Effects of S-trityl-L-cysteine, an Eg5 inhibitor, on proliferation and cell division in neuroblastoma

Abstract

Objective To determine the expression levels of Eg5 in neuroblastoma and elucidate the effect of Eg5 specific inhibitor S-trityl-L-cysteine (STLC) on cell proliferation and cell division in neuroblastoma. Methods Immunofluorescence and Western blot was performed for detecting the expression of Eg5 in neuroblastoma tissues and cells. After an induction of STLC, cell morphology was observed under phase contrast microscope. And cell proliferation, cell cycle and cell apoptosis were examined with CCK-8 assay and flow cytometry. MYCN expression was assayed by fluorescence in situ hybridization (FISH) after STLC induction. Nuclear staining by 4', 6-diamidino-2-phenylindole (DAPI) was performed for observing the morphological changes. Results Eg5 was expressed in neuroblastoma tissues and cells. There were changes of cell morphology and apoptotic bodies were observed. Eg5 inhibitor effectively prevented the proliferation and arrests cells at G2/M phase and promoted cell apoptosis in dose and time-dependent ways. STLC had no effect on the expression of MYCN. Conclusions Eg5 is expressed both in neuroblastoma tissues and cells. And STLC suppresses the proliferation and cell division, arrests cells at mitosis and induces cell apoptosis. Eg5 may become a therapeutic target for neuroblastoma. Key words: Neuroblastoma; Kinesin; Proto-oncogenes