Cancer prostate-specific antigen

No association. - = Inverse association. + = Positive association. ATBC = a-Tocopherol, p-Carotene Cancer Prevention Study. PSA = Prostate-specific antigen. 

Intervention trials confirmed this protective role of lycopene on prostate cancer risk. Three primary intervention studies evaluated the effect of lycopene supplementation on prostate cancer risk or on certain risk markers such as prostate-specific antigen (PSA) plasma concentration or oxidative alterations of leucocyte DNA. - All showed increases of plasma and prostate lycopene levels after diet supplementation with lycopene and inverse correlations between tumor incidence and risk biomarkers. 

Prostate-specific antigen (PSA) is a useful marker for detecting prostate cancer at early stages, predicting outcome for localized disease, defining disease-free status, and monitoring response to... 

Prostate-specific antigen (PSA) a substance secreted by the prostate and normally carried by ducts to the urethra during ejaculation PSA is used as a screening test for prostate cancer. 

Carter, H. B., Epstein, J. I., Chen, D. W., et al. Recommended prostate-specific antigen testing intervals for the detection of curable prostate cancer. JAMA 227,1456-1460 (1997). 

Stamey, T. A. Lower limits of detection, biological detection limits, functional sensitivity, or residual cancer detection limit/sensitivity reports on prostate-specific antigen assays mislead clinicians. Clin. Chem. 42, 849-850 (1996). 

Population studies associate tomato consumption with reduced risk to prostate cancer. The most positive associations have come from cohort studies performed before the prostate-specific antigen (PSA)-screening era, and these studies have suggested that the tomato/lycopene effect was the strongest for clinically relevant prostate cancers (Giovannucci 2007). Small human studies have shown in vivo antioxidant effects for tomato products but evidence for lycopene alone is weak (Chen et al. 2001, Porrini and Riso 2000, Riso et al. 2004, Zhao et al. 2006). Animal and tissue culture studies have been... 

Note PCa, prostate cancer WM, white male DES, diethylstilbestrol AR, androgen receptor PSA, prostate specific antigen and PAP, prostatic acid phosphatase. 

Barber, NJ, X Zhang, G Zhu et al. 2006. Lycopene inhibits DNA synthesis in primary prostate epithelial cells in vitro and its administration is associated with a reduced prostate-specific antigen velocity in a phase II clinical study. Prostate Cancer Prostatic Dis 9 407 -13. 

Giovannucci, E. 2007. Does prostate-specific antigen screening influence the results of studies of tomatoes, lycopene, and prostate cancer risk 7 Natl Cancer Inst 99(14) 1060-1062. 

Miyata, Y, H Sakai, T Hayashi, and H Kanetake. 2003. Serum insulin-like growth factor binding protein-3/ prostate-specific antigen ratio is a useful predictive marker in patients with advanced prostate cancer. Prostate 54 125-132. 

On patients with cancer, the effects of green tea catechins, soy isoflavones and quercetin as chemoprotective/chemotherapeutic agents have also been studied. Although results have not been entirely satisfactory, a partial response has been achieved in some trials. For example, small decreases in plasma concentration of prostate-specific antigen were observed in prostate cancer patients who consumed soy isoflavones. Nevertheless, results in individuals with premalignant disease who consumed green tea polyphenols support their advancement into phase III clinical intervention trials aimed at the prevention of PIN, leukoplakia, or premalignant cervical disease (Thomasset and others 2006). 

Hernandez, J. Thompson, I. M., Prostate specific antigen A review of the validation of the most commonly used cancer biomarker, Cancer 2004, 101, 894 904... 

Provenge is a cancer vaccine using cell therapy technique. Dendritic cells are removed from patients. These cells are treated with the prostate-specific antigen prostatic acid phosphatase (PAP), which is present in 95% of prostate cancer cases. The activated dendritic cells are returned to the patients and they stimulate the T cells to destroy cancer cells expressing the PAP, thus treating the tumor. 

Acid phosphatase retains its activity for a long period and hence is useful in forensic science to detect semen but has now been superseded by DNA fingerprinting. The activity in blood was used in the diagnosis of prostatic cancer but was superseded by PSA (prostate specific antigen). 

Flutamide was the first drug used in prostate cancer therapy for which the withdrawal syndrome was reported. In that study, 40% of patients showed a decline in prostate specific antigen (PSA) levels after cessation of flutamide from the therapeutic protocol. The decline in PSA levels was associated with an improvement of the clinical symptoms. Based on these paradoxical observations, the concept of sequenced androgen ablation was proposed [217]. Several phase II clinical studies were performed, demonstrating safety and tolerability, however, a direct comparison in randomised phase III trials is necessary [218]. 

Whether long-term treatment can reduce prostate cancer risk is unknown decreases prostate-specific antigen (PSA)... 

Monitor response to therapy for prostate cancer by measuring prostate-specific antigen (PSA) levels... 

Due to the long natural history of recurrent prostate cancer, longer follow-up is required to assess the ultimate impact of the improved local control on survival. However, the prostate specific antigen (PSA) levels could provide an indication at 5 years, 17% of the neutron patients showed elevated PSA levels compared to 45% for the photon patients (P<0.001). 

T raditionally, milk thistle fruits have been used for disorders of the liver, spleen, and gall bladder, such as jaundice and gall bladder colic. Milk thistle has also been used for nursing mothers for stimulating milk production, as a bitter tonic, for hemorrhoids, for dyspeptic complaints, and as a demulcent in catarrh and pleurisy. It is stated to possess hepatoprotective, antioxidant, and choleretic properties (128). Current interest is focused on the hepatoprotective activity of milk thistle and its use for the treatment of liver, spleen, and gall bladder disorders (129). Recently it has been shown that silibinin reduced prostate-specific antigen levels in prostate carcinoma cells lines, indicating a possible role of silibinin in human prostate cancer (130,131). 

Zi X, Agarwal R. Silibinin decreases prostate-specific antigen with cell growth inhibition via G1 arrest, leading to differentiation of prostate carcinoma cells implications for prostate cancer intervention. Proc Natl Acad Sci USA 1999 96 7490-7495. 

Trials of therapeutic vaccination against prostate cancer used OncoVax-P (Jenner Biotherapies, Inc, San Ramon, California). OncoVax-P consists of 200 pg monophosphoryl lipid A (similar to that used in Detox) added to 1 ml liposomes and 100 pg PSA (prostate-specific antigen). Patients received injections by different routes (intramuscular, intravenous or subcutaneous) according to the trial, with or without GM-CSF, IL-2 or BCG and cyclophosphamide pretreatment. No serious side effects were seen. DTH and antibody responses were achieved. Vaccination increased the PSA-reactive T cell frequency as determined by IFN-y secretion, but no toxicity against PSA-expressing target cells was detected. The most effective strategy could not be determined, and no conclusion about the clinical efficacy of the treatment was possible [214,215],... 

The effect of adding finasteride 5 mg/day to high-dose bicalutamide 150 mg/ day has been studied in 41 men with advanced prostate cancer treated over a mean of 3.9 years (21). The serum prostate-specific antigen (PSA) concentration was measured every 2 weeks until disease progression. At the first nadir of PSA, the median fall from baseline was 96.5% a second nadir occurred in 30 of 41 patients, with a median fall of 98.5% from baseline. The median times to each nadir were 3.7 and 5.8 weeks respectively. The median time to treatment failure was 21 months. Adverse effects were minor, including gynecomastia. Sex drive was normal in 17 of 29 men at baseline and in 12 of 24 men at the second PSA nadir, but one-third of the men had spontaneous erections at both times. The authors concluded that finasteride provided additional intracellular androgen blockade when added to bicalutamide. The duration of control was comparable to that achieved with castration, with preserved sexual function in some patients. 

Finasteride reduces serum prostate-specific antigen concentrations (60). In participants in the Prostate Cancer Prevention Trial who had an end of study biopsy (928... 

Etzioni RD, Howlader N, Shaw PA, Ankerst DP, Penson DF, Goodman PJ, Thompson IM. Long-term effects of finasteride on prostate specific antigen levels results from the prostate cancer prevention trial. J Urol 2005 174(3) 877-81 [erratum 2071]. 

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