Thymidylate synthase and thymidine phosphorylase gene expression as predictive parameters for the efficacy of 5-fluorouracil-based adjuvant chemotherapy for gastric cancer.
OBJECTIVE
To investigate the prognostic role of thymidylate synthase (TS) and thymidine phosphorylase (TP) mRNA levels in T3 or T4 gastric cancer treated with 5-fluorouracil-based adjuvant chemotherapy.


METHODS
Fifty-one patients with T3 or T4 gastric cancer received systemic 5-fluorouracil-based adjuvant chemotherapy, and intratumoral expression of TS and TP in 51 gastric cancer tissue samples was tested by real-time quantitative PCR.


RESULTS
The median disease-free survival (DFS) time was 10.2 mo in the patients. There were no significant differences in DFS between the groups with high and low levels of TP. However, the group with low level of TS had a longer DFS (14.4 mo vs 8.3 mo, P = 0.017). The median overall survival (OS) time was 18.5 mo, and there were significant differences in OS between the groups with high and low levels of TS or TP (for TS, 17.0 mo vs 21.3 mo, P = 0.010; for TP, 16.6 mo vs 22.5 mo, P = 0.009). Moreover, the coupled low expression of these two genes was strongly associated with a longer survival time of patients as compared with that of a single gene.


CONCLUSIONS
Expression of TS and TP mRNA is a useful predictive parameter for the survival of postoperative gastric cancer patients after 5-fluorouracil-based adjuvant chemotherapy.
Hua
Dong
D
Oncology Institute of Wuxi, The Fourth Affiliated Hospital of Suzhou University, 200 Huihe Road, Wuxi 214062, Jiangsu Province, China.
Huang
Zhao-Hui
ZH
Mao
Yong
Y
Deng
Jian-Zhong
JZ
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000201:enzymology* / Q000473:pathology; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D001706:Biopsy; D017024:Chemotherapy, Adjuvant / Q000379:methods; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000201:enzymology* / Q000473:pathology; D013939:Thymidine Phosphorylase / Q000235:genetics / Q000378:metabolism*; D013940:Thymidylate Synthase / Q000235:genetics / Q000378:metabolism*
D000964:Antimetabolites, Antineoplastic; D012333:RNA, Messenger; D013940:Thymidylate Synthase; D013939:Thymidine Phosphorylase; D005472:Fluorouracil