Abstract
Background: PKC412, formerly CGP41251, N-benzoylstaurosporine, was initially developed as a selective protein kinase C (PKC) inhibitor, and it preferentially inhibits conventional PKC family members. In this study, the expression of PKCα was examined in human osteosarcoma and MFH cell lines, and the inhibitory effect of PKC412 on the proliferation of the cell lines was evaluated. Materials and Methods: Three human osteosarcoma cell lines (KTHOS, MG63 and KHOS) and four human MFH cell lines (TNMY1, GBS-1, Nara-F and Nara-H) were used. The expression of PKCα and phosphorylated PKCα were analyzed using both Western blotting analysis and immunocytochemical analysis. The effect of PKC412 on cell proliferation was evaluated using the MTS assay technique. Results: PKC412 inhibited cell proliferation of all seven cell lines in a dose- and time-dependent manner. Both Western blotting analysis and immunocytochemical analysis revealed that not only PKCα□ but also phosphorylated PKCα□ were expressed in all cell lines incubated with the culture medium without any stimuli. PKC412 suppressed phosphorylation of PKCα in all cell lines at a concentration of 1 μM. Conclusion: The inhibition of cell proliferation of the human osteosarcoma and MFH cell lines by PKC412 might be due to reduced PKCα activity. This suggests PKC412 might be a potent chemotherapeutic agent for human sarcomas.
- Received October 17, 2007.
- Revision received December 4, 2007.
- Accepted January 7, 2008.
- Copyright© 2008 International Institute of Anticaner Research (Dr. John G. Delinassios), All rights reserved