"Lipopolysaccharide (LPS) causes apoptotic deletion of CD4+ CD8* thymocytes, a phenomenon that has been linked to immune dysfunction and poor survival during sepsis.  Given the abundance of thromboxane-prostanoid (TP) receptors in CD4+ CD8* thymocytes and in vitro evidence that thromboxane A₂ (TXA₂) causes apoptosis of these cells, we tested whether enhanced generation of TXA₂ plays a role in LPS-induced thymocyte apoptosis."

"These studies indicate that TXA(2) mediates a portion of apoptotic thymocyte death caused by LPS."

"In highly migratory subpopulations of human glioma cells differential mRNA display identified human thromboxane synthase as a strongly overexpressed motility associated gene.  Subsequently, we demonstrated that this enzyme is expressed in gliomas in vitro and in vivo and that specific thromboxane synthase inhibitors block migration, which is paralleled by a decrease of thromboxane B₂ formation.  These data implicate thromboxane synthase as an important regulator of glioma motility.  Interestingly, following thromboxane synthase inhibitor treatment the decrease of motillity rates is paralleled by increased caspase activity followed by intracellular DNA fragmentation and subsequent apoptotic cell death.  Prostanoid synthesis in general appears to be important in pathogenesis and progression of cancer because these metabolites influence cellular behaviour in several ways such as mitotic activity, cellular adhesion, invasion, angiogenesis and apoptosis."

"These data suggest that inhibitors of thromboxane synthase influence migration and apoptosis in both human glioma cells and human endothelial cells. An anti-invasive treatment strategy using this class of compounds may therefore not only sensitize glioma cells to conventional treatments inducing apoptosis but may also be supported by an anti-angiogenic effect.”

“We demonstrated that this enzyme is expressed in gliomas in vitro and in vivo and that specific thromboxane synthase inhibitors block migration, which is paralleled by a decrease of thromboxane B₂."

"Arachidonic acid metabolism through cyclooxygenase, lipoxygenase, or P-450 epoxygenase pathways can generate a variety of eicosanoids.  Thromboxane synthase (TxS) metabolizes the cyclooxygenase product, prostanglandin H2, into thromboxane A₂ (TXA2), which can cause vessel constriction, platelet activation, and aggregation.  Here we demonstrate that human prostate cancer (PCa) cells express enzymatically active TxS and that this enzyme is involved in cell motility.  In human PCa cell lines, PC-3, PC-3M, and ML-2 cells expressed higher levels of TxS than normal prostate epithelial cells or other established PCa cell lines such as DU145, LNCaP, or PPC-1.  We cloned and sequenced the full-length TxS cDNA from PC-3 cells and found two changes in the amino acid residues."

Immunohistochemical analysis of tumor specimens revealed that expression of TxS is weak or absent in normal differentiated luminal, or secretory cells, significantly elevated in less differentiated or advanced prostate tumors, and markedly increased in tumors with perineural invasion.  TxS expressed in PC-3 cells was enzymatically active and susceptible to carboxyheptal imidazole, an inhibitor of TxS.  The biosynthesis of TXA₂ in PC-3 cells was dependent on COX-2, and to a lesser extent, COX-1.  Treatment of PC-3 cells with a COX-1 selective inhibitor, piroxicam, reduced TXA2 production by 80%. Inhibition of TxS activity or blockade of TXA₂ function reduced PC-3 cell migration on fibronectin, while having minimal effects on cell cycle progression or survival.  Finally, increased expression of TxS in DU145 cells increased cell motility.  Our data suggest that human PCa cells express TxS and that this enzyme may contribute to PCa progression through modulating cell motility."

"The present study is the first report detailing the endogenous expression of TxS in human prostate cancer cells and its potential involvement in PCa cell motility and perineural invasion."

“Compared with non-diabetics, patients with Type II diabetes mellitus (T2Dm) have a two-to four-fold increased risk of ischemic cardiovascular disease, a risk largely independent of concomitant hypertension, hypercholesterolemia, and smoking.”

“In addition to TXA₂, which is capable of causing bronchoconstriction, lasma extravasation, and chemokine expression, its stable metabolite 11-dehydro-TXB₂ might also be directly involved in the recruitment of ecosinophils, basophils and presumably TH2 lymphocytes to sites of inflammation.”

"The results of this study suggest that nicotinic acid increases thromboxane and leukotriene synthesis which may not be beneficial for patients with cardiovascular diseases or asthma.  In contrast, the increase of prostacyclin production and the inhibition in thromboxane and leukotriene synthesis by pyriodoxine might be beneficial in disorders where the production of prostacyclin is decreased and the formation of thromboxane and cysteinyl leukotrienes is enhanced.

"The treatment with nicotinic acid increased 11-DHTXB₂ excretion to 2.6 fold and leukotriene E4 excretion to twice the basal values."

“Women with android obesity had higher levels of 8-iso PGF2alpha and 11-dehydro-TxB₂ than nonobese women.” 

“Both 8-iso PGF2alpha and 11-dehydroTxB₂ were higher in women with android obesity than women with gynoid obesity” 

“Of 20 women with android obesity, 11 achieved successful weight loss, which was associated with statistically significant reductions in C-reactive protein (median change 23%  p<.05), 8-iso PGF2alpha (median change 32%  p=.04) and 11-dehydro-TXB2 (median change 54% p=.005)." 

"In aspirin-treated patients, urinary concentrations of 11-dehydro thromboxane B₂ predict the future risk of myocardial infarction or cardiovascular death. These findings raise the possibility that elevated urinary 11-dehydro thromboxane B₂ levels identify patients who are relatively resistant to aspirin and who may benefit from additional antiplatelet therapies or treatments that more effectively block in vivo thromboxane production or activity."

"The aim of this study was to determine the extent of change in platelet and coagulation markers in the acute phase of ischemic stroke and to assess the utility of marker mesurement in stroke subtype classification.  Urinary 11-dehydro-thromboxane B₂ (11-deTXB₂), a marker of in vivo platelet activation, and markers of coagulation activation, including prothrombin fragment 1 +2 (F1 + 2), thrombin-antithrombin complex (TAT) and fibrinogen, were measured in 25 patients with ischemic stoke within 24 h of onset symptoms. Eight patients taking aspirin at the time of the stroke had signficantly lower 11-dTXB2 values than patients not taking aspirin (964 vs. 4,314 pg/mg of creatinine P=0.0007).  Stroke patients not taking aspirin had significantly higher 11-dTXB2 concentration than age-matched controls (4,314 vs. 1,788 pg/mg of creatinine; P= 0.0006)."

"An unstable intermediate between the prostaglandin endoperoxides and thromboxane B_2.  The compound has a bicyclic oxaneoxetane structure.  It is a potent inducer of platelet aggregation and causes vasoconstriction.  It is the principal component of rabbit aorta contracting substance ORCS)."

"These results suggest that bronchial asthma patients with high urinary 11-DHTXB₂ levels could markedly respond to Seratrodast treatment. ”