Molecular Mechanisms of UVA-Induced Melanoma.

Cutaneous melanoma is a deadly skin cancer, resulting from malignant transformation of melanocytes. Long-wave ultraviolet radiation (315-400 nm) is able to damage DNA, cause mutations, and induce melanoma. However, the exact mechanisms of UVA-induced cutaneous melanoma remain a matter of debate.

Fluorescence photobleaching of ALA and ALA-heptyl ester induced protoporphyrin IX during photodynamic therapy of normal hairless mouse skin: a comparison of two light sources and different illumination schemes.

This study investigated photobleaching of protoporphyrin IX (PpIX) induced by 5-aminolevulinic acid (ALA) and ALA-heptyl ester during superficial photodynamic therapy (PDT) in normal skin of the female BALB/c-nu/nu athymic mouse. We examined the effects of two light sources (laser and broadband lamp) and two different illumination schemes (fractionated light and continuous irradiation) on the kinetics of photobleaching. Our results show that light exposure (0-30 minutes, 10 mW/cm2) of wavelengths of approximately 420 nm (blue light) and 635 nm (red light) induced time-dependent PpIX photobleaching for mouse skin of 2% ALA and ALA-heptyl ester.

A comparison of 5-aminolaevulinic acid- and its heptyl ester: dark cytotoxicity and protoporphyrin IX synthesis in human adenocarcinoma WiDr cells and in athymic nude mice healthy skin.

5-aminolevulinic acid heptyl ester was investigated in human adenocarcinoma WiDr cells and in healthy skin of athymic nude mice in comparison with 5-aminolevulinic acid (ALA). Incubation of WiDr cells with ALA and ALA heptyl ester resulted in production of protoporphyrin IX (PpIX). Concentrations higher than 0.