Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal AXC/SSh rat ventral prostate and clonally derived AXC/SSh rat prostate cancer cells were evaluated for ability to metabolize estrone sulfate (E1S), estrone glucuronide (E1G), or dehydroepiandrosterone sulfate (DHEAS). Both normal and malignant prostate cells converted E1S to estrone. Neither normal nor malignant prostate cells had significant ability to metabolize DHEAS to DHEA, indicating differential specificity of prostate sulfatases(s) for estrogen and androgen sulfates. Both normal and neoplastic prostate cells possess beta-glucuronidase which hydrolyzed E1G to estrone. To assess potential physiologic consequences of these enzymatic activities, we determined the effect of steroid conjugates on in vitro proliferation of selected clonal lines of AXC/SSh rat prostate cancer cells. DHEAS, 10(-6) to 10(-9) M in decade intervals, did not affect in vitro proliferation of AXC/SSh prostate cancer cells; however, 10(-5) M DHEAS decreased in vitro proliferation of these cells. Neither E1S nor E1G, 10(-5) to 10(-9) M in decade intervals, affected in vitro proliferation of AXC/SSh prostate cancer cells. These findings suggest that low residual levels of steroid conjugates, which are not removed by charcoal stripping of serum, do not affect demonstrated in vitro androgen modulation of AXC/SSh rat prostate cancer cell proliferation (Cancer Res. 46, 3775-3781, 1986).
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PMID:Differential metabolism of dehydroepiandrosterone sulfate and estrogen conjugates by normal or malignant AXC/SSh rat prostate cells and effects of these steroid conjugates on cancer cell proliferation in vitro. 283 88

This is the history of discoveries of several enzyme tumor markers in the awardees laboratory. The first, beta-glucuronidase, was originally related to the physiological actions of estrogens and androgens. Perfection of histochemical techniques based on new substrates demonstrated the dual localization of beta-glucuronidase in endoplasmic reticulum and lysosomes. Tumor tissues, in general, are enriched with beta-glucuronidase. Next, acid phosphatase of the prostate gland possesses the distinctive property of undergoing inhibition by L-tartrate. This organ-specific inhibitor was incorporated into the Fishman-Lerner method for measuring serum acid phosphatase of prostatic origin. This significantly increased the specificity of the measurement of serum acid phosphatase for prostatic cancer. Finally, the discovery of the Regan Isoenzyme, placental alkaline phosphatase (PLAP) in a patient with disseminated lung cancer provided a tumor marker useful in the management of gonadal tumors, in particular. Closely related to PLAP is germ cell alkaline phosphatase which is eutopically expressed in seminoma. Finally, radioimmunolocalization and radioimmunotherapy of PLAP in these tumors have been achieved by others.
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PMID:The 1993 ISOBM Abbott Award Lecture. Isozymes, tumor markers and oncodevelopmental biology. 756 86

Hepatic dysfunction due to flutamide administration has been reported and this side effect often limits the use of the agent. The prediction of flutamide-induced hepatotoxicity is attributed to the proper use of the antiandrogen. In this study, we investigated whether hepatic dysfunction could be assessed by the metabolite profile in serum from patients receiving this drug. Serum samples were obtained from 15 patients with prostate cancer, 12 patients with no sign of hepatotoxicity and 3 patients with slight hepatic dysfunction during long-term flutamide treatment. We analyzed the metabolite profiles by LC/MS in selected ion monitoring mode and detected a new metabolite (M3) that was an oxidation product of flutamide. However, there were no consistent differences in the serum flutamide metabolites between patients with normal function and those suffering hepatic dysfunction. The metabolite profiles in the beta-glucuronidase-treated serum showed a similar pattern between normal functioning and dysfunctional groups. Thus, the profile of flutamide metabolites determined in serum may not contribute to the risk prediction of flutamide-related hepatotoxicity.
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PMID:Metabolite profiles of flutamide in serum from patients with flutamide-induced hepatic dysfunction. 1451 54

D-glucaric acid is a natural non-toxic compound produced in small amounts by mammals, including humans. In mammals, D-glucaric acid and D-glucaro-l,4-lactone are end-products of the D-glucuronic acid pathway. The enzyme D-glucuronolactone dehydrogenase has been found to be responsible for the oxidation of the lactone of D-glucuronic acid to D-glucaro-l,4;6,3-dilactone. This dilactone hydrolyzes spontaneously in aqueous solution to D-glucaro-l,4-lactone, a potent beta-glucuronidase inhibitor. D-glucaric acid is also found in many fruits and vegetables, with the highest concentrations found in grapefruits, apples, oranges, and cruciferous vegetables. b-glucuronidase is present in the circulation and probably all vertebrate tissues and is capable of hydrolyzing glucuronide conjugates. This enzyme is also produced by colonic microflora. Elevated b-glucuronidase activity is associated with an increased risk for various cancers, particularly hormone-dependent cancers such as breast and prostate cancer. D-glucaro-l,4-lactone increases detoxification of carcinogens and tumor promoters by inhibiting b-glucuronidase and preventing the hydrolysis of their glucuronides. D-glucaro-l,4-lactone was found to be formed from supplemented D-glucarate salt in the stomach and it is absorbed from the intestinal track, transported with the blood to different internal organs, and excreted in urine and, to a lesser extent, in bile. D-glucaro-l,4-lactone and its precursors exert their anticancer action in part through alterations in steroidogenesis accompanied by changes in the hormonal environment and proliferative status of the target organs. D-glucarates not only suppress cell proliferation and inflammation, but also induce apoptosis. By supplementing D-glucarates, one can favor the body's natural defense mechanism for eliminating carcinogens and tumor promoters and their effects.
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PMID:[The biological role of D-glucaric acid and its derivatives: potential use in medicine]. 1877 50

Since corticosteroid metabolism may be affected by disease states, the accurate and precise measurement of endogenous corticosteroids in urine is necessary to understand their biochemical roles. An efficient quantitative profiling of 21 endogenous corticosteroids in urine has been validated by liquid chromatography-tandem mass spectrometry (LC-MS/MS). After enzymatic hydrolysis with beta-glucuronidase, samples were purified using a solid-phase extraction cartridge and then separated through a sub-2 microm particle C18 column (2.1 mm x 50 mm, 1.9 microm) and quantified within 12.1 min using a triple quadrupole MS with electrospray ionization in positive ion mode. All corticosteroids resulted in the base-line separation, which is even achieved for stereo-isomers, such as alpha-/beta-cortol, alpha-/beta-cortolone, and allo-tetrahydrocortisol/tetrahydrocortisol. Overall recoveries ranged from 85% to 106% with limit of quantification ranged from 0.5 to 2.0 ng mL(-1) for the corticosteroids examined. The precision (% CV) and accuracy (% bias) of the assay were 1.7-7.8% and 95.1-105.4%, respectively, in 0.5-200 ng mL(-1) calibration ranges (r(2)>0.9903), for quality-control samples containing 21 endogenous corticosteroids at three different urinary concentrations. Clinical application included quantitative analysis from patients with both prostate cancer and benign prostatic hyperplasia with altered cortisol concentrations. The described LC-MS/MS method eliminates interference from other urine components, has excellent chromatographic resolution achieved by a small particle LC column with a sufficient sensitivity to allow the profiling of both gluco- and mineralo-corticosteroids at a time.
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PMID:Quantitative metabolic profiling of 21 endogenous corticosteroids in urine by liquid chromatography-triple quadrupole-mass spectrometry. 1910 Aug 88