Ultrasonically induced alterations of cultured tumour cells.
OBJECTIVE
The aim of this study was to establish: (i) which phase of the cell cycle is most sensitive to ultrasonic action; and (ii) whether and in which way ultrasound can influence components of the cytoskeleton.


METHODS
HeLa cell monolayers grown on glass cover-slips in DEM medium were used in all experiments. For proliferation studies, the cell monolayers were trypsinized and the cells were resuspended in fresh medium. The structure of the cytoskeleton was studied by means of the indirect immunofluorescence method. The cells were sonicated by a cw ultrasound of 0.8 MHz at low SA intensities (50, 100 and 500 mW/cm2) for 5 and 10 min.


RESULTS
The analysis of proliferation demonstrated that cells were most sensitive when undergoing M- and S-phases of the cell cycle. The ultrasonically induced disassembly of cytoskeleton components was most marked in microtubules and microfilaments due to depolymerization of basic proteins (tubulin and actin). The reaction of intermediate filaments was distinctly weaker.


CONCLUSIONS
In-vitro treatment of tumour cells with low intensity ultrasound results in partial inhibition of proliferation as well as in partial disassembly of all components of the cytoskeleton. Ultrasonically induced changes of the cytoskeleton seem to be non-specific and temporary.
Hrazdira
I
I
Department of Biophysics, Faculty of Medicine, Masaryk University, Jostova 10, CZ 662 43 Brno, Czech Republic.
Skorpíková
J
J
Dolníková
M
M
D000199:Actins / Q000378:metabolism; D002453:Cell Cycle; D002455:Cell Division; D003599:Cytoskeleton / Q000000981:diagnostic imaging; D004273:DNA, Neoplasm / Q000378:metabolism; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D006367:HeLa Cells / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D014404:Tubulin / Q000378:metabolism; D014463:Ultrasonography
D000199:Actins; D004273:DNA, Neoplasm; D014404:Tubulin