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1.
Oncogene ; 20(22): 2836-43, 2001 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-11420695

RESUMO

The role of Bcl-2 in TRAIL-induced apoptosis has been investigated in lymphoid cells. Here we show that the human prostatic carcinoma cell line PC3 was sensitive to TRAIL treatment whereas PC3 overexpressing of Bcl-2 was resistant. TRAIL receptors ligation in PC3 activated caspases -2, -3, -7, -8, and -9, induced Bid processing, dissipation of mitochondrial transmembrane potential (Delta Psi(m)), and cytochrome c release. We have detected caspases -8 and -3 only in the cytosolic fraction of cells, but caspases -2, -7, and -9 were found both in cytosolic and mitochondrial fractions. Bcl-2 overexpression did not affect caspase-8 activation although it did change the processing pattern of caspase-3. At the same time, Bcl-2 overexpression inhibited the activation of mitochondrial localized caspases -2, -7, and -9. Bcl-2 also abrogated TRAIL-induced cytochrome c release and dissipation of Delta Psi(m). These findings suggest that TRAIL-induced apoptosis in the epithelial cell line PC3 depends both on mitochondrial integrity and caspase activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Glicoproteínas de Membrana/farmacologia , Neoplasias da Próstata/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Grupo dos Citocromos c/metabolismo , Indução Enzimática , Proteína de Domínio de Morte Associada a Fas , Humanos , Masculino , Mitocôndrias/metabolismo , Neoplasias da Próstata/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas/efeitos dos fármacos
2.
Lab Invest ; 80(5): 671-6, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830777

RESUMO

Treatment of cells with synthetic C2-ceramide has been reported to induce apoptosis in several cell systems, and endogenously formed ceramide has been proposed to act as a second messenger, activating signaling pathways which contribute to the execution of apoptotic cell death after Fas ligation or tumor necrosis factor receptor-1 ligation. In this study, we examined the effect of exogenously administered C2-ceramide on the human prostatic carcinoma cell lines PC3 (Fas-sensitive) and DU145 (Fas-resistant). In both cell lines, C2-ceramide induced cell death in a dose-dependent manner, whereas a structural analog, C2-dihydroceramide, did not. The pan-caspase inhibitor zVAD-fmk did not prevent C2-ceramide-induced cell death but did prevent C2-ceramide-induced DNA fragmentation, indicating that apoptotic and non-apoptotic mechanisms are involved in C2-ceramide-induced death. Interestingly, cycloheximide prevented C2-ceramide-induced DNA fragmentation, indicating that ceramide-induced apoptosis in PC3 and DU145 requires new protein synthesis. In addition, because cycloheximide converts Fas-resistant DU145 to Fas-sensitive as assessed by DNA fragmentation, ceramide does not seem to play a major role in the Fas-mediated pathway in this cell line. We also determined the levels of endogenous sphingomyelin after Fas ligation in PC3. No decrease of sphingomyelin levels could be detected after Fas activation. We conclude that sphingomyelinase-generated ceramide does not play a role in Fas-mediated apoptosis in PC3, and that there are fundamental differences in the mechanisms of cell death induced by C2-ceramide and Fas ligation.


Assuntos
Apoptose/efeitos dos fármacos , Ceramidas/farmacologia , Neoplasias da Próstata/patologia , Receptor fas/fisiologia , Clorometilcetonas de Aminoácidos/farmacologia , Inibidores de Caspase , Caspases/fisiologia , Cicloeximida/farmacologia , Humanos , Masculino , Esfingomielinas/análise , Células Tumorais Cultivadas
3.
Oncogene ; 19(15): 1959-68, 2000 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-10773886

RESUMO

The human prostatic carcinoma cell line LNCaP is sensitive to TNF-alpha treatment and expresses wild-type p53. To analyse the possible role of p53 in TNF-alpha-mediated apoptosis, we generated a derivative of LNCaP, LN-56, expressing a dominant-negative element of p53, GSE56. P53 inactivation in LN-56 was associated with an increased resistance to apoptosis induced by TNF-alpha. Surface expression of TNF-alpha receptors was unchanged in LN-56 compared to LNCaP. TNF-alpha treatment resulted in accumulation of p53 in LNCaP and upregulation of p21/WAF1. Activation of caspase-7 and PARP proteolysis were delayed in LN-56 under TNF-alpha treatment. TNF-alpha-induced apoptosis in LNCaP cells was accompanied by caspase-dependent proteolysis of p21/WAF1 and Rb, which was significantly attenuated in LN-56. Cytochrome c release was induced by TNF-alpha treatment in both cell lines, but caspase-9 was not activated. LNCaP and LN-56 were injected s.c. in nude mice and tumors were identified in all LN-56, but not LNCaP, bearing mice indicating that p53 plays an important role in growth control of prostatic neoplasms. Interestingly, accumulation of p53 in TNF-alpha-treated LNCaP cells was decreased in the presence of the caspase inhibitor Z-VAD-FMK, suggesting a new role of activated caspases in acceleration of p53 response. In summary, these results indicate that p53 is involved in TNF-alpha-mediated apoptosis in LNCaP.


Assuntos
Apoptose , Neoplasias da Próstata/patologia , Fator de Necrose Tumoral alfa/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Caspases/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Grupo dos Citocromos c/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases , Neoplasias da Próstata/metabolismo , Proteínas/metabolismo , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/antagonistas & inibidores , Regulação para Cima
4.
Cancer Res ; 60(8): 2163-8, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10786680

RESUMO

We have shown previously that the pathways leading to Fas-mediated apoptosis in prostatic carcinoma cell lines are intact, because apoptosis can be triggered either by Fas ligation alone in the Fas-sensitive cell lines PC3 and ALVA31 or by rendering the Fas-resistant cell lines DU145 and JCA1 Fas-sensitive by combined treatment with anti-Fas monoclonal antibody and cycloheximide (O. W. Rokhlin et al., Cancer Res., 57: 1758-1768, 1997). In this study, we demonstrate that two of the early events after Fas ligation are the release of cytochrome c from the mitochondria and activation of caspase-9. We also found that Bid is processed after Fas ligation and thus might activate the mitochondria-dependent apoptotic cascade. In a cell-free system, cytochrome c induced caspase-3-like activity in cytoplasmic extracts from all four cell lines studied, although differences in the level of enzymatic activity were observed. Western blot analysis revealed that caspase-7 is activated by cytochrome c at the same level in all extracts, whereas expression and activation of caspase-3 varied considerably. Cytochrome c-activated extracts displayed different abilities in the induction of apoptotic features in isolated nuclei such as morphological changes and DNA fragmentation. However, differences in nuclear apoptotic activity induced by cytochrome c did not correlate with the level of caspase-3 like activity in the different extracts. These results suggest that the mitochondrial pathway is involved in Fas-mediated apoptosis in prostatic carcinoma cell lines and that, in addition to caspase-7 and caspase-3, there are other factors that confer nuclear apoptotic activity.


Assuntos
Apoptose , Grupo dos Citocromos c/metabolismo , Mitocôndrias/patologia , Neoplasias da Próstata/patologia , Receptor fas/metabolismo , Anticorpos Monoclonais/imunologia , Apoptose/efeitos dos fármacos , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cicloeximida/farmacologia , Citoplasma/efeitos dos fármacos , Citoplasma/enzimologia , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Masculino , Mitocôndrias/metabolismo , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Células Tumorais Cultivadas , Receptor fas/imunologia
5.
Cancer Lett ; 131(2): 129-36, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9851244

RESUMO

We created mAb that reacted solely with prostate epithelial cells. The strategy involved immunizing mice with a mixture of six different prostatic carcinoma cell lines and selecting by flow cytometry only those antibodies that bind whole cells. The primary screening was performed using a mixture of all six prostate cell lines used in immunization together with six non-prostate cell lines in the same tube. Antibodies that gave a bimodal pattern of surface staining were selected for further evaluation. The most attractive clone, designated 5E10, produced IgG1 mAb that recognized four of the six prostatic cell lines and did not react with non-prostate tumor cell lines, peripheral blood and bone marrow mononuclear cells and endothelial and bone marrow stromal cells. 5E10 mAb reacted with both benign and malignant prostate in eight of eight histological samples and no reactivity was noted with non-prostate normal tissues. The 5E10 antigen is a transmembrane glycoprotein with a molecular weight of 110 kDa and the epitope recognized by 5E10 is extracellular. Ongoing studies are exploring the nature of this antigen in more depth.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antineoplásicos/isolamento & purificação , Neoplasias da Próstata/imunologia , Animais , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Citometria de Fluxo , Humanos , Hibridomas , Imunoglobulina G/isolamento & purificação , Imuno-Histoquímica , Masculino , Camundongos , Peso Molecular , Células Tumorais Cultivadas
6.
Cancer Res ; 58(24): 5870-5, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9865748

RESUMO

We previously demonstrated that treatment with cycloheximide (CHX) converted the phenotype of Fas-resistant human prostatic carcinoma cell lines to Fas-sensitive and that resistance to Fas-mediated apoptosis was due to a dominant-negative protein(s). In this study, we investigated the sequential activation of caspase family members, to gain insight into the likely site of action of the suppressor protein(s). We did not find Tyr-Val-Ala-Aspase activity in any of the cell lines examined. Time-dependent Asp-Glu-Val-Aspase activity was detected during Fas-mediated apoptosis in Fas-sensitive cell lines PC3 and ALVA31. Asp-Glu-Val-Aspase activity in Fas-resistant cell lines DU145 and JCA1, was detected only under combined treatment with CHX and anti-Fas agonistic mAb. In experiments with caspase inhibitors we show that Fas-mediated apoptosis in PC3 is mainly executed by the caspase-3 subfamily, but another member(s) of the caspase family may be involved in Fas-mediated apoptosis in ALVA31, DU145, and JCA1. Western blot analysis revealed that Fas-ligation activated caspase-7, but not caspase-3. The activated form of caspase-8 was detected in DU145 only after 4 h of simultaneous treatment with CHX and anti-Fas mAb, whereas in PC3 caspase-8 was found to be activated after 1 h of Fas-ligation. We have also found that treatment with staurosporin did not activate caspase-8, whereas staurosporin induced apoptosis at the same levels in both Fas-resistant and Fas-sensitive cell lines. These results suggest that an inhibitory protein(s), which suppresses apoptosis in Fas-resistant cell lines, presumably acts at the apex of apoptotic cascade by preventing the activation of caspase-8.


Assuntos
Apoptose , Caspases/metabolismo , Neoplasias da Próstata/patologia , Receptor fas/farmacologia , Western Blotting , Caspase 7 , Caspase 8 , Caspase 9 , Ativação Enzimática , Humanos , Masculino , Neoplasias da Próstata/enzimologia , Proteína do Retinoblastoma/metabolismo , Estaurosporina/farmacologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia
7.
Oncogene ; 17(9): 1089-96, 1998 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-9764819

RESUMO

p53 tumor suppressor gene controls cell response to a variety of stresses inducing growth arrest or apoptosis in damaged cells. It largely determines the sensitivity of tumor and normal cells to radiation and chemotherapy, and, therefore, defines both the efficacy and limitations of anti-cancer treatment. To determine molecular mechanisms of p53-dependent stress response in normal tissues we identified and compared the spectra of radiation-responsive genes in cells of different origin and p53 status using a cDNA array hybridization technique. The majority of genes identified were p53-dependent and cell type specific. Several of the new p53 responders encode known secreted growth inhibitory factors. This suggests that p53, in addition to its intrinsic antiproliferation activity, can cause 'bystander effect' by inducing export of growth suppressive stimuli from damaged cells to neighboring cells. Consistently, a p53-dependent accumulation of factors, which causes growth inhibitory effects in a variety of cell lines, was found after gamma irradiation in the media from established and primary cell cultures and in the urine of irradiated mice. Moreover, p53-dependent factors released by normal human fibroblasts potentiated the cytotoxic effect of a chemotherapeutic drug on co-cultivated tumor cells. This suggests a previously unknown role for normal cells in chemo- and radiation therapy of cancer.


Assuntos
Inibidores do Crescimento/metabolismo , Estresse Fisiológico/fisiopatologia , Células 3T3/citologia , Células 3T3/metabolismo , Células 3T3/efeitos da radiação , Animais , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Divisão Celular/efeitos da radiação , Linhagem Celular , Raios gama , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Expressão Gênica/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Genes/genética , Genes/efeitos da radiação , Genes Supressores de Tumor/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/efeitos da radiação , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/fisiologia
8.
Cancer Res ; 57(18): 3941-3, 1997 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9307276

RESUMO

We have recently found (O. W. Rokhlin et al., Cancer Res., 57: 1758-1768, 1997) that, although Fas ligation induced apoptosis in two of six human prostatic carcinoma cell lines investigated, the apoptotic machinery involved in Fas-mediated killing is already in place in Fas-resistant cell lines. Here, we investigated Fas- and tumor necrosis factor-alpha (TNF-alpha)-mediated apoptosis in cell hybrids between resistant (DU145 and JCA1) and sensitive (ALVA31 and PC3) cell lines. All three types of hybrid cells investigated, F1(DU145 x PC3), F1(JCA1 x PC3), and F1(JCA1 x ALVA31), were found to be resistant to Fas- and TNF-alpha-mediated apoptosis at the same level as the corresponding parental resistant cell lines. These results indicate that resistance to Fas- and TNF-alpha-mediated apoptosis dominates over sensitivity in cell hybrids and suggest that resistance may be regulated by an apoptosis suppressor factor or factors acting in resistant but not in sensitive cells.


Assuntos
Apoptose , Carcinoma/patologia , Neoplasias da Próstata/patologia , Fator de Necrose Tumoral alfa/fisiologia , Receptor fas/fisiologia , Divisão Celular , Fragmentação do DNA , Genes Dominantes , Humanos , Células Híbridas , Imunofenotipagem , Masculino
9.
Cancer Res ; 57(9): 1758-68, 1997 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9135020

RESUMO

Of six prostatic carcinoma cell lines examined (ALVA31, DU145, JCA1, LNCaP, ND1, and PC3) by flow cytometric analysis, all were found to be positive for Fas antigen. Furthermore, of the prostate tissue specimens studied (six cases), all revealed Fas expression in benign and malignant epithelial cells. The agonistic anti-Fas monoclonal antibody (IPO-4) induced apoptosis in only two of six cell lines investigated, PC3 and ALVA31. PCR analysis indicated that all cell lines expressed normal transmembrane and death domains of Fas antigen. Using Western blot analysis, we found abundant expression of p53 in the cytoplasm of two Fas-resistant cell lines, DU145 and ND1, and did not find p53 in two Fas-sensitive cell lines, PC3 and ALVA31. Western blot and PCR analysis did not show consistent differences between cell lines examined in the expression of Bcl-2, Bcl-X(L), Bcl-X(S), and Bak. In contrast, Bax protein was not detected in two Fas-resistant cell lines, DU145 and ND1. We also showed that three Fas-resistant cell lines, DU145, ND1, and JCA1, expressed CD40, whereas the two Fas-sensitive cell lines, PC3 and ALVA31, were CD40 negative. Fas-sensitive cell lines were transfected with the cDNA encoding CD40, and the CD40-positive transfectant became more resistant to growth inhibition mediated by treatment with TNF-alpha and anti-Fas monoclonal antibody. Treatment with cycloheximide converted the phenotype of resistant cell lines from Fas resistant to Fas sensitive. Moreover, anti-Fas treatment of both resistant and sensitive cell lines induced rapid tyrosine phosphorylation or dephosphorylation of multiple proteins. These results suggest that the apoptotic machinery involved in DNA fragmentation is already in place in Fas-resistant cell lines, and thus, Fas-mediated apoptosis could be a target for therapeutic intervention.


Assuntos
Apoptose , Neoplasias da Próstata/patologia , Receptor fas/fisiologia , Reações Antígeno-Anticorpo , Antígenos CD40/genética , Antígenos CD40/metabolismo , Divisão Celular , Cicloeximida/farmacologia , Fragmentação do DNA , Citometria de Fluxo , Humanos , Masculino , Fosfotirosina/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2 , Proteína bcl-X
10.
Am J Clin Pathol ; 107(1): 56-63, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8980368

RESUMO

Cell adhesion molecules (CAMs) are important in cell-cell interaction and interactions between cells and components of the extracellular matrix. CAMs have been associated with invasion and metastasis in a wide variety of human malignancies, including tumors of the genitourinary tract. Cadherins are transmembrane glycoproteins that bind cells by homophilic, homotypic interactions. Loss of expression of E-cadherin has been associated with dedifferentiation, invasion, and metastasis in prostate cancer and transitional cell neoplasia of the urinary bladder. CD44, a family of transmembrane glycoproteins principally involved in cell-extracellular matrix interactions, also has been associated with invasion and metastasis in urologic malignancies. Through alternative splicing, a variety of CD44 isoforms can be expressed that can undergo extensive posttranslational modification. CD44 variants have been associated with metastasis in a variety of human malignancies, particularly in the gastrointestinal system. Although loss of expression of CD44 standard form has been associated with aggressive prostate gland and bladder cancers, no specific isoform has been associated with metastasis of these neoplasms. Integrins are transmembrane glycoproteins with wide cellular distribution that bind a variety of extracellular matrix components. Integrins have been studied extensively in prostate cancer in which altered integrin expression has been associated with malignant prostatic epithelium. Additional adhesion molecules that have been studied to a variable degree in urologic malignancies include selectins and the immunoglobulin super-family. CAMs are fundamental to diverse biologic processes and appear capable of regulating intracellular signaling events that appear to have significant importance in human malignancy, including cancers of the urogenital tract.


Assuntos
Moléculas de Adesão Celular/fisiologia , Neoplasias Urogenitais/fisiopatologia , Feminino , Humanos , Masculino , Neoplasias Urogenitais/metabolismo
11.
Cancer Lett ; 107(1): 29-35, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8913263

RESUMO

We have identified that human prostatic cancer cell lines DU145, PC3, ND1, ALVA31 and JCA1 released soluble CD44 molecules and DU145, PC3 and ND1 released soluble CD54. Both soluble and surface CD44 were not found in LNCaP, and both forms of CD54 were not expressed in LNCaP and JCA1. CD54 was found to be highly expressed on cell surface in ALVA31, but these cells did not release soluble CD54. Expression of both cell surface and soluble forms were examined after treatment of cells with IFN-gamma, TGF-beta 1, or culturing in serum-free media. The concentration of soluble CD54 in supernatants changed to small extent after treatment with TGF-beta 1 and increased after treatment with IFN-gamma or in serum-free media. Cell surface expression of CD54 however, changed only minimally after treatment. The levels of cell surface and soluble CD44 also changed minimally after treatment with IFN-gamma and TGF-beta 1 but decreased in serum-free media and this was accompanied by marked elevation of soluble CD44 in supernatants. These data indicate that soluble CD44 might be released from cell surface by shedding whereas alternative splicing is the most likely mechanism of soluble CD54 release.


Assuntos
Moléculas de Adesão Celular/metabolismo , Receptores de Hialuronatos/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interferon gama/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Humanos , Masculino , Células Tumorais Cultivadas
12.
Prostate ; 28(3): 153-61, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8628718

RESUMO

We have examined the expression of the transmembrane glycoproteins CD44 in four human prostate tumor cell lines. Expression was examined at the protein level by flow cytometric analysis and Western blot, and at the mRNA level by reverse transcription-polymerase chain reaction (RT-PCR). All four cell lines (DU145, LNCaP, PC3, and ND1) expressed the standard CD44 isoform (CD44s) at the mRNA level and all cell lines except LNCaP expressed CD44s at the protein level. All four cell lines contained one or more isoforms containing the v6 region (exon 10) at the mRNA level, which has been associated with metastatic potential. However, a subpopulation of LNCaP and ND1 cells showed protein expression of v6. In addition, soluble CD44 isoforms were identified in cultured supernatants from all cell lines except LNCaP. These results show that CD44 isoforms are expressed on human prostate tumor cell lines, including the expression of variant isoforms containing the v6 region, and provide a rationale for the further study of this cellular adhesion molecule in prostate cancer. In addition, preliminary results indicate altered expression of CD44 in human prostatic adenocarcinomas examined immunohistochemically.


Assuntos
Receptores de Hialuronatos/análise , Neoplasias da Próstata/química , Animais , Sequência de Bases , Western Blotting , Citometria de Fluxo , Humanos , Receptores de Hialuronatos/genética , Imuno-Histoquímica , Masculino , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
13.
Anticancer Res ; 16(2): 557-63, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8687098

RESUMO

Using specific ELISA kits, we investigated the secretion of cytokines in five human prostate carcinoma cell lines: ALVA 31, DU145, LNCaP, ND1 and PC3. Three of the five cell lines investigated secreted granulocyte-macrophage colony-stimulating factor (GM-CSF); GM-CSF was not identified in ALVA31 or LNCaP. In addition, we have shown that conditioned media of DU145, ND1 and PC3 stimulated proliferation of the GM-CSF-dependent cell line MO7e indicating that these cells secrete biologically active GM-CSF. By flow cytometric analysis we determined that all five cell lines expressed the alpha-subunit of the GM-CSF receptor on the cell surface but only ALVA31 expressed both the alpha- and beta-subunits of the GM-CSF receptor. Varying concentrations of GM-CSF did not stimulate the proliferation rate of any of the prostate carcinoma cell lines. Thus, there does not appear to be autocrine loop of GM-CSF-induced proliferation. However, the expression of E-cadherin and endoglin (CD105) was modulated under GM-CSF treatment in ALVA31. In addition, GM-CSF decreased the level of soluble CD44 in ND1. These results suggest that the GM-CSF receptor alpha-subunit may play a role in metabolic activity of prostate cancer.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Moléculas de Adesão Celular/metabolismo , Divisão Celular , Citocinas/metabolismo , Humanos , Masculino , Proteínas de Membrana/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
14.
Cancer Lett ; 98(1): 103-10, 1995 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-8529197

RESUMO

We investigated the effect of protein kinase and phosphatase inhibitors on the growth of six human prostatic cancer cell lines: DU145, PC3, ND1, LNCaP, ALVA31 and JCA1. We studied okadaic acid and sodium orthovanadate as serine/threonine and tyrosine protein phosphatase inhibitors, respectively, and staurosporin and genistein as a serine/threonine and tyrosine protein kinase inhibitors, respectively. All inhibitors examined exhibited a dose-dependent growth inhibitory effect on prostatic cancer cell lines. Our data indicate that prostatic cancer cell lines express unique biochemical properties since the degree of growth inhibition varied greatly and was dependent on the specific cell line and inhibitor studied. In addition, we found that surface expression of endoglin (CD105) changed by treatment with all inhibitors in most of the cell lines. These data also indicate that endoglin appears to be involved both in protein phosphatase and kinase mediated phosphoprotein turnover.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/enzimologia , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antígenos CD , Antígenos de Neoplasias/biossíntese , Moléculas de Adesão Celular/biossíntese , Divisão Celular/efeitos dos fármacos , Endoglina , Inibidores Enzimáticos/farmacologia , Éteres Cíclicos/farmacologia , Éteres Cíclicos/uso terapêutico , Genisteína , Humanos , Receptores de Hialuronatos/biossíntese , Molécula 1 de Adesão Intercelular/biossíntese , Isoflavonas/farmacologia , Isoflavonas/uso terapêutico , Masculino , Ácido Okadáico , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores de Superfície Celular , Estaurosporina , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologia , Vanadatos/farmacologia , Vanadatos/uso terapêutico , Molécula 1 de Adesão de Célula Vascular/biossíntese
15.
J Immunol ; 154(9): 4456-65, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7722302

RESUMO

Endoglin, a glycoprotein that is expressed by human endothelial cells, binds TGF-beta 1 and -beta 3 with high affinity. It was originally identified with the 44G4 mAb that was produced against a human pre-B cell line. We now report that another anti-pre-B cell mAb, 29-G8, reacts with pro-B and pre-B leukemic cells, but not with mature B and T cells, and recognizes a different epitope of endoglin. The 29-G8 mAb bound specifically to recombinant endoglin and immunoprecipitated a phosphorylated homodimeric glycoprotein with subunits of M(r) 95,000 from the 697 pre-B cell line. This new Ab removed all of the molecules identified by the prototypic 44G4 anti-endoglin Ab, but the reverse was not true. A subpopulation of 29-G8+ endoglin molecules on this pre-B cell line was unreactive with the 44G4 mAb, thus suggesting that these anti-endoglin Abs see different epitopes that may discriminate different species of endoglin molecules. Flow cytometric analysis with the 29-G8 mAb revealed two endoglin-positive subpopulations in fetal bone marrow: early B-lineage precursor cells (CD19+ and CD34+), and proerythroblasts (CD71+ and glycophorin A+). In adult bone marrow, only the proerythroblast subpopulation was observed. Stromal cells derived from fetal bone marrow also reacted strongly with the 29-G8 and 44G4 Abs, and these cells responded with enhanced proliferation after stimulation with either TGF-beta 1 or the anti-endoglin Abs. Thus, endoglin, a specialized component of the TGF-beta receptor system, may play a physiologic role in the stromal-hemopoietic cell interactions occurring during development.


Assuntos
Medula Óssea/embriologia , Células-Tronco Hematopoéticas/química , Glicoproteínas de Membrana/análise , Molécula 1 de Adesão de Célula Vascular , Adulto , Anticorpos Monoclonais/imunologia , Antígenos CD , Linfócitos B/química , Células da Medula Óssea , Divisão Celular/fisiologia , Linhagem Celular , Endoglina , Feto/química , Citometria de Fluxo , Humanos , Hibridomas , Técnicas Imunoenzimáticas , Receptores de Superfície Celular , Células Estromais/química
16.
Prostate ; 26(4): 205-12, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7536326

RESUMO

By flow cytometric analysis we have examined the expression of cellular adhesion molecules (CAMs) on the surface of four different human prostate tumor cell lines: DU 145, from a brain metastasis; PC 3, from a bone metastasis; LNCaP.FGC, from a lymph node metastasis; and a primary tumor cell line, ND 1. The corresponding ligands for the expressed CAMs were, by and large, extracellular matrix proteins. We detected high-level expression of ICAM-1 on three of the four prostate cell lines, whereas LNCaP cells were negative. We observed unstable, heterogeneous expression of E-cadherin in the cell lines DU 145, PC 3, and ND 1. Flow cytometric cell sorting enabled us to divide PC 3 cells into negative and bright positive subpopulations but, after several cell divisions in culture, sorted cells returned to the original heterogeneous phenotype. The laminin-specific alpha 6 beta 4 integrin was not expressed by LNCaP, and was expressed at a low level and heterogeneously on DU 145 and PC 3 cell lines. In contrast, ND 1 cells, derived from a primary tumor, showed homogeneous and high-level expression of the alpha 6 beta 4 integrin. All of the prostate cell lines expressed the RGD-dependent binding of alpha 3 beta 1 and alpha 5 beta 1 integrins and did not reveal non-RGD-dependent alpha 4 beta 1 integrin expression. This finding provides a stimulus to investigate the inhibition capacity of RGD-containing peptides on the metastatic behavior of prostate tumor cells.


Assuntos
Moléculas de Adesão Celular/análise , Neoplasias da Próstata/química , Caderinas/análise , Antígenos HLA-DR/análise , Humanos , Integrinas/análise , Molécula 1 de Adesão Intercelular/análise , Masculino , Células Tumorais Cultivadas , Molécula 1 de Adesão de Célula Vascular
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