Abstract:

OBJECTIVE: To study the anti-tumor effect of cisplatin by chrysin (ChR) in vitro. METHODS: Cultured cells from human colorectal cancer (HCT-116),gastric cancer (BGC-823),nasopharyngeal carcinoma (CNE1) and liver cancer (HepG2) were treated by chrysin (40 μmol/L),cisplatin (5.0 μg/mL),and chrysin (40 μmol/L)+cisplatin (5.0 μg/mL) separately for 24 hours. The inhibitory rate of tumor cells was determined by MTT assay. The apoptosis rate of tumor cells was determined by Hoechst 33342 fluorescence staining. The sensitive cell line was identified by the inhibition rate and apoptosis index. The L₉(3³) orthogonal design of three levels of chrysin (10,20,40 μmol/L),three levels of cisplatin (1.3,2.5,5.0 μg/mL),and three time-points (12,24,36 h) was used to screen for the best combination effect of chrysin and cisplatin in the sensitive cells. RESULTS: Among all cell lines,the MTT assay showed that the inhibition rates from exposure to the combination of chrysin and cisplatin were significantly higher than that of the single treatment groups of chrysin and cisplatin (P < 0.01). Similarly,Hoechst 33342 staining showed that the apoptosis rates from the combined treatment were significantly higher than those from the single treatment groups (P < 0.01). From the combined treatment,the inhibitory rate in BGC-823 was (78.0±2.0)% and the apoptosis index was (72.3±6.5)%,indicating that this was the most sensitive among all tested cell lines. The results of in vitro orthogonal experiment showed that the most effective conditions were:40 μmol/L chrysin,5.0 μg/mL cisplatin,and 24 hours of treatment time. CONCLUSION: Chrysin enhanced the inhibitory effect of cisplatin via inhibition of cell proliferation and promotion of apoptosis in human tumor cell lines. Among the tested cell lines,the human gastric cancer cell line BGC-823 was the sensitive one to the combined effect of chrysin and cisplatin.

Key words: chrysin, cisplatin, orthogonal experiment design, anti-tumor