Translator Disclaimer
1 December 2004 An Evaluation of Exogenous Application of Protoporphyrin IX and its Dimethyl Ester as a Photodynamic Diagnostic Agent in Poorly Differentiated Human Nasopharyngeal Carcinoma
Author Affiliations +
Abstract

5-Aminolevulinic acid and its esterified analogues have been under much investigation to enhance the endogenous production of protoporphyrin IX (PpIX) in tumor cells. However, in this work, we studied the in vitro and in vivo efficacy of exogenously administered PpIX and its esterified analogue, PpIX dimethyl ester (PME), in poorly differentiated human nasopharyngeal carcinoma (NPC/CNE-2) as a photodynamic diagnostic (PDD) agent. NPC/CNE-2 at its earliest time, 1 h after incubation with PME in in vitro studies, has exhibited 64% (P < 0.01) higher tumor to normal cell (T/N) fluorescence ratio than with PpIX. In an in vivo mouse xenograft model, comparable photosensitizer concentration in tumor after intravenous administration was observed at 1–3 h time points, but at 9 h, PME had 31% (P = 0.05) greater concentration in tumor compared with PpIX. In addition, by constituting PME and PpIX in different topical gel composites, of which, PME gel composition of 8:2 Plasdone® and Gantrez® resulted in the highest T/N ratio at 6 h after application (34%; P < 0.05) in comparison with other gel composites. Evaluation of PME and PpIX constituted in the delivery vehicles investigated showed comparable selectivity for tumor at 1–3 h, thus neither photosensitizer is more efficient than the other for PDD at the early time points; however, beyond 6 h, PME had higher selectivity for tumor compared with PpIX. Thus, further investigation is warranted to improve the drug delivery vehicle for greater tumor selectivity at a shorter incubation time.

Vanaja Tammilmani, Karen Kar Lye Yee, Paul Wan Sia Heng, Khee Chee Soo, and Malini Olivo "An Evaluation of Exogenous Application of Protoporphyrin IX and its Dimethyl Ester as a Photodynamic Diagnostic Agent in Poorly Differentiated Human Nasopharyngeal Carcinoma," Photochemistry and Photobiology 80(3), 596-601, (1 December 2004). https://doi.org/10.1562/0031-8655(2004)080<0596:AEOEAO>2.0.CO;2
Received: 6 May 2004; Accepted: 1 August 2004; Published: 1 December 2004
JOURNAL ARTICLE
6 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top