Tissue Inhibitor Of Metalloproteinases-1 Overexpression Research Articles

Opposite effects of tissue inhibitor of metalloproteinases-1 (TIMP-1) over-expression and knockdown on colorectal liver metastases

BackgroundTissue inhibitors of metalloproteinases (TIMPs) and the corresponding metalloproteinases are integral parts of the protease network and have been shown to be involved in cancer development and metastasis. Paradoxically, for TIMP-1, tumor promoting as well as tumor inhibitory effects have been observed.MethodsTo address this paradox, we utilized the BALB/c/CT26 mouse model that reliably leads to liver metastasis after splenic tumor cell injection and variegated the type of target cells for therapeutic intervention and the modalities of gene transfer. Since we have observed before that over-expression of TIMP-1 in liver host cells leads to efficient tumor growth inhibition in this model, we now examined whether targeting the tumor cells themselves will have a similar effect.ResultsIn concordance with the earlier results, TIMP-1 over-expression in tumor cells led to a dramatic reduction of tumor growth as well. To evaluate any influence of treatment modality, we further examined whether TIMP-1 knockdown in the same animal model would have the opposite effect on tumor growth than TIMP-1 over-expression. Indeed, TIMP-1 knockdown led to a marked increase in tumor burden.ConclusionThese data indicate that in the BALB/c/CT26 model, the modification of TIMP-1 has concordant effects irrespective of the type of target cell or the technique of modulation of TIMP-1 activity, and that TIMP-1 is unequivocally tumor inhibitory in this model.

P4-01-17: TIMP-1 Over-Expression Confers Resistance of MCF-7 Breast Cancer Cells to Fulvestrant.

Abstract Background Endocrine resistance represents a major challenge in the management of estrogen receptor (ER) positive breast cancer. Currently no predictive biomarkers for endocrine resistance in ERpositive breast cancer patients are in clinical use. In a clinical study, patients with metastatic breast cancer and high levels of serum Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) had less benefit from endocrine therapy than patients with a lower level of serum TIMP-1 [1]. Therefore, we evaluated the association between TIMP-1 and response to endocrine therapy using an in vitro approach. We have previously presented initial results on TIMP-1 and response to endocrine therapy [2]. Materials and Methods: MCF-7 cells were stably transfected with pcDNA3.1(Hyg)-TIMP-1 plasmid, and a panel of 11 subclones with different expression levels of TIMP-1 was generated. TIMP-1 expression levels were confirmed using enzyme-linked immunosorbent assay (ELISA). Four subclones with high or low TIMP-1 expression were analyzed for the growth response to estrogen, 4-hydroxytamoxifen and fulvestrant. These four subclones were analyzed for protein expression by western blotting. All subclones were analyzed by whole human genome oligo microarrays 4×44K for determination of gene expression levels. Data were analyzed using the limma R/Bioconductor package. Paired-end Solexa sequencing was applied to selected subclones with high and low TIMP-1 levels to identify transcriptomic changes. Results: High expression of TIMP-1 was associated with resistance to fulvestrant, whereas growth response to either estrogen or 4-hydroxytamoxifen was independent of TIMP-1 expression levels. High expression of TIMP-1 protein and mRNA was associated with undetectable levels of progesterone receptor (PgR) protein and mRNA whereas ER protein and mRNA levels were unaffected by TIMP-1. To characterize the potential role of TIMP-1 in estrogen signaling we analyzed the expression of reported estrogen-responsive genes and no general change was observed. We identified genes that correlated positively or negatively to TIMP-1 expression. Among the identified genes was PgR, which is a direct target for ER. Conclusion: Our data suggest that a high expression of TIMP-1 in vitro is associated with resistance to fulvestrant but not to 4-hydroxytamoxifen. Estrogen-regulated genes are not generally affected by changes in TIMP-1 expression levels and therefore TIMP-1 appears to affect endocrine resistance through other mechanisms than globally regulating ER signaling. However, high expression of TIMP-1 is associated with loss of PgR and this may be related to the resistance towards fulvestrant.

P4-09-26: Prognostic Significance of Tissue Inhibitor of Metalloproteinase-1 (TIMP-1) in Breast Cancer.

Abstract Background: Despite advances of systemic treatment in breast cancer guided by hormonal status and HER2 amplification, new prognostic and predictive factors are still warranted to optimize treatments among these patients. Tissue Inhibitor of Metalloproteinase-1 (TIMP-1), a physiologic inhibitor of Matrix Metalloproteinases (MMPs), can act in both pro- and anti-tumoral effects. The prognostic significance of TIMP-1 in breast cancer is still controversial. This study aims to determine the prognostic significance of TIMP-1 in breast cancer. Material and Methods: One-hundred and seventy-six primary breast cancers from women with early stage disease treated with standard adjuvant therapy were analyzed by gene expression microarrays and immunohistochemistry for TIMP-1. Immunohistochemical analysis was independently reviewed by two pathologists. Results: At the optimized cut-off point, patients with high TIMP-1 RNA levels had a significantly shorter time to relapse, with a hazard ratio (HR) of 1.6 (p = 0.039), but without significant differences in overall survival (HR 1.29, p = 0.37). Although cytoplasmic overexpression of TIMP-1 protein was not correlated with early relapse (HR 1.2, p = 0.35), high expression was associated with shorter overall survival (HR 1.73, p = 0.027). In multivariate analysis, when considering stage, histologic grade, hormonal and HER2 status, TIMP-1 RNA levels remained independently prognostic for early relapse (HR 1.68, p = 0.04). Discussion: Elevated TIMP-1 RNA levels are independently prognostic for early recurrence, whereas protein overexpression of TIMP-1 is correlated with short overall survival in primary breast cancer. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-26.

Overexpression of Tissue Inhibitor of Metalloproteinase 3 in Macrophages Reduces Atherosclerosis in Low-Density Lipoprotein Receptor Knockout Mice

Tissue inhibitor of metalloproteinase 3 (TIMP3) is a stromal protein that inhibits the activity of proteases and receptors. TIMP3 is downregulated in metabolic and inflammatory disorders, such as type 2 diabetes mellitus and atherosclerosis, particularly in regions enriched with monocyte/macrophage cells. To investigate the role of TIMP3 in atherosclerosis, we generated a new mouse model in which Timp3 was overexpressed in the atherosclerotic plaque via a macrophage-specific promoter (MacT3). We elucidated any potential antiatherosclerotic effects of TIMP3, including regulation of monocyte/macrophage recruitment within atherosclerotic plaques, in MacT3 mice crossbred with low-density lipoprotein receptor knockout (LDLR(-/-)) mice. MacT3/LDLR(-/-) mice had an improvement of atherosclerosis and metabolic parameters compared with LDLR(-/-). En face aorta and aortic root examination of MacT3/LDLR(-/-) mice revealed smaller atherosclerotic plaques with features of stability, such as increased collagen content and decreased necrotic core formation. Atherosclerotic plaques in MacT3/LDLR(-/-) mice contained fewer T cells and macrophages. Furthermore, TIMP3 overexpression in macrophages resulted in reduced oxidative stress signals, as evidenced by lower lipid peroxidation, protein carbonylation, and nitration in atheromas. Our study confirmed that macrophage-specific overexpression of TIMP3 decreases the inflammatory content and the amplitude of atherosclerotic plaques in mice.

Sustained Reduction of Vein Graft Neointima Formation by Ex Vivo TIMP-3 Gene Therapy

Coronary artery vein graft failure, resulting from thrombosis, intimal thickening, and atherosclerosis, is a significant clinical problem, with approximately 50% of vein grafts failing within 10 years. Intimal thickening is caused by migration of vascular smooth muscle cells from the media to the intima, where they proliferate. Interventions using gene transfer to inhibit vascular smooth muscle cells proliferation and migration are attractive because ex vivo access to the graft is possible. The involvement of matrix-degrading metalloproteinases in intimal thickening is well established, and we previously showed that adenoviral-delivered overexpression of an endogenous inhibitor, the tissue inhibitor of metalloproteinases-3 (TIMP-3), significantly retarded intimal thickening in short-term autologous porcine arteriovenous interposition grafts (28 days). However, it is essential to determine whether this approach will provide longer-term benefits. We assessed whether a recombinant adenovirus that overexpresses TIMP-3 (RAdTIMP-3) affects vein graft intimal thickening in the longer term (at 3 months). Porcine saphenous veins were subjected to luminal infection with 2.5×10(10) pfu/mL RAdTIMP-3 or RAd60 (control virus) or vehicle control, for 30 minutes before implantation into the carotid artery. Analysis of grafts harvested 3 months after delivery revealed that RAdTIMP-3-infected grafts had significantly reduced intimal areas compared with both controls (3.2 ± 0.4 mm(2) versus 5.6 ± 0.7 mm(2) and 5.9 ± 0.5 mm(2), RAdTIMP-3, RAd60, and vehicle, respectively). Medial areas were also significantly decreased by TIMP-3 (3.8 ± 0.3 mm(2) versus 6.7 ± 1.0 mm(2) and 5.2 ± 0.4 mm(2), RAdTIMP-3, RAd60, and vehicle, respectively). Overexpression of TIMP-3 provides a sustained retardation of vein graft intimal thickening and highlights the translational potential for ex vivo TIMP-3 gene therapy.

Tissue Inhibitor of Metalloproteinase-1 Promotes NIH3T3 Fibroblast Proliferation by Activating p-Akt and Cell Cycle Progression

Tissue inhibitor of metalloproteinase-1 (TIMP-1) plays various roles in cell growth in different cell types. However, few studies have focused on TIMP-1's effect on fibroblast cells. In this study, we investigated the effects of TIMP-1 overexpression on NIH3T3 fibroblast proliferation and potential transduction signaling pathways involved. Overexpression of TIMP-1, by transfection of the pLenti6/V5-DESTTIMP-1 plasmid, significantly promoted NIH3T3 proliferation as determined by the BrdU array. Neither 5 nor 15 nM GM6001 (matrix metalloproteinase system inhibitor) affected NIH3T3 proliferation, but 45 nM GM6001 inhibited proliferation. TIMP-1 overexpression activated the p-Akt pathway, but not the p-ERK or p-p38 pathway. In TIMP-1-transfected cells, cyclinD1 was upregulated and p21CIP1 and p27(KIP1) were downregulated, which promoted cell entry into the S and G2/M phases. The PI3-K inhibitor LY294002 abolished the TIMP-1-induced effects. Overexpression of intracellular TIMP-1 stimulated NIH3T3 fibroblast proliferation in a matrix metalloproteinase (MMP)-independent manner by activating the p-Akt pathway and related cell cycle progression.

TIMP‐3 promotes apoptosis in nonadherent small cell lung carcinoma cells lacking functional death receptor pathway

Tissue inhibitor of metalloproteinases-3 (TIMP-3) has previously been identified as a tumor suppressor for adherent malignant and normal cells. TIMP-3 inhibits adhesion of cells to extracellular matrix and promotes apoptosis through death receptor-activated, caspase-8-mediated pathway. Here, we have studied the effect of adenovirally mediated overexpression of TIMP-3 on small cell lung cancer (SCLC) cell lines SW2 and N417, which grow in suspension and lack functional caspase-8. The results show that adenoviral delivery of TIMP-3 promotes apoptotic cell death in SCLC cells in the absence of caspase-8 activation. These results suggest TIMP-3 as a promising therapeutic anticancer protein also in nonadherent malignant cells lacking functional death receptor signaling.

TIMP-3 recruits quiescent hematopoietic stem cells into active cell cycle and expands multipotent progenitor pool

Regulating transition of hematopoietic stem cells (HSCs) between quiescent and cycling states is critical for maintaining homeostasis of blood cell production. The cycling states of HSCs are regulated by the extracellular factors such as cytokines and extracellular matrix; however, the molecular circuitry for such regulation remains elusive. Here we show that tissue inhibitor of metalloproteinase-3 (TIMP-3), an endogenous regulator of metalloproteinases, stimulates HSC proliferation by recruiting quiescent HSCs into the cell cycle. Myelosuppression induced TIMP-3 in the bone marrow before hematopoietic recovery. Interestingly, TIMP-3 enhanced proliferation of HSCs and promoted expansion of multipotent progenitors, which was achieved by stimulating cell-cycle entry of quiescent HSCs without compensating their long-term repopulating activity. Surprisingly, this effect did not require metalloproteinase inhibitory activity of TIMP-3 and was possibly mediated through a direct inhibition of angiopoietin-1 signaling, a critical mediator for HSC quiescence. Furthermore, bone marrow recovery from myelosuppression was accelerated by over-expression of TIMP-3, and in turn, impaired in TIMP-3-deficient animals. These results suggest that TIMP-3 may act as a molecular cue in response to myelosuppression for recruiting dormant HSCs into active cell cycle and may be clinically useful for facilitating hematopoietic recovery after chemotherapy or ex vivo expansion of HSCs.

Tissue Inhibitor of Metalloproteinase-3 (TIMP-3) Regulates Hematopoiesis and Bone Formation In Vivo

BackgroundTissue inhibitor of metalloproteinases-3 (TIMP-3) inhibits matrix metalloproteinases and membrane-bound sheddases. TIMP-3 is associated with the extracellular matrix and is expressed in highly remodeling tissues. TIMP-3 function in the hematopoietic system is unknown.Methodology/Principal FindingsWe now report that TIMP-3 is highly expressed in the endosteal region of the bone marrow (BM), particularly by osteoblasts, endothelial and multipotent mesenchymal stromal cells which are all important cellular components of hematopoietic stem cell (HSC) niches, whereas its expression is very low in mature leukocytes and hematopoietic stem and progenitor cells. A possible role of TIMP-3 as an important niche component was further suggested by its down-regulation during granulocyte colony-stimulating factor-induced mobilization. To further investigate TIMP-3 function, mouse HSC were retrovirally transduced with human TIMP-3 and transplanted into lethally irradiated recipients. TIMP-3 overexpression resulted in decreased frequency of B and T lymphocytes and increased frequency of myeloid cells in blood and BM, increased Lineage-negative Sca-1+KIT+ cell proliferation in vivo and in vitro and increased colony-forming cell trafficking to blood and spleen. Finally, over-expression of human TIMP-3 caused a late onset fatal osteosclerosis.Conclusions/SignificanceOur results suggest that TIMP-3 regulates HSC proliferation, differentiation and trafficking in vivo, as well as bone and bone turn-over, and that TIMP-3 is expressed by stromal cells forming HSC niches within the BM. Thus, TIMP-3 may be an important HSC niche component regulating both hematopoiesis and bone remodeling.

TIMP3: a physiological regulator of adult myogenesis

Myogenic differentiation in adult muscle is normally suppressed and can be activated by myogenic cues in a subset of activated satellite cells. The switch mechanism that turns myogenesis on and off is not defined. In the present study, we demonstrate that tissue inhibitor of metalloproteinase 3 (TIMP3), the endogenous inhibitor of TNFalpha-converting enzyme (TACE), acts as an on-off switch for myogenic differentiation by regulating autocrine TNFalpha release. We observed that constitutively expressed TIMP3 is transiently downregulated in the satellite cells of regenerating mouse hindlimb muscles and differentiating C2C12 myoblasts. In C2C12 myoblasts, perturbing TIMP3 downregulation by overexpressing TIMP3 blocks TNFalpha release, p38 MAPK activation, myogenic gene expression and myotube formation. TNFalpha supplementation at a physiological concentration rescues myoblast differentiation. Similarly, in the regenerating soleus, overexpression of TIMP3 impairs release of TNFalpha and myogenic gene expression, and delays the formation of new fibers. In addition, downregulation of TIMP3 is mediated by the myogenesis-promoting microRNA miR-206. Thus, TIMP3 is a physiological regulator of myogenic differentiation.

Abstract 4651: Elevated serum tissue inhibitor of metalloproteinases-1 (TIMP-1) level predicts shorter survival in ovarian cancer

Abstract Body: Background: Matrix metalloproteinases (MMPs) play a key role in invasion and metastasis of cancer cells. MMPs are able to degrade extracellular matrix and aid formation of new blood vessels, thus supporting metastatic tumor growth and angiogenesis. The MMP family can be regulated by their inhibitors, the tissue inhibitor of metalloproteinases (TIMPs), which bind MMPs noncovalently. TIMP-1 has paradoxical multifunctional roles in tumorigenesis, independent of its original MMP-inhibitory role: growth promotion, inhibition of apoptosis, and regulation of angiogenesis. Overexpression of TIMP-1 confers resistance to chemotherapy in cell culture, and increased TIMP-1 has been associated with an unfavorable prognosis in multiple cancer types. TIMP-1 has recently been reported to be a predictive biomarker in large human breast cancer trials. The purpose of this study was to determine the correlation between serum TIMP-1 levels at the time of diagnosis in patients with ovarian cancer and correlate this biomarker with overall survival. Methods: Serum TIMP-1 was assayed from 36 patients diagnosed with ovarian cancer between 1982 and 1987. Blood was collected at the time of diagnosis and serum frozen. Serum TIMP-1 levels were measured using a TIMP-1 ELISA from Oncogene Science / Siemens Healthcare Diagnostics (Cambridge, MA). Clinical outcome data were correlated with serum TIMP1 levels. Results: TIMP-1 levels from 36 patients had a mean of 559 ng/ml with SD of + 296 (range 145 to 1460 ng/ml). 35 of 36 patients had clinical follow up data available. 82.14% of patients had distant metastasis, 7.14 % had localized tumor, and 10.71 % had regional involvement. Elevated serum TIMP-1 level predicted shorter survival in ovarian cancer by quartile analysis (p=0.022). Median survival was 4079 days for patients with the lowest serum TIMP-1 quartile, and 106 days for those with the highest serum TIMP-1 quartile. On a continuous basis, higher serum TIMP-1 trended to predict significant shorter survival (p=0.063). Conclusions: Elevated serum TIMP-1 levels at the time of diagnosis predicted shorter survival in ovarian cancer. Circulating TIMP-1 deserves further study as a predictive and prognostic factor in ovarian cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4651.

Down-regulation of Tissue Inhibitor of Metalloproteinase-3 (TIMP-3) Expression Is Necessary for Adipocyte Differentiation

Matrix metalloproteinase activity is essential for proper extracellular matrix remodeling that takes place during adipose tissue formation. Four tissue inhibitors of matrix metalloproteinases (TIMPs) regulate their activity. However, the role of TIMPs in adipocyte differentiation is poorly understood. We found that the expression of all TIMPs was modified during adipocyte differentiation, but that of TIMP-3 was distinguished by its extreme down-regulation. TIMP-3 expression was closely linked to the differentiation process. Indeed, it remained low during the adipocyte differentiation but increased when cell differentiation was prevented. We identified the transcription factor Sp1 as being responsible for the regulation of TIMP-3 expression during adipocyte differentiation. Overexpression of TIMP-3 reduced adipocyte differentiation, underlining its active role in this process. TIMP-3 overexpression decreased the expression of the early and obligate key inductors of adipogenesis Krüppel-like factor 4 (Klf4), early growth response 2 (Egr2/Krox20), and CAAT/enhancer-binding protein beta (C/EBPbeta). Our results indicate that during preadipocyte differentiation, the Sp1-dependent decrease in TIMP-3 expression is required for the successful implementation of the adipocyte differentiation program.

A New Role for TIMP-1 in Modulating Neurite Outgrowth and Morphology of Cortical Neurons

BackgroundTissue inhibitor of metalloproteinases-1 (TIMP-1) displays pleiotropic activities, both dependent and independent of its inhibitory activity on matrix metalloproteinases (MMPs). In the central nervous system (CNS), TIMP-1 is strongly upregulated in reactive astrocytes and cortical neurons following excitotoxic/inflammatory stimuli, but no information exists on its effects on growth and morphology of cortical neurons.Principal FindingsWe found that 24 h incubation with recombinant TIMP-1 induced a 35% reduction in neurite length and significantly increased growth cones size and the number of F-actin rich microprocesses. TIMP-1 mediated reduction in neurite length affected both dendrites and axons after 48 h treatment. The effects on neurite length and morphology were not elicited by a mutated form of TIMP-1 inactive against MMP-1, -2 and -3, and still inhibitory for MMP-9, but were mimicked by a broad spectrum MMP inhibitor. MMP-9 was poorly expressed in developing cortical neurons, unlike MMP-2 which was present in growth cones and whose selective inhibition caused neurite length reductions similar to those induced by TIMP-1. Moreover, TIMP-1 mediated changes in cytoskeleton reorganisation were not accompanied by modifications in the expression levels of actin, βIII-tubulin, or microtubule assembly regulatory protein MAP2c. Transfection-mediated overexpression of TIMP-1 dramatically reduced neuritic arbour extension in the absence of detectable levels of released extracellular TIMP-1.ConclusionsAltogether, TIMP-1 emerges as a modulator of neuronal outgrowth and morphology in a paracrine and autrocrine manner through the inhibition, at least in part, of MMP-2 and not MMP-9. These findings may help us understand the role of the MMP/TIMP system in post-lesion pre-scarring conditions.

Inhibition of tumor growth and induction of apoptosis in prostate cancer cell lines by overexpression of tissue inhibitor of matrix metalloproteinase-3

The destruction of extracellular matrix by matrix metalloproteinases is a key event in cancer progression. The tissue inhibitors of metalloproteinases can restrain tumor growth by inhibiting these enzymes. We sought to determine whether overexpression of tissue inhibitor of metalloproteinase-3 (TIMP-3) could suppress the malignant phenotype of human prostate cancer cell line PC-3M. Stable overexpression of TIMP-3 inhibited cell proliferation significantly by MTT assay. Both early and late apoptosis were observed in TIMP-3 overexpressing cells, and flow cytometry analysis showed S-phase blocking of the cell cycle. Monolayer invasion assay and transwell invasion assay showed significantly decreased invasive potential in TIMP-3 overexpressing cells compared with control cells. Cell adhesion and motility were also lower after TIMP-3 was overexpressed. In vivo, cells stably overexpressing TIMP-3 completely lost the ability to form tumors after injection into nude mice. Transfection of TIMP-3 into established tumors by electroporation also had a significant antitumor effect. TIMP-3-treated tumor tissues had significant apoptosis by TUNEL assay. These results showed that overexpression of TIMP-3 inhibits invasion and proliferation of prostate cancer cells in vitro and inhibits tumor growth in vivo. The experiments suggest a potential use for TIMP-3 in the gene therapy of prostate cancer.

Adenovirus carrying TIMP-3: A potential tool for cervical cancer treatment

Objective. Previous studies have demonstrated the pivotal roles of matrix metalloproteinases (MMPs) in cervical cancer progression. Tissue inhibitor of metalloproteinases-3 (TIMP-3) can inhibit all of MMPs, and its overexpression can retard many kinds of tumor growth. Especially, a potent bystander effect would make it to be more advisable for treating cervical cancer whose primary growth pattern is to invade adjacent structures. These characters prompted the authors to explore its further applicability in human cervical cancer. Methods. We constructed a replication deficient adenoviral vector carrying TIMP-3 (Ad-TIMP-3). It was transferred into different cervical cancer cell lines in vitro and was injected into the tumor xenografts of nude mice in vivo. Results. Overexpression of TIMP-3 by adenovirus vector arrested cervical cancer cells in G 2/M phase. It also promoted growth inhibition of cancer cells by bystander effects. Ad-TIMP-3 infection produced a more potent cell killing effect than Ad-p53 ( P < 0.05). A synergic effect was observed when Ad-TIMP-3 and cisplatin (cDDP) were used in combination ( D < 1). In vivo, Ad-TIMP-3 could inhibit cervical cancer xenografts growth. Compared with Ad-TIMP-3 and cDDP groups, tumor growth in Ad-TIMP-3 combined with cDDP group was inhibited more significantly ( P < 0.05). Conclusion. These findings indicated that Ad-TIMP-3 bear a therapeutic potential for cervical cancer.

In vitro susceptibility to the pro-apoptotic effects of TIMP-3 gene delivery translates to greater in vivo efficacy versus gene delivery for TIMPs-1 or -2

Matrix metalloproteinases (MMPs) are essential for extracellular matrix (ECM) breakdown and repair, and have been implicated in the development of metastases. TIMP-3 was initially identified as a potent inhibitor of MMPs, however it also has several properties that are unique and not related to its ability to abrogate MMPs. We studied the effects of overexpression of tissue inhibitor of metalloproteinases-3 (TIMP-3) on lung cancer cells and explored the mechanisms involved in apoptosis-induction in susceptible cells and subsequently, the therapeutic effect in vivo. Overexpression of TIMP-3 resulted in apoptosis of A549 lung cancer cells and AdCMVTIMP3 up-regulated the expression of p53, Fas ligand, TNFR1 and TNFR2 on these cells. Adenoviral delivery of TIMP-3 gene inhibited the growth of pre-established A549 tumours in Balb/c nude mice, and was associated with a greater therapeutic effect than either TIMP-1 or -2 gene delivery. There was no evidence of increased hepatic toxicity following the delivery of TIMP-3 either from intra-tumoural or intravenous injection. Thus, at least in cells showing in vitro susceptibility, TIMP-3 gene therapy offers a therapeutic advantage over TIMPs 1 and 2. These findings establish the potential of adenoviral gene delivery of TIMP3 as a therapeutic agent for selected lung cancers.

A microarray study to characterize the molecular mechanism of TIMP-3-mediated tumor rejection

Glial cell invasion is a multistep cellular process that involves a complex system of tightly regulated proteases (matrix metalloproteinases; MMPs) and their endogenous inhibitors (tissue inhibitors of metalloproteinases; TIMPs) to mediate the degradation of the basement membrane and extracellular matrix. Tissue inhibitor of metalloproteinases-3 (TIMP-3) is a matrix-bound inhibitor of MMPs. In the present study, we have overexpressed the TIMP3 gene in human glioma cells with a herpes simplex virus type 1 amplicon-based vector. Oligonucleotide DNA arrays were employed to identify genes that were differentially modulated by the overexpression of TIMP-3. Consistent with the function of TIMP-3, genes associated with angiogenesis, growth factors, cytokines, death receptors, and substrates of the various MMPs were found to be up-regulated. Furthermore, caspases are important in the signaling pathway of cellular apoptosis, and the overexpression of TIMP-3 in glioma cells is tightly associated with the activation of caspases, including caspase-1, at both the mRNA level (P=0.0371) and the protein level. Moreover, the activation of an apoptotic pathway via the overexpression of TIMP-3 induced apoptosis of transduced human glioma cells in vitro and the growth inhibition of human glioma tumor xenografts in immunodeficient mice.

Tissue inhibitor of metalloproteinase 1 (TIMP-1) promotes plasmablastic differentiation of a Burkitt lymphoma cell line: implications in the pathogenesis of plasmacytic/plasmablastic tumors

AbstractTissue inhibitor of metalloproteinase 1 (TIMP-1) is a stromal factor with multiple functions. Overexpression of TIMP-1 correlates with aggressive clinical behavior of a spectrum of tumors. Here, for the first time, we address the role of TIMP-1 in the pathogenesis of B-cell lymphomas. An Epstein-Barr virus (EBV)-negative Burkitt lymphoma cell line with ectopic TIMP-1 expression (TIMP-1JD38) was used to identify genes induced/repressed by TIMP-1. Differentially expressed genes were analyzed by cDNA microarray, and they were validated by immunohistochemistry, flow cytometry, and Western blotting. Analysis revealed changes of genes coding for B-cell growth/differentiation, transcription, and cell cycle regulators. TIMP-1 repressed expression of germinal center (GC) markers CD10, Bcl-6, PAX-5 and up-regulated plasma cell-associated antigens CD138, MUM-1/IRF-4, XBP-1, and CD44, suggesting a plasma cell differentiation. This is accompanied by activation of signal transducer and activator of transcription 3 (STAT-3) and switch to cyclin D2 expression. However, TIMP-1JD38 cells expressed an inactive form of XBP-1, lacking antibody production/secretion. This incomplete plasmacytic differentiation occurs without altering cell proliferation, and despite c-Myc deregulation, indicating an arrested plasmacytic/plasmablastic stage of differentiation. Further validation in human lymphoma cell lines and in primary B-cell tumors demonstrated a predominant TIMP-1 expression in tumors with plasmacytic/plasmablastic phenotypes, including multiple myelomas. These findings strongly support TIMP-1 as an important factor in the pathogenesis of plasmacytic/plasmablastic tumors. (Blood. 2005;105:1660-1668)

A quantitative in vitro model of smooth muscle cell migration through the arterial wall using the human amniotic membrane.

The development of intimal hyperplasia involves smooth muscle cell (SMC) migration into the intima and proliferation. Matrix metalloproteinases and their tissue inhibitors play important roles in this process. In this study, we describe a novel in vitro model for studying SMC migration through the vessel wall. Human aortic SMCs (hASMCs) labeled with 125I-iododeoxyuridine or unlabeled were grown on the stromal aspect of the human amniotic membrane. Mechanical damage to endothelial cells grown on the basement membrane and addition of growth factors or platelets were characterized for their effect on SMC migration into the stroma both by histological methods and by measuring the radioactivity associated with the membrane after removal of noninvasive SMCs. To assess the reliability of the model, the cells were infected with a recombinant adenovirus encoding the tissue inhibitor of metalloproteinase-1 (TIMP-1). Addition of a platelet-derived growth factor gradient stimulated hASMC infiltration into the stroma. This effect was abolished with TIMP-1-transduced hASMC, confirming that TIMP-1 overexpression blocks SMC invasion of the stroma. This in vitro model of SMC migration in the vessel wall provides an inexpensive, quantitative, and reliable tool to study the molecular and cellular mechanisms of intimal hyperplasia.

Tissue inhibitor of metalloproteinases-1 (TIMP-1) inhibits tumor growth and angiogenesis in the TIMP-1 transgenic mouse model.

The tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) has been recognized as a multifunctional protein. The role of TIMPs in cancer remains the subject of conflicting reports with an antitumor activity or a tumor growth stimulation activity by several mechanisms. The aim of our study is to investigate the effect of ectopic TIMP-1 overexpression on the primary transplanted tumor growth. We employed transgenic mice overexpressing the human TIMP-1 (hTIMP-1) in the liver under control of the albumin promoter/enhancer (TIMP-Tg-mice) and producing high serum levels of TIMP-1. We used the transplantable Ehrlich tumor cells in the current study. The allograft study revealed that the tumor growth in the TIMP-Tg-mice was more significantly inhibited than control (Cont) mice by associated suppression of neovascularization in the tumor. The in vitro studies showed that the recombinant TIMP-1 (rTIMP-1) did not affect the proliferation of the endothelial cells (ECs) and tumor cells, suggesting that the tumor suppressive effect of TIMP-1 was not due to cytotoxicity. TIMP-1 significantly inhibited EC tubular formation in vitro. Furthermore, TIMP-1 treatment did not affect the levels of matrix metalloproteinase (MMP)-2 and MMP-9 mRNA in the Ehrlich tumor cells in vitro, although these expressions in the tumor were markedly suppressed in the TIMP-Tg-mice, compared to the Cont-mice at the end of the experiment. These results suggested that the ectopically overexpressed TIMP-1 inhibited the tumor growth by angiogenesis suppression.