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的治疗癌症的方法，即用表面改性的细金属颗粒，特别是包覆二氧化钛光催化剂的颗粒。它们也可能适用于不使用病毒载体的基因治疗。1)成功制备了TiO_2包覆的细金颗粒，并证明其在组织或细胞中是非常稳定和安全的。在360 nm紫外光照射下，TiO_2包覆的金颗粒表现出光催化活性。它们的光催化性能与包覆TiO_2的量有关。2)利用非病毒基因转移系统强行引入野生型P53基因，可显著抑制裸鼠生长的人前列腺癌PC-3肿瘤的生长，使P53基因表达丧失。3) 360 nm紫外光照射与生理强化法引入TiO_2包覆金颗粒联合作用，可有效抑制裸鼠膀胱癌T-24肿瘤的生长。这些结果表明，TiO_2包覆的细金颗粒与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.