interleukin-8 has been researched along with Fibrosarcoma* in 14 studies
14 other study(ies) available for interleukin-8 and Fibrosarcoma
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Lurbinectedin reduces tumour-associated macrophages and the inflammatory tumour microenvironment in preclinical models.
Lurbinectedin is a novel anticancer agent currently undergoing late-stage (Phase II /III) clinical evaluation in platinum-resistant ovarian, BRCA1/2-mutated breast and small-cell lung cancer. Lurbinectedin is structurally related to trabectedin and it inhibits active transcription and the DNA repair machinery in tumour cells.. In this study we investigated whether lurbinectedin has the ability to modulate the inflammatory microenvironment and the viability of myeloid cells in tumour-bearing mice.. Administration of lurbinectedin significantly and selectively decreased the number of circulating monocytes and, in tumour tissues, that of macrophages and vessels. Similar findings were observed when a lurbinectedin-resistant tumour variant was used, indicating a direct effect of lurbinectedin on the tumour microenviroment. In vitro, lurbinectedin induced caspase-8-dependent apoptosis of human purified monocytes, whereas at low doses it significantly inhibited the production of inflammatory/growth factors (CCL2, CXCL8 and VEGF) and dramatically impaired monocyte adhesion and migration ability. These findings were supported by the strong inhibition of genes of the Rho-GTPase family in lurbinectedin-treated monocytes.. The results illustrate that lurbinectedin affects at multiple levels the inflammatory microenvironment by acting on the viability and functional activity of mononuclear phagocytes. These peculiar effects, combined with its intrinsic activity against cancer cells, make lurbinectedin a compound of particular interest in oncology. Topics: Animals; Antineoplastic Agents, Alkylating; Apoptosis; Carbolines; Caspase 8; Cell Adhesion; Cell Movement; Chemokine CCL2; Dioxoles; Down-Regulation; Female; Fibrosarcoma; Gene Expression; Gene Expression Profiling; Heterocyclic Compounds, 4 or More Rings; HL-60 Cells; Humans; Interleukin-8; Leukocyte Count; Macrophages; Mice; Mice, Inbred C57BL; Monocytes; Neovascularization, Pathologic; Ovarian Neoplasms; rho GTP-Binding Proteins; Tetrahydroisoquinolines; Trabectedin; Tumor Microenvironment; U937 Cells; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays | 2017 |
Tumor-recruited neutrophils and neutrophil TIMP-free MMP-9 regulate coordinately the levels of tumor angiogenesis and efficiency of malignant cell intravasation.
Tumor-associated neutrophils contribute to neovascularization by supplying matrix metalloproteinase-9 (MMP-9), a protease that has been genetically and biochemically linked to induction of angiogenesis. Specific roles of inflammatory neutrophils and their distinct proMMP-9 in the coordinate regulation of tumor angiogenesis and tumor cell dissemination, however, have not been addressed. We demonstrate that the primary tumors formed by highly disseminating variants of human fibrosarcoma and prostate carcinoma recruit elevated levels of infiltrating MMP-9-positive neutrophils and concomitantly exhibit enhanced levels of angiogenesis and intravasation. Specific inhibition of neutrophil influx by interleukin 8 (IL-8) neutralization resulted in the coordinated diminishment of tumor angiogenesis and intravasation, both of which were rescued by purified neutrophil proMMP-9. However, if neutrophil proMMP-9, naturally devoid of tissue inhibitor of metalloproteinases (TIMP), was delivered in complex with TIMP-1 or in a mixture with TIMP-2, the protease failed to rescue the inhibitory effects of anti-IL8 therapy, indicating that the TIMP-free status of proMMP-9 is critical for facilitating tumor angiogenesis and intravasation. Our findings directly link tumor-associated neutrophils and their TIMP-free proMMP-9 with the ability of aggressive tumor cells to induce the formation of new blood vessels that serve as conduits for tumor cell dissemination. Thus, treatment of cancers associated with neutrophil infiltration may benefit from specific targeting of neutrophil MMP-9 at early stages to prevent ensuing tumor angiogenesis and tumor metastasis. Topics: Animals; Cell Line, Tumor; Chick Embryo; Enzyme Precursors; Fibrosarcoma; Humans; Interleukin-8; Male; Matrix Metalloproteinase 9; Mice; Mice, Nude; Mice, SCID; Neoplasm Invasiveness; Neovascularization, Pathologic; Neutrophils; Prostatic Neoplasms; Tissue Inhibitor of Metalloproteinases | 2011 |
The myxoid liposarcoma FUS-DDIT3 fusion oncoprotein deregulates NF-kappaB target genes by interaction with NFKBIZ.
FUS (also called TLS), EWSR1 and TAF15 (also called TAF2N) are related genes involved in tumor type-specific fusion oncogenes in human malignancies. The FUS-DDIT3 fusion oncogene results from a t(12;16)(q13;p11) chromosome translocation and has a causative role in the initiation of myxoid/round cell liposarcomas (MLS/RCLS). The FUS-DDIT3 protein induces increased expression of the CAAT/enhancer-binding protein (C/EBP) and nuclear factor-kappaB (NF-kappaB)-controlled gene IL8, and the N-terminal FUS part is required for this activation. Chromatin immunoprecipitation analysis showed that FUS-DDIT3 binds the IL8 promoter. Expression studies of the IL8 promoter harboring a C/EBP-NF-kappaB composite site pinpointed the importance of NF-kappaB for IL8 expression in FUS-DDIT3-expressing cells. We therefore probed for possible interaction of FUS-DDIT3 with members of the NF-kappaB family. The nuclear factor NFKBIZ colocalizes with FUS-DDIT3 in nuclear structures, and immunoprecipitation experiments showed that FUS-DDIT3 binds the C-terminal of NFKBIZ. We also report that additional NF-kappaB-controlled genes are upregulated at the mRNA level in FUS-DDIT3-expressing cell lines and they can be induced by NFKBIZ. Taken together, the results indicate that FUS-DDIT3 deregulates some NF-kappaB-controlled genes through interactions with NFKBIZ. Similar mechanisms may be a part of the transformation process in other tumor types carrying FUS, EWSR1 and TAF15 containing fusion oncogenes. Topics: Acute-Phase Proteins; Adaptor Proteins, Signal Transducing; Binding Sites; CCAAT-Enhancer-Binding Proteins; Cell Line, Tumor; Cell Nucleus; Fibrosarcoma; Humans; I-kappa B Proteins; Interleukin-6; Interleukin-8; Lipocalin-2; Lipocalins; Liposarcoma, Myxoid; Neoplasm Proteins; NF-kappa B; Nuclear Proteins; Oncogene Proteins, Fusion; Promoter Regions, Genetic; Protein Binding; Protein Interaction Mapping; Proto-Oncogene Proteins; RNA-Binding Protein FUS; Transcription Factor CHOP; Transcription, Genetic | 2009 |
Dose-dependent effects of dietary alpha- and gamma-tocopherols on genetic instability in mouse Mutatect tumors.
Vitamin E in foodstuffs is a mixture of tocopherols. In mouse Mutatect tumors, a model designed to detect DNA mutations, the hypoxanthine phosphoribosyltransferase (Hprt) gene mutation frequency is associated with the number of tumor-infiltrating neutrophils and both are markedly decreased in mice fed high levels of alpha-tocopherol. Dietary alpha-tocopherol is also associated with a decrease in neutrophil-associated loss of an interleukin 8 (IL-8)-expressing transgene in this tumor model. We examined Hprt gene mutation frequency (expressed as the number of 6-thioguanine-resistant colonies per 10(5) clonable tumor cells), IL-8 transgene loss, and myeloperoxidase activity (an indirect measure of neutrophil number) in tumors from Mutatect mice fed diets supplemented with various concentrations of D-alpha-tocopherol acetate and/or D-gamma-tocopherol acetate or neither tocopherol for 4 weeks. Hprt gene mutation frequency and myeloperoxidase activity were statistically significantly lower in tumor cells from mice fed alpha-tocopherol at 50 or 100 mg/kg body weight per day than in tumor cells from mice fed 0 mg/kg body weight per day alpha-tocopherol (P<.001 for each comparison). IL-8 transgene loss occurred in 28 of 28 tumors (100%; 95% confidence interval [CI] = 86% to 100%) from mice fed alpha-tocopherol at 50 mg or less/kg body weight per day and seven of 18 tumors (39%; 95% CI = 24% to 54%) from mice fed 100 mg/kg body weight per day (P<.001, Fisher's exact test, referent groups [pooled] 0, 25, and 50 mg/kg). gamma-Tocopherol had no detectable effect on any of the three endpoints. Thus, dietary alpha-tocopherol decreases two forms of genetic instability in a dose-dependent manner in this experimental tumor model. Topics: alpha-Tocopherol; Analysis of Variance; Animals; Animals, Genetically Modified; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Drug; Fibrosarcoma; gamma-Tocopherol; Hypoxanthine Phosphoribosyltransferase; Interleukin-8; Mice; Mutation; Neoplasm Transplantation; Neoplasms, Experimental; Peroxidase; Transgenes; Vitamin E | 2004 |
Dietary vitamin E affects neutrophil distribution and genetic instability in murine Mutatect tumors.
Vitamin E is best known for its ability to scavenge reactive oxygen and nitrogen species. Solid tumors are frequently infiltrated with leukocytes, a potential source of these reactive species. The Mutatect tumor model is a fibrosarcoma that can be grown subcutaneously in syngeneic C57BL/6 mice. We previously showed that these tumors are infiltrated with neutrophils and that the number of neutrophils correlates with the number of hypoxanthine phosphoribosyl transferase (hprt) mutations and loss of an interleukin-8 (IL-8) transgene. Neutrophils are a source of nitric oxide, and tumors contain nitrotyrosine, a marker of damage by nitric oxide-related species. We also showed previously that dietary vitamin E supplements markedly lower the frequency of hprt mutants and the level of myeloperoxidase (a neutrophil marker) in a tumor fraction containing "loosely bound" cells. In the present report, we examine the effect of dietary vitamin E in greater detail. No effect on inducible nitric oxide synthase expression or nitrotyrosine levels was observed. However, dietary vitamin E induced a major redistribution of neutrophils from the loosely bound cellular fraction to the "stromal" fraction, while the total number of neutrophils in tumors was essentially unchanged. The loss of the IL-8 transgene seen earlier in Mutatect tumors was largely prevented. Vitamin E also prevented the large increase in hprt mutants (in the cellular and stromal fractions). Thus vitamin E appears to be protective against genotoxicity by scavenging reactive species, but also its ability to affect the distribution of neutrophils within tumors may be important. Topics: Animals; Diet; Female; Fibrosarcoma; Hypoxanthine Phosphoribosyltransferase; Interleukin-8; Mice; Mice, Inbred C57BL; Mutation; Neutrophils; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Transgenes; Tyrosine; Vitamin E | 2002 |
Selective nitration of histone tyrosine residues in vivo in mutatect tumors.
Nitric oxide-derived reactive species have been implicated in many disorders. Protein nitrotyrosine is often used as a stable marker of these reactive species. Using immunohistochemistry, we have previously detected nitrotyrosine in murine Mutatect tumors, where neutrophils are the principal source of nitric oxide. We now report on the identification of several prominent nitrotyrosine-containing proteins. Using Western blot analysis, nitrotyrosine in higher molecular mass proteins (>20 kDa) was detected in tumors containing a high number of neutrophils but not in tumors with fewer neutrophils. Staining for nitrotyrosine was consistently seen in low molecular mass proteins (< or =15 kDa), regardless of the level of neutrophils. Protein nitrotyrosine was not seen in Mutatect cells growing in vitro. Treatment with nitric oxide donors produced nitration of < or =15-kDa proteins, but only after extended periods. These small proteins, both from tumors and cultured cells, were identified by mass spectrometry to be histones. Only a subset of tyrosine residues was nitrated. Selective nitration may reflect differential accessibility of different tyrosine residues and the influence of neighboring residues within the nucleosome. The prominence of histone nitration may reflect its relative stability, making this post-translational modification a potentially useful marker of extended exposure of cells or tissues to nitric oxide-derived reactive species. Topics: Animals; Blotting, Western; Fibrosarcoma; Histones; Interleukin-2; Interleukin-8; Mice; Neutrophils; Nitric Oxide; Nitrites; Nucleosomes; Tumor Cells, Cultured; Tyrosine | 2002 |
Constitutive expression of interleukin-8 by Mutatect cells markedly affects their tumor biology.
Interleukin-8 (IL-8) is a chemokine for neutrophils and an angiogenic factor. Human tumors that express IL-8 may exhibit intense neutrophil infiltration and increased vascularization. Mutatect cells are a murine fibrosarcoma that can be grown as subcutaneous tumors in syngeneic C57BL/6 mice. Since neutrophils are a source of cytotoxic and genotoxic species, we constructed Mutatect cell lines that constitutively express human IL-8 to explore the involvement of neutrophils in tumor biology and genetic instability. An IL-8/neo expression plasmid was stably transfected into Mutatect MC17-51 cells and clone MIL-4 was isolated. Tumors initiated with 5x10(5) MIL-4 cells grew very slowly compared with tumors from pure MC17-51 cells or from 0.5 to 4x10(5) MIL-4 cells mixed with 5x10(5) MC17-51 cells. Over 95% of cells recovered from slow-growing pure MIL-4 tumors lost the transgene as measured by loss of (i) resistance to G418, (ii) expression of IL-8 protein and (iii) IL-8-specific DNA sequences. When tumors from mixed cell types were examined, loss of the transgene did not occur; rather, IL-8 producing cells appeared to have some growth advantage. The neutrophil content of tumors (as measured by myeloperoxidase) was directly proportional to the level of IL-8 expressed at the time tumors were excised. As reported earlier, the frequency of mutations at the hypoxanthine phosphoribosyltransferase locus was also directly proportional to neutrophil content. To explain some of these biological findings, we postulate that early in development of pure MIL-4 tumors, genotoxic/cytotoxic neutrophils are attracted by IL-8, which in turn leads to loss of the transgene and to localized cytotoxicity of IL-8 producing cells. In mixed tumors, where the initial IL-8 concentration may be lower, tumors might become established more readily because fewer neutrophils may be attracted. This relatively simple experimental paradigm has revealed some of the complex biological changes that can occur as a result of IL-8 in tumors. Topics: Animals; Cell Division; Drug Resistance; Enzyme-Linked Immunosorbent Assay; Fibrosarcoma; Genetic Vectors; Gentamicins; Humans; Injections, Subcutaneous; Interleukin-8; Mice; Mice, Inbred C57BL; Mutation; Neoplasm Transplantation; Neutrophils; Peroxidase; Polymerase Chain Reaction; Skin Neoplasms; Transfection; Tumor Cells, Cultured | 2001 |
Neutrophils, nitric oxide synthase, and mutations in the mutatect murine tumor model.
Mutatect MN-11 is a tumor line that can be grown subcutaneously in syngeneic C57BL/6 mice. The frequency of spontaneously arising mutants at the hypoxanthine phosphoribosyltransferase (Hprt) locus was observed to be elevated as a result of in vivo growth. The objective of the present study was to identify factors in the tumor microenvironment that might explain this increase in mutant frequency (MF). When tumors were examined histologically, neutrophils were found to be the predominant infiltrating cell type. Quantitative estimates of the number of neutrophils and MF of tumors in different animals revealed a statistically significant correlation (r = 0.63, P < 0.0001). Immunohistochemical analysis for inducible nitric oxide synthase (iNOS) demonstrated its presence, mainly in neutrophils. Biochemical analysis of tumor homogenates for nitric oxide synthase (NOS) activity indicated a statistically significant correlation with MF (r = 0.77, P < 0.0001). Nitrotyrosine was detected throughout the tumor immunohistochemically; both cytoplasmic and nuclear staining was seen. To increase the number of infiltrating neutrophils, tumors were injected with chemoattractant interleukin-8 and prostaglandin E2. This produced a statistically significant increase in neutrophil content (P = 0.005) and MF (P = 0.0002). As in control MN-11 tumors, neutrophil content and MF were strongly correlated (r = 0.63, P = 0. 003). Because neutrophils are a potential source of genotoxic reactive oxygen and/or nitrogen species, our results support the notion that these tumor-infiltrating cells may be mutagenic and contribute to the burden of genetic abnormalities associated with tumor progression. Topics: Animals; Cell Movement; Dinoprostone; Drug Combinations; Female; Fibrosarcoma; Gene Frequency; Genetic Variation; Immunohistochemistry; Injections; Injections, Subcutaneous; Interleukin-8; Mice; Mice, Inbred C57BL; Mutation; Neoplasm Transplantation; Neutrophils; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Tumor Cells, Cultured; Tyrosine | 2000 |
Thioredoxin as a potent costimulus of cytokine expression.
Reduction/oxidation (redox) processes have been implicated in various biologic processes, including signal transduction, gene expression, and cell proliferation. Thioredoxin is one of the major redox-regulatory molecules which because of its dithiol/disulfide exchange activity determines the oxidation state of protein thiols. In this study, we report that treatment of several cell types with thioredoxin strongly enhances the expression of various cytokines. In monocytic Mono Mac6 cells stimulated with the phorbolester tetradecanoyl phorbolacetate (TPA), thioredoxin was found to augment the expression of TNF at the protein and mRNA levels. In this and other cell lines, such as fibrosarcoma and endothelial cells, thioredoxin also dose-dependently increased the synthesis of IL-6. Treatment of TPA-stimulated Mono Mac6 cells resulted in a strong potentiation of secreted IL-1 bioactivity and expression of IL-1 alpha and IL-8 mRNA. In addition, in TPA-activated Molt-4 T cells, an increased expression of IL-2 and IL-2-specific transcripts was detected. These data demonstrate that cytokine synthesis may be tightly controlled by redox-dependent processes. As thioredoxin is readily secreted and taken up by cells, it may play an important role as a costimulatory molecule involved in immune processes. Topics: Animals; CD4-Positive T-Lymphocytes; Cell Line; Cytokines; Fibrosarcoma; Gene Expression Regulation; Hematopoietic Stem Cells; Interleukin-1; Interleukin-6; Interleukin-8; Mice; Monocytes; Oxidation-Reduction; Recombinant Fusion Proteins; RNA, Messenger; Stimulation, Chemical; Tetradecanoylphorbol Acetate; Thioredoxins; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha | 1996 |
Retinoic acid induces cells cultured from oral squamous cell carcinomas to become anti-angiogenic.
Retinoids have shown great promise as chemopreventive against the development of squamous cell carcinomas of the upper aerodigestive tract. However, the exact mechanism by which they block new tumors from arising is unknown. Here, we report that 13-cis- and all-trans-retinoic acid, used at clinically achievable doses of 10(-6) mol/L or less, can directly and specifically affect cell lines cultured from oral squamous cell carcinomas, inducing them to switch from an angiogenic to an anti-angiogenic phenotype. Although retinoic-acid-treated and untreated tumor cells make the same amount of interleukin-8, the major inducer of neovascularization produced by such tumor lines, they vary in production of inhibitory activity. Only the retinoic-acid-treated cells produce a potent angio-inhibitory activity that is able to block in vitro migration of endothelial cells toward tumor cell conditioned media and to halt neovascularization induced by such media in the rat cornea. Anti-angiogenic activity is induced in the tumor cells by low doses of retinoids in the absence of toxicity with a kinetics that suggest that it could be contributing to the effectiveness of the retinoids as chemopreventive agents. Topics: Animals; Breast Neoplasms; Carcinoma, Squamous Cell; Colonic Neoplasms; Cornea; Endothelium, Vascular; Female; Fibrosarcoma; Humans; Interleukin-8; Keratinocytes; Neovascularization, Pathologic; Neovascularization, Physiologic; Neutralization Tests; Phenotype; Rats; Rats, Inbred F344; Tongue Neoplasms; Transforming Growth Factor beta; Tretinoin; Tumor Cells, Cultured | 1996 |
Local hyperthermia abrogates the anti-immunotherapeutic effect of interleukin-8.
The therapeutic efficacy of cellular immunotherapy depends not only on the anti-tumor activity of the administered effector cells but also on their ability to gain access to the tumor by extravasation. Although interleukin-8 (IL-8) has been shown to prevent the vascular leak associated with IL-2, it also abrogates the anti-tumor effect of IL-2. We undertook these studies to determine if LHT could abrogate the anti-immunotherapeutic effect of IL-8, since IL-8 inhibits leukocyte adhesion. C57BL/6 mice were divided into four groups of six animals each after induction of MCA-105 fibrosarcoma inoculated into the right hindlimb on day 0 and were treated beginning on day 3 as follows: no therapy, IL-2 alone (1.02 x 10(6) IU ip tid on days 3-7), IL-2 + IL-8 (9.6 ng ip tid on days 3-7), and IL-2 + IL-8 + LHT (45C x 15 min on days 3, 5, and 7). Tumor growth was measured on days 10-21 and analyzed by Wilcoxon rank-sum analysis. IL-2 reduced tumor growth significantly (P < .05) compared to no therapy, and IL-8 abrogated the anti-tumor effect of IL-2, resulting in tumor growth in animals receiving IL-2 + IL-8, similar to the no therapy group (P > .05). However, addition of LHT to IL-2 + IL-8 resulted in significantly (P < .05) less tumor growth than no therapy or IL-2 + IL-8. Activity of the mice was scored as an indicator of systemic toxicity. We found that IL-8 was able to increase the activity (P = .07) of the mice when administered with IL-2. These results suggest that IL-8 may protect the tumor-bearing animal from the systemic toxicity of IL-2, while LHT abrogates the anti-immunotherapeutic effect of IL-8. Topics: Animals; Capillary Permeability; Cell Adhesion; Combined Modality Therapy; Female; Fibrosarcoma; Hyperthermia, Induced; Interleukin-2; Interleukin-8; Killer Cells, Lymphokine-Activated; Mice; Mice, Inbred C57BL | 1994 |
Interleukin-8 suppresses the toxicity and antitumor effect of interleukin-2.
The clinical application of interleukin-2 (IL-2) for the treatment of certain human malignancies has shown promise. However, the use of IL-2 in immunotherapeutic protocols has been limited due to its associated toxicities. The administration of therapeutic doses of IL-2 results in a vascular leak syndrome with associated multiple system organ edema, hypotension, and respiratory, renal, and hepatic dysfunction. Previous studies suggest that the mechanism of these toxicities involves the activation of both immune effector cells and the microvascular endothelium with resultant leukocyte-vessel wall interaction, endothelial cell injury, and subsequent invasion of normal tissues by activated leukocytes. Recently it has been demonstrated that interleukin-8 (IL-8) will inhibit leukocyte adherence to an activated endothelium. Thus, we hypothesized that IL-8 would ameliorate IL-2-evoked detrimental effects. We also investigated the influence of IL-8 on IL-2-induced antitumor efficacy. Four groups of nontumored, female, C57BL/6 mice and four groups of C57BL/6 mice with pulmonary metastases from a 3-methylcholanthrene-induced fibrosarcoma (MCA-105) were treated every 6 hr for 4 days by intraperitoneal injections of IL-2 alone, IL-2 and IL-8, IL-8 alone, or an equal volume of saline which served as our control. Upon completion of therapy, we found that IL-8 suppressed many of the IL-2-induced effects including multiple organ edema, hepatic dysfunction, leukopenia, and lymphocytic infiltration of normal organs. When the number of pulmonary metastases were counted 20 days after the cessation of therapy. IL-8 was also found to significantly ablate the IL-2-elicited antitumor efficacy.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Animals; Chemical and Drug Induced Liver Injury; Edema; Female; Fibrosarcoma; Interleukin-2; Interleukin-8; Leukopenia; Lung Neoplasms; Lymphocytes; Methylcholanthrene; Mice; Mice, Inbred C57BL; Neoplasms, Experimental; Tumor Necrosis Factor-alpha | 1994 |
Molecular analysis of the inhibition of interleukin-8 production by dexamethasone in a human fibrosarcoma cell line.
In order to analyse the effects of glucocorticoids on interleukin-8 (IL-8) production more precisely, we examined the effects of dexamethasone on IL-8 production at the molecular level in a human fibrosarcoma cell line, 8387, which IL-1 induces to express IL-8 messenger RNA (mRNA) and to secrete IL-8. Over a wide dose range, dexamethasone inhibited IL-8 production induced by IL-1 alpha stimulation. Northern blotting analysis showed that dexamethasone also inhibited the IL-8 mRNA accumulation in a similar dose-related manner. Nuclear run-off assay revealed that dexamethasone decreased the transcription of the IL-8 gene and the degree of inhibition of transcription correlated well with the inhibition of IL-8 production, suggesting that the action of glucocorticoids is mainly at the transcriptional level. Furthermore, transfection with chloramphenicol acetyl transferase (CAT) expression vectors inserted with the 5'-deleted IL-8 gene demonstrated that the 5'-flanking region which contains the glucocorticoid response element (GRE) was mainly involved in the dexamethasone-induced repression of the IL-8 gene. These data suggest that the inhibition of the IL-8 gene transcription by glucocorticoids occurs through the interaction of the glucocorticoid receptor complex with GRE in the 5'-flanking region of the IL-8 gene. Topics: Blotting, Northern; Cell Line; Dexamethasone; Fibrosarcoma; Humans; Interleukin-8; RNA, Messenger; Transcription, Genetic; Tumor Cells, Cultured | 1992 |
Antitumor effector mechanism of interleukin-1 beta at a distant site in the double grafted tumor system.
Recombinant human interleukin-1 beta (IL-1 beta) inhibited the growth of not only the right, but also the left non-treated tumor in a double grafted tumor system. Since the antitumor activity of IL-1 beta against the right and left tumors was not seen in nude mice, lymphocytes have a key role in the antitumor effect of intratumoral administration of IL-1 beta. TIL (tumor-infiltrating leukocytes) obtained from left and right side tumors treated with IL-1 beta were examined by Winn assay for their antitumor activity against Meth-A sarcoma in BALB/c mice. TIL from the right side clearly inhibited the growth of admixed Meth-A cells, but control TIL did not. Spleen cells and right and left regional lymph node cells prepared from IL-1-treated mice were examined for Lyt-1, Lyt-2 and L3T4 phenotypes. The number of Lyt-1-positive lymphocytes increased in the spleen and in the right regional lymph nodes after intratumoral administration of IL-1. Isolated tumor cells obtained from the right tumor treated with IL-1 beta and the left side tumor on day 6 were cultured in RPMI 1640 with 10% fetal calf serum for 24 h. The culture supernatants were harvested and tested for the presence of chemotactic activity for neutrophils or macrophages. Significant neutrophil chemotactic factor and macrophage chemotactic factor activities were detected in the culture media from IL-1-treated tumor tissues cultured for 24 h. Neither significant neutrophil nor macrophage chemotactic activity was detected in the media from untreated tumor tissues. These results suggest that intratumoral administration of IL-1 first induces neutrophils and macrophages in the right tumor, then Lyt-1-positive cells in the right regional lymph nodes and in the spleen, and subsequently induces macrophages in the left, non-treated tumor. Topics: Animals; Fibrosarcoma; Humans; Immunoglobulin G; Injections; Interleukin-1; Interleukin-8; Lymph Nodes; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neutralization Tests; Recombinant Proteins; Sarcoma, Experimental; Spleen | 1991 |