Hie expression of hypoxia-inducible factor- 1a ( HIF-1a) is one of the important factors that cause most solid tumors rapid growth in hypoxic microenvironment, HIF-1a plays an important role in tumor angjogenesis, cell proliferation, metastasis and apoptosis. Similarly, HIF-1a also plays important biological roles in the occurrence and progression of digestive system carcinomas, such as esophagus cancer, stomach cancer, colon cancer, liver cancer and pancreatic cancer. HIF-1a can be used as one of the important molecular markers in prevention and treatment of gastrointestinal cancers.