TYMS and gastric cancer: In gastric cancer, the prognostic significance of TS, MRP1, and P-gp expression has been showing conflicting results (Endo et al, 1996a; Monden et al, 1997; Kuniyasu et al, 1998; Takebayashi et al; 1998; Suda et al, 1999; Choi et al, 2001).