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1.
Elevated Carcinoembryonic antigen (CEA) levels in the serum indicate a poor prognosis for colorectal cancer patients. Induction of proinflammatory cytokines by CEA interaction with Kupffer cells has been proposed as a mechanism for hepatic metastasis formation. Studies show that the cytokine response in circulating and peritoneal macrophages is regulated by beta-adrenergic receptor signals, though little information is available regarding Kupffer cells. We investigated the relationship between beta-adrenergic receptor stimulation and the response of Kupffer cells to CEA. Comparisons between unstimulated and CEA stimulated rat Kupffer cells, using cDNA arrays, showed up-regulation (>4 fold) of the beta2-adrenergic receptor mRNA. Peak up-regulation occurred after 30 min with a decline at 1 h. We examined the effects of the specific beta2-adrenergic receptor agonist terbutaline on cytokine production by CEA stimulated rat Kupffer cells. Pre-treatment of Kupffer cells with terbutaline followed by CEA caused a significant increase in IL-6 and IL-10 production, but a significant reduction in TNF-alpha production (>3 fold). mRNA levels reflected those of the ELISA assays for IL-6 and IL-10 but not for TNF-alpha. For IL-6 and TNF-alpha, these changes were serum independent, while IL-10 was serum dependent. This response is different from LPS treated Kupffer cells where all three cytokines showed serum dependency. Overall, these data suggest that Kupffer cell stimulation by CEA is under beta-adrenergic receptor control and induction of the beta-receptor is an early event following CEA binding to its receptor. Control of TNF-alpha production is negatively affected by terbutaline, while that of IL-6 and IL-10 is positively controlled suggesting that very different beta-adrenergic receptor signaling pathways are involved.  相似文献   

2.
OBJECTIVES: To analyse the behaviour of pre-surgical serum levels of soluble (s)E-selectin and vascular cell adhesion molecule (sVCAM) in patients with colorectal cancer, and to evaluate their possible correlation with carcinoembryonic antigen (CEA), pro-inflammatory cytokines and clinicopathological features with respect to their prognostic value in predicting metastatic disease. METHODS: Pre-surgical serum levels of sE-selectin, sVCAM, interleukin-6 (IL-6), IL-1beta, tumour necrosis factor-alpha (TNF-alpha) and CEA were measured in 194 patients with colorectal adenocarcinoma, 40 patients with benign colorectal diseases and 59 healthy subjects. RESULTS: sE-selectin, sVCAM, TNF-alpha and IL-6 levels were significantly higher in patients with colorectal cancer compared to either healthy subjects or patients with benign disease. Positive rates of sE-selectin, sVCAM and TNF-alpha levels were significantly associated with Dukes' stage D colorectal cancer, and all three variables were independently associated to the presence of distant metastases. Positive sE-selectin, sVCAM and TNF-alpha levels were significantly associated to CEA. TNF-alpha and CEA levels were independently related to the presence of positive levels of sE-selectin and/or sVCAM. CONCLUSIONS: Our findings suggest that the host inflammatory response to cancer cells, and/or their released products (i.e. CEA), might be responsible (via cytokine release) for the elevation in circulating adhesion molecules in patients with colorectal cancer.  相似文献   

3.
Tumor cells cause ischemia/reperfusion (I/R) injury as they arrest within the hepatic microvasculature with the production of nitric oxide (NO) and reactive oxygen species (ROS) that kill both host liver and implanting tumor cells. Carcinoembryonic antigen (CEA) both facilitates the survival of experimental metastasis to nude mouse liver by weakly metastatic human colorectal carcinomas (CRCs) and induces the release of the proinflammatory cytokine IL-6. We hypothesized that CEA also stimulates the release of the antiinflammatory cytokine IL-10 causing inhibition of the toxicity of hepatic I/R injury and indirect stimulation of tumor cell colonization of the liver. Intravenous injection of CEA produced more than 1 ng/ml of IL-10 in the systemic circulation within 1 hr which subsided by 8 hr. The IL-10 response is specific to CEA since the pentapeptide sequence in CEA that binds to the CEA receptor stimulated isolated Kupffer cells to produce IL-10. IL-10, but not IL-6, increased the survival of weakly metastatic CRC cocultured with ischemic-reoxygenated liver fragments but did not affect the survival of CRC exposed to oxidative stress in the absence of any host cells. CEA, IL-6 and IL-10 pretreatment reduced expression of iNOS but only CEA and IL-10 strongly inhibited NO and total reactive species production by ischemic-rexoygenated liver. IL-6 was toxic to CRC exposed to oxidative stress while IL-10 did not have a direct effect on CRC. Thus, CEA stimulates production of IL-10 that may enhance metastasis by promoting the ability of circulating CRC cells to survive the I/R injury of implantation.  相似文献   

4.
Autocrine secretion of cytokines by metastatic colorectal cancer cells and their role during invasion and liver homing has been poorly characterized. In this study, we used cytokine arrays to analyze the secretomes of poorly and highly metastatic colorectal cancer cells. Compared with poorly metastatic cancer cells, highly metastatic cells expressed increased levels of the immunosuppressive cytokines interleukin (IL)-4 and IL-13 in addition to increased surface expression of the high affinity IL-13 receptor IL-13Rα2, suggesting that IL-13Rα2 mediates IL-13 effects in colorectal cancer cells. Silencing of IL-13Rα2 in highly metastatic cells led to a decrease in adhesion capacity in vitro and a reduction in liver homing and increased survival in vivo, revealing a role for this receptor in cell adhesion, migration, invasion, and metastatic colonization. In support of this, IL-13 signaling activated the oncogenic signaling molecules phosphoinositide 3-kinase, AKT, and SRC in highly metastatic cells. Clinically, high expression of IL-13Rα2 was associated with later stages of disease progression and poor outcome in patients with colorectal cancer. Our findings therefore support a critical role for IL-13Rα2 expression in colon cancer invasion and metastasis.  相似文献   

5.
Migration of blood-borne lymphocytes into lymphoid tissues and sites of inflammation is initiated by vascular adhesion molecules and proinflammatory cytokines. Previous in vivo studies have shown that febrile temperatures dynamically stimulate adhesion in differentiated high endothelial venules (HEV), which are portals for lymphocyte extravasation. This report examines the direct effect of fever-range hyperthermia on the expression of adhesion molecules and cytokines by primary cultured endothelial cells. In both macrovascular (HUVEC) and microvascular (HMVEC) endothelial cells, fever-range hyperthermia (40 degrees C for 6-12 h) did not affect expression of adhesion molecules (ICAM-1, E-selectin, VCAM-1, P-selectin, PECAM-1, PNAd, MAdCAM-1), cytokine release (IL-1beta, TNF-alpha, IFN-gamma, IL-6, IL-11, IL-12, IL-13), or chemokine secretion (IL-8, RANTES, MCP-1, MIP-1beta, MIG). This is in contrast to the stimulatory effects of TNF-alpha or 43 degrees C heat shock. However, a novel role for fever-range hyperthermia was identified in augmenting actin polymerization in cultured endothelial cells and enhancing the ability of endothelial-derived factors to transactivate the alpha4beta7 integrin lymphocyte homing receptor. These findings provide insight into the tightly regulated effects of fever-range hyperthermia that exclude induction of adhesion in non-activated endothelium of normal blood vessels. Through these mechanisms, it is proposed that febrile temperatures associated with infection or clinical hyperthermia avoid the unproductive exodus of lymphocytes to non-involved extralymphoid tissues while simultaneously promoting lymphocyte delivery to sites of immune activation.  相似文献   

6.
In this experimental study, the influence of surgery-induced proinflammatory cytokines on tumor recurrence in the lung was investigated. A reproducible human in vitro assay was developed to study the adhesion of HT29 colon carcinoma cells to monolayers of microvascular endothelial cells of the lung (HMVECs-L) or human umbilical venous endothelial cells (HUVECs). Preincubation of HMVECs-L with maximally active concentrations of IL-1beta and TNF-alpha, but not with IL-6, resulted in at least 250% adhesion compared to control adhesion (p 相似文献   

7.
The cell-cell interactions between tumor cells and stromal cells are considered to be important in the regulation of tumor development at primary and metastatic secondary sites. We studied the effects of various cytokines on the cell-cell interactions between androgen-dependent LNCaP or androgen-independent PC-3 human prostate cancer cell lines and normal fibroblasts using a co-culture system. Among the tested combinations of cytokines and fibroblasts, strong modulations of cytokine actions were seen in coculture with human normal fibroblasts WI-38. While interleukin (IL)-1beta or tumor necrosis factor-alpha (TNF-alpha) partially suppressed LNCaP cell growth in monoculture, each cytokine completely inhibited it in the case of coculture with WI-38 cells. On the other hand, they did not inhibit PC-3 cell growth significantly, regardless of monoculture or coculture. Conditioned medium prepared from WI-38 cells pretreated with IL-1beta or TNF-alpha also strongly inhibited LNCaP cell growth. In the conditioned medium, marked IL-6 secretion was induced from WI-38 cells by IL-1beta or TNF-alpha. Furthermore, neutralizing antibodies to IL-6 or IL-6 receptor abrogated the antiproliferative effects of IL-1beta- and TNF-alpha-pretreated WI-38 conditioned medium. These results demonstrate that the antiproliferative effects of IL-1beta and TNF-alpha on prostate cancer cells are enhanced by coculture with normal fibroblasts through some diffusible factor(s), such as IL-6, from the stimulated fibroblasts.  相似文献   

8.
Angiogenesis is a crucial step in the growth and metastasis of cancers. The activation of endothelial cells and their further behavior are very critical during angiogenesis. The authors analyze the effect of allyl isothiocyanate (AITC) and phenyl isothiocyanate (PITC) on angiogenesis in an in vitro model using human umbilical vein endothelial cells (HUVECs). AITC and PITC significantly inhibited endothelial cell migration, invasion, and tube formation. (3)H-thymidine proliferation assay showed that AITC and PITC significantly inhibited the proliferation of HUVECs in vitro. The authors also studied the effect of AITC and PITC on the serum cytokine profiles of angiogenesis-induced animals and found that these compounds are highly potent in the downregulation of vascular endothelial growth factor (VEGF) and proinflammatory cytokines such as interleukin (IL)-1beta , IL-6, granulocyte macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-alpha). Treatment with these compounds showed an elevation in the levels of IL-2 and tissue inhibitor of metalloproteinases (TIMP)-1, which are antiangiogenic factors. Moreover, studies using B16F-10 melanoma cells showed that both AITC and PITC significantly reduced VEGF mRNA expression. These findings suggest that AITC and PITC act as angiogenesis inhibitors through the downregulation of VEGF and proinflammatory cytokines such as IL-1beta, IL-6, GM-CSF, and TNF-alpha and upregulation of IL-2 and TIMP.  相似文献   

9.
Preoperative and postoperative cytokines in patients with cancer.   总被引:33,自引:0,他引:33  
H Nakazaki 《Cancer》1992,70(3):709-713
BACKGROUND. Changes in tumor necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and granulocyte macrophage-colony-stimulating factor (GM-CSF) were investigated before and after operation in patients with hepatocellular carcinoma (HCC), metastatic liver carcinoma, and gastrointestinal carcinoma. RESULTS. Serum levels of TNF-alpha, IL-1 alpha, and IL-1 beta were high in patients with liver carcinoma (HCC and metastatic liver carcinoma) before operation in comparison with those of normal controls (P less than 0.01). In patients with gastrointestinal carcinoma, serum levels of cytokines, except those of TNF-alpha, were the same as in patients with liver carcinoma. The level of TNF-alpha in patients with gastrointestinal carcinoma was low compared with that in patients with liver carcinoma. Within 1 day after operation, the peak level of TNF-alpha was observed at 15 hours, IL-1 alpha at 18 hours, IL-1 beta at 21 hours, and IL-6 at 24 hours after operation. Subsequently, these cytokine levels peaked again: TNF-alpha at 48 hours, IL-1 alpha at 72 hours, IL-1 beta at 120 hours, and IL-6 at 168 hours after operation. GM-CSF levels increased gradually after operation. Moreover, in HCC, serum levels of TNF-alpha were high in patients with recurrence compared with those without recurrence (P less than 0.01). The difference in IL-1 alpha and IL-1 beta levels between patients with recurrence and those without recurrence can be regarded as significant (P less than 0.01). CONCLUSION. These results suggest that TNF-alpha, IL-1, IL-6, and GM-CSF may play an important role in the pathogenesis of cancers; TNF-alpha may be especially important as a tumor marker in HCC and metastatic liver carcinoma.  相似文献   

10.
Increasing evidence suggests that an intimate correlation may exist between the production of a cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF) and the ability to metastasize spontaneously in the lungs in murine transplantable tumors. In the present study, we further examined the cytokine production by tumor cells with the ability to metastasize in the liver. Four out of 8 test tumors, which produced metastasis in the lungs but not in the liver, exhibited the ability to produce GM-CSF activity in culture. Three other tumors produced metastasis in the liver but not in the lungs. These tumor cells exhibited no ability to produce GM-CSF, but two of them expressed an interleukin-6 (IL-6) mRNA and also produced IL-6 activity in the culture fluids. One of the two IL-6-producing tumors and the remaining liver metastatic tumor produced interleukin-1 (IL-1) as revealed by bioassay and neutralization test. In the tumor cells producing pulmonary metastasis, neither IL-6 gene expression nor IL-1 production could be detected. The last test tumor, which produced no metastasis either in the lungs or liver, produced neither GM-CSF, IL-1 nor IL-6. Furthermore, injection of antisera reactive to recombinant murine IL-6 caused a marked decrease of the number of liver metastases of an IL-6-producing tumor, but not lung metastases of a GM-CSF-producing tumor, which could be markedly inhibited by injection of anti-recombinant murine GM-CSF sera. These results suggest the possibility that there may be a correlation between the cytokines produced by tumor cells and their organ specificity in spontaneous metastasis, and also indicate that these tumor models may provide a useful tool for studies on the role of cytokines in tumor metastasis.  相似文献   

11.
Increasing evidence suggests that an intimate correlation may exist between the production of a cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF) and the ability to metastasize spontaneously in the lungs in murine transplantable tumors. In the present study, we further examined the cytokine production by tumor cells with the ability to metastasize in the liver. Four out of 8 test tumors, which produced metastasis in the lungs but not in the liver, exhibited the ability to produce GM-CSF activity in culture. Three other tumors produced metastasis in the liver but not in the lungs. These tumor cells exhibited no ability to produce GM-CSF, but two of them expressed an interleukin-6 (IL-6) mRNA and also produced IL-6 activity in the culture fluids. One of the two IL-6-producing tumors and the remaining liver metastatic tumor produced interleukin-1 (IL-1) as revealed by bioassay and neutralization test. In the tumor cells producing pulmonary metastasis, neither IL-6 gene expression nor IL-1 production could be detected. The last test tumor, which produced no metastasis either in the lungs or liver, produced neither GM-CSF, IL-1 nor IL-6. Furthermore, injection of antisera reactive to recombinant murine IL-6 caused a marked decrease of the number of liver metastases of an IL-6-producing tumor, but not lung metastases of a GM-CSF-producing tumor, which could be markedly inhibited by injection of anti-recombinant murine GM-CSF sera. These results suggest the possibility that there may be a correlation between the cytokines produced by tumor cells and their organ specificity in spontaneous metastasis, and also indicate that these tumor models may provide a useful tool for studies on the role of cytokines in tumor metastasis.  相似文献   

12.
Several studies have demonstrated a decreased cytokine production in patients with cancer. Likewise, there is some evidence showing that tumor markers may play a role in immunoregulation. In this work, we have studied the in vitro production of IL-1beta, IL-6 and TNF-alpha in whole-blood cell cultures of 10 healthy subjects after polyclonal activation with lipopolysaccharide of Salmonella enteridis and phytohemagglutinin in the presence or absence of three markers, AFP, CEA and PSA. Each sample was incubated for 48 h at 37 degrees C in a humidified atmosphere of 5% CO(2). Subsequently, cytokine levels in the supernatant were determined. AFP did not significantly affect the production of the three cytokines compared to the basal value obtained on adding PBS. In contrast, CEA significantly increased the production of IL-6 (p <0.001) and TNF-alpha (p = 0.002), while PSA significantly decreased IL-1beta (p <0.001), IL-6 (p = 0.031) and TNF-alpha (p <0.0001) production. These results suggest a possible role of CEA and PSA in the production of these cytokines.  相似文献   

13.
We examined whether interleukin-1 (IL-1), a multifunctional proinflammatory cytokine, progresses or regresses metastasis of lung cancer. Exogenous IL-lβ enhanced expression of various cytokines (IL-6, IL-8, and vascular endothelial growth factor (VEGF)) and intracellular adhesion molecule-1 (ICAM-1) by A549, PC14, RERF-LC-AI, and SBC-3 cells expressing IL-1 receptors. A549 cells transduced with human IL-1β -gene with the growth-hormone signaling-peptide sequence (A549/IL-1β) secreted a large amount of IL-1β protein. Overexpression of IL-1β resulted in augmentation of expression of the cytokines, ICAM-1, and matrix metallo-proteinase-2 (MMP-2). A549/IL-1β cells intravenously inoculated into severe combined immunodeficiency (SCID) mice distributed to the lung more efficiently and developed lung metastasis much more rapidly than did control A549 cells. Treatment of SCID mice with anti-IL-1β antibody inhibited formation of lung metastasis by A549/IL-1β cells. Moreover, A549/IL-1β cells inoculated in the subcutis grew more rapidly, without necrosis, than did control A549 cells, which produced smaller tumors with central necrosis, suggesting involvement of angiogenesis in addition to enhanced binding in the high metastatic potential of A549/IL-1β cells. Histological analyses showed that more host-cell infiltration, fewer apoptotic cells, more vascularization, and higher MMP activity were observed in tumors derived from A549/IL-1β cells, compared with tumors derived from control A549 cells. These findings suggest that IL-1β facilitates metastasis of lung cancer via promoting multiple events, including adhesion, invasion and angiogenesis. (Cancer Sci 2003; 94: 244–252)  相似文献   

14.
Cellular adhesion molecules of the cadherin, integrin, and immunoglobulin superfamilies are important to both growth and metastasis of many cancers, including malignant melanoma. Malignant melanoma is an excellent model for studying these molecules, due in part to a sequential series of five defineable stages. As the malignant phenotype of melanoma cells changes from the noninvasive radial growth phase to the vertical growth phase, which has high metastatic potential, so does the repertoire of the cellular adhesion molecules expressed on the cells surface. The cellular adhesion molecule MCAM/MUC18 confers metastatic potential and increased tumorigenicity to melanoma cells. MCAM/MUC18 mediates homotypic and heterotypic adhesion between melanoma cells and endothelial cells, respectively. Both types of interaction may promote metastasis at different stages in the metastasis cascade. We developed a fully humanized antibody to MCAM/MUC18 (ABX-MA1) that blocked melanoma metastasis in vivo. Furthermore, ABX-MA1 blocked the homotypic interaction between melanoma cells and endothelial cells as well as the promoter and collagenase activity of MMP-2. During melanoma progression the loss of E-cadherin expression disrupts normal homeostasis in the skin by freeing melanoma cells from structural and functional regulation by keratinocytes. The loss of functional E-cadherin is parallelled by a gain in N-cadherin function that mediates homotypic interaction between melanoma cells, facilitates gap-junctional formation with fibroblasts and endothelial cells and promotes melanoma cell migration and survival. In addition, loss of E-cadherin may affect the beta-catenin/wnt signaling pathways, resulting in deregulation of genes involved in growth and metastasis. The integrin family member alpha(v)beta(3) is widely expressed on melanoma cells in the vertical growth phase. When alpha(v)beta(3) is expressed in melanoma cells in the radial growth phase, this integrin is associated with increased tumor growth in vivo. alpha(v)beta(3) may also promote melanoma invasion, through an interaction with MMP-2, and transendothelial migration, via a heterotypic melanomaendothelial cell interaction. This review summarizes recent knowledge on how changes in these adhesion molecules contribute to the acquisition of the metastatic phenotype in human melanoma.  相似文献   

15.
16.
Carcinoembryonic antigen (CEA) is an oncofetal antigen whose function in the progression of colorectal carcinoma remains unclear although recent studies suggest it participates in homotypic cellular adhesion. We have previously shown that 40 micrograms of CEA injected intravenously into athymic nude mice enhances experimental metastasis in liver and lung by two human colorectal carcinoma cell lines that are injected intrasplenically 30 min later. The metastatic potential of another three moderately to highly metastatic colorectal carcinoma cell lines and of one weakly metastatic line has now been analysed in this model. CEA pretreatment only enhanced colony formation by cell lines that were weakly metastatic in untreated nude mice; it did not affect experimental metastasis by highly metastatic lines. CEA pretreatment enhanced the retention of 125I Idudr-labelled weakly metastatic tumour cells within the liver and lungs 4 h after intrasplenic injection but not the retention of highly metastatic tumour cells or inert latex beads. A significant correlation existed between the formation of experimental metastases and the early retention of tumour cells within the liver after intrasplenic injection. Aggregation did not appear to be important for retention in liver because CEA did not aggregate colorectal carcinoma cells in vitro. Also CEA did not alter natural host effector cell function in a cytolysis assay in vitro. We suggest that CEA facilitates liver colonisation by three of eight human colorectal carcinomas in athymic nude mice by increasing the hepatic retention of tumour cells. The potential mechanisms by which CEA may increase the retention of tumour cells in the liver are discussed.  相似文献   

17.
18.
We investigated effects of endostatin (ES) in the prometastatic microenvironment of inflammation occurring during the microvascular phase of cancer cell infiltration in the liver. We used a model of intrasplenic injection of B16 melanoma (B16M) cells leading to hepatic metastasis through vascular cell adhesion molecule-(VCAM-1)-mediated capillary arrest of cancer cells via interleukin-18 (IL-18)-dependent mechanism. We show that administration of 50 mg/kg recombinant human (rh) ES 30 min before B16M, plus repetition of same dose for 3 additional days decreased metastasis number by 60%. A single dose of rhES before B16M injection reduced hepatic microvascular retention of luciferase-transfected B16M by 40% and inhibited hepatic production of tumor necrosis factor alpha (TNF-alpha) and IL-18 and VCAM-1 expression by hepatic sinusoidal endothelia (HSE). Consistent with these data, rhES inhibited VCAM-1-dependent B16M cell adhesion to primary cultured HSE receiving B16M conditioned medium, and it abolished the HSE cell production of TNF-alpha and IL-18 induced by tumor-derived vascular endothelial cell growth factor (VEGF). rhES abrogated recombinant murine VEGF-induced tyrosine phosphorylation of KDR/flk-1 receptor in HSE cells, preventing the proinflammatory action of tumor-derived VEGF on HSE. rhES also abolished hepatic production of TNF-alpha, microvascular retention of luciferase-transfected B16M, and adhesion of B16M cells to isolated HSE cells, all of them induced in mice given 5 micro g/kg recombinant murine VEGF for 18 h. This capillary inflammation-deactivating capability constitutes a nonantiangiogenic antitumoral action of endostatin that decreases cancer cell arrest within liver microvasculature and prevents metastases promoted by proinflammatory cytokines induced by VEGF.  相似文献   

19.
Constitutive expression of the inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) is characteristic of malignant ovarian surface epithelium. We investigated the hypothesis that this autocrine action of TNF-alpha generates and sustains a network of other mediators that promote peritoneal cancer growth and spread. When compared with two ovarian cancer cell lines that did not make TNF-alpha, constitutive production of TNF-alpha was associated with greater release of the chemokines CCL2 and CXCL12, the cytokines interleukin-6 (IL-6) and macrophage migration-inhibitory factor (MIF), and the angiogenic factor vascular endothelial growth factor (VEGF). TNF-alpha production was associated also with increased peritoneal dissemination when the ovarian cancer cells were xenografted. We next used RNA interference to generate stable knockdown of TNF-alpha in ovarian cancer cells. Production of CCL2, CXCL12, VEGF, IL-6, and MIF was decreased significantly in these cells compared with wild-type or mock-transfected cells, but in vitro growth rates were unaltered. Tumor growth and dissemination in vivo were significantly reduced when stable knockdown of TNF-alpha was achieved. Tumors derived from TNF-alpha knockdown cells were noninvasive and well circumscribed and showed high levels of apoptosis, even in the smallest deposits. This was reflected in reduced vascularization of TNF-alpha knockdown tumors. Furthermore, culture supernatants from such cells failed to stimulate endothelial cell growth in vitro. We conclude that autocrine production of TNF-alpha by ovarian cancer cells stimulates a constitutive network of other cytokines, angiogenic factors, and chemokines that may act in an autocrine/paracrine manner to promote colonization of the peritoneum and neovascularization of developing tumor deposits.  相似文献   

20.
Murine RAW117 large-cell lymphoma cells that show organ preferences of metastatic colonization were selected. We examined the role of adhesive systems in determining the organ preference of metastasis using cell lines of low (RAW117-P) and high (RAW117-H10) liver-metastatic potential. Highly metastatic H10 cells adhered at higher rates than low metastatic P cells to target organ microvessel endothelial cells, and these interactions were partially inhibited by RGD-containing polymers but not by small peptides such as GRGDS or GRGES. The most effective polymers, such as (GRGDS)4 and GRGDS(GRGES)2GRGDS, significantly inhibited H10 cell adhesion but had less effect on P cell adhesion to target liver sinusoidal endothelial cell monolayers or on P cell or H10 cell adhesion to bovine aortic endothelial cell monolayers. The (GRGDS)4 polymer reduced the rate of H10 liver sinusoidal endothelial cell adhesion to that of P cells in the absence of inhibitors, suggesting that the quantitative difference in adhesion of H10 cells versus P cells to liver sinusoidal endothelial cells may have been due to integrin-like molecules. Other RGD-containing polymers, such as (GRGES)2(GRGDS)2, GRGES(GRGDS)2GRGES, or (GRGES)4, were less effective, suggesting that the secondary structure of the polymers may be an important consideration. A peptide from the B1 chain of laminin (YIGSR) or its homopolymer, (YIGSR)4, had no effect on endothelial cell adhesion, consistent with the lack of differential laminin adhesion seen with various RAW117 cell lines. The results suggest that integrin-related molecules may play a role in the organ specificity of endothelial cell adhesion seen with RAW117 tumor cells.  相似文献   

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