Effect of long intergenic noncoding RNA-p21 knockdown on radiosensitivity of hypoxic tumor cells
10.3760/cma.j.issn.0254-5098.2016.01.003
- VernacularTitle:敲低长链基因间非编码RNA-p21对乏氧肿瘤细胞放射敏感性的影响
- Author:
Yueming SHEN
;
Wei YANG
- Publication Type:Journal Article
- Keywords:
lincRNA-p21;
Hypoxia;
Cell cycle arrest;
Cell apoptosis;
Radiosensitivity
- From:
Chinese Journal of Radiological Medicine and Protection
2016;36(1):19-23
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect and mechanisms of lincRNA-p21 knockdown on radiosensitivity of hypoxic tumor cells.Methods The expression of lincRNA-p21 in SMMC7721 and U251 MG cells after hypoxia treatment were detected by QRT-PCR.Lentivirus vector carrying lincRNA-p21 siRNA or scrambled oligos were constructed.SMMC7721 and U251MG cells with stable integration of lincRNA-p21 siRNA or scrambled sequence were generated through lentiviral-mediated gene transfer.Cell cycle and apoptosis of hypoxic tumor cells were analyzed by flow cytometry.Radiosensitivity of hypoxic tumor cells were measured by cloning formation assay.The expressions of HIF-1α and GLUT1 protein were detected by Western blot.Results Under hypoxia condition (1％ O2) for 24 and 48 h, lincRNA-p21 strongly increased (t =5.13, 7.49, 8.90, 10.11, P ＜ 0.05) in SMMC7721 and U251MG cells in a timedependent manner, but this increase was suppressed in the SMMC7721 and U251MG cells with stable integration of lincRNA-p21 siRNA (t =144.81, 334.32, P ＜ 0.05).When SMMC7721 and U251MG cells were cultured under hypoxia condition (1％ O2) for 48 h, knockdown of lincRNA-p21 induced G2/M phase arrest (t =7.05, 10.18, P ＜ 0.05) and apoptosis (t =42.27, 24.79, P ＜ 0.05), reduced the expressions of HIF-1α and GLUT1 protein, and enhanced radiosensitivity with a radiosensitization ratio of 1.23 and 1.31, respectively.Conclusions Hypoxia treatment elevate the expression of lincRNA-p21.Knockdown of lincRNA-p21 enhance radiosensitivity of hypoxic tumor cells accompanied with G2/M phase arrest, apoptosis induction and the decrease of HIF-1α protein expression.
