Suppression of in vivo tumor growth and induction of suspension cell death by tissue inhibitor of metalloproteinases (TIMP)-3

The TIMP protein family: diverse roles in pathophysiology

The tissue inhibitors of matrix metalloproteinases (TIMPs) are a family of four matrisome proteins classically defined by their roles as the primary endogenous inhibitors of metalloproteinases (MPs). Their functions however are not limited to MP inhibition, with each family member harboring numerous MP-independent biological functions that play key roles in processes such as inflammation and apoptosis. Because of these multifaceted functions, TIMPs have been cited in diverse pathophysiological contexts. Herein, we provide a comprehensive overview of the MP-dependent and -independent roles of TIMPs across a range of pathological conditions. The potential therapeutic and biomarker applications of TIMPs in these disease contexts are also considered, highlighting the biomedical promise of this complex and often misunderstood protein family.

Promoter DNA methylation patterns in oral, laryngeal and oropharyngeal anatomical regions are associated with tumor differentiation, nodal involvement and survival

Differentially methylated regions (DMRs) can be used as head and neck squamous cell carcinoma (HNSCC) diagnostic, prognostic and therapeutic targets in precision medicine workflows. DNA from 21 HNSCC and 10 healthy oral tissue samples was hybridized to a genome-wide tiling array to identify DMRs in a discovery cohort. Downstream analyses identified differences in promoter DNA methylation patterns in oral, laryngeal and oropharyngeal anatomical regions associated with tumor differentiation, nodal involvement and survival. Genome-wide DMR analysis showed 2,565 DMRs common to the three subsites. A total of 738 DMRs were unique to laryngeal cancer (n=7), 889 DMRs were unique to oral cavity cancer (n=10) and 363 DMRs were unique to pharyngeal cancer (n=6). Based on the genome-wide analysis and a Gene Ontology analysis, 10 candidate genes were selected to test for prognostic value and association with clinicopathological features. TIMP3 was associated with tumor differentiation in oral cavity cancer (P=0.039), DAPK1 was associated with nodal involvement in pharyngeal cancer (P=0.017) and PAX1 was associated with tumor differentiation in laryngeal cancer (P=0.040). A total of five candidate genes were selected, DAPK1, CDH1, PAX1, CALCA and TIMP3, for a prevalence study in a larger validation cohort: Oral cavity cancer samples (n=42), pharyngeal cancer tissues (n=25) and laryngeal cancer samples (n=52). PAX1 hypermethylation differed across HNSCC anatomic subsites (P=0.029), and was predominantly detected in laryngeal cancer. Kaplan-Meier survival analysis (P=0.043) and Cox regression analysis of overall survival (P=0.001) showed that DAPK1 methylation is associated with better prognosis in HNSCC. The findings of the present study showed that the HNSCC subsites oral cavity, pharynx and larynx display substantial differences in aberrant DNA methylation patterns, which may serve as prognostic biomarkers and therapeutic targets.

Thymoquinone Suppresses Angiogenesis in DEN-Induced Hepatocellular Carcinoma by Targeting miR-1-3p

Hepatocellular carcinoma (HCC) is characterized by its high vascularity and metastasis. Thymoquinone (TQ), the main bio-active constituent of Nigella sativa, has shown anticancer and hepatoprotective effects. TQ's anticancer effect is mediated through miRNA regulation. miR-1-3p plays a significant role in various cancers but its role in HCC invasiveness remains poorly understood. Bio-informatics analysis predicted that the 3'-UTR of TIMP3 is a target for miR-1-3p; Rats were equally divided into four groups: Group 1, the negative control; Group 2 received TQ; Group 3 received DEN; and Group 4 received DEN after pretreatment with TQ. The expression of TIMP3, MMP2, MMP9, and VEGF in rats' liver was determined immunohistochemically. RT-qPCR was used to measure the miR-1-3p level in rats' liver, and TIMP3, MMP2, MMP9, and VEGF in the HepG2 cells after being transfected with miR-1-3p mimic or inhibitor; In rats pretreated with TQ, a decreased expression of MMP2, MMP9 and VEGF, and increased expression levels of TIMP3 and miR-1-3p were detected. Treating the HepG2 cells with miR-1-3p mimic led to the upregulation of TIMP3 and downregulation of MMP2, MMP9, and VEGF, and showed a significant delay in wound healing; These results suggested that the anti-angiogenic effect of TQ in HCC may be mediated through the regulation of miR-1-3p.

Tissue inhibitor of matrix metalloproteinase-3 has both anti-metastatic and anti-tumourigenic properties

TIMP-3 is one of four tissue inhibitors of matrix metalloproteinases, the endogenous inhibitors of the matrix metalloproteinase enzymes. These enzymes have an important role in metastasis, in the invasion of cancer cells through the basement membrane and extracellular matrix. TIMP-1, -2 and -4 both promote and inhibit tumour development, in a context-dependent manner, however TIMP-3 is consistently anti-tumourigenic. TIMP-3 is also the only insoluble member of the family, being either bound to the extracellular matrix or the low density lipoprotein-related protein-1, through which it can be endocytosed. Levels of TIMP-3 have also been shown to be regulated by micro RNAs and promoter hypermethylation, resulting in frequent silencing in many tumour types, to the extent that its expression has been suggested as a prognostic marker in some tumours, being associated with lower levels of metastasis, or better response to treatment. TIMP-3 has been shown to have anti-metastatic effects, both through inhibition of matrix metalloproteinases and ADAM family members and downregulation of angiogenesis. This occurs via interactions with receptors including VEGF, via modulation of signaling pathways and due to protease inhibition. TIMP-3 has also been shown to reduce tumour growth rate, most often by inducing apoptosis by stabilisation of death receptors. A number of successful mechanisms of delivery of TIMP-3 to tumour or inflammatory sites have been investigated in vitro or in animal studies. It may therefore be worthwhile further exploring the use of TIMP-3 as a potential anti-metastatic or anti-tumorigenic therapy for many tumour types.

TIMP-3 as a therapeutic target for cancer

Tissue inhibitor of metalloproteinase-3 (TIMP-3), a secreted glycoprotein, plays an important role in carcinogenesis. It can bind to many proteinases to suppress their activity and thus protect the extracellular matrix from degradation. TIMP-3 may have many anticancer properties, including apoptosis induction and antiproliferative, antiangiogenic, and antimetastatic activities. This review summarizes the structure, proteinase inhibition ability, genetic and epigenetic regulation, cancer therapy potential, and contribution to cancer development of TIMP-3. Furthermore, in this review we discuss its potential as a biomarker for predicting cancer progression and the current state of drugs that target TIMP-3, either alone or in combination with clinical treatment. In conclusion, TIMP-3 can be a biomarker of cancer and a potential target for cancer therapy. This review article can serve as a basis to understand how to modulate TIMP-3 levels as a drug target of cancers.

Tissue inhibitor of metalloproteinase-3 (TIMP3) expression decreases during melanoma progression and inhibits melanoma cell migration

AIMS

Malignant melanoma is the most aggressive form of skin cancer, and metastatic dissemination to regional and visceral sites is responsible for the majority of melanoma-related mortalities. In a recent study by our group, we observed reduced expression of tissue inhibitor of metalloproteinase-3 (TIMP3) in the majority of stage III melanoma samples studied. TIMP3 has been reported as a tumour suppressor in several human malignancies, with reduced expression correlating with poor clinical outcome. In this study, we investigated the changes in TIMP3 expression during melanoma progression.

PATIENTS AND METHODS

TIMP3 expression was analysed by immunohistochemistry in sequential archived tumour material from stage I/II, stage III and stage IV samples from melanoma patients (n = 33). Protein expression was investigated for associations with disease-free survival and overall survival. Methylation status of the gene promoter was determined using methylation-specific PCR. In vitro assays were used to investigate the functional consequences of TIMP3 expression on behavioural aspects of melanoma cells.

RESULTS

We show that TIMP3 expression decreases with melanoma progression although no significant clinical associations were obtained. Analysis of the status of promoter methylation using methylation-specific PCR revealed it to be a low-frequency event in melanoma. Additionally, through gene modulation experiments in melanoma cell lines, we show that TIMP3 negatively regulates cell migration, invasion and anoikis resistance.

CONCLUSIONS

Collectively, our data suggests that TIMP3 functions as a tumour suppressor in melanoma and negatively regulates several aspects of the metastatic cascade.

Biology and clinical management challenges in meningioma

Meningiomas are the most frequently occurring intracranial tumors. They are characterized by a broad spectrum of histopathologic appearance. Molecular alterations driving meningioma development, which affect the NF2 gene, are found in roughly 50% of patients. Rare genetic events in benign meningiomas are mutations in TRAF7, KLF4, AKT1, and SMO; all of these mutations are exclusive of NF2 alterations. Progression to a clinically aggressive meningioma is linked to inactivation of CDKN2A/B genes, and a plethora of signaling molecules have been described as activated in meningiomas, which supports the concept of successful clinical use of specific inhibitors. Established treatments include surgical resection with or without radiotherapy delivered in a single fraction, a few large fractions (radiosurgery), or multiple fractions (fractionated radiotherapy). For recurrent and aggressive tumors, inhibitors of the vascular endothelial growth factor (VEGF) pathway, such as vatalinib, bevacizumab, and sunitinib, showed signs of activity in small, uncontrolled studies, and prospective clinical studies will test the efficacy of the tetrahydroisoquinoline trabectedin and of SMO and AKT1 inhibitors.

Association of TIMP3 expression with vessel density, macrophage infiltration and prognosis in human malignant melanoma

AIMS

Several anti-tumour properties have been ascribed to the tissue inhibitor of matrix metalloproteinases-3 (TIMP3) gene, including inhibition of neovascularisation in tumour xenografts. Reduced protein expression has been linked to promoter hypermethylation and allelic loss of heterozygosity in various human malignancies. In melanoma-positive lymph nodes from patients, we evaluated the association between TIMP3 expression, vessel density, macrophage infiltration and potential correlations with disease-free survival (DFS) and overall survival (OS).

PATIENTS AND METHODS

TIMP3 expression was analysed by immunohistochemistry (IHC) in melanoma lymph node biopsies of stage III melanoma patients (n = 43). Blood vessel density and macrophage infiltration were quantitatively assessed and correlation with TIMP3 expression was investigated. Methylation status of the gene promoter was determined using methylation-specific polymerase chain reaction (MSP). Protein expression and promoter methylation status were investigated for associations with DFS and OS.

RESULTS

Reduced expression of TIMP3, as determined by IHC, was observed in 74% of the cases (32 in 43). A significant inverse correlation was observed between TIMP3 expression and vessel density (p = 0.031). Correlation between TIMP3 expression and macrophage infiltration was not statistically significant (p = 0.369). MSP analysis revealed methylation of the gene promoter in 18% (7 in 38) of the analysed cases. No differences in OS and DFS were observed between cases with high and low TIMP3 expression. Gene promoter methylation was significantly associated with both poor 5-year DFS (p = 0.024) and OS (p = 0.034).

CONCLUSIONS

Our data indicate that TIMP3 is a dominant negative regulator of angiogenesis in cutaneous melanoma and gene silencing by promoter methylation is associated with poor outcome.

Timp3 loss accelerates tumour invasion and increases prostate inflammation in a mouse model of prostate cancer

BACKGROUND

Altered expression and activity of proteases is implicated in inflammation and cancer progression. An important negative regulator of protease activity is TIMP3 (tissue inhibitor of metalloproteinase 3). TIMP3 expression is lacking in many cancers including advanced prostate cancer, and this may facilitate invasion and metastasis by allowing unrestrained protease activity.

METHODS

To investigate the role of TIMP3 in prostate cancer progression, we crossed TIMP3-deficient mice (Timp3(-/-)) to mice with prostate-specific deletion of the tumor suppressor Pten (Pten(-/-)), a well-established mouse model of prostate cancer. Tumor growth and progression were compared between Pten(-/-), Timp3(-/-) and control (Pten(-/-), Timp3(+/+)) mice at 16 weeks of age by histopathology and markers of proliferation, vascularity, and tumor invasion. Metalloproteinase activity within the tumors was assessed by gelatin zymography. Inflammatory infiltrates were assessed by immunohistochemistry for macrophages and lymphocytes whereas expression of cytokines and other inflammatory mediators was assessed by quantitative real time PCR and multiplex ELISA.

RESULTS

Increased tumor growth, proliferation index, increased microvascular density, and invasion was observed in Pten(-/-), Timp3(-/-) prostate tumors compared to Pten(-/-), Timp3(+/+) tumors. Tumor cell invasion in Pten(-/-), Timp3(-/-) mice was associated with increased expression of matrix metalloprotease (MMP)-9 and activation of MMP-2. There was markedly increased inflammatory cell infiltration into the TIMP3-deficient prostate tumors along with increased expression of monocyte chemoattractant protein-1, cyclooxygenase-2, TNF-α, and interleukin-1β; all of which are implicated in inflammation and cancer.

CONCLUSIONS

This study provides important insights into the role of altered protease activity in promoting prostate cancer invasion and implicates prostate inflammation as an important promoting factor in prostate cancer progression.

Timp3 deficient mice show resistance to developing breast cancer

Timp3 is commonly silenced in breast cancer, but mechanistic studies have identified both tumor promotion and suppression effects of this gene. We have taken a genetic approach to determine the impact of Timp3 loss on two mouse models of breast cancer. Interestingly, MMTV-PyMT Timp3^−⁄− mice have delayed tumor onset and 36% of MMTV-Neu Timp3^−⁄− mice remain tumor free. TIMP3 is a regulator of TNF signaling and similar to Timp3, Tnf or Tnfr1 loss delays early tumorigenesis. The tumor suppression in Timp3 null mice requires Tnfr1, but does not result in alterations in the local immune compartment. In the mammary gland, Timps are highly expressed in the stroma and through the transplantation of tumor cells we observe that Timp3 deficiency in the host is sufficient to delay the growth of early, but not advanced tumor cells. Together our data is the first to identify a tumor promoting role of endogenous Timp3 in vivo, the spatial and temporal windows of this effect, and its dependence on Tnfr1.

Knockdown of the AKT3 (PKBγ), PI3KCA, and VEGFR2 genes by RNA interference suppresses glioblastoma multiforme T98G cells invasiveness in vitro

Glioblastoma multiforme (GBM) is the most common primary brain malignancy, having a very poor prognosis and is characterized by extensive brain invasion as well as resistance to the therapy. The phosphoinositide 3-kinase (PI3K)/Akt/PTEN signaling pathway is deregulated in GBM. Besides, florid vascularization and aberrantly elevated vascular endothelial growth factor (VEGF) occur very often. The present study was designed to examine the inhibitory effect of AKT3, PI3KCA, and VEGFR2 small interfering RNAs (siRNAs) on GBM cell invasiveness. T98G cells were transfected with AKT3, PI3KCA, and/or VEGFR2 siRNAs. VEGFR2 protein-positive cells were identified by flow cytometry using specific monoclonal anti-VEGFR2 antibodies. Alterations in messenger RNA (mRNA) expression of VEGF, VEGFR2, matrix metalloproteinases (MMPs) (MMP-2, MMP-9, MMP-13, MMP-14), tissue inhibitors of metalloproteinases (TIMPs) (TIMP-1, TIMP-3), c-Fos, c-Jun, hypoxia-inducible factor-1α (HIF-1α), ObRa, and cathepsin D genes were analyzed by qRT-PCR. Cells treated with specific siRNA were also analyzed for invasion using the Matrigel invasion assay. We have found significantly lower mRNA levels of MMPs, cathepsin D, VEGF, VEGFR2, HIF-1α, and c-Fos/c-Jun ratio, as well as significantly higher mRNA level of TIMPs in AKT3 and PI3KCA siRNA transfected cells compared to untransfected cells, while significantly lower mRNA levels of MMPs (MMP-2, MMP-9, MMP-14) and TIMP-1, as well as significantly higher mRNA level of TIMP-3, were shown only in cells transfected with VEGFR2 siRNA. The positive correlation between MMP-13 and ObRa mRNA copy number has been found. Summarizing, transfection of T98G cells with AKT3, PI3KCA, or VEGFR2 siRNAs leads to a significant reduction in cell invasiveness. The siRNA-induced AKT3, PI3KCA, and VEGFR2 mRNA knockdown may offer a novel therapeutic strategy to reduce the invasiveness of GBM cells.

Epigenetic changes of TIMP-3, GSTP-1 and 14-3-3 sigma genes as indication of status of chronic inflammation and cancer

OBJECTIVES

This study aimed to compare the epigenetic changes via hypermethylation status of TIMP-3, GSTP-1 and 14-3-3σ genes, between healthy subjects and patients with reversible chronic inflammatory disease, and between healthy subjects and patients with irreversible malignant disease, to highlight the genetic changes that occur in the progression from an inflammatory condition to irreversible genetic changes commonly observed in cancer patients.

METHODS

DNA was extracted from the blood of 680 healthy subjects, and tissues and blood of 110 patients with chronic inflammation disease of the gums, as well as neoplastic tissues of 108 breast cancer patients. Methylation-specific polymerase chain reaction (PCR) for TIMP-3, GSTP-1 and 14-3-3σ was performed, and hypermethylation status was analyzed and compared between the 3 groups.

RESULTS

The hypermethylation frequencies of TIMP-3 and GSTP-1 of reversible chronic inflammatory gum disease and the control group were similar, but both were significantly lower than those for malignant disease patients (p<0.0001). The methylation frequency of 14-3-3σ in chronic inflammatory gum disease was higher than in the cancer and control groups (p<0.0001). The methylation of CpG islands in TIMP-3 and GSTP-1 in chronic inflammation patients occurred as frequently as in the control group, but less frequently than in breast cancer patients. However, the epigenetic silencing of 14-3-3σ occurred more frequently in the chronic inflammation group than in cancer patients and healthy controls.

CONCLUSIONS

The epigenetic silencing of 14-3-3σ might be essential for chronic inflammatory gum disease. The epigenetic changes presented in chronic inflammation patients might demonstrate an irreversible destruction in the tissues or organs similar to cancer.

A review of epigenetic and gene expression alterations associated with intracranial meningiomas

OBJECT

A more comprehensive understanding of the epigenetic abnormalities associated with meningioma tumorigenesis, growth, and invasion may provide useful targets for molecular classification and development of targeted therapies for meningiomas.

METHODS

The authors performed a review of the current literature to identify the epigenetic modifications associated with the formation and/or progression of meningiomas.

RESULTS

Several epigenomic alterations, mainly pertaining to DNA methylation, have been associated with meningiomas. Hypermethylation of TIMP3 inactivates its tumor suppression activity while CDKN2 (p14[ARF]) and TP73 gene hypermethylation and HIST1H1c upregulation interact with the p53 regulation of cell cycle control. Other factors such as HOX, IGF, WNK2, and TGF-β epigenetic modifications allow either upregulation or downregulation of critical pathways for meningioma development, progression, and recurrence.

CONCLUSIONS

Genome-wide methylation profiling demonstrated that global hypomethylation correlates with tumor grades and severity. Identification of additional epigenetic changes, such as histone modification and higher-order chromosomal structure, may allow for a more thorough understanding of tumorigenesis and enable future individualized treatment strategies for meningiomas.

Cell surface-bound TIMP3 induces apoptosis in mesenchymal Cal78 cells through ligand-independent activation of death receptor signaling and blockade of survival pathways

Background

The matrix metalloproteinases (MMPs) and their endogenous regulators, the tissue inhibitor of metalloproteinases (TIMPs 1–4) are responsible for the physiological remodeling of the extracellular matrix (ECM). Among all TIMPs, TIMP3 appears to play a unique role since TIMP3 is a secreted protein and, unlike the other TIMP family members, is tightly bound to the ECM. Moreover TIMP3 has been shown to be able to induce apoptotic cell death. As little is known about the underlying mechanisms, we set out to investigate the pro-apoptotic effect of TIMP3 in human mesenchymal cells.

Methodology/Principal Findings

Lentiviral overexpression of TIMP3 in mesenchymal cells led to a strong dose-dependent induction of ligand-independent apoptosis as reflected by a five-fold increase in caspase 3 and 7 activity compared to control (pLenti6/V5-GW/lacZ) or uninfected cells, whereas exogenous TIMP3 failed to induce apoptosis. Concordantly, increased cleavage of death substrate PARP and the caspases 3 and 7 was observed in TIMP3 overexpressing cultures. Notably, activation of caspase-8 but not caspase-9 was observed in TIMP3-overexpressing cells, indicating a death receptor-dependent mechanism. Moreover, overexpression of TIMP3 led to a further induction of apoptosis after stimulation with TNF-alpha, FasL and TRAIL. Most interestingly, TIMP3-overexpression was associated with a decrease in phosphorylation of cRaf, extracellular signal-regulated protein kinase (Erk1/2), ribosomal S6 kinase (RSK1) and Akt and serum deprivation of TIMP3-overexpressing cells resulted in a distinct enhancement of apoptosis, pointing to an impaired signaling of serum-derived survival factors. Finally, heparinase treatment of heparan sulfate proteoglycans led to the release of TIMP3 from the surface of overexpressing cells and to a significant decrease in apoptosis indicating that the binding of TIMP3 is necessary for apoptosis induction.

Conclusion

The results demonstrate that exclusively cell surface-bound endogenous TIMP3 induces apoptosis in mesenchymal Cal78 cells through ligand-independent activation of death receptor signaling and blockade of survival signaling pathways.

Impact of MMP-3 and TIMP-3 gene polymorphisms on prostate cancer susceptibility in North Indian cohort

PURPOSE

Matrix metalloproteinases (MMPs) have been implicated in progression and metastases of different tumors. The balance between the MMPs and their natural inhibitors (tissue inhibitors of matrix metalloproteinases; TIMP) seem to be an important factor related to its role. The purpose of this study was to evaluate polymorphisms in the MMP-3 and TIMP-3 genes for their associations with prostate cancer (PCa) risk in North Indians.

MATERIALS AND METHODS

Genotypes were determined by PCR-RFLP (Polymerase Chain Reaction Restriction Fragment Length Polymorphism) method in 150 PCa patients and 200 age matched controls of similar ethnicity.

RESULTS

We found significant association in the MMP-3(1171)5A/6A and TIMP-3 (1298) C/T polymorphism with PCa risk. Variant genotype (5A/5A) of MMP-3(1171)5A/6A polymorphism had a high PCa risk (p=0.037, OR=3.52, 95%CI=1.08-11.5). Individuals with TIMP-3 (1298) CT genotype as well as T allele showed reduced risk of PCa (p<0.001; OR=0.31; 95%CI=0.18-0.52, and p=0.001; OR=0.49; 95%CI=0.32-0.75). This effect was even more evident in case of T allele carrier (CT+TT) (p<0.001; OR=0.36; 95%CI=0.22-0.59). Overall no significant association was observed statistically in MMP-3 and TIMP-3 with any of the grading stages and smoking habits in PCa. Haplotype analysis of MMP-3 showed that A-5A-A was associated with three folds (OR=3.06; 95%CI=1.71-5.47; p<0.001) increased risk in PCa patients.

CONCLUSION

This is the first reported association between polymorphisms in the MMP-3 and TIMP-3 gene and PCa risk and supports the hypothesis that the protease/antiprotease balance has an important role. Due to the small sample size further investigations need to be done to prove a statistical significant correlation between the MMP/TIMP expression and clinicopathological parameters.

Promoter hypermethylation contributes to TIMP3 down-regulation in high stage endometrioid endometrial carcinomas

AIMS

Expression of tissue inhibitor of metalloproteinases-3 (TIMP-3) has been found to be decreased in several types of cancer by promoter gene hypermethylation. However, little is known regarding the silencing effect of TIMP3 promoter hypermethylation on gene and protein expression in endometrial carcinomas and its prognostic significance.

METHODS AND RESULTS

TIMP3 promoter hypermethylation and gene copy number variations were evaluated using a methylation-specific multiplex ligation-dependent probe amplification approach in 60 cases of endometrioid endometrial carcinomas. TIMP3 expression was also evaluated at the transcript and protein levels. Loss of TIMP-3 protein expression was found in 44 (73%) of 60 carcinomas. Promoter hypermethylation was identified in 25% (15 of 60); was more frequent in stages II-IV (55%, six of 11) than in stage I (18%, nine of 49; P = 0.021); and was found more commonly in tumours with deep myometrial invasion. MLH1 and TIMP3 promoters were hypermethylated simultaneously in the same group of tumours (P < 0.001). A correlation between TIMP3 methylation and microsatellite instability (MSI) was found (P = 0.005). TIMP3 copy number changes were frequently a loss (35%), whereas a gain was detected in only 5%.

CONCLUSIONS

TIMP3 promoter hypermethylation was associated with high stage endometrioid endometrial tumours with extrauterine spread. Nevertheless, promoter hypermethylation and loss of heterozygosity are not the only mechanisms for TIMP3 inactivation.

Multivalent pseudopeptides targeting cell surface nucleoproteins inhibit cancer cell invasion through tissue inhibitor of metalloproteinases 3 (TIMP-3) release

Blockage of the metastasis process remains a significant clinical challenge, requiring innovative therapeutic approaches. For this purpose, molecules that inhibit matrix metalloproteinases activity or induce the expression of their natural inhibitor, the tissue inhibitor of metalloproteinases (TIMPs), are potentially interesting. In a previous study, we have shown that synthetic ligands binding to cell surface nucleolin/nucleophosmin and known as HB 19 for the lead compound and NucAnt 6L (N6L) for the most potent analog, inhibit both tumor growth and angiogenesis. Furthermore, they prevent metastasis in a RET transgenic mice model which develops melanoma. Here, we investigated the effect of N6L on the invasion capacity of MDA-MB-435 melanoma cells. Our results show that the multivalent pseudopeptide N6L inhibited Matrigel invasion of MDA-MB-435 cells in a modified Boyden chamber model. This was associated with an increase in TIMP-3 in the cell culture medium without a change in TIMP-3 mRNA expression suggesting its release from cell surface and/or extracellular matrix. This may be explained by our demonstrated N6L interaction with sulfated glycosaminoglycans and consequently the controlled bioavailability of glycosaminoglycan-bound TIMP-3. The implication of TIMP-3 in N6L-induced inhibition of cell invasion was evidenced by siRNA silencing experiments showing that the loss of TIMP-3 expression abrogated the effect of N6L. The inhibition of tumor cell invasion by N6L demonstrated in this study, in addition to its previously established inhibitory effect on tumor growth and angiogenesis, suggests that N6L represents a promising anticancer drug candidate warranting further investigation.

p38α MAPK mediates 17β-estradiol inhibition of MMP-2 and -9 expression and cell migration in human lovo colon cancer cells

Epidemiological studies demonstrate that the incidence and mortality rates of colorectal cancer in women are lower than in men. However, it is unknown if 17β-estradiol (E(2)) treatment is sufficient to inhibit cell proliferation and cell migration in human colon cancer cells. Up-regulation of urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), and matrix metallopeptidases (MMPs) is reported to associate with the development of cancer cell mobility, metastasis, and subsequent malignant tumor. In the present study, we treated human LoVo colon cancer cells with E(2) to explore whether E(2) down-regulates cell proliferation and migration, and to identify the precise molecular and cellular mechanisms behind the down-regulatory responses. Here, we found that E(2) treatment decreased cell proliferation and cell cycle-regulating factors such as cyclin A, cyclin D1 and cyclin E. At the same time, E(2) significantly inhibited cell migration and migration-related factors such as uPA, tPA, MMP-2, and MMP-9. However, E(2) treatment showed no effects on upregulating expression of plasminogen activator inhibitor-1 (PAI-1), tissue inhibitor of metalloproteinase-1, -2, -3, and -4 (TIMP-1, -2, -3, and -4). After administration of inhibitors including QNZ (NFκB inhibitor), LY294002 (Akt activation inhibitor), U0126 (ERK1/2 inhibitor), SB203580 (p38 MAPK inhibitor) or SP600125 (JNK1/2 inhibitor), E(2) -downregulated cell migration and expression of MMP-2 and MMP-9 in LoVo cells is markedly inhibited only by p38 MAPK inhibitors, SB203580. Application of specific target gene siRNA (ERα, ERβ, p38α, and p38β) to LoVo cells further confirmed that p38 MAPK mediates E(2) /ERs inhibition of MMP-2 and -9 expression and cell motility in LoVo cells. Collectively, these results suggest that E(2) treatment down-regulates cell proliferation by modulating the expression of cyclin A, cyclin D1 and cyclin E. E(2) treatment simultaneously impaired cell migration by inhibiting the expression of uPA, tPA, MMP-2, and MMP-9 through E(2) /ERs - p38α MAPK signaling pathway in human LoVo colon cancer cells.

Tissue inhibitor of metalloproteinases in oral squamous cell carcinomas - a therapeutic target?

Matrix metalloproteinases (MMPs) are proteases responsible for remodeling the extracellular matrix (ECM) and enabling spreading and metastasis of tumor cells, a common phenomenon in oral squamous cell carcinomas (OSCC). They are strongly blocked by several inhibitors, among which we must highlight, for their specificity and potency, the endogenous tissue inhibitors of metalloproteinases (TIMP-1, -2, -3 and -4). The goal of this paper is to describe the expression of TIMPs in OSCC, determining their relation with clinical, histological and prognostic factors, delving into OSCC regulation mechanisms and discussing the use of exogenous TIMPs to treat this type of tumors. Expression of TIMPs in OSCC is higher in tumors than in normal tissue, which correlates with an increase of metastatic risk and regional lymph node affectation. Although some metalloproteinases inhibitors (MMIs) have shown promising results in the treatment of these tumors, their use in OSCC has not been widely tested; and although some indirect MMIs, like COX-2 inhibitors, flavonoids and endostatin seem to have beneficial effects on the invasive capacity of OSCC through regulation of MMPs and TIMP levels, routine clinical use has not been accepted yet.

microRNA-103 regulates the growth and invasion of endometrial cancer cells through the downregulation of tissue inhibitor of metalloproteinase 3

Despite improvements in treatment over the past few decades, endometrial cancer remains one of the most common causes of mortality in women and there is an urgent need for the development of targeted therapies. The aim of this study was to confirm the target gene of miR-103 in human endometrial cancer and investigate the biological functions in which miR-103 is involved through the regulation of the expression of its target gene. This study may provide useful data to gain a better understanding of the effect of miR-103 in tumor formation. miR-103 expression levels were measured using real-time quantitative PCR. The effect of miR-103 on tissue inhibitor of metalloproteinase 3 (TIMP-3) expression was assessed in endometrial cancer cell lines with a miR-103 inhibitor to decrease the level of miR-103 expression. Furthermore, the roles of miR-103 in cell growth and invasion were analyzed using miR-103 inhibitor-transfected cells. The level of expression of miR-103 decreased following transfection with the miR-103 inhibitor. miR-103 inhibitor transfection increased the activity of the luciferase reporter assay containing the TIMP-3 3'-untranslated region (UTR) construct and increased the levels of the TIMP-3 protein but not its mRNA in endometrial cancer cell lines. Finally, miR-103 inhibitor-transfected cells exhibited reduced cell growth and invasive characteristics. Our data suggested that miR-103 post-transcriptionally downregulates the expression of the tumor suppressor TIMP-3 and stimulates growth and invasion in endometrial cancer cell lines. This provides a possible therapeutic target that may upregulate TIMP-3 in endometrial cancer.

The role of EZH2 in the regulation of the activity of matrix metalloproteinases in prostate cancer cells

Degradation of the extracellular matrix (ECM), a critical step in cancer metastasis, is determined by the balance between MMPs (matrix metalloproteinases) and their inhibitors TIMPs (tissue inhibitors of metalloproteinases). In cancer cells, this balance is shifted towards MMPs, promoting ECM degradation. Here, we show that EZH2 plays an active role in this process by repressing the expression of TIMP2 and TIMP3 in prostate cancer cells. The TIMP genes are derepressed by knockdown of EZH2 expression in human prostate cancer cells but repressed by overexpression of EZH2 in benign human prostate epithelial cells. EZH2 catalyzes H3K27 trimethylation and subsequent DNA methylation of the TIMP gene promoters. Overexpression of EZH2 confers an invasive phenotype on benign prostate epithelial cells; however, this phenotype is suppressed by cooverexpression of TIMP3. EZH2 knockdown markedly reduces the proteolytic activity of MMP-9, thereby decreasing the invasive activity of prostate cancer cells. These results suggest that the transcriptional repression of the TIMP genes by EZH2 may be a major mechanism to shift the MMPs/TIMPs balance in favor of MMP activity and thus to promote ECM degradation and subsequent invasion of prostate cancer cells.

JNK suppression is essential for 17β-Estradiol inhibits prostaglandin E2-Induced uPA and MMP-9 expressions and cell migration in human LoVo colon cancer cells

Background

Epidemiological studies demonstrate that the incidence and mortality rates of colorectal cancer in women are lower than in men. However, it is unknown if 17β-estradiol treatment is sufficient to inhibit prostaglandin E2 (PGE2)-induced cellular motility in human colon cancer cells.

Methods

We analyzed the protein expression of urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), matrix metallopeptidases (MMPs), plasminogen activator inhibitor-1 (PAI-1) and tissue inhibitor of metalloproteinases (TIMPs), and the cellular motility in PGE2-stimulated human LoVo cells. 17β-Estradiol and the inhibitors including LY294002 (Akt activation inhibitor), U0126 (ERK1/2 inhibitor), SB203580 (p38 MAPK inhibitor), SP600125 (JNK1/2 inhibitor), QNZ (NFκB inhibitor) and ICI 182 780 were further used to explore the inhibitory effects of 17β-estradiol on PGE2-induced LoVo cell motility. Student's t-test was used to analyze the difference between the two groups.

Results

Upregulation of urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA) and matrix metallopeptidases (MMPs) is reported to associate with the development of cancer cell mobility, metastasis, and subsequent malignant tumor. After administration of inhibitors including LY294002, U0126, SB203580, SP600125 or QNZ, we found that PGE2 treatment up-regulated uPA and MMP-9 expression via JNK1/2 signaling pathway, thus promoting cellular motility in human LoVo cancer cells. However, PGE2 treatment showed no effects on regulating expression of tPA, MMP-2, plasminogen activator inhibitor-1 (PAI-1), tissue inhibitor of metalloproteinase-1, -2, -3 and -4 (TIMP-1, -2, -3 and -4). We further observed that 17β-estradiol treatment inhibited PGE2-induced uPA, MMP-9 and cellular motility by suppressing activation of JNK1/2 in human LoVo cancer cells.

Conclusions

Collectively, these results suggest that 17β-estradiol treatment significantly inhibits PGE2-induced motility of human LoVo colon cancer cells.

Management options in triple-negative breast cancer

Notorious for its poor prognosis and aggressive nature, triple-negative breast cancer (TNBC) is a heterogeneous disease entity. The nature of its biological specificity, which is similar to basal-like cancers, tumors arising in BRCA1 mutation carriers, and claudin-low cancers, is currently being explored in hopes of finding the targets for novel biologics and chemotherapeutic agents. In this review, we aim to give a broad overview of the disease's nomenclature and epidemiology, as well as the basic mechanisms of emerging targeted therapies and their performance in clinical trials to date.

Tissue inhibitor of metalloproteinase-3 (TIMP-3) regulates hematopoiesis and bone formation in vivo

Background

Tissue 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 Findings

We 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/Significance

Our 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.

Hypermethylation and transcriptional downregulation of the TIMP3 gene is associated with allelic loss on 22q12.3 and malignancy in meningiomas

The gene for the tissue inhibitor of metalloproteinase 3 (TIMP3) on 22q12.3 had been reported to be inactivated by promoter methylation in various types of cancers, with controversial findings in meningiomas. We performed direct sodium bisulfite sequencing in a series of 50 meningiomas, including 27 benign meningiomas [World Health Organization (WHO) grade I], 11 atypical meningiomas (WHO grade II) and 12 anaplastic meningiomas (WHO grade III), and found hypermethylation of TIMP3 in 67% of anaplastic meningiomas, but only 22% of atypical and 17% of benign meningiomas. Moreover, TIMP3 methylation scores were significantly inversely correlated with TIMP3 mRNA expression levels (P = 0.0123), and treatment of the meningioma cell line Ben-Men-1 with demethylating agents induced an increased TIMP3 mRNA expression. TIMP3 is located in the chromosomal band 22q12, the allelic loss of which occurs early in meningioma tumorigenesis and preferentially targets the NF2 tumor suppressor gene. In our tumor panel, all meningiomas with TIMP3 hypermethylation--except for a single case--exhibited allelic losses on 22q12.3. Thus, TIMP3 inactivation by methylation seems fairly exclusive to meningiomas with allelic losses on 22q12 but--in contrast to NF2 mutation--appears to be involved in meningioma progression as it is associated with a more aggressive, high-grade meningioma phenotype.

Loss of expression of TIMP3 in clear cell renal cell carcinoma

AIMS

In clear cell renal cell carcinoma (CCRCC), vascular endothelial growth factor (VEGF) represents the central positive mediator of tumour angiogenesis while VEGF receptor (VEGFR) is the primary target of anti-angiogenic therapies. TIMP3 is a physiological VEGFR-2 antagonist and thus could be considered as an anti-angiogenic factor. We therefore determined the status of this physiological inhibitor in CCRCC.

PATIENTS AND METHODS

Archival tumour from 105 patients was studied. TIMP3 expression was analysed using immuno-histochemistry and real-time RT-PCR. Results were correlated with clinicopathological variables. To analyse the mechanisms of gene silencing involved, we performed Multiplex Ligation-dependent Probe Amplification (MLPA) and methylation-specific MLPA (MS-MLPA). At last, we evaluated the main upstream pathway described implicating TGFbetaRII, which induces TIMP3 expression.

RESULTS

A down-expression of TIMP3, determined by immunohistochemistry, affected 100/105 renal cancers (95.2%). TIMP3 mRNA levels were significantly lower in high-grade tumours. Loss of heterozygosity of the TIMP3 gene was observed in 8 tumours (7.6%) and the 5'CpG island of the TIMP3 promoter was found to be methylated in 25 tumours (23.8%). A down-expression of TGFbetaRII was found in 85/105 CCRCCs (80.9%). A significant correlation was found between TIMP3 expression and TGFbetaRII expression.

CONCLUSIONS

This is the first demonstration that the loss of TIMP3 expression is observed in almost all CCRCCs. This loss of expression is a common molecular event in CCRCC. It may be an important initiation step for tumour development in a complex process implicating loss of heterozygosity on chromosome 22q, promoter hyper-methylation and inactivation of the TGFbetaRII pathway.

The tissue inhibitors of metalloproteinases (TIMPs): an ancient family with structural and functional diversity

Tissue inhibitors of metalloproteinases (TIMPs) are widely distributed in the animal kingdom and the human genome contains four paralogous genes encoding TIMPs 1 to 4. TIMPs were originally characterized as inhibitors of matrix metalloproteinases (MMPs), but their range of activities has now been found to be broader as it includes the inhibition of several of the disintegrin-metalloproteinases, ADAMs and ADAMTSs. TIMPs are therefore key regulators of the metalloproteinases that degrade the extracellular matrix and shed cell surface molecules. Structural studies of TIMP-MMP complexes have elucidated the inhibition mechanism of TIMPs and the multiple sites through which they interact with target enzymes, allowing the generation of TIMP variants that selectively inhibit different groups of metalloproteinases. Engineering such variants is complicated by the fact that TIMPs can undergo changes in molecular dynamics induced by their interactions with proteases. TIMPs also have biological activities that are independent of metalloproteinases; these include effects on cell growth and differentiation, cell migration, anti-angiogenesis, anti- and pro-apoptosis, and synaptic plasticity. Receptors responsible for some of these activities have been identified and their signaling pathways have been investigated. A series of studies using mice with specific TIMP gene deletions has illuminated the importance of these molecules in biology and pathology.

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.

Tumor-associated MICA is shed by ADAM proteases

The immunoreceptor NKG2D promotes immunosurveillance of malignant cells and protects the host from tumor initiation by activating natural killer cells and costimulating CD8 T cells. NKG2D-mediated recognition of malignant cells by cytotoxic lymphocytes is enabled through the tumor-associated expression of NKG2D ligands (NKG2DL) resulting from cellular or genotoxic stress. Shedding of NKG2DL is thought to constitute a major countermechanism of tumor cells to subvert NKG2D-mediated immunosurveillance. Here, we report that the prototypical NKG2DL MICA is released by proteolytic cleavage in the stalk of the MICA ectodomain, where deletions, but not alanine substitutions, impede MICA shedding. Small compound-mediated stimulation and inhibition of MICA shedding adduced characteristics that indicated an involvement of members of the "a disintegrin and metalloproteinase" (ADAM) family. Accordingly, MICA shedding by tumor cells was inhibited by silencing of the related ADAM10 and ADAM17 proteases, which are known to promote tumor growth by releasing epidermal growth factor receptor ligands. Collectively, our data show that ADAM10 and ADAM17 are critically involved in the tumor-associated proteolytic release of soluble MICA facilitating tumor immune escape. Hence, therapeutic blockade of ADAM10 and ADAM17 seems promising for cancer treatment by targeting both growth and immune escape of tumors.

Tissue inhibitors of metalloproteinases in cell signaling: metalloproteinase-independent biological activities

Over the past 20 years, the tissue inhibitors of metalloproteinases (TIMPs) have been implicated in direct regulation of cell growth and apoptosis. However, the mechanisms of these effects have been controversial. Recent work by several laboratories has identified specific signaling pathways and cell surface binding partners for members of the TIMP family. TIMP-2 binding to the integrin alpha(3)beta(1) is the first description of a cell surface receptor for a TIMP family member. TIMP-2 has been shown to induce gene expression, to promote G(1) cell cycle arrest, and to inhibit cell migration. TIMP-1 binding to CD63 inhibits cell growth and apoptosis. These new findings suggest that TIMPs are multifunctional and can act either directly through cell surface receptors or indirectly through modulation of protease activity to direct cell fate. The emerging concept is that TIMPs function in a contextual fashion so that the mechanism of action depends on the tissue microenvironment.

DNA methylation in hepatocellular carcinoma

As for many other tumors, development of hepatocellular carcinoma (HCC) must be understood as a multistep process with accumulation of genetic and epigenetic alterations in regulatory genes, leading to activation of oncogenes and inactivation or loss of tumor suppressor genes (TSG). In the last decades, in addition to genetic alterations, epigenetic inactivation of (tumor suppressor) genes by promoter hypermethylation has been recognized as an important and alternative mechanism in tumorigenesis. In HCC, aberrant methylation of promoter sequences occurs not only in advanced tumors, it has been also observed in premalignant conditions just as chronic viral hepatitis B or C and cirrhotic liver. This review discusses the epigenetic alterations in hepatocellular carcinoma focusing DNA methylation.

[Assessment of tissue inhibitor of metalloproteinases-2 (TIMP-2) in laryngeal cancer]

Metalloproteinases are the proteolytic enzymes that digest components of the extracellular matrix in many physiological and pathological conditions. Their activity is regulated by their natural inhibitors: non-specific alpha2-macroglobulin and specific tissue inhibitors of metalloproteinases (TIMP). There are four TIMPs. TIMP-2 is the only enzyme that is expressed in constitutive manner and has the ability to inhibit activity of all metalloproteinases. TIMP-2 has been identified in many carcinomas including cancers of lung, oral cavity, breast and colon. There was correlation between TIMP-2 expression and clinical course of the disease observed in most of the neoplasm.

AIM

The aim of the research was to evaluate the expression of TIMP-2 in laryngeal cancer and to assess the prognostic significance of this factor.

MATERIAL AND METHOD

104 patients with laryngeal cancer, that underwent surgical treatment were included in the study. Only cases with at least a 5-year follow-up were included. Immunohistochemical studies were performed on formalin fixed, paraffin embedded sections by using monoclonal antibodies against TIMP-2 antigen and ABC detection system.

RESULTS

TIMP-2 expression was cytoplasmatic, mainly in cancer cells, but also in some stromal cells. There was correlation between TIMP-2 expression and tumor size and grading observed. We didn't find any correlation between TIMP-2 and nodal metastases, recurrence and survival.

CONCLUSIONS

Our results don't suggest that TIMP-2 expression may be used as a prognostic factor in patients with laryngeal cancer. Nevertheless there are more researches needed to explain the role of TIMPs in growth and progression of neoplastic tumors.

Methylation of TIMP3 in esophageal squamous cell carcinoma

AIM: To measure the frequency of DNA methylation of the tissue inhibitor of metalloproteinase 3 (TIMP3) promoter and relate this to any change of gene expression in esophageal squamous cell carcinoma in patients from a region of high incidence in China.

METHODS: Cancer cell lines were treated with or without the demethylating reagent 5-aza-2’-deoxycytidine. Methylation of the TIMP3 promoter was assessed in three regions by melt curve analysis and its expression was assessed by real-time RT-PCR. Tumors and proximal resection margins were obtained from 64 patients with esophageal squamous cell carcinoma from a region of high incidence in China. Methylation was assessed by melt curve analysis and expression by immunohistochemistry.

RESULTS: Methylation in one of the three promoter regions assessed correlated with gene silencing in esophageal cell lines. A degree of methylation of TIMP3 was found in only four esophageal squamous cell carcinomas, and partial loss of TIMP3 protein expression in just one.

CONCLUSION: Methylation and loss of expression of TIMP3 occurs infrequently in esophageal squamous cell carcinoma in a region of high incidence in China.

Tissue inhibitor of metalloproteinases-3 promoter methylation is an independent prognostic factor for bladder cancer

PURPOSE

TIMP-3 (tissue inhibitor of metalloproteinases-3) is 1 of 4 members of a family of proteins that were originally classified according to their ability to inhibit matrix metalloproteinases. We analyzed TIMP-3 methylation in 175 urine sediment DNA samples from patients with bladder cancer with well characterized clinicopathological parameters, including patient outcome.

MATERIALS AND METHODS

We examined urine sediment DNA for aberrant methylation of 9 genes, including TIMP-3, by quantitative fluorogenic real-time polymerase chain reaction.

RESULTS

Using an optimal cutoff value by TaqMan(R) quantitation we found that the risk of death was statistically significantly higher in patients with higher TIMP-3 and ARF methylation (HR 1.99, 95% CI 1.12 to 3.27, p = 0.01 and HR 1.66, 95% CI 1.00 to 2.76, p = 0.05, respectively) than in patients without/lower TIMP3 and ARF methylation in urine. A significant correlation was also seen between the risk of death and stage 3 tumor (HR 2.73, 95% CI 1.58 to 4.72, p = 0.003) and metastasis (HR 3.32, 95% CI 1.98 to 5.57, p = 0.0001). Multivariate analysis subsequently revealed that TIMP-3 methylation was an independent prognostic factor for bladder cancer survival with stage and metastasis (p = 0.001 and 0.02, respectively).

CONCLUSIONS

These results suggest that TIMP-3 promoter methylation could be a clinically applicable marker for bladder cancer progression.

Prognostic significance of matrix metalloproteinases-1, -2, -7 and -13 and tissue inhibitors of metalloproteinases-1, -2, -3 and -4 in colorectal cancer

Strong expression of many matrix metalloproteinases (MMPs) has been related to poor survival of colorectal cancer (CRC) patients. The expression of tissue inhibitors of metalloproteinases (TIMPs) has been associated with both a beneficial and a poor outcome and there is thus a need to further clarify the significance of MMPs and TIMPs in CRC. The prognostic significance of 4 MMPs and TIMPs in CRC was evaluated. Formalin-fixed, paraffin-embedded tissue arrayed samples of 351 patients with primary colon or rectal cancer of Dukes' stages A-D were selected for immunohistochemical staining of MMP-1, -2, -7 and -13, and TIMP-1, -2, -3 and -4. High expression of MMP-2 in the malignant epithelium as well as in the surrounding stroma was associated with reduced survival of colon cancer patients. Strong epithelial and stromal cytoplasmic staining of TIMP-3 was associated with a longer survival in rectal cancer patients, and here the interobserver variation for evaluating the degree of staining was lower than for epithelial staining. Strong stromal cytoplasmic staining of TIMP-4 predicted longer survival of rectal cancer patients. Multivariate analysis showed that stromal cytoplasmic TIMP-3 staining was the only marker of independent prognostic value. MMP-2 might be a useful prognostic marker in colon cancer, and TIMP-3 and TIMP-4 in rectal cancer, but the findings associated with stromal staining should be interpreted with some caution. Different biologic behavior or different genetic development may explain the differences between colon and rectal cancers regarding the expression of MMP-2, TIMP-3 and TIMP-4.

Promoter hypermethylation of RASSF1A and RUNX3 genes as an independent prognostic prediction marker in surgically resected non-small cell lung cancers

Aberrant methylation of promoter CpG islands is known to be a major inactivation mechanism of the tumor suppressor and tumor-related genes. Some published studies suggest a relationship to exist between the methylation status of several genes and the prognosis in non-small cell lung cancer (NSCLC); hypermethylation of the specific genes may be expected to serve as a biomarker for the prognosis, after a curative resection of NSCLC. To determine the relationship between the methylation status of the tumor suppressor and the tumor-related genes, and the clinicopathologic characteristics, including the survival rate, in patients with NSCLC after a surgical resection, we studied methylation in 10 genes (DAPK, FHIT, H-cadherin, MGMT, p14, p16, RAR-beta, RASSF1A, RUNX3, and TIMP-3) in 101 NSCLC cases by methylation-specific PCR (MSP). The methylation frequencies of the 10 genes examined in NSCLC were 26% for DAPK, 34% for FHIT, 26% for H-cadherin, 14% for MGMT, 8% for p14, 27% for p16, 38% for RAR-beta, 42% for RASSF1A, 25% for RUNX3, and 12% for TIMP-3. Clinicopathologically, the patients with all stages of disease who had positive RASSF1A, RUNX3, or H-cadherin methylation status were found to have a significantly shorter duration of survival, as compared with the patients with a negative methylation status for those genes (RASSF1A:P=0.023, RUNX3:P=0.035, H-cadherin:P=0.039) in univariate analysis. Thereafter, while limiting our examination to patients with stage I disease, the patients who had a positive RASSF1A or RUNX3 methylation status were found to have a significantly shorter duration of survival, in comparison to the patients with negative methyaltion status for each of those genes (RASSF1A:P=0.022, RUNX3:P<0.01) in univariate analysis. Next, the histological differences were recognized that the patients with RUNX3 methylation had a shorter duration of survival in adenocarcinomas (ACs) (P=0.045), in contrast to those with RASSF1A methylation who had a shorter duration of survival in squamous cell carcinomas (SCCs) (P=0.021). In multivariate analysis, both positive RASSF1A methylation status, and positive RUNX3 methylation status were found to be independent prognostic factors (RASSF1A:P=0.031, RUNX3:P=0.028), as was TNM stage (P=0.004) and pleural involvement (P=0.037). In conclusion, the hypermethylation of RASSF1A or RUNX3 gene is therefore a useful biomarker to predict the prognosis in NSCLC, particularly RASSF1A due to SCCs and RUNX3 due to ACs.

Immunohistochemical changes in vulnerable rat brain regions after reversible global brain ischaemia

Human global ischaemia was simulated in adult rats by inducing 20 min brain ischaemia and 60 min post-ischaemic recirculation. Immunohistochemical expression of MMP-9, TIMP-3, Bax and Bcl-2, and DNA fragmentation (with the TUNEL reaction) were investigated. The morphological data showed different neuronal responses in the hippocampus compared with the cerebral and cerebellar cortices. MMP-9 immunoreactivity was different in the hippocampus, particularly in dentate gyrus and the CA1 region, compared with these cortices. Negative TIMP-3 staining in ischaemic hippocampal neurons may indicate a loss of its inhibitory activity on MMP-9 that could enhance cell death. Bcl-2 down regulation, Bax positivity and TUNEL+ type II cells in the dentate gyrus granular layer could be responsible for induction of apoptotic death in CA1 hippocampal pyramidal cells via loss of fibre input. Results suggest differential behaviours of neural cells after 60 min reperfusion.

Expression of tissue inhibitor of metalloproteinase-3 (TIMP-3) and its prognostic significance in resected non-small cell lung cancer

BACKGROUND AND OBJECTIVES

Tissue inhibitor of metalloproteinase-3 (TIMP-3) inhibits the activity of metalloproteinases that play important roles in development and progression of malignant tumors. We conducted a retrospective study of TIMP-3 expression in resected non-small cell lung cancer (NSCLC).

METHODS

TIMP-3 expression was examined immunohistochemically in primary tumor specimens from 143 patients who underwent complete resection for NSCLC. Correlations between TIMP-3 expression grade and tumor histology, TNM classification, MMP-2 and MMP-9 expression grade, VEGF expression grade, intra-tumoral microvessel density, proliferative index, apoptosis index, and prognosis were analyzed.

RESULTS

TIMP-3 expression was low in 40, moderate in 71, and high in 32 patients. Higher TIMP-3 expression was seen in squamous cell carcinoma than in adenocarcinoma (P = 0.001), and reduced TIMP-3 expression was significantly associated with nodal involvement (P = 0.016) and advanced pathologic stage (P = 0.036). MMP-2 expression was reduced along with enhanced TIMP-3 expression (P = 0.010). The 5-year overall survival rates of low, moderate, and high TIMP-3 patients were 53, 64, and 84%, respectively (P = 0.037). Multivariate analysis confirmed that enhanced TIMP-3 expression was an independent factor for a favorable prognosis (P = 0.037).

CONCLUSIONS

TIMP-3 expression status was significantly correlated with pathologic stage and nodal involvement, and was an independent prognostic factor in resected NSCLC.

Matrix metalloproteinases: influence on smooth muscle cells and atherosclerotic plaque stability

Atherosclerotic plaque rupture, with subsequent occlusive thrombosis, is the underlying cause of most cases of sudden cardiac death. Matrix metalloproteinases (MMPs) are thought to mediate the progression of stable atherosclerotic lesions to an unstable phenotype that is prone to rupture through the destruction of strength-giving extracellular matrix (ECM) proteins. Smooth muscle cells secrete and deposit ECM proteins and are, therefore, considered protective against atherosclerotic plaque destabilization. However, similar to inflammatory cells (e.g., macrophages), smooth muscle cells release numerous MMPs that are capable of digesting ECM proteins. Thus, the interaction of smooth muscle cells and MMPs in atherosclerotic plaques is complex and not fully understood. Recently, research into the roles of MMPs and their endogenous inhibitors (tissue inhibitors of metalloproteinases), and their effects on smooth muscle behavior during plaque destabilization has been aided by the development of reproducible animal models of plaque instability. A plethora of studies has demonstrated that MMPs directly modulate smooth muscle behavior with both beneficial and deleterious effects on atherosclerotic plaque stability, in addition to their canonical effects on ECM remodeling. Consequently, broad-spectrum MMP inhibition may inhibit plaque-stabilizing mechanisms, such as smooth muscle cell growth, while conversely retarding ECM destruction and subsequent rupture. Hence the development of selective MMP inhibitors, that spare inhibitory effects on smooth muscle cell function, may be useful therapies to prevent plaque rupture and in this regard MMP-12 appears to be a particularly attractive target.

[The role of matrix metalloproteinases and tissue inhibitors of metalloproteinases in invasion of tumours of neuroepithelial tissue]

Tumour invasion requires degradation of extracellular matrix components and migration of cells through degraded structures into surrounding tissues. Matrix metalloproteinases (MMP) constitute a family of zinc and calcium-dependent endopeptidases that play a key role in the breakdown of extracellular matrix, and in processing of cytokines, growth factors, chemokines and cell surface receptors. Their activity is regulated at the levels of transcription, activation and inhibition by tissue inhibitors of metalloproteinases (TIMP). Changes in expression of MMP and TIMP are implicated in tumour invasion, because they may contribute to both migration of tumour cells and angiogenesis. Alterations of MMP expression observed in brain tumours arouse interest in the development and evaluation of synthetic matrix metalloproteinase inhibitors as antitumour agents.

Expression of tissue inhibitor of matrix metalloproteinases (TIMP)-3 protein in invasive breast carcinoma: relation to tumor phenotype and clinical outcome

Introduction

Our aim was to study the expression pattern of tissue inhibitor of metalloproteinases (TIMP)-3 protein in invasive breast carcinoma, and its clinicopathological and prognostic value as well as its relation to markers indicative of the tumor phenotype.

Methods

Immunohistochemistry was performed on paraffin-embedded tissue specimens from 173 invasive breast carcinomas to detect the proteins TIMP-3, estrogen receptor (ER), progesterone receptor, p53, c-erbB-2, topoisomerase IIα and Bcl-2.

Results

TIMP-3 protein was immunodetected in the cytoplasm of the malignant cells and the peritumoral stroma, as well as in in situ carcinoma and normal epithelium. Reduced expression of TIMP-3 protein within cancer cells was correlated with carcinomas of high nuclear and histological grade (p = 0.032 and p = 0.015, respectively), and low ER expression (p = 0.053). Moreover, TIMP-3 immunopositivity was inversely correlated with the expression of p53 and topoIIα proteins (p = 0.002 and p = 0.008, respectively), whereas it was positively associated with Bcl-2 expression (p = 0.020). Reduced expression of TIMP-3 protein within cancer cells was found to have an unfavorable impact on disease-free survival (p = 0.052) in the entirety of the patient population, as well as in both subgroups of lymph-node-positive and mutant-p53-negative patients (p = 0.007 and p = 0.037, respectively). Stromal localization of TIMP-3 protein was found to have no clinicopathological or prognostic value.

Conclusion

This is the first immunohistochemical study to show that TIMP-3 protein within cancer cells is associated with tumor phenotype. Reduced expression of TIMP-3 protein within cancer cells was found to correlate with an aggressive tumor phenotype, negatively affecting the disease-free survival of both subgroups of lymph node-positive and mutant-p53-negative patients.

Anoikis-resistant MDCK cells carrying susceptibilities to TNF-alpha and verotoxin that are suitable for influenza virus cultivation

Madin-Darby canine kidney (MDCK) cells were originally anchorage-dependent epithelial cells. Here, we have isolated a novel MDCK-derived cell population, termed 6 M-4, by means of culturing MDCK cells in suspension for nearly 6 months in the presence of Streptomyces griseus metalloendopeptidase (MEP). The isolated cells showed unique proliferation characteristics, which differed from parental MDCK cells. They proliferated adherently on a polystyrene matrix, but proliferated non-adherently both in the presence of MEP and on a non-adhesive matrix coated with poly 2-methacryloyloxyethyl phosphorylcholine (MPC). The 6 M-4 cells consisted of at least two cell types. One type, termed 6 M-4-TR7, would not grow in soft agar and showed a novel phenotype in that the cells were susceptible to both TNF-alpha and verotoxin 1 (VT1). In addition, the isolated adhesion-independent cells sustained epithelial traits of parental MDCK cells. We further show that these MDCK-derivative cells are suitable for influenza virus cultivation. Hemagglutination (HA) titers of influenzaviruses A and B were increased in the suspension culture of 6 M-4-TR7 cells supplemented with the MEP in comparison to adherently growing cells in the presence of trypsin.

Tissue inhibitor of metalloproteinase-3 differentially binds to components of Bruch's membrane

BACKGROUND

Sorsby's fundus dystrophy (SFD) is caused by mutations in tissue inhibitor of metalloproteinase (TIMP)-3 and, with the exception of early onset, is similar to age-related macular degeneration. The pathological features of this condition relate to the accumulation of TIMP-3 in Bruch's membrane.

AIMS

To compare the extracellular membrane-binding characteristics of wild-type and four SFD-mutant TIMP-3s.

METHODS

COS-7 cells were transfected with wild-type, Ser-181, Gly-167, Ser-156 and Tyr-168 SFD-mutant TIMP-3 cDNA. The TIMP-3 proteins subsequently synthesised were harvested, analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, semiquantified by ELISA and used in binding assays on the basis of the retention of the wild-type and SFD-mutant TIMP-3 proteins by components of Bruch's membrane.

RESULTS

SFD-mutant TIMP-3s could not be distinguished from wild-type TIMP-3 by the extents to which they aggregated or adhered to type-I collagen, type-IV collagen, fibronectin, laminin, elastin, chondroitin sulphates A, B and C, and heparin sulphate. Of these macromolecules, the wild-type and SFD-mutant TIMP-3s exhibited greatest affinity for elastin and laminin.

CONCLUSION

The similarity in the physical and extracellular membrane-binding characteristics of wild-type and SFD-mutant TIMP-3s indicates that these properties are not responsible for the difference in timing of onset of SFD and age-related macular degeneration.

Tissue inhibitor of metalloproteinase-3 induces apoptosis in prostate cancer cells and confers increased sensitivity to paclitaxel

Prostate cancer is the most common cancer and the second leading cause of cancer-related death in American men. To investigate the possible usefulness of tissue inhibitor of metalloproteinase-3 (TIMP-3) in prostate cancer gene therapy, we used an adenovirus expressing TIMP-3 to assess its role as an apoptosis trigger in highly metastatic prostate cancer cell lines PC-3 and DU-145. We showed that TIMP-3 alone induced apoptotic cell death which was triggered by mitochondrion-mediated caspase-3 activation. In combination treatment, we found that adenovirus-mediated expression of TIMP-3 greatly sensitised prostate cancer cells to chemotherapeutic drug paclitaxel, indicating a superadditive or synergistic effect of TIMP-3 and cytostatic treatment on prostate cancer cell death. The proper combination of adenovirus-mediated expression of TIMP-3 with conventional chemotherapeutic drug(s) could have potential benefits in treating highly metastatic prostate cancer.

Novel functions of TIMPs in cell signaling

Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases (MMPs) and the balance between MMPs/TIMPs regulates the extracellular matrix (ECM) turnover and remodeling during normal development and pathogenesis. Increasing evidence indicates a much more complex role for TIMPs during tumor progression and angiogenesis, in addition to their regulation of MMP-mediated ECM degradation. In this article, we review both the MMP-dependent and -independent actions of TIMPs for the regulation of cell death, cell proliferation, and angiogenesis, with a particular emphasis on TIMP-1 in the regulation of tetraspanin/integrin-mediated cell survival signal transduction pathways.

Targeting ADAM-mediated ligand cleavage to inhibit HER3 and EGFR pathways in non-small cell lung cancer

We describe here the existence of a heregulin-HER3 autocrine loop, and the contribution of heregulin-dependent, HER2-mediated HER3 activation to gefitinib insensitivity in non-small cell lung cancer (NSCLC). ADAM17 protein, a major ErbB ligand sheddase, is upregulated in NSCLC and is required not only for heregulin-dependent HER3 signaling, but also for EGFR ligand-dependent signaling in NSCLC cell lines. A selective ADAM inhibitor, INCB3619, prevents the processing and activation of multiple ErbB ligands, including heregulin. In addition, INCB3619 inhibits gefitinib-resistant HER3 signaling and enhances gefitinib inhibition of EGFR signaling in NSCLC. These results show that ADAM inhibition affects multiple ErbB pathways in NSCLC and thus offers an excellent opportunity for pharmacological intervention, either alone or in combination with other drugs.

RhoA and RhoC proteins promote both cell proliferation and cell invasion of human oesophageal squamous cell carcinoma cell lines in vitro and in vivo

There is growing evidence that Rho proteins are deregulated by overexpression in tumours; and according to some reports, this correlates with disease progression. Our previous clinical study had demonstrated a correlation between RhoA expression and tumour progression in oesophageal squamous cell carcinoma (ESCC). These findings prompted us to study, using nude mice, pathological roles of Rho proteins in human ESCC cells. Western blot analysis in ESCC cell lines, in addition to cell proliferation and in vitro migration assays, were performed to observe the malignant potential of RhoA and RhoC in untransfected and transfected cells. Constitutively active RhoA, RhoC and dominant negative RhoA (dnRhoA) proteins were transfected to ESCC (TE-1 and TE-2) cells. The stably transfected cells were injected into nude mice, and the growth and metastasis of these cells to the lungs were analysed. Tumour tissues were then examined using immunohistochemical methods for proteins Ki-67 (MIB-1), FAK, MMP-1, MMP-9 and TIMP-3. Protein levels of RhoA and RhoC in ESCC cell lines were visualised by Western blotting, and showed highest expression in TE-2 cells. Results from the migration assay illustrated that both RhoA and RhoC play a role in migration of ESCC cells. In TE-2 transfected cells, RhoC showed greater migration compared to RhoA. By using an experimental metastasis model in nude mice, RhoA was found to promote more tumour growth than RhoC, whereas RhoC induced lung metastasis in comparison to RhoA. Ki-67 labelling index was used to evaluate the proliferation potential of tumour tissue inoculated from nude mice. In TE-2 cells RhoA gave a proliferation capacity of 24.8+/-0.5, which was significantly higher than those of TE-2 RhoC 10+/-0.4 (P<0.01). Strong immunoreactivity for FAK, MMP-1 and MMP-9 proteins was present in all tumour cells. By contrast, loss of TIMP-3 expression was observed in all tumour cells. In conclusion, our results indicate that pro-oncogenic Rho proteins are involved in promoting tumour growth, cell migration and metastasis in human ESCC cells in nude mice. The results from this study suggest that active Rho proteins may induce a transforming effect that leads to a malignant phenotype.

Keratoconus: Matrix metalloproteinase-2 activation and TIMP modulation

Keratoconus is an ocular condition that causes corneal thinning, cone formation and scarring. In view of a hypothesis that activated MMP-2 may initiate or facilitate disease progression, the MMP-2/TIMP systems of stromal cells derived from normal and keratoconic corneas have been compared. To achieve this, stromal cell cultures were established from normal, clear keratoconic (KCS-1) and scarred keratoconic (KCS-2) corneas. The secreted MMP-2 was assayed using [(3)H]Type IV collagen and analysed by zymography. Optimally maintained and nutrient deprived cells were subsequently incubated with [(3)H]lysine. The secreted radiolabelled macromolecules were separated and quantified. The results obtained indicated that optimally maintained KCS-1 stromal cells produced more MMP-2 than normal stromal cells but not TIMP. Nutrient deprivation induced MMP-2 activation and cell death. Surviving cells upregulated TIMP-1 synthesis and in this respect became similar to the KCS-2 stromal cells that did not excessively generate activated MMP-2 or die as a consequence of nutrient deprivation. From these results, it was concluded that KCS-1 stromal cells over-expressed MMP-2 without increasing TIMP production. This may facilitate MMP-2 activation in vivo and hence advance the keratoconic condition. KCS-2 cultures over-expressed both MMP-2 and TIMP-1. Because TIMP-1 inhibits MMP-2 activity and protects against cell death it may be of significance in initiating repair processes and curtailing keratoconus.

TIMP-3 deficiency in the host, but not in the tumor, enhances tumor growth and angiogenesis

Tumor cells, stromal cell compartment and the extracellular matrix (ECM) together generate a multifaceted tumor microenvironment. Matrix metalloproteinases and their tissue inhibitors (TIMPs) provide a means for tumor-stromal interaction during tumorigenesis. Among TIMPs, TIMP-3 is uniquely localized to the ECM and is frequently silenced in human cancers. Here, we asked whether the absence of TIMP-3 in the tumor cell or the host affects the process of tumorigenesis. Timp-3(-/-) ES-cell clones were generated and used to develop teratomas in nude mice. Timp-3(-/-) teratomas showed similar tumor take, growth, and angiogenesis compared to timp-3(+/+) teratomas. To study the effect of TIMP-3 ablation in the host stroma, we measured the growth kinetics of subcutaneous B16F10 melanomas in timp-3(-/-) and wild-type littermates. Tumors grew significantly faster in timp-3(-/-) than in wild-type mice and their CD31 content was significantly higher indicating increased angiogenesis. Augmented angiogenesis in timp-3(-/-) mice was directly tested using Matrigel plug and Gelfoam assays. In response to FGF-2, timp-3(-/-) endothelial cells invaded more efficiently, leading to enhanced formation of functional blood vessels. Thus, TIMP-3 deficiency in the host, but not in the tumor per se, leads to enhanced tumor growth and angiogenesis. TIMP-3 located within the tumor microenvironment inhibits tumorigenesis.