The in vitro PDT efficacy of a novel metallophthalocyanine (MPc) derivative and established 5-ALA photosensitizing dyes against human metastatic melanoma cells

Abstract

Background and objective: Numerous worldwide clinical trials have shown that photodynamic therapy (PDT) represents an effective and safe modality for various skin disorders, but little research has been done in terms of its effect on malignant melanomas (MM). Thus, the aim of this study was to compare the effect of both established porphyrin photosensitizer 5-aminolevulinic acid (5-ALA) and novel metallophthalocyanine (MPc) photosensitizer on human metastatic skin cells which produce a MM.

Materials and methods: The cellular responses following PDT were assessed using changes in cell morphology, cell viability, cytotoxicity, apoptosis, and proliferation.

Results: Findings reported that in vitro human MM cell line A375 (EACC no: 88113005) are highly sensitive to growth inhibition and apoptosis induction by the cytotoxic side-effects induced by MPc and 5-ALA photosensitizing treatments post-laser irradiation at 680 and 636 nm, respectively. The decrease of cell viability accompanied by an increased cytotoxicity and apoptotic and necrotic levels, with a time-dependant decrease in cellular proliferation was found to be far more significant for MPc-treated cells than 5-ALA-treated cells, since MPc was applied in far lower concentrations and exhibited far less photoxicity to control cells.

Conclusion: Hence, novel MPc proved to be the better photosensitizing dye for metastatic melanoma tumor destruction in combination with laser irradiation and is a particularly attractive photosensitizer since it exhibits so many ideal properties of a photosensitizing agent, thus further research of this possible anticancer agent could contribute to its potential application in PDT cancer treatment of MMs.