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1.
Tumour Biol ; 25(1-2): 69-90, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15192315

RESUMO

Thirteen monoclonal antibodies directed against squamous cell carcinoma antigens (SCCA1 and SCCA2) were obtained from five international collaborating laboratories participating in the ISOBM TD-10 Workshop. Native and recombinant forms of SCCA were used in a wide variety of approaches to determine the reactivity and specificity of these antibodies. Based on reactivity, the antibodies could be divided into three groups: the SCCA1-reactive group containing those that reacted only with recombinant SCCA1 (rSCCA1) and native SCCA1 (nSCCA1) antigens, the SCCA2-reactive group containing those that reacted only with recombinant SCCA2 (rSCCA2), and the pan-reactive group containing those antibodies that reacted with rSCCA1, nSCCA1, and rSCCA2. Binding to radioiodinated rSCCA1 showed that all reactive antibodies were of a high affinity (K(d) <2 x 10(-9) mol/l). Binding to labelled rSCCA2 demonstrated that five antibodies were of a high affinity (K(d) <2 x 10(-9) mol/l). Antibody reactivity on Western blots was tested with nonreduced and reduced native and recombinant SCCA1 and SCCA2. In general, these findings showed that reduction had little effect on binding to SCCA1, but often a strong effect on the binding to SCCA2. Binding of antibodies to rSCCA1 and rSCCA2 in complexes with cathepsin L and G, respectively, was used to assist in the localization of epitope regions in enzyme-complexed SCCA. Cross-inhibition experiments showed that SCCA1-reactive antibodies represent two different epitope groups, and this is supported by their ability to make SCCA1-specific assays by combining antibodies from the two epitope groups. The SCCA2-reactive group represents two related antibodies and one unique as seen in cross-inhibition, but they do not form successful assay combinations. Classification of the pan-reactive antibodies is more difficult, as some epitope groups differ when results from rSCCA1 are compared with rSCCA2 as the target. However, two antibodies are outstanding, SCC107 and SCC113, as they are high-affinity antibodies which react equally well with free and protease complexes of SCCA1 and SCCA2. The precise location of epitopes was further studied using sequential overlapping peptides and homology modelling. The findings from this workshop strongly indicate that the recombinant antigens (rSCCA1 and rSCCA2) are very similar in epitope structure to the native counterparts in saliva, and squamous epithelium from normal and cancer tissues. Therefore, it is reasonable to conclude that the specificities found are reliable and have application for antibody measurement of all forms of squamous cell carcinoma in serum except SCCA2 in complex with its protease.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/imunologia , Carcinoma de Células Escamosas/imunologia , Serpinas/imunologia , Anticorpos Monoclonais/análise , Formação de Anticorpos , Western Blotting , Humanos , Sensibilidade e Especificidade
2.
Electrophoresis ; 22(16): 3522-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11669536

RESUMO

The aim of this study was to investigate the heat stability of squamous cell carcinoma (SCC) antigen, a tumor-associated serine proteinase inhibitor (serpin), in tumor tissue extract by electrophoretic methods. After heat treatment at 70 degrees C for 2 h, the tumor tissue extract showed a single main protein band of 45 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) which reacted with a monoclonal antibody specific for SCC antigen. The heat-stable SCC antigen was separated by two-dimensional electrophoresis (2-DE) into four spots with pI 6.4-5.9 and Mr 44500-45 000 of SCC antigen-1. Furthermore, the SCC antigen-1 still showed its inhibitory activity against a cysteine proteinase, papain, by gelatin zymography. These results suggest that heat treatment of protein sample at 70 degrees C for 2 h may be a useful method for a partial purification of SCC antigen-1 which can inhibit lysosomal cysteine proteinases such as cathepsin L, S, and K.


Assuntos
Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/química , Serpinas/análise , Carcinoma de Células Escamosas/patologia , Eletroforese em Gel Bidimensional/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Calefação , Humanos , Dodecilsulfato de Sódio , Extratos de Tecidos/química
3.
Biochim Biophys Acta ; 1519(1-2): 122-6, 2001 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-11406281

RESUMO

Squamous cell carcinoma antigen (SCCA) is a member of the ovalbumin serine protease inhibitor family, and the serum level of SCCA is a tumor marker of squamous cell carcinoma. Reverse transcription (RT)-PCR of the squamous cell carcinoma cell line showed the existence of a 156 base shorter transcript compared with that of SCCA1 cDNA. By inverse PCR, we cloned the full length cDNA of this SCCA (SCCA1b). Sequence analysis of the complete 1541 bp SCCA1b cDNA showed that it coded for 338 amino acids and had no typical signal sequence in the NH(2) terminus. The cDNA was expressed in Escherichia coli and the product was detected using Western blotting with antibodies against SCCA. Furthermore, RT-PCR of the full coding region of SCCA2 cDNA from cancer tissue showed the existence of a 63 base short transcript (SCCA2b). A comparison of SCCA1b and SCCA2b cDNA with the SCCA1 and SCCA2 genes showed that these messages were derived from each gene by an alternative splicing mechanism.


Assuntos
Processamento Alternativo , Antígenos de Neoplasias/genética , Sequência de Aminoácidos , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/química , Carcinoma de Células Escamosas/imunologia , Clonagem Molecular , DNA Complementar/biossíntese , DNA Complementar/química , Escherichia coli/metabolismo , Éxons , Humanos , Íntrons , Dados de Sequência Molecular , Isoformas de Proteínas/genética , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Serpinas/genética , Células Tumorais Cultivadas
4.
Br J Cancer ; 84(6): 851-8, 2001 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-11259103

RESUMO

Previous study has demonstrated that squamous cell carcinoma antigen (SCCA) 1 attenuates apoptosis induced by TNF alpha, NK cell or anticancer drug. In this study, we have examined the effect of SCCA2, which is highly homologous to SCCA1, but has different target specificity, against radiation-induced apoptosis, together with that of SCCA1. We demonstrated that cell death induced by radiation treatment was remarkably suppressed not only in SCCA1 cDNA-transfected cells, but also in SCCA2 cDNA-transfected cells. In these transfectants, caspase 3 activity and the expression of activated caspase 9 after radiation treatment were suppressed. Furthermore, the expression level of phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) was suppressed compared to that of the control cells. The expression level of upstream stimulator of p38 MAPK, phosphorylated MKK3/MKK6, was also suppressed in the radiation-treated cells. Thus, both SCCA1 and SCCA2 may contribute to survival of the squamous cells from radiation-induced apoptosis by regulating p38 MAPK pathway.


Assuntos
Antígenos de Neoplasias/imunologia , Carcinoma de Células Escamosas/imunologia , Morte Celular/imunologia , Morte Celular/efeitos da radiação , Serpinas , Sequência de Bases , Carcinoma de Células Escamosas/enzimologia , Caspases/metabolismo , Primers do DNA , Ativação Enzimática , Humanos , Proteínas Quinases/metabolismo , Células Tumorais Cultivadas
5.
Cancer Res ; 61(5): 1776-80, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11280721

RESUMO

Squamous cell carcinoma (SCC) antigen (SCCA), a member of the ovalbumin serine proteinase inhibitor family, serves as a circulating marker of squamous cell carcinoma (SC). One of the SCCAs, SCCA1, has been suggested to play a role in the attenuation of apoptosis in vitro and in the augmentation of tumor growth in vivo. In the present study, the infection of a SCC cell line (SKG IIIa) with recombinant retrovirus that expressed the antisense SCCA mRNA suppressed expression of SCCA in vitro. Local administration of this retrovirus into tumors by inoculation in nude mice suppressed tumor growth. Treatment of tumor tissue in vivo is also associated with increased numbers of apoptotic tumor cells and large mononuclear cells in the tumor. To test the possible role of SCCA in the infiltration of large mononuclear cells, we analyzed the effect of SCCA1 on migration of natural killer (NK) cells induced by monocyte-chemoattractant protein-1 in vitro. SCCA1 suppressed migration of NK cells completely, and this inhibitory effect was lost by mutation of the reactive site loop of SCCA1. These results suggest that antisense SCCA may suppress the growth of SCC in vivo not only by the augmentation of intracellular apoptosis but also by the increased infiltration of NK cells into the tumor.


Assuntos
Antígenos de Neoplasias/biossíntese , Carcinoma de Células Escamosas/patologia , Células Matadoras Naturais/patologia , Oligonucleotídeos Antissenso/farmacologia , Serpinas/biossíntese , Células 3T3 , Animais , Antígenos de Neoplasias/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Divisão Celular , Movimento Celular/efeitos dos fármacos , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oligonucleotídeos Antissenso/genética , Serpinas/genética , Transdução Genética
6.
Tumour Biol ; 22(3): 162-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11275794

RESUMO

The aim of the present study was to evaluate the clinical significance of the serum anti-p53 antibody in patients with uterine and ovarian cancer. Some of the ovarian patients were also evaluated for overexpression of p53 by immunohistochemistry and for cytogenetic alterations by comparative genomic hybridization (CGH). Serum anti-p53 antibodies were determined by an enzyme immunoassay kit. The antibody was detected in 8/30 (27%) of ovarian cancers, in 12/86 (14%) cancers of the uterine cervix, in 5/41 (12%) cancers of the uterine body, and 0/9 (0%) healthy women. The overall survival rate in patients with ovarian cancer was significantly worse in patients with anti-p53 antibody positivity than that in patients with anti-p53-antibody-negative cancers using the log rank test (p = 0.017). There was a significant correlation between the presence of anti-p53 antibody and tissue overexpression of p53 in ovarian cancers. CGH analysis showed that the aberrations in DNA sequence copy number in ovarian cancers were significantly increased in anti-p53-antibody-positive cases compared to antip53-antibody-negative cases including increased copy number on 20q and reduced copy number on 5q and 13q. Although the exact relationship between the presence of serum anti-p53 antibody (specific humoral response) and cytogenetic alterations is still unknown, these findings suggest that the measurement of serum anti-p53 antibody may be useful for the assessment of genetic instability and tumor biological aggressiveness.


Assuntos
Genes p53 , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Proteína Supressora de Tumor p53/imunologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/imunologia , Idoso , Anticorpos/sangue , Aberrações Cromossômicas , Feminino , Amplificação de Genes , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/mortalidade , Neoplasias Uterinas/mortalidade
7.
Electrophoresis ; 22(1): 161-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11197167

RESUMO

Two homologous serine proteinase inhibitors (serpins), squamous cell carcinoma (SCC) antigen-1 and -2 were separated by nondenaturing two-dimensional electrophoresis combined with immunostaining to acquire further information on these proteins under physiological conditions. Polymers of SCC antigen-2 were detected in cytosolic extracts prepared from tumor tissues. The polymer formation of SCC antigen-2 was apparently decreased and the SCC antigen-2-synthetic peptide binary complexes were newly formed by the addition of synthetic peptide with sequences corresponding to residues from P14 to P2 in the reactive center loop of SCC antigen-2. On the other hand, the incubation with synthetic peptides having the sequence of the reactive center loop of SCC antigen-1 or antithrombin had no effect on polymerization of SCC antigen-2. These data suggest that the polymerization of SCC antigen-2 may occur spontaneously in vivo by the loop-sheet mechanism of serpin.


Assuntos
Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Serpinas/análise , Antitrombinas/análise , Eletroforese em Gel Bidimensional/métodos , Humanos , Peptídeos/análise , Polímeros , Desnaturação Proteica
8.
Hum Cell ; 14(4): 272-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11925928

RESUMO

Although the International Federation of Gynecology and Obstetrics officially changed the classification system of endometrial cancer from a clinically staged to a surgically staged disease in 1988, optimal management of patients with endometrial cancer is still controversial. Gynecologists happen to experience that patients with tumors that are identical in grade and stage often have significantly different clinical outcomes or responses to therapy. In order to identify an objective biological factor correlating with tumor aggressiveness, many tumor markers have been investigated. So far, CA125 is one of the most reliable tumor marker for adenocarcinoma of the uterus and frequently used in a clinical setting. Recently, with the advent of molecular biological techniques, many genes and regions of the genome related to endometrial cancer have been identified. We undertook a genome-wide screening to detect genetic changes by comparative genomic hybridization (CGH) in primary endometrioid cancers, since CGH analysis provides comprehensive information concerning relative chromosomal losses and gains in tumors by a single hybridization. In this paper, the usefulness of serum tumor markers and the new promising molecular tumor markers for endometrial cancer are discussed.


Assuntos
Biomarcadores Tumorais , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Biomarcadores Tumorais/sangue , Antígeno Ca-125/sangue , Deleção Cromossômica , Feminino , Amplificação de Genes , Marcadores Genéticos , Humanos , Hibridização de Ácido Nucleico/métodos
9.
Tumour Biol ; 21(4): 224-34, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10867615

RESUMO

Squamous cell carcinoma antigen (SCCA) is expressed in normal squamous epithelia and malignant squamous cell tissues. The serum level of SCCA has been used to evaluate treatment efficacy, clinical course of disease, and recurrence. SCCA is produced by at least two genes (SCCA1 and SCCA2); both of them have been located on chromosome 18q21.3. It has been difficult to examine the expression levels of SCCA1 and SCCA2 mRNAs separately because of their high homology at nucleotide level. In the present study, asymmetric semi-nested reverse transcription PCR, based on the principle of fluorescence energy transfer, enabled to quantitate the copy numbers of both SCCA1 and SCCA2 mRNAs. Using this method, the expression levels of these mRNAs were evaluated in normal and malignant squamous tissues. The copy number of SCCA2 mRNA was higher in malignant tissues than in normal tissues, while those of SCCA1 mRNA did not significantly differ between normal and malignant tissues. These data indicate that specific quantitation of the expression level of SCCA2 mRNA may be useful for the diagnosis and management of patients with squamous cell carcinoma.


Assuntos
Antígenos de Neoplasias/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Serpinas , Antígenos de Neoplasias/biossíntese , Sequência de Bases , Biomarcadores Tumorais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/metabolismo , Primers do DNA , DNA Complementar/análise , DNA Complementar/genética , Eletroforese em Gel Bidimensional , Epitélio/química , Feminino , Fluorescência , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sensibilidade e Especificidade , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/química , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
10.
Br J Cancer ; 82(4): 981-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10732775

RESUMO

The squamous cell carcinoma antigen (SCC Ag) is a tumour-associated protein and a member of the serine protease inhibitor (serpin) family. The SCC Ag has been used as a serologic tumour marker for SCC progression, and its elevated serum levels are a risk factor for disease relapse. However, the biologic significance of this intracytoplasmic protein in cancer cells remains unknown. In this report, we demonstrated that apoptosis induced by 7-ethyl-10-hydroxycamptothecin, tumour necrosis factor-alpha (TNF-alpha) or interleukin (IL)-2-activated natural killer (NK) cells was significantly inhibited in tumour cells transduced with the SCC Ag-1 cDNA, as compared to control cells in vitro. Also, inhibition of the SCC Ag-1 expression in tumour cells by transfection of antisense SCC Ag-1 cDNA was accompanied by significantly increased sensitivity of these cells to apoptosis induced by etoposide or TNF-alpha. The mechanism of protection of tumour cells from apoptosis involved inhibition of caspase-3 activity and/or upstream proteases. In vivo, tumour cells overexpressing the SCC Ag-1 formed significantly larger tumours in nude mice than the SCC Ag-1-negative controls. Thus, overexpression of the SCC Ag-1, a member of the serpin family, in human cancer cells contributed to their survival by mediating protection from drug-, cytokine- or effector cell-induced apoptosis.


Assuntos
Antígenos de Neoplasias/imunologia , Apoptose/imunologia , Serpinas , Antígenos de Neoplasias/genética , Apoptose/efeitos dos fármacos , Sequência de Bases , Carcinoma de Células Escamosas/imunologia , Primers do DNA , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia
11.
Electrophoresis ; 20(3): 614-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10217177

RESUMO

The aim of this study was to identify two homologous serine proteinase inhibitor (serpin) molecules, squamous cell carcinoma (SCC) antigen-1 and -2, by two-dimensional electrophoresis (2-DE), combined with immunoblotting, and examine their expression in tumor tissue. The recombinant SCC (rSCC) antigen-1 showed four spots with p/ 6.5, 6.4, 6.3 and 6.0, whereas rSCC antigen-2 showed a more acidic spot with p/5.95. SCC antigen in tumor tissue appeared in three new acidic spots (p/5.7-5.5, M(r) 44 500), numbered 5, 6 and 7, besides the previously reported four spots numbered 1 to 4. These new acidic spots of SCC antigen apparently increased in SCC tissue. Treatment of tissue extract by carboxymethyl (CM)-papain agarose matrix extinguished spots 1 to 4 encoded on the SCCA1 gene, but not 5 to 7 on the SCCA2 gene. Overexpression of the SCCA2 gene may play an important role in the malignant behavior of tumor cells.


Assuntos
Antígenos de Neoplasias/análise , Carcinoma de Células Escamosas/imunologia , Eletroforese em Gel Bidimensional/métodos , Serpinas , Carcinoma de Células Escamosas/patologia , Humanos , Papaína , Proteínas Recombinantes/análise , Sefarose
12.
Biochim Biophys Acta ; 1444(1): 111-6, 1999 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-9931463

RESUMO

The squamous cell carcinoma antigen (SCCA) has been used as a circulating tumor marker for the management of squamous cell carcinoma. SCCA consists of a small gene family of at least two in human genome (SCCA1 and SCCA2), which are tandemly arrayed on chromosome 18q21.3 and share 92% identical residues. SCCA expressions are tightly controlled in a tissue-specific manner. To investigate the role of SCCA2 in the cancer cells, we first isolated the human genomic clones, containing the promoter region of SCCA2 gene, and determined the nucleotide sequence surrounding the exon 1. The transcription start site was mapped by primer extension analysis, and a putative TATA box element was found in the 5'-flanking region. Other putative regulatory sequences, which include Ets binding sequence, NF-IL6 binding sequence and IRE consensus sequence, were also found in the region. Analysis of luciferase reporter gene expression in transient transfection showed that the promoter region of SCCA2 gene was located within the region from -424 to +47.


Assuntos
Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Regiões Promotoras Genéticas , Serpinas , Sequência de Bases , Éxons , Humanos , Dados de Sequência Molecular , RNA Mensageiro/química , Mapeamento por Restrição
13.
Tumour Biol ; 19(6): 454-63, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9817973

RESUMO

The process of metastasis involves a series of sequential steps in which malignant cells are released from the primary tumor and metastasize to distant sites. Syndecan-1 is a cell surface proteoglycan that mediates cell adhesion and undergoes changes upon cell transformation of some cells that may contribute to the process of metastasis. To investigate the possible role of syndecan-1 in cell proliferation and metastatic potential, we employed a highly metastatic cell line (KLN 205) derived from mouse lung squamous cell carcinoma that expressed moderate amounts of syndecan-1. At first, endogenous syndecan-1 production was inhibited by an antisense oligodeoxynucleotides (ODNs). Since antisense ODNs of syndecan-1 inhibited cell growth, we established stable transfectants of syndecan-1 in this cell line to examine a proliferative advantage with the level of syndecan-1 expression. Overexpresser cells grew at a significantly faster rate than the vector-transfected control and showed greater incidence of tumor formation when injected subcutaneously into nude mice. Surprisingly, overexpresser cells enhanced pulmonary metastasis when injected intravenously. These results indicate that syndecan-1 expression plays a role in the control of cell proliferation and suggest that syndecan-1 expression may be involved in facilitating distant metastasis of tumor cells once they managed to enter the bloodstream (after intravasation steps).


Assuntos
Glicoproteínas de Membrana/metabolismo , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Proteoglicanas/metabolismo , Animais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundário , Divisão Celular , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oligonucleotídeos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Sindecana-1 , Sindecanas , Células Tumorais Cultivadas
14.
Tumour Biol ; 19(6): 488-93, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9817978

RESUMO

SCC antigen is a tumor-associated protein of squamous cell carcinoma of various organs. So far, two genes (SCC Ag-1 and SCC Ag-2) have been identified, and their products are highly homologous and classified as serine protease inhibitors (serpin). Recombinant SCC antigen-1 inhibits chymotrypsin and cathepsin L in vitro, indicating that it is inhibitory type serpin. Transduction of tumor cells with SCC antigen-1 reveals that SCC antigen-1 inhibits apoptosis of tumor cells induced by anticancer drug, TNFalpha or NK cells. Therefore SCC antigen-1 may work in cancer cells for tumor growth, and in normal squamous epithelium for differentiation by means of the inhibition of apoptosis. Recombinant SCC antigen-2 inhibits cathepsin G and mast cell chymase, suggesting that it protects epithelial cells from the inflammation induced by these proteases.


Assuntos
Antígenos de Neoplasias/fisiologia , Biomarcadores Tumorais/fisiologia , Serpinas/fisiologia , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Apoptose , Biomarcadores Tumorais/química , Biomarcadores Tumorais/genética , Epitélio/imunologia , Humanos , Inibidores de Proteases , Serpinas/química , Serpinas/genética
15.
Oncogene ; 16(10): 1309-17, 1998 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-9546432

RESUMO

Interleukin-2 (IL-2) is recognized as a T cell growth factor. We have previously reported that human carcinoma cell lines are inhibited in growth by exogenous IL-2, which binds to the IL-2 receptor beta (IL-2Rbeta) chain ubiquitously expressed on the surface of tumor cells. A possibility was considered that IL-2Rbeta on carcinomas responsible for negative signaling was different from that expressed on hematopoietic cells. To investigate this possibility, mRNA for the IL-2Rbeta chain was amplified and compared in carcinoma and lymphoid cells. Using RT-PCR with pairs of sense-antisense oligonucleotide primers specific for the various regions of extracellular, transmembrane and intracellular domains of the IL-2Rbeta chain, we amplified mRNA obtained from three human carcinoma cell lines and human lymphoid cells as controls. The identity of the amplicons was confirmed by Southern analysis with the 32P-labeled cDNA probe coding for the entire span of the IL-2Rbeta chain. In addition, genomic DNA obtained from the tumor cell lines was sequenced to examine the possibility that a mutation is present in the gene coding for the intracellular IL-2Rbeta chain domain. No mutations or deletions were detected. The message for all three domains of the beta chain was identical in tumor cells and in normal lymphoid cells used as controls. Also, by Western blot and northern analyses no differences between IL-2Rbeta chain in tumors vs that expressed in lymphoid cells were demonstrable. The IL-2Rgamma chain, which participates in IL-2/IL-2R signaling pathway, was expressed in tumor cells. Expression of JAK1 transcripts in these cells was comparable to that in lymphocytes. However, RT-PCR analysis identified differences in expression of JAK3 splice variants (B and M) in tumor cells. These differences may be responsible for altered downstream signaling by IL-2. Overall, our data indicate that the same IL-2/IL-2R pathway is operative in human carcinomas and in normal epithelial or lymphoid cells.


Assuntos
Neoplasias/imunologia , Receptores de Interleucina-2/biossíntese , Receptores de Interleucina-2/genética , Carcinoma de Células Renais , Primers do DNA , Neoplasias de Cabeça e Pescoço , Humanos , Janus Quinase 1 , Células Jurkat , Neoplasias Renais , Linfócitos/enzimologia , Linfócitos/imunologia , Substâncias Macromoleculares , Neoplasias/genética , Oligonucleotídeos Antissenso , Reação em Cadeia da Polimerase , Proteínas Tirosina Quinases/biossíntese , RNA Mensageiro/biossíntese , Receptores de Interleucina-2/química , Neoplasias Gástricas , Transcrição Gênica , Células Tumorais Cultivadas
16.
Apoptosis ; 3(3): 155-60, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-14646496

RESUMO

Increased serum levels of alpha1-antichymotrypsin (alpha 1ACT) are observed in some cancer patients, especially those with hepatocellular carcinoma. A possible role of alpha 1ACT in tumour growth has been suggested, but this remains uncertain. We have demonstrated that alpha 1ACT inhibited chymotrypsin-induced apoptosis in rat hepatoma H4 cells. Even low concentrations of chymotrypsin (but not trypsin) induce apoptosis in H4 cells with a minimum effective concentration of 2.4 x 10(-2) units/ml (0.5 microg/ml), and this apoptosis was inhibited by alpha 1ACT in a concentration-dependent manner. Furthermore, the concentrations of alpha 1ACT required to inhibit the apoptosis were lower than normal serum levels. These results may indicate that alpha 1ACT plays a role in the apoptosis of rat hepatoma cells.

17.
Cancer Gene Ther ; 4(6): 366-76, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9408607

RESUMO

Two human squamous cell carcinoma of the head and neck (SCCHN) cell lines, PCI-13 and PCI-52, were transduced with the retroviral construct containing human interleukin-2 (IL-2) cDNA and selected for neomycin resistance in G418 medium. Stably transduced SCCHN cells produced and secreted IL-2, which was shown to have biologic activity in a bioassay, using an IL-2-dependent CTLL-2 cell line. By immunohistochemistry, IL-2 gene-transduced PCI-13 cells were strongly positive for IL-2, and by flow cytometry showed both cell surface and intracytoplasmic expression of IL-2 protein. Expression of IL-2 mRNA was measured by quantitative RT-PCR and found to be considerably increased in transduced SCCHN relative to that in parental cells. There was no difference in expression of IL-2R between the parental and IL-2 gene-transduced cells. In vitro proliferation of IL-2 gene-transduced tumor cells was consistently more rapid than that of parental cells. Sensitivity of the parental and IL-2 gene-transduced targets to lysis or apoptosis mediated by purified human natural killer (NK) cells or IL-2-activated NK (A-NK) cells was comparable as measured in 4-hour 51Cr-release and 1-hour [3H]thymidine-release assays, respectively. However, transduced cells were significantly more sensitive than parental cells to these effectors in 24-hour MTT assays, most likely due to IL-2 production by the transduced targets. PCI-52 cells selected for in vivo experiments formed large subcutaneous tumors in immunosuppressed nude mice. Tumors established by subcutaneous injections of 1 x 10(7) IL-2 gene-transduced cells regressed completely by day 25, while those formed by parental or LacZ gene-transduced tumor cells grew progressively. Tumor regression was mediated by numerous mononuclear cells, identified as murine NK cells and macrophages by immunohistochemistry, which accumulated around the IL-2-secreting, but not parental, tumors within 5-6 days after tumor cell injections. Thus, IL-2 gene-transduced SCCHN cells produce functional IL-2 in vivo in amounts sufficient to support the recruitment to the tumor site and antitumor activity of cytotoxic effector cells. IL-2-secreting SCCHN cells may be a useful component of vaccines designed to induce and sustain effector cell activation at the tumor site.


Assuntos
Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Citotoxicidade Imunológica , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Interleucina-2/biossíntese , Células Matadoras Naturais/imunologia , Animais , Carcinoma de Células Escamosas/terapia , Divisão Celular , Linhagem Celular , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Interleucinas/biossíntese , Cinética , Camundongos , Camundongos Nus , RNA Mensageiro/biossíntese , Proteínas Recombinantes/biossíntese , Transcrição Gênica , Transfecção/métodos , Fator de Crescimento Transformador beta/biossíntese , Transplante Heterólogo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/biossíntese
18.
Int J Cancer ; 72(1): 174-83, 1997 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9212240

RESUMO

We transduced a human gastric carcinoma cell line, HR, with the interleukin 2 (IL-2) gene. Stable HR transfectants secreted nanogram quantities of biologically active IL-2 and had significantly increased expression of IL-2 mRNA relative to that in parental cells. Expression of intracellular IL-2 protein was not quantitatively different in the parental and IL-2 gene-transduced cells, although the former did not secrete IL-2. Surface expression of IL-2 receptors was comparable in the parental and transduced cells at the mRNA or protein levels. Nevertheless, in vitro proliferation of IL-2 gene-transduced HR cells was significantly more rapid than that of parental cells. Both parental and IL-2 gene-transduced HR cells were equally sensitive to lysis by IL-2-activated natural killer (A-NK) cells, as measured in 4 hr 51Cr-release assasys or to apoptosis induced by NK or A-NK cells, assessed in 1 hr 3H-TdR-release assays. In 24 hr MTT assays, however, the IL-2 gene-transduced cells were significantly more sensitive to these effector cells than were parental cells. Upon intrasplenic injection of 5 x 10(6) parental or transduced HR cells into nude mice, liver metastases developed. Metastases of parental HR cells killed the animals in 24 days. In contrast, metastases of the IL-2 gene-transduced HR cells became necrotic by day 14 and were found to be surrounded by murine NK cells and macrophages. Survival of nude mice injected with IL-2 gene-transduced HR cells was significantly prolonged (>50 days) relative to that of mice injected with parental HR. Thus, IL-2 gene-transduced HR cells produced sufficient amounts of functional IL-2 in vivo to be able to recruit to the tumor site and support functions of endogenous cytotoxic immune effector cells, which were responsible for regression of hepatic metastases and significant improvement of survival in these mice.


Assuntos
Interleucina-2/genética , Neoplasias Gástricas/genética , Animais , Divisão Celular , Testes Imunológicos de Citotoxicidade , Humanos , Interleucina-2/biossíntese , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Camundongos , Camundongos Nus , Transplante de Neoplasias , RNA Mensageiro/metabolismo , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/mortalidade , Transdução Genética , Células Tumorais Cultivadas
19.
Electrophoresis ; 18(5): 784-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9194607

RESUMO

We investigated the "cross-class" interaction between cysteine proteinases and a novel inhibitory serpin, recombinant squamous cell carcinoma (rSCC) antigen-1, which inhibits a serine proteinase, chymotrypsin. rSCC antigen-1 inhibited the cysteine proteinases, papain, papaya proteinase IV and cathepsin L. Interestingly, although rSCC antigen-1 formed sodium dodecyl sulfate (SDS)- and heat-stable complexes with chymotrypsin, rSCC antigen-1 gave the 40 kDa fragment and small molecular mass peptide by incubation with papain without forming an SDS- and heat-stable complex. The cleavage was observed between the Gly353-Ser354 bond, indicating that rSCC antigen-1 interacts with cysteine proteinases not at the predicted reactive site P1-P1' portion (Ser354-Ser355), but at the Gly353-Ser354 of the P2-P1 portion. These findings promote understanding of the "suicide inhibition" mechanism of SCC antigen-1 against cysteine proteinases.


Assuntos
Antígenos de Neoplasias/farmacologia , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Eletroforese em Gel de Poliacrilamida/métodos , Serpinas/farmacologia , Animais , Antígenos de Neoplasias/genética , Sítios de Ligação , Quimotripsina/antagonistas & inibidores , Lisossomos/enzimologia , Papaína/antagonistas & inibidores , Conformação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Serpinas/genética
20.
Arch Gynecol Obstet ; 259(3): 133-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9187465

RESUMO

Twenty-three patients undergoing pelvic exenteration for primary and recurrent gynecological malignancies from 1976 to 1994 are reported. Fifteen patients underwent total pelvic exenteration, 3 underwent anterior exenteration, and 5 underwent a posterior procedure. Eight patients had exenteration as their primary treatment (primary group), and 15 underwent exenteration as secondary treatment (recurrent group). In the primary group, two patients developed recurrence and died of it at 6 and 20 months after operation. Five patients are still being followed up and are alive without disease. Four of these 5 patients have survived more than 5 years. In the recurrent group, 12 patients were followed up and three died of complications during the early years. Seven patients died of cancer with the mean survival time of 16.6 months. The mean age, average operating time, and mean blood loss in the primary and recurrent groups were 57 vs. 53 years, 8 hours and 20 min vs. 8 hours and 10 min, and 4,120 vs. 4,190 ml, respectively. The overall cumulative 5-year survival rate was 34.7%, being 68.6% in the primary group and 16.7% in the recurrent group. It is noteworthy that the 5-year survival rate was 51.3% in the patients who had surgical margins free of disease. In conclusion, pelvic exenteration should be considered an acceptable therapeutic option when appropriately selected.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Exenteração Pélvica , Adulto , Idoso , Perda Sanguínea Cirúrgica , Feminino , Neoplasias dos Genitais Femininos/mortalidade , Neoplasias dos Genitais Femininos/patologia , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Qualidade de Vida , Recidiva , Taxa de Sobrevida , Fatores de Tempo
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