JIP影响鼻咽癌细胞增殖和凋亡的生物学效应研究

背景与目的：研究表明LMP1激活c-Jun N末端激酶（c-Jun N-ternimal kinase,JNK)介导的信号途径在促进鼻咽癌的发生发展有重要作用,并且发现JNK相互作用蛋白（JNK interacting protein,JIP)在鼻咽癌细胞中能够有效抑制JNK信号途径。本实验在此基础上进一步研究JIP对鼻咽癌细胞增殖和凋亡生物学效应的影响。方法：采用MTT法观察不同剂量的JIP及相同剂量JIP作用不同时间后鼻咽癌细胞生长情况;并用集落形成率确定单个鼻咽癌细胞的增殖能力;同时用流式细胞术分析JIP作用不同时间后鼻咽癌细胞生长情况;并用集落形成率确定单个鼻咽癌细胞的增殖能力;同时用流式细胞术分析JIP作用前后细胞周期时相的变化;最后通过流式细胞术检测JIP作用后鼻咽癌细胞凋亡百分率的改变。结果：（1）随着转染JIP量的增加,细胞的存活率逐渐下降,存在剂量依赖效应;1μg/ml JIP作用24、48、72h后,细胞存活率分别为77．8％、59．2％、61．8％。（2）转染JIP后鼻咽癌细胞形成的集落明显减少,且集落体积变小。（3）转染JIP使鼻咽癌细胞周期G0／G1期细胞百分率由66．24％上升到71．89％,S期细胞百分率由25．87％下降到19．96％。（4）与对照组相比,转染JIP后细胞的24h 凋亡百分率由1．25％上升到8．25％,上升约6．6倍,48h由1．04％上升到31．45％,上升约30倍。结论：JIP能够有效抑制鼻咽癌细胞生长增殖,引起鼻咽癌细胞周期G1／S期延长,并明显促进鼻咽癌细胞凋亡,提示JIP是治疗鼻咽癌潜在的分子药物。

Effect of JIP on the proliferation and apoptosis of nasopharyngeal carcinoma cells

Background & Objective: Previous studies showed that JNK signaling pathway activated by LMP1 plays an important role in carcinogenesis of nasopharyngeal carcinoma (NPC). JNK interacting protein (JIP) can inhibit JNK signaling pathway in NPC cell. This study was designed to elucidate the effect of JIP on the proliferation and apoptosis of NPC cells. Methods: After treatment with JIP at different concentrations and time points, the number of proliferating cells were determined by MTT assay; the ability of proliferation of NPC cells was measured by the rate of cloning formation; cell cycle and the apoptotic rate of NPC cells was assayed by flow cytometry. Results: 1MTT assay showed that cell proliferation was significantly inhibited by JIP in a dose and time dependent manner.After treatment with JIP for 24,48,and 72 hours, the rate of survival cells were 77.8%,59.2%, and 61.8%, respectively. 2The number and volume of colonies were decreased after transfection with JIP. 3The number of cells in S phase was decreased from 25.87% to 19.96%, and the number of cells in G0/G1 phase was elevated from 66.24% to 71.89% after treatment with JIP. 4In contrast to the control group,the 24 hours apoptotic rate was elevated from 1.25% to 8.25%(about 6.6 times);the 48 hours apoptotic rate was elevated from 1.04% to 31.45%(about 30 times).Conclusions: The results demonstrated that JIP inhibit the growth of nasopharyngeal carcinoma through arresting the cell cycle at G1/S checkpoint and triggering the apoptosis of cells. Data suggest that JIP is a potent molecular drug for the treatmeat of the patients with nasopharyngeal carcinoma.