans.