Mechanism of cell death induced by cis-3, 4', 5-trimethoxy-3'-aminostilbene in ovarian cancer.
OBJECTIVE
Stilbene derivative, cis-3, 4', 5-trimethoxy-3'-aminostilbene (stilbene 5c), is highly potent to induce cell death in ovarian cancer cells. This study is to investigate its mechanism to induce cell death.


METHODS
UCI101 ovarian cancer cells were used for this study. Cell death was analyzed by Alamar blue staining. Cell cycle was analyzed by flow cytometry after PI staining. Mitochondrial potential and reactive oxygen species were determined by MitoTracker green and DCF-DA, respectively. Immunofluorescent staining was done with tubulin antibody following by confocal microscope examination. Cell lysates were collected after treatment with stilbene 5c for Western blotting analysis of various cell cycle regulators and signal transduction mediators.


RESULTS
Stilbene-treated cells die in both cell cycle-dependent and -independent pathways. Low concentration (30 nM) induces cell death without cell cycle arrest. This process involves disruption of mitochondrial potential and production of ROS by a Bcl-2-independent pathway. Higher concentration of stilbene 5c arrests cell cycle in G(2)/M phase, which is supported by dephosphorylation of Cdc2 and Cdc25C, and transiently elevation of spindle checkpoint BubR1. Although phosphorylation of Chk1 and Chk2 both increases after treatment, loss of Chk1 suppresses, whereas loss of Chk2 enhances, stilbene 5c-induced cell death. Phosphorylation of Akt and Stat3, but not MAPK, is suppressed after stilbene 5c treatment.


CONCLUSIONS
These studies provide a mechanistic insight in using stilbenes in ovarian cancer. Stilbenes could be potentially useful agents for ovarian cancer therapy and induce cell death through mitochondrial damage and cell cycle arrest.
Durrant
David
D
Massey Cancer Center, Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA.
Richards
Joanna E
JE
Walker
Winston T
WT
Baker
Kristen A
KA
Simoni
Daniele
D
Lee
Ray M
RM
D017209:Apoptosis / Q000187:drug effects*; D002453:Cell Cycle / Q000187:drug effects*; D016923:Cell Death / Q000187:drug effects*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology; D010051:Ovarian Neoplasms / Q000473:pathology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013267:Stilbenes / Q000494:pharmacology*
C476602:3,4',5-trimethoxy-3'-aminostilbene; D017382:Reactive Oxygen Species; D013267:Stilbenes