Ursolic Acid Florotriazole Treatment Causes Inhibition of Squamous Cell Carcinoma through Fas Signaling Pathway

Purpose: To investigate the effect of ursolic acid florotriazole (UFT), on SCC-15 oral squamous cancer cells. Methods: Confocal laser microscope with a 490 nm argon laser was used to record the fluorescence of the cells and capture the images. Flow cytometry and Cell Quest program were used to analyze the DNA content of the stained cells. Apoptosis was characterized by YO-PRO-1 staining. Results: Treatment of SCC-15 cells with UFT for 48 h significantly reduced cell viability in a dosedependent manner. At 20 μg/mL concentration of UFT, SCC-15, cell viability was reduced to 19 % compared to 100 % in the untreated cells (p = 0.0002). UFT treatment enhanced the proportion of apoptotic cells which was evident from YO-PRO-1 staining. In UFT-treated cultures, the population of cells in sub-G1 phase increased to 38.54 % compared to 7.32 % for control after 48 h. Expression of Fas in UFT-treated cells was also higher (p = 0.0002) than in untreated cells. In C3H/HeJ mice, administration of UFT daily for 14 days caused a significant (p = 0.0002) reduction in tumor volume and weight after 30 days of SCC-15 carcinoma cell administration. Conclusion: UFT treatment inhibits viability and induces apoptosis in squamous cell carcinoma cells through suppression of Fas expression. Therefore, UFT may be useful for the treatment of squamous cell cancer.