Thymidine kinase (TK), the key enzyme in the pyrimidine salvage pathway, and its isozymes were examined in tissues and sera of patients with or without colorectal cancer. Colorectal TK isozymes were separated into two types by DEAE-cellulose column chromatography, i.e., cytosolic-fetal type (peak A) that was not affected by deoxycytidine triphosphate (dCTP), and mitochondrial-adult type (peak B) affected by dCTP. The activity of cytosolic TK isozyme (peak A) in colorectal cancer was increased to 6-fold that in normal colon mucosa. On the other hand, serum TK activities were significantly high in patients in clinical stage V and with recurrence or distant metastasis. The measurement of serum TK activity may be valuable to determine the clinical stages in the patients with solid tumors as well as neoplastic blood diseases.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Tumor Marker Oncology|
|State||Published - Dec 1 1989|
ASJC Scopus subject areas
- Cancer Research