Comparision between sonodynamic effects with protoporphyrin IX and hematoporphyrin on the cytoskeleton of Ehrlich ascites carcinoma cells.

PURPOSE

Our previous work demonstrated that the enhancement of cytotoxicity by protoporphyrin IX (Pp) was significantly higher than hematoporphyrin (Hp), when they were compared at the same ultrasound-exposure conditions, since the cytoskeleton plays a crucial role in numerous cell functions and the effect of sonodynamic therapy (SDT) on cytoskeleton has not been reported yet. So, it is very important to investigate whether SDT has some influence on the cytoskeleton, and it would also be interesting to compare Pp-/ and Hp-mediated SDT on the cytoskeleton.

METHODS

Ehrlich ascites carcinoma (EAC) cells were exposed to ultrasound for up to 15 seconds (1.34 MHz, 1 w/cm(2)) in the presence of 20 microM of Pp or 20 microM of Hp. Cell viability was determined by the trypan blue exclusion test. Morphologic changes were observed under a scanning electron microscope. Cytoskeleton damages were shown by immunofluorescence staining of microtubules, actin microfilaments, and intermediate filaments of vimentin.

RESULTS

Our experiment showed that the extent of cytoskeleton damage in EAC cells increased as time was prolonged, and also which was more significant in the Pp-SDT group than that in the Hp-SDT group at the same time after exposure.

CONCLUSIONS

Results implied that the ultrastructural changes might account for cell destruction and the cytoskeletal components were involved in the cell-damaging process induced SDT treatment.