Knockdown of Wip1 Enhances Sensitivity to Radiation in HeLa Cells Through Activation of p38 MAPK.
The objectives of the study were to investigate the functional role and potential mechanism of wild-type p53-induced phosphatase (Wip1) in cervical cancer cell line HeLa cells, along with the effect of knockdown of Wip1 in combination with γ-irradiation on the HeLa cells. Expression of Wip1 was silenced or overexpressed. After transfection, cell viability was determined. Moreover, γ-irradiation and SB203580 were performed to explore the effect of colony formation and cell apoptosis. Likewise, protein expression levels of p38, p-p38, p53, and p-p53 were assessed in the presence or not of SB203580 and overexpression of Wip1. Both the mRNA and protein levels of Wip1 were significantly decreased by transfection with Wip1-specific small interfering RNA (siRNA) but were significantly increased by transfection with pcDNA3.1-Wip1. Knockdown of Wip1 significantly decreased cell growth and colony formation ability and increased apoptotic rate. Additionally, better results were obtained by knockdown of Wip1 in combination with γ-irradiation. The protein expression levels of p-p38 (p < 0.05), p53 (p < 0.01), and p-p53 (p < 0.05) were all significantly increased by knockdown of Wip1. However, application of SB203580 reversed the effects. Our study confirms the important roles of Wip1 in cervical cancer. Knockdown of Wip1 enhances sensitivity to radiation in HeLa cells by inhibiting cell proliferation and inducing apoptosis through activation of p38 MAPK.
Department of Radiotherapy, 2nd Hospital Affiliated to Jilin University, Jilin University, Changchun, Jilin, China.
Hong-Yong
HY
Wang
Zhong-Shan
ZS
Liu
Ling
L
Qiu
Jie
J
Guo
Yun-Feng
YF
Li
Jun
J
Zhang
Tie-Jun
TJ
Wang
Xiao-Dong
XD
Liu
D017209:Apoptosis / Q000528:radiation effects; D049109:Cell Proliferation / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D015536:Down-Regulation; D004789:Enzyme Activation; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006367:HeLa Cells; D006801:Humans; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D000071636:Protein Phosphatase 2C; D034622:RNA Interference; D011836:Radiation Tolerance; D015398:Signal Transduction / Q000528:radiation effects; D013997:Time Factors; D014162:Transfection; D002583:Uterine Cervical Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
D048051:p38 Mitogen-Activated Protein Kinases; C000607458:PPM1D protein, human; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C