Cytotoxic effects of lysates of Acanthamoeba polyphaga (CCAP 1501/3A) and Acanthamoeba sp. (HKL isolate) on MCF-7 cells

Abstract

Cytotoxic effects of two Acanthamoeba lysates were studied on MCF-7 cell line. The amoebae used are Acanthamoeba polyphaga (CCAP/3A) and Acanthamoeba sp. (HKL isolate). The cytotoxic effects of Acanthamoeba lysates were tested against MCF-7 cell line using Trypan Blue Exclusion method. The cells were exposed to the lysates for 72 hours before they were trypsinized and stained with the trypan blue dye. Results obtained in this study showed that the inhibitory concentration value that kills 50% of the cell population (IC50) was different between the two amoeba lysates. The ICso value of Acanthamoeba sp. (HKL isolate) lysate is 42 µg/mL while for the Acanthamoeba polyphaga (CCAP/3A) is 89 µg/mL. The difference in these ICso values is probably due to their status of pathogenicity. The Acanthamoeba sp. (HKL isolate) was a pathogenic species and was isolated from a keratitis patient. Previous reports indicated that protein such as ecto-ATPase and hydrolytic enzymes (proteases and phospholipase) contribute to amoeba pathogenicity. From this study, it is suggested that the Acanthamoeba sp. (HKL isolate) lysate is more potent and thus it is suitable to become an anti-cancer agent. However, further study must be carried out to confirm its potential to become an anti­ cancer agent without producing the side effects to non-target cells.