TNF-alpha regulates epithelial expression of MMP-9 and integrin alphavbeta6 during tumour promotion. A role for TNF-alpha in keratinocyte migration?

ATP-dependent chromatin remodeller brahma related gene 1 promotes keratinocyte migration and modulates cell Signalling during wound healing in human skin

Skin wound healing is driven by proliferation, migration and differentiation of several cell types that are controlled by the alterations in the gene expression programmes. Brahma Gene 1 (BRG1) (also known as SMARCA4) is a core ATPase in the BRG1 Associated Factors (BAF) ATP-dependent chromatin remodelling complexes that alter DNA-histone interaction in chromatin at the specific gene regulatory elements resulting in increase or decrease of the target gene transcription. Using siRNA mediated suppression of BRG1 during wound healing in a human ex vivo and in vitro (scratch assay) models, we demonstrated that BRG1 is essential for efficient skin wound healing by promoting epidermal keratinocytes migration, but not their proliferation or survival. BRG1 controls changes in the expression of genes associated with gene transcription, response to wounding, cell migration and cell signalling. Altogether, our data revealed that BRG1 play positive role in skin repair by promoting keratinocyte migration and impacting the genes expression programmes associated with cell migration and cellular signalling.

Ultraviolet Radiation and Chronic Inflammation-Molecules and Mechanisms Involved in Skin Carcinogenesis: A Narrative Review

The process of skin carcinogenesis is still not fully understood. Both experimental and epidemiological evidence indicate that chronic inflammation is one of the hallmarks of microenvironmental-agent-mediated skin cancers and contributes to its development. Maintaining an inflammatory microenvironment is a condition leading to tumor formation. Multiple studies focus on the molecular pathways activating tumorigenesis by inflammation and indicate several biomarkers and factors that can improve diagnostic and prognostic processes in oncology and dermatology. Reactive oxygen species produced by ultraviolet radiation, oxidizers, or metabolic processes can damage cells and initiate pro-inflammatory cascades. Considering the potential role of inflammation in cancer development and metastasis, the identification of early mechanisms involved in carcinogenesis is crucial for clinical practice and scientific research. Moreover, it could lead to the progress of advanced skin cancer therapies. We focus on a comprehensive analysis of available evidence and on understanding how chronic inflammation and ultraviolet radiation can result in skin carcinogenesis. We present the inflammatory environment as complex molecular networks triggering tumorigenesis and constituting therapeutic targets.

A novel mechanism in wound healing: Laminin 332 drives MMP9/14 activity by recruiting syndecan-1 and CD44

Re-epithelialization describes the resurfacing of a skin wound with new epithelium. In response to various stimuli including that of growth factors, cytokines and extracellular matrix (ECM), wound edge epidermal keratinocytes undergo cytoskeleton rearrangements compatible with their motile behavior and develop protrusive adhesion contacts. Matrix metalloproteinases (MMP) expression is crucial for proper cell movement and ECM remodeling; however, their deposition mechanism is unknown in keratinocytes. Here, we show that similar to cytokine IL-1ß, the precursor laminin 332 pro-migratory fragment G45 induces expression of the MMP-9 pro-enzyme, which together with MMP-14, further exerts its proteolytic activity within epithelial podosomes. This event strictly depends on the expression of the proteoglycan receptor syndecan-1 that was found in a ring surrounding the podosome core, co-localised with CD44. Our findings uncover that by directly recruiting both syndecan-1 and CD44, the laminin-332 G45 domain plays a major role in regulating mechanisms underlying keratinocyte / ECM remodeling during wound repair.

Pivotal Involvement of the CX3CL1-CX3CR1 Axis for the Recruitment of M2 Tumor-Associated Macrophages in Skin Carcinogenesis

We previously revealed the crucial roles of a chemokine, CX3CL1, and its receptor, CX3CR1, in skin wound healing. Although repeated wounds frequently develop into skin cancer, the roles of CX3CL1 in skin carcinogenesis remain elusive. Here, we proved that CX3CL1 protein expression and CX3CR1⁺ macrophages were observed in human skin cancer tissues. Similarly, we observed the enhancement of CX3CL1 expression and the abundant accumulation of CX3CR1⁺ tumor-associated macrophages with M2-like phenotypes in the skin carcinogenesis process induced by the combined treatment with 7,12-dimethylbenz[a]anthracene and 12-O-tetradecanoylphorbol-13-acetate. In this mouse skin carcinogenesis process, CX3CR1⁺ tumor-associated macrophages exhibited M2-like phenotypes with the expression of Wnt3a and angiogenic molecules including VEGF and matrix metalloproteinase 9. Compared with wild-type mice, CX3CR1-deficient mice showed fewer numbers of skin tumors with a lower incidence. Concomitantly, M2-macrophage numbers and neovascularization were reduced with the depressed expression of angiogenic factors and Wnt3a. Thus, the CX3CL1-CX3CR1 axis can crucially contribute to skin carcinogenesis by regulating the accumulation and functions of tumor-associated macrophages. Thus, this axis can be a good target for preventing and/or treating skin cancers.

Immunoexpression of metalloproteinases 9 (MMP-9) and 2 (MMP-2) and their inhibitors (TIMP-1 and TIMP-2) in normal and neoplastic canine mammary tissue

Abstract The aim of this study was to perform the immunostaining of MMP-9 and MMP-2 and its inhibitors, TIMP-1 and TIMP-2, on normal and neoplastic canine mammary tissue in order to evaluate the behavior of these proteins in extracellular matrix (ECM) remodeling in different neoplastic mammary types. Thus, 48 samples of canine mammary tissue were analyzed, 14 of which complex carcinomas, 13 tubulopapillary carcinomas, six single adenomas and 15 normal mammary tissue. There were differences in MMP-9, TIMP-1 and TIMP-2 according to mammary histomorphology, and MMP-9 presented increased immunoexpression in epithelial and stromal cells in tubulopapillary and complex carcinomas. TIMP-1 exhibited reduced immunostaining in the stromal cells of the complex carcinomas and TIMP-2 enhanced immunostaining in the epithelial cells of tubulopapillary carcinomas. There was a positive correlation between MMP-9 and TIMP-1 in epithelial and stromal cells regarding immunostaining intensity and number of labeled cells in the normal breast. There was a positive correlation between MMP-9 and TIMP-2 in the epithelial cells of tubulopapillary carcinomas. It is concluded that balanced activity between MMP-9, MMP-2, TIMP-1 and TIMP-2 maintains normal canine mammary tissue homeostasis while increased immunoexpression of MMP-9 and TIMP-2 and reduced TIMP- 1 in carcinomas suggest a favorable condition for tumor evolution.

Translocating a High-Affinity Designer TIMP-1 to the Cell Membrane for Total Renal Carcinoma Inhibition: Putting the Prion Protein to Good Use

Membrane type 1-matrix metalloproteinase (MT1-MMP) and tumor necrosis factor α (TNF-α)-converting enzyme (TACE) are prominent membrane-anchored metalloproteinases that regulate the turnover of extracellular matrix (ECM) components and bioactive molecules required for cancer proliferation. In this study, we describe a novel approach that would allow tissue inhibitor of metalloproteinase 1 (TIMP-1), the endogenous inhibitor of the matrix metalloproteinases (MMPs), to be translocated to the cell membrane for simultaneous MT1-MMP/TACE inhibition. We achieve this by fusing T1^TACE, a designer TIMP-1 with superb affinities for MT1-MMP and TACE, to the glycosyl-phosphatidyl inositol anchor of prions to create a membrane-tethered, broad-spectrum inhibitor, named T1^{Pr αTACE}, that colocalizes with MT1-MMP and TACE on the cell surface. Transduction of T1^{Pr αTACE} in human fibrosarcoma cells results not only in a substantial reduction in gelatinolytic and TNF-α/heparin binding epithelial growth factor shedding activities but also in a loss of tubulogenic capability in three-dimensional matrices. In renal carcinoma, T1^{Pr αTACE} triggers cellular senescence and disrupts MMP-mediated proteolysis of ECM components such as fibronectin and collagen I, leading to an impairment in cell motility and survival under both in vitro and in vivo conditions. Taken together, our findings may provide a new perspective in TIMP targeting that could be exploited to halt metastatic renal carcinoma progression.

LRG1 Promotes Keratinocyte Migration and Wound Repair through Regulation of HIF-1α Stability

Re-epithelialization is a complex process during skin wound healing, and cell migration is an integral part of this phenomenon. Here we identified a role for LRG1 as a key regulator of epidermal keratinocyte migration where LRG1 acts via enhancement of HIF-1α stability. We showed that LRG1 is upregulated at murine skin wound edges and that addition of recombinant human LRG1 accelerates keratinocyte migration and skin wound healing. Furthermore, we identified transcription factor ELK3 as a downstream effector of LRG1. We confirmed that elevated ELK3 levels manipulated by LRG1 can promote cell migration through upregulation of HIF-1α stability. Because hyperglycemia complicatedly affects HIF-1α stability and activation, our findings provide insights into the molecular controls of wound-associated cell migration and identify potential therapeutic targets for the treatment of chronic diabetic wounds. In conclusion, we demonstrated that LRG1 promotes wound repair through keratinocyte migration and is important for normalization of an abnormal process of diabetic wound healing where HIF-1α stability is insufficient.

RNAI-MEDIATED SILENCING OF MATRIX METALLOPROTEINASE 1 IN EPIDERMAL KERATINOCYTES INFLUENCES THE BIOLOGICAL EFFECTS OF INTERLEUKIN 17A

Matrix metalloproteinases (MMPs) are important for the pathogenesis of psoriasis and other autoimmune disorders. In the extracellular matrix, accumulation of proinflammatory cytokines, such as interleukin 17A (IL-17A), leads to induction of several MMPs, including MMP1. MMPs change the composition and other properties of the extracellular matrix. These changes facilitate tissue remodeling and promote the development of psoriatic plaques. The aim of this study was to explore how MMP1 silencing might influence the biological effects of IL-17A on migration and proliferation of human epidermal keratinocytes and the expression of genes involved in their division and differentiation. The experiments were performed with MMP1-deficient and control epidermal keratinocytes, HaCaT-MMP1 and HaCaT-KTR, respectively. Cell proliferation and migration were assessed by comparative analysis of the growth curves and scratch assay, respectively. To quantify cell migration, representative areas of cell cultures were photographed at the indicated time points and compared to each other. Changes in gene expression were analyzed by real-time PCR. The obtained results demonstrated that MMP1 silencing in the cells treated with IL-17A resulted in downregulation of MMP9 and -12, FOSL1, CCNA2, IVL, KRT14 and -17 as well as upregulation of MMP2, CCND1 and LOR. Moreover, MMP1 silencing led to a decrease in cell proliferation and an impairment of cell migration. Thus, MMP1-deficiency in epidermal keratinocytes can be beneficial for psoriasis patients that experience an accumulation of IL-17 in lesional skin. Knocking MMP1 down could influence migration and proliferation of epidermal keratinocytes in vivo, as well as help to control the expression of MMP1, -2, -9 и -12, CCNA2, CCND1, KRT14 and -17 that are crucial for the pathogenesis of psoriasis.

Integrin αvβ6 and matrix metalloproteinase 9 correlate with survival in gastric cancer

AIM: To investigate the expression of integrin αvβ6 and matrix metalloproteinase 9 (MMP-9), their association with prognostic factors and to assess their predictive role in gastric cancer patients.

METHODS: Immunohistochemistry was used to determine the expressions of integrin αvβ6 and MMP-9 in 126 specimens from patients with primary gastric carcinoma. Associations between immunohistochemical staining and various clinic pathologic variables of tissue specimens were evaluated by the χ² test and Fisher’s exact test. Expression correlation of αvβ6 and MMP-9 was assessed using bivariate correlation analysis. The patients were followed-up every 3 mo in the first two years and at least every 6 mo afterwards, with a median follow-up of 56 mo (ranging from 2 mo to 94 mo). Four different combinations of αvβ6 and MMP-9 levels (that is, both markers positive, both markers negative, αvβ6 positive with MMP-9 negative, and αvβ6 negative with MMP-9 positive) were evaluated for their relative effect on survival. The difference in survival curves was evaluated with a log-rank test. Survival analysis was conducted using the Kaplan-Meier survival and Cox proportional hazards model analysis.

RESULTS: The expressions of integrin αvβ6 and MMP-9 were investigated in 126 cases, among which 34.92% were positive for αvβ6 expression, and 42.06% for MMP-9 expression. The expression of αvβ6 was associated with Lauren type, differentiation, N stage, and TNM stage (the P values were 0.006, 0.038, 0.016, and 0.002, respectively). While MMP-9 expression was associated with differentiation, T stage, N stage, and TNM stage (the P values were 0.039, 0.014, 0.033, and 0.008, respectively). The positive correlation between αvβ6 and MMP-9 in gastric cancer was confirmed by a correlation analysis. The Kaplan-Meier survival analysis showed that patients with expression of αvβ6 or MMP-9 alone died earlier than those with negative expression and that patients who were both αvβ6 and MMP-9 positive had a shorter overall survival than those with the opposite pattern (both αvβ6 and MMP-9 negative) (P = 0.000). A Cox model indicated that positive expression of αvβ6 and MMP-9, diffuse Lauren type, as well as a senior grade of N stage, M stage, and TNM stage were predictors of a poor prognosis in univariate analysis. Only αvβ6 and MMP-9 retained their significance when adjustments were made for other known prognostic factors in multivariate analysis (RR = 2.632, P = 0.003 and RR = 1.813, P = 0.007).

CONCLUSION: The expression of αvβ6 and MMP-9 are closely correlated, and the combinational pattern of αvβ6 and MMP-9 can serve as a more effective prognostic index for gastric cancer patients.

Innate Lymphoid Cells in Tumor Immunity

Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring.

Genetic deletion of TNFα inhibits ultraviolet radiation-induced development of cutaneous squamous cell carcinomas in PKCε transgenic mice via inhibition of cell survival signals

Protein kinase C epsilon (PKCε), a Ca(2+)-independent phospholipid-dependent serine/threonine kinase, is among the six PKC isoforms (α, δ, ε, η, μ, ζ) expressed in both mouse and human skin. Epidermal PKCε level dictates the susceptibility of PKCε transgenic (TG) mice to the development of cutaneous squamous cell carcinomas (SCC) elicited either by repeated exposure to ultraviolet radiation (UVR) or by using the DMBA initiation-TPA (12-O-tetradecanoylphorbol-13-acetate) tumor promotion protocol (Wheeler,D.L. et al. (2004) Protein kinase C epsilon is an endogenous photosensitizer that enhances ultraviolet radiation-induced cutaneous damage and development of squamous cell carcinomas. Cancer Res., 64, 7756-7765). Histologically, SCC in TG mice, like human SCC, is poorly differentiated and metastatic. Our earlier studies to elucidate mechanisms of PKCε-mediated development of SCC, using either DMBA-TPA or UVR, indicated elevated release of cytokine TNFα. To determine whether TNFα is essential for the development of SCC in TG mice, we generated PKCε transgenic mice/TNFα-knockout (TG/TNFαKO) by crossbreeding TNFαKO with TG mice. We now present that deletion of TNFα in TG mice inhibited the development of SCC either by repeated UVR exposures or by the DMBA-TPA protocol. TG mice deficient in TNFα elicited both increase in SCC latency and decrease in SCC incidence. Inhibition of UVR-induced SCC development in TG/TNFαKO was accompanied by inhibition of (i) the expression levels of TNFα receptors TNFRI and TNFRII and cell proliferation marker ornithine decarboxylase and metastatic markers MMP7 and MMP9, (ii) the activation of transcription factors Stat3 and NF-kB and (iii) proliferation of hair follicle stem cells and epidermal hyperplasia. The results presented here provide the first genetic evidence that TNFα is linked to PKCε-mediated sensitivity to DMBA-TPA or UVR-induced development of cutaneous SCC.

Mechanisms of Invasion in Head and Neck Cancer

CONTEXT

The highly invasive properties demonstrated by head and neck squamous cell carcinoma (HNSCC) are often associated with locoregional recurrence and lymph node metastasis in patients and is a key factor leading to an expected 5-year survival rate of approximately 50% for patients with advanced disease. It is important to understand the features and mediators of HNSCC invasion so that new treatment approaches can be developed.

OBJECTIVES

To provide an overview of the characteristics, mediators, and mechanisms of HNSCC invasion.

DATA SOURCES

A literature review of peer-reviewed articles in PubMed on HNSCC invasion.

CONCLUSIONS

Histologic features of HNSCC tumors can help predict prognosis and influence clinical treatment decisions. Cell surface receptors, signaling pathways, proteases, invadopodia function, epithelial-mesenchymal transition, microRNAs, and tumor microenvironment are all involved in the regulation of the invasive behavior of HNSCC cells. Identifying effective HNSCC invasion inhibitors has the potential to improve outcomes for patients by reducing the rate of spread and increasing responsiveness to chemoradiation.

Switch from αvβ5 to αvβ6 integrin is required for CD9-regulated keratinocyte migration and MMP-9 activation

Our previous research found that tetraspanin CD9 is downregulated in migrating epidermis during wound healing, and CD9 downregulation contributes to keratinocyte migration via matrix metalloproteinase-9 (MMP-9) activation. However, little is known about the mechanisms involved in CD9-regulated keratinocyte migration and MMP-9 activation. In this study, we revealed that the expressions of integrin subunits β5 and β6 were regulated by CD9. Furthermore, CD9 silencing triggered the switch from αvβ5 to αvβ6 integrin in HaCaT keratinocytes and CD9 overexpression reversed the switch. Importantly, integrin αvβ6 functional blocking antibody 10D5 significantly inhibited CD9 silencing-induced keratinocyte migration and MMP-9 activation, suggesting that the switch from αvβ5 to αvβ6 integrin plays a key role in CD9-regulated cell migration and MMP-9 activation in keratinocytes.

Suppression of Hedgehog signalling promotes pro-tumourigenic integrin expression and function

Aberrant Hedgehog (Hh) signalling has been reported in a number of malignancies, particularly basal cell carcinoma (BCC) of the skin. Clinical trials of Hh inhibitors are underway in many cancers, and these have produced significant clinical benefit in BCC patients, although regrowth of new, or clinically aggressive, variants, as well as development of secondary malignancies, has been reported. αvβ6 integrin is expressed in many cancers, where it has been shown to correlate with an aggressive tumour phenotype and poor prognosis. We have previously reported αvβ6 up-regulation in aggressive, morphoeic BCC variants, where it modulates the stromal response and induces invasion. To examine a possible link between Hh and αvβ6 function, we generated BCC models, overexpressing Gli1 in immortalized keratinocytes (NTert1, HaCaT). Unexpectedly, we found that suppressing Gli1 significantly increased αvβ6 expression. This promoted tumour cell motility and also stromal myofibroblast differentiation through integrin-dependent TGF-β1 activation. Gli1 inhibited αvβ6 expression by suppressing TGF-β1-induced Smad2/3 activation, blocking a positive feedback loop maintaining high αvβ6 levels. A similar mechanism was observed in AsPC1 pancreatic cancer cells expressing endogenous Gli1, suggesting a common mechanism across tumour types. In vitro findings were supported using human clinical samples, where we showed an inverse correlation between αvβ6 and Gli1 expression in different BCC subtypes and pancreatic cancers. In summary, we show that expression of Gli1 and αvβ6 inversely correlates in tumours in vivo, and Hh targeting up-regulates TGF-β1/Smad2/3-dependent αvβ6 expression, promoting pro-tumourigenic cell functions in vitro. These results have potential clinical significance, given the reported recurrence of BCC variants and secondary malignancies in patients treated by Hh targeting.

12-Hydroxyheptadecatrienoic acid promotes epidermal wound healing by accelerating keratinocyte migration via the BLT2 receptor

Endogenous 12-HHT, or a synthetic BLT2 agonist promotes epidermal wound closure by stimulating BLT2 on keratinocytes, inducing TNF and MMP production.

Leukotriene B₄ (LTB₄) receptor type 2 (BLT2) is a G protein–coupled receptor (GPCR) for 12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT) and LTB₄. Despite the well-defined proinflammatory roles of BLT1, the in vivo functions of BLT2 remain elusive. As mouse BLT2 is highly expressed in epidermal keratinocytes, we investigated the role of the 12-HHT/BLT2 axis in skin wound healing processes. 12-HHT accumulated in the wound fluid in mice, and BLT2-deficient mice exhibited impaired re-epithelialization and delayed wound closure after skin punching. Aspirin administration reduced 12-HHT production and resulted in delayed wound closure in wild-type mice, which was abrogated in BLT2-deficient mice. In vitro scratch assay using primary keratinocytes and a keratinocyte cell line also showed that the 12-HHT/BLT2 axis accelerated wound closure through the production of tumor necrosis factor α (TNF) and matrix metalloproteinases (MMPs). A synthetic BLT2 agonist accelerated wound closure in cultured cells as well as in C57BL/6J and diabetic mice. These results identify a novel mechanism underlying the action of the 12-HHT/BLT2 axis in epidermal keratinocytes and accordingly suggest the use of BLT2 agonists as therapeutic agents to accelerate wound healing, particularly for intractable wounds, such as diabetic ulcers.

Lycopene modulates THP1 and Caco2 cells inflammatory state through transcriptional and nontranscriptional processes

We revisited the action of a carotenoid, the lycopene, on the expression of proinflammatory genes, reactive oxygen species (ROS) production, and metalloprotease (MMP9) activity. THP1 and Caco2 cell lines were used as in vitro models for the two main cell types found in intestine tissue, that is, monocytes and epithelial cells. Proinflammatory condition was induced using either phorbol ester acetate (PMA), lipopolysaccharide (LPS) or tumor necrosis factor (TNF). In THP1 cells, short term pretreatment (2 h) with a low concentration (2 μM) of lycopene reinforce proinflammatory gene expression. The extent of the effect of lycopene is dependent on the proinflammtory stimulus (PMA, LPS or TNF) used. Lycopene enhanced MMP9 secretion via a c-AMP-dependent process, and reduced ROS production at higher concentrations than 2 μM. Cell culture media, conditioned by PMA-treated monocytes and then transferred on CaCo-2 epithelial cells, induced a proinflammatory state in these cells. The extent of this inflammatory effect was reduced when cells has been pretreated (12 h) with lycopene. At low concentration (2 μM or less), lycopene appeared to promote an inflammatory state not correlated with ROS modulation. At higher concentration (5 μM–20 μM), an anti-inflammatory effect takes place as a decrease of ROS production was detected. So, both concentration and time have to be considered in order to define the exact issue of the effect of carotenoids present in meals.

Molecular mechanisms of mouse skin tumor promotion

Multiple molecular mechanisms are involved in the promotion of skin carcinogenesis. Induction of sustained proliferation and epidermal hyperplasia by direct activation of mitotic signaling pathways or indirectly in response to chronic wounding and/or inflammation, or due to a block in terminal differentiation or resistance to apoptosis is necessary to allow clonal expansion of initiated cells with DNA mutations to form skin tumors. The mitotic pathways include activation of epidermal growth factor receptor and Ras/Raf/mitogen-activated protein kinase signaling. Chronic inflammation results in inflammatory cell secretion of growth factors and cytokines such as tumor necrosis factor-α and interleukins, as well as production of reactive oxygen species, all of which can stimulate proliferation. Persistent activation of these pathways leads to tumor promotion.

Role of macrophages in malignancy

Macrophages themselves are a heterogeneous mixture of cells which mediate their effects not only through phagocytosis but also through the production of various soluble factors such as cytokines and chemokines. The most important function of macrophages is the defense of the body against pathogen aggressions. However, when recruited within neoplastic tissues, tumor-associated macrophages polarize differently and do not predominantly exert their immune function but rather favor tumor growth and angiogenesis.

The role of inflammatory mediators in the development of prostatic hyperplasia and prostate cancer

Benign prostatic hyperplasia and prostate cancer remain the most prevalent urologic health concerns affecting elderly men in their lifetime. Only 20% of benign prostatic hyperplasia and prostate cancer cases coexist in the same zone of the prostate and require a long time for initiation and progression. While the pathogenesis of both diseases is not fully understood, benign prostatic hyperplasia and prostate cancer are thought to have a multifactorial etiology, their incidence and prevalence are indeed affected by age and hormones, and they are associated with chronic prostatic inflammation. At least 20% of all human malignancies arise in a tissue microenvironment dominated by chronic or recurrent inflammation. In prostate malignancy, chronic inflammation is an extremely common histopathologic finding; its origin remains a subject of debate and may in fact be multifactorial. Emerging insights suggest that prostate epithelium damage potentially inflicted by multiple environmental factors such as infectious agents, dietary carcinogens, and hormones triggers procarcinogenic inflammatory processes and promotes cell transformation and disease development. Also, the coincidence of chronic inflammation and tumorigenesis in the peripheral zone has recently been linked by studies identifying so-called proliferative inflammatory atrophy as a possible precursor of prostatic intraepithelial neoplasia and prostate cancer. This paper will discuss the available evidence suggesting that chronic inflammation may be involved in the development and progression of chronic prostatic disease, although a direct causal role for chronic inflammation or infection in prostatic carcinogenesis has yet to be established in humans. Further basic and clinical research in the area, trying to understand the etiology of prostatic inflammation and its signaling pathway may help to identify new therapeutic targets and novel preventive strategies for reducing the risk of developing benign and malignant tumors of the prostate.

A new isoform of steroid receptor coactivator-1 is crucial for pathogenic progression of endometriosis

Endometriosis is considered to be an estrogen-dependent inflammatory disease, but its etiology is unclear. Thus far, a mechanistic role for steroid receptor coactivators (SRCs) in the progression of endometriosis has not been elucidated. An SRC-1-null mouse model reveals that the mouse SRC-1 gene has an essential role in endometriosis progression. Notably, a previously unidentified 70-kDa SRC-1 proteolytic isoform is highly elevated both in the endometriotic tissue of mice with surgically induced endometriosis and in endometriotic stromal cells biopsied from patients with endometriosis compared to normal endometrium. Tnf⁻/⁻ and Mmp9⁻/⁻ mice with surgically induced endometriosis showed that activation of tumor necrosis factor a (TNF-α)-induced matrix metallopeptidase 9 (MMP9) activity mediates formation of the 70-kDa SRC-1 C-terminal isoform in endometriotic mouse tissue. In contrast to full-length SRC-1, the endometriotic 70-kDa SRC-1 C-terminal fragment prevents TNF-α-mediated apoptosis in human endometrial epithelial cells and causes the epithelial-mesenchymal transition and the invasion of human endometrial cells that are hallmarks of progressive endometriosis. Collectively, the newly identified TNF-α-MMP9-SRC-1 isoform functional axis promotes pathogenic progression of endometriosis.

The biological behaviors of rat dermal fibroblasts can be inhibited by high levels of MMP9

Aims. To explore the effects of the high expression of MMP9 on biological behaviors of fibroblasts. Methods. High glucose and hyperhomocysteine were used to induce MMP9 expression in skin fibroblasts. Cell proliferation was detected by flow cytometry and cell viability by CCK-8. ELISA assay was used to detect collagen (hydroxyproline) secretion. Scratch test was employed to evaluate horizontal migration of cells and transwell method to evaluate vertical migration of cells. Results. The mRNA and protein expressions of MMP9 and its protease activity were significantly higher in cells treated with high glucose and hyperhomocysteine than those in control group. At the same time, the S-phase cell ratio, proliferation index, cell viability, collagen (hydroxyproline) secretion, horizontal migration rate, and the number of vertical migration cells decreased in high-glucose and hyperhomocysteine-treated group. Tissue inhibitor of metalloproteinase 1 (TIMP1), which inhibits the activity of MMP9, recovered the above biological behaviors. Conclusions. High expression of MMP9 in skin fibroblasts could be induced by cultureing in high glucose and hyperhomocysteine medium, which inhibited cell biological behaviors. Inhibitions could be reversed by TIMP1. The findings suggested that MMP9 deters the healing of diabetic foot ulcers by inhibiting the biological behaviors of fibroblasts.

TNF: a tumor-suppressing factor or a tumor-promoting factor?

TNF-α is a major inflammatory cytokine named for its ability to induce rapid hemorrhagic necrosis of experimental cancers. During efforts to harness this antitumor activity in cancer treatments in the 1980s, a paradoxical tumor-promoting role of TNF became apparent. The cellular and molecular complexity of mammalian tumor microenvironments makes these opposing effects difficult to study. The fruit fly Drosophila melanogaster provides a simpler model system for studying complex cellular and genetic interactions that lead to tumor formation and progression. The paper from Marcos Vidal's group shows that both the tumor-suppressing and tumor-promoting roles of TNF are conserved in Drosophila, and that oncogenic Ras is the switch. The links between inflammation and cancer are now more fully understood, but it is still not clear whether TNF has potential as a target or a therapeutic in malignant disease, or both. Research in an invertebrate organism may provide important insights.

The Roles of ADAMs Family Proteinases in Skin Diseases

A disintegrin and metalloproteinases (ADAMs) are members of a new gene family of transmembrane and secreted proteins, which belong to the zinc proteinase superfamily. These molecules are involved in various biological events such as cell adhesion, cell fusion, cell migration, membrane protein shedding, and proteolysis. Growing evidence now attests to the potential involvement of ADAMs proteinases in diverse processes such as skin wound healing, inflammation, pigmentation, tumor development, cell proliferation, and metastasis. This paper focuses on the roles of ADAMs proteinases in a wide variety of skin diseases.

Impairment of human keratinocyte mobility and proliferation by advanced glycation end products-modified BSA

The migration and proliferation of keratinocytes is critical to wound re-epithelialization and defects in this function are associated with the clinical phenomenon of chronic non-healing wounds. Advanced glycation end products (AGEs) occur through non-enzymatic glycation of long-lived proteins in diabetes and play important roles in diabetic complications. However, specific roles for AGEs in keratinocyte migration and proliferation, and the underlying molecular mechanisms, have not been fully established. The aim of the current study was to elucidate the interaction between AGE-modified bovine serum albumin (AGE-BSA) and keratinocytes. As a result, we found that AGE-BSA had no effect on the viability of keratinocytes for up to 48 h of incubation with 50 μg/ml of AGE-BSA. AGE-BSA (but not non-glycated BSA) exerted a concentration-dependent suppression of keratinocyte migration at a range of concentrations. The expression of matrix metalloproteinase-9 (MMP-9) was significantly up-regulated in keratinocytes incubated with increasing AGE-BSA, but tissue inhibitor of metalloproteinases-1 (TIMP-1) expression was down-regulated. AGE-BSA also profoundly depressed phospho-focal adhesion kinase-Tyr397 (p-FAK) and α2β1 integrin expression, while total-FAK expression levels remained constant, in keratinocytes. The proliferative capacity of keratinocytes was diminished after 72 h AGE-BSA incubation. Taken together, these findings suggested that in the presence of AGE-BSA, keratinocytes lose their migratory and proliferation abilities. These data also indicated that, in the context of the chronic hyperglycemia in diabetes, the effects of AGE-BSA on keratinocyte migration might be mediated through MMP-9/TIMP-1, p-FAK and α2β1 integrin.

Betel-derived alkaloid up-regulates keratinocyte alphavbeta6 integrin expression and promotes oral submucous fibrosis

Oral submucous fibrosis (OSF) is a premalignant, fibrosing disorder of the mouth, pharynx, and oesophagus, with a malignant transformation rate of 7-13%. OSF is strongly associated with areca (betel) nut chewing and worldwide, over 5 million people are affected. As αvβ6 integrin is capable of promoting both tissue fibrosis and carcinoma invasion, we examined its expression in fibroepithelial hyperplasia and OSF. αvβ6 was markedly up-regulated in OSF, with high expression detected in 22 of 41 cases (p < 0.001). We investigated the functional role of αvβ6 using oral keratinocyte-derived cells genetically modified to express high αvβ6 (VB6), and also NTERT-immortalized oral keratinocytes, which express low αvβ6 (OKF6/TERT-1). VB6 cells showed significant αvβ6-dependent activation of TGF-β1, which induced transdifferentiation of oral fibroblasts into myofibroblasts and resulted in up-regulation of genes associated with tissue fibrosis. These experimental in vitro findings were confirmed using human clinical samples, where we showed that the stroma of OSF contained myofibroblasts and that TGF-β1-dependent Smad signalling was detectable both in keratinocytes and in myofibroblasts. We also found that arecoline, the major alkaloid of areca nuts, up-regulated keratinocyte αvβ6 expression. This was modulated through the M(4) muscarinic acetylcholine receptor and was suppressed by the M(4) antagonist, tropicamide. Arecoline-dependent αvβ6 up-regulation promoted keratinocyte migration and induced invasion, raising the possibility that this mechanism may support malignant transformation. Over 80% of OSF-related oral cancers examined had moderate/high αvβ6 expression. These data suggest that the pathogenesis of OSF may be epithelial-driven and involve arecoline-dependent up-regulation of αvβ6 integrin.

Oxidative stress induced mechanisms in the progression of periodontal diseases and cancer: a common approach to redox homeostasis?

There is documented evidence of significant associations between cancer of the lung, kidney, pancreas, hematological and oral cancers and periodontal diseases of the supporting structures of the teeth. Enhanced lipid peroxidation, raised levels of TBARS and the oxidative stress marker malondealdehyde have been detected in breast cancer with reduced antioxidant capacity, also characteristic of periodontal diseases. Antioxidants could overcome this deficit and attenuate disease progression by down regulating glutathione detoxification/redox buffering system and inhibiting key transcription factors. Periodontal disease may be a critical marker of a susceptible immune system, or initiate cancer risk with a pro-oxidant inflammatory profile.

Insulin resistance raises the risk for recurrence of stage I hepatocellular carcinoma after curative radiofrequency ablation in hepatitis C virus-positive patients: A prospective, case series study

AIM

Several studies have reported that insulin resistance raises the risk of primary hepatocellular carcinoma (HCC). We conducted a prospective, case series study to test the impact of insulin resistance on the recurrence after curative radiofrequency ablation (RFA) of stage I HCC in HCV-positive patients.

METHODS

From January 2006 to December 2007, 226 consecutive patients underwent treatment for primary HCC at our institutions, including 37 stage I cases. Among them, 33 were HCV-positive, and three, six and 24 received curative surgery, transarterial chemoembolization or RFA, respectively. In the 24 patients treated with RFA, recurrence-free survival was analyzed using the Kaplan-Meier method. The factors contributing to recurrence of HCC were subjected to univariate and multivariate analyses using the Cox proportional hazards model. Insulin resistance was estimated by the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR).

RESULTS

Kaplan-Meier analysis showed that the recurrence-free survival was lower in patients with higher HOMA-IR (>2.3, P = 0.0252) or with lower serum albumin level (<3.3 g/dL, P = 0.0004). In the univariate analysis, HOMA-IR (P = 0.0420) and albumin (P = 0.0036) were significantly associated with recurrence of HCC. Multivariate analysis revealed albumin (odds ratio = 0.01, 95% confidence interval = 0.0002-0.015, P = 0.0001) and HOMA-IR (odds ratio = 3.85, 95% confidence interval = 1.57-14.2, P = 0.0015) to be independent predictors for recurrence of HCC.

CONCLUSION

Serum albumin level and HOMA-IR were independent risk factors for recurrence of stage I HCC after curative RFA in HCV-positive patients. Patients with these factors require closer surveillance.

TNF-alpha regulates the effects of irradiation in the mouse bone marrow microenvironment

Background

Secondary bone marrow (BM) myelodysplastic syndromes (MDS) are increasingly common, as a result of radio or chemotherapy administered to a majority of cancer patients. Patients with secondary MDS have increased BM cell apoptosis, which results in BM dysfunction (cytopenias), and an increased risk of developing fatal acute leukemias. In the present study we asked whether TNF-α, known to regulate cell apoptosis, could modulate the onset of secondary MDS.

Principal Findings

We show that TNF-α is induced by irradiation and regulates BM cells apoptosis in vitro and in vivo. In contrast to irradiated wild type (WT) mice, TNF-α deficient (TNF-α KO) mice or WT mice treated with a TNF-α-neutralizing antibody were partially protected from the apoptotic effects of irradiation. Next we established a 3-cycle irradiation protocol, in which mice were sub-lethally irradiated once monthly over a 3 month period. In this model, irradiated WT mice presented loss of microsatellite markers on BM cells, low white blood cell (WBC) counts, reduced megakaryocyte (MK) and platelet levels (thrombocytopenia) and macrocytic anemia, phenoypes that suggest the irradiation protocol resulted in BM dysfunction with clinical features of MDS. In contrast, TNF-α KO mice were protected from the irradiation effects: BM cell apoptosis following irradiation was significantly reduced, concomitant with sustained BM MK numbers and absence of other cytopenias. Moreover, irradiated WT mice with long term (≥5 months) BM dysfunction had increased BM angiogenesis, MMPs and VEGF and NFkB p65, suggestive of disease progression.

Conclusion

Taken together, our data shows that TNF-α induction following irradiation modulates BM cell apoptosis and is a crucial event in BM dysfunction, secondary MDS onset and progression.

Vascular integrins: therapeutic and imaging targets of tumor angiogenesis

Cells, including endothelial cells, continuously sense their surrounding environment and rapidly adapt to changes in order to assure tissues and organs homeostasis. The extracellular matrix (ECM) provides a physical scaffold for cell positioning and represents an instructive interface allowing cells to communicate over short distances. Cell surface receptors of the integrin family emerged through evolution as essential mediators and integrators of ECM-dependent communication. In preclinical studies, pharmacological inhibition of vascular integrins suppressed angiogenesis and inhibited tumor progression. alpha(V)beta(3) and alpha(V)beta(5) were the first integrins targeted to suppress tumor angiogenesis. Subsequently, additional integrins, in particular alpha(1)beta(1), alpha(2)beta(1), alpha(5)beta(1), and alpha(6)beta(4), emerged as potential therapeutic targets. Integrin inhibitors are currently tested in clinical trials for their safety and antiangiogenic/antitumor activity. In this chapter, we review the role of integrins in angiogenesis and present recent advances in the use of integrin antagonists as potential therapeutics in cancer and discuss future perspectives.

Systemic anti-VEGF treatment strongly reduces skin inflammation in a mouse model of psoriasis

Although(,) vascular remodeling is a hallmark of many chronic inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, anti-vascular strategies to treat these conditions have received little attention to date. We investigated the anti-inflammatory activity of systemic blockade of VEGF-A by the inhibitory monoclonal antibody G6-31, employing a therapeutic trial in a mouse model of psoriasis. Simultaneous deletion of JunB and c-Jun (DKO*) in the epidermis of adult mice leads to a psoriasis-like phenotype with hyper- and parakeratosis and increased subepidermal vascularization. Moreover, an inflammatory infiltrate and elevated levels of cytokines/chemokines including TNFalpha, IL-1alpha/beta, IL-6, and the innate immune mediators IL-22, IL-23, IL-23R, and IL-12p40 are detected. Here we show that anti-VEGF antibody treatment of mice already displaying disease symptoms resulted in an overall improvement of the psoriatic lesions leading to a reduction in the number of blood vessels and a significant decrease in the size of dermal blood and lymphatic vessels. Importantly, anti-VEGF-treated mice showed a pronounced reduction of inflammatory cells within the dermis and a normalization of epidermal differentiation. These results demonstrate that systemic blockade of VEGF by an inhibitory antibody might be used to treat patients who have inflammatory skin disorders such as psoriasis.

Blocking TNF-alpha attenuates aneurysm formation in a murine model

Abdominal aortic aneurysm (AAA) is one of a number of diseases associated with a prominent inflammatory cell infiltrate and local destruction of structural matrix macromolecules. This chronic infiltrate is predominately composed of macrophages and T lymphocytes. Activated macrophages produce a variety of cytokines, including TNF-alpha. Elevated levels of TNF-alpha were observed in patients with AAA, suggesting that TNF-alpha may play a role in the pathogenic mechanisms of AAA. In the present study, we investigated the role of TNF-alpha in AAA formation. By studying a murine aneurysm model, we found that both mRNA and protein levels of TNF-alpha were increased in aneurysm tissue compared with normal aortic tissues. Therefore, we tested the response of mice lacking expression of TNF-alpha. These mice were resistant to aneurysm formation. Our results show that TNF-alpha deficiency attenuates matrix metalloproteinase (MMP) 2 and MMP-9 expression and macrophage infiltration into the aortic tissue. These data suggest that TNF-alpha plays a central role in regulating matrix remodeling and inflammation in the aortic wall leading to AAA. In addition, we investigated the pharmacological inhibition of AAA. A Food and Drug Administration-approved TNF-alpha antagonist, infliximab, inhibited aneurysm growth. Our data also show that infliximab treatment attenuated elastic fiber disruption, macrophage infiltration, and MMP-2 and MMP-9 expression in aortic tissue. This study confirms that a strategy of TNF-alpha antagonism may be an important therapeutic strategy for treating AAA.

MMP-13 plays a role in keratinocyte migration, angiogenesis, and contraction in mouse skin wound healing

Matrix metalloproteinases (MMPs) have been implicated in wound healing. To analyze the roles of MMP-9 and MMP-13 in wound healing, we generated full-thickness cutaneous wounds in MMP-9 knockout (KO), MMP-13 KO, MMP-9/13 double KO, and wild-type mice. Macroscopic wound closure was delayed in all of the KO mice, as compared with wild-type mice. The rate of re-epithelialization was significantly delayed in MMP-9 KO and MMP-13 KO mice and remarkably delayed in MMP-9/13 double KO mice, as compared with wild-type mice. Both MMP-9 and MMP-13 were expressed by the leading edges of epidermal cells in wild-type mice, and the migration of keratinocytes was suppressed by treatment with an MMP inhibitor or transfection of small interfering RNAs for MMP-9 or MMP-13, as compared with controls. The vascular density in wound granulation was significantly lower in both MMP-13 KO and MMP-9/13 double KO mice than in wild-type mice. Degradation of connective tissue growth factor in wound tissue was transiently prevented in MMP-13 KO mice. Morphometric analyses demonstrated a reduction in both wound contraction and myofibroblast formation in both MMP-13 KO and MMP-9/13 double KO mice. Proliferation and transforming growth factor-beta1-induced myofibroblast differentiation of dermal fibroblasts from MMP-13 KO mice were decreased, as compared with wild-type dermal fibroblasts. These data suggest that MMP-13 plays a role in keratinocyte migration, angiogenesis, and contraction in wound healing, while MMP-9 functions in keratinocyte migration.

Expression of MMP9 and CD147 in invasive squamous cell carcinoma of the uterine cervix and their implication

Matrix metalloproteinase 9 (MMP9) and CD147 play a role in invasion and metastasis of many types of human malignancies. The correlation of the expression of MMP9 and CD147 with invasion and metastasis of invasive squamous cell carcinoma (SCC) of the uterine cervix has not been examined. In the present study, RT-PCR assay was used to detect the expression level of MMP9 mRNA semiquantitatively, and immunohistochemical stain was adapted to evaluate the score of CD147 on the cell membrane or in the cytoplasm of tumor cells of 65 cases of invasive squamous cell carcinoma of the uterine cervix and 21 cases of chronic cervitis tissues. MMP9 and CD147 expression in correlation with invasion, metastasis, and differentiation of invasive SCC of the uterine cervix was analyzed statistically. We found that MMP9 and CD147 expression was elevated significantly in tumor tissue compared to the control (cervical epithelium of chronic cervitis) (P<0.01). In the comparison of MMP9 and CD147 expression in 47 cases with lymph node metastasis and 18 cases without lymph node metastasis, there was a significantly higher expression of MMP9 and CD147 in the group with lymph node metastasis (P<0.05 for MMP9, P<0.01 for CD147). MMP9 expression was significantly higher in 24 cases of poor differentiation than in 41 cases of moderate differentiation (P<0.05). No difference was found in CD147 expression between poor and moderate differentiation (P>0.05). No significant difference in MMP9 and CD147 expression levels was obtained between 26 cases of FIGO stage I tumors and 39 cases of stage II tumors (P>0.05 for MMP9, P>0.05 CD147). There was no correlation between MMP9 or CD147 expression levels and the resected tumor size (P>0.05). The positive correlation (r=0.568, P<0.001) of MMP9 expression and CD147 score was seen in the tumor tissues of 65 cases. The data in this study show that MMP9 and CD147 expression are correlated with invasion, metastasis of squamous cell carcinoma of the uterine cervix, and that MMP9 expression is correlated with poor differentiation of invasive squamous cell carcinoma of the uterine cervix.

Expression of endoglin (CD105) in cervical cancer

In this study, we have investigated the role of endoglin (CD105), a regulator of transforming growth factor (TGF)-β₁ signalling on endothelial cells, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor-A (VEGF-A) in cervical cancer. We have measured the number and determined the location of both newly formed (CD105-positive) and the overall number of (CD31-positive) blood vessels, and bFGF and VEGF-A expression using immunohistochemistry in 30 cervical carcinoma specimens. Vascular endothelial growth factor-A mRNA expression was determined using RNA-in situ hybridisation. CD105- and CD31-positive vessels and bFGF- and VEGF-A-positive cells were predominantly present in the stroma. The presence of CD105- and CD31-positive vessels in the stroma did neither correlate with the number of VEGF-A-positive cells nor the number of bFGF-positive cells. However, the number of CD105- and CD31-positive vessels was associated with the expression of VEGF-A mRNA in the epithelial cell clusters (P=0.013 and P=0.005, respectively). The presence of CD105-positive and CD31-positive vessels was associated with the expression of αvβ6 (a TGF-β₁ activator; P=0.013 and P=0.006, respectively). Clinically, the number of CD105-positive vessels associated with the number of lymph node metastasis (P<0.001). Furthermore, the presence of CD105-positive vessels within the epithelial cell clusters associated with poor disease-free survival (P=0.007).

The role of TNF in cancer

Tumor necrosis factor (TNF) is an extraordinarily pleiotropic cytokine with a central role in immune homeostasis, inflammation, and host defense. Dependent on the cellular context, it can induce such diverse effects as apoptosis, necrosis, angiogenesis, immune cell activation, differentiation, and cell migration. These processes are of great relevance in tumor immune surveillance, and also play crucial roles in tumor development and tumor progression. It is therefore no surprise that TNF in a context-dependent manner displays pro- and antitumoral effects. Modulation of the activity of the TNF-TNF receptor system thus offers manifold possibilities for cancer therapy. In fact, TNF in combination with melphalan is already an established treatment option in the therapy of advanced soft tissue sarcoma of the extremities and many preclinical data suggest that TNF neutralization could also be exploited to fight cancer or cancer-associated complications.

Immune cells as mediators of solid tumor metastasis

Outgrowths of disseminated metastases remain the primary cause of mortality in cancer patients; however, molecular and cellular mechanisms regulating metastatic spread remain largely elusive. Recent insights into these mechanisms have refined the seed and soil hypothesis and it is now recognized that metastasis of solid tumors requires collaborative interactions between malignant cells and a diverse assortment of "activated" stromal cells at both primary and secondary tumor locations. Specifically, persistent pro-tumor immune responses (inflammation), now generally accepted as potentiating primary tumor development, are also being recognized as mediators of cancer metastasis. Thus, novel anti-cancer therapeutic strategies targeting molecular and/or cellular mechanisms regulating these collaborative interactions may provide efficacious relief for metastatic disease. This review focuses on recent literature revealing new mechanisms whereby immune cells regulate metastatic progression, with a primary focus on breast cancer.

Expression of MMP-9, MMP-10 and TNF-alpha and lack of epithelial MMP-1 and MMP-26 characterize pyoderma gangrenosum

BACKGROUND

Pyoderma gangrenosum (PG) is a non-infectious, autoimmune, chronic ulcer of the skin, often co-existing with inflammatory bowel disease (IBD). Matrix metalloproteinases (MMPs) have been implicated as mediators of tissue destruction in chronic cutaneous and intestinal wounds.

METHODS

Twenty-four skin biopsies with clinically and histologically confirmed PG and acute wounds were immunostained for MMP-1, -7, -8, -9, -10 and -26; tissue inhibitors of matrix metalloproteinase (TIMP)-1 and -3 and tumor necrosis factor-alpha (TNF-alpha).

RESULTS

MMP-1 was generally expressed by keratinocytes distal from the wound edge, whereas MMP-10 was detected abundantly in the epithelium. MMP-26 was positive in 42% at the migratory front. Abundant stromal expression was evident for MMP-1, -9 and -10, TIMP-1 and -3 and TNF-alpha. In acute wounds, stromal MMP-1, -9 and -10 and TNF-alpha were sparse.

CONCLUSIONS

Unlike in normally healing cutaneous wounds, MMP-1 and -26 were detected bordering the wound in only a minority of PGs and their lack may thus retard epithelial repair. Particularly, MMP-9 and -10 and TNF-alpha would be suitable therapeutic targets as they may contribute to the degradation of provisional matrices needed for migration in healing wounds. The presence of MMP-1, -9, -10 and -26 in both PG and IBD ulcers may suggest a similar pathogenesis for cutaneous and mucosal inflammation.

Trichostatin A, a histone deacetylase inhibitor, attenuates invasiveness and reactivates E-cadherin expression in immortalized endometriotic cells

The objective of this study is to determine whether trichostatin A (TSA) can suppress the invasiveness of 2 endometriotic cell lines known to be invasive and E-cadherin negative. The membrane invasion culture system was used to assess cell invasion using invasive and a noninvasive bladder cancer cell lines as positive and negative controls, respectively. The E-cadherin mRNA levels and protein expression were evaluated by real-time reverse transcriptase polymerase chain reaction and Western blot analysis, respectively. The authors found that TSA attenuates the invasiveness of 2 cell lines in the presence or absence of tumor necrosis factor alpha (TNFalpha) stimulation. In addition, TSA treatment reactivates E-cadherin gene and protein expression in these cell lines. These results, along with recent findings that TSA suppresses proliferation, interleukin-1 beta-induced cyclo-oxygenase 2 expression, and constitutive or TNFalpha-stimulated nuclear factor kappa B activation in endometrial and endometriotic cells, makes histone deacetylase inhibitors a promising class of compounds for novel and more effective medical treatment of endometriosis, especially given the mounting evidence that endometrios be an epigenetic disease.

TNF-alpha in promotion and progression of cancer

Tumour necrosis factor alpha is a member of the TNF/TNFR cytokine superfamily. In common with other family members, TNF-alpha is involved in maintenance and homeostasis of the immune system, inflammation and host defence. However, there is a 'dark side' to this powerful cytokine; it is now clear that, especially in middle and old age, TNF-alpha is involved in pathological processes such as chronic inflammation, autoimmunity and, in apparent contradiction to its name, malignant disease. This article will discuss the involvement of TNF-alpha in the inflammatory network that contributes to all stages of the malignant process, and consider the possibility that TNF-alpha may be a target for cancer therapy.