Yang Q Q, Tan H, Fu Z P, Ma Q, Song J L
The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China.
Zhonghua Xue Ye Xue Za Zhi. 2017 Aug 14;38(8):710-715. doi: 10.3760/cma.j.issn.0253-2727.2017.08.012.
To analyze whether heat-shock protein 90 (HSP90) be involved in a permanently abnormal activated JAK/STAT signaling in ATL cells in vitro. The effect of 17-AAG on proliferation of ATL cell lines HUT-102 was assessed using CCK8 at different time points. Cell apoptosis was measured by flow cytometry. The specific proteins HSP90, STAT5, p-STAT5 and JAK3 were detected by Western blotting. Overexpression of HSP90 in HUT-102 cell lines was disclosed (<0.05) , and constitutive activation of JAK3/STAT5 signaling was observed in HTLV-1-infected T-cell lines but not in normal PBMCs; Treatment of ATL cell lines with 17-AAG led to reduced cell proliferation, but there was no significant change in terms of cell proliferation when the concentration of 17-AAG between 2 000-8 000 nmol/L (>0.05) . 17-AAG induced cell apoptosis in different time-points and concentrations. 17-AAG don't affect the expression of JAK3 gene. This study indicated that JAK3 as HSP90 client protein was aberrantly activated in HTLV-1-infected T-cell lines, leading to constitutive activation of p-STAT5 in JAK/STAT signal pathway, which demonstrated that HSP90-inhibitors 17-AAG inhibited the growth of HTLV-1-infected T-cell lines by reducing cell proliferation and inducing cell apoptosis.
分析热休克蛋白90（HSP90）是否参与体外成人T细胞白血病（ATL）细胞中JAK/STAT信号通路的永久性异常激活。在不同时间点使用CCK8评估17-烯丙基氨基-17-去甲氧基格尔德霉素（17-AAG）对ATL细胞系HUT-102增殖的影响。通过流式细胞术检测细胞凋亡。采用蛋白质免疫印迹法检测特异性蛋白HSP90、信号转导和转录激活因子5（STAT5）、磷酸化STAT5（p-STAT5）和Janus激酶3（JAK3）。发现HUT-102细胞系中HSP90过表达（<0.05），在人嗜T淋巴细胞病毒1型（HTLV-1）感染的T细胞系中观察到JAK3/STAT5信号通路的组成性激活，而在正常外周血单个核细胞（PBMCs）中未观察到；用17-AAG处理ATL细胞系导致细胞增殖减少，但当17-AAG浓度在2000-8000 nmol/L之间时，细胞增殖无显著变化（>0.05）。17-AAG在不同时间点和浓度下诱导细胞凋亡。17-AAG不影响JAK3基因的表达。本研究表明，JAK3作为HSP90的客户蛋白在HTLV-1感染的T细胞系中异常激活，导致JAK/STAT信号通路中p-STAT5的组成性激活，这表明HSP90抑制剂17-AAG通过减少细胞增殖和诱导细胞凋亡来抑制HTLV-1感染的T细胞系的生长。
