Determination of the maximal tumor/normal skin ratio after HpD or m-THPC administration in hairless mouse (SKh-1) by fluorescence spectroscopy--a non-invasive method.
Two major steps in our study on the treatment of skin tumors by photochemotherapy (PCT) were the development of a skin tumor model in hairless mice by chemical carcinogenesis and by the use fluorescence spectroscopy, a semi-quantitative and non-invasive method, to determine the time after i.p. injection of photosensitizer when the tumor/normal skin ratio is the highest. Carcinogenesis provided mice bearing many benign papillomas and these were used to determine the tumor/normal skin ratios of two photosensitizers by fluorescence spectroscopy. Hematoporphyrin derivative (HpD) (5 mg/kg body weight) and m-tetra(hydroxyphenyl)-chlorin (m-THPC) (0.3 mg/kg body weight) were injected, and fluorescence measured at 4, 8, 24, 48, 72 and 96 h after injection. The tumor/normal skin ratio was 6.2 for HpD and 5.1 for m-THPC. The times required to reach these ratios were 48 h for HpD and 72 h for m-THPC. Published reports indicate that m-THPC gives a much higher tumor/normal skin ratio than HpD. These results must be confirmed by organic extraction. Photodynamic therapy with the same doses of HpD and m-THPC used in this pharmacokinetic study must also be carried out to compare the toxicities of the two photosensitizers and to determine which is best for this type of tumor.
Bossu
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Laboratoire d'Hématologie, Physiologie et Biologie Cellulaire, Faculté des Sciences Pharmaceutiques et Biologiques, Université Henri Poincaré-Nancy I, France.
A'Amar
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O
Parache
R M
RM
Notter
D
D
Labrude
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P
Vigneron
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C
Guillemin
F
F
D000818:Animals; D000970:Antineoplastic Agents / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005260:Female; D017324:Hematoporphyrin Derivative / Q000493:pharmacokinetics / Q000627:therapeutic use*; D008652:Mesoporphyrins / Q000493:pharmacokinetics / Q000627:therapeutic use*; D051379:Mice; D008812:Mice, Hairless; D009368:Neoplasm Transplantation; D010212:Papilloma / Q000188:drug therapy* / Q000473:pathology*; D010778:Photochemotherapy; D012867:Skin / Q000473:pathology*; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D013050:Spectrometry, Fluorescence
D000970:Antineoplastic Agents; D008652:Mesoporphyrins; D017324:Hematoporphyrin Derivative; C072269:temoporfin