A Novel Method for Screening of Anti-Cancer Drugs: Availability of Screening in Acidic Medium

The inside of the human body is maintained within a narrow pH range around 7.4, but cancer nests are acidified, mainly due to insufficient blood circulation and impaired respiration. The activities of all enzymes are strictly dependent on pH, and hence many metabolic processes catalyzed by the pH-dependent enzymes decline as pH decreases in such acidified diseased areas, leading us to argue that the efficacy of inhibitors varies under different pH conditions. However, there have been few reports to examine inhibitor efficacy in acidic conditions. The main reason for this insufficient investigation may be that no reliable method for the screening of such medicines has been developed. Our group has invented a useful method for this purpose, and has found that several medicines have high efficacy as anti-cancer reagents under acidic conditions. In this article, we introduce this novel method applied for a patent and recent findings that encourage us to use this simple method for developing new anti-cancer drugs.