Development of a new tumor seeking compound for neutron capture therapy

结果1.体内硼浓度研究显示，静脉注射0.05mmol/kg剂量后24 h，STA-BX 909的肿瘤硼浓度最高，其次是STA-BX 900和STA-BX 910。这种趋势与肝脏硼浓度有关。2.体外硼浓度分析：在培养的9 L胶质肉瘤细胞系中，加入BSH的条件培养基中，硼浓度在24 h后仍保持稳定。STA-BX 909显示硼浓度随时间增加。在BSH中，细胞内硼浓度可能取决于培养基硼浓度。STA-BX 909在肿瘤细胞中进行性蓄积，硼浓度的增加表明肿瘤细胞对硼的主动摄取机制。3.中子照射后，STA-BX 909的生物学效应强于BSH，而不含硼化合物的中子照射的生物学效应最小。进一步的基础研究是必要的，以开发一种临床适用的药物。

Three types of boronated manganese metalloporphyrin (STA-BX900, STA-BX909, STABX910) for neutron capture therapy has been developed.Results1.In vivo boron concentration study revealed highest tumor boron concentration in STA-BX909 followed by STA-BX900 and STA-BX910 24 hours after intravenous injection of 0.05mmol/kg dose. This tendency was correlated with the liver boron concentration. From this result, STA-BX909 was chosen for further radiobiological study.2.In vitro boron concentration analysis : In the cultured 9L gliosarcoma cell line, the boron concentration was stable with BSH added condition medium even after 24 hours. STA-BX909 showed increase in boron concentration as a function of time. In BSH,the intracellular boron concentration may be dependent on the medium boron concentration. STA-BX909 progressively accumulated in tumor cells and the increase of boron concentration indicated an active uptake mechanism.3.Neutron irradiation revealed also stronger biological effect with STA-BX909 than BSH and least with neutron irradiation without boron compound.As conclusions, boronated metalloporphyrin is a potential boron carrier for boron neutron capture therpay for malignant brain tumors. Further basic research is warranted to develop a clinically applicable drug.