Novel Topical Photodynamic Therapy of Prostate Carcinoma Using Hydroxy-aluminum Phthalocyanine Entrapped in Liposomes
Abstract
Background: Clinically approved anticancer photodynamic therapy (PDT) is now heavily studied for various cancer diagnoses. We focused on the treatment efficacy of topical administration of hydroxy-aluminum phthalocyanine (AlOH-PC) entrapped in liposomes against in vivo models of prostate carcinomas.
Materials and Methods: LNCaP and PC3 cells were subcutaneously injected into the right flank of athymic nude mice. Mice with grown tumours were used for in vivo efficacy studies.
First by, we applied different doses of AlOH-PC to less aggressive LNCaP tumours to determine the efficient dose. In later studies, we focused on more aggressive prostate tumours (PC3) using doses of liposomal-AlOH-PC gel formulation.
Topical application of photosensitizers was followed by PDT irradiation (600-700 nm, 635 nm peak). Tumour growth was measured three times a week.
Results: Comparison of PDT of aggressive PC3 and less aggressive LNCaP prostate carcinomas showed that both tumour types are sensitive and treatable by liposomal formulation of AlOH-PC. For LNCaP tumours the efficient dose (100% experimental animals cured, n=8/8) was 4.5 mg/ml of AlOH-PC in the gel.
Whereas, in the case of PC3 carcinoma, a dose of 4 mg/ml significantly postponed tumour growth, but no animals were cured (n=0/8); a sufficient curative dose (100% mice cured, n=8/8) was 6 mg/ml of AlOH-PC in the gel. Conclusion: Liposomal AlOH-PC gel has potential for efficient PDT of prostate carcinomas.