Abstract: Objective To explore the effect of hypoxia on migration and invasion of hypoxia-inducing reagent to mimic tumor hypoxic microenvironment. mRNA and protein levels of HIF-1α, E-cadherin and MMP-2 at different hypoxic culture phases were detected by semi-quantitative RT-PCR and immunohistochemistrym, respectively. After being treated with rapamycin combined with hypoxia, the protein expression of HIF-1α, E-cadherin and MMP-2 were assayed by western blot. The effect of rapamycin combined with hypoxia on migration and invasion were tested by cell scratch assay and transwell chambers. Results Under hypoxia, mRNA level of HIF-1α had no significant change, while its protein level increased obviously; mRNA and protein levels of E-cadherin were down-regulated, but the mRNA and protein levels of MMP-2 were up- regulated. Under hypoxia, rapamycin inhibited the expression of HIF-1αand MMP-2, but E-cadherin was up-regulated. The migration and the number of invading cells decreased (P<0.05) after the treatment of rapamycin under hypoxia. Conclusion Hypoxia can increase protein level of HIF-1α in esophageal carcinoma, which promote migration and invasion possibly through down-regulating E-cadherin and up-regulating MMP-2 .

Key words: hypoxia inducible factor-1α, esophageal carcinoma, E-cadherin, MMP-2