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

A liquid chromatographic-electrospray ionization-mass spectrometric (LC-ESI-MS) technique was developed to simultaneously determine the cyclooxygenase metabolites of arachidonic acid (6-keto-PGF(1alpha), PGD(2), PGE(2), PGF(2alpha), and PGJ(2)) produced by cultured cells. Samples were separated on a C(18) column with water-acetonitrile mobile phase, ionized by electrospray, and detected in the positive mode. Selected ion monitoring (SIM) of m/z 353, 335, 335, 319, and 317 were used for quantifying 6-keto-PGF(1alpha), PGD(2), PGE(2), PGF(2alpha), and PGJ(2), respectively. Prostaglandins were detected at concentrations as low as 1 pg (S/N=3) on the column. The method was used to determine the production of PGs from bovine coronary artery endothelial cells (ECs) and human prostate cancer cells (PC-3) with different degree of invasiveness. Bradykinin (10(-6) M) stimulated a marked increase in the production of 6-keto-PGF(1alpha), PGE(2), and PGF(2alpha) and a small increase of PGD(2) by ECs. 6-Keto-PGF(1alpha) was the major metabolite in these cells. The production of PGE(2) was threefold higher and PGD(2) was twofold higher in PC-3-S (invasive) cells than in PC-3-U (non-invasive) cells.
 ...
PMID:Liquid chromatographic-mass spectrometric determination of cyclooxygenase metabolites of arachidonic acid in cultured cells. 1253 46

The TRAMP model and human prostatic cancer (PCA) cell lines DU145 and PC3 are useful forchemopreventive studies. We compared the efficacy of 3 anti-oxidants [a water-soluble natural anti-oxidant. NAO (200 mg/kg). found in spinach leaves; epigallocatechin-3 gallate, EGCG (200 mg/kg), a major green tea polyphenol; and N-acetylcysteine, NAC (125 mg/kg)] plus vehicle in slowing spontaneous tumorigenic progression in TRAMP and wild-type male mice. Sacrifices occurred on weeks 5, 9, and 13. Prostatic histopathology and oxidative-stress blood markers were evaluated. Hyperplasias were ranked by a combination of severity grade and distribution (focal, multifocal, and diffuse). The effectivity of each tested compound in reducing the severity/focalness of hyperplasia varied from lobe to lobe. NAO exerted a significant effect on the dorsal and lateral lobes; NAC, on the anterior and ventral lobes, and EGCG, on the ventral lobe. When the most severe hyperplasia in all 4 lobes of TRAMPs was evaluated, only NAO reduced hyperplasia at weeks 9 and 13. Plasma peroxide levels in TRAMPs were reduced following oral administration of NAO or NAC for 13 weeks; EGCG only slightly reduced these levels. In NAO-treated DU 145 and PC3 PCA cells, inhibition of cellular proliferation occurred in a dose-dependent manner, increasing numbers of G1 cells and reducing ROS levels. The anti-oxidative and antiproliferative properties of NAO may explain its efficacy in slowing the spontaneous prostatic carcinogenic process in the TRAMP and its effects in the cell lines.
 ...
PMID:Slowing tumorigenic progression in TRAMP mice and prostatic carcinoma cell lines using natural anti-oxidant from spinach, NAO--a comparative study of three anti-oxidants. 1259 48

Understanding tumor vascular physiology is critically important for developing non-invasive, molecularly targeted diagnostic agents and therapies. In this study, using three different human prostate cancer xenografts (MDA PCa 2b, PC3, and LnCap), structural and physiological parameters of neoplastic vasculature and interstitum were explored with a widely available magnetic resonance imaging (MRI) pulse sequence (3D SPGR: spoiled gradient echo). Using dual injection technique employing two T1 contrast agents of different molecular masses (Weissleder, R., Cheng, H. C., Marecos, E., Kwong, K. K., Bogdanov, A., Jr. Eur. J. Cancer 34, 1448-1454 (1998).), steady state (SS) MRI measurements and dynamic contrast agent enhancement (DCE) MRI measurements were simultaneously acquired and analyzed using a two-compartment model for calculating parameters reflecting tumoral architecture and physiology. In particular, interstitial volume and vascular permeability were independently quantified using these two different MRI techniques. Relative vascular water exchange rate, calculated by the flip angle (FA) dependence of measured blood volume using SS technique, and vascular permeability of contrast agent, extrapolated from DCE MRI, were compared. It was found that the SS and DCE techniques were comparable and yielded similar qualitative results for extravascular compartment (interstitial volume). However, the permeability (water exchange rate and contrast agent vascular permeability) values were in disagreement. The results of MR studies are important for interpreting optical imaging results obtained using long-circulating of tumor-associated enzymatic activity.
 ...
PMID:Steady-state and dynamic contrast MR imaging of human prostate cancer xenograft tumors: a comparative study. 1262 76

Epidemiological studies have shown an inverse relationship between serum lycopene levels and the risk of prostate cancer. The objective of this study was to measure the effect of lycopene on the proliferation of LNCaP human prostate cancer cells in culture. A new, water-dispersible lycopene in an appropriate vehicle was used. The stock solution was diluted in the medium to obtain lycopene concentrations of 10(-6), 10(-5), and 10(-4) M; their corresponding vehicles were similarly diluted to be used as controls. Cells were grown for 48 hours in RPMI-1640 medium supplemented with 10% fetal bovine serum and antibiotics. Lycopene was then added at different concentrations, and the cells were allowed to grow for 24, 48, 72, and 96 hours. Lycopene at concentrations of 10(-6) and 10(-5) M significantly reduced the growth of LNCaP cells after 48, 72, and 96 hours of incubation, by 24.4% to 42.8% (P <.05). The inhibitory effect of lycopene was significantly higher than that of the corresponding vehicle controls. In a follow-up experiment, a lower range of lycopene concentrations (10(-9) to 10(-7) M) was used to determine whether there was a dose-response effect. Lycopene significantly decreased the growth of cells in a dose-dependent manner when cells were incubated for 24, 48, 72, or 96 hours (F = 3.150, 11.27, 54.51, and 297.5, respectively; P <.05). The growth inhibitory effect of lycopene on human prostate cancer cells observed in this study suggests a possibly important role for lycopene as an antioxidant in human prostate cancer; however, investigations of other mechanisms are warranted.
 ...
PMID:Effect of lycopene on prostate LNCaP cancer cells in culture. 1263 92

Permanent implantation of low energy (20-40 keV) photon emitting radioactive seeds to treat prostate cancer is an important treatment option for patients. In order to produce accurate implant brachytherapy treatment plans, the dosimetry of a single source must be well characterized. Monte Carlo based transport calculations can be used for source characterization, but must have up to date cross section libraries to produce accurate dosimetry results. This work benchmarks the MCNP code and its photon cross section library for low energy photon brachytherapy applications. In particular, we calculate the emitted photon spectrum, air kerma, depth dose in water, and radial dose function for both 125I and 103Pd based seeds and compare to other published results. Our results show that MCNP's cross section library differs from recent data primarily in the photoelectric cross section for low energies and low atomic number materials. In water, differences as large as 10% in the photoelectric cross section and 6% in the total cross section occur at 125I and 103Pd photon energies. This leads to differences in the dose rate constant of 3% and 5%, and differences as large as 18% and 20% in the radial dose function for the 125I and 103Pd based seeds, respectively. Using a partially updated photon library, calculations of the dose rate constant and radial dose function agree with other published results. Further, the use of the updated photon library allows us to verify air kerma and depth dose in water calculations performed using MCNP's perturbation feature to simulate updated cross sections. We conclude that in order to most effectively use MCNP for low energy photon brachytherapy applications, we must update its cross section library. Following this update, the MCNP code system will be a very effective tool for low energy photon brachytherapy dosimetry applications.
 ...
PMID:Brachytherapy dosimetry of 125I and 103Pd sources using an updated cross section library for the MCNP Monte Carlo transport code. 1272 22

In the United States, prostate cancer is the most commonly diagnosed male cancer and the second leading cause of all male cancer deaths. Furthermore, incidence rates are higher in African Americans than in any other racial group. Our laboratory is attempting to decipher the environmental and molecular mechanisms involved in the development of prostate cancer in African Americans. Because Africa is a mineral-rich continent, and the zinc levels in the water and diet are high, it is hypothesized that Africans may have genetically downregulated their zinc absorption capacity; otherwise, they would absorb abnormally high levels of zinc, resulting in various serious neurodegenerative and biochemical disorders. It is therefore possible that people of African origin may have a lower capacity to absorb zinc when compared with other racial groups because of their inherent downregulation of zinc transporters. Extensive research has shown that low serum levels of zinc are associated with the increased incidence of prostate cancer. We have evaluated 58 prostate cancer tissues in 2 major racial groups (30 from whites and 28 from African Americans) for their ability to express 2 major human zinc transporters, hZIP1 and hZIP2. In all 30 prostate cancer specimens obtained from white people, the degree of expression of these 2 zinc receptors was high when compared with age-matched and Gleason score-matched specimens obtained from African American patients. We also found a significant downregulation of these 2 zinc transporters in normal prostate tissues from African American men when compared with age-matched white men. The loss of the unique ability to retain normal intracellular levels of zinc may be an important factor in the development and progression of prostate cancer. Our observation that the uptake of zinc may be different in racial groups is intriguing and relevant. Once these data are confirmed in larger groups, this finding could have significant application as a preventive maneuver for at least for some people. Because dietary zinc supplements are relatively nontoxic, any efficacy trial would be low-risk.
 ...
PMID:Prostate cancer in African American men is associated with downregulation of zinc transporters. 1296 53

The Loma Linda University Proton Treatment Facility has treated over 5,000 patients for prostate cancer. Other institutions may find information regarding field size and range requirements for this population of patients useful for designing new proton beamlines. The maximum range, range modulation, and maximum field radius for 240 fields of prostate patients undergoing treatment were sampled and analyzed. Most fields required a range less than 290 mm of water, a modulation width less than or equal to 120 mm, and a radius less than 75 mm.
 ...
PMID:Range, range modulation, and field radius requirements for proton therapy of prostate cancer. 1452 9

Spinach leaves, containing several active components, including flavonoids, exhibit antioxidative, antiproliferative, and antiinflammatory properties in biological systems. Spinach extracts have been demonstrated to exert numerous beneficial effects, such as chemo- and central nervous system protection and anticancer and antiaging functions. In this review article, we present a compilation of data generated in our laboratories and those of other investigators describing the chemical composition of spinach, its beneficial effects, relative safety information, and its recommended inclusion in the human diet. A powerful, water-soluble, natural antioxidant mixture (NAO), which specifically inhibits the lipoxygenase enzyme, was isolated from spinach leaves. The antioxidative activity of NAO has been compared to that of other known antioxidants and found to be superior in vitro and in vivo to that of green tea, N-acetylcysteine (NAC), butylated hydroxytoluene (BHT), and vitamin E. NAO has been tested for safety and is well tolerated in several species, such as mouse, rat, and rabbit. NAO has been found to be nonmutagenic and has shown promising anticarcinogenic effects in a few experimental models, such as skin and prostate cancer; it has not shown any target-organ toxicity or side effects. The current review provides epidemiological and preclinical data supporting the efficacy of extracts of spinach and the safety of its consumption.
 ...
PMID:Composition, efficacy, and safety of spinach extracts. 1469 Jul 99

Prostate-specific antigen (PSA) is a serine protease and one of the most abundant proteins secreted by the human prostate epithelium. PSA is used as a well-established marker of prostate cancer. The involvement of PSA in several early events leading to the development of malignant prostate tumors has made it a target for prevention and intervention. It is thought that PSA cleaves insulin-like growth factor binding protein-3 (IGFBP-3), providing increased local levels of IGF-1, leading to tumor growth. Separately, there are data that suggest an enzymatic regulatory role for dietary boron, which is a serine protease inhibitor. In this study we have addressed the use of boric acid as a PSA inhibitor in an animal study. We have previously reported that low concentrations (6 ug/mL) of boric acid can partially inhibit the proteolytic activity of purified PSA towards a synthetic fluorogenic substrate. Also, by Western blot we have followed the degradation of fibronectin by enzymatically active PSA and have found significant inhibition in the presence of boric acid. We proposed that dietary supplementation with boric acid would inhibit PSA and reduce the development and proliferation of prostate carcinomas in an animal model. We tested this hypothesis using nude mice implanted subcutaneously with LNCaP cells in Matrigel. Two groups (10 animals/group) were dosed with boric acid solutions (1.7, 9.0 mgB/kg/day) by gavage. Control group received only water. Tumor sizes were measured weekly for 8 weeks. Serum PSA and IGF-1 levels were determined at terminal sacrifice. The size of tumors was decreased in mice exposed to the low and high dose of boric acid by 38% and 25%, respectively. Serum PSA levels decreased by 88.6% and 86.4%, respectively, as compared to the control group. There were morphological differences between the tumors in control and boron-dosed animals, including a significantly lower incidence of mitotic figures in the boron-supplemented groups. Circulating IGF-1 levels were not different among groups, though expression of IGF-1 in the tumors was markedly reduced by boron treatment, which we have shown by immunohistochemistry. These data indicate that low-level dietary boron supplementation reduced tumor size and content of a tumor trophic factor, IGF-1. This promising model is being evaluated in further studies.
 ...
PMID:Boron supplementation inhibits the growth and local expression of IGF-1 in human prostate adenocarcinoma (LNCaP) tumors in nude mice. 1471 51

Because prostate cancer has a long latency period and is typically diagnosed in elderly men, it represents an ideal candidate disease for chemoprevention. Therefore, even a modest delay achieved through intervention could have a significant impact on the outcome of this disease. Epidemiological and laboratory studies have provided convincing evidence that diet, genetic factors, and lifestyle are major causes of prostate cancer. Although surgery, radiotherapy, and hormone therapy are the most widely accepted curative options for a selected group of patients suffering from prostate cancer, the side effects of these treatments are many. In recent years, many dietary agents have been being described that show a wide range of chemopreventive effects in cell culture and selected animal model systems of prostate carcinogenesis. One such agent is the beverage tea, which, next to water, is the most popularly consumed beverage in the world. The epidemiological studies and recent data, amassed from various laboratories around the world, provide evidence that tea polyphenols such as epigallocatechin-3-gallate, epigallocatechin, and epicatechin-3-gallate may have the potential to lower the risk of prostate cancer in the human population. Recently, it has been shown that green tea polyphenols, when given to TRAMP, a transgenic mouse model that mimics progressive forms of human prostate cancer, exert remarkable preventive effects against prostate cancer development. Chemoprevention of prostate cancer by tea polyphenols appears to occur through the modulation of various molecular targets. This article attempts to address the issue of the possible use of tea, especially green tea, for the chemoprevention of prostate cancer.
 ...
PMID:Tea beverage in chemoprevention of prostate cancer: a mini-review. 1476 33


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>