Development of a New Pin-point Treatment of Cancer Cells Using Hydrogen Storage Alloy as Hydrogen Supplier

为开发肿瘤细胞的定点治疗方法，研究了贮氢合金（HSA）的放氢行为，以及不同合金成分和试样形状的HSA放氢对生物细胞的影响。所得结果总结如下。1)气态氢和氢离子以及氢自由基的量根据合金成分而变化。因此，可以通过调节合金成分来控制氢释放行为。2)从存活概率（POS）测量的观察中，在癌细胞和一部分正常细胞中观察到POS的减少，并且发现释放的氢的影响取决于细胞的种类。3)在大约2~ 2的区域观察到选择性癌细胞死亡。样品外5 mm，与样品形状无关。4)通过ESR实验和荧光试剂检测过氧化氢，检测到了氢自由基、羟基自由基和过氧化氢，提示这些氢物种对癌细胞的死亡有影响。

To develop a pin-point treatment of cancer cells, hydrogen discharging behavior of hydrogen storage alloy(HSA) and the effect of hydrogen discharged from the HSA with different alloy composition and sample shape on biological cells have been studied. The results obtained are summarized as follows. 1) The amount of gaseous hydrogen and hydrogen ions as well as hydrogen radicals varied depending upon alloy composition. It is, therefore, possible to control the hydrogen discharging behavior by adjusting the alloy composition. 2) From the observation of the probability-of-survival(POS) measurement, a reduction in the POS was observed in cancer cells and a part of normal cell, and it was found that the influence of discharged hydrogen depends on the kind of cells. 3) A selective cancer cell death was observed in the region of approximately 2~ 2. 5 mm outside the samples, independent of sample shape. 4) From the ESR experiment and the detection of hydrogen peroxide using fluorescent regent, hydrogen radical, hydroxyl radical and hydrogen peroxide were detected and it was suggested that these hydrogen species would affect to cancer cell death.