Endogenous gamma-interferon activates thymidine phosphorylase in colorectal cancer tissue.
We measured neopterin (NPT), an indirect marker of gamma (gamma)-interferon, and the activity of thymidine phosphorylase (dThdPase) in the advancing front of colorectal carcinoma and in normal mucosa. Cancer showed a higher concentration of NPT than normal mucosa and also showed significantly higher (p < 0.0001) dThdPase activity than normal mucosa. There was a strong correlation between NPT concentration and dThdPase activity in cancerous and normal mucosa. These results suggest that endogenous gamma-interferon could activate dThdPase activity, which is essential to nucleic acid metabolism because it regulates the availability of thymidine.
Iwagaki
H
H
First Department of Surgery, Okayama University Medical School, Japan.
Hizuta
A
A
Mori
K
K
Yoshino
T
T
Kawahara
K
K
Tanaka
N
N
Orita
K
K
D000230:Adenocarcinoma / Q000201:enzymology*; D001708:Biopterins / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000201:enzymology*; D004789:Enzyme Activation / Q000502:physiology; D006801:Humans; D007371:Interferon-gamma / Q000502:physiology*; D007413:Intestinal Mucosa / Q000201:enzymology; D009363:Neoplasm Proteins / Q000378:metabolism; D019798:Neopterin; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D013939:Thymidine Phosphorylase / Q000378:metabolism*
D009363:Neoplasm Proteins; D010982:Platelet-Derived Growth Factor; D001708:Biopterins; D019798:Neopterin; D007371:Interferon-gamma; D013939:Thymidine Phosphorylase