Expression of p27(Kip1) in gastric cancers and precancerous lesions

Kim, Nam Il; Kang, Hyeock Joo; Jung, Hee Chul; Kim, Sung Ja; Lee, Goo; Suh, Jeong Il; Lee, Chang Woo; Lee, Kyu Chun; Kim, Han Sik; Jang, Tae Jung; Yang, Chang Heon

Abstract

BACKGROUND
The cyclin-dependent kinase inhibitor p27(Kip1) is a negative regulator of cell cycle progression at G1/S transition. Recently, the expression level of p27(Kip1) was decreased in many cancers such as breast, pituitary gland, colon and stomach. We studied the expression of p27(Kip1) in gastric cancers, precancerous lesions and normal gastric tissues and analysed its correlation to clinicopathologic data including tumor differentiation, tumor depth, nodal and distant metastasis in gastric cancers.
METHODS
p27(Kip1) were immunohistochemically stained in the tissue specimens of 62 resected cancers, 110 corresponding adjacent non-neoplastic tissues, 22 gastric adenomas and 10 normal gastric tissues. Adjacent non-neoplastic tissues consisted of 32 chronic gastritis, 29 intestinal metaplasia and 49 transitional mucosa.
RESULTS
Gastric cancers showed significantly decreased expression level of p27(Kip1) when compared with non-neoplastic lesions and adenomas. Labeling index of p27(Kip1) were more decreased in chronic gastritis, intestinal metaplasia and transitional mucosa than in normal mucosa. Early gastric cancers showed significantly decreased expression level of p27(Kip1) when compared with advanced gastric cancers. In gastric cancers, p27(Kip1) labeling index was significantly decreased in diffuse type and presence of nodal metastasis however did not show relationship with distant metastasis and tumor depth of advanced gastric cancers.
CONCLUSION
We suggest that p27(Kip1) may be decreased in the early stage of gastric carcinogenesis and play an important role in the progression and differentiation of gastric cancers. More further studies are thought to be necessary in order to evaluate its prognostic factor in gastric cancers.