chloroaluminum-tetrasulfophthalocyanine and phthalocyanine

Aluminum-chloro-tetrasulfonated phthalocyanine (PC) showing an absorption peak at 678 nm was compared to hematoporphyrin derivative (HpD), a photosensitizer commonly used in the photodynamic therapy (PDT) of cancers.. KK-47 cells were exposed to long-wavelength ultraviolet (UVA) or red light (greater than 600 nm, greater than 640 nm and greater than 660 nm) after drug sensitization. With UVA irradiation, a higher photodynamic cell killing effect was observed in the cells treated with HpD than with PC. However, with red light irradiation (both greater than 640 nm and greater than 660 nm) PC resulted in greater cell damage. PC was less toxic to KK-47 cells in the dark. In vivo studies: Using a gold vapor laser (GVL: 627.8 nm, 200 mW/cm2, 200 J/cm2), the photodynamic tumor response was determined in C3H/He mice bearing transplantable squamous cell carcinoma. No significant difference was observed in the tumor volume between the PC and HpD groups, except that the PC group (10.0 mg/kg body weight) showed a significantly higher remission rate (3/6) than the control group (0/10, P less than 0.05). Skin photosensitivity test: Skin photosensitivity was estimated by measuring changes in back skin thickness due to photosensitization. With UVA irradiation, a stronger skin reaction was observed in the HpD group, while with visible light irradiation there was no significant difference between the HpD and PC groups. Based on the superior cell killing effect with red light, reduced toxicity to the cells in the dark and mild skin reaction with UVA, PC may be a more promising photosensitizer for PDT.

Topics: Animals; Carcinoma, Squamous Cell; Cell Survival; Hematoporphyrin Photoradiation; Humans; Indoles; Isoindoles; Lasers; Mice; Mice, Inbred C3H; Organometallic Compounds; Photochemotherapy; Skin; Tumor Cells, Cultured; Urinary Bladder Neoplasms

The effect of anatomical site of tumour growth on selective uptake and retention of chloro-aluminium sulphonated phthalocyanine (ClAlSPc) was determined using the murine colorectal carcinoma (Colo 26). Tumours were established in the liver, spleen, kidney, lung, thoracic cavity and s.c. flank region of syngeneic BALB/c mice and animals received 10 mg/kg ClAlSPc by i.v. injection. Colo 26 growths at s.c., intra-pulmonary, intra-thoracic or intra-renal sites took up and retained greater amounts of ClAlSPc than did adjacent normal tissues. Such selective retention of ClAlSPc by neoplastic tissue was not observed when Colo 26 was grown in the spleen, where tumour and normal tissue took up about the same amounts, or the liver, where normal tissue took up more ClAlSPc than either directly implanted or metastatic tumours. ClAlSPc ratios found in tumour/adjacent tissue may vary for a single tumour growing at different anatomical sites and such variability could have a distinct effect on the efficacy of photodynamic therapy of cancer.

Topics: Animals; Colorectal Neoplasms; Female; Indoles; Isoindoles; Mice; Mice, Inbred BALB C; Organometallic Compounds; Photochemotherapy; Tumor Cells, Cultured