Background and objective: The results of published data on the effect of CD40 signal related to cancer cell sensitivity to chemotherapy are inconclusive. The aim of this study is to investigate the effect of soluble CD40 ligand (sCD40L) combined with vinorelbine on lung adenocarcinoma cell line A549.
Methods: Lung adenocarcinoma A549 cells were chosen as target cells and CD40 signal was stimulated by sCD40L. MTT assay and flow cytometry were used to determine the changes of cell proliferation, cell cycle and apoptosis of A549 cells treated by vinorelbine after CD40 was stimulated. The activity of Caspase-3 was measured using Caspase-3 cellular activity assay kit plus.
Results: After CD40 stimulation, an increase of inhibition on CD40 positive cell line A549 proliferation was confirmed when vinorelbine was added (P < 0.05). However, no significant changes were shown in apoptosis and cell cycle (P > 0.05). On the other hand, the activity of Caspase-3 was substantially decreased (P < 0.05).
Conclusions: Stimulation of CD40 can increase lung adenocarcinoma cell line A549 sensitivity to vinorelbine, which may be through a non-apoptosis, Caspase independent mechanism, and not associated with the inhibition of cell cycle.
背景与目的: CD40信号对肿瘤细胞化疗敏感性的影响存在争议。本研究旨在观察可溶性CD40配体（sCD40L）联合长春瑞滨对肺腺癌A549细胞的作用。
方法: 以sCD40L处理A549细胞，MTT法和流式细胞仪检测CD40激发前后长春瑞滨作用下A549细胞的生长、细胞周期及凋亡率等生物学行为的变化，同时用Caspase-3检测试剂盒分析Caspase-3活性的改变。
结果: sCD40L对CD40分子的激发可增强长春瑞滨对表达CD40肺癌细胞株A549增殖的抑制率（P < 0.05），但并不显著影响细胞周期时相和细胞凋亡率（P > 0.05），Caspase-3活性反而显著下降（P < 0.05）。
结论: 以sCD40L激发CD40信号可增强肺腺癌细胞A549对长春瑞滨的敏感性，可能通过非凋亡的、Cas-pase非依赖性的机制，且可能与抑制细胞周期进程无关。