Gene transfer of matrix metalloproteinase-9 induces tumor regression of breast cancer in vivo

Uncovering the anti-breast cancer activity potential of east Kalimantan propolis by In vitro and bioinformatics analysis

Numerous side effects of breast cancer drugs have prompted researchers to explore more into new therapeutic approaches derived from natural substances. In this context, our study focused on uncovering the potential of East Kalimantan propolis from Trigona apicalis for breast cancer treatment including the underlying mechanisms through bioinformatics approached. We conducted integrated in vitro and bioinformatics analysis of network pharmacology, molecular docking, molecular dynamics and MM-GBSA analysis. Initially, in vitro cytotoxic assay demonstrated the anti-breast cancer activity potential of ethanol extract of East Kalimantan propolis, particularly its ethyl acetate fraction, which exhibited similar activity to doxorubicin, as indicated by their IC50 value. This study revealed eight propolis compounds, consisting of flavonoids and phenolic acids, in East Kalimantan propolis. By integrating microarray datasets (GSE29431, GSE36295, and GSE42568) analysis with potential targets derived from propolis compounds, 39 shared target genes were identified. Subsequently, GO and KEGG pathway, protein-protein interaction (PPI) network, core hub genes and gene expression analysis revealed three major targets, namely, PTGS2, CXCL2, and MMP9. Among them, only MMP9 was highly expressed in breast cancer than normal. Moreover, molecular docking revealed the six of propolis compounds which exhibited pronounced binding affinity towards MMP-9, better than marimastat as control drug. Dynamic simulation confirmed the stability of chrysin and quercetin as best compounds. Additionally, MM-GBSA analysis revealed a relative binding energy for chrysin (-25.6403 kcal/mol) that was comparable to marimastat (-27.3827 kcal/mol). In conclusion, this study reveals how East Kalimantan Propolis affect breast cancer and emphasizes MMP9 as a key target for future therapeutics.

NECTIN4-targeted antibody-drug conjugate is a potential therapeutic option for extramammary Paget disease

Extramammary Paget disease (EMPD) is a rare skin cancer mainly found in areas rich in apocrine sweat glands. Since the effective treatments for advanced and/or metastasized EMPD are limited, there is an urgent need to develop novel therapeutic approaches. Nectin cell adhesion molecule 4 (NECTIN4) is highly expressed in cancers and considered to be a promising therapeutic target. NECTIN4 is also expressed in EMPD, but its role and the efficacy of NECTIN4-targeted therapy in EMPD remain unclear. This study investigated the potential of NECTIN4 as a novel therapeutic target for EMPD. NECTIN4 expression was immunohistochemically analysed in EMPD patients' primary (118 samples) and metastatic (21 samples) lesions. Using an EMPD cell line, KS-EMPD-1, the effects of NECTIN4 inhibition on cell proliferation and migration were investigated. NECTIN4 was expressed in primary and metastatic EMPD lesions, and the H-score of NECTIN4 staining was significantly higher in metastatic lesions than in primary ones. Knockdown of NECTIN4 significantly inhibited cell proliferation and affected cell migration. The cytotoxic effects of NECTIN4-targeted antibody-drug conjugate (ADC) were further evaluated, revealing a significant decrease in EMPD cell viability. In conclusion, NECTIN4 is a potential therapeutic target and NECTIN4-targeted ADC is promising as a therapeutic option for EMPD.

Effective voltammetric tool for simultaneous detection of MMP-1, MMP-2, and MMP-9; important non-small cell lung cancer biomarkers

Simultaneous detection of multiple biomarkers can allow to reduce the costs of medical diagnostics, and thus improve the accuracy and effectiveness of disease diagnosis and prognosis. Here, for the first time, we present a low-cost, simple, and rapid method for simultaneous detection of three matrix metalloproteinases (MMP-1, MMP-2, and MMP-9) that play important roles in the progression of lung cancer. The sensor matrix was constructed using a G2 polyamidoamine dendrimer (PAMAM) containing amino, carboxyl, and sulfhydryl groups. The recognition process was based on specific enzymatic cleavage of the Gly-Ile peptide bond by MMP-1, Gly-Leu bond by MMP-2, and Gly-Met bond by MMP-9, and monitoring was done by square wave voltammetry. The activity of metalloproteinases was detected based on the change of current signals of redox receptors (dipeptides labeled with electroactive compounds) covalently anchored onto the electrode surface. The conditions of the biosensor construction, including the concentration of receptors on the sensor surface and the time of interaction of the receptor with the analyte, were carefully optimized. Under optimal conditions, the linear response of the developed method ranged from 1.0⋅10^-8 to 1.0 mg⋅L^-1, and the limit of detection for MMP-1, MMP-2, and MMP-9 was 0.35, 0.62, and 1.10 fg⋅mL^-1, respectively. The constructed biosensor enabled us to efficiently profile the levels of active forms of MMP-1, MMP-2, and MMP-9 in tissue samples (plasma and lung and tumor extracts). Thus, the developed biosensor can aid in the early detection and diagnosis of lung cancer.

Matrix metalloproteinases as therapeutic targets in breast cancer

Matrix metalloproteinases (MMPs) are the most prominent proteinases involved in tumorigenesis. They were initially recognized to promote tumor progression by remodeling the extracellular matrix through their proteolytic activity. However, accumulating evidence has revealed that some MMPs have protective roles in cancer progression, and the same MMP can exert opposing roles depending on the cell type in which it is expressed or the stage of cancer. Moreover, studies have shown that MMPs are involved in cancer progression through their roles in other biological processes such as cell signaling and immune regulation, independent of their catalytic activity. Despite the prognostic significance of tumoral or stromal expression of MMPs in breast cancer, their roles and molecular mechanisms in breast cancer progression remain unclear. As the failures of early clinical trials with broad-spectrum MMP inhibitors were mainly due to a lack of drug specificity, substantial efforts have been made to develop highly selective MMP inhibitors. Some recently developed MMP inhibitory monoclonal antibodies demonstrated promising anti-tumor effects in preclinical models of breast cancer. Importantly, anti-tumor effects of these antibodies were associated with the modulation of tumor immune microenvironment, suggesting that the use of MMP inhibitors in combination with immunotherapy can improve the efficacy of immunotherapy in HER2-positive or triple-negative breast cancer. In this review, the current understanding of the roles of tumoral or stromal MMPs in breast cancer is summarized, and recent advances in the development of highly selective MMP inhibitors are discussed.

Immune-Related Gene Signatures to Predict the Effectiveness of Chemoimmunotherapy in Triple-Negative Breast Cancer Using Exploratory Subgroup Discovery

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited therapeutic options. Although immunotherapy has shown potential in TNBC patients, clinical studies have only demonstrated a modest response. Therefore, the exploration of immunotherapy in combination with chemotherapy is warranted. In this project we identified immune-related gene signatures for TNBC patients that may explain differences in patients' outcomes after anti-PD-L1+chemotherapy treatment. First, we ran the exploratory subgroup discovery algorithm on the TNBC dataset comprised of 422 patients across 24 studies. Secondly, we narrowed down the search to twelve homogenous subgroups based on tumor mutational burden (TMB, low or high), relapse status (disease-free or recurred), tumor cellularity (high, low and moderate), menopausal status (pre- or post) and tumor stage (I, II and III). For each subgroup we identified a union of the top 10% of genotypic patterns. Furthermore, we employed a multinomial regression model to predict significant genotypic patterns that would be linked to partial remission after anti-PD-L1+chemotherapy treatment. Finally, we uncovered distinct immune cell populations (T-cells, B-cells, Myeloid, NK-cells) for TNBC patients with various treatment outcomes. CD4-Tn-LEF1 and CD4-CXCL13 T-cells were linked to partial remission on anti-PD-L1+chemotherapy treatment. Our informatics pipeline may help to select better responders to chemoimmunotherapy, as well as pinpoint the underlying mechanisms of drug resistance in TNBC patients at single-cell resolution.

MMP9: A Tough Target for Targeted Therapy for Cancer

Having the capability to proteolyze diverse structural and signaling proteins, matrix metalloproteinase 9 (MMP9), one of the best-studied secretory endopeptidases, has been identified as a crucial mediator of processes closely associated with tumorigenesis, such as the extracellular matrix reorganization, epithelial to mesenchymal transition, cell migration, new blood vessel formation, and immune response. In this review, we present the current state of knowledge on MMP9 and its role in cancer growth in the context of cell adhesion/migration, cancer-related inflammation, and tumor microenvironment formation. We also summarize recent achievements in the development of selective MMP9 inhibitors and the limitations of using them as anticancer drugs.

Tumoral and stromal expression of MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2, and VEGF-A in cervical cancer patient survival: a competing risk analysis

BACKGROUND

Expression of matrix metalloproteases 2, 9 and 14 (MMP-2, MMP-9, MMP-14), tissue inhibitors of metalloprotease 1 and 2 (TIMP-1, TIMP-2) and vascular endothelial growth factor A (VEGF-A) is involved in tumor invasion and metastasis via extracellular matrix degradation and angiogenesis. This study aimed to assess whether the expression of MMP-2, MMP-9, MMP-14, TIMP-1, and TIMP-2 in tumors and in the adjacent stroma is associated with cervical cancer prognosis.

METHODS

This study analyzed a retrospective cohort of 64 patients. Protein expression was previously obtained by immunohistochemistry from biopsies containing both tumor and stroma. The expression and percentage of stained cells were categorized as high or low according to the cutoff points by using ROC curves. The follow-up data was collected from diagnosis to the last clinical visit. Clinical status categorized as alive without disease, alive with disease, death due to other causes, and death from the disease. The relative risk of death from the disease was evaluated according to the proteins expression using a cause-specific Cox regression model with a 95% confidence interval (95%CI). For the significant associations (p < 0.05), survival curves of patients with low and high expression were plotted for the competing risk survival curve analyses.

RESULTS

High expression levels of stromal MMP-2 (RR; 95%CI: 3.91; 1.17-13.02) and stromal TIMP-2 (RR, 95%CI: 8.67; 1.15-65.27) were associated with a greater relative risk of death from the disease and with lower survival (p = 0.03; p = 0.04) than lower expression levels. Low expression levels of stromal MMP-9 (RR, 95%CI: 0.19; 0.05-0.65) and tumoral MMP-9 (HR, 95%CI: 0.19; 0.04-0.90) were protective factors against death from the disease and were associated with poorer survival.

CONCLUSIONS

High expression levels of MMP-2 and TIMP-2 in the stroma were significantly associated with poor survival in cervical cancer patients. High expression of MMP-9 was associated with a favorable cervical cancer prognosis.

Molecular evaluation of chronic restrain stress in mice model of non metastatic fibrosarcoma

Chronic stress is regarded as a significant factor in the etiology of the many diseases. Numerous methods have been developed through which the effect of chronic stress is examined. The aim of this study is to demonstrate the new experimental model for analysis of immuno-suppression induced by chronic restraint stress, through challenge with conditionally tumorigenic cell line BHK-21/C13. 20 male NMRI mice were randomly divided into 2 groups-control and experimental. Each mouse was subcutaneously inoculated with BHK-21/C13 cells. Stress in the experimental group was induced for 20 days. After the experiment, tumor masses were removed, and analyzed using histology and immunohistochemistry techniques. We found a statistically significant difference (p = 0.034) in tumor expression and tumor volumes (p = 0.0061) between groups, as well as in immunopositivity on Ki67, cytochrome C and matrix metalloproteinase 9. Absence of immune infiltrate was noticed in experimental, and the presence of inflammatory infiltrate at tumor invasion front in control group.

Estradiol-Induced MMP-9 Expression via PELP1-Mediated Membrane-Initiated Signaling in ERα-Positive Breast Cancer Cells

Proline-, glutamic acid-, leucine-rich protein 1 (PELP1) is a novel estrogen receptor (ER) coregulator, demonstrated distinctive characters from other ERα coregulators, and has been suggested to be involved in metastasis of several cancers. In ERα-positive breast cancer, PELP1 overexpression enhanced ruffles and filopodium-like structure stimulated by estradiol (E₂) through extranuclear cell signaling transduction hereby increased cell motility. However, whether PELP1 is also involved in extracellular matrix remodeling of ERα-positive breast cancer cells is still unknown. In this study, we investigated the role of PELP1 in E₂-induced MMP-9 expression and the underlined mechanism. The results demonstrated the following: E₂-induced ERα-positive MCF-7 breast cancer cell MMP-9 mRNA and protein expression in a rapid response and concentration-dependent manner. Knocked down PELP1 significantly suppressed E₂-induced MMP-9 expression. E₂-bovine serum albumin (BSA), a large molecular membrane-impenetrable conjugate of E₂, can also upregulate MMP-9 protein expression in MCF-7, and the action of E₂-BSA can be abolished by PI3K inhibitor LY294002; treating MCF-7 simultaneously with PELP1-shRNA and LY294002 did not show synergetic inhibitory effect on E₂-BSA-induced MMP-9 expression. Our results indicated that estrogen-induced MMP-9 expression in ER-positive breast cancer cells may be through PELP1-mediated PI3K/Akt signaling pathway.

Mechanisms of Action of Novel Drugs Targeting Angiogenesis-Promoting Matrix Metalloproteinases

Angiogenesis is facilitated by the proteolytic activities of members of the matrix metalloproteinase (MMP) family. More specifically, MMP-9 and MT1-MMP directly regulate angiogenesis, while several studies indicate a role for MMP-2 as well. The correlation of MMP activity to tumor angiogenesis has instigated numerous drug development programs. However, broad-based and Zn²⁺-chelating MMP inhibitors have fared poorly in the clinic. Selective MMP inhibition by antibodies, biologicals, and small molecules has utilized unique modes of action, such as (a) binding to protease secondary binding sites (exosites), (b) allosterically blocking the protease active site, or (c) preventing proMMP activation. Clinical trials have been undertaken with several of these inhibitors, while others are in advanced pre-clinical stages. The mechanistically non-traditional MMP inhibitors offer treatment strategies for tumor angiogenesis that avoid the off-target toxicities and lack of specificity that plagued Zn²⁺-chelating inhibitors.

Relationship between serum MMP-9 level and prognosis after radical resection for Hilar cholangiocarcinoma patients

Purpose:

To analyze the preoperative serum matrix metalloproteinase-9 (MMP-9) levels and prognosis of patients with hilar cholangiocarcinoma (HC) undergoing radical resection.

Methods:

Preoperative serum MMP-9 levels in patients with HC undergoing radical resection were detected by enzyme-linked immunosorbent assay (ELISA). The ROC curve assay was used to analyze the preoperative serum MMP-9 level to determine the most valuable cut-off point. The relationship between MMP-9 and clinicopathological features of HC patients was analyzed. Kaplan-Meier method was used to analyze the prognostic factors, and COX regression model was used to analyze the independent risk factors affecting prognosis.

Results:

Preoperative serum MMP-9 levels were significantly elevated in the death patients compared with the survival patients. The most valuable cut-off point for preoperative serum MMP-9 for prognosis was 201.93 ng/mL. Preoperative serum MMP-9 was associated with Bismuth-Corlette classification) and lymph node metastasis. Kaplan-Meier analysis showed that MMP-9, Bismuth-Corlette classification, Lymph node metastasis, Portal vein invasion, Hepatic artery invasion, Liver invasion, Incised margin, and Preoperative biliary drainage were related to prognosis. Cox regression model confirmed that hepatic artery invasion, liver invasion, incised margin, and MMP-9 have the potential to independence predicate prognosis in HC patients.

Conclusion:

Preoperative serum MMP-9 has high predictive value for prognosis and is an independent influencing factor for the prognosis of patients with hilar cholangiocarcinoma.

Serum endostatin levels are associated with diffusion capacity and with tuberous sclerosis- associated lymphangioleiomyomatosis

Endostatin is a naturally occurring collagen fragment with anti-angiogenic properties. We investigated the association between serum endostatin levels and DLCO in a cohort of patients with lymphangioleiomyomatosis (LAM). Associations of endostatin levels to clinical features of LAM were explored using logistic regression models. Endostatin levels were associated with DLCO and were higher in subjects with TSC-associated LAM compared to sporadic LAM. These data suggest that endostatin could be a predictive biomarker of decline in DLCO and that germline mutational inactivation of the TSC1 or TSC2 gene is associated with higher endostatin levels. These findings could offer novel insights into the pathogenesis of LAM.

Combinatorial engineering of N-TIMP2 variants that selectively inhibit MMP9 and MMP14 function in the cell

Developing selective inhibitors for proteolytic enzymes that share high sequence homology and structural similarity is important for achieving high target affinity and functional specificity. Here, we used a combination of yeast surface display and dual-color selective library screening to obtain selective inhibitors for each of the matrix metalloproteinases (MMPs) MMP14 and MMP9 by modifying the non-specific N-terminal domain of the tissue inhibitor of metalloproteinase-2 (N-TIMP2). We generated inhibitor variants with 30- to 1175-fold improved specificity to each of the proteases, respectively, relative to wild type N-TIMP2. These biochemical results accurately predicted the selectivity and specificity obtained in cell-based assays. In U87MG cells, the activation of MMP2 by MMP14 was inhibited by MMP14-selective blockers but not MMP9-specific inhibitors. Target specificity was also demonstrated in MCF-7 cells stably expressing either MMP14 or MMP9, with only the MMP14-specific inhibitors preventing the mobility of MMP14-expressing cells. Similarly, the mobility of MMP9-expressing cells was inhibited by the MMP9-specific inhibitors, yet was not altered by the MMP14-specific inhibitors. The strategy developed in this study for improving the specificity of an otherwise broad-spectrum inhibitor will likely enhance our understanding of the basis for target specificity of inhibitors to proteolytic enzymes, in general, and to MMPs, in particular. We, moreover, envision that this study could serve as a platform for the development of next-generation, target-specific therapeutic agents. Finally, our methodology can be extended to other classes of proteolytic enzymes and other important target proteins.

Equal Pro-inflammatory Profiles of CCLs, CXCLs, and Matrix Metalloproteinases in the Extracellular Microenvironment In Vivo in Human Dense Breast Tissue and Breast Cancer

The inflammatory microenvironment affects breast cancer progression. Proteins that govern the inflammatory response are secreted into the extracellular space, but this compartment still needs to be characterized in human breast tissues in vivo. Dense breast tissue is a major risk factor for breast cancer by yet unknown mechanisms and no non-toxic prevention for these patients exists. Here, we used the minimal invasive technique of microdialysis for sampling of extracellular proteins in live tissues in situ in breast cancers of women before surgery and in healthy women having dense or non-dense breast tissue on mammography. Proteins were profiled using a proximity extension assay. Out of the 32 proteins assessed, 26 exhibited similar profiles in breast cancers and dense breast tissues; CCL-4, -7, -8, -11, -15, -16, -22, -23, and -25, CXCL-5, -8, -9, -16 as well as sIL-6R, IL-18, vascular endothelial growth factor, TGF-α, fibroblast growth factor 19, matrix metalloproteinase (MMP)-1, -2, -3, and urokinase-type plasminogen activator were all increased, whereas CCL-3, CX3CL1, hepatocyte growth factor, and MMP-9 were unaltered in the two tissues. CCL-19 and -24, CXCL-1 and -10, and IL-6 were increased in dense breast tissue only, whereas IL-18BP was increased in breast cancer only. Our results provide novel insights in the inflammatory microenvironment in human breast cancer in situ and define potential novel therapeutic targets. Additionally, we show previously unrecognized similarities of the pro-inflammatory microenvironment in dense breast tissue and breast cancer in vivo suggesting that anti-inflammatory breast cancer prevention trials for women with dense breast tissue may be feasible.

Expression of MMP-9 decreases metastatic potential of Chondrosarcoma: an immunohistochemical study

Background

Chondrosarcoma is the second most common primary malignant bone tumor. Because of their heterogeneity, with differences in invasive and metastatic behavior, it is important to identify biological markers that will allow for a more accurate estimation of prognosis in patients with these tumors.

Matrix metalloproteinases (MMP) play a crucial role in tumor progression, invasion and metastasis. The mechanism of tumor progression dependent of MMPs is complex and influences malignant transformation, angiogenesis and tumor growth at the primary and metastatic sites. The purpose of this study was to investigate immunohistochemicaly the influence of MMP-1, MMP-3, MMP-9 and MMP-13 expression on prognostic parameter in chondrosarcoma.

Methods

We investigated tissue samples of 28 patients with chondrosarcoma. Immunohistochemical staining to evaluate the expression of MMP-1, MMP-3, MMP-9 and MMP-13 was performed. Subsequently, the expression level was correlated with metastatic potential, histological grading and overall survival in patients with this neoplasm.

Results

In consideration of semi quantitative scoring 64% of chondrosarcoma were scored as positive for MMP-1, 46% for MMP-3, 61% for MMP-9. The specimens had shown no expression of MMP-13. High expression of MMP-9 was associated with better histological differentiation, decreased metastatic potential and favourable overall survival. No correlation was found for expression of MMP-1, MMP-3 or MMP-13.

Conclusions

MMP-1, MMP-3 and MMP-9 are expressed in chondrosarcoma. Our findings suggest that the expression of MMP-9 is associated with clinical outcome parameters in chondrosarcoma.

The interplay of matrix metalloproteinase-8, transforming growth factor-β1 and vascular endothelial growth factor-C cooperatively contributes to the aggressiveness of oral tongue squamous cell carcinoma

Background:

Matrix metalloproteinase-8 (MMP-8) has oncosuppressive properties in various cancers. We attempted to assess MMP-8 function in oral tongue squamous cell carcinoma (OTSCC).

Methods:

MMP-8 overexpressing OTSCC cells were used to study the effect of MMP-8 on proliferation, apoptosis, migration, invasion and gene and protein expression. Moreover, MMP-8 functions were assessed in the orthotopic mouse tongue cancer model and by immunohistochemistry in patient samples.

Results:

MMP-8 reduced the invasion and migration of OTSCC cells and decreased the expression of MMP-1, cathepsin-K and vascular endothelial growth factor-C (VEGF-C). VEGF-C was induced by transforming growth factor-β1 (TGF-β1) in control cells, but not in MMP-8 overexpressing cells. In human OTSCC samples, low MMP-8 in combination with high VEGF-C was an independent predictor of poor cancer-specific survival. TGF-β1 treatment also restored the migration of MMP-8 overexpressing cells to the level of control cells. In mouse tongue cancer, MMP-8 did not inhibit metastasis, possibly because it was eliminated in the peripheral carcinoma cells.

Conclusions:

The suppressive effects of MMP-8 in OTSCC may be mediated through interference of TGF-β1 and VEGF-C function and altered proteinase expression. Together, low MMP-8 and high VEGF-C expression have strong independent prognostic value in OTSCC.

Therapeutic Potential of Matrix Metalloproteinase Inhibition in Breast Cancer

Matrix metalloproteinases (MMPs) are a family of zinc endopeptidases that cleave nearly all components of the extracellular matrix as well as many other soluble and cell-associated proteins. MMPs have been implicated in normal physiological processes, including development, and in the acquisition and progression of the malignant phenotype. Disappointing results from a series of clinical trials testing small molecule, broad spectrum MMP inhibitors as cancer therapeutics led to a re-evaluation of how MMPs function in the tumor microenvironment, and ongoing research continues to reveal that these proteins play complex roles in cancer development and progression. It is now clear that effective targeting of MMPs for therapeutic benefit will require selective inhibition of specific MMPs. Here, we provide an overview of the MMP family and its biological regulators, the tissue inhibitors of metalloproteinases (TIMPs). We then summarize recent research from model systems that elucidate how specific MMPs drive the malignant phenotype of breast cancer cells, including acquisition of cancer stem cell features and induction of the epithelial-mesenchymal transition, and we also outline clinical studies that implicate specific MMPs in breast cancer outcomes. We conclude by discussing ongoing strategies for development of inhibitors with therapeutic potential that are capable of selectively targeting the MMPs most responsible for tumor promotion, with special consideration of the potential of biologics including antibodies and engineered proteins based on the TIMP scaffold. J. Cell. Biochem. 118: 3531-3548, 2017. © 2017 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.

Neutralization of matrix metalloproteinase-9 potentially enhances oncolytic efficacy of tanapox virus for melanoma therapy

Matrix metalloproteinases (MMPs), which are involved in degradation of extracellular matrix, are critical regulators in tumor progression, metastasis and angiogenesis. Although induction of MMPs is frequently observed during the viral infection, the effect of MMPs on viral replication varies between viruses. MMP-9, for instance, is upregulated and promotes the replication of some viruses, such as herpes simplex virus, but inhibits the replication of others. Here, we report that infection with tanapox virus (TPV) promotes the expression of MMP-9 in the melanoma cells. In addition, we show that MMP-9 exerts an anti-viral effect on TPV replication and plays a protective role in TPV-infected melanoma cells in vitro. Moreover, the neutralization of MMP-9 in melanoma cells remarkably enhances the TPV infection and leads to a significant reduction in cell survival. In summary, this study contributes to understanding of the role played by MMP-9 in TPV infectivity and provides more insights for using TPV as cancer virotherapy in future studies. Since TPV has shown substantial oncolytic efficacy in promoting melanoma tumor regression in animal models, identifying mechanisms that suppress MMP-9 expression upon TPV infection can potentially improve its use as a melanoma virotherapy.

Bortezomib and Arsenic Trioxide Activity on a Myelodysplastic Cell Line (P39): A Gene Expression Study

Objective:

We aimed to understand the molecular pathways affected by bortezomib and arsenic trioxide treatment on myelomonocytoid cell line P39.

Materials and Methods:

Oligonucleotide microarray platforms were used for gene expression and pathway analysis. Confirmation studies were performed using quantitative real time PCR.

Results:

Bortezomib treatment has shown upregulated DIABLO and NF-κBIB (a NF-κB inhibitor) and downregulated NF-κB1, NF-κB2, and BIRC1 gene expressions. Combination treatment of the two compounds showed gene expression deregulations in concordance by the results of single bortezomib treatment. Especially, P53 was a pathway more significantly modified and a gene network centralized around the beta estradiol gene. Beta estradiol, BRCA2, and FOXA1 genes were remarkable deregulations in our findings.

Conclusion:

Results support the suggestions about possible use of proteasome inhibitors in the treatment of high-risk myelodysplastic syndrome (MDS). NF-κB was observed as an important modulator in leukemic transformation of MDS.

BMP-6 inhibits the metastasis of MDA-MB-231 breast cancer cells by regulating MMP-1 expression

Bone morphogenetic protein-6 (BMP-6) is a multifunctional molecule with distinct abilities in embryogenesis and organogenesis. In the present study, our results showed that the rate of BMP-6-negative expression was 30.56% in breast cancer tissues, but was 9.58% in normal tissues by immunohistochemical staining. This implied that BMP-6 expression is absent in breast cancer tissues and may suppress breast cancer metastasis. In addition, stable overexpression of BMP-6 in MDA-MB‑231 cells was established to analyze the metastatic ability. The Boyden chamber assay showed that BMP-6 inhibited the migration and invasion of MDA-MB-231 cells. Moreover, real-time PCR analysis showed that BMP-6 markedly downregulated matrix metalloproteinase-1 (MMP-1) expression at both the mRNA and protein levels in the MDA-MB‑231 cells. Importantly, the results of luciferase and CHIP assays revealed that BMP-6 inhibited MMP-1 promoter activity through the AP-1 response element. In MDA-MB-231 cells treated with BMP-6, a significant decrease in the recruitment of AP-1 components, c-Jun/c-Fos, to the endogenous MMP-1 promoter was noted. We also demonstrated that BMP-6 inhibited the invasion of MDA-MB-231 cells, and this effect was significantly attenuated by overexpression of MMP-1. In contrast, MMP-1 knockdown by RNA interference or MMP-1 inhibitor exhibited an opposite effect. These observations suggest a novel role of BMP-6 in the inhibition of breast cancer metastasis by regulating secretion of MMPs in the tumor microenvironment.

Temporal cardiac remodeling post-myocardial infarction: dynamics and prognostic implications in personalized medicine

Despite dramatic improvements in short-term mortality rates following myocardial infarction (MI), long-term survival for MI patients who progress to heart failure remains poor. MI occurs when the left ventricle (LV) is deprived of oxygen for a sufficient period of time to induce irreversible necrosis of the myocardium. The LV response to MI involves significant tissue, cellular, and molecular level modifications, as well as substantial hemodynamic changes that feedback negatively to amplify the response. Inflammation to remove necrotic myocytes and fibroblast activation to form a scar are key wound healing responses that are highly variable across individuals. Few biomarkers of early remodeling stages are currently clinically adopted. The discovery of underlying pathophysiological mechanisms and associated novel biomarkers has the potential of improving prognostic capability and therapeutic monitoring. Combining these biomarkers with other prominent ones could constitute a powerful diagnostic and prognostic tool that directly reflects the pathophysiological remodeling of the LV. Understanding temporal remodeling at the tissue, cellular, and molecular level and its link to a well-defined set of biomarkers at early stages post-MI is a prerequisite for improving personalized care and devising more successful therapeutic interventions. Here we summarize the integral mechanisms that occur during early cardiac remodeling in the post-MI setting and highlight the most prominent biomarkers for assessing disease progression.

Matrix Metalloproteinase-9 Protects Islets from Amyloid-induced Toxicity

Deposition of human islet amyloid polypeptide (hIAPP, also known as amylin) as islet amyloid is a characteristic feature of the pancreas in type 2 diabetes, contributing to increased β-cell apoptosis and reduced β-cell mass. Matrix metalloproteinase-9 (MMP-9) is active in islets and cleaves hIAPP. We investigated whether hIAPP fragments arising from MMP-9 cleavage retain the potential to aggregate and cause toxicity, and whether overexpressing MMP-9 in amyloid-prone islets reduces amyloid burden and the resulting β-cell toxicity. Synthetic hIAPP was incubated with MMP-9 and the major hIAPP fragments observed by MS comprised residues 1-15, 1-25, 16-37, 16-25, and 26-37. The fragments 1-15, 1-25, and 26-37 did not form amyloid fibrils in vitro and they were not cytotoxic when incubated with β cells. Mixtures of these fragments with full-length hIAPP did not modulate the kinetics of fibril formation by full-length hIAPP. In contrast, the 16-37 fragment formed fibrils more rapidly than full-length hIAPP but was less cytotoxic. Co-incubation of MMP-9 and fragment 16-37 ablated amyloidogenicity, suggesting that MMP-9 cleaves hIAPP 16-37 into non-amyloidogenic fragments. Consistent with MMP-9 cleavage resulting in largely non-amyloidogenic degradation products, adenoviral overexpression of MMP-9 in amyloid-prone islets reduced amyloid deposition and β-cell apoptosis. These findings suggest that increasing islet MMP-9 activity might be a strategy to limit β-cell loss in type 2 diabetes.

Deregulated Levels of the NF-κB1, NF-κB2, and Rel Genes in Ukrainian Patients with Leukemia and Lymphoma in the Post-Chernobyl Period

Objective:

Nuclear factor kappa B (NF-κB) is an important transcription factor in cancer and NF-κB activation has been seen in angiogenesis, tumor progression, and metastasis. Relationships between specific NF-κB gene networks, leukemogenesis, and radiation exposure are still unknown. Our aim was to study the expression levels of the NF-κB1, NF-κB2, and Rel genes in hematological malignancies in the post-Chernobyl period.

Materials and Methods:

We analyzed gene expression levels of NF-κB1, NF-κB2, and Rel in 49 B-cell chronic lymphocytic leukemia, 8 B-cell non-Hodgkin’s lymphoma, 3 acute myeloid leukemia, 3 chronic myeloid leukemia, 2 hairy cell leukemia, 2 myelodysplastic syndrome, and 2 T-cell large granular lymphocytic leukemia patients using real-time polymerase chain reaction.

Results:

Expression levels of NF-κB1, NF-κB2, and Rel genes were found to be deregulated.

Conclusion:

These results could be accepted as specific gene traces to radiation-induced leukemia or as potential candidates for new diagnostic biomarker studies. Larger experiments and non-exposed control malignant cell populations are needed to clarify these suggestions.

Broad targeting of angiogenesis for cancer prevention and therapy

Deregulation of angiogenesis – the growth of new blood vessels from an existing vasculature – is a main driving force in many severe human diseases including cancer. As such, tumor angiogenesis is important for delivering oxygen and nutrients to growing tumors, and therefore considered an essential pathologic feature of cancer, while also playing a key role in enabling other aspects of tumor pathology such as metabolic deregulation and tumor dissemination/metastasis. Recently, inhibition of tumor angiogenesis has become a clinical anti-cancer strategy in line with chemotherapy, radiotherapy and surgery, which underscore the critical importance of the angiogenic switch during early tumor development. Unfortunately the clinically approved anti-angiogenic drugs in use today are only effective in a subset of the patients, and many who initially respond develop resistance over time. Also, some of the anti-angiogenic drugs are toxic and it would be of great importance to identify alternative compounds, which could overcome these drawbacks and limitations of the currently available therapy. Finding “the most important target” may, however, prove a very challenging approach as the tumor environment is highly diverse, consisting of many different cell types, all of which may contribute to tumor angiogenesis. Furthermore, the tumor cells themselves are genetically unstable, leading to a progressive increase in the number of different angiogenic factors produced as the cancer progresses to advanced stages. As an alternative approach to targeted therapy, options to broadly interfere with angiogenic signals by a mixture of non-toxic natural compound with pleiotropic actions were viewed by this team as an opportunity to develop a complementary anti-angiogenesis treatment option. As a part of the “Halifax Project” within the “Getting to know cancer” framework, we have here, based on a thorough review of the literature, identified 10 important aspects of tumor angiogenesis and the pathological tumor vasculature which would be well suited as targets for anti-angiogenic therapy: (1) endothelial cell migration/tip cell formation, (2) structural abnormalities of tumor vessels, (3) hypoxia, (4) lymphangiogenesis, (5) elevated interstitial fluid pressure, (6) poor perfusion, (7) disrupted circadian rhythms, (8) tumor promoting inflammation, (9) tumor promoting fibroblasts and (10) tumor cell metabolism/acidosis. Following this analysis, we scrutinized the available literature on broadly acting anti-angiogenic natural products, with a focus on finding qualitative information on phytochemicals which could inhibit these targets and came up with 10 prototypical phytochemical compounds: (1) oleanolic acid, (2) tripterine, (3) silibinin, (4) curcumin, (5) epigallocatechin-gallate, (6) kaempferol, (7) melatonin, (8) enterolactone, (9) withaferin A and (10) resveratrol. We suggest that these plant-derived compounds could be combined to constitute a broader acting and more effective inhibitory cocktail at doses that would not be likely to cause excessive toxicity. All the targets and phytochemical approaches were further cross-validated against their effects on other essential tumorigenic pathways (based on the “hallmarks” of cancer) in order to discover possible synergies or potentially harmful interactions, and were found to generally also have positive involvement in/effects on these other aspects of tumor biology. The aim is that this discussion could lead to the selection of combinations of such anti-angiogenic compounds which could be used in potent anti-tumor cocktails, for enhanced therapeutic efficacy, reduced toxicity and circumvention of single-agent anti-angiogenic resistance, as well as for possible use in primary or secondary cancer prevention strategies.

Identification of ApoA1, HPX and POTEE genes by omic analysis in breast cancer

Breast cancer is the most common cancer among women and accounts for 23% of all female types of cancers. It is well recognized that breast cancer represents a heterogeneous group of tumors, and the molecular events involved in the progression to cancer remain undetermined. Moreover, available prognostic and predictive markers are not sufficient for the accurate determination of the risk for many breast cancer patients. Thus, it is necessary to discover new molecular markers for accurate prediction of clinical outcome and individualized therapy. In the present study, we performed omics-based whole-genome trancriptomic and whole proteomic profiling with network and pathway analyses of breast tumors to identify gene expression patterns related to clinical outcome. A total of 20 samples from tumors and 14 normal appearing breast tissues were analyzed using both gene expression microarrays and LC-MS/MS. We identified 585 downregulated and 413 upregulated genes by gene expression microarrays. Among these genes, HPX, POTEE and ApoA1 were the most significant genes correlated with the proteomic profile. Our data revealed that these identified genes are closely related to breast cancer and may be involved in robust detection of disease progression.

Chitosan-based thermoreversible hydrogel as an in vitro tumor microenvironment for testing breast cancer therapies

Breast cancer is a major health problem for women worldwide. Although in vitro culture of established breast cancer cell lines is the most widely used model for preclinical assessment, it poorly represents the behavior of breast cancers in vivo. Acceleration of the development of effective therapeutic strategies requires a cost-efficient in vitro model that can more accurately resemble the in vivo tumor microenvironment. Here, we report the use of a thermoreversible poly(ethylene glycol)-g-chitosan hydrogel (PCgel) as an in vitro breast cancer model. We hypothesized that PCgel could provide a tumor microenvironment that promotes cultured cancer cells to a more malignant phenotype with drug and immune resistance. Traditional tissue culture plates and Matrigel were applied as controls in our studies. In vitro cellular proliferation and morphology, the secretion of angiogenesis-related growth factors and cytokines, and drug and immune resistance were assessed. Our results show that PCgel cultures promoted tumor aggregate formation, increased secretion of various angiogenesis- and metastasis-related growth factors and cytokines, and increased tumor cell resistance to chemotherapeutic drugs and immunotherapeutic T cells. This PCgel platform may offer a valuable strategy to bridge the gap between standard in vitro and costly animal studies for a wide variety of experimental designs.

Presence of intratumoral platelets is associated with tumor vessel structure and metastasis

Background

Platelets play a fundamental role in maintaining hemostasis and have been shown to participate in hematogenous dissemination of tumor cells. Abundant platelets were detected in the tumor microenvironment outside of the blood vessel, thus, platelet -tumor cell interaction outside of the bloodstream may play a role in regulating primary tumor growth and metastasis initiation. However, it is unclear that platelet depletion affects tumor vessel structure and dynamics.

Methods

Using thrombocytopenia induction in two different tumor-bearing mouse models, tumor tissues were performed by Westernblotting and immunohistochemical staining. Vascular permeability was evaluated by determination of intratumoral Evans blue and Miles vascular permeability assay. Furthermore, microdialysis was used to examining the intratumoral extracellular angiogenic growth factors (VEGF, TGF-β) by ELISA.

Results

Platelet depletion showed no change in tumor growth and reduced lung metastasis. Platelet depletion led to reduced tumor hypoxia and Met receptor activation and was associated with a decreased release of MMP-2, 9, PAI-1, VEGF, and TGF-β. Tumor vessels in platelet-depleted mice showed impaired vessel density and maturation.

Conclusions

Our findings demonstrate that platelets within the primary tumor microenvironment play a critical role in the induction of vascular permeability and initiation of tumor metastasis.

The influence of functional polymorphisms in matrix metalloproteinase 9 on survival of breast cancer patients in a Chinese population

Matrix metalloproteinase 9 (MMP9) plays a critical role in cancer aggression, and its overexpression is associated with a poor prognosis in breast cancer. Because common genetic variants can alter the expression or function of MMPs, we hypothesized that potentially functional single-nucleotide polymorphisms (SNPs) in the MMP9 gene may be associated with the survival of patients with invasive breast cancer. In this case-cohort follow-up study, a total of 245 breast cancer patients in southeast China were investigated, and five haplotype tagging SNPs (htSNPs) in the MMP9 gene were genotyped by using matrix-assisted laser desorption/ionization mass spectrometry and polymerase chain reaction-restriction fragment length polymorphism methods. Disease-free survival (DFS) and distance disease-free survival (DDFS) analyses were used to identify the SNPs associated with prognosis and determine their interdependence with the recognized prognostic factors. We found that the MMP9 rs3787268 GA+AA genotypes were significantly associated with poor DFS and DDFS of patients with breast cancer (log-rank p-values 0.045 and 0.028, respectively), especially in some subgroups of patients. Multivariate Cox regression and stepwise COX regression analyses suggested that rs3787268 may be a candidate independent biomarker to predict breast cancer survival in this population. Further, among estrogen receptor (ER)+/epidermal growth receptor 2 (HER-2)- patients, the rs3787268 GA+AA genotypes and rs17577 GG genotype showed a locus-dosage effect between combined the genotypes and decreased survival (adjusted HR 2.59, 95% confidence interval [CI] 1.29-5.19 and adjusted HR 3.25, 95% CI 1.39-7.58, respectively, for DFS and DDFS). Our results suggest that the polymorphisms in the MMP9 gene may be genetic modifiers for breast cancer prognosis in this Chinese population.

Inflammation induced by MMP-9 enhances tumor regression of experimental breast cancer

Matrix metalloproteinases (MMPs) have been suggested as therapeutic targets in cancer treatment, but broad-spectrum MMP inhibitors have failed in clinical trials. Recent data suggest that several MMPs including MMP-9 exert both pro- and antitumorigenic properties. This is also the case of the natural inhibitors of MMPs, tissue inhibitor of metalloproteinases (TIMPs). The inhibitor of MMP-9 is TIMP-1, and high levels of this enzyme have been associated with decreased survival in breast cancer. Inflammation is one hallmark of cancer progression, and MMPs/TIMPs may be involved in the local immune regulation. We investigated the role of MMP-9/TIMP-1 in regulating innate antitumor immunity in breast cancer. Breast cancers were established in nude mice and treated with intratumoral injections of adenoviruses carrying the human TIMP-1 or MMP-9 gene (AdMMP-9). In vivo microdialysis for sampling of cancer cell-derived (human) and stroma-derived (murine) proteins, immunostainings, as well as cell cultures were performed. We report a dose-dependent decrease of tumor growth and angiogenesis after AdMMP-9 treatment. In addition to increased generation of endostatin, AdMMP-9 promoted an antitumor immune response by inducing massive neutrophil infiltration. Neutrophil depletion prior to gene transfer abolished the therapeutic effects of AdMMP-9. Additionally, AdMMP-9 activated tumor-infiltrating macrophages into a tumor-inhibiting phenotype both in vivo and in vitro. AdMMP-9 also inhibited tumor growth in immune-competent mice bearing breast cancers. Adenoviruses carrying the human TIMP-1 gene had no effect on tumor growth or the immune response. Our novel data identify MMP-9 as a potent player in modulating the innate immune response into antitumor activities.

Fluctuating roles of matrix metalloproteinase-9 in oral squamous cell carcinoma

One hallmark of cancer is the degradation of the extracellular matrix (ECM), which is caused by proteinases. In oral cancers, matrix metalloproteinases (MMPs), especially MMP-9, are associated with this degradation. MMPs break down the ECM allowing cancer to spread; they also release various factors from their cryptic sites, including cytokines. These factors modulate cell behavior and enhance cancer progression by regulating angiogenesis, migration, proliferation, and invasion. The development of early metastases is typical for oral cancer, and increased MMP-9 expression is associated with a poor disease prognosis. However, many studies fail to relate MMP-9 expression with metastasis formation. Contrary to earlier models, recent studies show that MMP-9 plays a protective role in oral cancers. Therefore, the role of MMP-9 is complicated and may fluctuate throughout the different types and stages of oral cancers.

Matrix metalloproteinases 2, 7, and 9 in tumors and sera of patients with breast cancer

Enzyme immunoassay showed that the content of matrix metalloproteinases (MMP) 2 and 7 in tumors was higher than in the adjacent histologically intact tissue in 91 and 76% patients with breast cancer, respectively, while MMP-9 levels in the tumor and intact tissue were virtually the same. Serum concentrations of MMP-2 and MMP-7 did not correlate with their levels in the tumors, were within the normal range, and virtually did not decrease after removal of the primary tumor. Serum levels of MMP-9 in patients were significantly lower than in the control and increased after surgery in 85% patients. No clear-cut relationship between the studied parameters and clinical morphological prognostic factors of breast cancer was detected.

Endogenous angiogenesis inhibitors prevent adaptive capillary growth in left ventricular pressure overload hypertrophy

BACKGROUND

In left ventricular (LV) pressure-overload hypertrophy, lack of adaptive capillary growth contributes to progression to failure. Remodeling of the hypertrophied myocardium requires proteolysis of the extracellular matrix (ECM) carried out by matrix metalloproteinases (MMPs). MMPs, specifically MMP-9, are known to cleave ECM components to generate angiogenesis inhibitors (angiostatin, endostatin, tumstatin). We hypothesize that MMP-9 releases antiangiogenic factors during compensated and decompensated hypertrophy, which results in lack of adaptive capillary growth.

METHODS

Newborn rabbits underwent aortic banding. Myocardial tissue from age-matched and banded animals at compensated (4 weeks) and decompensated hypertrophy (7 weeks), as identified by serial echocardiography, was analyzed by immunoblotting for angiostatin, endostatin, and tumstatin. MMP-9 activity was determined by zymography. A cell-permeable, potent, selective MMP-9 inhibitor was administered intrapericardially to animals with hypertrophied hearts and tissue was analyzed.

RESULTS

MMP-9 is activated in hypertrophied myocardium versus in control hearts (22 ± 2 versus 16 ± 1; p = 0.04), which results in significantly increased levels of angiostatin (115 ± 10 versus 86 ± 7; p = 0.02), endostatin (33 ± 1 versus 28 ± 1; p = 0.006), and tumstatin (35 ± 6 versus 17 ± 4; p = 0.04). Zymography confirms inhibition of MMP-9 (hypertrophy + MMP-9 inhibitor, 14 ± 0.6 versus hypertrophy + vehicle, 17 ± 1; p = 0.01) and angiostatin, endostatin, and tumstatin are down-regulated, accompanied by up-regulation of capillary density (hypertrophy + MMP-9 inhibitor, 2.99 ± 0.07 versus hypertrophy + vehicle, 2.7 ± 0.05; p = 0.002).

CONCLUSIONS

Up-regulation of angiogenesis inhibitors prevents adaptive capillary growth in pressure-overload hypertrophied myocardium. Therapeutic interventions aimed at inhibition of angiogenesis inhibitors are useful in maintaining capillary density and thereby preventing heart failure.

Targeting Gene-Viro-Therapy with AFP driving Apoptin gene shows potent antitumor effect in hepatocarcinoma

Background

Gene therapy and viral therapy are used for cancer therapy for many years, but the results are less than satisfactory. Our aim was to construct a new recombinant adenovirus which is more efficient to kill hepatocarcinoma cells but more safe to normal cells.

Methods

By using the Cancer Targeting Gene-Viro-Therapy strategy, Apoptin, a promising cancer therapeutic gene was inserted into the double-regulated oncolytic adenovirus AD55 in which E1A gene was driven by alpha fetoprotein promoter along with a 55 kDa deletion in E1B gene to form AD55-Apoptin. The anti-tumor effects and safety were examined by western blotting, virus yield assay, real time polymerase chain reaction, 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, Hoechst33342 staining, Fluorescence-activated cell sorting, xenograft tumor model, Immunohistochemical assay, liver function analysis and Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling assay.

Results

The recombinant virus AD55-Apoptin has more significant antitumor effect for hepatocelluar carcinoma cell lines (in vitro) than that of AD55 and even ONYX-015 but no or little impair on normal cell lines. Furthermore, it also shows an obvious in vivo antitumor effect on the Huh-7 liver carcinoma xenograft in nude mice with bigger beginning tumor volume till about 425 mm3 but has no any damage on the function of liver. The induction of apoptosis is involved in AD55-Apoptin induced antitumor effects.

Conclusion

The AD55-Apoptin can be a potential anti-hepatoma agent with remarkable antitumor efficacy as well as higher safety in cancer targeting gene-viro-therapy system.

Human matrix metalloproteinases: an ubiquitarian class of enzymes involved in several pathological processes

Human matrix metalloproteinases (MMPs) belong to the M10 family of the MA clan of endopeptidases. They are ubiquitarian enzymes, structurally characterized by an active site where a Zn(2+) atom, coordinated by three histidines, plays the catalytic role, assisted by a glutamic acid as a general base. Various MMPs display different domain composition, which is very important for macromolecular substrates recognition. Substrate specificity is very different among MMPs, being often associated to their cellular compartmentalization and/or cellular type where they are expressed. An extensive review of the different MMPs structural and functional features is integrated with their pathological role in several types of diseases, spanning from cancer to cardiovascular diseases and to neurodegeneration. It emerges a very complex and crucial role played by these enzymes in many physiological and pathological processes.

Tamoxifen and flaxseed alter angiogenesis regulators in normal human breast tissue in vivo

The incidence of breast cancer is increasing in the Western world and there is an urgent need for studies of the mechanisms of sex steroids in order to develop novel preventive strategies. Diet modifications may be among the means for breast cancer prevention. Angiogenesis, key in tumor progression, is regulated by the balance between pro- and anti-angiogenic factors, which are controlled in the extracellular space. Sampling of these molecules at their bioactive compartment is therefore needed. The aims of this study were to explore if tamoxifen, one of the most used anti-estrogen treatments for breast cancer affected some of the most important endogenous angiogenesis regulators, vascular endothelial growth factor (VEGF), angiogenin, and endostatin in normal breast tissue in vivo and if a diet supplementation with flaxseed had similar effects as tamoxifen in the breast. Microdialysis was used for in situ sampling of extracellular proteins in normal breast tissue of women before and after six weeks of tamoxifen treatment or before and after addition of 25 g/day of ground flaxseed to the diet or in control women. We show significant correlations between estradiol and levels of VEGF, angiogenin, and endostatin in vivo, which was verified in ex vivo breast tissue culture. Moreover, tamoxifen decreased the levels of VEGF and angiogenin in the breast whereas endostatin increased significantly. Flaxseed did not alter VEGF or angiogenin levels but similar to tamoxifen the levels of endostatin increased significantly. We conclude that one of the mechanisms of tamoxifen in normal breast tissue include tipping of the angiogenic balance into an anti-angiogenic state and that flaxseed has limited effects on the pro-angiogenic factors whereas the anti-angiogenic endostatin may be modified by diet. Further studies of diet modifications for breast cancer prevention are warranted.

Matrix metalloproteinases: protective roles in cancer

The original notion that matrix metalloproteinases (MMPs) act as tumour and metastasis-promoting enzymes by clearing a path for tumour cells to invade and metastasize has been challenged in the last decade. It has become clear that MMPs are involved in numerous steps of tumour progression and metastasis, and hence are now considered to be multifaceted proteases. Moreover, more recent experimental evidence indicates that some members of the MMP family behave as tumour-suppressor enzymes and should therefore be regarded as anti-targets in cancer therapy. The complexity of the pro- and anti-tumorigenic and -metastatic functions might partly explain why broad-spectrum MMP inhibitors failed in phase III clinical trials. This review will provide a focussed overview of the published data on the tumour-suppressive behaviour of MMPs.

In vitro anti-angiogenic properties of LGD1069, a selective retinoid X-receptor agonist through down-regulating Runx2 expression on Human endothelial cells

Background

LGD1069 (Targretin^®) is a selective retinoid X receptor (RXR) ligand, which is used in patients for cutaneous T-cell lymphoma. Our published study reported that LGD1069 inhibited tumor-induced angiogenesis in non-small cell lung cancer. In present study, we found that LGD1069 suppressed the proliferation, adhesion, invasion and migration of endothelial cells directly, and affected the expression of vegf and some matrix genes.

Methods

Human umbilical vein endothelial cells (HUVECs) were used for in vitro study. MTT assay and Sulforhodamine B assay were used for cell viability assay; the tube formation assay was used to investigate the effect of LGD1069 on angiogenesis in vitro. In vitro adhesion, migration and invasion of HUVEC cells were analyzed by Matrigel adhesion, migration and invasion assay. Gene expressions were measured by RT-PCR and Western blot analysis.

Results

Our data showed here that LGD1069 inhibited the activation of TGF-β/Smad pathway significantly. Furthermore, it was demonstrated that expression of Runx2 was suppressed pronouncedly during incubation with LGD1069. Runx2 is a DNA-binding transcription factor which plays a master role in tumor-induced angiogenesis and cancer cells metastasis by interaction with the TGF-β/Smad pathway of transcriptional modulators.

Conclusions

Our results suggested that LGD1069 may impair angiogenic and metastatic potential induced by tumor cells through suppressing expression of Runx2 directly on human endothelial cells, which may point out new pathway through which LGD1069 display anti-angiogenic properties, and provide new molecular evidence to support LGD1069 as a potent anti-metastatic agent in cancer therapy.

Catalytic activity of Matrix metalloproteinase-19 is essential for tumor suppressor and anti-angiogenic activities in nasopharyngeal carcinoma

The association of Matrix metalloproteinase-19 (MMP19) in the development of nasopharyngeal carcinoma (NPC) was identified from differential gene profiling, which showed MMP19 was one of the candidate genes down-regulated in the NPC cell lines. In this study, quantitative RT-PCR and Western blot analysis showed MMP19 was down-regulated in all seven NPC cell lines. By tissue microarray immunohistochemical staining, MMP19 appears down-regulated in 69.7% of primary NPC specimens. Allelic deletion and promoter hypermethylation contribute to MMP19 down-regulation. We also clearly demonstrate that the catalytic activity of MMP19 plays an important role in antitumor and antiangiogenesis activities in comparative studies of the wild-type and the catalytically inactive mutant MMP19. In the in vivo tumorigenicity assay, only the wild-type (WT), but not mutant, MMP19 transfectants suppress tumor formation in nude mice. In the in vitro colony formation assay, WT MMP19 dramatically reduces colony-forming ability of NPC cell lines, when compared to the inactive mutant. In the tube formation assay of human umbilical vein endothelial cells and human microvascular endothelial cells (HMEC-1), secreted WT MMP19, but not mutant MMP19, induces reduction of tube-forming ability in endothelial cells with decreased vascular endothelial growth factor (VEGF) in conditioned media detected by enzyme-linked immunosorbent assay (ELISA). The anti-angiogenic activity of WT MMP19 is correlated with suppression of tumor formation. These results now clearly show that catalytic activity of MMP19 is essential for its tumor suppressive and anti-angiogenic functions in NPC.

BMP-6 inhibits MMP-9 expression by regulating heme oxygenase-1 in MCF-7 breast cancer cells

PURPOSE

BMP-6, which belongs to the TGF-β superfamily, is a multifunctional molecule with distinct abilities in embryogenesis and organogenesis. Our recent research has implied that BMP-6 may suppress breast cancer metastasis. In the present study, we extended to elucidate the molecular mechanism by which BMP-6 exerts its anti-tumorigenic effect.

METHODS

The Boyden chamber assay was used to examine the ability of BMP-6 and HO-1 in MCF-7 malignant progress. RT-PCR, western blot, luciferase assay, and quantitative CHIP were used to determine the potential mechanism and signaling pathways by which BMP-6 and HO-1 function as anti-metastatic factors in MCF-7 cells.

RESULTS

The Boyden chamber assay showed that BMP-6 inhibited the migration and invasion of MCF-7 cells, which effect was significantly deprived by knockdown of HO-1. We further demonstrated that BMP-6 treatment resulted in an activation of HO-1 transcription through the recruitment of Smad1/5 to the Smad-responsive element on its promoter. In addition, BMP-6-induced up-regulation of HO-1 exhibited an inhibitory effect on MMP-9 secretion in a paracrine action in MCF-7 cells. Overexpression of BMP-6 and HO-1 synergistically suppressed MMP-9 transcription, which effect was specifically mediated via the MAPK/p38/AP-1 signaling. However, blockade of HO-1 using ZnPPIX totally abolished BMP-6-regulated MMP-9 activation in MCF-7 cells.

CONCLUSIONS

These observations suggest a novel role of BMP-6/HO-1 cascade to relieve breast cancer metastasis by regulating the secretion of growth factors in tumor microenvironment.

Role of anti-angiogenic factor endostatin in the pathogenesis of experimental ulcerative colitis

AIMS

Vascular endothelial growth factor (VEGF) and pathologic angiogenesis have been demonstrated to play a pathogenic role in the development and progression of inflammatory bowel disease. Thus, we hypothesized that the potent anti-angiogenic factor endostatin might play a beneficial role in experimental ulcerative colitis (UC).

MAIN METHODS

We used three animal models of UC: (1) induced by 6% iodoacetamide (IA) in rats, or (2) by 3% dextran sulfate sodium (DSS) in matrix metalloproteinase-9 (MMP-9) knockout (KO) and wild-type mice, and (3) interleukin-10 (IL-10) KO mice. Groups of MMP-9 KO mice with DSS-induced UC were treated with endostatin or water for 5days.

KEY FINDINGS

We found concomitant upregulation of VEGF, PDGF, MMP-9 and endostatin in both rat and mouse models of UC. A positive correlation between the levels of endostatin or VEGF and the sizes of colonic lesions was seen in IA-induced UC. The levels and activities of MMP-9 were also significantly increased during UC induced by IA and IL-10 KO. Deletion of MMP-9 decreased the levels of endostatin in both water- and DSS-treated MMP-9 KO mice. Treatment with endostatin significantly improved DSS-induced UC in MMP-9 KO mice.

SIGNIFICANCE

1) Concomitantly increased endostatin is a defensive response to the increased VEGF in UC, 2) MMP-9 is a key enzyme to generate endostatin which may modulate the balance between VEGF and endostatin during experimental UC, and 3) endostatin treatment plays a beneficial role in UC. Thus, anti-angiogenesis seems to be a new therapeutic option for UC.

The extracellular matrix in digestive cancer

The extracellular components of the cancer microenvironment play a critical role in tumor initiation, progression and invasion. In this review we examine the normal formation and function of the basement membrane and extracellular matrix. We characterize the interactions between the matrix and the epithelium and explore the causes and consequences of the extracellular remodeling that accompanies carcinogenesis. Finally, we address the therapeutic possibilities of incorporating matrix as well as epithelial strategies in the management of digestive cancer.

Ectopic matrix metalloproteinase-9 expression in human brain tumor cells enhances oncolytic HSV vector infection

Oncolytic herpes simplex virus (oHSV) vectors have shown promise in the treatment of patients with recurrent brain tumors although few complete responses have accrued. Impediments to effective therapy include limited vector distribution on delivery, a consequence of injected virion particle trapping in the tumor extracellular matrix (ECM). To enhance virus delivery and spread, we investigated the use of the matrix metalloproteinase-9 (MMP-9) as a means to degrade collagen type IV, a major component of the ECM and basement membranes of gliomas that is absent in normal brain tissue. SK-N-AS neuroblastoma cells were transduced for constitutive, elevated expression of MMP-9, which did not enhance tumor cell migration in vitro or tumor progression in a murine xenograft brain tumor model. MMP-9 expression improved the distribution and infection of oHSV vectors in spheroid model in vitro. Furthermore, MMP9 induced a vector infection over larger areas of brain tumors in vivo. These results suggest that vector delivery and distribution in vivo can be improved by compromising the ECM, potentially enhancing oncolytic efficacy.

Navigating ECM barriers at the invasive front: the cancer cell-stroma interface

A seminal event in cancer progression is the ability of the neoplastic cell to mobilize the necessary machinery to breach surrounding extracellular matrix barriers while orchestrating a host stromal response that ultimately supports tissue-invasive and metastatic processes. With over 500 proteolytic enzymes identified in the human genome, interconnecting webs of protease-dependent and protease-independent processes have been postulated to drive the cancer cell invasion program via schemes of daunting complexity. Increasingly, however, a body of evidence has begun to emerge that supports a unifying model wherein a small group of membrane-tethered enzymes, termed the membrane-type matrix metalloproteinases (MT-MMPs), plays a dominant role in regulating cancer cell, as well as stromal cell, traffic through the extracellular matrix barriers assembled by host tissues in vivo. Understanding the mechanisms that underlie the regulation and function of these metalloenzymes as host cell populations traverse the dynamic extracellular matrix assembled during neoplastic states should provide new and testable theories regarding cancer invasion and metastasis.

Increased endostatin generation and decreased angiogenesis via MMP-9 by tamoxifen in hormone dependent ovarian cancer

There are several similarities between breast and ovarian cancer but anti-estrogen treatment is rarely used in ovarian cancer. We have previously shown that the most widely used anti-estrogen tamoxifen increased MMP-9 activity and endostatin generation in breast cancer. Here, we show that tamoxifen exposure of highly hormone responsive ovarian cancer cells decreased proliferation, and increased MMP-9 activity leading to increased levels of endostatin both in cell culture in vitro and in solid tumors of nude mice. Tamoxifen exposed tumors also exhibited significantly decreased tumor growth and vascularisation. Moreover, in ascites from ovarian cancer patients, MMP-9 was undetectable in majority of cases but a significant correlation of MMP-2 and endostatin was found. The effects on MMPs and endostatin generation are previously unknown mechanisms of estradiol and tamoxifen in ovarian cancer, which may have therapeutic implications in future anti-cancer options of hormone dependent ovarian cancer.

Potent antitumor effect of interleukin-24 gene in the survivin promoter and retinoblastoma double-regulated oncolytic adenovirus

Interleukin (IL)-24 is an excellent therapeutic gene for cancer therapy. In this work, IL-24 was inserted into Ad.sp-E1A(Delta24), an oncolytic adenovirus with a 24-bp deletion in the E1A gene, which was driven by the survivin promoter to form Ad.sp-E1A(Delta24)-IL-24. Ad.sp-E1A(Delta24)-IL-24 has an excellent antitumor effect in vitro for human nasopharyngeal, liver, lung, and cervical carcinoma cell lines but does no or little damage to normal cell lines L-02 and WI38. Furthermore, it achieved nearly complete inhibition (although not elimination) of NCI-H460 lung carcinoma growth in nude mice. The antitumor efficacy of Ad.sp-E1A(Delta24)-IL-24 on NCI-H460 cells was clearly mediated by apoptosis, because it induced caspase-3 and poly(ADP-ribose) polymerase cleavage. This is the first report of Ad.sp-E1A(Delta24)-IL-24 with such an excellent, broad, and specific antitumor effect in vitro and nearly complete inhibition of lung tumor growth in vivo.

Matrix metalloproteinase proteomics: substrates, targets, and therapy

Proteomics encompasses powerful techniques termed 'degradomics' for unbiased high-throughput protease substrate discovery screens that have been applied to an important family of extracellular proteases, the matrix metalloproteinases (MMPs). Together with the data generated from genetic deletion and transgenic mouse models and genomic profiling, these screens can uncover the diverse range of MMP functions, reveal which MMPs and MMP-mediated pathways exacerbate pathology, and which are involved in protection and the resolution of disease. This information can be used to identify and validate candidate drug targets and antitargets, and is critical for the development of new inhibitors of MMP function. Such inhibitors may target either the MMP directly in a specific manner or pathways upstream and downstream of MMP activity that are mediating deleterious effects in disease. Since MMPs do not operate alone but are part of the 'protease web', it is necessary to use system-wide approaches to understand MMP proteolysis in vivo, to discover new biological roles and their potential for therapeutic modification.