目的：探讨诱导型一氧化氮合酶抑制剂（iNOS）抑制剂对胆管癌细胞生物学行为的影响。方法：不同浓度iNOS抑制剂1400W孵育人胆管癌QBC939细胞24 h后，分别用硝酸还原酶法、MTT比色法检各组细胞中NO浓度与增殖情况，并计算半抑制浓度（IC50）；根据IC50值，选择合适浓度的1400W处理QBC939细胞24 h后，分别用划痕试验、Transwell小室法检测细胞迁移及侵袭情况。以上实验均以未加1400W培养基处理的QBC939细胞为空白对照。结果：与空白对照组比较，各1400W处理组QBC939细胞中NO含量及增殖率均呈浓度依赖性降低（均P<0.05），IC50值为51.24 μmol/L；用50 μmol/L的1400 W处理QBC939细胞24 h后，实验组的细胞划痕愈合率（61.7% vs. 92.3%）和细胞侵袭数（72.7个vs. 128.0个）均较对照组明显降低（均P<0.05）。结论：iNOS抑制剂1400W能抑制胆管癌细胞增殖、迁移和侵袭，其机制可能与NO下游的信号分子变化有关。
Effect of inducible nitric oxide synthase inhibitor on the biological behaviors of cholangiocarcinoma cells
Objective: To investigate the effect of inducible nitric oxide synthase (iNOS) inhibitor on the biological behaviors of cholangiocarcinoma cells. Methods: Human cholangiocarcinoma QBC939 cells were cultured in different concentrations of iNOS inhibitor 1400W for 24 h, and then, the NO contents and proliferation status of each group of cells were determined by nitrate reductase assay and MTT assay respectively, and the half-inhibitory concentration (IC50) was also calculated. After that, QBC939 cells were exposed to an appropriate concentration of 1400W, according to the IC50 value, for 24 h, and then, the cell migration and invasion were detected by wound healing assay and Transwell invasion assay, respectively. QBC939 cells cultured with the medium without 1400W were used as blank control for all experiments. Results: Compared with blank control group, the NO content and proliferation in each 1400W treatment group were significantly reduced, with a concentration-dependent trend, and the IC50 was 51.24 μmol/L. In QBC939 after exposure to 50 μmol/L 1400W, the healing rate of the scratch wound (61.7% vs. 92.3%) and number of invaded cells (72.7 vs. 128.0) were all significantly lower than those in blank control group (both P<0.05). Conclusion: iNOS inhibitor 1400W can suppress the growth, migration and invasion of cholangiocarcinoma cells, the mechanism may be associated with the changes in NO downstream signaling molecules.