Apoptosis activated in fibrosarcoma growth

一种蛋白质独立的纤维瘤，Gc-4PF，在一种无蛋白质介质中生长。双重时间与血清依赖性的父克隆物（Gc-4SD）相似，在脂肪钙血清的存在中被归类。Gc-4PF细胞的无蛋白质培养通常激活凋亡表型（一种第三种全细胞种群），包括典型形态学，Hoechst 33342天高提取率，以及DNA到大片段的清除，如先前在蛋白质依赖的Gc-4SD细胞中观察到的。Gc-4 SD cells arrested in the G-D20/G-D21/G-D2 phase in response to the Protein-free condition。In contrast，Gc-4 PF cells did not reach G-D20-D2/G-D21-D2 arrest in the protein-free condition ; instead the Durations of both G-D20-D2/G-D21-D2 and G-D22-D2 phases were markedly reduced。对一个细胞的周期持续时间的估计被揭示，该细胞分裂周期已加速至1.7-折叠。然后，增长动力学可以通过细胞分裂率和适应性细胞损失来量化地核实。无蛋白质培养结果在两种细胞类型中的c-myc蛋白质缓慢调节时，当P34 d1cdc 2 D1的下行调节时，Gc-4SD细胞中明显明显可见，在Gc-4PF细胞中已禁用。有趣的是，尽管P53的表达在Gc-4SD细胞中不受响应于无蛋白质条件的影响，但抑制剂基因产品表达在Gc-4PF细胞中受到抑制的标记。从这些结果Gc-4PF细胞可能具有通过缩短细胞分区的能力来实现加速细胞分区，以保持细胞周期持续时间在响应内在凋亡激活中的良好增长率，至少在部分中，p53表达的抑制作为一个成功的转移P34 D1cdc 2 D1。

A protein-independent fibrosarcoma, Gc-4 PF, grows exponentially in a protein-free medium. The doubling time was similar to that of the serum-dependent parental clone, Gc-4 SD cultivated in the presence of fetal calf serum. The protein-free cultivation of Gc-4 PF cells concomitantly activates apoptotic phenotypes (one third total cell population), including typical morphology, high uptake of Hoechst 33342 dye, and cleavage of DNA to large fragments, as observed in protein-deprived Gc-4 SD cell previously. Gc-4 SD cells arrested in the GィイD20ィエD2/GィイD21ィエD2 phase in response to the protein-free condition. In contrast, Gc-4 PF cells did not reach GィイD20ィエD2/GィイD21ィエD2 arrest in the protein-free condition ; instead the durations of both GィイD20ィエD2/GィイD21ィエD2 and GィイD22ィエD2 phases were markedly reduced. The estimation of one cell cycle duration revealed that the cell division cycle was accelerated to 1.7 -fold. Then the growth kinetics was able to be verified quantitatively by both the cell division rate and apoptotic cell loss. Protein-free cultivation resulted in slight down-regulation of c-myc protein in both cell types, while the down-regulation of P34ィイD1cdc2ィエD1, shown clearly in Gc-4 SD cells, was avoided in Gc-4 PF cells. Interestingly, while the expression of p53 was not affected in Gc-4 SD cells in response to the protein-free condition, the suppressor gene product expression was suppressed markedly in Gc-4 PF cells. From these results Gc-4 PF cells may have acquired an ability to accelerate cell division by shortening the cell cycle duration to maintain a proper growth rate in response to intrinsic apoptosis activation with, at least in part, a suppression of p53 expression as well as an escape of down-regulation of P34ィイD1cdc2ィエD1.