Gambogic acid reduced bcl-2 expression via p53 in human breast MCF-7 cancer cells.
OBJECTIVE
In this study, we investigated the correlation between p53 and bcl-2 in gambogic acid (GA)-induced apoptosis.


METHODS
MTT assay was employed to evaluate MCF-7 cell viability after GA treatment. Cell morphological changes were observed follow-up under the inverted microscope after GA withdrawal. To observe the cell apoptosis, DAPI staining was used. Meanwhile, p53 small interfering RNA (si-RNA) was adopted to knock p53 down. All expressions of p53 and bcl-2 were evaluated by Western blot analysis.


RESULTS
MTT assay showed that GA inhibited MCF-7 cell growth effectively in a time-dependent manner. With 0.5 h GA treatment, p53 was significantly increased, whereas bcl-2 was reduced potently with 6 h GA treatment. After GA withdrawal, p53 expressions were maintained in high levels. Furthermore, bcl-2 decreasing was attenuated after co-treatment with PFT alpha, a p53 transcription blocker. Same result was observed after p53 knock-down by p53 si-RNA.


CONCLUSIONS
Gambogic acid induced human breast cancer cells MCF-7 apoptosis by reducing bcl-2 expression via p53.
Gu
Hongyan
H
Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, P.O. Box 209, 24 Tongjia Xiang, 210009 Nanjing, Jiangsu, China.
Rao
Shuyun
S
Zhao
Jie
J
Wang
Jia
J
Mu
Rong
R
Rong
Jingjing
J
Tao
Lei
L
Qi
Qi
Q
You
Qidong
Q
Guo
Qinglong
Q
D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015536:Down-Regulation / Q000187:drug effects; D004353:Drug Evaluation, Preclinical; D005260:Female; D006801:Humans; D008954:Models, Biological; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000494:pharmacology; D016159:Tumor Suppressor Protein p53 / Q000037:antagonists & inhibitors / Q000502:physiology*; D044004:Xanthones / Q000494:pharmacology*
D000970:Antineoplastic Agents; D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D016159:Tumor Suppressor Protein p53; D044004:Xanthones; C052659:gambogic acid