Tumor necrosis factor-alpha-converting enzyme activities and tumor-associated macrophages in breast cancer

The role of the tumor microenvironment especially of tumor-associated macrophages (TAMs) in the progression and metastatic spread of breast cancer is well established. TAMs have primarily a M2 (wound-healing) phenotype with minimal cytotoxic activities. The mechanisms by which tumor cells influence TAMs to display a pro-tumor phenotype are still debated although the key roles of immunomodulatory cytokines released by tumor cells, including colony-stimulating factor 1, tumor necrosis factor (TNF) and soluble TNF receptors 1/2, soluble vascular cell adhesion molecule 1, soluble interleukin 6 receptor and amphiregulin, have been demonstrated. Importantly, these factors are released through ectodomain shedding by the activities of the tumor necrosis factor-alpha-converting enzyme (TACE/ADAM17). The role of TACE activation leading to autocrine effects on tumor progression has been extensively studied. In contrast, limited information is available on the role of tumor cell TACE activities on TAMs in breast cancer. TACE inhibitors, currently in clinical trials, will certainly affect TAMs and subsequently treatment outcomes based on the substrates it releases. Furthermore, whether targeting a subset of the molecules shed by TACE, specifically those leading to TAMs with altered functions and phenotype, holds greater therapeutic promises than past clinical trials of TACE antagonists’ remains to be determined. Here, the potential roles of TACE ectodomain shedding in the breast tumor microenvironment are reviewed with a focus on the release of tumor-derived immunomodulatory factors shed by TACE that directs TAM phenotypes and functions.     

川崎病肿瘤坏死因子α变化的研究

目的探讨肿瘤坏死因子α在川崎病（Kawasaki disease，KD）发生发展中的作用。方法对我院2003年1月～2005年10月住院的39例KD患者分别于急性期（疾病的1～11天）和恢复期（疾病21天）取血，用ELISA方法测定肿瘤坏死因子α。结果1，KD患儿急性期肿瘤坏死因子α升高；2.疾病恢复期肿瘤坏死因子α降低；3．急性期。肿瘤坏死因子α增高与末梢血白细胞总数呈明显正相关（rTNF-α=0．875）。结论TNF-α等细胞因子参与KD的病理过程，细胞因子的级联放大效应是非特异性血管炎性损伤的基础；川崎病急性期存在T淋巴细胞调控网络失衡。     

Cytokines and cancer: experimental systems.

The transfer of certain cytokine genes into cancer cells can provide very powerful suppression of tumor growth in the absence of any toxic side effects. Some of these cytokines, such as interleukin-4, granulocyte colony-stimulating factor and tumor necrosis factor, can mediate powerful immune suppression even in T-cell-deficient animals and appear to be effective for poorly or non-antigenic tumors. However, approaches must be found to induce or deliver cytokines locally at the tumor site.     

Serum values of proinflammatory cytokines are inversely correlated with serum leptin levels in patients with advanced stage cancer at different sites

Leptin is a recently identified hormone produced by the adipocyte ob gene which acts as a negative feedback signal critical to the normal control of food intake and body weight. A number of proinflammatory cytokines, such as interleukin 6, tumor necrosis factor alpha, and interferon gamma, have been proposed as mediators of cancer cachexia; these data suggest that abnormalities in leptin production/release or in its feedback mechanism play a role in cancer patients. We therefore studied the relationship between serum leptin and serum cytokines interleukin 6 and tumor necrosis factor alpha levels in advanced-stage cancer patients. Twenty-nine advanced stage cancer patients (all but one stage IV) with tumors at various sites were included in the study. A direct correlation between body mass index and serum leptin levels was found both in cancer patients and in healthy individuals. The serum levels of interleukin 6 were significantly higher in cancer patients than in healthy individuals. In cancer patients an inverse correlation was found between serum levels of leptin and proinflammatory cytokines. There was an inverse correlation between the Eastern Cooperative Oncology Group performance status scale and serum levels of leptin. Regarding survival, patients with very high serum levels of proinflammatory cytokines and very low levels of leptin had very short survival. Although obtained in a cancer patient population not overtly cachectic, our results provide further evidence that a simple dysregulation of leptin production and/or release cannot be involved in cancer-associated pathophysiological changes leading to cachexia.     

Ocular allergic disease

PURPOSE OF REVIEW: This review will focus on recent advances in our understanding of the pathogenesis of allergic eye diseases. Common findings in acute allergic conjunctivitis (seasonal and perennial) and chronic allergic conjunctivitis (vernal keratoconjunctivitis, atopic keratoconjunctivitis, and giant papillary conjunctivitis) include evidence of mast cell activation and eosinophil attraction and activation. Cytokine levels found in tears, conjunctival impression cytology and biopsy specimens, and serum have been evaluated as markers of disease, and as targets of therapeutic intervention. RECENT FINDINGS: Human conjunctival epithelial cells respond to tumor necrosis factor alpha, interleukin-1 beta, and interferon-gamma individually and in combination. Intracellular adhesion molecule-1 expression is upregulated by interleukin-1 beta and tumor necrosis factor alpha. Conjunctival epithelial cells release interleukin-8 in response to interleukin-1 beta and tumor necrosis factor alpha but not interferon-gamma. Supernatants from activated mast cells cause increased adhesion of eosinophils to conjunctival epithelium. Tear levels of tumor necrosis factor alpha were elevated in vernal keratoconjunctivitis patients compared with normal controls. T cell lines from chronic allergic eye disease patients showed inconsistent production of cytokines in atopic and vernal keratoconjunctivitis and low levels in giant papillary conjunctivitis. Vernal keratoconjunctivitis patients have differing levels of eosinophil cationic protein in their serum if they were serum specific immunoglobulin E positive compared to serum specific immunoglobulin E negative patients. SUMMARY: Recent findings continue to expand our basic knowledge of mechanisms and differences between seasonal and perennial allergic conjunctivitis and atopic and vernal keratoconjunctivitis. Understanding the complex interactions and cross talk between cells, cytokines and other mediators is relevant for new therapeutic approaches directed at specific disease entities.     

Tumor necrosis factors alpha and beta in acquired immunodeficiency syndrome (AIDS) and aids-related complex

Human immunodeficiency virus (HIV) infection is associated with abnormalities of both T-cell and B-cell immunity in patients with acquired immunodeficiency syndrome (AIDS). Previous studies demonstrated deficient production of the cytokines interleukin-1 (IL-1), interleukin-2 (IL-2), and gamma interferon (IFN-). Tumor necrosis factor alpha and tumor necrosis factor beta have not been previously investigated in AIDS. In this study we demonstrate that peripheral blood mononuclear cells from patients with HIV infection who have either AIDS-related complex or acquired immunodeficiency syndrome are deficient in the production of tumor necrosis factor alpha and tumor necrosis factor beta. These cytokines, derived predominantly from monocytes or lymphocytes, respectively, function as immunoregulatory, antitumor, and antiinfective proteins. A deficiency in their production may therefore be responsible for many of the complications associated with HIV infection in patients with AIDS-related complex or acquired immunodeficiency syndrome.     

Activation of the NF-kB pathway downregulates TFF-1 in gastric carcinogenesis

Trefoil factor 1 (TFF1) is expressed in the normal superficial epithelium of the stomach and is implicated in the maintenance of gastric epithelial structure and function. During gastric carcinogenesis, in which pro-inflammatory cytokines play a crucial role, its expression level decreases suggesting a role as tumor suppressor factor. We have compared expression of TFF1 in gastric mucosa from cancer patients, in which several degrees of inflammatory infiltrate are present, with that in normal mucosa from non-cancer patients without infiltrating inflammatory cells. TFF1 is less expressed in the superficial gastric epithelium from cancer patients than in that from normal individuals in which the nuclear factor (NF)-κB pathway is not activated. We analyzed TFF1 expression in ex vivo samples of gastric mucosa from cancer patients, and in MKN45 gastric cancer cell line after exposure to proinflammatory cytokines interleukin (IL)-1β or tumor necrosis factor (TNF)-α, that activate the NF-κB pathway. We found that IL-1β and TNF-α activate the NF-κB pathway, as reflected in the nuclear expression of p65 and the activation of p-IκBα, and downregulate TFF1 expression after 1 or 2 h of exposure. Moreover, cells in the superficial gastric epithelium in ex vivo samples co-expressed TFF1/p65 at cellular level, whereas tumor cells did not. In summary, downregulation of TFF1 expression during gastric neoplastic transformation is associated with activation of the NF-κB pathway through IL-1β or TNF-α, but other regulatory mechanisms might also be involved.     

The Role of Cytokines in Hemolytic Transfusion Reactions

Experimental evidence is accumulating to support a central role for cytokines in the pathophysiology of hemolytic transfusion reactions. The production of tumor necrosis factor, interleukin-8, and monocyte chemoattractant protein occurs in whole blood in response to ABO incompatible red cells, a model of acute hemolytic transfusion reactions. Peripheral blood mononuclear cells may produce interleukin-1β, tumor necrosis factor, interleukin-8, monocyte chemoattractant protein, and interleukin-1 receptor antagonist in response to IgG-coated red cells, a model of delayed hemolytic transfusion reactions. Cultured umbilical vein endothelial cells respond to conditioned plasma from ABO-incompatibility reactions by expressing the procoagulant tissue factor and the leukocyte adhesion molecules ELAM-1 and ICAM-1. These in vitro endothelial cell responses can be inhibited by neutralizing antibodies to tumor necrosis factor, suggesting that TNF may have a central role in intravascular coagulation and end-organ injury that may occur in acute hemolytic transfusion reactions.     

IL－6和TNF对白血病细胞的调控作用及意义

通过诱导急性白血病肿瘤细胞自分泌白细胞介素６和肿瘤坏死因子，利用急性白血病原代肿瘤细胞和肿瘤细胞系ＨＬ－６０和Ｋ５６２，分别观察了ＩＬ－６和ＴＮＦα对急性白血病细胞的调控作用。结果发现，急性白血病细胞存在着ＩＬ－６和ＴＮＦα的自分泌作用，而ＴＮＦα和ＩＬ－６对白血病细胞则有诱导分化作用；进一步研究发现，ＴＮＦα对急性白血病细胞株还可呈现生长抑制作用；而ＩＬ－６则可表现为生长促进作用。ＩＬ－６和ＴＮＦα对急性白血病细胞的这种凋控在白血病的发病和免疫调控治疗中将有意义。     

IL－6和TNF对白血病细胞的调控作用及意义

通过诱导急性白血病肿瘤细胞自分泌白细胞介素６和肿瘤坏死因子，利用急性白血病原代肿瘤细胞和肿瘤细胞系ＨＬ－６０和Ｋ５６２，分别观察了ＩＬ－６和ＴＮＦα对急性白血病细胞的调控作用。结果发现，急性白血病细胞存在着ＩＬ－６和ＴＮＦα的自分泌作用，而ＴＮＦα和ＩＬ－６对白血病细胞则有诱导分化作用；进一步研究发现，ＴＮＦα对急性白血病细胞株还可呈现生长抑制作用；而ＩＬ－６则可表现为生长促进作用。ＩＬ－６和ＴＮＦα对急性白血病细胞的这种凋控在白血病的发病和免疫调控治疗中将有意义。