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1.
We demonstrated that four human oesophageal squamous cell carcinoma cell lines (TE8, TE9, TE10 and TE11) produced matrix metalloproteinase-1 (proMMP-1/tissue collagenase), 2 (ProMMP-2/''type IV collagenase''), 3 (proMMP-3/stromelysin), and 9 (proMMP-9/92-kDa gelatinase) as members of a matrix metalloproteinase (MMP) family, which degrades extracellular matrix macromolecules. Under normal culture conditions, in immunoblot analysis, proMMP-1 of M(r) = 53,00 was detected in one cell line (TE8), proMMP-2 of M(r) = 72,000 in three cell lines (TE9, TE10, and TE11), and proMMP-3 of M(r) = 57,000 in all four cell lines. In addition to these enzymes, in enzymography, a gelatinolytic activity around M(r) = 92-kDa, likely to be proMMP-9, was detected in only one cell line (TE10) under normal culture conditions. When these cell lines were treated with epidermal growth factor (EGF), however, the agent stimulated three cell lines (TE8, TE10 and TE11) to produce proMMP-9 in a dose-dose dependent manner. Oesophageal carcinoma-conditioned medium stimulated oesophageal fibroblasts to produce proMMP-1, -2, and -3, suggesting that the interaction between oesophageal carcinoma and stromal fibroblasts also plays a role in the production of MMPs by the latter. Our present study illustrates that oesophageal squamous cell carcinoma produces a variety of MMPs including proMMP-1, -2, -3, and -9 in vitro, suggesting that the ability of MMP production of the tumour may play an important role in its malignant behaviour and that the production of proMMP-9 may be regulated by EGF via overexpression of EGF receptors.  相似文献   

2.
Expression of extracellular matrix-degrading proteases is required for tumor cell invasion. In the present study we examined the production of type I collagen-degrading matrix metalloproteinases (MMPs) in the invasive oral squamous cell carcinoma-derived cell line HSC-3. In the absence of serum or exogenous growth factors, HSC-3 cells displayed no collagen degradation activity. Addition of serum slightly increased collagen proteolysis. However, addition of epidermal growth factor (EGF) resulted in nearly complete degradation of the collagen matrix. Zymography showed that MMP-2 and -9 are secreted by HSC-3 cells. EGF stimulated secretion of an additional gelatinase with a molecular weight similar to that of MMP-1. Immunoblotting of conditioned medium confirmed that EGF and, to a lesser degree type I collagen, increased production of MMP-1. Finally, in situ hybridization revealed intense expression of MMP-1 in oral squamous cell carcinoma specimens. Together, these results indicate that MMP-1 is expressed, induced by EGF, and required for type I collagen degradation in oral squamous cell carcinoma.  相似文献   

3.
We investigated the growth-regulatory mechanism of 2 esophageal squamous-cancer cell lines, TE2-NS and TE3-OS cells, both of which can grow stably in protein-free conditions in vitro. Protein-free conditioned media from TE2-NS and TE3-OS cells stimulated the growth of these cells. Exogenous epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), insulin-like growth factor (IGF)-I and -II enhanced cell proliferation by 2.2- to 3.8-fold in protein-free conditions, as compared with an untreated control. Receptor-binding assays showed that both TE2-NS and TE3-OS cells possessed a single class of high-affinity binding sites for IGF-I and 2 classes of binding sites for TGF-α, as confirmed on the cell membrane by immunochemistry. These results suggest that EGF, TGF-α and IGFs are candidates for the autocrine growth factor in cancer cells. The addition of inhibitory monoclonal antibodies against TGF-a and EGFR, but not those against either EGF or IGF-IR, significantly inhibited growth of the cells. Immunocytochemical staining and ELISA of the conditioned media both confirmed the production of TGF-α protein, but not EGF protein, in these cell lines. The data for a protein-free culture system strongly suggested that TGF-α, but not EGF or IGF, is biologically important as an autocrine growth factor in the growth of these cell lines in vitro.  相似文献   

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5.
The EGF family of proteins encompasses several polypeptides such as epidermal growth factor (EGF), transforming growth factor alpha (TGFα), amphiregulin (AR) and heregulin (HRG-β1). These polypeptides regulate proliferation in breast cancer cells through interaction with membrane receptors. It has been previously shown that high EGF receptor number correlates with aggressive behavior and increased metastasis in human breast cancer. In the present study, we investigated the association between EGF and EGF-like ligand-induced DNA synthesis and secretion of MMP-9 and MMP-2 in metastatic SKBR-3 cells and non-metastatic MCF-7 breast cancer cells. Exposure of SKBR-3 cells to EGF or Ar induces expression of MMP-9 but has no effect on MMP-2 secretion. In contrast to EGF and AR, HRG had no effect on gelatinase induction. None of the EGF polypeptides had any effect on gelatinase induction in MCF-7 non-metastatic breast cancer cells. While a relatively specific inhibitor of EGF receptor tyrosine kinase, PD 153035, inhibited EGF-, AR- and HRG-induced cell proliferation, it had no effect on MMP-9 induced by EGF and AR. Experimental evidence suggest that signalling mechanisms for cell proliferation and MMP-9 induction are mediated by different pathways down-stream of EGF receptor autophosphorylation or that low levels of EGF- induced signal that escape inhibition are sufficient to induce MMP-9 but unable to support cell proliferation. In addition, our results suggest that EGF and AR may modulate invasion of metastatic breast cancer cells by increasing the expression of MMPs. Int. J. Cancer 70:722–726, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

6.
Previous studies have established that colon carcinoma cells secrete several polypeptide growth factors, including TGF-alpha/EGF and TGF-beta, suggesting that these and related molecules function in an autocrine/paracrine fashion to modulate tumor-cell growth. To investigate this possibility, we have studied the expression of transforming growth factor receptors in a panel of human colon carcinoma cell lines and in several untransformed epithelial cell populations. The results have revealed that neoplastic colon cells express receptors for both TGF-alpha/EGF and TGF-beta. Immunoprecipitation identified the TGF-alpha/EGF receptor as a structurally intact 170-kDa protein. No evidence for over-expression was found. TGF-alpha (and EGF) enhanced receptor autophosphorylation, indicating that these receptors were biochemically functional. TGF-beta blocked DNA synthesis in non-neoplastic epithelial cells but not in tumorigenic colon populations. There was no correlation with TGF-beta receptor number or dissociation constant. However, chemical cross-linking studies revealed a TGF-beta receptor subtype of 75 kDa in 3 of the 4 colon carcinoma cells which was undetectable in normal IEC epithelial cultures, suggesting a possible association between 75-kDa receptor expression and refractoriness to growth inhibition of TGF-beta. Together, these data support the concept that locally-produced growth regulators can function in an autocrine or paracrine manner to influence the proliferation of colon carcinoma cells.  相似文献   

7.
This study examined the expression of epidermal growth factor (EGF) cell-surface receptors, the response to exogenous ligand and the autocrine production of transforming growth factor alpha (TGF-alpha) in normal and carcinoma-derived human oral keratinocytes. One of eight malignant cell lines overexpressed EGF receptors, while the remainder expressed receptor numbers similar to normal cells. Exogenous EGF stimulated incorporation of tritiated thymidine in a dose-dependent manner. In keratinocytes expressing normal numbers of EGF receptors, the cellular response to exogenous EGF correlated positively with total EGF receptor number. SCC-derived keratinocytes produced more TGF-alpha than normal cells. There was no statistical correlation between the autocrine production of TGF-alpha, EGF cell-surface receptor expression and cellular response to exogenous EGF. While the growth-stimulatory effects of exogenous TGF-alpha were inhibited by the addition of a neutralising antibody, the presence of this antibody in conditioned medium failed to produce a similar decrease in growth. The results indicate that overexpression of EGF receptors is not an invariable characteristic of human oral squamous carcinoma-derived cell lines. Further, the contribution of TGF-alpha to the growth of normal and carcinoma-derived human oral keratinocytes in vitro may be less significant than previously documented.  相似文献   

8.
Matrix metalloproteinases (MMPs) are a growing family of zinc-dependent endopeptidases that are capable of degrading various components of the extracellular matrix. These enzymes have been implicated in a variety of physiological and pathological conditions including embryogenesis and tumour invasion. The synthesis of many MMPs is thought to be regulated by growth factors, cytokines and hormones. In this study, we investigated the effects of five exogenous growth factors known to be expressed by gliomas [epidermal growth factor (EGF), basic growth factor (bFGF), transforming growth factor beta (TGF-beta1,2) and vascular endothelial growth factor (VEGF)].on MMP-2 and MMP-9 expression in an ependymoma, two grade III astrocytomas, a grade III oligoastrocytoma and a benign meningioma. Zymogram analysis revealed that the effects of the growth factors depended upon the cell lines used in the study. Growth factors generally up-regulated MMP-2 and MMP-9 expression in the gliomas but were least effective in the meningioma; the effect being most prominent with TGF-beta1 and TGF-beta2 in all the cell lines. It is hypothesized that paracrine growth factor interplay may be crucial in the regulation of MMP expression by glioma invasion of the normal brain.  相似文献   

9.
Malignant cells frequently acquire a certain independency of exogenous growth factors via the coexpression of epidermal growth factor receptor (EGFR) and epidermal growth factor (EGF)-related molecules. In the present study we investigate a possible involvement of EGF-related molecules in the growth of human lung mesothelioma. Four well-characterised cell lines are analysed for their responsiveness to exogenous EGF and transforming growth factor alpha (TGF-alpha) as well as for coexpression of EGFR and EGF/TGF-alpha. Both growth factors are able to stimulate DNA synthesis in three cell lines, although the degree of responsiveness is very variable, but neither EGF nor TGF-alpha has an effect on the cell line ZL34. In contrast, no heterogeneity is observed in the expression of EGFR, which is similarly high in all cell lines. Analysis of cell supernatants reveals that, whereas no EGF is detected, TGF-alpha is released by two cell lines. Furthermore, these two cell lines, ZL5 and ZL34, are shown to express the membrane anchored precursor pro-TGF-alpha. Thus, coexpression of EGFR and TGF-alpha is observed on two mesothelioma cell lines. The potential autocrine mitogenic role of TGF-alpha in these two cell lines was tested using neutralising antibodies against TGF-alpha and EGFR. In ZL5 cells DNA synthesis was not affected by the presence of neutralising antibodies, indicating that an external autocrine mitogenic pathway is not active in these cells. In ZL34 cells, however, the potential autocrine loop could be disrupted, as DNA synthesis was significantly reduced in the presence of neutralising antibodies. This result gives strong evidence for an autocrine role of TGF-alpha in the growth of the mesothelioma cell line ZL34.  相似文献   

10.
Expression of human epidermal growth factor (EGF) and matrix metalloproteinase-9 (MMP-9/gelatinase B) was examined immunohistochemically in 62 cases of surgically resected esophageal carcinomas, and the correlation between EGF expression and the proliferative activity of the tumors was studied by analysing the number of proliferating cell nuclear antigen (PCNA)-positive cells. Expression of EGF and MMP-9 was observed in 16 (38.1%) and 18 (42.9%) of the 42 superficial carcinomas and 8 (40%) and 14 (70%) of the 20 advanced carcinomas, respectively. The differences in the MMP-9 expression between the superficial carcinomas and the advanced carcinomas was significant (p<0.05). The synchronous expression of EGF and MMP-9 was observed in 15 (24.2%) of 62 carcinomas, i.e. 62.5% of the 24 EGF-positive tumors expressed MMP-9, but there was no statistically significant correlation between the expression of EGF and MMP-9. The relationships between EGF expression and tumor proliferative activity and prognostic factors were investigated. The PCNA grades were significantly higher in tumors with EGF-positive than those with EGF-negative expression (p<0.05) and the EGF expression showed a good correlation between the expression of MMP-9 and vascular invasion (p<0.01). The expression of MMP-9 was stronger in the advanced than the superficial carcinomas and there was a good correlation with vascular invasion (p<0.01). In a follow-up study of 55 patients, those with tumor that expressed MMP-9 or had a high PCNA grade showed a poor prognosis. Taken together, these observations suggest that both EGF and MMP-9 participate in the invasive phenotype in human esophageal carcinoma, but the expression of EGF is not directly related to the expression of MMP-9. Additional growth factors and cytokines may be involved in regulation of MMP-9 expression in this carcinoma.  相似文献   

11.
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13.
In order to ascertain autocrine growth factors in esophageal carcinomas, we analysed expression of mRNAs and proteins for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) in 6 esophageal carcinoma cell lines. Gene alterations were also examined. All of the esophageal carcinoma cell lines expressed mRNA for EGFR and TGF-alpha genes. Interestingly, EGF mRNA of about 5.0 kb was also detected in TE-1, TE-2, and TE-8 cells. Production of protein was also confirmed by binding assay and ELISA on 3 of the 6 cell lines. The cells had a relatively high number of EGFRs and produced TGF-alpha and EGF protein at the same time. Furthermore, anti-EGF (KEM-10) and anti-TGF-alpha (WA-3) monoclonal antibodies (MAbs) inhibited spontaneous uptake of tritiated thymidine (3H-TdR) by TE-1 cells which expressed EGF, TGF-alpha and EGFR mRNA and protein. These results strongly suggest that EGF and/or TGF-alpha produced by carcinoma cells function as autocrine growth factors for human esophageal carcinomas.  相似文献   

14.
Organ cultures of human skin were incubated for 8 days under growth factor-free conditions or exposed to 10 ng ml(-1) of human recombinant epidermal growth factor (EGF) during the incubation period. Normal histological features were preserved in the absence of growth factor, while epithelial cells underwent a proliferative response and invaded the underlying stroma in the presence of exogenous EGF. The same concentrations of EGF that induced stromal invasion also resulted in up-regulation of matrix metalloproteinase-9 (MMP-9; 92-kD gelatinase B) in organ culture and keratinocyte monolayer culture, and expression of MMP-1 (interstitial collagenase) in organ culture and fibroblast monolayer culture. When skin organ cultures were exposed to a potent, irreversible EGF-receptor tyrosine kinase (EGF-RTK) antagonist along with EGF, abnormal histological features were reversed, and MMP-9 production was suppressed. In contrast, EGF-RKT antagonism had only a modest inhibitory effect on MMP-1 production. Culture fluid from keratinocytes grown in monolayer culture stimulated fibroblast proliferation and MMP-1 elaboration. Treatment of fibroblasts with the same EGF-RTK antagonist inhibited keratinocyte-induced fibroblast proliferation but had only a modest inhibitory effect (approximately 20% inhibition) on MMP-1 production. In contrast, treatment of dermal fibroblasts with Interleukin-1 Receptor Antagonist had no effect on keratinocyte-induced fibroblast growth but strongly inhibited MMP-1 production (greater than 70% inhibition). These data indicate that stromal invasion by epithelial cells in EGF-treated skin is associated with events occurring in both the epidermis and dermis. The direct effect of the exogenous growth factor appears to be primarily on the epidermis. Dermal events reflect, at least in part, a response to factors elaborated in the epidermis.  相似文献   

15.
Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) has been shown to stimulate the growth of various cell types in an autocrine or paracrine manner. Although HB-EGF is widely expressed in tumors when compared with normal tissue, its contribution to cancer progression remains obscure. The objective of this study was to explore the effects of HB-EGF on proliferation, invasion activity and MMP-9 levels of an oral squamous cell carcinoma cell line, HSC3, in vitro. MTT assays, Matrigel invasion assays and RT-PCR in combination with RNA interference (RNAi) were used in this study. An RNAi-mediated decrease in HB-EGF expression reduced invasion activity and MMP-9 mRNA levels, but not proliferation, in HSC3 cells. The addition of purified HB-EGF to cell culture medium upregulated MMP-9 mRNA levels in HSC3 cells. Furthermore, the TACE inhibitor TAPI-2 or EGFR inhibitor AG1478 decreased MMP-9 mRNA levels in HSC3 cells. These data indicate that HB-EGF released from HSC3 cells by TACE stimulates EGFR in an autocrine manner, which in turn activates invasion activity via MMP-9 upregulation.  相似文献   

16.
The effect of human epidermal growth factor (hEGF) on the growthof various histological types of six human gastric carcinomacell lines was examined. The cell lines had relatively highaffinity EGF receptors (dissociation constant Kd = 10–9to 10–10 M). One gastric cancer cell line, MKN-74 (welldifferentiated adenocarcinoma) showed no response to hEGF, incell growth, DNA synthesis or 125I-hEGF cell binding. Therewere no apparent correlations between histological type andcell growth, DNA synthesis or number of EGF receptors in thesecells. The number of EGF receptors and the Kd value of the gastriccarcinoma cell lines varied with their internal and externalenvironments. hEGF concentrations corresponding to maximum stimulationin DNA synthesis varied between cell lines. The results suggestsome gastric carcinoma cells to have EGF receptors and theirgrowth seemingly to be stimulated by EGF in vitro. There are,however, no obvious correlations between the effect of hEGFon the growth of human gastric carcinoma cell lines or theirhistological type.  相似文献   

17.
The pattern of TGF-beta mRNA expression and response to TGF-beta isoforms has been examined in three lung squamous carcinoma cell lines (NX002, CX140 and CX143). Expression for TGF-beta1 and TGF-beta2 but not TGF-beta3 was found in all 3 lines. TGF-beta1 and TGF-beta3 (but not TGF-beta2) inhibited the growth of the NX002 cell line in culture. The effect of TGF-beta1 on growth was accompanied with changes in the cell cycle. These data indicate that the potential for autocrine regulation by TGF-beta is present in lung squamous carcinoma cells.  相似文献   

18.
The effects of EGF and TGF-beta 1 on the proliferation of 2 ovarian carcinoma cell lines (IGROV1 and OVCCR1) were evaluated. The cell lines were adapted to grow in a restricted serum (0.5%) medium. EGF was required for proliferation of both ovarian cell lines. Low doses of TGF-beta 1 inhibited clonogenic capacity and attenuated the EGF-mediated stimulation of DNA synthesis in OVCCR1 cells. TGF-beta 1 inhibited OVCCR1 cell proliferation by blocking the cell cycle at the G1/S transition. TGF-beta 1 did not affect either clonal or monolayer growth of IGROV1 cells. Both cell lines express type-I and type-III TGF-beta receptors, suggesting that the unresponsiveness of IGROV1 cells to TGF-beta 1 occurs at a post-receptor level. TGF-beta 1 mRNA was detected in OVCCR1 cells and in 8 out of 11 of the ovarian tumor specimens examined.  相似文献   

19.
目的:探讨CXC趋化因子受体2(CXCR-2)在食管鳞癌中的表达及其与基质金属蛋白酶9(MMP-9)、血管内皮生长因子(VEGF)表达的相关性。方法:收集河北北方学院附属第一医院胸外科2016年12月—2019年12月诊治的70例食管鳞癌患者食管癌组织及癌旁正常组织,分别采用实时荧光定量PCR法(qPCR)和免疫组化法检测CXCR-2、MMP-9、VEGF mRNA和蛋白在两组标本中的表达情况,采用Pearson相关分析法分析CXCR-2、MMP-9和VEGF表达的相关性,受试者操作特征(ROC)曲线分析CXCR-2的表达对食管鳞癌的诊断意义。结果:qPCR检测结果显示,癌组织中CXCR-2、MMP-9、VEGF mRNA的相对表达水平高于癌旁正常组织(均为P < 0.01);免疫组化检测结果显示,癌组织中CXCR-2、MMP-9、VEGF蛋白的阳性表达率高于癌旁正常组织(均为P < 0.01);且癌组织中CXCR-2的表达与MMP-9、VEGF的表达呈正相关(r分别为0.488和0.491,均为P < 0.01);癌组织中CXCR-2表达的ROC曲线下面积为0.938[95% CI (0.908,0.972),P < 0.05],最佳截断点为0.77。其诊断的灵敏度和特异度分别为91.2%和80.9%。结论:食管鳞癌组织中CXCR-2、MMP-9和VEGF呈高水平表达,且与TNM分期、淋巴结转移和远处转移关系密切,CXCR-2表达水平的检测对食管鳞癌诊断有重要价值。  相似文献   

20.
To determine the crucial abnormality in the cell cycle regulatory proteins in human squamous cell carcinoma of the esophagus, we examined the cell growth ratio (CGR) and basal expression levels of G1 cyclins (cyclin D1, cyclin E), cyclin-dependent kinase (cdk) 2, cdk4, proliferating cell nuclear antigen (PCNA), and p21Waf-1 using 9 cell lines (KE3, KE4, TE8, TE9, TE10, TE11, YES1, YES2, and YES6). Western blotting revealed an inverse linear correlation between the basal levels of p21Waf-1 expression and CGR. The protein levels of G1 cyclins, cdks, and PCNA did not coordinately reflect the CGR. There was no relationship between p21Waf-1 expression levels and mutation of the p53 gene. Next, when the cells were stimulated with serum 48 h after the starvation, stimulated levels of the above G1 cell cycle markers were variously observed among cell lines irrespective of CGR. Serum stimulation markedly induced phosphorylated Rb in TE9 (a high CGR cell line, CGR>2.0), but not in KE4 (a low CGR cell line, CGR<1.5). Furthermore, adenovirus-mediated expression of exogenous p21Waf-1 effectively reduced cell growth in KE3 and TE9 (high CGR cell lines), but not in KE4 and TE11 (low CGR cell lines). p21Waf-1-mediated growth suppression was associated with the induction of involucrin, a marker of squamous cell differentiation. Our data suggested that the basal level, but not the stimulated level, of p21Waf-1 expression play a pivotal role in abnormal growth in human squamous cell carcinoma of the esophagus.  相似文献   

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