The pro-apoptotic action of stilbene-induced COX-2 in cancer cells: convergence with the anti-apoptotic effect of thyroid hormone.
Constitutively expressed cyclooxygenase-2 (COX-2) is a marker of tumor cell aggressiveness. Inducible COX-2 has also been described in cancer cells and localizes in the cancer cell nucleus, where formation of a complex of mitogen-activated protein kinase (MAPK) and COX-2 is antecedent to p53-dependent apoptosis. The stilbene resveratrol is a model pharmacologic activator of this pro-apoptotic mechanism. Physiological concentrations of thyroid hormone are anti-apoptotic in several types of tumor cells. A mechanism by which the hormone is anti-apoptotic is disruption of the nuclear MAPK-COX-2 complex. We review here the apoptosis-relevant effects of resveratrol and thyroid hormone and then speculate about the significance of convergence of these actions in cancer cells in the intact organism. Clinical activity of resveratrol may be modulated by normal tissue levels of endogenous thyroid hormone, and hypothyroidism in the cancer patient -- whether spontaneous or induced by chemotherapeutic agents -- may permit full expression of the apoptotic activity of the administered stilbene. Chronic pharmacologic inhibition of COX-2 may oppose the pro-apoptotic effect of resveratrol.
Lin
Hung-Yun
HY
Ordway Research Institute Inc, Albany, NY 12208, USA. hlin@ordwayresearch.org
Davis
Paul J
PJ
Tang
Heng-Yuan
HY
Mousa
Shaker A
SA
Luidens
Mary K
MK
Hercbergs
Aleck H
AH
Davis
Faith B
FB
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D017209:Apoptosis; D049109:Cell Proliferation / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000187:drug effects / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D009369:Neoplasms / Q000201:enzymology*; D011494:Protein Kinases / Q000378:metabolism; D000077185:Resveratrol; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013267:Stilbenes / Q000494:pharmacology*; D013963:Thyroid Hormones / Q000378:metabolism* / Q000494:pharmacology
D016588:Anticarcinogenic Agents; D016207:Cytokines; D004791:Enzyme Inhibitors; D013267:Stilbenes; D013963:Thyroid Hormones; D051546:Cyclooxygenase 2; D011494:Protein Kinases; D000077185:Resveratrol