Abstract
AIM: To study the mechanism of differentiation-inducing action of 10- hydroxycamptothecin (HCPT) on human hepatoma Hep G2 cells. METHODS: The proliferating cell nuclear antigen (PCNA) expression was studied by immunocytochemical staining method. The cell cycle distribution and the wild- type protein p53 expression were measured by flow cytometry. Telomerase activity was assayed with telomeric repeat amplification protocol (TRAP). RESULTS: After treatment with HCPT at differentiation-inducing concentrations 5 - 20 μg · L-1 for 6 d, Hep G2 cells were mainly arrested at G2/M phase and the PCNA expression rate was lower than that of control cells. When Hep G2 cells grew in a medium containing HCPT 5 μg · L-1 for 6 d, the p53 expression level markedly increased in comparison with the control cells. The telomerase activity did not change in Hep G2 cells treated with HCPT 5 - 20 μg · L-1 for 8 d. CONCLUSION: The differentiation-inducing effect of HCPT on Hep G2 cells is related with the cell cycle arrest at G2/M phase, down- regulation of PCNA and up-regulation of wild-type protein p53.
| Original language | English |
|---|---|
| Pages (from-to) | 364-368 |
| Number of pages | 5 |
| Journal | Acta Pharmacologica Sinica |
| Volume | 21 |
| Issue number | 4 |
| State | Published - 2000 |
| Externally published | Yes |
Keywords
- 10-Hydroxycamptothecin
- Cell cycle
- Cell differentiation
- Experimental liver neoplasm
- Flow cytometry
- Immunohistochemistry
- Proliferating cell nuclear antigens
- Protein p53
- Telomerase