| 1. |
- Adamo, Hanibal Hani, 1984-, et al.
(author)
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Prostate cancer induces C/EBPβ expression in surrounding epithelial cells which relates to tumor aggressiveness and patient outcome
- 2019
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In: The Prostate. - : John Wiley & Sons. - 0270-4137 .- 1097-0045. ; 79:5, s. 435-445
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Journal article (peer-reviewed)abstract
- Background: Implantation of rat prostate cancer cells into the normal rat prostate results in tumor-stimulating adaptations in the tumor-bearing organ. Similar changes are seen in prostate cancer patients and they are related to outcome. One gene previously found to be upregulated in the non-malignant part of tumor-bearing prostate lobe in rats was the transcription factor CCAAT/enhancer-binding protein- (C/EBP).Methods: To explore this further, we examined C/EBP expression by quantitative RT-PCR, immunohistochemistry, and Western blot in normal rat prostate tissue surrounding slow-growing non-metastatic Dunning G, rapidly growing poorly metastatic (AT-1), and rapidly growing highly metastatic (MatLyLu) rat prostate tumors?and also by immunohistochemistry in a tissue microarray (TMA) from prostate cancer patients managed by watchful waiting.Results: In rats, C/EBP mRNA expression was upregulated in the surrounding tumor-bearing prostate lobe. In tumors and in the surrounding non-malignant prostate tissue, C/EBP was detected by immunohistochemistry in some epithelial cells and in infiltrating macrophages. The magnitude of glandular epithelial C/EBP expression in the tumor-bearing prostates was associated with tumor size, distance to the tumor, and metastatic capacity. In prostate cancer patients, high expression of C/EBP in glandular epithelial cells in the surrounding tumor-bearing tissue was associated with accumulation of M1 macrophages (iNOS+) and favorable outcome. High expression of C/EBP in tumor epithelial cells was associated with high Gleason score, high tumor cell proliferation, metastases, and poor outcome.Conclusions: This study suggest that the expression of C/EBP-beta, a transcription factor mediating multiple biological effects, is differentially expressed both in the benign parts of the tumor-bearing prostate and in prostate tumors, and that alterations in this may be related to patient outcome.
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| 2. |
- Babiker, Adil A., et al.
(author)
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Mapping pro- and antiangiogenic factors on the surface of prostasomes of normal and malignant cell origin
- 2010
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 70:8, s. 834-847
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Journal article (peer-reviewed)abstract
- BACKGROUND: Angiogenesis is the formation of new blood vessels by capillary sprouting from pre-existing vessels. Tumor growth is angiogenesis-dependent and the formation of new blood vessels is associated with the increased expression of angiogenic factors. Prostasomes are secretory granules produced, stored and released by the glandular epithelial cells of the prostate. We investigated the expression of selected angiogenic and anti-angiogenic factors on the surface of prostasomes of different origins as well as the direct effect of prostasomes on angiogenesis. METHODS: VEGF, endothelin-1, endostatin, and thrombospondin-1 were determined on prostasomes from seminal fluid and human prostate cancer cell lines (DU145,PC-3,LNCaP) using different immunochemical techniques. Human dermal microvascular endothelial cells were incubated with seminal and DU145 cell-prostasomes and with radioactive thymidine. The effect of prostasomes on angiogenesis was judged by measuring the uptake of labeled thymidine. The presence of any deleterious effects of prostasomes on the endothelial cells was investigated using thymidine assay and confocal laser microscopy. RESULTS: VEGF and endothelin-1 were determined on malignant cell-prostasomes (no difference between cell lines) but not determined on seminal prostasomes. The same applies for the expression of endostatin but with much higher expression on malignant cell-prostasomes with obvious differences between them. Seminal and DU145 cell-prostasomes were found to have anti-angiogenic effect which was more expressed by DU145 cell-prostasomes. No deleterious effect of prostasomes on endothelial function was detected using either thymidine assay or microscopy. CONCLUSIONS: Prostasomes contain pro- and anti-angiogenic factors that function to counteract each other unless the impact from one side exceeds the other to bring about dysequilibrium.
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| 3. |
- Babiker, Adil A., et al.
(author)
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Overexpression of ecto-protein kinases in prostasomes of metastatic cell origin
- 2006
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 66:7, s. 675-686
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Journal article (peer-reviewed)abstract
- BACKGROUND:Prostasomes are secretory granules produced, stored, and released by the glandular epithelial cells of the prostate. They express numerous enzymes whose physiological roles have so far not been fully evaluated. In this study, we investigated the expression and function of prostasomal protein kinases and ATPase.METHODS:The protein kinase activities of prostasomes isolated from seminal fluid and malignant prostate cell lines (PC-3, DU145, and LNCaP) were investigated using the model phosphorylation substrates histone and casein, as well as the plasma proteins C3 and fibrinogen, in combination with specific protein kinase inhibitors. The prostasomal ATPase activity was also evaluated. The expression of protein kinases and ATPase on prostasomes was verified by flow cytometry.RESULTS:Prostasomes (intact or solubilized with octylglucoside or saponin) from prostate cancer cells had higher expression of protein kinases A, C, and casein kinase II compared to prostasomes isolated from seminal plasma, resulting in higher phosphorylation of both exogenous and endogenous substrates. Using intact prostasomes, it was found that prostasomes of metastatic origin had lower ATPase activity, resulting in higher residual ATP available for the phosphorylation reaction. Finally, complement component C3 and fibrinogen (two proteins whose activities are modulated by phosphorylation) were identified as physiologically relevant phosphorylation substrates.CONCLUSIONS:These results indicate that prostasomes are capable of modifying proteins possibly involved in the innate response by extracellular phosphorylation mediated by ecto-kinases. This is a novel mechanism by which prostatic malignant cells may interact with their environment.
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| 4. |
- Babiker, Adil A., et al.
(author)
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Prothrombotic effect of prostasomes of metastatic cell and seminal origin
- 2007
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 67:4, s. 378-388
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Journal article (peer-reviewed)abstract
- BACKGROUND. Prostasomes are secretory granules produced by the glandular epithelial cells of the prostate. Seminal prostasomes contain high amounts of Tissue Factor (TF) but no studies of TF on malignant cell prostasomes have been made. Here we compare the expression, phosphorylation, and function of TF on prostasomes of different origin. METHODS. TF was detected on prostasomes isolated from seminal fluid and human prostate cancer cell lines (PC-3, DU145, and LNCaP) using FACS and enzyme immunoassay (EIA). Incubation of prostasomes with radioactive ATP under conditions favoring protein kinase A activity led to phosphorylation of TF as detected by immunoprecipitation and SDS-PAGE. The prothrombotic effect of prostasomes was investigated in whole blood and recalcified plasma. Blocking experiments were performed using anti-TF antibodies and corn trypsin inhibitor. RESULTS. TF was expressed on all tested prostasome preparations with lowest values found for seminal ones. Prostasomal TF was the main endogenous substrate for prostasomal protein kinase A. All tested prostasome preparations greatly enhanced the rate of clot formation in a dose-dependent fashion, that is, the clotting capability of prostasomes seemed to be related to the extent of their expression of TF. In addition, the density of the clot varied between different prostasome preparations. When incubated in whole blood, prostasomes were found to associate to WBC thereby inducing them to express and release TF. CONCLUSIONS. These data show that TF is overexpressed and also subjected to phosphorylation by malignant cell prostasomes. This suggests major roles for prostasomes in thrombotic events that occur in some advanced cases of prostate cancer.
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| 5. |
- Babiker, Adil A., et al.
(author)
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Transfer of functional prostasomal CD59 of metastatic prostatic cancer cell origin protects cells against complement attck
- 2005
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 62:2, s. 105-114
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Journal article (peer-reviewed)abstract
- BACKGROUND: Prostasomes are secretory granules produced, stored, and released, by the glandular epithelial cells of the prostate. They express the glycosylphosphatidylinositol (GPI)-anchored complement regulatory protein CD59, which has been shown to be transferred to spermatozoa and erythrocytes.METHODS: The CD59 content of prostasomes isolated from seminal fluid and malignant prostate cells (PC-3, DU145, and LNCaP) and the transfer of prostasomal CD59 to rabbit erythrocytes (RE) and to PIPLC-treated and unmanipulated cancer cells were investigated using FACS. All prostasomes were also incubated with RE and tested in a hemolytic assay.RESULTS: Prostasomes from cancer cells had higher expression of CD59 than those of normal cells. Prostasomal CD59 of different origin could be transferred to RE, malignant cell lines stripped of CD59 by PIPLC, or unmanipulated LNCaP cells. Malignant cell prostasomes had an increased ability to inhibit complement-mediated lysis compared to those from non-malignant cells.CONCLUSIONS: These results point to a novel mechanism by which prostasomes can protect prostatic malignant cells from complement attack.
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| 6. |
- Beshara, Soheir, et al.
(author)
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Anemia associated with advanced prostatic adenocarcinoma : Effects of recombinant human erythropoietin
- 1997
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In: The Prostate. - 0270-4137 .- 1097-0045. ; 31:3, s. 153-160
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Journal article (peer-reviewed)abstract
- BACKGROUND AND METHODS: Nine patients with hormone-refractory metastatic prostatic adenocarcinoma and anemia were treated with recombinant human erythropoietin (rHuEpo) at a median dose of 150 U/kg BW 3 times a week subcutaneously. Baseline hemoglobin (Hb) ranged from 70 to 116 g/L, and the study duration was 12 weeks (median patient participation period was 8 weeks). RESULTS: Four patients demonstrated a median Hb increase of 20 g/L and were considered responders. Three patients showed a median increase of 17 g/L but required blood transfusion once, and were therefore considered as partial responders. Baseline erythropoietic status showed a significant correlation between serum Epo and Hb. Inadequate Epo production, evaluated by the observed/predicted log Epo ratio, was found in two patients. Defective bone marrow activity, demonstrated by low transferrin receptor (TfR), and hypoferremia in spite of abundant iron stores were also shown. Hemorheological investigations showed elevated plasma viscosity. CONCLUSIONS: Our results indicate that suppression of erythropoiesis can be mainly explained by the depressed marrow activity. The altered hemorheology might contribute to the anemia. This anemia could possibly be corrected with rHuEpo.
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| 7. |
- Carlsson, Björn, et al.
(author)
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Characterization of human prostate and breast cancer cell lines for experimental T cell-based immunotherapy
- 2007
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 67:4, s. 389-395
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Journal article (peer-reviewed)abstract
- BACKGROUND. In order to develop experimental immunotherapy for prostate and breast cancer it is of outmost importance to have representative target cell lines that through human leukocyte antigen (HLA) class I molecules present relevant levels of peptides from tumor-associated antigens for cytotoxic T lymphocyte (CTL) recognition. METHODS. We sequenced the HLA-A and HLA-B loci of eight commonly used prostate and breast cancer cell lines and analyzed the surface expression of HLA-ABC, HLA-DR, CD40, CD80, CD86, and CD54 by flow cytometry. We also analyzed the cell lines for mRNA expression from 25 genes reported to be specifically or preferentially expressed by prostate cells. RESULTS. Among the analyzed cell lines we found that LNCaP, PC-346C and MCF-7 are HLA-A*0201 positive. However, the HLA-A2 expression level is low and only MCF-7 upregulates HLA-A2 in response to IFN-γ stimulation. MCF-7 also expresses high levels of CD54, which further improve its value as a CTL target cell line. On the other hand, LNCaP and PC-346C express 25 and 23 out of 25 prostate-related genes, respectively, while MCF-7 expresses 16 out of 25 genes. CONCLUSIONS. None of the analyzed prostate cancer cell lines are optimal CTL target cells. However, MCF-7 could in many cases be used as a complement to HLA-A*0201 positive prostate cancer cells. The LNCaP and PC-346C cell lines are rich sources of prostate-related antigens that may be valuable for cancer vaccine development.
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| 8. |
- Carlsson, Björn, et al.
(author)
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Generation of cytotoxic T lymphocytes specific for the prostate and breast tissue antigen TARP
- 2004
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 61:2, s. 161-170
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Journal article (peer-reviewed)abstract
- BACKGROUND: Expansion of cytotoxic T lymphocytes (CTL) directed against peptide epitopes from antigens that are specifically expressed by normal and neoplastic prostate epithelial cells has during the last years emerged as an interesting therapeutic approach to treat advanced prostate cancer. TCRgamma alternate reading frame protein (TARP) is a protein that in males is specifically expressed by normal prostate epithelial cells and prostate cancer cells. We have evaluated TARP for human leukocyte antigen (HLA)-A*0201-restricted peptides capable of triggering TARP-specific CTL. METHODS: Dendritic cells (DC) were pulsed either with synthetic peptides derived from the natural amino acid sequence of TARP or with cognate peptides having enhanced affinity for HLA-A*0201 due to an N-terminal anchor residue substitution. The peptide-pulsed DC were used to stimulate autologous T cells ex vivo. RESULTS: We were able to generate T cells against TARP(27-35) and TARP(4-13) and their mutated counterparts TARP(V28L)(27-35) and TARP(P5L)(4-13). The use of affinity-enhanced peptides resulted in the generation of T cells recognizing target cells displaying either wild-type or mutated peptide. We further show that TARP-specific T cells can be tetramer-sorted and subsequently expanded to large numbers by general T cell stimulation, with retained specificity and activity. Sorted and expanded T cells, obtained by stimulation with TARP(P5L)(4-13), exert moderate lysis of the TARP-expressing prostate cancer cell line, LNCaP, and breast cancer cell line, MCF-7, indicating that the TARP(4-13) epitope may be endogenously processed and presented by TARP-positive, HLA-A*0201-positive cells. CONCLUSIONS: Our findings suggest that synthetic TARP peptides, such as TARP(P5L)(4-13), may play a role in prostate and breast cancer immunotherapy.
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| 9. |
- de la Torre, M., et al.
(author)
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Elevated expression of estramustine binding protein (EMBP) in prostatic intraepithelial neoplasia (PIN) compared with malignant and benign prostatic epithelia
- 1994
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In: The Prostate. - 0270-4137 .- 1097-0045. ; 25:3, s. 125-31
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Journal article (peer-reviewed)abstract
- The expression of estramustine-binding protein (EMBP) was studied immunohistochemically in whole-mount prostate sections. Specimens were taken from the prostates of 15 patients who had undergone total prostatectomy due to localized (TOd-T2 NO MO) prostatic cancer (PC). Almost all the examined whole-mount sections displayed areas with prostatic intraepithelial neoplasia (PIN). PIN is regarded as the main precursor of invasive PC. High- and low-grade PIN expressed EMBP. The average positively stained areas accounted for averages of 69.2% and 48.7%, respectively. High-grade PIN contained the highest EMBP levels of all the investigated (benign and malignant) epithelia, followed by moderately differentiated PC. With regard to areas with PC, the highest levels of EMBP expression (61.3%) were observed in moderately differentiated PC; poorly differentiated PC came second. Of all the examined epithelia, EMBP levels were lowest in well-differentiated PC (25.8%). Normal prostatic epithelia and hyperplasia were characterized by low EMBP expression, although somewhat higher than well-differentiated PC. A moderate expression (45%) was observed in the seminal vesicles. According to these results, EMBP was expressed mainly in the diseased peripheral zone (PZ), where PIN and prostatic cancer have their highest prevalence.
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| 10. |
- Dubois, Louise, et al.
(author)
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Malignant Cell-Derived Extracellular Vesicles Express Different Chromogranin Epitopes Compared to Prostasomes
- 2015
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In: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 75:10, s. 1063-1073
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Journal article (peer-reviewed)abstract
- BACKGROUND. Prostasomes are nanosized extracellular vesicles exocytosed by prostate epithelial cells. They have been assigned many roles propitious to sperm in favor of fertilization. Prostatic cancer cells can also produce and secrete extracellular vesicles. METHODS. We assessed using ELISA, the surface expression of chromogranin proproteins on prostasomes and malignant extracellular vesicles of four different prostate cancer cell-lines, two hormone sensitive and two hormone refractory. We used a panel of chromogranin A and chromogranin B antibodies against peptides in-between hypothetical cleavage sites along the proproteins. RESULTS. A diverging pattern of chromogranin peptides was apparent when comparing prostasomes and malignant extracellular vesicles indicating a phenotypical change. We also compared western blot patterns (prostasomes and malignant extracellular vesicles) for selected antibodies that displayed high absorbances in the ELISA. Western blot analyses revealed various cleavage patterns of those proproteins that were analyzed in prostasomes and extracellular vesicles. CONCLUSION. Chromogranins are constituents of not only prostasomes but also of malignant prostate cell-derived extracellular vesicles with different amino acid sequences exposed at the membrane surface giving rise to a mosaic pattern. These findings may be of relevance for designing new assays for detection or even possible treatment of prostate cancers.
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