[Mechanism of combined use of cyclopamine and hydroxycamptothecin in inducing the apoptosis of human oral squamous cell carcinoma cell line].
OBJECTIVE
To study the mechanism underlying the effect of combined use of cyclonpamine and hydroxycamptothecin in inducing the apoptosis of human oral squamous cell carcinoma cell line (OSCC) HSQ-89.


METHODS
CCK8 assay was used to investigate the inhibitory effect of cyclopamine on HSQ-89 cells. Flow cytometry (FCM) was employed to examine the cell apoptosis following combined treatment with cyclonpamine and hydroxycamptothecin. Reverse transcription polymerase chain reaction (RT-PCR) was applied to detect the mRNA expressions of Bcl-2, Bcl-xl, and Bid in HSQ-89 cells after the treatments.


RESULTS
Combined treatment with cyclonpamine and hydroxycamptothecin significantly inhibited the cell proliferation compared with hydroxycamptothecin treatment alone, also resulting in a significantly higher apoptosis rate of the cells (P<0.05). The mRNA level of Bcl-2 was significantly decreased after the treatments, especially after the combined treatment. Cyclopamine produced no significant effect on the mRNA levels of Bcl-xl and Bid in the cells.


CONCLUSIONS
The combined use of cyclopamine and hydroxycamptothecin significantly down-regulates the expression on of bcl-2 to induce the apoptosis of human OSCC cell line HSQ-89.
Jiang
Sui
S
Department of Stomatology, Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou 510080, China. jiangsui@126.com
Chen
Xi-lin
XL
Ding
Yong
Y
Chen
Zhong-wei
ZW
Zhu
Li-jun
LJ
Feng
Hang
H
Wang
Qi-ming
QM
Zhen
Mao-chuan
MC
Wang
Qian
Q
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D045744:Cell Line, Tumor; D004357:Drug Synergism; D006801:Humans; D009062:Mouth Neoplasms / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014704:Veratrum Alkaloids / Q000494:pharmacology*
D000970:Antineoplastic Agents; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D014704:Veratrum Alkaloids; C527042:hydroxycamptothecinum; D002166:Camptothecin; C000541:cyclopamine