Cyclooxygenase-2 and thromboxane synthase in non-endocrine and endocrine tumors: a review.
Prostaglandins (PG) are members of a large group of hormonally active fatty acids derived from free fatty acids. They are formed from arachidonic acid-the major PG precursor. Cyclooxygenase (COX)-1 and -2 are the rate-limiting steps in PG synthesis. COX-2 is overexpressed in many human non-endocrine and endocrine tumors including colon, breast, prostate, brain, thyroid, and pituitary. COX-2 has an important role in angiogenesis and tumor growth. Thromboxane synthase (TS) catalyzes the synthesis of thromboxane A2 (TXA2), which is derived from arachidonic acid and prostaglandin H2 and is a vasoconstrictor and inducer of platelet aggregation. TXA2 stimulates tumor growth and spread of some tumors and TS appears to have a critical role in tumorigenesis in some organ systems. In this review, we examine the role of COX-2 and TS in various non-endocrine tumors, especially colon, breast, prostate, and brain as well as in endocrine tumors. The accumulating evidence points to an increasingly important role of COX-2 and TS in tumor progression and metastasis.
Onguru
Onder
O
Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
Casey
Mary B
MB
Kajita
Sabine
S
Nakamura
Nobuki
N
Lloyd
Ricardo V
RV
D000818:Animals; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004701:Endocrine Gland Neoplasms / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000201:enzymology*; D011453:Prostaglandins / Q000378:metabolism*; D013930:Thromboxane-A Synthase / Q000378:metabolism*
D011453:Prostaglandins; D051546:Cyclooxygenase 2; D013930:Thromboxane-A Synthase