目 的： 探讨S100A4在低氧条件下对胃癌细胞SGC-7901 迁移及侵袭的作用及其可能的机制。 方法 ：将化学合成的si-S100A4质粒和阴性对照（si-Ctrl）质粒分别转染胃癌细胞株SGC-7901，根据培养条件的不同分为常氧条件（normal，Nor）+si-S100A4组、Nor + si-Ctrl组、低氧条件（hypoxia，Hyp）+si-Ctrl）组、Hyp+si-S100A4组。应用Western blotting检测低氧条件下胃癌SGC-7901细胞中HIF-1及S100A4蛋白的表达变化，检测低氧条件下胃癌细胞中抑制S100A4的表达对细胞中S100A4、β-catenin及TCF-4表达的影响，Transwell小室法分别检测低氧及S100A4对胃癌SGC-7901细胞迁移及侵袭能力的影响。 结果： 低氧条件下：（1）胃癌SGC-7901细胞中HIF-1和S100A4表达水平均明显升高3.12±0.23 vs 1.02±0.05，P<0.01；2.75±0.32 vs 1.05±0.07，P<0.01），且两者变化明显相关（r =0.67，P<0.01）； （2) 胃癌SGC-7901细胞的侵袭及迁移能力增加[(223.31±35.12) vs (131.29±26.40)、(142.27±26.37)个, P<0.05]。干扰低氧条件中S100A4的表达：(1) 明显减少低氧对细胞中β-catenin及TCF-4的促进作用（均P<0.01）；(2) 明显减少低氧对SGC-7901细胞的侵袭及迁移能力的促进作用[(161.37±31.02) vs (88.21±22.42)、(95.36±21.29)个, P<0.05]。 结论： S100A4能够促进胃癌细胞SGC-7901的迁移和侵袭，该作用可能是通过S100A4协同HIF-1通过Wnt/β-catenin通路的调控实现的。

Objective: To explore the effects of S100A4 on the migration and invasion capacity of gastric cancer SGC-7901 cells under hypoxia condition, and to identify the possible mechanism; Methods: The gastric cancer cell line, SGC-7901 was transfected with chemically synthesized si-S100A4 plasmidand si-control plasmid (negative control). Depend-ing on the different culture conditions, SGC-7901 cells were further divided into four groups: normoxia （Nor）+si-S100A4 group, Nor+si-Ctrl group, hypoxia(Hyp) + si-Ctrl group and Hyp+si-S100A4 group. Under the hypoxia condition, the pro-tein expressions of HIF-1 and S100A4 in SGC-7901 cells were detected using the Western blotting assay. The effects of si-S100A4 on the expression of S100A4, β-catenin and TCF-4 upon hypoxia condition were further explored. Moreover, the Transwell assay were conducted to explore the effects of hypoxia and si-S100A4 on the migration and invasion capacity of gastric cancer SGC-7901 cells. Results: Under the hypoxia condition, (1) the expression of HIF-1 and S100A4 in gas-tric cancer SGC-7901 cells were significantly up-regulated (3.12±0.23 vs 1.02±0.05，P<0.01; 2.75±0.32 vs 1.05±0.07, P<0.01), and the expressions were significantly correlated (r=0.67，P<0.01); (2) the migration and invasion capacity of SGC-7901 cells were significantly increased (223.31±35.12 vs 131.29±26.40,142.27±26.37,P<0.05]. Under hypoxia+si-S100A4 condition: (1) the promotion effect of hypoxia on the expressions of β-catenin and TCF-4 was significantly re-duced (all P<0.01); (2) the promotion effect of hypoxia on the migration and invasion ability of SGC-7901 cells was sig-nificantly decreased (161.37±31.02 vs 88.21±22.42、95.36±21.29, P<0.05). Conclusion: S100A4 promoted the migration and invasion capacity of gastric cancer SGC-7901 cells, which was possibly achieved by synergistically working with HIF-1 to regulate Wnt/β-catenin pathway.

重庆市永川区科委项目（No. Ycstc,2013nc8017）