Abstract
RC-RNase purified from Rana catesbeiana (bullfrog) oocytes is a pyrimidine-guanine sequence-specific ribonuclease. RC-RNase is derived from the RNase superfamily genes exerting distinct ribonucleolytic activity and possesses cytotoxicity to tumor cells, but rarely to primary cells. In this study, we utilized RC-RNase to function with antiproliferative cytokines. The combination with TNF-α or TNF-β would not aggravate cell death. However, the combination with IFN-γ could induce synergistic cytotoxicity verified by XTT assays toward three hepatoma cell lines bearing different differentiation stages. The distinct cytotoxicity from RC-RNase or RC-RNase/IFN-γ on different hepatoma cells was correlated with the differentiation extent but not the proliferation rate of the cells. Despite the synergistic cytotoxicity and severe mitochondrial disruptions in the RC-RNase/IFN-γ-treated cells, we scarcely detected any significant feature of apoptosis or necrosis by FACS analysis on annexin-VI propidium iodide staining. The mechanisms of cell death triggered by RC-RNase or RC-RNase/IFN-γ require further investigation.
Original language | English (US) |
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Pages (from-to) | 1229-1236 |
Number of pages | 8 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 280 |
Issue number | 5 |
DOIs | |
State | Published - 2001 |
Keywords
- Hepatoma
- Interferon γ (IFN-γ)
- RC-RNase
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology