Oridonin induces apoptosis via PI3K/Akt pathway in cervical carcinoma HeLa cell line.
OBJECTIVE
To investigate the apoptosis-inducing effect of oridonin, a diterpenoid isolated from Rabdosia rubescens, in the human cervical carcinoma HeLa cell line.


METHODS
A morphological analysis, nuclear condensation, and fragmentation of chromatin were monitored using Hoechst 33342 staining. Cell viability was assessed using the 3-(4, 5-dimethylthiazol-(2)-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. Cell apoptosis and the apoptosis-related activation in the HeLa cell line were evaluated by flow cytometry and Western blotting.


RESULTS
Oridonin suppressed the proliferation of the HeLa cell line in a dose- and time-dependent fashion. Oridonin treatment downregulated the activation of protein kinase B (Akt), the expression of forkhead box class O (FOXO) transcription factor, and glycogen synthase kinase 3 (GSK3). Oridonin also induced the release of cytochrome c accompanied by the activation of caspase-3 and poly-adenosine diphosphate- ribose polymerase cleavage. In addition, Z-D(OMe)-E(OMe)-V-D(OMe)- FMK (z-DEVD-fmk), an inhibitor of caspases, prevented caspase-3 activation and abrogated oridonin-induced cell death. Finally, oridonin treatment of the HeLa cell line downregulated the expression of the inhibitor of the apoptosis protein.


CONCLUSIONS
Our results showed that oridonin-induced apoptosis involved several molecular pathways. Oridonin may suppress constitutively activated targets of phosphatidylinositol 3-kinase (Akt, FOXO, and GSK3) in the HeLa cell line, inhibiting the proliferation and induction of caspase-dependent apoptosis.
Hu
Hong-zhen
HZ
Department of Gynecology and Obstetrics, Yijishan Hospital,Wannan Medical College, Wuhu 241001, China.
Yang
Yue-bo
YB
Xu
Xiang-dong
XD
Shen
Hong-wei
HW
Shu
Yi-min
YM
Ren
Zi
Z
Li
Xiao-mao
XM
Shen
Hui-ming
HM
Zeng
Hai-tao
HT
D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D024161:Collagen Type XI / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D045786:Diterpenes, Kaurane / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D006367:HeLa Cells; D006801:Humans; D066298:In Vitro Techniques; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors*; D015398:Signal Transduction / Q000187:drug effects; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000473:pathology*
C499319:COL11A2 protein, human; D024161:Collagen Type XI; D045786:Diterpenes, Kaurane; D000081082:Phosphoinositide-3 Kinase Inhibitors; C011959:oridonin; D045304:Cytochromes c; D051057:Proto-Oncogene Proteins c-akt; D020169:Caspases