Asymmetrically substituted cationic indole- and fluorene porphyrins inhibit tumor proliferation in small intestinal neuroendocrine tumors and medullary thyroid carcinomas.

In this study we demonstrate anticancer activity of novel fully water soluble cationic porphyrins. The two cationic porphyrins 5,10,15-tris(N-methylpyridinium-4-yl)-20-[1-phenyl-4-(3-N-phenylsulfonylindolyl)]-21H,23H-porphyrin chloride (TMPy(3)PhenIndolprot(1)P-Cl(3)) and 5-{5-[2-(9,9-Dimethyl)fluorenyl]-N-methylpyridinium-3-yl}-10,15,20-tris(N-methyl-pyridinium-4-yl)-21H,23H-porphyrin chloride (TMPy(3)PyFluorenyl(1)P-Cl(4)) were prepared and their antiproliferative effects were studied in two human tumor cell lines and a normal human fibroblast cell line. Effects of the novel porphyrin compounds were evaluated in the small intestinal neuroendocrine tumor cell line KRJ-I, the medullary thyroid carcinoma cell line MTC-SK and the normal human fibroblast cell line HF-SAR by cell counting, cell proliferation assays and cell cytotoxicity analyses. TMPy(3)PhenIndolprot(1)P-Cl(3) and TMPy(3)PyFluorenyl(1)P-Cl(4) showed antiproliferative effects in the tumor cell lines MTC-SK and KRJ-I; cell viability was decreased and cytotoxic effects were quantified, while no significant alterations of the human fibroblasts were noted. With the advantage of full water solubility and antiproliferative effects in tumor cell lines, the novel porphyrin compounds TMPy(3)PhenIndolprot(1)P-Cl(3) and TMPy(3)PyFluorenyl(1)P-Cl(4) could be a new therapeutic option in anticancer treatment.

DNA interactions and photocatalytic strand cleavage by artificial nucleases based on water-soluble gold(III) porphyrins.

The novel gold porphyrin complex (5,10,15-tris(N-methylpyridinium-4-yl)-20-(1-pyrenyl)-porphyrinato)gold(III) chloride, [Au(III)(TMPy3Pyr1P)]Cl4, was prepared and characterized by optical spectroscopy, high-resolution nuclear magnetic resonance (NMR), and electrospray mass spectrometry. This cationic multichromophore compound exhibits excellent water solubility and does not form aggregates under physiological conditions. Binding interactions of this complex and related model compounds with nucleic acid substrates have been studied and characterized by NMR and circular dichroism spectroscopy. The photoreactivity of [Au(III)(TMPy3Pyr1P)]Cl4 was investigated under anaerobic and aerobic conditions in the presence of an excess of purine nucleoside, guanosine, and plasmid DNA. Photocatalytic oxidative degradation of guanosine and the change from supercoiled to circular plasmid DNA upon monochromatic irradiation and polychromatic blue-light exposure with a maximum at 420 nm was explored. The potential of the novel water-soluble cationic metallointercalator complex [Au(III)(TMPy3Pyr1P)]Cl4 to serve as a catalytic photonuclease for the cleavage of DNA has been demonstrated.