Antiproliferation and apoptosis induction of paeonol in HepG2 cells.
OBJECTIVE
To investigate the antiproliferative effect of paeonol (Pae) used alone or in combination with chemotherapeutic agents [cisplatin (CDDP), doxorubicin (DOX) and 5-fluorouracil (5-FU)] on human hepatoma cell line HepG2 and the possible mechanisms.


METHODS
The cytotoxic effect of drugs on HepG2 cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Morphologic changes were observed by acridine orange (AO) fluorescence staining. Cell cycle and apoptosis rate were detected by flow cytometry (FCM). Drug-drug interactions were analyzed by the coefficient of drug interaction (CDI).


RESULTS
Pae (7.81-250 mg/L) had an inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner, with the IC50 value of (104.77 +/- 7.28) mg/L. AO fluorescence staining and FCM assays showed that Pae induced apoptosis and arrested cell cycle at S phase in HepG2 cells. Further, different extent synergisms were observed when Pae (15.63, 31.25, 62.5 mg/L) was combined with CDDP (0.31-2.5 mg/L), DOX (0.16-1.25 mg/L), or 5-FU (12.5-100 mg/L) at appropriate concentrations. The IC50 value of the three drugs decreased dramatically when combined with Pae (P < 0.01). Of the three different combinations, the sensitivity of cells to drugs was considerably different.


CONCLUSIONS
Pae had a significant growth-inhibitory effect on the human hepatoma cell line HepG2, which may be related to apoptosis induction and cell cycle arrest. It also can enhance the cytotoxicity of chemotherapeutic agents on HepG2 cells, and the S phase arrest induced by Pae may be one of the mechanisms of these interactions.
Xu
Shu-Ping
SP
Institute of Clinical Pharmacology of Anhui Medical University, Key Laboratory of Antiinflammatory and Immunological Pharmacology in Anhui Province, Hefei 230032, Anhui Province, China.
Sun
Guo-Ping
GP
Shen
Yu-Xian
YX
Wei
Wei
W
Peng
Wan-Ren
WR
Wang
Hua
H
D000098:Acetophenones / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D004357:Drug Synergism; D006801:Humans; D014407:Tumor Cells, Cultured
D000098:Acetophenones; D000970:Antineoplastic Agents; C013638:paeonol