Photodynamic Therapy with the Silicon Phthalocyanine Pc 4 Induces Apoptosis in Mycosis Fungoides and Sezary Syndrome

This is the authors' abstract. We don't add key points for this paper.

Our current focus on the effects of Photodynamic Therapy (PDT) using silicon phthalocyanine Pc 4 photosensitizer on malignant T lymphocytes arose due to preclinical observations that Jurkat cells, common surrogate for human T cell lymphoma, were more sensitive to Pc 4-PDT-induced killing than epidermoid carcinoma A431 cells. Mycosis fungoides (MF) as well as Sezary syndrome (SS) are variants of cutaneous T-cell lymphoma (CTCL) in which malignant T-cells invade the epidermis. In this study, we investigated the cytotoxicity of Pc 4-PDT in peripheral blood cells obtained from patients with SS and in skin biopsies of patients with MF. Our data suggest that Pc 4-PDT preferentially induces apoptosis of CD4(+)CD7(-) malignant T-lymphocytes in the blood relative to CD11b(+) monocytes and nonmalignant T-cells. In vivo Pc 4-PDT of MF skin also photodamages the antiapoptotic protein Bcl-2.