Phosphatidylinositol Derivatives Induce Gastric Cancer Cell Apoptosis by Accumulating AIF and AMID in the Nucleus

Abstract

Background: The present study investigated the mechanism underlying the apoptosis of MKN28 human gastric cancer cells induced by the phosphatidylinositol (PI) derivative 1,2-O-bis-[8-{2-(2-pentyl-cyclopropylmethyl)-cyclopropyl}-octanoyl]-sn-glycero-3-phosphatidyl-D-1-inositol (diDCP-LA-D-PI) and its enantiomer diDCP-LA-L-PI.

Materials and methods: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining, enzymatic caspase assay, real-time reverse transcription-polymerase chain reaction (RT-PCR), and western blotting were carried-out.

Results: Both diDCP-LA-D-PI and diDCP-LA-L-PI induced caspase-independent apoptosis of MKN28 cells, with the potential for diDCP-LA-L-PI being much greater than that of diDCP-LA-D-PI. diDCP-LA-D-PI and diDCP-LA-L-PI accumulated apoptosis-inducing factor (AIF) and AIF-homologous mitochondrion-associated inducer of death (AMID) in the nucleus.

Conclusion: diDCP-LA-D-PI and diDCP-LA-L-PI induce caspase-independent apoptosis of MKN28 cells by accumulating AIF and AMID in the nucleus, with different potentials.

Keywords: AIF; AMID; Phosphatidylinositol derivative; caspase-independent apoptosis; enantiomer.