PURPOSE: To identify the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) during gamma-ionizing radiation (gamma-IR) treatment for non-small-cell lung cancer cells. METHODS AND MATERIALS: Wild-type PTEN or mutant forms of PTEN plasmids were transfected to construct stable transfectants of the NCI-H1299 non-small-cell lung cancer cell line. Combined effects of PTEN expression and IR treatment were tested using immunoblot, clonogenic, and cell-counting assays. Related signaling pathways were studied with immunoblot and kinase assays. RESULTS: At steady state, stable transfectants showed almost the same proliferation rate but had different AKT phosphorylation patterns. When treated with gamma-IR, wild-type PTEN transfectants showed higher levels of cell death compared with mock vector or mutant transfectants, and showed increased G(2)/M cell-cycle arrest accompanied by p21 induction and CDK1 inactivation. NCI-H1299 cells were treated with phosphosinositide-3 kinase (PI3K)/AKT pathway inhibitor (LY29002), resulting in reduced AKT phosphorylation levels. Treatment of NCI-H1299 cells with LY29002 and gamma-IR resulted in increased cell-cycle arrest and p21 induction. Endogenous wild-type PTEN-containing NCI-H460 cells were treated with PTEN-specific siRNA and then irradiated with gamma-IR: however reduced PTEN levels did not induce cell-cycle arrest or p21 expression. CONCLUSIONS: Taken together, these findings indicate that PTEN may modulate cell death or the cell cycle via AKT inactivation by PTEN and gamma-IR treatment. We also propose that a PTEN-PI3K/AKT-p21-CDK1 pathway could regulate cell death and the cell cycle by gamma-IR treatment.
PURPOSE: To identify the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) during gamma-ionizing radiation (gamma-IR) treatment for non-small-cell lung cancer cells. METHODS AND MATERIALS: Wild-type PTEN or mutant forms of PTEN plasmids were transfected to construct stable transfectants of the NCI-H1299 non-small-cell lung cancer cell line. Combined effects of PTEN expression and IR treatment were tested using immunoblot, clonogenic, and cell-counting assays. Related signaling pathways were studied with immunoblot and kinase assays. RESULTS: At steady state, stable transfectants showed almost the same proliferation rate but had different AKT phosphorylation patterns. When treated with gamma-IR, wild-type PTEN transfectants showed higher levels of cell death compared with mock vector or mutant transfectants, and showed increased G(2)/M cell-cycle arrest accompanied by p21 induction and CDK1 inactivation. NCI-H1299 cells were treated with phosphosinositide-3 kinase (PI3K)/AKT pathway inhibitor (LY29002), resulting in reduced AKT phosphorylation levels. Treatment of NCI-H1299 cells with LY29002 and gamma-IR resulted in increased cell-cycle arrest and p21 induction. Endogenous wild-type PTEN-containing NCI-H460 cells were treated with PTEN-specific siRNA and then irradiated with gamma-IR: however reduced PTEN levels did not induce cell-cycle arrest or p21 expression. CONCLUSIONS: Taken together, these findings indicate that PTEN may modulate cell death or the cell cycle via AKT inactivation by PTEN and gamma-IR treatment. We also propose that a PTEN-PI3K/AKT-p21-CDK1 pathway could regulate cell death and the cell cycle by gamma-IR treatment.
Authors: Michael Christensen; Abdo J Najy; Michael Snyder; Lisa S Movilla; Hyeong-Reh Choi Kim Journal: Int J Radiat Oncol Biol Phys Date: 2014-01-01 Impact factor: 7.038
Authors: Zhang Chun-Zhi; Han Lei; Zhang An-Ling; Fu Yan-Chao; Yue Xiao; Wang Guang-Xiu; Jia Zhi-Fan; Pu Pei-Yu; Zhang Qing-Yu; Kang Chun-Sheng Journal: BMC Cancer Date: 2010-07-12 Impact factor: 4.430
Authors: Lin Zheng; Yuqin Zhang; Yan Liu; Min Zhou; Yanxia Lu; Li Yuan; Chao Zhang; Min Hong; Shuang Wang; Xuenong Li Journal: J Transl Med Date: 2015-08-04 Impact factor: 5.531