The Relation between Microsatellite Instability and the Thymidylate Synthase Expression in Gastric Cancer.
10.5230/jkgca.2008.8.4.169
- Author:
Hyun Seok KO
1
;
Chang Wook AHN
;
Hae Youn KANG
;
Kwang Il KIM
;
Sung Pyo HONG
;
Dae Ho AHN
Author Information
1. Department of Surgery, College of Medicine, Pochon CHA University, Seongnam, Korea. dhahn@cha.ac.kr
- Publication Type:Original Article
- Keywords:
Microsatellite instability;
Thymidylate synthase;
Gastric cancer
- MeSH:
Animals;
Chemotherapy, Adjuvant;
Colorectal Neoplasms;
Fluorouracil;
Gastrectomy;
Humans;
Immunohistochemistry;
Mice;
Microsatellite Instability;
Microsatellite Repeats;
Polymerase Chain Reaction;
Stomach Neoplasms;
Succinimides;
Thymidylate Synthase
- From:Journal of the Korean Gastric Cancer Association
2008;8(4):169-175
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: The main target of 5-fluorouracil (5-FU) is thymidylate synthase (TS). A high TS expression has been identified as promoting resistance to 5-FU. For colorectal cancers, the response to 5-FU based adjuvant chemotherapy is different according to the microsatellite instability (MSI) status. The reports on the relationship between MSI and the TS expression in colorectal cancer have been inconsistent. No data is available for gastric cancer regarding the relationship between MSI and the TS expression. Therefore, we studied the relationship between MSI and the TS expression in gastric cancer. MATERIALS AND METHODS: Ninety-nine consecutive patients who underwent radical gastrectomy for gastric cancer from January 2004 to May 2006 at Bundang CHA hospital were studied. MSI was assessed for five markers (BAT25, BAT26, D2S123, D5S346, and D17S250) by PCR and with using an ABI prism 3100 Genetic analyzer. The TS expression was analyzed by immunohistochemistry with using mouse anti-thymidylate synthase monoclonal antibody to the TS 106 clone. RESULTS: Out of the ninety-nine patients, MSS/MSI-L was detected in 92 (92.1%) cases and 7 cases (7.1%) were MSI-H. A negative TS expression was found in 46 (46.5%) cases, a low TS expression was found in 33 (33.3%) and a high TS expression was found in 20 (20.2%). Out of 92 MSS/MSI-L patients, the number of patients with negative, low and high TS expressions were 46 (50%), 30 (32.6%) and 16 (17.4%), respectively. Out of the 7 MSI-H patients, the number of patients with negative, low and high TS expressions were 0 (0%), 3 (42.9%) and 4 (57.1%), respectively. The relationship between MSI-H and a high TS expression was statistically significant. CONCLUSION: Gastric cancer with MSI-H showed higher levels of a TS expression compared to the gastric cancer with MSS/MSI-L.
