Electrolyzed Hydrogen Water Improves Chemosensitivity to Anticancer Drugs by Potently Suppressing Autophagy.

Autophagy is an intracellular recycling system that contributes to the maintenance of cellular homeostasis. However, by providing tolerance to various stressors, autophagy promotes the survival and proliferation of cancer cells and confers resistance to chemotherapy. Anticancer drugs activate autophagy, leading to drug resistance in cancer cells. Autophagy inhibitors, such as chloroquine and hydroxychloroquine, enhance the antitumor effects of anticancer drugs when used in combination with them. However, these inhibitors are associated with several adverse effects. Here, using genome-wide RNA sequencing analysis, we deciphered a novel function of electrolyzed hydrogen water (EHW) in suppressing autophagy by activating mammalian target of rapamycin complex 1 signalling. The combination of EHW with anticancer drugs, such as 5-fluorouracil or paclitaxel, which activate autophagy, significantly decreased the viability of cervical and colorectal cancer cells. Mechanistically, molecular hydrogen and trace elements in EHW may suppress autophagy and potentiate anticancer effects. Considering its safety, we propose that EHW can act as a novel adjuvant to anticancer therapy.