v-Src activates the expression of 92-kDa type IV collagenase gene through the AP-1 site and the GT box homologous to retinoblastoma control elements. A mechanism regulating gene expression independent of that by inflammatory cytokines

Targeting sphingosine 1-phosphate and sphingosine kinases in pancreatic cancer: mechanisms and therapeutic potential

Pancreatic cancer is known to be the most lethal cancer. Fewer new treatments are being developed for pancreatic cancer as compared to other cancers. The bioactive lipid S1P, which is mainly regulated by sphingosine kinase 1 (SK1) and sphingosine kinase 2 (SK2) enzymes, plays significant roles in pancreatic cancer initiation and exacerbation. S1P controls many signaling pathways to modulate the progression of pancreatic cancer through the G-coupled receptor S1PR1-5. Several papers reporting amelioration of pancreatic cancer via modulation of S1P levels or downstream signaling pathways have previously been published. In this paper, for the first time, we have reviewed the results of previous studies to understand how S1P and its receptors contribute to the development of pancreatic cancer, and whether S1P can be a therapeutic target. In addition, we have also reviewed papers dealing with the effects of SK1 and SK2, which are kinases that regulate the level of S1P, on the pathogenesis of pancreatic cancer. We have also listed available drugs that particularly focus on S1P, S1PRs, SK1, and SK2 for the treatment of pancreatic cancer. Through this review, we would like to suggest that the SK/S1P/S1PR signaling system can be an important target for treating pancreatic cancer, where a new treatment target is desperately warranted.

The role of matrix metalloproteinase-9 in cardiac remodeling and dysfunction and as a possible blood biomarker in heart failure

Heart failure (HF) is the leading cause of morbidity and mortality in cardiovascular diseases, being responsible for many hospitalizations annually. HF is considered a public health problem with significant economic and social impact, which makes searches essential for strategies that improve the ability to predict and diagnose HF. In this way, biomarkers can help in risk stratification for a more personalized approach to patients with HF. Preclinical and clinical evidence shows the participation of matrix metalloproteinase 9 (MMP-9) in the HF process. In this review, we will demonstrate the critical role that MMP-9 plays in cardiac remodeling and dysfunction. We will also show its importance as a blood biomarker in acute and chronic HF patients.

GATA4 regulates the transcription of MMP9 to suppress the invasion and migration of breast cancer cells via HDAC1-mediated p65 deacetylation

GATA-binding protein 4 (GATA4) is recognized for its significant roles in embryogenesis and various cancers. Through bioinformatics and clinical data, it appears that GATA4 plays a role in breast cancer development. Yet, the specific roles and mechanisms of GATA4 in breast cancer progression remain elusive. In this study, we identify GATA4 as a tumor suppressor in the invasion and migration of breast cancer. Functionally, GATA4 significantly reduces the transcription of MMP9. On a mechanistic level, GATA4 diminishes MMP9 transcription by interacting with p65 at the NF-κB binding site on the MMP9 promoter. Additionally, GATA4 promotes the recruitment of HDAC1, amplifying the bond between p65 and HDAC1. This leads to decreased acetylation of p65, thus inhibiting p65's transcriptional activity on the MMP9 promoter. Moreover, GATA4 hampers the metastasis of breast cancer in vivo mouse model. In summary, our research unveils a novel mechanism wherein GATA4 curtails breast cancer cell metastasis by downregulating MMP9 expression, suggesting a potential therapeutic avenue for breast cancer metastasis.

TNFα blockade reverses vascular and uteroplacental matrix metalloproteinases imbalance and collagen accumulation in hypertensive pregnant rats

Preeclampsia is a pregnancy-related disorder of maternal hypertension-in-pregnancy (HTN-Preg) and often fetal growth restriction (FGR). Placental ischemia could be an initiating event leading to inadequate vascular and uteroplacental remodeling and HTN-Preg; however, the molecular targets are unclear. To test the hypothesis that placental ischemia-induced release of proinflammatory cytokines target vascular and uteroplacental matrix metalloproteinases (MMPs), we tested if infusing TNFα (200 ng/kg/day) in day-14 pregnant (Preg) rats causes MMP imbalance and collagen accumulation, and if infusing TNFα decoy receptor Etanercept (0.4 mg/kg/day) in HTN-Preg rats with reduced uteroplacental perfusion pressure (RUPP) reverses MMP imbalance and collagen accumulation. On gestational day-19, blood pressure (BP) was higher in Preg + TNFα and RUPP vs Preg rats, and restored in RUPP + Etanercept rats. Gelatin zymography and Western blots revealed decreases in MMP-2 and MMP-9 and increases in MMP-1 and MMP-7 in aorta, uterus and placenta of Preg + TNFα and RUPP, that were reversed in RUPP + Etanercept rats. Collagen-I and IV were abundant in Preg + TNFα and RUPP, and were decreased in RUPP + Etanercept rats. The litter size, uterine, placenta, and pup weight were markedly reduced in RUPP, insignificantly reduced in Preg + TNFα, and slightly improved in RUPP + Etanercept rats. Thus TNFα blockade reverses the decreases in vascular and uteroplacental MMP-2 and MMP-9, and the increases in MMP-1, MMP-7 and accumulation of collagen-I and IV induced by placental ischemia and TNFα in HTN-Preg rats. Targeting TNFα using cytokine antagonists, or MMPs using MMP modulators could rectify MMP imbalance and collagen accumulation, restore vascular and uteroplacental remodeling, and improve BP in HTN-Preg and preeclampsia.

Memantine protects blood-brain barrier integrity and attenuates neurological deficits through inhibiting nitric oxide synthase ser1412 phosphorylation in intracerebral hemorrhage rats: involvement of peroxynitrite-related matrix metalloproteinase-9/NLRP3 inflammasome activation

Memantine has demonstrated beneficial effects on several types of brain insults via therapeutic mechanisms mainly related to its activity as a receptor antagonist of N-methyl-d-aspartate. However, the influences of memantine on intracerebral hemorrhage (ICH) remain obscure. This research probed into the neurovascular protective mechanisms of memantine after ICH and its impacts on neuronal nitric oxide synthase (nNOS) ser1412 phosphorylation. ICH model was established by employing intrastriatal collagenase injection in rats. After modeling, rats were then allocated randomly into sham-operated (sham), vehicle-treated (ICH+V), and memantine-administrated (ICH+M) groups. Memantine (20 mg/kg/day) was intraperitoneally administered 30 min after ICH and thenceforth once daily. Rats were dedicated at 0.25, 6, 12, 24 h, 3 and 7 d post-ICH for measurement of corresponding indexes. Behavioral changes, brain edema, levels of nNOS ser1412 phosphorylation, peroxynitrite, matrix metalloproteinase (MMP)-9, NLRP3, IL-1β and numbers of dying neurons, as well as the cellular localization of gelatinolytic activity, were detected among the groups. Memantine improved the neurologic deficits and mitigated brain water content, levels of MMP-9, NLRP3, IL-1β and dying neurons. Additionally, treatment with memantine also reduced nNOS ser1412 phosphorylation and peroxynitrite formation compared with the ICH+V group at 24 h after ICH. In situ zymography simultaneously revealed that gelatinase activity was primarily colocalized with vessel walls and neurons. We concluded that memantine ameliorated blood-brain barrier disruption and neurologic dysfunction in an ICH rat model. The underlying mechanism might involve repression of nNOS ser1412 phosphorylation, as well as peroxynitrite-related MMP-9 and NLRP3 inflammasome activation.

TIMELESS inhibits breast cancer cell invasion and metastasis by down-regulating the expression of MMP9

Breast cancer is the first killer leading to female death, and tumor metastasis is one of the important factors leading to the death of patients, but the specific mechanism of breast cancer metastasis is not very clear at present. Our study showed that overexpression of TIMELESS could significantly inhibit the invasion and metastasis of breast cancer cells ZR-75-30 and the assembly of F-actin protein. On the contrary, knockdown of TIMELESS promoted the invasion and metastasis of breast cancer cells. Further study revealed that TIMELESS overexpression decreased the mRNA and protein levels of MMP9. Furthermore, TIMELESS could interact with p65, leading to repress the association of p65 and its acetyltransferase CBP and down-regulating the acetylation level of p65, which inhibited the activation of NF-κB signal pathway. In conclusion, our research showed that TIMELESS may repress the invasion and metastasis of breast cancer cells via inhibiting the acetylation of p65, inhibiting the activation of NF-κB, thus down-regulating the expression of MMP9, and then inhibiting the invasion and metastasis of breast cancer cells.

Geraniin inhibits oral cancer cell migration by suppressing matrix metalloproteinase-2 activation through the FAK/Src and ERK pathways

Geraniin has been reported to have numerous biological activities, including antiviral, antihypertensive, antihyperglycaemic, liver protective, antidiabetic, and apoptotic activities. However, the anti-migration effects of geraniin on oral cancer remain elusive. In this study, we revealed the potential antitumor mechanisms of geraniin through the inhibition of the migration and invasion of human oral cancer cell lines SCC-9 and SCC-14. The results of gelatin zymography and Western blot assays revealed that geraniin significantly reduced the activity and expression of matrix metalloproteinase-2 (MMP-2) of oral cancer cells in a concentration-dependent manner. Furthermore, geraniin potently suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-regulated kinase (ERK)1/2 but did not affect the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase 1/2. Moreover, blocking the MAPK/ERK1/2 pathway significantly enhanced the anti-migration ability of geraniin in oral cancer cells. In conclusion, we demonstrated that geraniin inhibits the motility of SCC-9 and SCC-14 cells in vitro through a molecular mechanism that involves the attenuation of MMP-2 expression and activity mediated by decreased FAK/Src and ERK1/2 pathways.

A Reporter System Evaluates Tumorigenesis, Metastasis, β-catenin/MMP Regulation, and Druggability

Cancer invasion, metastasis, and therapy resistance are the crucial phenomena in cancer malignancy. The high expression of matrix metalloproteinase 9 (MMP9) is a biomarker as well as a causal factor of cancer invasiveness and metastatic activity. However, a regulatory mechanism underlying MMP9 expression in cancer is not clarified yet. In addition, a new strategy for anticancer drug discovery is becoming an important clue. In the present study, we aimed (i) to develop a novel reporter system evaluating tumorigenesis, invasiveness, metastasis, and druggability with a combination of three-dimensional tumoroid model and Mmp9 promoter and (ii) to examine pharmacological actions of anticancer medications using this reporter system. High expression and genetic amplification of MMP9 were found in colon cancer cases. We found that proximal promoter sequences of MMP9 in murine and human contained conserved binding sites for transcription factors β-catenin/TCF/LEF, glucocorticoid receptor (GR), and nuclear factor kappa-B (NF-κB). The murine Mmp9 promoter (-569 to +19) was markedly activated in metastatic colon cancer cells and additionally activated by tumoroid formation and by β-catenin signaling stimulator lithium chloride. The Mmp9 promoter-driven fluorescent reporter cells enabled the monitoring of activities of MMP9/gelatinase, tumorigenesis, invasion, and metastasis in syngeneic transplantation experiments. We also demonstrated pharmacological actions as follows: dexamethasone and hydrocortisone, steroidal medications binding to GR, inhibited the Mmp9 promoter but did not inhibit tumorigenesis. On the contrary, antimetabolite 5-fluorouracil, a gold standard for colon cancer chemotherapy, inhibited tumoroid formation but did not inhibit Mmp9 promoter activity. Notably, antimalaria medication artesunate inhibited both tumorigenesis and the Mmp9 promoter in vitro, potentially through inhibition of β-catenin/TCF/LEF signaling. Thus, this novel reporter system enabled monitoring tumorigenesis, invasiveness, metastasis, key regulatory signalings such as β-catenin/MMP9 axis, and druggability. Impact Statement Cancer invasion and metastasis have been shown to be driven by matrix metalloproteinase 9 (MMP9), whose expression mechanism is not clarified yet. In addition, a new strategy for anticancer drug discovery is becoming important. We established a novel reporter system evaluating tumorigenesis, invasiveness, metastasis, and druggability with a combination of three-dimensional (3D) tumoroid model and Mmp9 promoter. Using this reporter system, we demonstrated pharmacological actions of anticancer medications such as antimetabolite 5-fluorouracil (5-FU) and antimalaria medication artesunate (ART), which inhibited both tumorigenesis and β-catenin/MMP regulatory signaling. Our study impacts the translational fields of oncology, drug discovery, and organoid model.

The gastroprotective effect of N-acetylcysteine and genistein in indomethacin-induced gastric injury in rats

The protective effect of N-acetylcysteine (NAC) and genistein (GEN) on an experimental model of indomethacin (IND)-induced gastric injury was investigated. A total of 50 male rats were divided into 5 groups: (1) control, (2) IND, (3) NAC pretreated, (4) GEN pretreated, and (5) NAC+GEN pretreated. Rats in groups 3-5 were orally administered NAC (500 mg/kg), GEN (10 mg/kg), or both, respectively, once daily for 7 days before the induction of gastric injury by IND (50 mg/kg). The stomach was removed for biochemical analysis and histopathological examination. Pretreatment with NAC, GEN, or both significantly improved ulcer indices and increased nitric oxide level and superoxide dismutase activity. They also significantly decreased malondialdehyde, tumour necrosis factor α levels, and myeloperoxidase activity, and downregulated matrix metalloproteinase 9 (MMP-9) gene expression compared to the IND group. NAC alone ameliorated IND-induced apoptosis, whereas GEN only significantly increased prostaglandin E₂ level. Further, coadministration of both resulted in a significantly better gastroprotective effect versus solo administration. Coadministration of NAC and GEN has an additive gastroprotective effect in IND-induced gastric injury, which may be through interaction of their potential cytoprotective, antioxidant, anti-inflammatory, and antiapoptotic mechanisms together with regulation of MMP-9 expression.

Matrix Metalloproteinases in Remodeling of Lower Extremity Veins and Chronic Venous Disease

The veins of the lower extremity are equipped with efficient wall, contractile vascular smooth muscle (VSM), and competent valves in order to withstand the high venous hydrostatic pressure in the lower limb and allow unidirectional movement of deoxygenated blood toward the heart. The vein wall structure and function are in part regulated by matrix metalloproteinases (MMPs). MMPs are zinc-dependent endopeptidases that are secreted as inactive pro-MMPs by different cells in the venous wall including fibroblasts, VSM, and leukocytes. Pro-MMPs are activated by other MMPs, proteinases, and other endogenous and exogenous activators. MMPs degrade various extracellular matrix (ECM) proteins including collagen and elastin, and could affect other cellular processes including endothelium-mediated dilation, VSM cell migration, and proliferation as well as modulation of Ca²⁺ signaling and contraction in VSM. It is thought that increased lower limb venous hydrostatic pressure increases hypoxia-inducible factors and other MMP inducers such as extracellular matrix metalloproteinase inducer, leading to increased MMP expression/activity, ECM protein degradation, vein wall relaxation, and venous dilation. Vein wall inflammation and leukocyte infiltration cause additional increases in MMPs, and further vein wall dilation and valve degradation, that could lead to chronic venous disease and varicose veins (VVs). VVs are often presented as vein wall dilation and tortuosity, incompetent venous valves, and venous reflux. Different regions of VVs show different MMP levels and ECM proteins with atrophic regions showing high MMP levels/activity and little ECM compared to hypertrophic regions with little or inactive MMPs and abundant ECM. Treatment of VVs includes compression stockings, venotonics, sclerotherapy, or surgical removal. However, these approaches do not treat the cause of VVs, and other lines of treatment may be needed. Modulation of endogenous tissue inhibitors of metalloproteinases (TIMPs), and exogenous synthetic MMP inhibitors may provide new approaches in the management of VVs.

Morin Inhibits Proliferation, Migration, and Invasion of Bladder Cancer EJ Cells via Modulation of Signaling Pathways, Cell Cycle Regulators, and Transcription Factor-Mediated MMP-9 Expression

Preclinical Research Previous studies have shown that morin exerts diverse pharmacological activities. In this study, we investigated the inhibitory activity of morin on bladder cancer EJ cells. Morin significantly inhibited EJ cell proliferation, which was related to the G1-phase cell cycle arrest together with the reduced expression of cyclin D1, cyclin E, CDK2, and CDK4 via increased expression of p21WAF1. Morin also increased ERK1/2 phosphorylation and decreased JNK and AKT phosphorylation without altering the p38MAPK phosphorylation levels. Morin treatment suppressed the migration and invasion of EJ cells in wound-healing and transwell cell invasion assays. Zymographic and electrophoretic mobility shift assays showed that morin suppressed the expression of matrix metalloproteinase-9 (MMP-9) via repression of the binding activity of AP-1, Sp-1, and NF-κB. Collectively, these results demonstrate that morin reduced cyclin D1, cyclin E, CDK2 and CDK4 expression via the induction of p21WAF1 expression, increased ERK1/2 phosphorylation and decreased JNK, and AKT phosphorylation, and prevented MMP-9 expression via the inhibition of transcription factors AP-1, Sp-1, and NF-κB, thereby resulting in the inhibition of growth, migration, and invasion of bladder cancer EJ cells. These results provide a novel insight into the use of morin in the prevention of bladder cancer. Drug Dev Res 78 : 81-90, 2017. © 2017 Wiley Periodicals, Inc.

Novel roles of Src in cancer cell epithelial-to-mesenchymal transition, vascular permeability, microinvasion and metastasis

The Src-family kinases (SFKs), an intracellularly located group of non-receptor tyrosine kinases are involved in oncogenesis. The importance of SFKs has been implicated in the promotion of tumor cell motility, proliferation, inhibition of apoptosis, invasion and metastasis. Recent evidences indicate that specific effects of SFKs on epithelial-to-mesenchymal transition (EMT) as well as on endothelial and stromal cells in the tumor microenvironment can have profound effects on tumor microinvasion and metastasis. Although, having been studied extensively, these novel features of SFKs may contribute to greater understanding of benefits from Src inhibition in various types of cancers. Here we review the novel role of SFKs, particularly c-Src in mediating EMT, modulation of tumor endothelial-barrier, transendothelial migration (microinvasion) and metastasis of cancer cells, and discuss the utility of Src inhibitors in vascular normalization and cancer therapy.

The association between blood glucose levels and matrix-metalloproteinase-9 in early severe sepsis and septic shock

Background

Hyperglycemia is a frequent and important metabolic derangement that accompanies severe sepsis and septic shock. Matrix-Metalloproteinase 9 (MMP-9) has been shown to be elevated in acute stress hyperglycemia, chronic hyperglycemia, and in patient with sepsis. The objective of this study was to examine the clinical and pathogenic link between MMP-9 and blood glucose (BG) levels in patients with early severe sepsis and septic shock.

Methods

We prospectively examined 230 patients with severe sepsis and septic shock immediately upon hospital presentation and before any treatment including insulin administration. Clinical and laboratory data were obtained along with blood samples for the purpose of this study. Univariate tests for mean and median distribution using Spearman correlation and analysis of variance (ANOVA) were performed. A p value ≤ 0.05 was considered statistically significant.

Results

Patients were grouped based on their presenting BG level (mg/dL): BG <80 (n = 32), 80–120 (n = 53), 121–150 (n = 38), 151–200 (n = 23), and > 201 (n = 84). Rising MMP-9 levels were significantly associated with rising BG levels (p = 0.043). A corresponding increase in the prevalence of diabetes for each glucose grouping from 6.3 to 54.1 % (p = 0.0001) was also found. As MMP-9 levels increased a significantly (p < 0.001) decreases in IL-8 (pg/mL) and ICAM-1 (ng/mL) were noted.

Conclusion

This is the first study in humans demonstrating a significant and early association between MMP-9 and BG levels in in patients with severe sepsis and septic shock. Neutrophil affecting biomarkers such as IL-8 and ICAM-1 are noted to decrease as MMP-9 levels increase. Clinical risk stratification using MMP-9 levels could potentially help determine which patients would benefit from intensive versus conventional insulin therapy. In addition, antagonizing the up-regulation of MMP-9 could serve as a potential treatment option in severe sepsis or septic shock patients.

Matrix Metalloproteinases as Regulators of Vein Structure and Function: Implications in Chronic Venous Disease

Lower-extremity veins have efficient wall structure and function and competent valves that permit upward movement of deoxygenated blood toward the heart against hydrostatic venous pressure. Matrix metalloproteinases (MMPs) play an important role in maintaining vein wall structure and function. MMPs are zinc-binding endopeptidases secreted as inactive pro-MMPs by fibroblasts, vascular smooth muscle (VSM), and leukocytes. Pro-MMPs are activated by various activators including other MMPs and proteinases. MMPs cause degradation of extracellular matrix (ECM) proteins such as collagen and elastin, and could have additional effects on the endothelium, as well as VSM cell migration, proliferation, Ca(2+) signaling, and contraction. Increased lower-extremity hydrostatic venous pressure is thought to induce hypoxia-inducible factors and other MMP inducers/activators such as extracellular matrix metalloproteinase inducer, prostanoids, chymase, and hormones, leading to increased MMP expression/activity, ECM degradation, VSM relaxation, and venous dilation. Leukocyte infiltration and inflammation of the vein wall cause further increases in MMPs, vein wall dilation, valve degradation, and different clinical stages of chronic venous disease (CVD), including varicose veins (VVs). VVs are characterized by ECM imbalance, incompetent valves, venous reflux, wall dilation, and tortuosity. VVs often show increased MMP levels, but may show no change or decreased levels, depending on the VV region (atrophic regions with little ECM versus hypertrophic regions with abundant ECM) and MMP form (inactive pro-MMP versus active MMP). Management of VVs includes compression stockings, venotonics, and surgical obliteration or removal. Because these approaches do not treat the causes of VVs, alternative methods are being developed. In addition to endogenous tissue inhibitors of MMPs, synthetic MMP inhibitors have been developed, and their effects in the treatment of VVs need to be examined.

Role of the mevalonate pathway in specific CpG site demethylation on AGEs-induced MMP9 expression and activation in keratinocytes

BACKGROUND

Advanced glycation end products (AGEs) played an important role for the development of diabetic foot. In the present study we tried to show the mevalonate pathway and the key demethylation site(s) in the MMP-9 cis-promoter to the component of MMP-9 by AGEs in keratinocyte.

METHOD

Human keratinocyte cell line (HaCaT) cells were exposed to AGE-BSA. The plasmid construction and site-directed mutagenesis, dual-luciferase reporter assays, immunoblot, zymography, pull down, bisulfite sequencing PCR analysis and Western blotting were applied.

RESULTS

The AGE-BSA could increase and more activate the MMP9 in keratinocyte. The RhoA and ROCK1 also could be activated. These affects were blocked by the simvastatin. Meanwhile, the CpG site at -562 site was largely demethylated with AGE-BSA treatment. The cis-promoter sequences with -562 bp site methylated had a lower activity change, which had a highest expression activity and was decreased by simvastatin. Moreover, site-directed mutagenesis of CpG site (-562 bp) in the recombinant plasmid pCpGL-571 brought more reduction in activity, and the activity of methylated mutation pCpGL-571 remains decreased.

CONCLUSION

The cis-promoter regions of MMP9 would be methylated by AGE-BSA in keratinocyte through the mevalonate pathway, especially the -562 bp site.

Inhibition of class I histone deacetylase activity represses matrix metalloproteinase-2 and -9 expression and preserves LV function postmyocardial infarction

Left ventricular (LV) remodeling, after myocardial infarction (MI), can result in LV dilation and LV pump dysfunction. Post-MI induction of matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, have been implicated as causing deleterious effects on LV and extracellular matrix remodeling in the MI region and within the initially unaffected remote zone. Histone deacetylases (HDACs) are a class of enzymes that affect the transcriptional regulation of genes during pathological conditions. We assessed the efficacy of both class I/IIb- and class I-selective HDAC inhibitors on MMP-2 and MMP-9 abundance and determined if treatment resulted in the attenuation of adverse LV and extracellular matrix remodeling and improved LV pump function post-MI. MI was surgically induced in MMP-9 promoter reporter mice and randomized for treatment with a class I/IIb HDAC inhibitor for 7 days post-MI. After MI, LV dilation, LV pump dysfunction, and activation of the MMP-9 gene promoter were significantly attenuated in mice treated with either the class I/IIb HDAC inhibitor tichostatin A or suberanilohydroxamic acid (voronistat) compared with MI-only mice. Immunohistological staining and zymographic levels of MMP-2 and MMP-9 were reduced with either tichostatin A or suberanilohydroxamic acid treatment. Class I HDAC activity was dramatically increased post-MI. Treatment with the selective class I HDAC inhibitor PD-106 reduced post-MI levels of both MMP-2 and MMP-9 and attenuated LV dilation and LV pump dysfunction post-MI, similar to class I/IIb HDAC inhibition. Taken together, these unique findings demonstrate that selective inhibition of class I HDACs may provide a novel therapeutic means to attenuate adverse LV remodeling post-MI.

The lignan (+)-episesamin interferes with TNF-α-induced activation of VSMC via diminished activation of NF-ĸB, ERK1/2 and AKT and decreased activity of gelatinases

AIM

Activation of vascular smooth muscle cells (VSMC), a key event in the pathogenesis of atherosclerosis, is triggered by inflammatory stimuli such as tumour necrosis factor-alpha (TNF-α) causing a mitogenic VSMC response. The polyphenol (+)-episesamin (ES) was shown to counteract TNF-α-induced effects, for example in macrophages. Aiming for novel therapeutic options, we here investigated whether ES protects VSMC from TNF-α-induced growth and migration, which both contribute to the onset and progression of atherosclerosis.

METHODS

Human and murine VSMC were treated with combinations of ES and TNF-α. Expressions of mRNA were analyzed by RT-PCR. Enzymatic activities and proliferation were determined by specific substrate assays. Cell signalling was analyzed by Western blot and reporter gene assays. Migration was assessed by wound healing assays.

RESULTS

ES at 1-10 μm reduced basal and TNF-α-induced VSMC proliferation and migration due to impaired activation of extracellular signal-regulated kinases (ERK)1/2, Akt (protein kinase B), nuclear factor-kappa B (NF-ĸB) and vascular cell adhesion molecule (VCAM)-1. This was accompanied by reduced expression and secretion of matrix metalloproteinases (MMP)-2/-9, which are known to promote VSMC migration. Specific inhibitors of Akt, NF-ĸB and MMP-2/-9 reduced TNF-α-induced VSMC proliferation, confirming ES-specific effects. Besides, ES reduced TNF-α- and H₂O₂ -induced oxidative stress and in parallel induces anti-inflammatory haem oxygenase (HO)-1 expression.

CONCLUSION

ES interferes with inflammation-associated VSMC activation and subsequent decreased proliferation and migration due to anti-oxidative properties and impaired activation of NF-ĸB, known contributors to atherogenesis. These results suggest ES as a complemental treatment of VSMC specific vascular diseases such as atherosclerosis.

Deficiency of the protein-tyrosine phosphatase DEP-1/PTPRJ promotes matrix metalloproteinase-9 expression in meningioma cells

Brain-invasive growth of a subset of meningiomas is associated with less favorable prognosis. The molecular mechanisms causing invasiveness are only partially understood, however, the expression of matrix metalloproteinases (MMPs) has been identified as a contributing factor. We have previously found that loss of density enhanced phosphatase-1 (DEP-1, also designated PTPRJ), a transmembrane protein-tyrosine phosphatase, promotes meningioma cell motility and invasive growth in an orthotopic xenotransplantation model. We have now analyzed potential alterations of the expression of genes involved in motility control, caused by DEP-1 loss in meningioma cell lines. DEP-1 depleted cells exhibited increased expression of mRNA encoding MMP-9, and the growth factors EGF and FGF-2. The increase of MMP-9 expression in DEP-1 depleted cells was also readily detectable at the protein level by zymography. MMP-9 upregulation was sensitive to chemical inhibitors of growth factor signal transduction. Conversely, MMP-9 mRNA levels could be stimulated with growth factors (e.g. EGF) and inflammatory cytokines (e.g. TNFα). Increase of MMP-9 expression by DEP-1 depletion, or growth factor/cytokine stimulation qualitatively correlated with increased invasiveness in vitro scored as transmigration through matrigel-coated membranes. The studies suggest induction of MMP-9 expression promoted by DEP-1 deficiency, or potentially by growth factors and inflammatory cytokines, as a mechanism contributing to meningioma brain invasiveness.

Galangin and kaempferol suppress phorbol-12-myristate-13-acetate-induced matrix metalloproteinase-9 expression in human fibrosarcoma HT-1080 cells

Matrix metalloproteinase (MMP)-9 degrades type IV collagen in the basement membrane and plays crucial roles in several pathological implications, including tumorigenesis and inflammation. In this study, we analyzed the effect of flavonols on MMP-9 expression in phorbol-12-myristate-13-acetate (PMA)-induced human fibrosarcoma HT-1080 cells. Galangin and kaempferol efficiently decreased MMP-9 secretion, whereas fisetin only weakly decreased its secretion. Galangin and kaempferol did not affect cell viability at concentrations up to 30 μM. Luciferase reporter assays showed that galangin and kaempferol decrease transcription of MMP-9 mRNA. Moreover, galangin and kaempferol strongly reduce IκBα phosphorylation and significantly decrease JNK phosphorylation. These results indicate that galangin and kaempferol suppress PMA-induced MMP-9 expression by blocking activation of NF-κB and AP-1. Therefore, these flavonols could be used as chemopreventive agents to lower the risk of diseases involving MMP-9.

Physical influences of the extracellular environment on cell migration

The way in which a cell migrates is influenced by the physical properties of its surroundings, in particular the properties of the extracellular matrix. How the physical aspects of the cell's environment affect cell migration poses a considerable challenge when trying to understand migration in complex tissue environments and hinders the extrapolation of in vitro analyses to in vivo situations. A comprehensive understanding of these problems requires an integrated biochemical and biophysical approach. In this Review, we outline the findings that have emerged from approaches that span these disciplines, with a focus on actin-based cell migration in environments with different stiffness, dimensionality and geometry.

Suppression of PMA-induced tumor cell invasion and migration by ginsenoside Rg1 via the inhibition of NF-κB-dependent MMP-9 expression

Ginseng has become one of the most commonly used alternative herbal medicines, and its active component, ginsenoside Rg1 has known pharmacological effects, including anticancer properties. However, the effects of ginsenoside Rg1 on metastasis have yet to be investigated. In this study, we demonstrated the ability of ginsenoside Rg1 to suppress phorbol myristate acetate (PMA)-induced invasion and migration in MCF-7 breast cancer cells. MCF-7 cells were treated with ginsenoside Rg1 and incubated with or without PMA. The protein and mRNA expression of MMP-9 and MMP-2 was analyzed using Transwell and wound‑healing assays and western blotting. The results showed that suppression was associated with the reduced secretion of MMP-9, a key metastatic enzyme. MMP-9 levels were regulated transcriptionally and correlated with the suppression of NF-κB phosphorylation and DNA binding activity. Conversely, ginsenoside Rg1 did not affect MMP-2 mRNA and TIMP-1 mRNA levels, or the activation of AP-1, suggesting a specificity of pathway inhibition. Inhibition of NF‑κB activation by p65 small‑interfering RNA (siRNA) was shown to suppress PMA-induced cell invasion and migration. The siRNA studies also showed that PMA-induced MMP-9 expression is NF-κB-dependent. The results suggested that the anticancer properties of ginsenoside Rg1 may derive from its ability to inhibit invasion and migration, and that these processes are regulated in breast cancer cells through the NF-κB‑mediated regulation of MMP-9 expression.

WAVE3-NFκB interplay is essential for the survival and invasion of cancer cells

The WAVE3 cytoskeletal protein promotes cancer invasion and metastasis. We have shown that the WAVE3-mediated activation of cancer cell invasion is due, in part, to its regulation of expression and activity of key metalloproteinases (MMPs), including MMP9, which is centrally involved in invadopodia-mediated degradation of the extracellular matrix (ECM). MMP9 is also a major NFκB target gene, suggesting a potential linkage of WAVE3 to this pathway, which we sought to investigate. Mechanistically, we found that loss of WAVE3 in cancer cells leads to inhibition of NFκB signaling as a result of a decrease in the nuclear translocation of NFκB and therefore loss of activation of NFκB target genes. Conversely, overexpression of WAVE3 was sufficient to enhance NFκB activity. Both pharmacologic and genetic manipulations of NFκB effector molecules show that the biological consequence of loss of WAVE3 function in the NFκB pathway result the inhibition of invadopodia formation and ECM degradation by cancer cells, and these changes are a consequence of decreased MMP9 expression and activity. Loss of WAVE3 also sensitized cancer cells to apoptosis and cell death driven by TNFα, through the inhibition of the AKT pro-survival pathway. Our results identify a novel function of WAVE3 in NFκB signaling, where its activity is essential for the regulation of invadopodia and ECM degradation. Therefore, targeted therapeutic inhibition of WAVE3 will sensitize cancer cells to apoptosis and cell death, and suppress cancer invasion and metastasis.

Sphingosine-1-phosphate mediates a reciprocal signaling pathway between stellate cells and cancer cells that promotes pancreatic cancer growth

Sphingosine-1-phosphate (S1P) is produced by sphingosine kinase 1 and is implicated in tumor growth, although the mechanisms remain incompletely understood. Pancreatic stellate cells (PSCs) reside within the tumor microenvironment and may regulate tumor progression. We hypothesized that S1P activates PSCs to release paracrine factors, which, in turn, increase cancer cell invasion and growth. We used a combination of human tissue, in vitro, and in vivo studies to mechanistically evaluate this concept. Sphingosine kinase 1 was overexpressed in human pancreatic tissue, especially within tumor cells. S1P activated PSCs in vitro and conditioned medium from S1P-stimulated PSCs, increased pancreatic cancer cell migration, and invasion, which was dependent on S1P2, ABL1 (alias c-Abl) kinase, and matrix metalloproteinase-9. In vivo studies showed that pancreatic cancer cells co-implanted with S1P2 receptor knockdown PSCs led to less cancer growth and metastasis in s.c. and orthotopic pancreatic cancer models compared with control PSCs. Pancreatic cancer cell-derived S1P activates PSCs to release paracrine factors, including matrix metalloproteinase-9, which reciprocally promotes tumor cell migration and invasion in vitro and cancer growth in vivo.

c-Src-dependent transactivation of PDGFR contributes to TNF-α-induced MMP-9 expression and functional impairment in osteoblasts

Matrix metalloproteinases (MMPs), MMP-9 especially, have been shown to be induced by cytokines, including tumor necrosis factor-α (TNF-α) and may contribute to bone inflammatory diseases and postnatal bone modeling and remodeling. However, the mechanisms underlying MMP-9 expression induced by TNF-α in osteoblasts remain unclear. Here, we showed that in MC3T3-E1 cells, TNF-α induced MMP-9 gene expression determined by real-time PCR, zymography, and promoter assay. TNF-α-mediated responses were attenuated by pretreatment with the inhibitor of protein tyrosine kinase (PTK; genistein), c-Src (PP1), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), or AP-1 (Tanshinone IIA) and transfection with siRNA of c-Src, PDGFR, p85, Akt, c-Jun, or ATF2. Moreover, TNF-α also time-dependently stimulated phosphorylation of c-Src and PDGFR and c-Src/PDGFR complex formation, which were reduced by pretreatment with PP1 or AG1296. TNF-α-stimulated Akt phosphorylation was inhibited by genistein, PP1, AG1296, LY294002, or SH5. We further demonstrated that TNF-α stimulated ERK1/2, p38 MAPK, and JNK1/2 phosphorylation via a c-Src-dependent PDGFR/PI3K/Akt pathway. TNF-α stimulated AP-1 activation, including c-Jun and ATF2 phosphorylation and AP-1 transcription activity via MAPK-dependent pathways. In addition, TNF-α-induced MMP-9 promoter activity was mediated through an AP-1 binding domain of the MMP-9 promoter region. Finally, we found that up-regulation of MMP-9 contributes to MMP-mediated type I collagen degradation and osteoblasts detachment. These results suggested that TNF-α-induced MMP-9 expression is mediated through a c-Src-dependent PDGFR transactivation and PI3K/Akt cascade linking to MAPK-mediated activation of AP-1 (c-Jun/ATF2) and leading to functional impairment in osteoblasts.

p27KIP1 is involved in ERK1/2-mediated MMP-9 expression via the activation of NF-κB binding in the IL-7-induced migration and invasion of 5637 cells

Interleukin-7 (IL-7) plays a pivotal role in the development and survival of lymphocytes, but its role in cancer cell responses remains unexplained. In this study, IL-7 treatment resulted in a significant induction in the wound-healing migration and Matrigel invasion of the 5637 bladder cancer cells, but it did not result in cell proliferation. In addition, IL-7 treatment strongly induced MMP-9 expression, and increased the binding activation of NF-κB and AP-1 motifs, the important transcription factors that regulate MMP-9 expression. Moreover, the treatment of 5637 cells with IL-7 stimulated the phosphorylation of ERK1/2. U0126, an ERK1/2-specific inhibitor, blocked IL-7-induced cell migration and invasion, and also suppressed the expression of MMP-9 in the presence of IL-7. Inhibition of the ERK1/2 function consistently reversed the binding activity of NF-κB without altering AP-1 activation in IL-7-stimulated cells. Among the cell cycle regulators examined, only the expression of the cell cycle inhibitor p27KIP1 was induced by IL-7. Moreover, the inhibition of p27KIP1 by small interfering RNA (siRNA) abolished the migration, invasion and phosphorylation of ERK1/2, the expression of MMP-9, and the binding activity of the NF-κB motif in IL-7-stimulated 5637 cells. These results demonstrated that the cell cycle inhibitor p27KIP1 is involved in ERK1/2-mediated MMP-9 expression via activation of the NF-κB binding motif, which leads to the migration and invasion of bladder cancer cells induced by IL-7. These novel results could help explain the migration and invasion of bladder tumor cells.

Gelatinase B/MMP-9 in Tumour Pathogenesis and Progression

Since its original identification as a leukocyte gelatinase/type V collagenase and tumour type IV collagenase, gelatinase B/matrix metalloproteinase (MMP)-9 is now recognised as playing a central role in many aspects of tumour progression. In this review, we relate current concepts concerning the many ways in which gelatinase B/MMP-9 influences tumour biology. Following a brief outline of the gelatinase B/MMP-9 gene and protein, we analyse the role(s) of gelatinase B/MMP-9 in different phases of the tumorigenic process, and compare the importance of gelatinase B/MMP-9 source in the carcinogenic process. What becomes apparent is the importance of inflammatory cell-derived gelatinase B/MMP-9 in tumour promotion, early progression and triggering of the "angiogenic switch", the integral relationship between inflammatory, stromal and tumour components with respect to gelatinase B/MMP-9 production and activation, and the fundamental role for gelatinase B/MMP-9 in the formation and maintenance of tumour stem cell and metastatic niches. It is also apparent that gelatinase B/MMP-9 plays important tumour suppressing functions, producing endogenous angiogenesis inhibitors, promoting inflammatory anti-tumour activity, and inducing apoptosis. The fundamental roles of gelatinase B/MMP-9 in cancer biology underpins the need for specific therapeutic inhibitors of gelatinase B/MMP-9 function, the use of which must take into account and substitute for tumour-suppressing gelatinase B/MMP-9 activity and also limit inhibition of physiological gelatinase B/MMP-9 function.

Src plays a key role in ADAM28 expression in v-src-transformed epithelial cells and human carcinoma cells

ADAM28, a disintegrin and metalloproteinase 28, is overexpressed by carcinoma cells with direct correlations with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, the molecular mechanisms of ADAM28 gene expression in carcinoma cells remain elusive. Herein, we investigated the expression of ADAM28 in Madin-Darby canine kidney epithelial cells transformed by oncogenes, including v-src, LMP1, ErbB2, Ha-Ras, and c-Fos, and found that v-src transformants selectively induce ADAM28. Implantation of the v-src transformants showed a progressively growing tumor, which was significantly suppressed by local injections of anti-ADAM28 antibody. ADAM28 expression in v-src transformants was partially inhibited by treatment with inhibitors to Src kinase, mitogen-activated protein kinase kinase (MEK), phosphatidylinositol 3-kinase (PI3K), or mammalian target of rapamycin, and abrogated by v-Src kinase inhibitor, radicicol, or a mixture of MEK and PI3K inhibitors. Human carcinoma cell lines of the lung, breast, ovary, kidney, and colon showed ADAM28 expression, which was correlated with phosphorylation of c-Src and suppressed by the inhibitors in a similar way to v-src transformants. IHC of the human tumor tissues demonstrated co-expression of ADAM28 and phosphorylated Src in neoplastic cells of the breast, lung, and colon carcinomas and some adenomas of the colon, but not in nonneoplastic colon mucosa. Our data provide, to the best of our knowledge, the first evidence that Src is an inducer of ADAM28 gene expression through the MEK/extracellular signal-regulated kinase and PI3K/mammalian target of rapamycin pathways.

Matrix metalloproteinase (MMP) 9 transcription in mouse brain induced by fear learning

Memory formation requires learning-based molecular and structural changes in neurons, whereas matrix metalloproteinase (MMP) 9 is involved in the synaptic plasticity by cleaving extracellular matrix proteins and, thus, is associated with learning processes in the mammalian brain. Because the mechanisms of MMP-9 transcription in the brain are poorly understood, this study aimed to elucidate regulation of MMP-9 gene expression in the mouse brain after fear learning. We show here that contextual fear conditioning markedly increases MMP-9 transcription, followed by enhanced enzymatic levels in the three major brain structures implicated in fear learning, i.e. the amygdala, hippocampus, and prefrontal cortex. To reveal the role of AP-1 transcription factor in MMP-9 gene expression, we have used reporter gene constructs with specifically mutated AP-1 gene promoter sites. The constructs were introduced into the medial prefrontal cortex of neonatal mouse pups by electroporation, and the regulation of MMP-9 transcription was studied after contextual fear conditioning in the adult animals. Specifically, -42/-50- and -478/-486-bp AP-1 binding motifs of the mouse MMP-9 promoter sequence have been found to play a major role in MMP-9 gene activation. Furthermore, increases in MMP-9 gene promoter binding by the AP-1 transcription factor proteins c-Fos and c-Jun have been demonstrated in all three brain structures under investigation. Hence, our results suggest that AP-1 acts as a positive regulator of MMP-9 transcription in the brain following fear learning.

Regulation of matrix metalloproteinase-9 by epigenetic modifications and the development of diabetic retinopathy

Diabetes activates retinal matrix metalloproteinase-9 (MMP-9), and MMP-9 damages the mitochondria and augments capillary cell apoptosis. Our aim is to elucidate the mechanism responsible for MMP-9 activation. Histone modifications and recruitment of the nuclear transcriptional factor-κB (p65 subunit) at the MMP-9 promoter and the activity of lysine-specific demethylase 1 (LSD1) were measured in the retina from streptozotocin-induced diabetic rats. The role of LSD1 in MMP-9 activation was investigated in isolated retinal endothelial cells transfected with LSD1 small interfering RNA (siRNA). The results were confirmed in the retina from human donors with diabetic retinopathy. Diabetes decreased histone H3 dimethyl lysine 9 (H3K9me2) and increased acetyl H3K9 (Ac-H3K9) and p65 at the retinal MMP-9 promoter. LSD1 enzyme activity and its transcripts were elevated. LSD1 siRNA ameliorated the glucose-induced decrease in H3K9me2 and increase in p65 at the MMP-9 promoter, and prevented MMP-9 activation, mitochondrial damage, and cell apoptosis. Human donors with diabetic retinopathy had similar epigenetic changes at the MMP-9 promoter. Thus, activated LSD1 hypomethylates H3K9 at the MMP-9 promoter and this frees up that lysine 9 for acetylation. Increased Ac-H3K9 facilitates the recruitment of p65, resulting in MMP-9 activation and mitochondrial damage. Thus, the regulation of LSD1 by molecular or pharmacological means has the potential to retard the development of diabetic retinopathy.

Interleukin-5 enhances the migration and invasion of bladder cancer cells via ERK1/2-mediated MMP-9/NF-κB/AP-1 pathway: involvement of the p21WAF1 expression

Inflammatory cytokines may be a critical component of epithelial cancer progression. We examined the role of interleukin (IL)-5 in the migration of bladder cancer cells. The expression of IL-5 and its receptor IL-5Rα was enhanced in patients with muscle invasive bladder cancers (MIBC), and then it was detected in bladder cancer cell lines 5637 and T-24. IL-5 increased migration and MMP-9 expression via activation of transcription factors NF-κB and AP-1, and induced activation of ERK1/2 and Jak-Stat signaling in both cells. Treatment with ERK1/2 inhibitor U0126 significantly inhibited induction of migration, MMP-9 expression, and activation of NF-κB and AP-1 in IL-5-treated cells. However, none of the Jak inhibitors affected the IL-5-induced migration of bladder cancer cells. Moreover, gene knockdown for IL-5Rα, using siRNA transfection, suppressed migration, ERK1/2 activation, MMP-9 expression, as well as the binding activation of NF-κB and AP-1 in IL-5-treated bladder cancer cells. Similar results were observed in βc siRNA (si-βc) transfected cells. Unexpectedly, IL-5 treatment resulted in significant induction of p21WAF1 in both cell lines. The p21WAF1-specific small interfering RNA inhibited IL-5-induced cell migration, ERK activity, MMP-9 expression, and activation of NF-κB and AP-1 in bladder cancer cells. The effects of IL-5-induced cell responses were confirmed by transfection of IL-5 gene, which demonstrated that p21WAF1 participates in the induction of cell migration, leading to an increase in ERK1/2-mediated MMP-9 expression through activation of NF-κB and AP-1 in IL-5-treated bladder cancer cells. These unexpected results provide a theoretical basis for the therapeutic targeting of IL-5 in bladder cancer.

Human parvovirus B19 NS1 protein aggravates liver injury in NZB/W F1 mice

Human parvovirus B19 (B19) has been associated with a variety of diseases. However, the influence of B19 viral proteins on hepatic injury in SLE is still obscure. To elucidate the effects of B19 viral proteins on livers in SLE, recombinant B19 NS1, VP1u or VP2 proteins were injected subcutaneously into NZB/W F1 mice, respectively. Significant expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected in NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Markedly hepatocyte disarray and lymphocyte infiltration were observed in livers from NZB/WF 1 mice receiving B19 NS1 as compared to those mice receiving PBS. Additionally, significant increases of Tumor Necrosis Factor -α (TNF-α), TNF-α receptor, IκB kinase -α (IKK-α), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IκB) and nuclear factor-kappa B (NF-κB) were detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Accordingly, significant increases of matrix metalloproteinase-9 (MMP9) and U-plasminogen activator (uPA) were also detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Contrarily, no significant variation on livers from NZB/W F1 mice receiving B19 VP1u or VP2 was observed as compared to those mice receiving PBS. These findings firstly demonstrated the aggravated effects of B19 NS1 but not VP1u or VP2 protein on hepatic injury and provide a clue in understanding the role of B19 NS1 on hepatic injury in SLE.

Suppressive effects of an ethanol extract of Gleditsia sinensis thorns on human SNU-5 gastric cancer cells

The thorns of Gleditsia sinensis are a traditional Oriental medicine used for the treatment of swelling, suppuration, carbuncle and skin diseases. In the present study, we identified a novel molecular mechanism by which an ethanol extract of Gleditsia sinensis thorns (EEGS) inhibits the growth of the SNU-5 human gastric cancer cell line. EEGS treatment inhibited cell growth and was associated with G1 phase cell cycle arrest at a concentration of 400 µg/ml (IC50) in SNU-5 cells. Treatment with EEGS also stimulated p21WAF1 expression, which significantly decreased the expression of cyclins and cyclin-dependent kinases (CDKs). Further study suggested that p38 MAP kinase pathways may be involved in the inhibition of cell proliferation through p21WAF1‑dependent G1 phase cell cycle arrest in EEGS-treated cells. In addition, NF-κB and AP-1 transcription factor binding sites were identified as the cis-elements for tumor necrosis factor-α (TNF-α)-induced matrix metalloproteinase-9 (MMP-9) expression in SNU-5 cells, as determined by gel-shift assay. Treatment of cells with EEGS suppressed MMP-9 expression induced by TNF-α via a decrease in the binding activity of both NF-κB and AP-1 motifs. These data demonstrate that EEGS-mediated inhibition of cell growth appears to involve the activation of p38 MAP kinase, subsequently leading to the induction of p21WAF1 and the downregulation of cyclin D1/CDK4 and cyclin E/CDK2 complexes. Moreover, EEGS strongly inhibited TNF-α-induced MMP-9 expression by impeding the DNA binding activity of NF-κB and AP-1. Overall, these results provide a potential mechanism for EEGS in the treatment of gastric cancer.

Interleukin-20 promotes migration of bladder cancer cells through extracellular signal-regulated kinase (ERK)-mediated MMP-9 protein expression leading to nuclear factor (NF-κB) activation by inducing the up-regulation of p21(WAF1) protein expression

The role of inflammatory cytokine interleukin-20 (IL-20) has not yet been studied in cancer biology. Here, we demonstrated up-regulation of both IL-20 and IL-20R1 in muscle-invasive bladder cancer patients. The expressions of IL-20 and IL-20R1 were observed in bladder cancer 5637 and T-24 cells. We found that IL-20 significantly increased the expression of matrix metalloproteinase (MMP)-9 via binding activity of NF-κB and AP-1 in bladder cancer cells and stimulated the activation of ERK1/2, JNK, p38 MAPK, and JAK-STAT signaling. Among the pathways examined, only ERK1/2 inhibitor U0126 significantly inhibited IL-20-induced migration and invasion. Moreover, siRNA knockdown of IL-20R1 suppressed migration, invasion, ERK1/2 activation, and NF-κB-mediated MMP-9 expression induced by IL-20. Unexpectedly, the cell cycle inhibitor p21(WAF1) was induced by IL-20 treatment without altering cell cycle progression. Blockade of p21(WAF1) function by siRNA reversed migration, invasion, activation of ERK signaling, MMP-9 expression, and activation of NF-κB in IL-20-treated cells. In addition, IL-20 induced the activation of IκB kinase, the degradation and phosphorylation of IκBα, and NF-κB p65 nuclear translocation, which was regulated by ERK1/2. IL-20 stimulated the recruitment of p65 to the MMP-9 promoter region. Finally, the IL-20-induced migration and invasion of cells was confirmed by IL-20 gene transfection and by addition of anti-IL-20 antibody. This is the first report that p21(WAF1) is involved in ERK1/2-mediated MMP-9 expression via increased binding activity of NF-κB, which resulted in the induction of migration in IL-20/IL-20R1 dyad-induced bladder cancer cells. These unexpected results might provide a critical new target for the treatment of bladder cancer.

Relaxin induces matrix-metalloproteinases-9 and -13 via RXFP1: induction of MMP-9 involves the PI3K, ERK, Akt and PKC-ζ pathways

We determined the precise role of relaxin family peptide (RXFP) receptors-1 and -2 in the regulation of MMP-9 and -13 by relaxin, and delineated the signaling cascade that contributes to relaxin's modulation of MMP-9 in fibrocartilaginous cells. Relaxin treatment of cells in which RXFP1 was silenced resulted in diminished induction of MMP-9 and -13 by relaxin, whereas overexpression of RXFP1 potentiated the relaxin-induced expression of these proteinases. Suppression or overexpression of RXFP2 resulted in no changes in the relaxin-induced MMP-9 and -13. Studies using chemical inhibitors and siRNAs to signaling molecules showed that PI3K, Akt, ERK and PKC-ζ and the transcription factors Elk-1, c-fos and, to a lesser extent, NF-κB are involved in relaxin's induction of MMP-9. Our findings provide the first characterization of signaling cascade involved in the regulation of any MMP by relaxin and offer mechanistic insights on how relaxin likely mediates extracellular matrix turnover.

The relationship between the MMP system, adrenoceptors and phosphoprotein phosphatases

The MMPs and their inhibitors [tissue inhibitor of MMPs (TIMPs)] form the mainstay of extracellular matrix homeostasis. They are expressed in response to numerous stimuli including cytokines and GPCR activation. This review highlights the importance of adrenoceptors and phosphoprotein phosphatases (PPP) in regulating MMPs in the cardiovascular system, which may help explain some of the beneficial effects of targeting the adrenoceptor system in tissue remodelling and will establish emerging crosstalk between these three systems. Although α- and β-adrenoceptor activation increases MMP but decreases TIMP expression, MMPs are implicated in the growth stimulatory effects of adrenoceptor activation through transactivation of epidermal growth factor receptor. Furthermore, they have recently been found to catalyse the proteolysis of β-adrenoceptors and modulate vascular tone. While the mechanisms underpinning these effects are not well defined, reversible protein phosphorylation by kinases and phosphatases may be key. In particular, PPP (Ser/Thr phosphatases) are not only critical in resensitization and internalization of adrenoceptors but also modulate MMP expression. The interrelationship is complex as isoprenaline (ISO) inhibits okadaic acid [phosphoprotein phosphatase type 1/phosphoprotein phosphatase type 2A (PP2A) inhibitor]-mediated MMP expression. While this may be simply due to its ability to transiently increase PP2A activity, there is evidence for MMP-9 that ISO prevents okadaic acid-mediated expression of MMP-9 through a β-arrestin, NF-κB-dependent pathway, which is abolished by knock-down of PP2A. It is essential that crosstalk between MMPs, adrenoceptors and PPP are investigated further as it will provide important insight into how adrenoceptors modulate cardiovascular remodelling, and may identify new targets for pharmacological manipulation of the MMP system.

Identification of pro-inflammatory cytokines associated with muscle invasive bladder cancer; the roles of IL-5, IL-20, and IL-28A

We used gene expression profiling to identify inflammatory cytokines that correlate with bladder cancer development. Gene expression profiles of the tissue samples were investigated using cDNA microarrays that contained 103 non-muscle invasive bladder cancers (NMIBC), 62 muscle invasive bladder cancers (MIBC), 58 samples of histologically normal-looking surrounding tissues, and 10 normal, healthy subjects who served as the control cohort for comparison. We grouped the data-sets according to biological characterizations and focused on immune response genes with at least 2-fold differential expression in MIBC vs. controls. The experimental data-set identified 36 immune-related genes that were significantly altered in MIBC samples. In addition, 10 genes were up-regulated and 26 genes were down-regulated in MIBC samples compared with the normal tissues. Among the 10 up-regulated molecules examined, the capacity for both wound-healing migration and invasion was enhanced in response to IL-5, IL-20, and IL-28A in bladder cancer cell lines (253J and EJ cells), compared with untreated cells. The expression levels of IL-5, IL-20, and IL-28A were increased in patients with MIBC. All 3 cytokines and their receptors were produced in bladder cancer cell lines, as determined by real-time PCR, immunoblot analysis and confocal immunofluorescence. Up-regulation of MMP-2 and MMP-9 was found after IL-5, IL-20, and IL-28A stimulation in both cell types. Moreover, an EMSA assay showed that treatment with IL-5, IL-20, and IL-28A induced activation of the transcription factors NF-κB and AP-1 that regulate the MMP-9 promoter. Finally, activation of MAPK and Jak-Stat signaling was observed after the addition of IL-5, IL-20, and IL-28A to bladder cancer cells. This study suggests the presence of specific inflammatory cytokine (IL-5, IL-20, and IL-28A)-mediated association in bladder cancer development. All 3 cytokines may be important new molecular targets for the modulation of migration and invasion in bladder cancer.

Interleukin-28A triggers wound healing migration of bladder cancer cells via NF-κB-mediated MMP-9 expression inducing the MAPK pathway

Interleukin (IL)-28A, also called IFN-λ2, is a member of the classIIcytokine family and has demonstrated anti-proliferative and anti-viral signals. The present study demonstrated migration inducement of IL-28A-treated bladder cancer cells - a novel function. RNA microarray analysis showed an enhanced expression of IL-28A and its receptor IL-28AR1 in muscle invasive urothelial carcinoma in a human bladder. Strong expression of IL-28A and IL-28AR1 was detected in bladder cancer tissues and cell lines (5637, T-24, and HT1376 cells), as determined by real-time PCR and immunoblot analysis. IL-28A treatment induced migration of bladder cancer cells, independent of the cell growth. IL-28AR1-specific small interfering RNA (si-IL-28AR1) inhibited the induction of migration in IL-28A-treated cells. IL-28A treatment stimulated the expression of matrix metalloproteinases-9 (MMP-9) via activation of transcription factor NF-κB. Gene knockdown for MMP-9 and the p65 subunit of NF-κB, using siRNA transfection, suppressed wound healing migration in IL-28A-treated bladder cancer cells. Also, treatment with IL-28A induced activation of mitogen-activated protein kinase (MAPK) in bladder cancer cells. MAPK function blockage by a MAPK-specific inhibitor showed that MAPK phosphorylation is required for IL-28A-induced MMP-9 expression through activation of NF-κB. The transient transfection of bladder cancer cells with ERK1/2 knock down (si-ERK1/2) and dominant negative p38 (DNp38) suppressed IL-28A-induced migration. IL-28A-induced induction of MMP-9 expression, MAPK activation, and DNA binding activity of NF-κB was abolished in the presence of IL-28A neutralizing antibody or by transfection of si-IL-28AR1. These results show that IL-28A/IL-28AR1 dyad-induced wound healing migration requires NF-κB-mediated MMP-9 expression by MAPK activation.

Okadaic acid induces matrix metalloproteinase-9 expression in fibroblasts: crosstalk between protein phosphatase inhibition and β-adrenoceptor signalling

BACKGROUND AND PURPOSE

Interactions between protein phosphatase inhibition and matrix metalloproteinase (MMP)-9 expression have implications for tissue remodelling after injury. Stimulation of β-adrenoceptors could affect such interactions as isoprenaline increases protein phosphatase 2A (PP2A) activity and MMP-9 abundance. We investigated the effect of okadaic acid (OA) on MMP-9 expression to assess interactions between phosphatase inhibition and β-adrenoceptor signalling in fibroblasts.

EXPERIMENTAL APPROACH

Fibroblasts were exposed to OA alone and in combination with isoprenaline. Effects on MMP-9 expression and intracellular signalling were studied using promoter assays, Western blot analysis and siRNA methodologies.

KEY RESULTS

Okadaic acid increased MMP-9 abundance in human cardiac ventricular fibroblasts, NIH3T3 fibroblasts and hepatic stellate cells. This effect was unaffected by PP2A knockdown in NIH3T3 cells. OA increased phosphorylation of NF-κB, but not NF-κB promoter activity, IκBα degradation, or nuclear translocation of p65-NF-κB. Exposure to SB202190 (p38 MAPK), U0126 (ERK1/2) and NF-κB III inhibitor revealed that OA induced MMP-9 activity through p38 MAPK. Isoprenaline inhibited OA-mediated MMP-9 expression in NIH3T3, in a β-arrestin 2- and PP2A-dependent manner. Mutation of the activator protein-1 (AP-1) and NF-κB binding sites demonstrated that OA-induced MMP-9 activity was mediated through the AP-1 but not NF-κB sites. The latter mediated the inhibitory effect of isoprenaline on OA-induced MMP-9 promoter activity.

CONCLUSION AND IMPLICATIONS

Okadaic acid induced MMP-9 activity through p38 MAPK and was inhibited by isoprenaline via a pathway involving β-arrestin 2, PP2A and an NF-κB binding motif. These findings elucidate how phosphoprotein phosphatases and adrenoceptors may modulate tissue remodelling by affecting fibroblast function.

Epstein-Barr virus latent membrane protein 2A promotes invasion of nasopharyngeal carcinoma cells through ERK/Fra-1-mediated induction of matrix metalloproteinase 9

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) is highly metastatic, and this malignant feature may be promoted by an EBV oncoprotein, latent membrane protein 2A (LMP2A). Acting as a signal regulator, LMP2A can enhance invasiveness and motility of epithelial cells. Downstream from the LMP2A-triggered signaling events, it is largely unknown what key effector proteins are induced and essentially promote cell invasion. In the present study, we found that in NPC cells, LMP2A upregulated matrix metalloproteinase 9 (MMP9), a metastasis-associated protease. LMP2A increased MMP9 expression at both the mRNA and protein levels. It also activated the MMP9 promoter, in which two AP-1 elements were required for the promoter activation. Among AP-1 transcription factors, Fra-1 was induced by LMP2A and is essential for LMP2A-triggered MMP9 expression. Induction of Fra-1 was dependent on the LMP2A-activated ERK1/2 pathway, and induction of the ERK1/2-Fra-1-MMP9 axis required PY motifs in the amino-terminal domain of LMP2A. Notably, LMP2A-promoted invasion of NPC cells was blocked when MMP9 expression, Fra-1 induction, or ERK1/2 activation was inhibited. In addition, we found an association of LMP2A with MMP9 expression in NPC tumor biopsy specimens, where Fra-1 was a major mediation factor. This study reveals an underlying mechanism of LMP2A-induced cell invasion, from signal transduction to upregulation of a critical protease. Considering that MMP9 can also be upregulated by another EBV oncoprotein, LMP1, this protease may be a pivotal effector at which the EBV-induced, invasion-promoting mechanisms converge, serving as an attractive therapeutic target for NPC treatment.

Inhibitive effect of triptolide on invasiveness of human fibrosarcoma cells by downregulating matrix metalloproteinase-9 expression

OBJECTIVE

To explore the molecular mechanisms of antitumor properties of triptolide, a bioactive component isolated from the Chinese herb Tripterygium wolfordii Hook F.

METHODS

Human fibrosarcoma HT-1080 cells were treated with different doses of triptolide for 72 h. Then the expression and activity of matrix metalloproteinase (MMP)-2 and -9 were measured and the invasiveness of triptolide-treated HT-1080 cells was compared with that of anti-MMP-9-treated HT-1080 cells.

RESULTS

18 nmol/L triptolide inhibited the gene expression and activity of MMP-9, but not those of MMP-2, in HT-1080 cells. In addition, both 18 nmol/L triptolide and 3 μg/mL anti-MMP-9 significantly reduced the invasive potential of HT-1080 cells, by about 50% and 35%, respectively, compared with the control. Whereas there was no significant difference between the effect of 18 nmol/L triptolide and that of anti-MMP-9 on invasive potential of HT-1080 cells.

CONCLUSIONS

These data suggest that triptolide inhibits tumor cell invasion partly by reducing MMP-9 gene expression and activity.

Prostaglandin E2 induces matrix metalloproteinase 9 expression in dendritic cells through two independent signaling pathways leading to activator protein 1 (AP-1) activation

Dendritic Cells (DCs) play an important role in the initiation of the immune response by migrating to regional lymph nodes and presenting antigen processed at the inflammatory site to antigen-specific naïve T cells. Prostaglandin E2 (PGE2) has been reported to play an essential role in DC migration. We reported previously that PGE2 induces matrix metalloproteinase 9 (MMP-9) expression in DCs and that PGE2-induced MMP-9 is required for DC migration in vivo and in vitro. In this study, we investigated the signaling mechanisms involved in PGE2-induced MMP-9 expression in DCs. We show that PGE2-induced MMP-9 expression is mediated primarily through the EP2/EP4 → cAMP → protein kinase A (PKA)/PI3K → ERK signaling pathway, leading to c-Fos expression, and through JNK-mediated activation of c-Jun in a PKA/PI3K/ERK-independent manner. EP2 and EP4 receptor agonists, as well as cAMP analogs, mimic the up-regulation of MMP-9 by PGE2. PKA, PI3K, and ERK inhibitors abolished PGE2- and cAMP-induced c-Fos and MMP-9 up-regulation, and ERK activation was required for the binding of activator protein 1 (AP-1) transcription factor to the MMP-9 promoter. Our results describe a new molecular mechanism for the effect of PGE2 on MMP-9 production in DCs that could lead to future therapeutic approaches using ERK inhibitors to regulate DC migration.

Upregulation of equine matrix metalloproteinase 1 by bovine papillomavirus type 1 is through the transcription factor activator protein-1

Equine sarcoids represent the most common skin tumours in equids worldwide, characterized by extensive invasion and infiltration of lymphatics, rare regression and high recurrence after surgical intervention. Bovine papillomavirus type 1 (BPV-1) activity is necessary for the transformation phenotype of equine fibroblasts. Among the many changes induced by BPV-1, matrix metalloproteinase 1 (MMP-1) upregulation contributes to the invasiveness of equine fibroblasts. However, it is not yet known how BPV-1 proteins regulate equine MMP-1 expression. To elucidate this mechanism, the equine MMP-1 promoter was cloned and analysed. A putative activator protein-1 (AP-1)-binding site was demonstrated to be crucial for upregulated MMP-1 promoter activity by BPV-1. BPV-1 E6 and E7 proteins increased MMP-1 promoter activity, and inhibition of BPV-1 gene expression by small interfering RNA significantly reduced the promoter activity. c-Jun and Fra-1, two components of the AP-1 transcription factor complex, were overexpressed and activated by BPV-1 in equine fibroblasts. Finally, BPV-1 E5, E6 and E7 proteins increased MMP-1 mRNA and protein expression. In conclusion, the expression of MMP-1 can be enhanced by BPV-1 oncoproteins E6 and E7 through the AP-1 transcription factor and by E5 via an indirect mechanism. These findings shed light on the mechanism of BPV-1-mediated equine fibroblast infiltration and indicate that both BPV-1 oncoproteins and AP-1 could be potential targets for equine sarcoid therapy.

Caffeic acid phenethyl ester inhibits invasion and expression of matrix metalloproteinase in SK-Hep1 human hepatocellular carcinoma cells by targeting nuclear factor kappa B

Numerous studies have shown that the levels of matrix metalloproteinase (MMP)-2 and/or MMP-9 are associated with the invasive phenotypes of cancer cells. This study investigated the effects of caffeic acid phenethyl ester (CAPE), a chemopreventive phytochemical derived from honeybee propolis, on the invasive phenotype of SK-Hep1 human hepatocellular carcinoma cells (SK-Hep1 cells). CAPE effectively suppressed SK-Hep1 cell invasion in a dose-dependent manner. The constitutive expression of MMP-2 and MMP-9 in SK-Hep1 cells was almost completely abolished by treatment with 12.5 muM CAPE. CAPE also significantly inhibited nuclear factor kappa B (NF-kappaB) DNA-binding activity in SK-Hep1 cells. These results taken together suggest that CAPE exerts antimetastatic potential through inhibition of MMP-2 and MMP-9 expression, possibly by targeting NF-kappaB in hepatocellular carcinoma.

Nimbolide retards tumor cell migration, invasion, and angiogenesis by downregulating MMP-2/9 expression via inhibiting ERK1/2 and reducing DNA-binding activity of NF-κB in colon cancer cells

Nimbolide, a plant-derived limonoid has been shown to exert its antiproliferative effects in various cell lines. We demonstrate that nimbolide effectively inhibited proliferation of WiDr colon cancer cells through inhibition of cyclin A leading to S phase arrest. It also caused activation of caspase-mediated apoptosis through the inhibition of ERK1/2 and activation of p38 and JNK1/2. Further nimbolide effectively retarded tumor cell migration and invasion through inhibition of metalloproteinase-2/9 (MMP-2/9) expression, both at the mRNA and protein level. It was also a strong inhibitor of VEGF expression, promoter activity, and in vitro angiogenesis. Finally, nimbolide suppressed the nuclear translocation of p65/p50 and DNA binding of NF-κB, which is an important transcription factor for controlling MMP-2/9 and VEGF gene expression.