Hedychium coronarium extract arrests cell cycle progression, induces apoptosis, and impairs migration and invasion in HeLa cervical cancer cells.

Background: Hedychium coronarium Koen. (Zingiberaceae) is traditionally used as medicine in countries such as India, China, and Vietnam for treatment of various ailments including cancer. However, in spite of its implied significance in cancer treatment regimes, there are no reports so far involving the anticancerous attributes of H, coronarium ethanol extract (HCEE) on cancer cells and a more comprehensive study on its mechanism is still lacking.

Materials and methods: The cytotoxicity of HCEE was evaluated by MTT and clonogenic survival assay. Annexin V/propidium iodide (PI), Hoechst 33342 staining, and TUNEL assay were performed to detect apoptosis. Cell cycle analysis was performed using PI staining. JC-1 and 2',7'-dichlorodihydrofluorescein diacetate assay were used to check the levels of MMP and ROS, respectively. Western blot analysis was carried out to measure the expression levels of proteins. Migration and invasion activity were assessed by wound healing and Transwell membrane assay, respectively.

Results: Antiproliferative effect of HCEE was investigated in various cancerous and normal cell lines. Among these, HCEE significantly inhibited the survival of HeLa cells without affecting the viability of normal human umbilical vein endothelial cells. Annexin V/PI, Hoechst staining, and TUNEL assay showed HCEE induced apoptosis in HeLa cells in a dose-dependent manner. HCEE promoted cell cycle arrest at G1 phase in HeLa cells by upregulating the levels of p53 and p21 and downregulating the levels of cyclin D1, CDK-4, and CDK-6. Moreover, HCEE treatment upregulated the expression of Bax and downregulated the expression of Bcl-2. Additionally, HCEE activated the caspase cascade by increasing the activities of caspase-9, caspase-8, and caspase-3. The expression levels of Fas ligand and Fas were also upregulated. Further, HCEE inhibited the migratory potential of HeLa cells by downregulating MMP-2 and MMP-9 expression levels.

Conclusion: Our results indicate H. coronarium exerts antiproliferative and apoptotic effects against HeLa cells, and therefore may be used for treatment against cervical cancer.