Photodynamic effect of isosteric water-soluble phthalocyanines on human nasopharynx KB carcinoma cells

JOSEFINA AWRUCH; MARÍA C. GARCÍA VIOR; JULIETA MARINO; LELIA E. DICELIO; LEONOR P. ROGUIN

New Mexico

Congreso; 6th International Conference on Porphyrins and Phthalocyanines; 2010

Society of Porphyrins and Phthalocyanines

Phthalocyanines have been found to have applications as phototoxic drugs for PDT1-5. In addition to their well-known chemical stability, phthalocyanines possess characteristic absorption spectra6, with a Soret band at approximately 350 nm and a usually narrow but very strong Q-band around 675 nm, with a molar absorption coefficient in the range of 105 M-1 cm-1.The photodynamic activity of water-soluble cationic zinc(II) phthalocyanines using human nasopharynx carcinoma (KB cells) was investigated. A sulfur-linked cationic dye, named: 2,9(10),16(17),23(24)-tetrakis[(2-trimethylammonium)ethylsulfanyl]phthalocyaninatozinc(II) tetraioidide (TAES) is the most active of four sensitizer assays and shows a singlet oxygen quantum yield of 0.58 and a higher bathochromic shift of 10 nm for the Q-band as compared with the oxygen-linked cationic aliphatic phthalocyanine:  2,9(10),16(17),23(24)-tetrakis[(2-trimethylammonium)ethoxy]phthalocyaninatozinc(II) tetraioidide and the best photo-stability in water in comparison with their tetra--substituted counterparts 1,8(11),15(18),22(25)-tetrakis[(2-trimethylammonium)ethoxy]phthalocyaninatozinc(II) tetraioidide and 1,8(11),15(18),22(25)-tetrakis[(2-trimethylammonium)ethylsulfanyl]phthalocyaninatozinc(II) tetraioidide. Phthalocyanine TAES, partially localized in lysosomes, led to cell photoinactivation in a concentration- and light dose-dependent manner. After photodynamic treatment, TAES induced an apoptotic response - as indicated by morphological cell changes - an increase in the activity of caspase-3 and the cleavage of Poly-ADP-Ribose-Polymerase substrate (PARP). Necrotic cells accounted for less than 10% of total cell population.REFERENCES 1.R. K. Pandey, J. Porphyrins Phthalocyanines 4, 2000, 368-373.2.H. Ali, J. E. Van Lier, Chem. Rev. 99, 1999, 2379-2450.3.M. G. H. Vicente, Curr. Med. Che., Anti-Cancer Agents 1, 2001, 175-194.4.I. J. MacDonald, T. J. Dougherty, J. Porphyrins Phthalocyanines 5, 2001, 105-129.5.M. R. Detty, S. L. Gibson, S. J. Wagner, J. Med. Chem. 47, 2004, 3897-3915.6.C. C. Leznoff, A. B. P. Lever, editors.  Phthalocyanines. Properties and applications, vols. 1-4. New York:  VCH; 1989, 1992, 1993, 1996.