Abstract: Objective To explore the effect of shikonin on the proliferation and apoptosis of ovarian cancer cells and the expression of c-Jun N-terminal kinase ( JNK) signaling pathway.Methods Human ovarian cancer cell ( SKOV-3 ) cells cultured in vitro were divided into 4groups: control group ( 0 μmol / L ), low-dose Shikonin group ( 2. 5 μmol / L ), middle-dose Shikonin group (5 μmol / L) and high-dose Shikonin group (10 μmol / L). Cell proliferation and apoptosis were detected in each group. The expression levels of proliferating cell nuclear antigen (PCNA), cleaved Caspase-9 and Caspase-3 proteins, and c-Jun N-terminal kinase 1 / 2 ( JNK1 /2) phosphorylation were detected by Western blotting. Results The inhibitory effect of shikoninon the proliferation of SKOV-3 cells showed dependence of drug concentration, with the semi-inhibitory concentration (IC50) of 10. 59 μmol / L. The cells survival rate and colony formation rate weresignificantly decreased in the middle-dose Shikonin group and high-dose Shikonin group ( P <0. 05), the apoptosis rate was significantly increased (P < 0. 05), the expression levels of PCNAand (p-JNK1 / 2) / (JNK1 / 2) were significantly decreased (P < 0. 05), and the levels of cleavedCaspase-9 / Caspase-9 and cleaved Caspase-3 / Caspase-3 were significantly increased (P < 0. 05), ifcompared with those in the control group. Conclusion Shikonin can inhibit the proliferation ofSKOV-3 cells, inhibit JNK signaling pathway, and induce apoptosis.

Key words: ovarian cancer, shikonin, c-Jun amino-terminal kinase