The effect of porphyrins on normal and transformed mouse cell lines in the presence of visible light

Abstract

Photodynamic therapy consists of the uptake of a photosensitizing dye, often a porphyrin, by tumor tissue and subsequent irradiation of the tumor with visible light of an appropriate wavelength matched to the absorption spectrum of the photosensitizing dye. This class of molecules produces reactive oxygen species when activated by light, resulting in a direct or indirect cytotoxic effect on the target cells. Photodynamic therapy has been used in the treatment of cancer but the technology has a potential for the treatment of several disease conditions mainly because of its selectivity. However, it is not clear why the porphyrins are retained preferentially by abnormal tissue. This paper describes a study of the effect of the association of porphyrin and visible light on two mouse fibroblast cell lines: A31, normal cells and B61, an EJ-ras transformed variant of A31. Two water-soluble porphyrins were used, a positively charged one, tetra(N-methyl-4-pyridyl)porphyrin chloride, and a negatively charged one, tetra(4-sulfonatophenyl)porphyrin-Na salt (TPPS 4 ) in order to assess the effect on cell survival. The results suggest that the B61 cell line is more sensitive to incubation with the anionic porphyrin (TPPS 4 ) followed by light irradiation and that the anionic porphyrin is more efficient in killing the cells than the cationic porphyrin.

Effects of two organotin(IV)(sulfonatophenyl)porphinates on MAPKs and on the growth of A375 human melanoma cells

“…In this study, we show that the three MAPKs, ERK 1/2, JNK and p38, are involved in A375 melanoma cell apoptosis induced by 10 μM (Bu 2 Sn) 2 TPPS or 1 μM (Bu 3 Sn) 4 TPPS, and that FAK does not activate this pathway. We show a rapid cell uptake of the two compounds, including the nucleus and nucleoli, as well as a considerable slowdown of cell growth by using lower concentrations of (Bu 2 Sn) 2 TPPS and (Bu 3 Sn) 4 TPPS at 500 and 80 nM, respectively.…”

“…We show a rapid cell uptake of the two compounds, including the nucleus and nucleoli, as well as a considerable slowdown of cell growth by using lower concentrations of (Bu 2 Sn) 2 TPPS and (Bu 3 Sn) 4 TPPS at 500 and 80 nM, respectively.…”

“…(Bu 2 Sn) 2 TPPS, and (Bu 3 Sn) 4 TPPS were prepared according to previously reported procedures (3) and dissolved as previously reported (6).…”

“…In this context, we regarded a class of porphyrin derivatives as potential anti-tumor drugs for their cytotoxicity and for the property of the porphyrins themselves to be accumulated in large amounts and retained for prolonged periods of time by the malignant lesions as noteworthy (3)(4)(5). We showed that two complexes of the meso-tetra(4-sulfonatophenyl) porphinate (TPPS), (Bu 2 Sn) 2 TPPS and (Bu3Sn)4TPPS, induce the activation of extrinsic and intrinsic apoptotic pathways in melanoma cells (6).…”

“…Concomitant to these studies, we identified concentrations of (Bu 2 Sn) 2 TPPS and (Bu 3 Sn) 4 TPPS which were less toxic but sufficient to affect A375 melanoma cell growth.…”