In the present invention, while being easily absorbed into cells, it is an anti-cancer agent that is not metabolized in the living body without changing its chemical structure, and does not induce immunity, and is different from other anti-cancer agents. An anticancer agent that can be used in combination is provided. As a result of diligent research, the present inventors have newly found that ozone water that can be stored for a long period of time has an anticancer effect. In addition, it was also found that the effect is significantly increased when used in combination with existing anticancer drugs.本願発明では、細胞内に容易に吸収されつつも、生体内で代謝され化学構造が変化することなく、かつ免疫誘導を起こさない、抗がん剤であって、他の抗がん剤との併用が可能な抗がん剤を提供する。本願発明者らは鋭意研究の結果、長期保存が可能なオゾン水に抗がん作用があることを新たに見出した。さらに既存の抗がん剤と併用した場合、その効果が大幅の上昇することもわかった。
