Anticancer activities of a metal-free phthalocyanine on MCF-7 and MDA-MB-231 cells and singlet oxygen production as a photosensitizer in PDT

Abstract

Cancer, which is often described as an uncontrollable rapid proliferation of cells, is currently the leading cause of death in the world together with cardiac disease. Therefore, the main purpose of the current research work was to study the anticancer effects of a first-time-synthesized phthalocyanine (Pc) as photosensitizer in PDT against cancer and evaluate its effects on human cells in vitro. Quantum yields of singlet oxygen photogeneration were in air using the relative method with standard-ZnPc as reference and DPBF as chemical quencher for singlet oxygen. The concentration of DPBF was prepared almost 3 x 10-5 molar to avoid chain reactions induced by DPBF in the presence of singlet oxygen. Solutions of Pc as sensitizer (absorbance = 2.0 at the irradiation wavelength) containing DPBF were prepared in the dark and irradiated in the Q band region using the setup described. DPBF degradation at 417 nm was monitored with UV-Vis spectrophotometry. For in vitro studies, nine different MFPc-1 concentrations (0.2 µM- 0.4 µM- 0.8 µM- 1.6 µM- 3.2 µM- 6.4 µM- 12.8 µM- 25.6 µM- 51.2 µM) applied to MCF-7 and MDA-MB-231 breast cancer cell lines for 24 hours and MTT assay was carried out. After determination of optimum concentration, mitotic index, and apoptotic index values of cell lines were determined with administration of these concentrations. Singlet oxygen quantum yield (Φ), which is a measure of the efficiency, of MFPc-1 was found 0.50, although MFPc-1 is being metal-free phthalocyanine. For in vitro studies after the application of different concentrations to MCF-7 and MDA-MB-231 for 24 hours, the optimum concentration was determined as 12 µM for both cell lines by the MTT assay. After application of the determined optimum concentration for 24, 48 and 72 hours, there was a significant decrease in the mitotic index values and significant increase in the apoptotic index values of both MCF-7 and MDA-MB-231 breast cancer cell lines.