Enhanced therapeutic effect on murine melanoma and angiosarcoma cells by boron neutron capture therapy using a...

We have already achieved successful treatment of several human patients with malignant melanoma by boron neutron capture therapy (BNCT) using 10B1-paraboronophenylalanine (10B1-BPA). In this communication we used a new compound, a manganese boronated protoporphyrin (Mn-10BOPP), and compared it to 10B1-BPA.HCl with respect to uptake in murine melanoma and angiosarcoma cells as well as to their respective cell killing effects using BNCT. Mn-10BOPP was found to be 3 to 10 times more effectively taken up by melanoma cells and angiosarcoma cells than 10B1-BPA.HCl when the content of 10B was measured by the new method, inductively coupled plasma-mass spectrometry (ICP-MS). In addition, melanoma cells and angiosarcoma cells preincubated with Mn-10BOPP were 15 to 20 times more efficiently killed by BNCT than cells preincubated with 10B1-BPA.HCl. These results suggest that Mn-10BOPP is a suitable compound for BNCT of not only malignant melanoma but also angiosarcoma.