Published online Dec 15, 1997. doi: 10.3748/wjg.v3.i4.262
Revised: May 25, 1997
Accepted: June 28, 1997
Published online: December 15, 1997
AIM: To determine whether expression of the tumor suppressors p16 and Rb is altered in gastric carcinoma.
METHODS: Mucosal biopsies were endoscopically obtained from patients with superficial gastritis (n = 12), atrophic gastritis (n = 15), atypical hyperplasia (n = 20) and gastric cancer (n = 40). Upon obtainment, all samples were immediately fixed with 10% buffered formalin, embedded in paraffin, and sectioned serially. Protein expression of p16 and Rb was detected by immunohistochemistry (ABC method).
RESULTS: The gastric epithelium samples showed various degrees of nuclear immunostaining for p16 and Rb according to the different stage of lesion. Progressive pathology of the lesions was associated with a decreasing trend in positive immunostaining for p16 protein (83.3% > 73.3% > 30.0% > 27.5%) but an increasing trend for Rb protein (25.0% > 46.7% > 60.0% > 67.5%). A negative correlation was found between these two parameters and gastric cancer. Correlation analysis of the 40 cases of gastric cancer identified a negative correlation for 20 of the cases. When positive (n = 9) and negative tissues (n = 11) were compared, a statistically significant difference was found (50.0%, 22.5%, 27.5%) (P < 0.05).
CONCLUSION: Abnormal expression of p16 and Rb may play an important role in gastric carcinogenesis.