[Expression of cell cycle-regulatory proteins in squamous cell carcinoma of the esophagus].

BACKGROUND & OBJECTIVE: Tumor cell cycle analysis has indicated that tumors with a higher proliferation rate showed more aggressive clinical behavior. Cell cycle-regulatory proteins Ki-67, cyclin A, and p27 are associated with cell proliferation. The objective of this study was to observe the character of expression of cell cycle-regulatory proteins Ki-67, cyclin A, and p27 in esophageal carcinoma and to clarify the relationship between clinicopathologic and these proteins. METHODS: Immunohistochemistry for Ki-67, cyclin A, and p27 were carried out. Ki-67 and cyclin A staining index (SI), and p27 labeling index were examined and detailed pathologic examinations were conducted on tumors from 60 patients (48 males and 12 females with surgically resected esophageal squamous cell carcinoma). RESULTS: Ki-67, cyclin A, and p27 immunostaining were all confined to the nuclei in both neoplastic and non-neoplastic cells. The staining indexes(SIs) of Ki-67 and cyclin A, were significantly higher in poorly differentiated squamous cell carcinoma (SCC,27.2+/-4.9;15.4+/-5.3) than in well differentiated SCC(20.6+/-6.3;11.3+/-6.4,P< 0.05). The p27 positive immunostaining in the nuclei in well-differentiated SCC(36%)were higher than that in the other tumor types (29%;18%), but there was no significance(P< 0.25,P >0.05). CONCLUSION: The expression levels of Ki-67, cyclin A, and p27 may suggest the proliferative activity of cancer cells in Chinese patient with SCC of esophagus. The cell cycle-regulatory proteins Ki-67 and cyclin A over-expression correlates with poor SCC differentiation in patients with esophageal carcinoma.