Abstract: ObjectiveTo study the effects of osthole on the proliferation, invasion and migration of nasopharyngeal carcinoma cells CNE2, and to investigate the possible molecular mechanism involved in epithelial to mesenchymal transition (EMT) of CNE2. MethodsCNE2 cells were cultured in vitro and were treated with 0, 20, 40 and 80 μg/ml osthole for 24 or 48 hours, and then methyl thiazolyl tetrazolium (MTT) assay and Transwell assay were used to explore their effects on the cell proliferation, invasion and migration while cells treated with 0 μg/ml osthole were used as the control group. Meanwhile, the mRNA and protein levels of markers of EMT (Ecadherin and vimentin ) and Wnt/βcatenin signaling (βcatenin and cyclin D1) were detected by reverse transcriptionpolymerase chain reaction (RTPCR) and Western blotting respectively. ResultsAfter treatment for 24 and 48 hours, the inhibitory rates of treatment with various concentration of osthole (0, 20, 40, 80 μg/ml) were 0.00%±0.00%, 7.45%±0.87%, 14.12%±2.29%, 27.26%±0.43% and 0.00%±0.00%, 13.44%±0.84%, 29.03%±0.78%, 57.49%±1.70%, with significant differences (F=174.33, P<0.001; F=1 041.40, P<0.001), and the following contrast between each two groups met the statistical significance (all P＜0.01). The migration cells per field of CNE2 cells treated with 0, 20, 40, 80 μg/ml osthole for 48 hours were 52.13±4.49, 29.00±4.49, 18.50±1.93, 13.75±2.77, which exhibited a significant difference (F=200.37, P＜0.001), and the following contrast between each two groups met the statistical significance (all P＜0.01). The invasion cells per field of CNE2 cells treated with 0, 20, 40, 80 μg/ml osthole for 48 hours were 46.63±2.87, 24.13±2.87, 16.75±5.29, 11.00±1.77 respectively, which exhibited a significant difference (F=131.92, P＜0.001), and the following contrast between each two groups met the statistical significance (all P＜0.01). Meanwhile, the relative mRNA and protein expressions of Ecadherin in 0, 20, 40 and 80 μg/ml osthole treatedcells (exposure for 48 hours) were 1.00±0.13, 2.61±0.03, 3.12±0.09, 3.60±0.06 (F=20.92, P<0.001) and 0.22±0.03, 0.35±0.01, 0.60±0.04, 0.82±0.03 (F=178.63, P＜0.001) respectively, and the differences were statistically significant, and further pairwise comparison showed the differences were statistically significant (all P＜0.05). Furthermore, the relative mRNA and protein levels of vimentin, βcatenin, cyclin D1 in 0, 20, 40 and 80 μg/ml osthole treatment for 48 hours were statistically significant difference (mRNA level of vimentin: 1.00±0.12, 0.68±0.03, 0.56±0.01, 0.40±0.09, F=9.48, P<0.010; mRNA level of βcatenin: 1.00±0.14, 0.78±0.04, 0.69±0.07, 0.46±0.12, F=4.84, P<0.050; mRNA level of cyclin D1: 1.00±0.09, 0.82±0.03, 0.58±0.09, 0.40±0.03, F=9.49, P<0.010; protein level of vimentin: 0.85±0.02, 0.74±0.01, 0.34±0.01, 0.27±0.01, F=610.58, P<0.001; protein level of βcatenin: 0.83±0.00, 0.44±0.02, 0.39±0.00, 0.23±0.03, F=985.74, P＜0.001; protein level of cyclin D1: 0.86±0.02, 0.67±0.00, 0.35±0.01, 0.25±0.01, F=910.57, P＜0.001), and further pairwise comparison showed the differences were statistically significant (all P＜0.05). ConclusionOsthole can inhibit the proliferation, invasion and migration of CNE2 cells, which is related to the regulation of Wnt/βcatenin signal pathway and then suppressing of EMT.

Key words: Osthole, Nasopharyngeal neoplasms, Cell proliferation, Neoplasm invasiveness, Cell movement