Development of gene therapy on lung cancer with regulation of expression and metabolism of cell cycle regulator p27Kip1

1.通过控制p27Kip1表达水平调控肺癌细胞凋亡和坏死。我们研究了p27Kip1在A549肺腺癌细胞活力中的作用。用腺病毒载体过表达p27Kip1可减少病毒诱导的细胞凋亡，用siRNA表达p27Kip1可诱导细胞凋亡。我们还推测p27Kip1的细胞质部分具有这种抗凋亡的保护能力。调控p27Kip1细胞内定位的机制接下来，我们检查了调控p27Kip1细胞内定位的机制。用S10、T157和T198取代谷氨酸（拟磷），强迫表达p27Kip1 cDNA，诱导其细胞质定位。p27Kip1在肺癌细胞周期调控中的作用。在A549细胞中，我们用腺载体上调p27Kip1的表达水平，用siRNA法下调p27Kip1的表达水平。虽然p27Kip1的过表达降低了细胞周期进程，但去除p27Kip1并不会改变细胞周期状态。p27Kip1在营养缺乏状态下对肺癌细胞活力的影响我们研究了p27Kip1在营养缺乏（氨基酸或葡萄糖）状态下对A549肺腺癌细胞活力的影响。据推测，氨基酸或葡萄糖剥夺导致细胞周期阻滞和细胞死亡，其中一部分被认为是由细胞质p27Kip1的存在所拯救的。

1.Regulation of apoptosis and necrosis of lung cancer cells by controlling the expression level of p27Kip1.We investigated the role of p27Kip1 on cell viability in A549 lung adenocarcinoma cells. p27Kip1 overexpression with adenovirus vector reduced viral-induced apoptosis, and depletion of p27Kip1 with siRNA induced apoptosis. It was also speculated that cytoplasmic portion of p27Kip1 has this protective capacity against apoptosis.2.The mechanism to regulate the intracellular localization of p27Kip1Next, we checked the mechanism to regulate the intracellular localization of p27Kip1. Forced expression of p27Kip1 cDNA with substitution of S10, T157, and T198 to glutamate (phospho-mimetic) induced its cytoplasmic localization.3.The role of p27Kip1 on cell cycle regulation in lung cancer cells.We regulated p27Kip1 exptession level upward with adenovector and downward with the siRNA method in A549 cells. Although overexpression of p27Kip1 reduced cell cycle progression, its removal did not change cell cycle status.4.The role of p27Kip1 on viability under the state of nutritional deficiency in lung cancer cellsWe investigated the role of p27Kip1 on viability under the state of nutritional deficiency (amino acid or glucose) in A549 lung adenocarcinoma cells. It was supposed that amino acid or glucose deprivation induced cell cycle arrest and cell death, part of which is thought to be rescued by the existence of cytoplasmic p27Kip1.