[Analysis of the protein expression and gene amplification of HER2 in gastric cancer].

Objective: To explore the clinical significance of protein expression and gene amplification of HER2 in gastric cancer.
Methods: Immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH) method were used to detect protein expression and gene amplification of HER2 in 80 specimens of gastric cancer patients.
Results: Protein expression of HER2 was negative in 51 cases, (+) in 12 cases, (++) in 12 cases, (+++) in 5 cases, and the positive expression rate was 21.3% (17/80). Seven (8.8%) cases had gene amplification of HER2, including gene critical amplification in 3 (3.8%) cases. The result of IHC was positively correlated with CISH (P<0.05), and the coincidence rate was 85.0% (68/80). HER2 positive expression rate was higher in the gastroesophageal junction carcinoma, poorly differentiated and stage III-IIII gastric cancer (all P<0.05).
Conclusion: The gastric cancer tissue has high positive rate of protein expression and gene amplification of HER2, which is closely correlated to the development of gastric cancer.