Pharmacokinetic and therapeutic outcome in melanoma cells, of the administration of symmetric and asymmetric cationic photosensitizers

The response of melanoma cell lines to a range of novel cationic photosensitizers based on either a protoporphyrin or a mesotetra(4-carboxylphenyl)porphine molecule, has been examined. The drugs varied in terms of either their symmetry or their side chain configuration. The effect of these variables on drug uptake and photodynamic cell kill were tested. The absorption wavelengths for the drugs were measured and a shift to the red was seen in the presence of cells. Drug uptake was measured and the cationic sensitizers had a relatively high uptake when compared to anionic HpD. The efficiency of the drugs in causing cell kill was expressed in terms of clonogenic cell survival, The asymmetric photosensitizers were more efficient in destroying mouse and human melanoma cells than the clinically used anionic HpD, which was in turn more efficient than the symmetric sensitizers tested.