Photoinactivation induced by ZnPcOCH3 of carcinoma cell (Hep-2)

YSLAS, E. INÉS, DURANTINI EDGARDO N. Y RIVAROLA VIVIANA.

RÍO CUARTO

Jornada; SEMINARIO ACADÉMICO 2003; 2003

UNRC

Photodynamic therapy is an alternative therapy for treatment of solid and superficial tumours and are being investigated for the treatment of atherosclerosis, restenosis, and psoriasis. This therapy is based on the administration of a photosensitizer, which is selective retained by neoplasic tissues, and then subsequently activated with visible light of an apropiate wavelenght. This new therapy result in a sequence of photochemical and photobiologic processes that cause irreversible photodamage to neoplasic tissues. This work describes the photobiologic properties of tetra methoxy Zn II phthalocyanine on larynges carcinoma human cell line (Hep-2). The uptake of ZnPcOCH3 was linearly increasing with time for the first 1-2 hs of incubation and tend to a saturation value after long incubation ³ 3h. Cell toxicology induced by Phthalocyanine was first analized in dark condition and no toxicity in terms of celll survival was detected at 5x10-7 M. In contrast the combination of photosensitizer with visible light induced a decrease in cell survival of 20 %. The morphologic análisis of the cell perfomed with Hoechst-33258 revealed that the cell death after irradiation for 15 min produced chromatine fragmentation, caracteristic of apoptosis. The intracellular localization of ZnPcOCH3 appears to preferntially accumulate in lysosomes, in the perinuclear area.