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)

Components of malignant invasion, namely cellular adhesion, motility, and proteolytic capability provide potential sites of pharmacological intervention for malignancy. In this study, a series of experiments were performed to examine the effects of N-(4-hydroxyphenyl) retinamide (4-HPR, Fenretinide) on cellular adhesion, motility and proteolytic activity of established prostate cancer cell lines, TSU-PR 1 and PC-3. Radioadhesion study showed that the treatment of TSU-PR 1 and PC-3 cells with 10(-6) M of 4-HPR resulted in a 32% and 37% reduction (p < 0.05), respectively, in the cellular adhesion to the matrigel extract. Radiomigration assay also demonstrated that 4-HPR concentration of 10(-6) M reduced the cellular motility by 29% in TSU-PR1 and 28% in PC-3 cells (p < 0.05). Spectrolyse PL indirect chromogenic assay revealed an increase in total activatable uPA activity (TSU-PR 1: 25%, PC-3: 32%, P < 0.05), while Spectrolyse UK direct assay demonstrated a mild, but a statistically significant reduction (PC-3: 5%, TSU-PR1: 9%, P < 0.05) in active uPA activity. Northern analysis and ELISA assays showed that 4-HPR at 10(-6) M enhances the expression of type 1 plasminogen activator inhibitor (PAI-1). Type IV collagenase western blot analysis and densitometry did not demonstrate suppression of the enzyme secretion, but in fact suggested increased translation of the enzyme when treated with 10(-6) M concentration of fenretinide. The results of this study demonstrate that 4-HPR inhibits in vitro cellular adhesion and motility of human prostate adenocarcinoma cell lines, TSU-PR1 and PC-3. Additionally, uPA and PAI-1 assay results suggest that 4-HPR may impair active uPA's proteolytic activity while upregulating the expression of total activatable uPA and PAI-1. The results of this study therefore support 4-HPR's role as a potential anti-invasive agent.
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PMID:In vitro anti-invasive effects of N-(4-hydroxyphenyl)-retinamide on human prostatic adenocarcinoma. 765 32

Breast cancer and prostate cancer, the most common cancers in American women and men, respectively, are major public health concerns. Investigations into the prevention and early detection of breast and prostate cancer include research on the potential impact of diet, particularly dietary fat, on breast cancer risk; the chemoprevention of breast cancer using tamoxifen and N-(4-hydroxyphenyl)retinamide(4-HPR); the importance of mammography in early detection of breast cancer; the potential of finasteride in preventing or retarding the progression of early-stage prostate cancer; and improved detection of prostate cancer by combining various screening modalities. The importance of transferring information gained though such research to the health care community cannot be overemphasized. Further, it is critical that cancer prevention and detection education be built into the curricula of leading medical and biomedical institutions. Education is key to developing a strong and vigorous cancer prevention and early detection research program.
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PMID:Expanding horizons in breast and prostate cancer prevention and early detection. The 1992 Samuel C. Harvey Lecture. 836 43

N-(4-Hydroxyphenyl)retinamide (4-HPR, Fenretinide) is a retinoid derivative with antineoplastic activity in various tumor types including prostate carcinoma. The mechanism of action of 4-HPR toxicity is unknown. 4-HPR induces apoptosis in leukemia- and lymphoma-derived cells, neuroblastoma, and small cell lung cancers. The present study was designed to investigate: (a) the mechanism of 4-HPR cytotoxicity in prostate cancer cells; and (b) correlate increased expression of transforming growth factor beta 1 (TGF beta 1) with induction of apoptosis. 4-HPR exposure to PC-3 cells in vitro was associated with apoptosis as evidenced by increased incidence of hypodiploid nuclei in propidium iodide fluorescence histograms and DNA fragmentation. An increase in the percentage of nuclei in the G1 phase of the cell cycle preceded induction of apoptosis. TGF beta 1-increased expression was noted in mRNA levels and in secretion of active TGF beta 1 into culture media. TGF beta 1 and TGF-beta receptor type II detected immunohistochemically were increased in 4-HPR-treated PC-3 cells. Furthermore, 4-HPR-induced cytotoxicity in PC-3 cells was abrogated by the addition of anti-TGF beta 1 antibody. In BT-20 cells, a 4-HPR-resistant breast carcinoma cell line, apoptosis was not observed after exposure to 4-HPR nor was TGF beta 1 expression enhanced in stained cells or in conditioned media. It is concluded that 4-HPR induces the expression of TGF beta 1 in association with the induction of apoptosis.
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PMID:Fenretinide: induction of apoptosis and endogenous transforming growth factor beta in PC-3 prostate cancer cells. 899 39

Many anticipate that application of findings in molecular genetics will help to achieve greater precision in defining high-risk populations that may benefit from chemopreventive interventions. We must recognize, however, that genetic susceptibility, environmental factors, and complex gene-environment interactions are all likely to be risk determinants for most cancers. Cohort studies of twins and cancer indicate that having "identical" genes is generally not a very accurate predictor of cancer incidence. Data from twin studies support the suggestion that environmental factors such as tobacco use significantly influence cancer risk. The complexities of the genetic contribution to disease risk are exemplified by the development of Duchenne muscular dystrophy in only one of monozygotic twin girls, hypothesized to be the result of X chromosome inactivation, with the distribution patterns of the X chromosome being skewed to the female X in the manifesting twin and to the male X in the normal twin. Evidence from transgenic and genetic-environmental studies in animals support the possibility of genetic-environmental interactions. Calorie restriction modifies tumor expression in p53 knockout mice; a high-fat, low-calcium, low-vitamin D diet increases prepolyp hyperplasia formation in Apc-mutated mice; and calorie restriction early in life influences development of obesity in the genetically obese Zucker rat (fafa). Such environmental modulation of gene expression suggests that chemoprevention has the potential to reduce risk for both environmentally and genetically determined cancers. In view of the growing research efforts in chemoprevention, the NCI has developed a Prevention Trials Decision Network (PTDN) to formalize the evaluation and approval process for large-scale chemoprevention trials. The PTDN addresses large trial prioritization and the associated issues of minority recruitment and retention; identification and validation of biomarkers as intermediate endpoints for cancer; and chemopreventive agent selection and development. A comprehensive database is being established to support the PTDN's decision-making process and will help to determine which agents investigated in preclinical and early phase clinical trials should move to large-scale testing. Cohorts for large-scale chemoprevention trials include individuals who are determined to be at high risk as a result of genetic predisposition, carcinogenic exposure, or the presence of biomarkers indicative of increased risk. Current large-scale trials in well-defined, high-risk populations include the Breast Cancer Prevention Trial (tamoxifen), the Prostate Cancer Prevention Trial (finasteride), and the N-(4-hydroxyphenyl) retinamide (4-HPR) breast cancer prevention study being conducted in Milan. Biomarker studies will provide valuable information for refining the design and facilitating the implementation of future large-scale trials. For example, potential biomarkers are being assessed at biopsy in women with ductal carcinoma in situ (DCIS). The women are then randomized to either placebo, tamoxifen, 4-HPR, or tamoxifen plus 4-HPR for 2-4 weeks, at which time surgery is performed and the biomarkers reassessed to determine biomarker modulation by the interventions. For prostate cancer, modulation of prostatic intraepithelial neoplasia (PIN) by 4-HPR and difluoromethylornithine is being investigated; similar studies are being planned for oltipraz, dehydroepiandrosterone, and vitamin E plus selenomethionine. The validation of biomarkers as surrogate endpoints for cancer incidence in high-risk cohorts will allow more agents to be evaluated in shorter studies that use fewer subjects to achieve the desired statistical power.
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PMID:Cancer risk factors for selecting cohorts for large-scale chemoprevention trials. 902 95

Hormonally insensitive prostate cancer is a relatively slow-growing, but usually fatal, disease with no long-term treatment options. Transformation of normal prostate cells to a malignant phenotype often involves corruption of the apoptotic machineries. Bcl-2 protein is one of the key inhibitors of apoptosis and is often unregulated in advanced prostate cancer. The prostate cancer cell line DU-145 was used as a model of a hormonally insensitive, advanced prostate cancer. Cell growth in liquid culture was significantly inhibited by antisense Bcl-2 oligonucleotides compared with control sense oligonucleotides; inhibition by these oligonucleotides was significantly enhanced on combination with the synthetic retinoid N-(2-hydroxyphenyl)all-trans-retinamide (2-HPR). Interestingly, growth inhibition occurred in the absence of apoptosis as measured using two assay techniques. We hypothesize that in these recalcitrant cells the apoptotic pathway is compromised at several levels, and Bcl-2 may play another role in promoting cell growth. The use of Bcl-2 antisense oligonucleotides plus 2-HPR may provide a novel approach to therapy of hormone-resistant prostate cancer.
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PMID:Growth inhibition of DU-145 prostate cancer cells by a Bcl-2 antisense oligonucleotide is enhanced by N-(2-hydroxyphenyl)all-trans retinamide. 951 52

The influence of chemical carcinogen, hormonal stimulation, and chronic dietary administration of the synthetic retinoid, N-(4-hydroxyphenyl)-all-trans-retinamide (4-HPR), on the induction of prostate cancer in male Wistar-Unilever rats was determined. Three different tumor induction regimens were used: (a) a single i.v. dose of 50 mg of N-methyl-N-nitrosourea (MNU) per kg body weight, followed by chronic androgen stimulation via s.c. implantation of two silastic capsules containing 40 mg testosterone each; (b) a single i.v. dose of 50 mg of MNU per kg body weight (no testosterone treatment); and (c) chronic androgen stimulation with implanted testosterone capsules (no MNU treatment). In a fourth series of animals, the incidence of spontaneous prostate tumors was determined in groups of rats receiving neither carcinogen nor hormone stimulation. Within each series, parallel groups of animals were fed a control (vehicle-supplemented) diet or control diet supplemented with 4-HPR beginning 1 day after carcinogen administration; retinoid administration was continuous until termination of the study at 450 days. The incidence of accessory sex gland cancer in rats treated sequentially with MNU + testosterone was >60%, in comparison with cancer incidences of <20% in rats receiving MNU only and <5% in rats treated with testosterone only. No spontaneous accessory sex gland tumors were observed in rats receiving no carcinogen and no testosterone. Tumor induction in the accessory sex glands by MNU + testosterone was relatively specific for the prostate: the incidence of carcinoma of the dorsolateral/anterior prostate was more than 5-fold greater than the incidence of cancer present only in the seminal vesicle. 4-HPR conferred no protection against cancer induction in the prostate by any regimen of MNU and/or testosterone. These results demonstrate the importance of both carcinogen exposure and hormone stimulation on the induction of neoplasia in the prostate of Wistar-Unilever rats.
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PMID:Influence of N-methyl-N-nitrosourea, testosterone, and N-(4-hydroxyphenyl)-all-trans-retinamide on prostate cancer induction in Wistar-Unilever rats. 969 56

To explore the mechanisms underlying the chemopreventive effects of the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4-HPR) in prostate cancer, we evaluated the anti-proliferative and apoptosis-inducing effects of 4-HPR in the androgen-sensitive human prostate cancer cell line LNCaP. 4-HPR decreased the number of viable LNCaP cells (as measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay) in a dose-dependent manner. Although 4-HPR exerted a modest G1 cell-cycle block (as determined by flow cytometry), its effect on reduced cell number appeared to result primarily from induction of apoptosis (as measured by an enzyme-linked immunosorbent assay and flow-cytometric assays). The mitogenic effects of R1881, a non-metabolizable androgen that potently induces LNCaP cell proliferation, was completely blocked by greater than 0.5 microM 4-HPR. Furthermore, increasing the R1881 concentration in the presence of 2.0 microM 4-HPR increased apoptotic cell death. 4-HPR decreased prostate-specific antigen (PSA) protein levels in conditioned medium and decreased PSA mRNA expression. 4-HPR also decreased the ratio of bcl-2 to bax mRNA expression in LNCaP cells by approximately 45%, indicating that the apoptotic effects of 4-HPR may be mediated, at least in part, by alterations in the bcl-2/bax-regulated apoptotic pathway. N-acetylcysteine (4 mM) completely blocked the anti-proliferative and apoptotic-inducing effects of 4-HPR, suggesting that an oxidative mechanism may be involved. We concluded that (i) 4-HPR exerts growth-suppressive and apoptotic effects on LNCaP cells, (ii) 4-HPR can interact with androgen to suppress proliferation and induce apoptosis, (iii) the apoptotic effects of 4-HPR may be mediated in part by the bcl-2/bax pathway, and (iv) a pro-oxidant mechanism may contribute to the anti-proliferative and apoptotic-inducing effects of 4-HPR.
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PMID:Mechanistic studies of the effects of the retinoid N-(4-hydroxyphenyl)retinamide on prostate cancer cell growth and apoptosis. 1020

An NCI-sponsored, phase II trial of N-(4-hydroxyphenyl)- retinamide (4-HPR) in patients with organ-confined prostate cancer in the period prior to radical prostatectomy was carried out. Thirty-seven men with the histologic diagnosis of prostate cancer planning to have radical prostatectomy entered the study after informed consent and were given 4-HPR (or matching placebo) as a single daily dose (two 100-mg capsules of 4-HPR or two capsules of placebo daily) for 3 weeks prior to surgery. Four men dropped out for unrelated reasons. Thirty-three men completed the study. At the time of surgery, repeat biopsies of the prostate were performed to study the effects of the drug on potential surrogate endpoint biomarkers (SEBs) of malignancy within the tissue. The panel of potential SEBs of malignancy include p53, cytomorphometric indices, ploidy, PNCA, erbB-2, erbB-3, EGF receptor, TGF-alpha tumor-associated glycoprotein-72, fatty acid synthetase and Lewis Y antigen. Twenty-three patients had matching pre- and posttherapy lesions and were considered informative. Results from the patients indicate significant differential expression of biomarkers in pretreatment specimens of uninvolved prostatic tissue (normal-appearing epithelia) prostatic intraepithelial neoplasia (PIN) and prostate cancer. The mean erbB-2 expression was 0.58 in uninvolved vs. 1.04 in PIN (p = 0.002); while the mean erbB-2 expression was 1.35 in prostate cancer (p = 0.0007, uninvolved vs. prostate cancer). A similar pattern of increased biomarker expression between uninvolved and PIN or prostate cancer tissues can be observed for EGF receptor (mean = 1.21, 1.87 and 1.76 for uninvolved, PIN and prostate cancer, respectively) and erbB-3 (mean = 0.81, 1.59 and 1.30 for uninvolved, PIN and prostate cancer, respectively). There were no statistically significant differences in biomarkers observed in the 4-HPR-treated patients when compared with placebo-treated control patients. There was a posttreatment up-regulation of biomarkers observed in both groups of patients. This observation is most likely explained by an effect due to the diagnostic sextant biopsy equally affecting both groups of patients. Results from this study do not demonstrate a chemoprevention effect of 4-HPR on tissue-based SEBs at the dose given.
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PMID:Evaluation of biomarker modulation by fenretinide in prostate cancer patients. 1032 1

A long latent period of 20 to 30 years may be involved in the multistep process of carcinogenesis represented by prostatic intraepithelial neoplasia (PIN) in the prostate. It is, therefore, possible that progression to a malignant state could be blocked or reversed during this time. Retinoids not only have the ability to block steps in the process of carcinogenesis but they may also modulate or reverse some malignant characteristics of cancer cells. This study focuses on the ability of N-(4-hydroxyphenyl)-retinamide (4-HPR), a synthetic retinoid, to reverse malignant characteristics towards a normal phenotype, using the human prostate carcinoma cell line DU-145. These malignant characteristics include abnormal cell proliferation, intermediate filament expression, motility, invasion, and cell survival. Results show that 1 microM and 10 microM 4-HPR caused 31% and 96% inhibition of growth, while all-trains retinoic acid (ATRA) produced similar effects at 10 and 100 microM, making 4-HPR ten times more effective than ATRA. While DU-145 cells show strong immunostaining for vimentin, treatment with 1 microM 4-HPR for eight days caused a marked decrease in vimentin staining. This was accompanied by a change from an elongated to an epithelial cell morphology. Densitometric analysis of Western blots for vimentin showed a 53% decrease in vimentin expression in 1 microM 4-HPR treated cells. Concomitant with the decrease in vimentin expression, cell motility and invasive ability also decreased by 32% and 52%, respectively. Growth inhibition was accompanied by DNA fragmentation and apoptosis. Exposure of cells to 1 microM 4-HPR caused a marked upregulation of nuclear retinoid receptors RARalpha and a detectable expression of RARgamma. These results suggest that inhibition of growth and vimentin expression, and induction of apoptosis by 4-HPR in prostate cancer cells may occur via a receptor-mediated mechanism involving transrepression of AP-1 by retinoid receptors. We propose that vimentin may serve as a useful intermediate marker for early detection of prostate cancer in biopsy specimens and that 4-HPR may be effective in blocking several steps in prostate carcinogenesis as well as the progression of PIN to invasive carcinoma.
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PMID:Modulation of the malignant phenotype of human prostate cancer cells by N-(4-hydroxyphenyl)retinamide (4-HPR). 1043 11

Previous investigations have demonstrated that a synthetic retinoid, N-(4-hydroxyphenyl) retinamide (4-HPR), inhibits the invasion of prostate adenocarcinoma in vitro. Urokinase-type plasminogen activator (uPA) is a prerequisite for tumor invasion. The purpose of this study was to evaluate the effects of 4-HPR on uPA and plasminogen activator inhibitor-1 (PAI-1) in prostate cancer. Human prostate adenocarcinoma cell lines, TSU-PR1 and PC3, were grown in serum-free media containing 4-HPR. Cellular mRNA and protein were subsequently extracted. Northern blot analysis, enzyme-linked immunosorbent assay (ELISA) and chromogenic functional analysis were performed on the samples. Administration of 10(-6) M 4-HPR for 3 days resulted in an increase in uPA mRNA expression (TSU-PR1: 391%, PC3: 356%), and a simultaneous increase in PAI-1 mRNA expression (TSU-PR1: 217%, PC3: 235%) was observed. ELISA concomitantly demonstrated a significant increase (p < 0.05) in uPA protein in the conditioned media (TSU-PR1: 134%, PC3: 139%) and cell lysates (TSU-PR1: 284%, PC3: 255%). Both cell lines demonstrated a significant increase (p < 0.05) in PAI-1 protein in the conditioned media (TSU-PR1: 152%, PC3: 167%) and cell lysates (TSU-PR1: 170%, PC3: 222%). Concentrations below 10(-6) M failed to alter the protein production of either uPA or PAI-1. The functional uPA assay demonstrated a reduction of the proteolytic activity of uPA (TSU-PR1: 13%, PC3: 7%) in cell lysates of 10(-6) M 4-HPR (p < 0.05), while there was minimal uPA activity in the conditioned media. 4-HPR stimulates a paradoxical increase in uPA and PAI-1, but the anti-invasive effects of 4-HPR are consistent with the increase in both uPA and PAI-1, resulting in an overall reduction of functional uPA activities.
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PMID:Effects of N-(4-hydroxyphenyl) retinamide on urokinase-type plasminogen activator and plasminogen activator inhibitor-1 in prostate adenocarcinoma cell lines. 1082 59


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