Apoptosis induced by hematoporphyrin monomethyl ether combined with He-Ne laser irradiation in vitro on canine breast cancer cells.

Department of Veterinary Clinic, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.
The Veterinary Journal (Impact Factor: 2.42). 06/2011; 188(3):325-30. DOI: 10.1016/j.tvjl.2010.05.013
Source: PubMed

ABSTRACT Hematoporphyrin monomethyl ether (HMME) is a novel and promising porphyrin-related photosensitizer for photodynamic therapy (PDT). The aim of this study was to investigate HMME-induced apoptosis in CHMm cells, a canine breast cancer cell line. CHMm cells were treated with HMME and a He-Ne laser at a wavelength of 632.8 nm. Cell viability was determined using the trypan blue exclusion assay. Apoptosis was analyzed using Hoechst 33258, AO/EB, Annexin V/PI staining and single-cell gel electrophoresis (comet assay). Apoptotic morphology was further confirmed by Giemsa staining and transmission electron microscopy. Rates of apoptosis increased following PDT-HMME treatment in a time-dependent manner. Taken together, these results demonstrated that apoptosis plays a major role in PDT-HMME-induced reduction in the viability of CHMm cells.

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