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)

The Dunning tumor, originally described as a carcinoma of the rat dorsal prostate, has for long been used as an experimental model of prostatic cancer. We have recently presented a number of morphological findings that are incompatible with the prostatic origin of the H-subline of the Dunning tumor. In this paper, biochemical and immunohistochemical markers of rat prostate and mammary gland are studied in the R-3327 Dunning H tumor. Pieces of the H tumor were inoculated in male or lactating female rats. The electrophoretic protein pattern of Dunning tumor extracts was more similar to that of the mammary gland than the dorsolateral prostate. Proteins selectively appearing after metabolic labeling in Dunning tumors grown in lactating rats corresponded to labeled proteins in mammary glands from the same animals. Secretory proteins typical of the lateral prostate (SVS II) and dorsal prostate (transglutaminase) could not be detected immunohistochemically in the Dunning tumor. Western blot studies of tumor extracts and slot blot analysis of RNA preparations from the tumor confirmed the absence of SVS II and prostate specific transglutaminase from the Dunning tumor. On the other hand, the presence of mammary gland proteins such as milk fat globule membrane proteins, lactoperoxidase and lactalbumin were detected in the Dunning tumor by immunohistochemistry and Western blotting, but were absent from the dorsolateral prostate. Transferrin-mRNA, expressed in the male urogenital tract and also in the liver and other tissues, was detected in the mammary gland and Dunning tumor, but not in the dorsolateral prostate. The absence of mammary gland secretory beta-casein in the Dunning tumor was related to the elevated Ha-ras oncogene expression in the tumor, previously reported to suppress casein expression. The findings clearly demonstrate that the prostate cannot be the origin of the Dunning tumor, presently being used in prostatic cancer research. The designation prostatic adenocarcinoma for this tumor is therefore invalid. Furthermore, the data support our view that mammary gland might be the origin of the Dunning tumor, although the derivation from the bulbourethral or the parotid glands cannot strictly be excluded.
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PMID:Arguments against the prostatic origin of the R-3327 Dunning H tumor. 135 78

Calcium (Ca2+) accumulates within the endoplasmic reticulum of cells through function of the sarcoplasmic reticulum and endoplasmic reticulum Ca(2+)-dependent ATPase family of intracellular Ca(2+)-pumping ATPases. The resulting pools have important signaling functions. Thapsigargin (TG) is a sesquiterpene gamma-lactone which selectively inhibits the sarcoplasmic reticulum and endoplasmic reticulum Ca(2+)-dependent ATPase pumps with a 50% inhibitory concentration of approximately 30 nM. Treatment of androgen-independent prostate cancer cells of both rat and human origin with TG inhibits their endoplasmic reticulum Ca(2+)-dependent ATPase activity, resulting in a 3-4-fold elevation in the level of intracellular free Ca2+ (Cai) within minutes of exposure. Due to a secondary influx of extracellular Ca2+, this increase in Cai is sustained, resulting in morphological (cell rounding) and biochemical changes within 6-12 h (enhanced calmodulin, glucose regulated protein, and tissue transglutaminase expression, and decreased expression of the G1 cyclins). Within 24 h of exposure, androgen-independent prostatic cancer cells stop progression through the cell cycle, arrest out of cycle in G0, and irreversibly lose their ability to proliferate with a median effective concentration value of 31 nM TG. During the next 24-48 h, the genomic DNA of the G0-arrested cells undergoes double-strand fragmentation. This is followed by the loss of plasma membrane integrity and fragmentation of the cell into apoptotic bodies. During this process, there is no acidification in the intracellular pH. Using cells transfected with the avian M(r) 28,000 calbindin D Ca(2+)-buffering protein, it was demonstrated that the programmed death initiated by TG is critically dependent upon an adequate (i.e., 3-4-fold) sustained (> 1 h) elevation in Cai and not depletion of the endoplasmic reticulum pools of Ca2+. These results demonstrate that TG induces programmed cell death in androgen-independent prostatic cancer cells in a dose-dependent manner and that this death does not require proliferation or intracellular acidification but is critically dependent upon an adequate, sustained (i.e., > 1 h) elevation in Cai.
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PMID:The role of calcium, pH, and cell proliferation in the programmed (apoptotic) death of androgen-independent prostatic cancer cells induced by thapsigargin. 795 63

Androgen-independent Dunning R-3327 AT-3 rat prostatic cancer cells can be induced to undergo programmed cell death in either a proliferation-dependent or independent manner depending upon the therapeutic agent used. In the present study, 5-fluorodeoxyuridine (5-FrdU) was used to induce proliferation-dependent death of the AT-3 cells via its ability to inhibit thymidylate synthetase. Ionomycin and thapsigargin were used to induce proliferation-independent death of these cells via their ability to sustain an elevation in intracellular free Ca2+. Based upon the temporal sequence of DNA fragmentation, morphologic changes, and loss of cell viability, each of the three test agents, at the doses used, induces the programmed death of AT-3 cells with essentially identical kinetics. Based upon these similarities, comparisons of the pattern of gene expression during the proliferation-dependent (i.e., 5-FrdU-induced) vs. proliferation-independent (i.e., ionomycin and thapsigargin-induced) programmed death of AT-3 cells allow identification of genes whose enhanced expression is involved in the initiation vs. completion of programmed cell death. Based upon this approach, enhanced H-ras and TRPM-2 expression is associated with initiation of proliferation-dependent programmed death of AT-3 cells while enhanced c-myc, calmodulin, and alpha-prothymosin expression is associated with initiation of proliferation-independent programmed death of these cells. In contrast, enhanced expression of glucose-regulated 78 kilodalton and tissue transglutaminase genes are associated with the completion of programmed cell death, since their expression is enhanced in both proliferation-dependent and independent programmed cell death of AT-3 cells.
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PMID:Proliferation-dependent vs. independent programmed cell death of prostatic cancer cells involves distinct gene regulation. 799 34

Transglutaminases with different functions and tissue distribution patterns can be distinguished by specific antibodies and by inhibition of enzyme activity in the presence of guanosine triphosphate (GTP). The most common form is the so-called tissue-type transglutaminase that is apparently involved in membrane stabilization processes, e.g. during apoptosis, and can be inhibited by incubation with GTP at low calcium concentrations. A secretory transglutaminase that cannot be inhibited by GTP is synthesized in an androgen-dependent manner in the dorsal prostate of the rat, the site suggested to represent the origin of the Dunning tumor used as an experimental model in prostate cancer research. Here we studied the expression of transglutaminases in different Dunning tumor lines--mainly in the highly differentiated H subline--and characterized the enzyme both biochemically and immunocytochemically. A very high enzyme activity was found only in the less well differentiated HI-F tumor line. Immunohistochemical reactions and Western blot analysis showed that there is no secretory transglutaminase present in any of the Dunning tumor lines studied. Transglutaminase activity of the Dunning tumor results from the so-called tissue-type enzyme that is non-organ specific. The absence of a secretory form of transglutaminase does not support the contention of a prostatic origin of the Dunning tumor.
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PMID:Tissue-type transglutaminase expression in the Dunning tumor. 809 3

Non-small cell lung cancer (NSCLC) is fatal in approximately 90% of all cases due to the failure of systemic therapy, secondary to resistance to chemotherapy. In such malignancies new therapeutic paradigms are needed. One such approach takes advantage of normal physiologic growth regulatory mechanisms, such as terminal cellular differentiation or apoptosis. Suramin, as an antineoplastic drug, has shown efficacy in the treatment of prostate cancer and is capable of promoting differentiation in several human cancer cell lines. Little is known about the differentiating effects of suramin in lung cancer. In the present investigation we evaluated the ability of suramin to induce cross-linked envelope (CLE) formation, as a common marker for squamous differentiation and apoptosis, in three representative human non-small cell lung cancer cell lines: NCI-H226 (squamous), NCI-H358 (bronchoalveolar [adenocarcinoma]), and NCI-H596 (adenosquamous). Among agents that we have tested, suramin demonstrated the unique ability to induce spontaneous CLE formation in the two cell lines with squamous features, NCI-H226 and NCI-H596. Suramin induced CLE formation was accompanied by DNA fragmentation, a marker for apoptosis, in NCI-H596 and NCI-H358, but not in NCI-H226. Stimulation of CLE formation by suramin correlated with the rapid induction of both type II transglutaminase (TG) activity and involucrin expression. These parameters were protein synthesis independent, suggesting posttranslational mechanisms of suramin activity. Induction of differentiation/apoptosis markers by suramin did not correlate with its effect on growth. Modulation of signal transduction is a likely candidate mechanism for suramin activity in lung cancer. The relationship between growth, squamous differentiation, and apoptosis is considered.
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PMID:Effect of suramin on squamous differentiation and apoptosis in three human non-small-cell lung cancer cell lines. 880 1

Using biochemical assays, we compared enzyme activities with the immunoreactivity of antibodies against rat seminal transglutaminase (TGase), human erythrocyte TGase and guinea pig liver TGase in human normal prostate, primary prostatic carcinomas and prostatic carcinoma cell lines. Glandular cells of the epithelium were only exceptionally positive with the antibody against (rat) secretory TGase. Using the antibodies against tissue-type TGase, most immunoreactive cells were found in the basal cell layer of prostatic epithelium as well as in stroma (fibroblasts, endothelial cells), whereas immunoreactive glandular cells were sparse. In the case of benign prostatic hyperplasia, few, irregularly distributed secretory cells along with a small number of stromal cells were also immunoreactive with the tissue-type TGase antibody. In dedifferentiated carcinomas, immunoreactive cells were nearly completely absent. Of the prostate cancer cell lines, the LNCaP line showed neither TGase enzyme activity nor immunoreactivity, whereas the PC-3 cell line displayed significant enzyme activity and immunoreactivity. No hormone-dependent changes in either enzyme activity or immunoreactivity were recorded after in vitro treatment of the respective cell lines with estrogens, androgens and antiandrogens. As there is no correlation between androgen deprivation and TGase expression in nonmalignant and malignant human prostatic epithelial cells, TGase activity more likely indicates cellular lesions and consecutive repair mechanisms.
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PMID:Immunological characterization and activity of transglutaminases in human normal and malignant prostate and in prostate cancer cell lines. 883 86

Human prostate-specific transglutaminase (hTGP) is a cross-linking enzyme secreted by the prostate. In this study, we performed dot blot analysis of 50 normal human tissues to demonstrate unambiguously the prostate-specific expression of hTGP. Furthermore, we elucidated the genomic organization of the TGM4 gene, the gene encoding hTGP. The structure of this gene displays striking similarity to that of other transglutaminase (TGase) genes. The TGM4 gene spans approximately 35 kb of genomic DNA and consists of 13 exons and 12 introns. The main transcription initiation site is located 52 bp upstream of the translational start codon. A hTGP splice variant of intron 1 was detected. This splice variant contains an in-frame antisense Alu element insertion. The TGM4 promoter was analyzed by sequencing and transfection experiments. At positions -1276 to -563, the promoter harbors a cyclophilin pseudogene with 94% similarity to the cyclophilin A cDNA. Deletion mapping of the TGM4 promoter in the transiently transfected human prostate cancer cell line PC346C showed comparable activity of 2.1-, 1.5-, and 0.5-kb promoter fragments.
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PMID:The human prostate-specific transglutaminase gene (TGM4): genomic organization, tissue-specific expression, and promoter characterization. 972 Dec 14

We treated primary epithelial cells from human normal prostate (NEPC) and prostate cancer (CEPC) with all-trans-retinoic acid (RA) to study whether it regulates the activity of tissue transglutaminase (tTGase), an enzyme that accumulates in cells undergoing apoptosis. tTGase activity was assessed by [14C]spermidine incorporation; tTGase, P53, Bcl-2, and p21 protein levels were evaluated by Western blotting; and RA receptors (RAR alpha, -beta, and -gamma), tTGase, retinol-binding protein (RBP), and cellular RBP type I transcripts were determined by semiquantitative RT-PCR. After 72-96 h of 10(-6) mol/L RA treatment, cell growth inhibition and apoptosis were associated with increased tTGase activity in both NEPC and CEPC, and with increased tTGase protein and messenger ribonucleic acid levels only in NEPC. Moreover, RA down-regulated RAR alpha and -beta and increased RBP messenger ribonucleic acid levels in NEPC, whereas it increased RAR beta gene expression and decreased Bcl-2 protein levels in CEPC. Our results suggest that RA induces tTGase gene expression and enzyme activity in normal prostate cells, and that RA-regulated pathways are impaired in cancer cells. Moreover, down-regulation of Bcl-2 protein and up-regulation of RAR beta suggest that retinoid may act on the genetic defect responsible for prostate cancer progression.
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PMID:Changes in tissue transglutaminase activity and expression during retinoic acid-induced growth arrest and apoptosis in primary cultures of human epithelial prostate cells. 1019 96

We have previously described that tissue transglutaminase (tTG) is a high level phenotypic biomarker in prostate cancer, which is down regulated in prostate cancer and surrounding premalignant field compared to benign prostate glands. To understand the function of tTG in prostate cancer, we sought to identify proteins that interact with the transglutaminase moiety of tTG using a human prostate cancer complementary deoxyribonucleic acid library in a Yeast 2-Hybrid system. The Yeast 2-Hybrid experiments identified a strong and novel interaction between the transglutaminase moiety and protein kinase A anchor protein 13 (AKAP13), which was quantified by beta-galactosidase assay, confirmed in vitro by immunoprecipitation experiments using PC3 prostate cancer cell lysates, and in vivo colocalization was confirmed by immunofluorescence studies in PC3 cells. Because AKAP plays a major role in protein kinase A and Rho protein mediated signaling, functional studies are underway to elucidate the significance of tTG-AKAP13 interaction in prostate cancer.
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PMID:Tissue transglutaminase interacts with protein kinase A anchor protein 13 in prostate cancer. 1630 Nov 18

The prostate transglutaminase, TGase-4, is a member of the transglutaminase family and is uniquely expressed in the prostate gland. The function of the protein is largely unknown, although an influence on cell motility and adhesion has been indicated. The present study investigated the impact of the differential expression of TGase-4 in human prostate cancer cells on RON, the hepatocyte growth factor-like/macrophage-stimulating protein (HGF-L/MSP) receptor, mediated cellular functions. Using human prostate cancer cell lines and prostate tissues, we demonstrated that human TGase-4 had a high degree of co-localisation with RON, primarily at the cell periphery and cell-cell adhesion region. High levels of TGase-4 expression in CAHPV10 cells and in PC3 cells engineered to over-express TGase-4 were associated with significantly increased cell motility in response to HGF-L, a clear contrast to wild-type and control cells. Neutralising antibody to RON and rhHGFL/MSP had no further bearing on the increased motility in TGase-4 over-expressing cells, although they had profound effect on the control cells. Akt pathway inhibitor significantly diminished the effect induced by HGF-L in the cells. Finally, over-expression of TGase-4 in prostate cancer cells resulted in autophosphorylation of RON. It is concluded that TGase-4 expression is intrinsically linked to the activation of RON in prostate cancer cells and that this autoactivation of RON contributes to the increased cell motility in TGase-4 expressing cells.
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PMID:The prostate transglutaminase, TGase-4, coordinates with the HGFL/MSP-RON system in stimulating the migration of prostate cancer cells. 2059 68


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