Abstract
Objective
To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87.
Methods
BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN (C124A-PTEN) in vitro. The PTEN expression and the phosphorylation levels of focal adhesion kinase (FAK) and protein kinase B (PKB/Akt) were detected by Western blotting. Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells.
Results
Compared with the control group, PTEN expression in the cells transfected with wild-type PTEN increased to 210%–260%, while the phosphorylation level of FAK and Akt decreased 59% (P < 0.01) and 89% (P < 0.01), respectively. And the anoikis percentage increased from 8.32 ± 0.57% to 37.62 ± 2.12%. In the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the anoikis percentage had obviously changed, although the PTEN expression enhanced remarkably in comparison with the control.
Conclusion
Through its phosphatase activity, tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt, and induce anoikis in human bladder transitional carcinoma cells BIU-87.
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Supported by a grant from the National Natural Science Foundation of China (No. 30271300).
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Guo, Y., Zhang, X., Zhou, S. et al. PTEN induces anoikis through its phosphatase activity in human bladder transitional carcinoma cells BIU-87. Chinese German J Clin Oncol 6, 373–377 (2007). https://doi.org/10.1007/s10330-007-0018-3
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DOI: https://doi.org/10.1007/s10330-007-0018-3