Ishiwata K, Shiono M, Kubota K, Yoshino K, Hatazawa J, Ido T, Honda C, Ichihashi M, Mishima Y
Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan.
Melanoma Res. 1992 Sep;2(3):171-9. doi: 10.1097/00008390-199209000-00005.
A unique in vivo approach to assessing the concentrations of 4-[10B]borono-L-phenylalanine (L-BPA), a melanoma targeting compound for boron neutron capture therapy (BNCT), was investigated using L-BPA labelled with positron-emitting 18F (half-life = 110 min), i.e., 4-[10B]borono-2-[18F]fluoro-L-phenylalanine (L-[18F]FBPA). High melanoma uptake of L-[18F]FBPA was reduced slightly by competition with L-BPA in the two animal models of the murine B16 melanoma and the melanotic Greene's melanoma No. 179 in hamsters. In mice given L-[18F]FBPA and L-BPA, the concentrations of 10B in B16 estimated from 18F radioactivity were lower than those measured by inductively coupled plasma-atomic emission spectroscopy. Lower estimated values were dependent on the time after injection and on the loading dose of L-BPA. The estimated 10B concentrations for Green's melanomas were comparable to the measured values. Positron emission tomography (PET) using L-[18F]FBPA allowed Greene's melanomas to be clearly visualized. In conclusion, when L-[18F]FBPA is used as a probe for L-BPA in BNCT of malignant melanomas, the melanoma can be localized and the 10B concentrations in tissues can be assessed in vivo using 18F radioactivity by PET.
研究了一种独特的体内方法，用于评估4-[¹⁰B]硼-L-苯丙氨酸（L-BPA）的浓度，L-BPA是一种用于硼中子俘获疗法（BNCT）的黑色素瘤靶向化合物。使用用发射正电子的¹⁸F（半衰期 = 110分钟）标记的L-BPA，即4-[¹⁰B]硼-2-[¹⁸F]氟-L-苯丙氨酸（L-[¹⁸F]FBPA）。在小鼠B16黑色素瘤和仓鼠黑色素性格林179号黑色素瘤这两种动物模型中，L-[¹⁸F]FBPA的高黑色素瘤摄取因与L-BPA竞争而略有降低。在给予L-[¹⁸F]FBPA和L-BPA的小鼠中，根据¹⁸F放射性估计的B16中¹⁰B的浓度低于通过电感耦合等离子体原子发射光谱法测量的浓度。较低的估计值取决于注射后的时间和L-BPA的负荷剂量。格林黑色素瘤的估计¹⁰B浓度与测量值相当。使用L-[¹⁸F]FBPA的正电子发射断层扫描（PET）可以清晰地显示格林黑色素瘤。总之，当L-[¹⁸F]FBPA用作恶性黑色素瘤BNCT中L-BPA的探针时，可以通过PET利用¹⁸F放射性在体内定位黑色素瘤并评估组织中的¹⁰B浓度。
