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)

This paper reviews basic and clinical aspects of human prostate cancer, with special regard to steroid hormones and growth factors, their receptors and the use of these tools in clinical practice. Unlike other endocrine-related tumours, such as breast and endometrial cancer, human prostatic carcinoma has distinctive features that crucially hinder its definition in terms of both biological potential and clinical course. Failure of androgen receptors to represent helpful discriminants for both prognosis and treatment of prostate cancer patients may depend upon methodological pitfalls and/or the heterogeneous composition of most tumour tissues. The former involve either technical problems (tissue sampling and storage, assay procedures) or biochemical and biological points (heterogeneity and functional integrity of steroid binding sites, subcellular and tissue distribution of steroid receptors). The latter mostly concern the unique feature of both normal and diseased prostate gland to present regional diversities in hormone sensitivity and steroid receptor content. Another important area of interest resides in the potential role played by stromal-epithelial interaction in the regulation of growth and function of prostate epithelial cells. In this respect, continued growth of androgen-dependent prostate cancer cells is achieved through intricate pathways where mesenchymal steroid-induced polypeptide growth factors may act in a paracrine/autocrine fashion to mediate androgen action on tumor epithelial cells. In particular, epidermal growth factor (EGF) and transforming growth factor-a (TGFa) may serve as androgen intermediaries in the proliferative control of prostate epithelial cells, but may also be involved in androgen-independent autocrine epithelial cell growth. Clinical correlations of androgen receptors in human prostatic carcinoma have been insofal disappointing. Biochemical or histochemical assays have failed to satisfactorily predict prognosis and response to endocrine therapies of patients. This recalls problems in both methodologies and tissue suitability and points to the need of prolonged follow-up studies wherein special care is placed in sampling conditions, identification of high-affinity sites of steroid binding and selection of threshold values for receptor concentrations. Assay of the EGF receptors might provide additional contribution for a deeper inspection of the biological nature of prostate tumour tissues and help in selecting more appropriate individual-based therapeutic strategies.
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PMID:Steroid receptors in prostate cancer tissues and cells: pathophysiology, problems in methodology, clinical value and controversial questions. 800 81

Elevated levels of epidermal growth factor (EGF) and epidermal growth factor receptor (EGF-R) have been demonstrated in prostate cancer cell lines and clinical specimens suggesting a role for polypeptide growth factors in prostate tumor cell growth and invasion. To more clearly define the role of EGF in prostate cancer invasion, we undertook a series of studies utilizing the PC3 prostate cancer cell line, an aggressive, hormone-independent cell line derived from a metastatic lesion. No statistical differences were noted in the growth of PC3 cells under serum-free conditions when EGF (10(-10) M-10(-8) M) or monoclonal anti-EGF-R antibody (10(-11) M-10(-8) M) were added. Utilizing the Boyden chamber microinvasion assay, EGF supplemented cells demonstrated a statistically significant augmentation in invasion (P < 0.05) when compared to control cells at each time point in the study. With increasing length of exposure to EGF, the number of concentrations that produced significant invasion increased: day 1 (10(-8) M), day 3 (10(-8), 10(-9) M), and day 5 (10(-7), 10(-8), 10(-10) M). Northern blot analysis of EGF supplemented cells revealed an increase in expression of urokinase plasminogen activator (uPA) RNA, a serine protease involved in the regulation of pericellular proteolysis and membrane degradation. Protein analysis confirmed these findings. Statistically significant inhibition of invasion by anti-uPA antibodies was demonstrated for EGF-stimulated and PC3 control cells. Our results demonstrate that certain concentrations of EGF augment invasion in the PC3 cell line. This enhancement of invasion occurs in part by an overproduction of uPA, an extracellular protease. These findings suggest that the autocrine production of EGF may potentiate tumor cell invasion.
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PMID:Effect of epidermal growth factor on prostate cancer cell line PC3 growth and invasion. 829 Mar 89

Growth of the prostate is controlled by androgen. However, there is information indicating that androgen may not act directly, but may act indirectly through polypeptide growth factors, to control prostate growth. This review will focus on the involvement of members of the fibroblast growth factor (FGF) family in this process. The properties of FGFs and FGF-receptors are described that implicate these molecules in growth control. Information is provided that prostate stromal cells synthesize FGF2 and FGF7. FGF2 is a potent mitogen for stromal cells; whereas, FGF7 is exclusively a mitogen for epithelial cells. Transforming growth factor beta (TGF beta), also produced by prostate cells, inhibit cell growth. This suggests that prostate growth is controlled by autocrine and paracrine mechanisms. Evidence is presented that altered FGF expression accompanies benign prostatic hyperplasia and prostate cancer. A model is proposed whereby androgen regulates TGF beta, influencing FGF2 and FGF7 expression, and in turn regulating growth of the prostatic stroma and epithelium. An imbalance in the influence of these growth factors may contribute to prostate disease.
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PMID:Regulation of prostate growth by fibroblast growth factors. 858 Oct 1

Serum tissue polypeptide antigen (TPA) was measured using a newly developed Prolifigen TPA-M "Daiichi" kit in 1,236 healthy subjects, 2,867 patients with malignant tumors, and 901 with benign diseases. Because 94.0% of healthy subjects had serum TPA under 70 U/l, the cut-off value was set at 70 U/l. Serum TPA was elevated in more than 50% of patients with head and neck cancer, lung cancer, liver cancer, gallbladder or bile duct cancer, pancreatic cancer, colorectal cancer, ovarian cancer, and prostate cancer. The overall positive rate in malignant tumors was 55.5%. Serum TPA was higher in advanced cancer than in earlier stage cancer, and decreased after the resection of the tumor. The false positive rate in benign diseases was 31.3%. ROC analysis revealed the usefulness of TPA as a tumor marker in many cancers. The correlation coefficient between TPA and CYFRA 21-1, and between TPA and TPSA, was 0.747 and 0.694, respectively. In conclusion, measurement of serum TPA using the new kit is useful in the management of patients with various malignant tumors.
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PMID:[Measurement of serum tissue polypeptide antigen (TPA) in patients with malignant tumor using prolifigen TPA-M "Daiichi" kit]. 864 25

Polypeptide growth factors are positive and negative regulators of prostatic growth and function. Expression and biological effects of epidermal growth factor (EGF), transforming growth factors (TGFs) alpha and beta, fibroblast growth factors (FGFs), and insulin-like growth factors (IGFs) in the prostate have been extensively studied. EGF and TGF alpha, which share the same receptor, are strong mitogens for prostatic epithelial and stromal cells. Their paracrine mode of action in normal tissue and early-stage tumors is apparently altered towards an autocrine stimulation in hormone-independent tumors, which gain the ability to produce TGF alpha by themselves. TGF beta has a dual role in the regulation of prostatic growth. It inhibits growth of prostatic epithelial cells in culture and mediates programmed cell death after androgen withdrawal. However, advanced prostatic carcinomas become insensitive to the inhibitory effect of TGF beta. Several members of the FGF family have been identified in the prostate. They are mainly or exclusively expressed in the stromal cells, and stimulate the epithelial cells. In the rat Dunning tumor model, progression is accompanied by distinct changes in the expression of FGFs and their receptors. In the hyperplastic tissue, basic FGF (bFGF) is accumulated. This growth factor is also a potent angiogenic inducer, expression of which may determine the metastatic capability of a tumor. IGFs are paracrine growth stimulators in the normal and hyperplastic prostate. It is still under consideration whether prostatic cancer cells gain the ability to produce IGF-I by themselves and thus shift to an autocrine mode of IGF-I stimulation. Growth factors also interact with the androgen-signaling pathway. IGF-I in particular, other growth factors as well, can activate the androgen receptor.
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PMID:Regulation of prostatic growth and function by peptide growth factors. 865 77

Several serum tumor markers have been studied in different types of epithelial cell-associated cancer. The application of these markers in clinical oncologic practice is hampered by insufficient sensitivity and specificity in most primary tumors. It is important to define which markers contribute to patient management. Prostate-specific antigen can be used in prostate cancer patients for screening and monitoring advanced disease. Cancer antigen 125 is primarily used for the monitoring of combined chemotherapy in ovarian cancer patients. In breast cancer patients preoperative levels of cancer antigen 15-3, carcinoembryonic antigen, and tissue polypeptide antigen specific do not contribute in prognosis, but changes in the levels of these markers predict the clinical outcome in the treatment of advanced disease better than UICC criteria. Carcinoembryonic antigen and tissue polypeptide antigen specific can detect recurrence in colorectal cancer patients earlier than imaging methods. Tissue polypeptide antigen specific is sensitive in measuring response to combined chemotherapy in advanced gastrointestinal cancer. In bladder cancer, urine levels of cytokeratins are sensitive in indicating advanced disease. In small-cell lung cancer neuron-specific enolase is a good indicator of chemotherapy response. In non-small-cell lung cancers, cytokeratins may also predict response in chemotherapy treatment. Clinical application of tumor markers in the correct circumstances can omit more invasive and costly procedures and will contribute to better patient care.
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PMID:How to integrate serum tumor markers into clinical oncologic practice. 874 5

The present study evaluated serial serum measurements of tissue polypeptide-specific antigen (TPS) in comparison with prostate-specific antigen (PSA) for assessment of tumour progression in patients with advanced prostate cancer receiving intermittent androgen suppression therapy (IAS). Twenty-three men were recruited into an IAS trial consisting of an initial 8 months of androgen suppression, followed by cycles of treatment cessation and resumption of therapy upon increases of PSA > 20 ng ml(-1) to prolong the hormone responsiveness of the tumour cells. Periods of androgen suppression resulted in reversible reduction in serum testosterone (< 1.8 nmol I(-1)) and PSA (< 4 ng ml(-1)) and decreases in tumour volume (mean reduction for first cycle 24 +/- 10%), indicating partial growth arrest and apoptotic regression of the tumours. In contrast to PSA values, non-specifically elevated TPS values were found in 8 of 23 patients. In 15 of 23 patients, TPS fell during periods of apoptotic tumour regression and increased simultaneously with testosterone and preceded the increases in PSA by 2 months during the period of treatment cessation. Although TPS represents a highly sensitive marker of tumour proliferation in this IAS clinical model of controlled tumour regression and regrowth, its low specificity compared with PSA limits its usefulness to monitoring of prostate cancer patients with proven absence of non-specific elevations of this marker.
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PMID:Measurements of tissue polypeptide-specific antigen and prostate-specific antigen in prostate cancer patients under intermittent androgen suppression therapy. 916 47

The long term goal of this study is to develop autoimmune prostatitis as a therapy for prostate cancer. An immune attack capable of destroying normal prostate epithelial cells should also destroy malignant prostate tissue and provide therapeutic benefit in cancer patients. The current study was initiated to identify antigenic targets for experimental autoimmune prostatitis on the assumption that such proteins might also be suitable targets for immunotherapy of prostate cancer. Male Lewis rats were immunized with syngeneic prostate homogenates, and the immune sera were used to screen prostate proteins for immunoreactivity by Western blot analysis. The dominant protein recognized by the immune sera was purified by ion exchange chromatography and reverse phase HPLC. Microsequence analysis of two polypeptide components of this immunodominant protein demonstrated N-terminal sequences identical with two of the three component chains of rat prostatic steroid-binding protein (PSBP). T cell responses to PSBP were also detected in rats immunized with prostate homogenate. Immunizing male rats with purified PSBP induced vigorous Ab and T cell responses. Significant prostate inflammation was observed in some rats immunized with PSBP. Adoptive transfer of T cells immune to PSBP induced rapid and severe destructive autoimmune prostatitis. These results demonstrate that PSBP is a major target Ag of experimental autoimmune prostatitis in a rat model and may serve as a target Ag for vaccine and T cell therapy against prostate cancer.
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PMID:Identification of rat prostatic steroid-binding protein as a target antigen of experimental autoimmune prostatitis: implications for prostate cancer therapy. 920 Apr 88

The therapeutic and prognostic significance of androgen receptors in prostatic carcinoma has been examined on the basis of data obtained with the different techniques used in receptor determination. Moreover, the role of some polypeptide growth factors in the regulation of prostatic cancer growth and progression has been reviewed. Great attention has been focused on in vitro models utilized to investigate androgen receptor alterations and the effects of the different positive and negative regulators of prostatic carcinoma cell growth.
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PMID:[Hormone receptors and growth factors in carcinoma of the prostate]. 941 97

The effects of pituitary adenylyl cyclase activating polypeptide (PACAP) analogs on prostate cancer cell lines was investigated. 125I-PACAP-27 bound with high affinity to PC-3 cells (Kd = 10 nM) to a single class of sites (Bmax = 30000/cell). By RT-PCR, a major 305 bp band was observed using cDNA derived from PC-3, LNCaP or DU-145 cells. Specific 125I-PACAP binding was inhibited with high affinity by PACAP-27, PACAP-38 and PACAP(6-38) (IC50 values of 15, 10 and 300 nM, respectively) but not by PACAP(28-38). PACAP elevated cAMP and the increase caused by PACAP-27 was reversed by PACAP(6-38). PACAP transiently increased c-fos gene expression and the increase in c-fos mRNA was reversed by PACAP(6-38). PACAP-27 stimulated colony formation in PC-3 cells, whereas PACAP(6-38) reduced colony number and size. In nude mice bearing PC-3 xenografts, PACAP(6-38) significantly slowed tumor growth. These data suggest that biologically active type 1 PACAP receptors are present on human prostate cancer cells and that prostate cancer cell growth is inhibited by PACAP(6-38).
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PMID:PACAP(6-38) inhibits the growth of prostate cancer cells. 956 7


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