In vitro antiproliferative activity of fresh pineapple juices on ovarian and colon cancer cell lines

Abstract

The main component that contributes to the high value of pineapple is bromelain which is a proteolytic enzyme and has been scientifically identified as a therapeutic agent. This study was conducted to obtain high quantity of bromelain from pineapple and to investigate the anticarcinogenic activity of fresh pineapple juices against A2780 ovarian and HT29 colon cancer cell lines. It was found that homogenization, ultrafiltration, precipitation and dialysis contributed to heavy loss of bromelain. Therefore, fresh pineapple juices from the flesh (PJ-F), core (PJ-C) and stem (PJ-S) were selected as a source of crude bromelain. Various bromelain concentrations of PJ-F, PJ-C and PJ-S (1 mu g/ml, 10 mu g/ml, 100 mu g/ml and 1000 mu g/ml) were exposed to the cancer cells and the cell viability was determined using Methylthiazol Tetrazolium Assay (MTT assay) after 24, 48 and 72 h. Besides, IC50 values were measured. Using normal cell (HSF1184) comparison, it was found that a 100 mu g/ml concentration of bromelain would efficiently inhibit the cancer cells without affecting the surrounding normal cells. Microscopic examinations were carried out to elucidate the modes of cell death on the basis of morphological alterations using florescent and inverted phase contrast microscopes. Furthermore, the colony forming abilities of fresh pineapple juices on A2780 and HT29 cells were examined. The results demonstrated that PJ-F, PJ-C and PJ-S effectively suppressed the colony formation in cancer cells. The findings suggest that PJ-F, PJ-C and PJ-S may have the potential to induce anticarcinogenic effects through an apoptosis to A2780 and HT29 cells in vitro.