Distribution of actin in etoposide-induced human leukemia cell line K-562 using fluorescence and immunoelectron microscopy technique.
Localization of actin was studied in erythroleukemic cell line K-562 after treatment with etoposide for 72 hours in a range of concentrations 0.02-200 microM/L. Actin was visualised by fluorescence microscopy and streptavidingold method. These findings indicate that changes in actin after treatment with etoposide were dose-dependent. Significant changes in the cellular distribution of F-actin in K-562 cells were obtained after treatment with 20 and 200 microM/L etoposide. In comparison with control cells, the number of the cells decreased and cells were larger especially at 200 microM/L. F-actin was diffusely distributed throughout the cell at 20 microM/L. Treatment of cells with 200 microM/L etoposide showed F-actin diffusely distributed throughout the cell with local actin assemblies and also at the cell periphery. Immunogold labelling of actin was observed in cells treated with all doses of etoposide and control cells. Labelling was found in the nucleus and also in the cytoplasm. At the ultrastructural level, cells treated with 200 microM/L etoposide showed protrusions at the surface, in which increase of actin was often observed. Etoposide causes changes in actin distribution of K-562 cells, and the changes in expression of actin were not only restricted to cell with features of apoptosis.
Department of Clinical Pathomorphology, University School of Medical Sciences, Bydgoszcz. grzanka@ab-byd.edu.pl
Alina
A
Grzanka
Dariusz
D
Grzanka
D000199:Actins / Q000378:metabolism*; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D005047:Etoposide / Q000494:pharmacology*; D006801:Humans; D020014:K562 Cells / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D008856:Microscopy, Fluorescence; D016253:Microscopy, Immunoelectron
D000199:Actins; D000972:Antineoplastic Agents, Phytogenic; D005047:Etoposide