thromboxane-b2 and Prostatic-Neoplasms

Thromboxane A2 (TXA2) is a platelet- and cyclooxygenase-derived eicosanoid that has been linked to metastasis. We investigated the role of TXA2 in the development of lethal prostate cancer in African American (AA) and European American (EA) men.. We measured urinary 11-dehydrothromboxane B2 (TXB2), a stable metabolite of TXA2, with mass spectrometry. Samples were obtained from 977 cases and 1022 controls at time of recruitment. We applied multivariable logistic and Cox regression modeling to examine associations of TXB2 with prostate cancer and patient survival. The median survival follow-up was 8.4 years, with 246 deaths among cases. Aspirin use was assessed with a questionnaire. Race was self-reported.. Urinary TXB2 was inversely associated with aspirin use. High (>median) TXB2 was associated with prostate cancer in AA (adjusted odds ratio [OR] = 1.50, 95% confidence interval [CI] = 1.13 to 2.00) but not EA men (OR = 1.07, 95% CI = 0.82 to 1.40), suggesting upregulated TXA2 synthesis in AA men with prostate cancer. High TXB2 was positively associated with metastatic prostate cancer (OR = 2.60, 95% CI = 1.08 to 6.28) compared with low (≤median) TXB2. Furthermore, high TXB2 was also associated with all-cause (adjusted hazard ratio = 1.59, 95% CI = 1.06 to 2.40) and prostate cancer-specific mortality (hazard ratio = 4.74, 95% CI = 1.62 to 13.88) in AA men only.. We report a distinct association of TXB2 with prostate cancer outcomes in AA men. In this high-risk group of men, upregulation of TXA2 synthesis may promote metastasis and lethal disease. Our observation identifies a potential benefit of aspirin in preventing lethal prostate cancer through inhibition of TXA2 synthesis.

Topics: Aspirin; Black or African American; Humans; Male; Prostatic Neoplasms; Thromboxane A2; Thromboxane B2

In patients with chronic urinary obstruction the excretion of prostaglandin E(2) (PGE2) and thromboxane B(2) (TXB2) was measured. During obstruction signs of an increased vasoconstrictor (TXB2)- and a decreased vasodilator (PGE2) activity were found. After percutaneous nephropyelostomy a reverse pattern with decrease of the initially high (TXB2) excretion and increase of the PGE(2)excretion was observed. It is suggested that these changes of the arachidonic acid metabolism previously found in animals also take part in the pathophysiological changes in humans after relief of urinary obstruction having significant effect of renal blood flow, glomerular filtration rate and tubular function in obstructive nephropathy in humans.

Topics: Adult; Dinoprostone; Female; Humans; Hydronephrosis; Kidney Calculi; Male; Middle Aged; Nephrostomy, Percutaneous; Prostatic Neoplasms; Thromboxane B2; Tissue Adhesions; Ureteral Obstruction