The Effects of Frankincense on Oral Squamous Cell Carcinoma Cell Line

Background Cytotoxic effects of Frankincense resin have been shown on some cancer cell lines. Due to its low side effects, this study was designed to evaluate the anticancer properties of water soluble elements of Frankincense oleo-gum-resin on human oral squamous cell carcinoma cell line. Methods Oleo-gum-resin was macerated in ethanol. After filtration, the water soluble fraction of dried residue was extracted. KB cells were treated with 0, 62.5, 125, 250 and 500 μg/mL concentrations of obtained Frankincense aqueous fractions and with Doxorubicin as positive control. Frankincense induced cell cytotoxicity; apoptosis and proliferation were investigated using WST assay, Annexin V-FITC/PI, and Ki-67 staining, respectively. Data were analyzed using Kruskal-Wallis test by SPSS 17 software. Results IC₅₀ of 137.21 μg/mL was obtained from Frankincense aqueous fraction after 48 hours. The percentage of apoptotic cells was elevated in a time- and dose-dependent manner. There was no statistical difference in the Ki-67 expression of KB cells, using different concentration of Frankincense aqueous fraction after 24 and 48 hours (P = 0.083). Doxorubicin inhibited cells growth essentially through apoptosis. Conclusions Frankincense aqueous fractions seem to suppress KB cell growth through the induction of apoptosis and necrosis rather than the inhibition of proliferation and hence might be a potential anticancer agent. Structural analysis and purification of potent components are suggested for determining more definitive results.