Objective: To investigate the expression of cyclooxygenase-2(COX-2) and CEA in the tissues adjacent to the tumor within different distances.
Methods: A total of 42 colorectal cancer tissues were collected.The adjacent tissues within 3 cm to the tumor were procured every 1 cm. Normal tissue was also collected. RNA was extracted and the expression of CEA and COX-2 was detected by RT-PCR.
Results: The CEA mRNA levels of the tumor, the tissues of every 1 cm adjacent to the tumor, and the normal tissue were 135.2 ± 23.3, 78.2 ± 17.3, 75.9 ± 16.5, 56.2 ± 10.7, 52.3 ± 12.8, 18.2 ± 7.9, 16.2 ± 6.5, and 16.6 ± 7.0. The levels of COX-2 mRNA in above positions were 134.9 ± 31.1, 79.2 ± 20.2, 77.0 ± 20.5, 62.7 ± 21.9, 58.0 ± 18.1, 21.2 ± 10.3, 18.3 ± 7.6, and 17.1 ± 6.3. These data showed a decreasing trend of CEA and COX-2 as the distance increased from the tumor. The CEA mRNA levels showed positive correlation with the levels of COX-2 mRNA(r=0.725, P<0.01).
Conclusion: CEA and COX-2 may be considered to be used as biomarkers for the study of molecular resection margin of colorectal cancer.