Effect of polyamide nanoparticles on apoptosis of colon cancer cells induced by survivin antisense oligonucleotide

Abstract

In this study, we aimed to observe the effect of polyamidoamine (PAMAM) liposomes on the apoptosis of human colon cancer cells induced by survivin antisense oligonucleotides (ASODNs). PAMAM liposomes and PAMAM were mixed with survivin ASODNs to obtain antisense gene transfection complexes. In addition, the zeta potentials and encapsulation rates of the complexes were measured. The two gene-containing complexes were transfected into HT-29 colon cancer cells to observe changes in cell morphology, detect the inhibitory effect on tumor cells and changes in apoptosis, and observe changes in the cytoskeleton microfilament system using laser confocal microscopy. Caspase-3 activity in the cells was determined using a kinase activity assay, and p38 mitogen-activated protein kinase (p38 MAPK) activity in the cells was measured using immunoprecipitation analysis. The results showed that the zeta potential of the PAMAM liposome-survivin-ASODN complex was higher than that of the PAMAM-survivin-ASODN complex (P < 0.05). There was no significant difference in the gene encapsulation rates between the two complexes (P > 0.05). PAMAM liposomes may efficiently deliver survivin ASODNs to human colon cancer cells, reduce the expression of survivin protein and at the same time induce G2/M phase arrest in cells, and activate caspase-3 by activating p38 MAPK. Cleavage of caspase-3 destroys the structure of the intracellular skeletal microfilament system, finally resulting in apoptosis of colon cancer cells.