Killing effect of laser irradiated hexyl 5-aminolevulinate on human erythroleukemia cell line K562 and drug-resistance cell line K562/ADM / 解放军医学杂志

ABSTRACT

Objective To investigate the photodynamic therapy(PDT)of human erythroleukemia cell line K562 and drug-resistance cell line K562/ADM using hexyl 5-aminolevulinate(He-ALA)in vitro.Methods Four groups were set:PDT group(photosensitizer with light irradiation),laser group(light irradiation only),dark-cytoxocity group(photosensitizer only)and normal control group(neither photosensitizer nor light irradiation).K562 cells and K562/ADM cells cultured were incubated with various concentrations of He-ALA(0.025,0.1,0.4 and 1.6mmol/L)for 4 hours,then illuminated with different light doses(4.5,9,18 and 36 J/cm2)using a laser with a wave length of 630nm.After 12 hours incubation,Wright's staining method was used to observe the cell's morphological changes,the survival rates of cells were analyzed by CCK8 assay,and the changes in colony-forming abilities of cells were analyzed by methylcellulose colony-forming assay.Results He-ALA or light irradiation alone had no evident cytotoxicity,while the application of He-ALA plus light irradiation effectively killed the leukemia cells.With the increase of the concentrations of He-ALA and the dosages of irradiation,the viability of cells decreased.Under the same conditions,the survival rate of K562 was significantly lower than that of K562/ADM(P