Enhancing the Effective Chemotherapy: The Combined Inhibition of Rhinacanthin-C, 5-Fluorouracil, and Etoposide on Oral Cancer Cells.

OBJECTIVE

To investigate the effects of rhinacanthin-C (Rh-C), 5-FU, and etoposide on growth inhibition, as well as the effects of a combination of these inhibitors on the oral cell lines SCC9 and HSC4.

METHODS

Cancer cell growth inhibition and inhibition combination were determined using the SRB assay. Cell viability and early apoptosis were determined using flow cytometry on cells stained with Annexin 5 and PI. Western blotting was performed to study the molecular mechanism of these inhibitors on oral cancer cells.

RESULTS

The results showed that etoposide, 5-FU, and Rh-C exhibited more potent anti-proliferative effects on HSC4 cells compared to SCC9 cells in a time- and concentration-dependent manner. The combination of Rh-C and 5-FU was more effective in inhibiting cell growth than the drugs used alone. The combination of 5-FU and Rh-C resulted in a decrease in live HSC4 cells, with the highest percentage of cell death observed at a ratio of 40:6 μM. Furthermore, the combination of 5-FU and Rh-C reduced P-Akt levels leading to a decrease in cell survival.

CONCLUSIONS

HSC4 cells were found to be more sensitive to the inhibitory effect of these drugs compared to SCC9 cells. These findings suggest that the use of Rh-C as a complementary therapy with 5-FU may have the potential for the treatment of oral cancer. the underlying mechanisms responsible for this difference in sensitivity between the two cell lines need to be further investigated.