Correlation of photodynamic activity and fluorescence signaling for free and pegylated mTHPC in mesothelioma xenografts.
OBJECTIVE
Correlation of photodynamic activity (PDT) and fluorescence signaling for free and pegylated meta-tetrahydroxyphenylchlorin (mTHPC) in nude mice with mesothelioma xenografts.


METHODS
Twelve animals received light delivery (20 J/cm(2), 150 mW/cm(2), spot size 1.2 cm) on the tumor and the hind leg 3 days after sensitization with 0.15 mg/kg free mTHPC (n = 6) or equimolar-dosed pegylated mTHPC (n = 6). Groups of three animals each were sensitized with 0.15 and 0.5 mg/kg free mTHPC or equimolar dosed pegylated mTHPC followed after 3 days by fluorescence microscopy measurements.


RESULTS
Pegylated mTHPC resulted in a similar extent of PDT-related tumor necrosis but in lower skin phototoxicity than free mTHPC. Both mTHPC formulations were heterogeneously distributed in the tumor and were mainly localized in perivascular areas. Pegylated mTHPC revealed a higher tumor to skin fluorescence intensity ratio than free mTHPC (P<0.001).


CONCLUSIONS
Fluorescence signaling measurement has the potential to predict the photodynamic activity for both mTHPC formulations in mesothelioma xenografts.
Tran
Nam
N
Division of Thoracic Surgery, University of Lausanne, Lausanne, Switzerland.
Krueger
Thorsten
T
Pan
Youmin
Y
Yan
Hua
H
Cheng
Cai
C
Altermatt
Hans-Jörg
HJ
Ballini
Jean-Pierre
JP
Borle
François
F
Ris
Hans-Beat
HB
Andrejevic-Blant
Snezana
S
D000818:Animals; D005260:Female; D008652:Mesoporphyrins / Q000494:pharmacology*; D008654:Mesothelioma / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009336:Necrosis; D009368:Neoplasm Transplantation; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D010997:Pleural Neoplasms / Q000188:drug therapy* / Q000473:pathology; D014183:Transplantation, Heterologous
D008652:Mesoporphyrins; D017319:Photosensitizing Agents; C072269:temoporfin