Analysis of the MMP-dependent and independent functions of tissue inhibitor of metalloproteinase-2 on the invasiveness of breast cancer cells

Glutamine metabolism promotes human trophoblast cell invasion via COL1A1 mediated by PI3K-AKT pathway

Abnormal trophoblast invasion function is an important cause of recurrent spontaneous abortion (RSA). Recent research has revealed a connection between glutamine metabolism and RSA. However, the interplay between these three factors and their related mechanisms remains unclear. To address this issue, we collected villus tissues from 10 healthy women with induced abortion and from 10 women with RSA to detect glutamine metabolism. Then, the trophoblast cell line HTR-8/SVneo was used in vitro to explore the effect of glutamine metabolism on trophoblast cells invasion, which was tested by transwell assay. We found that the concentration of glutamine in the villi of the normal pregnancy group was significantly higher than that in the RSA group. Correspondingly, the expression levels of key enzymes involved in glutamine synthesis and catabolism, including glutamine synthetase and glutaminase, were significantly higher in the villi of the normal pregnancy group. Regarding trophoblast cells, glutamine markedly enhanced the proliferative and invasive abilities of HTR-8/SVneo cells. Additionally, collagen type I alpha 1 (COL1A1) was confirmed to be a downstream target of glutamine, and glutamine also activated the PI3K-AKT pathway in HTR-8/SVneo cells. These findings indicate that glutamine metabolism facilitates the invasion of trophoblasts by up-regulating COL1A1 expression through the activation of the PI3K-AKT pathway, but the specific mechanism of COL1A1 requires further study.

Phenotypically sorted highly and weakly migratory triple negative breast cancer cells exhibit migratory and metastatic commensalism

BACKGROUND

Intratumor heterogeneity is a well-established hallmark of cancer that impedes cancer research, diagnosis, and treatment. Previously, we phenotypically sorted human breast cancer cells based on migratory potential. When injected into mice, highly migratory cells were weakly metastatic and weakly migratory cells were highly metastatic. The purpose of this study was to determine whether these weakly and highly migratory cells interact with each other in vitro or in vivo.

METHODS

To assess the relationship between heterogeneity in cancer cell migration and metastatic fitness, MDA-MB-231 and SUM159PT triple negative breast cancer cells were phenotypically sorted into highly migratory and weakly migratory subpopulations and assayed separately and in a 1:1 mixture in vitro and in vivo for metastatic behaviors. Unpaired, two-tailed Student's t-tests, Mann-Whitney tests, ordinary, one-way ANOVAs, and Kruskal-Wallis H tests were performed as appropriate with p < 0.05 as the cutoff for statistical significance.

RESULTS

When highly and weakly migratory cells are co-seeded in mixed spheroids, the weakly migratory cells migrated farther than weakly migratory only spheroids. In mixed spheroids, leader-follower behavior occurred with highly migratory cells leading the weakly migratory cells in migration strands. When cell suspensions of highly migratory, weakly migratory, or a 1:1 mixture of both subpopulations were injected orthotopically into mice, both the mixed cell suspensions and weakly migratory cells showed significant distal metastasis, but the highly migratory cells did not metastasize significantly to any location. Notably, significantly more distal metastasis was observed in mice injected with the 1:1 mixture compared to either subpopulation alone.

CONCLUSIONS

This study suggests that weakly migratory cells interact with highly migratory cells in a commensal fashion resulting in increased migration and metastasis. Together, these findings indicate that cancer cell subpopulation migration ability does not correlate with metastatic potential and that cooperation between highly migratory and weakly migratory subpopulations can enhance overall metastatic fitness.

Tumor necrosis factor α, protein gene product 9.5, matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 presence in congenital intra-abdominal adhesions in children under one year of age

INTRODUCTION

The regulatory role of cytokines and extracellular matrix remodeling factors in congenital intra-abdominal adhesions has not yet been defined. The aim of this study was to assess the presence and relative distribution of tumor necrosis factor α (TNF-α), protein gene product 9.5 (PGP 9.5), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in adhesions.

MATERIAL AND METHODS

TNF-α, PGP 9.5, MMP-2 and TIMP-2 were detected using immunohistochemical methods and their relative distribution was evaluated by means of the semiquantitative counting method. The results were analyzed using non-parametric statistical methods.

RESULTS

A moderate number of TNF-α positive macrophages and fibroblasts was found. A positive correlation was observed between the immunoreactive structures for TNF-α and PGP 9.5. A positive reaction for PGP 9.5 was observed in nerve fibers and shape modified fibroblasts. In control group tissues, positive structures were seen in significantly higher counts for PGP 9.5. Few to moderate numbers of MMP-2 positive macrophages, epithelioid cells, fibroblasts and endotheliocytes were detected. There was no significant difference between the groups. A positive reaction for TIMP-2 was seen in fibroblasts, macrophages and endotheliocytes. In control group tissues, positive structures were found in significantly higher counts for TIMP-2.

CONCLUSIONS

The positive correlation between the immunoreactive structures for TNF-α and PGP 9.5 suggests that nerve in-growth into intraabdominal adhesions might be induced by TNF-α and PGP 9.5 could have a role in maintaining inflammation. The down-regulation of PGP 9.5 suggests that pathogenesis of congenital intraabdominal adhesions may be related to hypoxia induced damage. The imbalance between MMP-2 and TIMP-2 may prove tissue fibrosis as a response to congenital peritoneal adhesions.

TIMP-2 suppresses tumor growth and metastasis in murine model of triple-negative breast cancer

Metastasis is the primary cause of treatment failures and mortality in most cancers. Triple-negative breast cancer (TNBC) is refractory to treatment and rapidly progresses to disseminated disease. We utilized an orthotopic mouse model that molecularly and phenotypically resembles human TNBC to study the effects of exogenous, daily tissue inhibitor of metalloproteinase-2 (TIMP-2) treatment on tumor growth and metastasis. Our results demonstrated that TIMP-2 treatment maximally suppressed primary tumor growth by ~36-50% and pulmonary metastasis by >92%. Immunostaining assays confirmed disruption of the epithelial to mesenchymal transition (EMT) and promotion of vascular integrity in primary tumor tissues. Immunostaining and RNA sequencing analysis of lung tissue lysates from tumor-bearing mice identified significant changes associated with metastatic colony formation. Specifically, TIMP-2 treatment disrupts periostin localization and critical cell-signaling pathways, including canonical Wnt signaling involved in EMT, as well as PI3K signaling, which modulates proliferative and metastatic behavior through p27 phosphorylation/localization. In conclusion, our study provides evidence in support of a role for TIMP-2 in suppression of triple-negative breast cancer growth and metastasis through modulation of the epithelial to mesenchymal transition, vascular normalization, and signaling pathways associated with metastatic outgrowth. Our findings suggest that TIMP-2, a constituent of the extracellular matrix in normal tissues, may have both direct and systemic antitumor and metastasis suppressor effects, suggesting potential utility in the clinical management of breast cancer progression.

Oral administration of N-acetyl cysteine prevents osteoarthritis development and progression in a rat model

The number of osteoarthritis patients is increasing with the rise in the number of elderly people in developed countries. Osteoarthritis, which causes joint pain and deformity leading to loss of activities of daily living, is often treated surgically. Here we show that mechanical stress promotes accumulation of reactive oxygen species (ROS) in chondrocytes in vivo, resulting in chondrocyte apoptosis and leading to osteoarthritis development in a rat model. We demonstrate that mechanical stress induces ROS accumulation and inflammatory cytokine expression in cultured chondrocytes in vitro and that both are inhibited by treatment with the anti-oxidant N-acetyl cysteine (NAC). In vivo, osteoarthritis development in a rat osteoarthritis model was also significantly inhibited by oral administration of NAC. MMP13 expression and down-regulation of type II collagen in chondrocytes, both of which indicate osteoarthritis, as well as chondrocyte apoptosis in osteoarthritis rats were inhibited by NAC. Interestingly, osteoarthritis development in sham-operated control sides, likely due to disruption of normal weight-bearing activity on the control side, was also significantly inhibited by NAC. We conclude that osteoarthritis development in rats is significantly antagonized by oral NAC administration. Currently, no oral medication is available to prevent osteoarthritis development. Our work suggests that NAC may represent such a reagent and serve as osteoarthritis treatment.

Diagnostic Power of Cytokine M-CSF, Metalloproteinase 2 (MMP-2) and Tissue Inhibitor-2 (TIMP-2) in Cervical Cancer Patients Based on ROC Analysis

Macrophage colony-stimulating factor (M-CSF), matrix metalloproteinase-2 (MMP-2) and its specific tissue inhibitor (TIMP-2) may play an important role in the pathogenesis of cancer disease. We investigated the plasma levels and diagnostic power (ROC curve analysis) of M-CSF, MMP-2, TIMP-2 and tumor markers CA 125 and SCC-Ag in cervical cancer (CC) patients as compared to control group. The study included 89 patients with cervical cancer. The control group consisted of 50 healthy, untreated women. The plasma levels of M-CSF, MMP-2 and TIMP-2 were determined using ELISA, CA 125 and SCC-Ag – by CMIA method. The median levels of M-CSF, TIMP-2, SCC-Ag and CA 125 in the entire group of CC were significantly different than compared to the healthy women group. MMP-2 showed the highest value of sensitivity from all examined parameters (in stage I of CC – 93.10%, II – 82.76%, III and IV – 96.88%, total group – 92.05%). The highest specificity was obtained by M-CSF (86%). The area under the ROC curve (AUC) of M-CSF (0.8051) was the largest of all the tested parameters (even higher than commonly used tumor markers) in the group of cervical cancer. The combination of M-CSF, MMP-2 or TIMP-2 with SCC antigen resulted in an increase AUCs in all cases (0.8760;0.7880;0.8081;respectively). The findings of this study suggest the usefulness of all examined parameters in the diagnostics of CC patients. Out of the tested substances, M-CSF also appears to be the best candidate for cancer diagnostics in all stages of the disease, based on ROC analysis.

The matrix protein Fibulin-3 promotes KISS1R induced triple negative breast cancer cell invasion

Breast cancer is a leading cause of cancer mortality. In particular, triple negative breast cancer (TNBC) comprise a heterogeneous group of basal-like tumors lacking estrogen receptor (ERα), progesterone receptor (PR) and HER2 (ErbB2). TNBC represents 15-20% of all breast cancers and occurs frequently in women under 50 years of age. Unfortunately, these patients lack targeted therapy, are typically high grade and metastatic at time of diagnosis. The mechanisms regulating metastasis remain poorly understood. We have previously shown that the kisspeptin receptor, KISS1R stimulates invasiveness of TNBC cells. In this report, we demonstrate that KISS1R signals via the secreted extracellular matrix protein, fibulin-3, to regulate TNBC invasion. We found that the fibulin-3 gene is amplified in TNBC primary tumors and that plasma fibulin-3 levels are elevated in TNBC patients compared to healthy subjects. In this study, we show that KISS1R activation increases fibulin-3 expression and secretion. We show that fibulin-3 regulates TNBC metastasis in a mouse experimental metastasis xenograft model and signals downstream of KISS1R to stimulate TNBC invasion, by activating matrix metalloproteinase 9 (MMP-9) and the MAPK pathway. These results identify fibulin-3 as a new downstream mediator of KISS1R signaling and as a potential biomarker for TNBC progression and metastasis, thus revealing KISS1R and fibulin-3 as novel drug targets in TNBC.

The Many Facets of Metzincins and Their Endogenous Inhibitors: Perspectives on Ovarian Cancer Progression

Approximately sixty per cent of ovarian cancer patients die within the first five years of diagnosis due to recurrence associated with chemoresistance. The metzincin family of metalloproteinases is enzymes involved in matrix remodeling in response to normal physiological changes and diseased states. Recently, there has been a mounting awareness of these proteinases and their endogenous inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), as superb modulators of cellular communication and signaling regulating key biological processes in cancer progression. This review investigates the role of metzincins and their inhibitors in ovarian cancer. We propose that understanding the metzincins and TIMP biology in ovarian cancer may provide valuable insights in combating ovarian cancer progression and chemoresistance-mediated recurrence in patients.

Stable expression of α1-antitrypsin Portland in MDA-MB-231 cells increased MT1-MMP and MMP-9 levels, but reduced tumour progression

The membrane bound matrix metalloproteinase MT1-MMP plays roles in modulating cell movement, independent of its abilities to remodel the extracellular matrix. Unlike many MMPs, MT1-MMP is activated in the Golgi prior to secretion by a pro-protein convertase, primarily furin. Regulation of the activation of pro-MT1-MMP has been methodically investigated, as altering the level of the active protein has broad implications in both activating other pro-MMPs, including pro-MMP-2, and many subsequent remodelling events. Our previous work in MCF-7 cells has demonstrated that modest, and not extremely high, levels of active MT1-MMP manifests into altered cell morphology and movement. At this low but optimal amount of MT1-MMP protein, changes to MT1-MMP levels are always mirrored by MMP-9 and pERK levels, and always opposite to MMP-2 levels. In this study, stable expression of the furin inhibitor α1-antitrypsin Portland (α1-PDX) in MDA-MB-231 cells increased overall MT1-MMP levels, but cells maintained a 21% proportion of pro-MT1-MMP. The increase in MT1-MMP was mirrored by increases in MMP-9 and pERK, but a decrease in MMP-2. These changes were associated with increased NF-κB transcription. In vitro analysis showed that α1-PDX decreased cell protrusions and migration, and this manifested as decreased tumourigenesis when examined in vivo using a chick CAM assay.

Plasma levels and diagnostic utility of VEGF, MMP-2 and TIMP-2 in the diagnostics of breast cancer patients

OBJECTIVE

We investigated plasma levels and diagnostic utility of vascular endothelial growth factor VEGF, matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinase-2 (TIMP-2) in comparison to cancer antigen 15-3 (CA 15-3).

METHODS

Plasma levels of tested parameters were determined using enzyme-linked immunosorbent assay (ELISA) while CA 15-3 with chemiluminescent microparticle immunoassay (CMIA).

RESULTS

The plasma levels of VEGF, TIMP-2 showed significantly higher than CA 15-3 values of the diagnostic sensitivity, the predictive values of positive and negative test results (PPV, NPV) and the area under the receiver-operating characteristics (ROC) curve (AUC) in early stages of breast cancer (BC). The combined use of the tested parameters with CA 15-3 resulted in the increase in sensitivity, NPV and AUC, especially in the combination with VEGF (83%; 72%; 0.888) and TIMP-2 (83%; 72%; 0.894). The highest values were obtained for combination of all three parameters (93%; 85%; 0.923).

CONCLUSIONS

These findings suggest the usefulness of the tested parameters in the diagnosis of BC, especially VEGF and TIMP-2 with CA 15-3 in early stages of BC, which could be a new diagnostic panel.

Less is more: low expression of MT1-MMP is optimal to promote migration and tumourigenesis of breast cancer cells

BACKGROUND

Membrane Type-1 Matrix Metalloproteinase (MT1-MMP) is a multifunctional protease implicated in metastatic progression ostensibly due to its ability to degrade extracellular matrix (ECM) components and allow migration of cells through the basement membrane. Despite in vitro studies demonstrating this principle, this knowledge has not translated into the use of MMP inhibitors (MMPi) as effective cancer therapeutics, or been corroborated by evidence of in vivo ECM degradation mediated by MT1-MMP, suggesting that our understanding of the role of MT1-MMP in cancer progression is incomplete.

METHODS

MCF-7 and MDA-MB 231 breast cancer cell lines were created that stably overexpress different levels of MT1-MMP. Using 2D culture, we analyzed proMMP-2 activation (gelatin zymography), ECM degradation (fluorescent gelatin), ERK signaling (immunoblot), cell migration (transwell/scratch closure/time-lapse imaging), and viability (colorimetric substrate) to assess how different MT1-MMP levels affect these cellular parameters. We also utilized Matrigel 3D cell culture and avian embryos to examine how different levels of MT1-MMP expression affect morphological changes in 3D culture, and tumourigenecity and extravasation efficiency in vivo.

RESULTS

In 2D culture, breast cancer cells expressing high levels of MT1-MMP were capable of widespread ECM degradation and TIMP-2-mediated proMMP-2 activation, but were not the most migratory. Instead, cells expressing low levels of MT1-MMP were the most migratory, and demonstrated increased viability and ERK activation. In 3D culture, MCF-7 breast cancer cells expressing low levels of MT1-MMP demonstrated an invasive protrusive phenotype, whereas cells expressing high levels of MT1-MMP demonstrated loss of colony structure and cell fragment release. Similarly, in vivo analysis demonstrated increased tumourigenecity and metastatic capability for cells expressing low levels of MT1-MMP, whereas cells expressing high levels were devoid of these qualities despite the production of functional MT1-MMP protein.

CONCLUSIONS

This study demonstrates that excessive ECM degradation mediated by high levels of MT1-MMP is not associated with cell migration and tumourigenesis, while low levels of MT1-MMP promote invasion and vascularization in vivo.

Anti-elastase, anti-tyrosinase and matrix metalloproteinase-1 inhibitory activity of earthworm extracts as potential new anti-aging agent

OBJECTIVE

To examine whether earthworms of Eisenia fetida, Lumbricus rubellus and Eudrilus eugeniae extracts have elastase, tyrosinase and matrix metalloproteinase-1 (MMP-1) inhibitory activity.

METHODS

The earthworms extract was screened for elastase, tyrosinase and MMP-1 inhibitory activity and compared with the positive controls. It was also evaluated for whitening and anti-wrinkle capacity.

RESULTS

The extract showed significantly (P<0.05) good elastase and tyrosinase inhibition and excellent MMP-1 inhibition compared to N-Isobutyl-N-(4-methoxyphenylsulfonyl)-glycylhydroxamic acid.

CONCLUSIONS

Earthworms extract showed effective inhibition of tyrosinase, elastase and MMP-1 activities. Therefore, this experiment further rationalizes the traditional use of this worm extracts which may be useful as an anti-wrinkle agent.

Normalization of the tumor microenvironment: evidence for tissue inhibitor of metalloproteinase-2 as a cancer therapeutic

Matrix metalloproteinases (MMPs) are members of the Metzincin family of proteases responsible for degrading the extracellular matrix (ECM). In early studies, MMP degradation of the sub-epithelial basement membrane was thought to be tumor cell autonomous and contribute to the invasive behavior of malignant cells. It is now recognized that MMPs have multiple roles that can either promote or inhibit tumor progression and metastasis. The endogenous inhibitors of the MMPs are the tissue inhibitors of metalloproteinases (TIMPs). Early studies on the tumor microenvironment revealed TIMP function to be principally through the inhibition of MMPs, thereby blocking tumor cell migration and invasion. However, data from a number of laboratories are now reporting that TIMPs have direct cellular functions, independent of their MMP inhibitory activity. The TIMPs can modulate normal tissue physiology and development, as well as pathology and progression in a variety of acute and chronic disease states. In this review, we briefly describe the role of MMPs and TIMPs in ECM turnover and formation of the tumor microenvironment. Based on the evidence presented, we postulate that TIMP-2 and other soluble components of the normal ECM may provide a novel therapeutic approach to cancer treatment through "normalization" of the tumor microenvironment.

TIMP-2 modulates cancer cell transcriptional profile and enhances E-cadherin/beta-catenin complex expression in A549 lung cancer cells

Tissue Inhibitor of Metalloproteinase 2 (TIMP-2) plays an essential role in regulating matrix remodeling, cell growth, differentiation, angiogenesis and apoptosis in vitro and in vivo. We have recently shown that TIMP-2-mediated inhibition of tumor growth is independent of matrix metalloproteinase-mediated mechanisms, and is a consequence of modulating both the tumor cells and the tumor microenvironment. In the current study we aim to identify the molecular pathways associated with these effects. We analyzed the transcriptional profile of the human lung cancer cell line A549 upon overexpression of TIMP-2 and Ala+TIMP-2 (mutant that does not inhibit MMP activity), and we found changes in gene expression predominantly related to decreased tumor development and metastasis. Increased E-cadherin expression in response to both TIMP-2 and Ala+TIMP-2 expression was confirmed by real time quantitative RT-PCR and immunoblotting. A549 cells treated with epidermal growth factor (EGF) displayed loss of cobblestone morphology and cell-cell contact, while cells overexpressing TIMP-2 or Ala+TIMP-2 were resistant to EGF-induced morphological changes. Moreover, exogenous treatment with recombinant Ala+TIMP-2 blocked EGF induced down-regulation of E-cadherin. In vivo, immunohistochemistry of A549 xenografts expressing either TIMP-2 or Ala+TIMP-2 demonstrated increased E-cadherin protein levels. More importantly, transcriptional profile analysis of tumor tissue revealed critical pathways associated with effects on tumor-host interaction and inhibition of tumor growth. In conclusion, we show that TIMP-2 promotes an anti-tumoral transcriptional profile in vitro and in vivo, including upregulation of E-cadherin, in A549 lung cancer cells.

Regulation of DCIS to invasive breast cancer progression by Singleminded-2s (SIM2s)

Singleminded-2s (SIM2s) is a member of the bHLH/PAS family of transcription factors and a key regulator of mammary epithelial cell differentiation. SIM2s is highly expressed in mammary epithelial cells and down regulated in human breast cancer. Loss of Sim2s causes aberrant mouse mammary ductal development with features suggestive of malignant transformation, whereas over-expression of SIM2s promotes precocious alveolar differentiation in nulliparous mouse mammary glands, suggesting that SIM2s is required for establishing and enhancing mammary gland differentiation. To test the hypothesis that SIM2s regulates tumor cell differentiation, we analyzed SIM2s expression in human primary breast ductal carcinoma in situ (DCIS) samples and found that SIM2s is lost with progression from DCIS to invasive ductal cancer (IDC). Utilizing a MCF10DCIS.COM progression model, we have shown that SIM2s expression is decreased in MCF10DCIS.COM cells compared to MCF10A cells and reestablishment of SIM2s in MCF10DCIS.COM cells significantly inhibits growth and invasion in vitro and in vivo. Analysis of SIM2s-MCF10DCIS.com tumors showed that SIM2s promoted a more differentiated tumor phenotype including the expression of a broad range of luminal markers (CSN2 (β-casein), CDH1 (E-cadherin), and KER18 (keratin-18)) and suppressed genes associated with stem cell maintenance and a basal phenotype (SMO (smoothened), p63, SLUG (snail-2), KER14 (keratin-14) and VIM (vimentin)). Furthermore, loss of SIM2s expression in MCF10DCIS.COM xenografts resulted in a more invasive phenotype and increased lung metastasis likely due to an increase in hedgehog signaling and matrix metalloproteinase expression. Together, these exciting new data support a role for SIM2s in promoting human breast tumor differentiation and maintaining epithelial integrity.