[Proliferation inhibition and apoptosis induction of K562 cells by D-limonene]

This study was aimed to investigate the effect of D-limonene on K562 leukemia cells and its mechanism. Inhibitory effect of D-limonene on proliferation of K562 leukemia cells was assayed by MTT method and cell apoptosis was detected by flow cytometry and DNA agarose gel electrophoresis, the morphologic change of K562 cells was observed by microscopy. The results showed that when K562 cells were treated with 0.125 - 1.0 mmol/L of D-limonene for 48 hours, the proliferation of K562 cells was obviously inhibited in dose-dependent manner. Typical morphological changes and the typical DNA ladder on agarose gel electrophoresis for analysis of cellular apoptosis were significantly appeared in D-limonene treated K562 cells. Simultaneously, the sub-G1 peak was found in FCM analysis. It is concluded that the D-limonene can inhibit proliferation of K562 cells in dose-dependent manner, cause cell detained at G1 phase and induce apoptosis of K562 cells.