The PDT activity of free and pegylated pheophorbide a against an amelanotic melanoma transplanted in C57/BL6 mice.
Pheophorbide a (Pba) is a chlorophyll catabolite that has been proposed as photosensitizer in photodynamic therapy. In a previous study we conjugated Pba to monomethoxy-polyethylene glycol (mPEG-Pba), to increase its solubility and pharmacokinetics. Here, we compare the photodynamic therapy efficacy of free Pba and mPEG-Pba to cure a subcutaneous amelanotic melanoma transplanted in C57/BL6 mice. The photosensitizers, i.p. injected (30 mg/kg), showed no toxicity when the animals were kept in the dark. But, after photoactivation with a 660 nm laser (fluence of 193 J/cm(2)), both photosensitizers, in particular mPEG-Pba, showed a strong efficacy to cure the tumor, both in terms of tumor growth delay and increase of Kaplan-Meier median survival time. Together, our in vivo data demonstrate that mPEG-conjugated Pba is a promising photosensitizer for the photodynamic therapy of cancer.
Department of Medical and Biological Sciences, School of Medicine, P.le Kolbe 4, 33100 Udine, Italy.
Valentina
V
Rapozzi
Sonia
S
Zorzet
Marina
M
Zacchigna
Sara
S
Drioli
Luigi E
LE
Xodo
D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002734:Chlorophyll / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D005260:Female; D008027:Light; D018328:Melanoma, Amelanotic / Q000188:drug therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D010778:Photochemotherapy; D011092:Polyethylene Glycols / Q000737:chemistry*; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage* / Q000737:chemistry
D011838:Radiation-Sensitizing Agents; D002734:Chlorophyll; D011092:Polyethylene Glycols; C028210:monomethoxypolyethylene glycol; C032623:pheophorbide a