Biology of Cox-2: An Application in Cancer Therapeutics

INSERM U-955, Team No. 10, Institut Mondor de Recherche Biomédicale, Université Paris Est, 94010 Créteil, Paris, France.
Current drug targets (Impact Factor: 3.02). 03/2011; 12(7):1082-93. DOI: 10.2174/138945011795677764
Source: PubMed


Cyclooxygenase-2 (Cox-2) is an inducible enzyme involved in the conversion of arachidonic acid to prostaglandin and other eicosanoids. Molecular pathology studies have revealed that Cox-2 is over-expressed in cancer and stroma cells during tumor progression, and anti-cancer chemo-radiotherapies induce expression of Cox-2 in cancer cells. Elevated tumor Cox-2 is associated with increased angiogenesis, tumor invasion and promotion of tumor cell resistance to apoptosis. Several experimental and clinical studies have established potent anti-cancer activity of NSAID (Non-steroidal anti-inflammatory drugs) and other Cox-2 inhibitors such as celecoxib. Much attention is being focused on Cox-2 inhibitors as beneficial target for cancer chemotherapy. The mode of action of Cox-2 and its inhibitors remains unclear. Further clinical application needs to be investigated for comprehending Cox-2 biological functions and establishing it as an effective target in cancer therapy.

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Available from: Prakash S Bisen
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    • "NSAIDs are known as potent anti-inflammatory agents that act through the inhibition of the COX enzyme and the subsequent inhibition of prostaglandins which are catalysed by COX enzymes at the site of inflammation [45]. This type of drug is usually accompanied by side effects; however, some studies have suggested that selective COX-2 inhibitors such as celecoxib may produce superior anti-inflammatory drugs with substantial safety advantages over existing NSAIDs [46]. "
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    • "However, the study presented here unexpectedly showed that hTERT knocking down led to a significant increase in COX2 expression, a well-defined oncogenic promoter, in gastric, cervical and breast cancer cells. Cyclooxygenase 2 is a rate-limiting enzyme in the production of diverse prostanoids with potent biological activities and induces oncogenesis by promoting cell proliferation and resistance to apoptosis (Wang and Dubois, 2004; Sobolewski et al, 2010; Wu et al, 2010; Chen et al, 2011; Khan et al, 2011). Given these facts, it is thus of importance to define the functional significance of COX2 upregulation in hTERTdepleted cancer cells. "
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    Full-text · Article · May 2013 · British Journal of Cancer
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    • "and angiogenesis (Chen et al., 2009; Liu et al., 2011), inhibiting apoptosis and immune surveillance (Ohno et al., 2005), and enhancing drug resistance (Mehar et al., 2008). These findings suggest that COX-2 may play a key role in carcinogenesis and makes it a potential target in cancer therapy (Ghosh et al., 2010; Khan et al., 2011). "
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