Inhibition of WIP1 in A549 cells enhances the sensitivity of cells to arsenic treatment
Luo, Q.; Gu, S.; Zhang, Z.
Wei Sheng Yan Jiu 46(3): 389-395
2017
ISSN/ISBN: 1000-8020 PMID: 29903248 Document Number: 692118
To explore if inhibiting the expression of wild-type p53-induced phosphatase 1( WIP1) could enhance the sensitivity of A549 cells to arsenic. To inhibit expression of WIP1, WIP1 siRNA was transferred into A549 cells by using Lipofectamine 2000. Then the protein expression levels of P53 phosphorylation proteins and their downstream effectors were detected by western-blot analysis. Cell apoptosis were assessed by Annexin V-FITC stain assay. The sensitivity of transferred cells to arsenic was detected by using MTT assay. The mRNA and protein expression level of WIP1 were all decreased by 70 % in A549 cells transferred with WIP1 siRNA. Western-blot analysis indicated that P53 phosphorylation process was much accelerated in WIP1-inhibited cells after arsenic treatment. For example, compared to control cells, an significant decrease in P53 ser15 expression and an increase in P53 ser46 expression was found in WIP1-inhibited cells when treated with As_2O_3( 5-40 μmol/L). In addition, compared to control group, the expression of P21 decreased whereas PUMA increased in WIP1-inhibited cells when treated with As_2O_3( 10-40 μmol/L). Cell viability of WIP1-inhibited cells after As_2O_3 treatment( 5-40 μmol/L) was significantly higher than that of the control group, which may be due to a high apoptosis rate in WIP1-inhibited cells. WIP1 could be used as a new target in arsenic-base anticancer therapies.