Chikusetsusaponin IVa methyl ester induces G1 cell cycle arrest, triggers apoptosis and inhibits migration and invasion in ovarian cancer cells.
BACKGROUND
Panacis Japonici Rhizoma (PJR) is one of the most famous Chinese medical herbs that is known for exhibiting potential anti-cancer effects.


OBJECTIVE
This study aims to isolate and investigate the anti-cancer potential of saponins from PJR in ovarian cancer cells.


METHODS
The compounds were separated by comprehensive chromatographic methods. By comparison of the 1H- and 13C NMR data, as well as the HR-ESI-MS data, with the corresponding references, the structures of compounds were determined. MTT assay was performed to evaluate cell viability, along with flow cytometry for cell cycle analysis. JC-1 staining, Annexin V-PI double staining as well as Hoechst 33; 342 staining were used for detecting cell apoptosis. Western blot analysis was conducted to determine the relative protein level. Transwell assays were performed to investigate the effect of the saponin on cell migration and invasion and zymography experiments were used to detect the enzymatic activities.


RESULTS
Eleven saponins were isolated from PJR and their anti-proliferative effects were evaluated in human ovarian cancer cells. Chikusetsusaponin IVa methyl ester (1) exhibited the highest anti-proliferative potential among these isolates with the IC50 values at less than 10 µM in both ovarian cancer A2780 and HEY cell lines. Compound 1 induced G1 cell cycle arrest accompanied with an S phase decrease, and down-regulated the expression of cyclin D1, CDK2, and CDK6. Further study showed that compound 1 effectively decreased the cell mitochondrial membrane potential, increased the annexin V positive cells and nuclear chromatin condensation, as well as enhanced the expression of cleaved PARP, Bax and cleaved-caspase 3 while decreasing that of Bcl-2. Moreover, compound 1 suppressed the migration and invasion of HEY and A2780 cells, down-regulated the expression of Cdc42, Rac, RohA, MMP2 and MMP9, and decreased the enzymatic activities of MMP2 and MMP9.


CONCLUSIONS
These results provide a comprehensive evaluation of compound 1 as a potential agent for the treatment of ovarian cancer.
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Xin
X
Chen
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Qiu-Shuang
QS
Wu
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Fan-Cheng
FC
Meng
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Zheng-Hai
ZH
Tang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Xiuping
X
Chen
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Li-Gen
LG
Lin
College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
Ping
P
Chen
Department of Obstetrics and Gynecology-Division of Reproductive Science in Medicine, Department of Pathology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
Wen-An
WA
Qiang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
Yi-Tao
YT
Wang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China. Electronic address: qwzhang@umac.mo.
Qing-Wen
QW
Zhang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China. Electronic address: jinjianlu@umac.mo.
Jin-Jian
JJ
Lu
D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D019938:Cyclin D1 / Q000378:metabolism; D051357:Cyclin-Dependent Kinase 2 / Q000378:metabolism; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D015394:Molecular Structure; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D012503:Saponins / Q000737:chemistry / Q000494:pharmacology*
D000972:Antineoplastic Agents, Phytogenic; C530104:CCND1 protein, human; D004365:Drugs, Chinese Herbal; D012503:Saponins; D019938:Cyclin D1; C098580:chikusetsu saponin IVa; D009828:Oleanolic Acid; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; D053148:Caspase 3
Apoptosis; Cell cycle arrest; Chikusetsusaponin IVa methyl ester; Metastasis; Ovarian cancer; Panacis Japonici Rhizoma