Study of the development a new type of treatment of urogenital cancer by using surface modified fine metal particles.

我们试图开发一种新型的治疗癌症的方法，即用特殊的表面修饰的金属微粒，特别是包覆有TiO2光催化剂的微粒。1)成功地制备了包覆金的纳米金粒子，并证明其在组织和细胞中非常稳定和安全。在360 nm紫外光照射下，包覆的金粒子表现出光催化活性。它们的光催化能力依赖于包被在金颗粒上的二氧化钛的量。2)通过非病毒基因转移系统强制导入野生型p53基因，可显著抑制裸鼠体内生长的人前列腺癌PC-3肿瘤的生长及p53基因的表达。3)360 nm紫外光照射与以生理强化的方法将包被的金颗粒导入人膀胱癌T-24裸鼠体内可有效地抑制人膀胱癌T-24肿瘤的生长。这些结果表明，包覆纳米金粉和紫外光的结合可能是一种新型的癌症治疗方法。

We tried to develop a new type of treatment of cancer by using specifically surface modified fine metal particles, especially particles coated by TiO_2 photacatalyst. They might be also applicable to gene therapy without using virus vector.1) TiO_2 coated fine gold particles were successfully developed and they were shown to be very stable and safe in tissues or cells. The TiO_2 coated gold particles showed photacatalytic activities when there were exposed to 360 nm UV light. The photacatalytic capacity of them were dependent on the amount of TiO_2 coated on the gold particles.2) The growth of human prostate cancer PC-3 tumors which were grown on nude mice, and lost P53 genes expression, were suppressed dramatically by the enforced introduction of wild type P53 gene using non- viral gene transfer systems.3) The growth of human bladder cancer T-24 tumors on nude mice were effectively suppressed by the combined treatment of 360 nm UV light exposure and TiO_2 coated gold particles which was introduced into the cancer tissues by physiological enforced method. These results suggest that the combination of TiO_2 coated fine gold particle and UV light could be one of the new types of cancer treatment.