[Quantitative analysis of nuclear proteome in apoptosis hepatoma cells induced by hydroxycamptothecin].

The experimental foundation for investigating the pharmacological action of hydroxycamptothecin at subcellular quantitative proteomic level can be obtained depending on the information of differentially expressed nuclear proteins in hydroxycamptothecin-treated cells and control cells. The apoptosis was induced by hydroxycamptothecin in hepatoma cells, the nucleus of cells were isolated and verified with western blot. Nuclear proteins labelled with cleavable isotope-coded affinity tag (c-ICAT) reagent were digested and purified. The expression ratio of the identical nuclear protein derived from apoptosis cell and control cell can be gained using shotgun proteomic method based on multiple dimensional liquid chromatography-linear ion trap/orbitrap mass spectrometer combined with c-ICAT strategy. A total of 42 nuclear proteins were significantly (P<0.05) altered in hydroxycamptothecin-treated cells, among them, 12 proteins showed significantly down-regulation, and 30 proteins showed up-regulation compared with control cells. The function of these proteins were likely involved in life processes of cells such as proliferation, apoptosis, differentiation, energy metabolism, nucleic acid synthesis and metabolism, structure of cell skeleton.