TY - JOUR
T1 - Thymidylate synthase gene polymorphism affects the response to preoperative 5-fluorouracil chemoradiation therapy in patients with rectal cancer
AU - Hur, Hyuk
AU - Kang, Jeonghyun
AU - Kim, Nam Kyu
AU - Min, Byung Soh
AU - Lee, Kang Young
AU - Shin, Sang Joon
AU - Keum, Ki Chang
AU - Choi, Junjeong
AU - Kim, Hoguen
AU - Choi, Sung Ho
AU - Lee, Mi Young
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2011/11/1
Y1 - 2011/11/1
N2 - Purpose: This study aims to correlate thymidylate synthase (TS) gene polymorphisms with the tumor response to preoperative 5-fluorouracil (5-FU)-based chemoradiation therapy (CRT) in patients with rectal cancer. Methods and Materials: Forty-four patients with rectal cancer treated with 5-FU-based preoperative CRT were prospectively enrolled in this study. Thymidylate synthase expression and TS gene polymorphisms were evaluated in tumor obtained before preoperative CRT and were correlated with the pathologic response, as assessed by histopathologic staging (pTNM) and tumor regression grade. Results: Patients exhibited 2R/3R and 3R/3R tandem repeat polymorphisms in the TS gene. With regard to TS expression in these genotypes, 2R/3RC and 3RC/3RC were defined as the low-expression group and 2R/3RG, 3RC/3RG, and 3RG/3RG as the high-expression group. There was no significant correlation between TS expression and tumor response. There was no significant difference in the tumor response between patients homozygous for 3R/3R and patients heterozygous for 2R/3R. However, 13 of 14 patients in the low-expression group with a G>C single-nucleotide polymorphism (SNP) (2R/3RC [n = 5] or 3RC/3RC [n = 9]) exhibited a significantly greater tumor downstaging rate, as compared with only 12 of 30 patients in the high-expression group without the SNP (2R/3RG [n = 10], 3RC/3RG [n = 9], or 3RG/3RG [n = 11]) (p = 0.001). The nodal downstaging rate was also significantly greater in this low-expression group, as compared with the high-expression group (12 of 14 vs. 14 of 30, p = 0.014). However, there was no significant difference in the tumor regression grade between these groups. Conclusions: This study suggests that SNPs within the TS enhancer region affect the tumor response to preoperative 5-FU-based CRT in rectal cancer.
AB - Purpose: This study aims to correlate thymidylate synthase (TS) gene polymorphisms with the tumor response to preoperative 5-fluorouracil (5-FU)-based chemoradiation therapy (CRT) in patients with rectal cancer. Methods and Materials: Forty-four patients with rectal cancer treated with 5-FU-based preoperative CRT were prospectively enrolled in this study. Thymidylate synthase expression and TS gene polymorphisms were evaluated in tumor obtained before preoperative CRT and were correlated with the pathologic response, as assessed by histopathologic staging (pTNM) and tumor regression grade. Results: Patients exhibited 2R/3R and 3R/3R tandem repeat polymorphisms in the TS gene. With regard to TS expression in these genotypes, 2R/3RC and 3RC/3RC were defined as the low-expression group and 2R/3RG, 3RC/3RG, and 3RG/3RG as the high-expression group. There was no significant correlation between TS expression and tumor response. There was no significant difference in the tumor response between patients homozygous for 3R/3R and patients heterozygous for 2R/3R. However, 13 of 14 patients in the low-expression group with a G>C single-nucleotide polymorphism (SNP) (2R/3RC [n = 5] or 3RC/3RC [n = 9]) exhibited a significantly greater tumor downstaging rate, as compared with only 12 of 30 patients in the high-expression group without the SNP (2R/3RG [n = 10], 3RC/3RG [n = 9], or 3RG/3RG [n = 11]) (p = 0.001). The nodal downstaging rate was also significantly greater in this low-expression group, as compared with the high-expression group (12 of 14 vs. 14 of 30, p = 0.014). However, there was no significant difference in the tumor regression grade between these groups. Conclusions: This study suggests that SNPs within the TS enhancer region affect the tumor response to preoperative 5-FU-based CRT in rectal cancer.
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U2 - 10.1016/j.ijrobp.2010.06.049
DO - 10.1016/j.ijrobp.2010.06.049
M3 - Article
C2 - 20932673
AN - SCOPUS:79959692417
VL - 81
SP - 669
EP - 676
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
SN - 0360-3016
IS - 3
ER -