Relationship between COX-2 and cell cycle-regulatory proteins in patients with esophageal squamous cell carcinoma

AIM To investigate the correlation between cyclooxygenase 2 (COX 2) and cell cycle regulatory proteins in patients with esophageal squamous cell carcinoma (ESCC) METHODS One hundred and two surgically obtained specimens of ESCC were randomly collected All specimens were obtained from patients who had not re caved chemo or radiotherapy prior to surgical resection Twenty eight specimens of normal squamous epithelium served as controls The expression of COX 2, Ki 67, cyclin A and p27 was examined by immunohistochemistry The Pearson test was used to analyze the relationship between groups RESULTS The protein level of COX 2, Ki 67 and cyclin A was significantly higher in ESCC than in normal squamous epithelium (74 7 +/- 61 2 vs 30 2 +/- 43 4, 64 0 +/- 51 6 vs 11 6 +/- 2 3, 44 2 +/- 32 2 vs 11 7 +/- 5 0, respectively, all P < 0 01) In contrast, the protein level of p27 was significantly lower in ESCC than in normal squamous epithelium (182 0 +/- 69 0 vs 266 4 +/- 28 0, P < 0 01) In ESCC, COX 2 expression was correlated with T stage, the score of T1 T2 stage was lower than that of T3 T4 stage (55 0 +/- 42 3 vs 83 0 +/- 66 5, P < 0 05), and Ki 67, cyclin A and p27 expressions were correlated with the tumor differentiation (43 8 +/- 31 7 vs 98 4 +/- 84 8, 32 0 +/- 19 0 vs 54 1 +/- 53 7, 206 2 +/- 61 5 vs 123 5 +/- 68 3, respectively, all P < 0 01) COX 2 expression was positively correlated to Ki 67, cyclin A and negatively correlated to p27 expression in ESCC (r = 0 270 0 233 and 0 311, respectively, all P < 0 05) CONCLUSION The expression of COX 2 is correlated with tumor cell invasion and is closely related to the cell proliferation in patients with ESCC (C) 2010 Baishideng All rights reserved