Evaluation of Thymidylate Synthase Expression in Prostate Cancer.

Thymidylate synthase (TS), a key enzyme in DNA synthesis, is over-expressed in a variety of cancer cells. 5-Fluorouracil, an anticancer agent clinically used against various cancers, including prostate cancer, inhibits DNA synthesis by binding TS. In this study, we investigated expression of TS in prostate cancer and its prognostic significance. Seventy-five prostatic tissue specimens were obtained from patients who had undergone prostate biopsy for diagnosis of prostate cancer. We analyzed the cancerous tissue specimens for TS expression using immunohistochemistry. TS expression was significantly increased in patients with bone metastasis. No relationship was found between expression of TS and the other clinicopathological findings. Because TS expression could be used as a prognostic parameter in patients with prostate cancer, an accurate prediction of prognosis might help to select patients for more intensive surgical, hormonal, or chemotherapeutic approaches, including 5-fluorouracil. Additional prospective studies are warranted to define the role of TS in selecting patients for adjuvant therapy for prostate cancer.