Study On The Changes Of Nuclear Matrix Proteins During The Apoptosis Of The Osteosarcoma MG-63 Cells

In this study, the curcumin (Cur) was used to induce the human osteosarcoma MG-63 cells into apoptosis, and its effects were investigated by selective extraction-whole mount optic and transmission electron microscopy and techniques of proteomic. The differentially expressed nuclear matrix proteins were analyzed in order to explore the molecular mechanisms in a system level.The results revealed that the osteosarcoma MG-63 cells were induced into apoptosis after treated with 7.5μg/mL Cur as the proliferation of MG-63 cells were inhibited, and the cell cycle were arrested in G0/G1 phase. The malignant morphological and ultrastructural characteristics were changed, while the expression level of apoptosis promote gene was upregulated, and the expression level of apoptosis suppressor gene was downregulated. And at the same time,the configuration of nuclear matrix-intermediate filament(NM-IF)was altered. Nuclear matrix proteins(NMPs), selectively extracted from MG-63 cells treated with or without Cur, were subjected to proteomic analysis.There were 21 of 27 differentially expressed spots were identified, including the DNA damage inducible transcript, Discoidin, DNA ploymase zeta, prohibitin, glutamate dehydrogenase, Vimentin, Human Nucleophosmin, Heat-shock 70 etc. associated with remodeling of cellular configuration. Except vimentin, prohibitin, HSP70, nucleophosmin, all other proteins were found as NMPs for the first time.In conclusion, the configuration and composition of nuclear matrix were changed following the MG-63 cell apoptosis, and it is possible to get a system understanding of the molecular mechanisms from the studies of nuclear matrix.