Tumor-localizing and Photosensitizing Properties of the Main Components of Hematoporphyrin Derivative

Both 3H-labeled and unlabeled hematoporphyrin derivative (HPD) were analyzed by high-pressure liquid chromatography (HPLC) and gel permeation chromatography. Four main components were isolated by HPLC, and two were isolated by gel permeation chromatography. The tumor-localizing ability of each component was tested and compared to that of 67Ga and 3H2O by injection in mice bearing Lewis lung carcinoma. The photosensitizing abilities of the HPLC-separated components in vitro were also tested. Finally, porphyrin extracts of tumors from mice given HPD were analyzed by HPLC. The tumor-localizing ability of the components increased with decreasing polarity. While crude HPD localized in tumor tissue only to the same extent as did 3H2O, Component 7 was almost as effective as was 67Ga in localizing in the tumor. The cellular uptake of HPD components increased with decreasing polarity. In accordance with this, the low-polarity components were the most effective photosensitizers.