PDF/月刊誌論文/code:pg_0408_06 マテリアル インテグレーション 2004年8月号
INTER MATERIAL ヘリカル/らせん構造物質・材料とその応用(2)

CMCの癌治療への応用
■著者
(財)応用生化学研究所　幸村 定昭

■要約
This paper describes a stimulatory effect of carbon micro coil (CMC) on the generation of hydroxyl radical (・OH) in aqueous solutions by ultrasound exposure and an applicability of CMC to sonodynamic therapy of cancer. Aqueous solutions of the nitrone spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) exposed to 28 kHz ultrasound yielded a minute amount of an adduct of DMPO and ・OH. When CMC was added into the aqueous solutions and exposed to ultrasound, the level of ・OH markedly increased in a dose- and time-dependent manner. Human hepatocellular carcinoma HuH 7 cell culture was treated by ultrasound at a frequency of 28 kHz for 10 min three times in the presence or absence of sterilized CMC below 35 ℃. We found that cell density was significantly decreased by nearly 70% in the presence of 2 mg CMC in 2 ml of culture medium as compared with that in the absence of CMC. It was also demonstrated that CMC could enhanced a cytotoxic effect of ultrasound irradiation against cultured mouse sarcoma MethA cells. These results suggest that CMC is a potent sonosensitizer and applicable to cancer therapy in combination with ultrasound.