Sequential production and activation of matrix-metalloproteinase-9 (MMP-9) with breast cancer progression

Migration and invasion of NSCLC suppressed by the downregulation of Src/focal adhesion kinase using single, double and tetra domain anti- CEACAM6 antibodies

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Overexpression of CEACAM 6 involved in the development of non-small cell lung cancer.

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Anti-CEACAM 6 antibodies with different valences can be used to target CEACAM 6 overexpressing tumor cells.

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Tetravalent sdAb (4Ab) showed significant effect on cell viability.

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High affinity anti-CEACAM 6 antibodies potentially inhibited migration via src/FAK pathway.

Carcinoembryonic antigen-related cell adhesion molecules 6 (CEACAM6) is a cell adhesion receptor. Expression of CEACAM6 in non-small cell lung cancer (NSCLC) associated with tumor progression and metastatic condition via Src/FAK signaling pathway. We established three anti-CEACAM6 antibodies with valences, which were designed to be monomeric sdAb, bivalent sdAb (2Ab), and tetravalent sdAb (4Ab). The anti-CEACAM6 antibodies can be used to target CEACAM6 overexpressing NSCLC. Anti-CEACAM6 antibodies, sdAb, 2Ab and 4Ab, were modified with different valency via protein engineering. sdAb and multivalent sdAbs (2Ab & 4Ab) were expressed and purified from E.coli and CHO cells, respectively. We compared the effect of anti-CEACAM6 antibodies with doxorubicin in NSCLC cell line both in vitro and in vivo. The 4Ab showed significant effect on cell viability. In addition, A549 cells treated with 2Ab and 4Ab inhibited the invasion and migration. In western blot, the 2Ab and 4Ab showed significant inhibition of phospho FAK domain Ty397 that is essential for activation of Src kinase family. Meanwhile, overall protein analysis revealed that 2Ab and 4Ab potently inhibited the phosphorylation of pSRC, pERK, pFAK, pAKT, MMP-2, MMP-9 and N-cadherin. Anti-tumor effect was observed in an A549 NSCLC xenograft model treated with 2Ab or 4Ab compared with doxorubicin. Confocal analysis showed higher targeting ability of 4Ab than that of 2Ab at 4 h incubation. Our data suggests that 2Ab and 4Ab inhibits EMT-mediated migration and invasion via suppression of Src/FAK signaling, which exhibits therapeutic efficiency for NSCLC treatment.

Everolimus Inhibits the Progression of Ductal Carcinoma In Situ to Invasive Breast Cancer Via Downregulation of MMP9 Expression

PURPOSE

We evaluated the role of everolimus in the prevention of ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) progression.

EXPERIMENTAL DESIGN

The effects of everolimus on breast cancer cell invasion, DCIS formation, and DCIS progression to IDC were investigated in a 3D cell culturing model, intraductal DCIS xenograft model, and spontaneous MMTV-Her2/neu mouse model. The effect of everolimus on matrix metalloproteinase 9 (MMP9) expression was determined with Western blotting and IHC in these models and in patients with DCIS before and after a window trial with rapamycin. Whether MMP9 mediates the inhibition of DCIS progression to IDC by everolimus was investigated with knockdown or overexpression of MMP9 in breast cancer cells.

RESULTS

Everolimus significantly inhibited the invasion of human breast cancer cells in vitro. Daily intragastric treatment with everolimus for 7 days significantly reduced the number of invasive lesions from intraductal DCIS foci and inhibited DCIS progression to IDC in the MMTV-Her2/neu mouse mammary tumor model. Mechanistically, everolimus treatment decreased the expression of MMP9 in the in vitro and in vivo models, and in breast tissues from patients with DCIS treated with rapamycin for 1 week. Moreover, overexpression of MMP9 stimulated the invasion, whereas knockdown of MMP9 inhibited the invasion of breast cancer cell-formed spheroids in vitro and DCIS in vivo. Knockdown of MMP9 also nullified the invasion inhibition by everolimus in vitro and in vivo.

CONCLUSIONS

Targeting mTORC1 can inhibit DCIS progression to IDC via MMP9 and may be a potential strategy for DCIS or early-stage IDC therapy.

Prognostic Significance of the Combined Expression of Matrix Metalloproteinase-9, Urokinase Type Plasminogen Activator and its Receptor in Breast Cancer as Measured by Northern Blot Analysis

Using Northern blot analysis we have measured the co-expression of the matrix metalloprotease MMP-9, plasminogen activator urokinase type (uPA) and its receptor (uPAR) mRNAs in 81 biopsies of breast carcinomas with the objective of analyzing the impact of these factors on the overall survival probability of the patients (median follow-up time: 4 years). Individual mRNA levels of either uPA or uPAR showed parallel variations with MMP-9 mRNA, suggesting a coordinate transcription of these markers. When median values were used as cutoff points to discriminate between high and low factor expression, no association was found with patient outcome and MMP-9 or uPA mRNA distribution. However, increased uPAR mRNA levels were associated with poor prognosis (p = 0.01). The combination of MMP-9 and uPAR mRNA measurements has not enhanced prognostic information compared to information supplied by the receptor alone (p = 0.01). The combination of MMP-9 and high levels of uPA mRNA led to a significant association with poor outcome (p = 0.03). Multivariate analysis supported the notion that increased uPAR mRNA production in primary breast cancer may be a predictor of overall survival.

Tumor growth model of ductal carcinoma: from in situ phase to stroma invasion

This paper aims at modeling breast cancer transition from the in situ stage -when the tumor is confined to the duct- to the invasive phase. Such a transition occurs thanks to the degradation of the duct membrane under the action of specific enzymes so-called matrix metalloproteinases (MMPs). The model consists of advection-reaction equations that hold in the duct and in the surrounding tissue, in order to describe the proliferation and the necrosis of the cancer cells in each subdomain. The divergence of the velocity is given by the increase of the cell densities. Darcy law is imposed in order to close the system. The key-point of the modeling lies in the description of the transmission conditions across the duct. Nonlinear Kedem-Katchalsky transmission conditions across the membrane describe the discontinuity of the pressure as a linear function of the flux. These transmission conditions make it possible to describe the transition from the in situ stage to the invasive phase at the macroscopic level. More precisely, the membrane permeability increases with respect to the local concentration of MMPs. The cancer cells are no more confined to the duct and the tumor invades the surrounding tissue. The model is enriched by the description of nutrients concentration, tumor necrosis factors, and MMPs production. The mathematical model is implemented in a 3D C⁺⁺-code, which is based on well-adapted finite difference schemes on Cartesian grid. The membrane interface is described by a level-set, and the transmission conditions are precisely approached at the second order thanks to well-suited sharp stencils. Our continuous approach provides new significant insights in the macroscopic modeling of the breast cancer phase transition, due to the membrane degradation by MMP enzymes.

Therapeutic effects of tyroservatide on metastasis of lung cancer and its mechanism affecting integrin-focal adhesion kinase signal transduction

Tyroservatide (YSV) can inhibit the growth and metastasis of mouse lung cancer significantly. This study investigated the therapeutic effects of tripeptide YSV on metastasis of human lung cancer cells and explored its possible mechanism that affects integrin–focal adhesion kinase (FAK) signal transduction in tumor cells. YSV significantly inhibited the adhesion and the invasion of highly metastatic human lung cancer cell lines 95D, A549, and NCI-H1299. In addition, YSV significantly inhibited phosphorylation of FAK Tyr397 and FAK Tyr576/577 in the 95D, A549, and NCI-H1299 human lung cancer cells in vitro. And the mRNA level and protein expression of FAK in these human lung cancer cells decreased at the same time. YSV also significantly inhibited mRNA and protein levels of integrin β1 and integrin β3 in the 95D, A549, and NCI-H1299 human lung cancer cells. Our research showed that YSV inhibited adhesion and invasion of human lung cancer cells and exhibited therapeutic effects on metastasis of lung cancer.

Cellular prion protein regulates invasion and migration of breast cancer cells through MMP-9 activity

Function of cellular prion protein (PrP(c)) in cancer progression has not been elucidated yet. Ectopic expression of PrP(c) increases the invasion and migration of breast cancer cell line, MCF-7 cells. Overexpressed PrP(c) increases matrix metalloprotease-9 (MMP-9) expression by enhancing association of NF-κB in promoter of MMP-9 gene and ERK signaling in MCF-7 cells. Whereas, silencing of PrP(c) by siRNA suppresses ERK activation and MMP-9 expression resulting the down-regulation of MD-MB231 cell migration and invasion. Overall, these results suggest that PrP(c) contribute the breast cancer invasion and migration via MMP-9.

Imaging Matrix Metalloproteinase Activity Implicated in Breast Cancer Progression

Proteolysis has been cited as an important contributor to cancer initiation and progression. One can take advantage of tumor-associated proteases to selectively deliver imaging agents. Protease-activated imaging systems have been developed using substrates designed for hydrolysis by members of the matrix metalloproteinase (MMP) family. We presently describe approaches by which one can optically image matrix metalloproteinase activity implicated in breast cancer progression, with consideration of selective versus broad protease probes.

Tumour-stromal interactions in acid-mediated invasion: a mathematical model

It is well established that the tumour microenvironment can both promote and suppress tumour growth and invasion, however, most mathematical models of invasion view the normal tissue as inhibiting tumour progression via immune modulation or spatial constraint. In particular, the production of acid by tumour cells and the subsequent creation of a low extracellular pH environment has been explored in several 'acid-mediated tumour invasion' models where the acidic environment facilitates normal cell death and permits tumour invasion. In this paper, we extend the acid-invasion model developed by Gatenby and Gawlinski (1996) to include both the competitive and cooperative interactions between tumour and normal cells, by incorporating the influence of extracellular matrix and protease production at the tumour-stroma interface. Our model predicts an optimal level of tumour acidity which produces both cell death and matrix degradation. Additionally, very aggressive tumours prevent protease production and matrix degradation by excessive normal cell destruction, leading to an acellular (but matrix filled) gap between the tumour and normal tissue, a feature seen in encapsulated tumours. These results suggest, counterintuitively, that increasing tumour acidity may, in some cases, prevent tumour invasion.

Leptin utilizes Jun N-terminal kinases to stimulate the invasion of MCF-7 breast cancer cells

In breast tumors, high levels of leptin have been associated with increased incidence of breast cancer metastasis. Breast cancer metastasis is directly associated with breast cancer cell invasion. However, whether leptin could augment breast cancer cell invasion is not known. Here we showed that leptin increased the invasiveness and the matrix metallo-proteinase-2 (MMP-2) activity of the MCF-7 breast cancer cell line. Leptin stimulated the phosphorylation of extracellular signals regulated kinases, signal transducers and activators of transcription 3 and Jun N-terminal kinases (JNK); however, only inhibition of JNK decreased leptin-mediated activation of MMP-2. Furthermore, inhibition of JNK suppressed leptin-mediated breast cancer cell invasion. Here we report the novel findings that leptin increased invasion of breast cancer cells by activating JNK, resulting in increased MMP-2 activity.

Proteolytic activation of matrix metalloproteinase-9 in skin wound healing is inhibited by alpha-1-antichymotrypsin

An excessive amount of matrix metalloproteinase-9 (MMP-9) has been well documented in inflammatory diseases, including chronic wounds and cancers. Secreted as a zymogen, proMMP-9 can be irreversibly converted to a mature form through cleavage of the N-terminal propeptide domain. Although the converting enzyme for proMMP-9 in human tissues is unknown, we previously found that tumor necrosis factor-alpha (TNF-alpha) promotes activation of proMMP-9 in human skin, and characterized the converting activities as tissue-associated chymotrypsin-like proteinases. On the other hand, the pathophysiologic inhibitor to prevent proMMP-9 maturation also remains elusive. In this regard, we observed the presence of the inhibitory property in burn blister fluid that abrogates the skin extract-mediated activation of proMMP-9. Then we determined that alpha-1-antichymotrypsin (alpha-ACT), an acute-phase factor abundantly present in the blister, effectively inhibited proMMP-9 activation in human and rodent skin. In contrast, the aminophenylmercuric acetate-induced "cysteine switch" and activation of proMMP-9 were not affected by alpha-ACT. TNF-alpha-induced activation of proMMP-9 by the explants of human skin was inhibited by alpha-ACT but not by related alpha-1-antitrypsin. alpha-ACT specifically attenuated maturation of proMMP-9 but not proMMP-2 or proMMP-13. Furthermore, short peptides that mimic the reactive center loop (RCL) of alpha-ACT were sufficient to inhibit the conversion. Mutation analysis demonstrated that a conserved leucine within the RCL was critical for alpha-ACT-exerted inhibition. In chronic wounds, a large amount of mature MMP-9 was associated with fragmentation and inactivation of alpha-ACT. Taken together, these results demonstrate that, to the best of our knowledge, alpha-ACT is a previously unreported pathophysiologic inhibitor that controls proMMP-9 activation in skin tissue.

The clinicopathological and prognostic significance of membrane type 1 matrix metalloproteinase (MT1-MMP) and MMP-9 according to their localization in invasive breast carcinoma

AIMS

To investigate the clinicopathological and prognostic significance of membrane type 1 matrix metalloproteinase (MT1-MMP) and MMP-9 proteins expression in invasive breast carcinoma and their relationship to tumour proliferation and expression of c-erbB2 and peroxisome proliferator-activated receptor (PPAR) gamma.

METHODS

Immunohistochemistry was carried out on 175 paraffin-embedded breast tissue specimens to detect MT1-MMP, MMP-9, oestrogen receptor (ER), progesterone receptor, c-erbB-2, Ki67, topoisomerase IIalpha (topo IIalpha) and PPARgamma protein expression.

RESULTS

Both MT1-MMP and MMP-9 were expressed in the cytoplasm of the malignant cells and the peritumoral stroma. Cytoplasmic MT1-MMP was more often observed in ER+ tumours (P = 0.022), of a lower nuclear grade (P = 0.020) and with reduced expression of Ki67 and topo IIalpha (P = 0.027 and P = 0.006, respectively). Moreover, cytoplasmic MT1-MMP was positively associated with MMP-9 (P = 0.010) and PPARgamma (P < 0.0001). Cytoplasmic MMP-9 was inversely associated with Ki67 (P = 0.034) and topo IIalpha (P = 0.004), whereas its relationship with MT1-MMP (P = 0.034) and PPARgamma (P = 0.024) was found to be positive. Stromal MMP-9 was more often observed in c-erbB2+ tumours (P = 0.043) and had an unfavourable impact on overall and relapse-free survival in both univariate (P = 0.0157 and P = 0.0274, respectively) and multivariate analyses (P = 0.007 and P = 0.024, respectively).

CONCLUSIONS

Cytoplasmic MT1-MMP and MMP-9 seem to be related to well-differentiated tumours, with a low proliferation potential, while stromal MMP-9 is associated with an aggressive tumour phenotype and is recognized as an independent poor prognostic indicator.

Enhancing effect of platelet-derived microvesicles on the invasive potential of breast cancer cells

BACKGROUND

Platelets (PLTs) have been postulated to play a role in cancer progression and metastasis. Recently, it was demonstrated that PLT-derived microvesicles (PMVs) transfer various surface receptors and/or adhesion molecules to target cells and modulate their biological responses. In this work, it was hypothesized that PMVs interact with breast cancer cells, increasing their invasiveness.

STUDY DESIGN AND METHODS

PMVs (isolated from outdated PLT concentrates) were incubated with three human breast cancer cell lines (MDA-MB-231, BT-549, and T47D), and their effects on in vitro invasiveness of these cells (adhesion, expression of matrix metalloproteinases [MMPs], and chemoinvasion), as well as their interactions with stroma, were evaluated.

RESULTS

We found that PMVs 1) transferred PLT-derived integrin CD41 to the surface of breast cancer cells and enhanced their adhesion to endothelial cells; 2) increased CXCR4 expression and chemotaxis toward a stromal-derived factor-1 gradient in invasive MDA-231 and BT-549 cells; 3) increased phosphorylation of the mitogen-activated protein kinase p42/44 and AKT signaling pathways; 4) stimulated the production of MMPs in invasive MDA-231 and BT-549 cells and their chemoinvasion across the reconstituted basement membrane Matrigel; and 5) induced the secretion of MMP-9 by marrow fibroblasts and stimulated the secretion of both MMP-2 and MMP-9 in cocultures of fibroblasts with MDA-MB-231 cells.

CONCLUSION

It was shown than PMVs enhance the in vitro invasive potential of invasive breast cancer cell lines and therefore could mediate the progression of breast cancer. These findings warrant further evaluation of the implications of PLT transfusions in cancer patients.

Effects of Runing Recipe medicated serum on expressions of genes in breast cancer cells

OBJECTIVE

To explore the mechanisms of the effects of Runing Recipe in anti-invasion and anti-recurrence of breast cancer by experimental research in vitro.

METHODS

SD female rats were randomly divided into Runing Recipe-treated group and its decomposed formulas Kidney-Warming Recipe and Liver-Soothing Recipe-treated groups, tamoxifen (TAM) -treated group, cyclophosphamide (CTX) -treated group, and normal control group to make medicated serums. Methods of matrigel basement membrane and real-time reverse transcription polymerase chain reaction were employed to investigate the gene expressions of vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) after MDA-MB-435 cells were treated with the medicated serums.

RESULTS

The gene expression of VEGF was dropped in CTX-treated, TAM-treated and Liver-Smoothing Recipe-treated groups. The gene expression of TIMP-1 was up-regulated in CTX-treated, Runing Recipe-treated and Kidney-Warming Recipe-treated groups; while MMP-9 was down-regulated in these groups.

CONCLUSION

The mechanisms of Runing Recipe in inhibiting the cancer cell invasion may be related to down-regulating the gene expressions of VEGF and MMP-9, and up-regulating the gene expression of TIMP-1.

The activity of matrix metalloproteinases (MMPS) and tissue inhibitors of metalloproteinases (TIMPs) in mammary tumors of dogs and rats

We conducted zymography for detecting the activity of matrix metalloproteinases (MMPs) and reverse zymography for the activity of tissue inhibitors of metalloproteinases (TIMPs) in canine spontaneous and rat 7, 12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumor tissues. The activities of MMPs of canine mammary tumors were quite higher than those of the rat chemically induced tumors. The activities of MMPs were significantly higher in malignant tissues than in benign ones of canine tumors, whereas the activity of only MMP-2 was higher in both benign and malignant rat tumors compared to normal tissues. There were no differences of MMPs activities between benign and malignant rat tumors. The results of reverse zymography indicated that the activities of TIMP-1, -2 and -3 were strikingly higher in rat tumors than in canine tumors. The activities were higher in malignant tissues than in benign ones of dogs, and higher in tumor tissues than in normal mammary tissues of rats. The results of film in situ zymography for tissue localization of gelatinolytic activity showed that the digested area was more extended in malignant tumors than in benign ones of dogs. However, the area was similarly extended in both benign and malignant rat tumors. These results may indicate that the canine spontaneous malignant mammary tumors possess more aggressive nature than the rat chemically induced counterpart, resulting from the high level of MMPs and low level of TIMPs activities of the tumor tissues.

Roles for neuregulins in human cancer

The human epidermal growth factor (EGF) receptor (HER) family of receptor tyrosine kinases has frequently been implicated in cancer. Apart from overexpression or mutation of these receptors, also the aberrant autocrine or paracrine activation of HERs by EGF-like ligands may be important in cancer progression. Neuregulins constitute a family of EGF-like ligands that bind to HER3 or HER4, preferably forming heterodimers with the orphan receptor HER2. Mesenchymal neuregulin typically serves as a pro-survival and pro-differentiation signal for adjacent epithelia. Disruption of the balance between proliferation and differentiation, because of autocrine production by the epithelial cells, increased sensitivity to paracrine signals or disruption of the spatial organization, may lead to constitutive receptor activation, in the absence of receptor overexpression. Consequently, the analysis of ligand expression and/or activated receptors in tumor samples may broaden the group of patients that can benefit from targeted therapies.

Co-stimulation of human breast cancer cells with transforming growth factor-beta and tenascin-C enhances matrix metalloproteinase-9 expression and cancer cell invasion

Transforming growth factor-beta (TGF-beta), tenascin-C (TN-C) and matrix metalloproteinases (MMPs) have been demonstrated independently to be associated with disease progression and poor prognosis in patients with breast cancer. The present study explored effects of TGF-beta and TN-C on MMP-9 expression and cancer invasion. An experimental study was designed to analyse MDA-MB-231 breast cancer cells, known for their high invasiveness, after stimulation with TGF-beta1 and/or TN-C. TGF-beta1 stimulated TN-C expression in the cells. Co-stimulation of MDA-MB-231 cells with TN-C and TGF-beta increased MMP-9 expression at both the gene (28-fold) and the protein levels. The in vitro invasion also increased (4-fold). GM6001 inhibited the invasion induced by the co-stimulation. The combined effect of TN-C and TGF-beta resulted in enhanced MMP-9 expression and cancer invasion in vitro.

Genetic polymorphisms in the MMP-2 and MMP-9 genes and breast cancer phenotype

The matrix metalloproteinases (MMPs) have been shown to play important roles in cancer progression. In this study we examined whether common genetic variants in two key MMPs are associated with phenotypic features of breast cancers and patient outcome. A single nucleotide polymorphism in the promoter region of MMP-2 (-1306 C-->T) abolishes Sp1 binding and is associated with lower transcriptional activity, while another in the promoter region of MMP-9 (-1562 C-->T) increases the transcription of this gene. MMP-2 TT homozygous patients had smaller tumors (p=0.006) and contained lower concentrations of estrogen receptor (ER; p=0.002) compared to patients with the MMP-2 CC or CT genotype. Homozygosity for the MMP-2 -1306 T allele was associated with markedly different patient survival depending upon tumor ER status. For patients with ER negative tumors, the MMP-2 TT genotype was associated with poor survival (2/8 patients alive at end of study, 25%) compared to the CC or CT genotypes (59/70, 84%; p < 0.001). For patients with ER positive tumors, the MMP-2 TT genotype was associated with a trend for very good survival (10/10, 100%) compared to the CC or CT genotypes (130/157, 83%; p=0.16). The MMP-9 -1562 T allele was associated with features of good prognosis including non-ductal type histology, positive ER status and the absence of TP53 mutation. Patients with MMP-9 -1562 CT or TT genotypes showed marginally better prognosis compared to CC homozygotes (p=0.06). These findings suggest that breast cancer phenotype and outcome can be influenced by common functional polymorphisms in MMP genes.

Pro-matrix metalloproteinase-2 transfection increases orthotopic primary growth and experimental metastasis of MDA-MB-231 human breast cancer cells in nude mice

The ability to activate pro-matrix metalloproteinase (pro-MMP)-2 via membrane type-MMP is a hallmark of human breast cancer cell lines that show increased invasiveness, suggesting that MMP-2 contributes to human breast cancer progression. To investigate this, we have stably transfected pro-MMP-2 into the human breast cancer cell line MDA-MB-231, which lacks MMP-2 expression but does express its cell surface activator, membrane type 1-MMP. Multiple clones were derived and shown to produce pro-MMP-2 and to activate it in response to concanavalin A. In vitro analysis showed that the pro-MMP-2-transfected clones exhibited an increased invasive potential in Boyden chamber and Matrigel outgrowth assays, compared with the parental cells or those transfected with vector only. When inoculated into the mammary fat pad of nude mice, each of the MMP-2-tranfected clones grew faster than each of the vector controls tested. After intracardiac inoculation into nude mice, pro-MMP-2-transfected clones showed a significant increase in the incidence of metastasis to brain, liver, bone, and kidney compared with the vector control clones but not lung. Increased tumor burden was seen in the primary site and in lung metastases, and a trend toward increased burden was seen in bone, however, no change was seen in brain, liver, or kidney. This data supports a role for MMP-2 in breast cancer progression, both in the growth of primary tumors and in their spread to distant organs. MMP-2 may be a useful target for breast cancer therapy when refinement of MMP inhibitors provides for MMP-specific agents.

Expression of matrix metalloproteinase-2 and -9 and tissue inhibitor of metalloproteinase-1 and -2 in intraductal and nonintraductal growth type of cholangiocarcinoma

BACKGROUND

The intraductal growth (IG) type of cholangiocarcinoma has a better prognosis than the mass forming (MF) and periductal infiltrating (PI) types. Matrix metalloproteinase (MMP)-2 and MMP-9, regulated by tissue inhibitor of metalloproteinases (TIMP)-2 and TIMP-1, respectively, play important roles in the degradation of the basement membrane during tumor invasion. Alteration in MMPs and TIMPs may regulate the gross morphology of cholangiocarcinoma.

METHODS

MMP-2 and MMP-9 were analyzed in 35 cholangiocarcinomas and 4 normal livers with fresh tissue using zymography and real-time reverse transcription-polymerase chain reaction (RT-PCR), and expressions of MMP-2, MMP-9, TIMP-1, and TIMP-2 were evaluated in 76 cholangiocarcinomas by immunohistochemistry.

RESULTS

Activity of MMP-2 and its active form were detected in 80% and 57% of cholangiocarcinomas respectively. The total MMP-2, active 62 kDa MMP-2, and MMP-2 mRNA increased 5.4 and 8.2 times, 4.4 and 10.9 times, and 2.9 and 5.8 times in the MF and PI types, respectively, compared to the IG type. The majority of MMP-9 was in the proform and active 82 kDa MMP-9 was detected in 9% of cholangiocarcinomas. MMP-9 revealed no significant difference in relation to the gross types. The balanced expressions of MMP-2/TIMP-2 and MMP-9/TIMP-1 were significantly decreased in the MF and PI types, compared to the IG type. In the normal and nonneoplastic livers, the expressions of MMP-2 and MMP-9 were very low without active forms.

CONCLUSIONS

The activities of MMP-2 and loss of balanced expressions of MMP-2/TIMP-2 and MMP-9/TIMP-1 are suggested as playing important roles in invasive growth related to the gross type of cholangiocarcinoma.

Cooperation between monocytes and breast cancer cells promotes factors involved in cancer aggressiveness

In breast cancers, clinical symptoms of inflammation localised around the tumour at the time of diagnosis have been considered to have poor prognosis significance. In this study, the biological mechanisms responsible for the deleterious action of monocytes in cancer were investigated. The incubation of the breast-cancer-derived MDA-MB231 cells with monocytes resulted in an increase in factors involved in cell invasion (i.e. both cancer cells and monocytes-associated urokinase and Tissue Factor, and PAI-1 and MMP-9 secretion). Moreover, the functions of monocytes were also modified. Incubation of monocytes with MDA-MB231 cancer cells resulted in a downregulation in the secretion of the antiproliferative cytokine Oncostatin M, while the apoptotic factor TNF alpha was dramatically increased. However, MDA-MB231 cancer cells have been shown to be resistant towards the apoptotic action of TNF alpha. These findings demonstrate that incubation of MDA-MB231 cancer cells with monocytes induced a crosstalk, which resulted in an increased expression of factors involved in cancer cell invasiveness and in a modification of monocytes function against cancer cells, while inflammatory effects were increased.

Molecular prognostic indicators in breast cancer

Here we review a panel of oncogene products, proteases and markers of proliferation that have shown potential as prognostic indicators in primary breast cancer. The relative merits of specific genetic mutations as well as alterations at the protein level are discussed. Finally an assessment is made of the transfer of knowledge from the laboratory to the bed-side.

Tumor necrosis factor-alpha-induced proteolytic activation of pro-matrix metalloproteinase-9 by human skin is controlled by down-regulating tissue inhibitor of metalloproteinase-1 and mediated by tissue-associated chymotrypsin-like proteinase

The proteolytic activation of pro-matrix metalloproteinase (MMP)-9 by conversion of the 92-kDa precursor into an 82-kDa active form has been observed in chronic wounds, tumor metastasis, and many inflammation-associated diseases, yet the mechanistic pathway to control this process has not been identified. In this report, we show that the massive expression and activation of MMP-9 in skin tissue from patients with chronically unhealed wounds could be reconstituted in vitro with cultured normal human skin by stimulation with transforming growth factor-beta and tumor necrosis factor (TNF)-alpha. We dissected the mechanistic pathway for TNF-alpha induced activation of pro-MMP-9 in human skin. We found that proteolytic activation of pro-MMP-9 was mediated by a tissue-associated chymotrypsin-like proteinase, designated here as pro-MMP-9 activator (pM9A). This unidentified activator specifically converted pro-MMP-9 but not pro-MMP-2, another member of the gelatinase family. The tissue-bound pM9A was steadily expressed and not regulated by TNF-alpha, which indicated that the cytokine-mediated activation of pro-MMP-9 might be regulated at the inhibitor level. Indeed, the skin constantly secreted tissue inhibitor of metalloproteinase-1 at the basal state. TNF-alpha, but not transforming growth factor-beta, down-regulated this inhibitor. The TNF-alpha-mediated activation of pro-MMP-9 was tightly associated with down-regulation of tissue inhibitor of metalloproteinase-1 in a dose-dependent manner. To establish this linkage, we demonstrate that the recombinant tissue inhibitor of metalloproteinase-1 could block the activation of pro-MMP-9 by either the intact skin or skin fractions. Thus, these studies suggest a novel regulation for the proteolytic activation of MMP-9 in human tissue, which is mediated by tissue-bound activator and controlled by down-regulation of a specific inhibitor.

MMP-2 and MMP-9 expression in breast cancer-derived human fibroblasts is differentially regulated by stromal-epithelial interactions

Tissue remodeling is a key element in the local invasion and metastasis of malignant breast tumors. The degradation of extracellular matrix that is associated with this process is thought to be mediated by a number of Zn2+-dependent matrix metalloproteinases (MMPs). In most cases these enzymes are not produced by the malignant epithelium itself but by adjacent breast stroma, suggesting an important role for cell-cell interactions. We have analyzed Gelatinase A (MMP-2) and Gelatinase B (MMP-9) gene expression in a panel of six breast cancer cell lines and six primary cultures of stromal cells deriving from breast cancer biopsies. With one exception we did not detect MMP-2 or MMP-9 gene expression in any of the established tumor cell lines. Conversely, tumor stroma-derived fibroblasts expressed MMP-2 mRNA. although no MMP-9 mRNA was seen in RNase protection assays. When fibroblasts were cultured in the presence of media conditioned by MCF-7 tumor cells, MMP-2 enzyme production increased but MMP-9 activity remained undetectable. However, when fibroblasts and MCF-7 tumor cells were co-cultured together, MMP-9 was induced. These observations were confirmed by immunocytochemical analysis of co-cultures of MCF-7 and tumor-derived fibroblasts in which MMP-2 and MMP-9 protein expression was confined to stromal cells adjacent to MCF-7 tumor cells. No MMP-2 or MMP-9 staining was detected in monocultures of the two respective cell types. We conclude that MMP-2 expression is present in the stroma of malignant tumors and is increased by paracrine stimulation mediated by soluble factors. In contrast, MMP-9 expression tumor-derived fibroblasts requires direct contact with malignant tumor epithelium.

MMP-9 secretion and MMP-2 activation distinguish invasive and metastatic sublines of a mouse mammary carcinoma system showing epithelial-mesenchymal transition traits

We have investigated the gelatinase profiles and invasiveness of clonal tumour sublines derived from a spontaneously arising mammary tumour in a Balb/cfC3H mouse. The 67NR. 66c14 and 4T1.2 sublines have low, intermediate and high metastatic potential respectively. In Boyden chamber studies, Matrigel invasion was seen to be progressively higher in the more metastatic lines 4T1.2>66c14>67NR, consistent with MMP-2 activation potential, MMP-9 secretion, and migration over either type I or IV collagen, which were low in both 67NR and 66c14 cells compared to 4T1.2 cells. These attributes are consistent with those seen in human breast cancer cell lines which appear to have undergone an epithelial-mesenchymal transition (EMT) as indicated by vimentin expression. We were, however, surprised to find vimentin expression, MT1-MMP expression and stellate Matrigel outgrowth in the non-invasive, non-metastatic 67NR cells. indicating that they had undergone an EMT despite not being invasive. We conclude that the EMT is manifested to differing degrees in these three clonal cell lines, and that the 67NR cells have either undergone a partial EMT or have since lost certain important attributes of the EMT-derived phenotype. This model should prove useful in further characterizing the regulation of MTI-MMP mediated MMP-2 activation and delineating the EMT in breast cancer progression.

Matrix metalloproteinase inhibitors: past lessons and future prospects in breast cancer

The matrix metalloproteinases (MMPs) play a central role in invasion and metastasis. However, despite striking activity in preclinical models, the clinical development of the matrix metalloproteinase inhibitors (MMPIs) has been difficult. The results of important phase III trials are now emerging and it is therefore opportune to review the current state of the MMPIs. In this article the evidence for the role of MMPs in the progression of breast cancer, the development of the MMPIs and the recent phase III results are discussed. Despite the problems encountered it is hoped that the MMPIs may yet provide another mechanism for the long-term control of micrometastatic disease. Furthermore, important lessons can be learnt from their development that are relevant to the development of other biological agents.

Transforming growth factor-beta - and tumor necrosis factor-alpha -mediated induction and proteolytic activation of MMP-9 in human skin

Both cytokines and matrix metalloproteinases (MMPs) are active during physiologic and pathologic processes such as cancer metastasis and wound repair. We have systematically studied cytokine-mediated MMP regulation. Cytokine-mediated proteinase induction and activation were initially investigated in organ-cultured human skin followed by determination of underlying cellular and molecular mechanisms using isolated skin cells. In this report we demonstrate that tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) synergistically induce pro-MMP-9 in human skin as well as isolated dermal fibroblasts and epidermal keratinocytes. Furthermore, TNF-alpha promotes proteolytic activation of pro-MMP-9 by conversion of the 92-kDa pro-MMP-9 to the 82-kDa active enzyme. This activation occurred only in skin organ culture and not by either isolated fibroblasts or keratinocyte, although the pro-MMP-9 activation could be measured in a cell-free system derived from TNF-alpha-activated skin. The cytokine-mediated induction of pro-MMP-9 in dermal fibroblasts was evident by increased mRNA. At the transcription level, we examined the cytokine-mediated transactivation of the 5'-region promoter of the human MMP-9 in dermal fibroblasts. The results demonstrated that TNF-alpha and TGF-beta could independently stimulate the 5'-flanking 670-base pair promoter. A TGF-beta-response element (-474) and an NF-kappaB-binding site (-601) were identified to be the cis-elements for TGF-beta or TNF-alpha activation, respectively. Taken together, these findings suggest a specific mechanism whereby multiple cytokines can regulate MMP-9 expression/activation in the cells of human skin. These results imply roles for these cytokines in the regulation of MMP-9 in physiologic and pathologic tissue remodeling.

Overexpression of matrix-metalloproteinase-9 in human breast cancer: a potential favourable indicator in node-negative patients

Matrix metalloprotease-9 (MMP-9; 92 kDa type IV collaganase, gelatinase B) is regarded as, important for degradation of the basement membrane and extracellular matrix during cancer invasion and other tissue-remodelling events. In this study we evaluate the prognostic value of MMP-9, by immunoperoxidase staining in a series of 210 breast cancer tissues. The results were quantitated using the HSCORE system, which consider both staining intensity and the percentage of cells stained at given intensities. MMP-9 status was compared with the concentration of cytosolic Cathepsin-D and with other established prognostic factors, in terms of disease free survival and overall survival. The median follow-up period was 62 months. MMP-9 staining was observed primarily in cancer cells, and to a lesser degree in surrounding stromal cells. MMP-9 expression was not detected in normal breast tissue. Levels of MMP-9 expression below the cut-off point were more frequently observed in larger (P = 0.014), invasive ductal histologic (P = 0.037), progesterone receptor (PR)-negative and PR-strong positive tumours (P< 0.001), as well as samples belonging to patients with stage III-IV disease (P = 0.009) and age 45-55 years (P = 0.011). In univariate analysis, node-negative breast cancer patients with tumors positive for MMP-9 had a considerable reduction in risk for relapse (RR = 0.45;P = 0.039) or death (RR = 0.32;P = 0.009). Multivariate analysis indicated that MMP-9 status was an independent favourable predictor of OS (RR = 0.47;P = 0.034) in node-negative but not in node-positive patients. Our results suggest that MMP-9 may be an independent favourable prognostic factor in node-negative breast cancer patients. The overexpression of MMP-9 in breast cancer may be also used as a marker to subdivide node negative breast cancer patients in order to determine the optimal treatment modality.

Matrix metalloproteinase 9 promoter activity is induced coincident with invasion during tumor progression

Matrix metalloproteinase 9 (MMP-9, also known as gelatinase B or 92-kd Type IV collagenase) is overexpressed in many human and murine cancers. We induced carcinomas in mice carrying a transgene that links the MMP-9 promoter to the reporter ss-galactosidase so that activation of the MMP-9 promoter would be indicated by ss-galactosidase. Mammary carcinomas were induced by mating the MMP-9 promoter reporter transgenic mice with mice carrying a transgene for murine mammary tumor virus promoter linked to polyoma middle T antigen, a transgene that leads to rapid development of mammary tumors in female mice. None of the hyperplastic mammary glands and none of the carcinomas in situ expressed ss-galactosidase. However, all invasive tumors had evidence of ss-galactosidase expression. In addition to the breast carcinomas, a malignant teratoma in a female and a papillary adenocarcinoma in the pelvic region of a male arose and were also ss-galactosidase positive. We also induced skin tumors in the mice with the MMP-9 reporter transgene with 7, 12-dimethylbenz[a]anthracene (DMBA) treatment followed by phorbol 12 myristate 13-acetate (TPA). None of the papillomas or in situ carcinomas showed any ss-galactosidase expression, but expression was seen in invasive carcinoma. Although normal skin epithelial cells did not express ss-galactosidase, we did find staining in a few cells at the duct of the sebaceous gland at the base of the hair follicles. The MMP-9 reporter transgene did not lead to expression in the alveolar macrophages, confirming that additional upstream sequences are required for expression in macrophages. These experiments have revealed that MMP-9 promoter activity is induced coincident with invasion during tumor progression. Furthermore, this indicates that the more proximal upstream elements of the promoter are sufficient for MMP-9 transcription during tumor progression.

Association of latent membrane protein 1 and matrix metalloproteinase 9 with metastasis in nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a highly metastatic carcinoma whose consistent association with Epstein-Barr virus (EBV) has been established. Latent membrane protein 1 (LMP1), an EBV membrane protein expressed in latent infection, is considered to be the EBV oncoprotein. Matrix metalloproteinase 9 (MMP9), one of the MMP families, degrades Type IV collagen, a major component of extracellular matrix and is believed to be crucial for cancer invasion and metastasis. Although MMP9 is reported to be expressed in a variety of cancers, no reports concerning NPC have been published to date to the authors' knowledge. Recently, the authors have shown that LMP1 induces MMP9 in vitro cell line, which suggests the possibility of a mechanism in which LMP1 of EBV contributes to the metastasis and tumorigenesis of NPC by the induction of MMP9.

METHODS

The expressions of LMP1 and MMP9 were immunohistochemically examined in 38 NPC sections, and the relation of these proteins were statistically analyzed. The authors also analyzed the associations of these proteins with clinical features.

RESULTS

Both LMP1 and MMP9 proteins were predominantly immunolocalized in cancer nests. The expression of MMP9 showed a significant positive correlation with the expression of LMP1 (r = 0.75; P < 0.0001). Also, the expression of MMP9 correlated with lymph node metastasis (P = 0. 0004).

CONCLUSIONS

The results suggest that the induction of MMP9 by LMP1 contributes to the metastatic potential of NPC.

Biological mechanisms in breast cancer invasiveness: relevance to preventive interventions

Migration studies suggest that the high incidence of postmenopausal breast cancer in Western women is related mainly to epigenetic factors. Progression from ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) also appears to involve environmental rather than genetic factors, and a role has been postulated for metabolic-endocrine changes related to the Western lifestyle. Protein kinase C (PKC) is important in cell signal transduction, and laboratory studies show that PKC stimulates the activities of urokinase plasminogen activator, matrix metalloproteinases and cell adhesion molecules, all of which are known to increase invasiveness in human mammary cancer cell lines. In rodents, the activity of PKC in tissue cells is enhanced by insulin, and PKC isoenzymes have been shown to stimulate the development of hyperinsulinaemic insulin resistance in rodents. Clinically, hyperinsulinaemia and the concomitant increase in circulating levels of free oestradiol and bioactive insulin-like growth factor 1 (IGF1) are each confirmed markers of high risk for breast cancer in women. Lesions of DCIS show evidence of regression with mammary involution, but it is postulated that this may be opposed by the concomitants of hyperinsulinaemic insulin resistance. The prevalence of the latter is increasing in Western populations, and a combination of high IGF1 and low IGF-binding protein 3 concentrations has been associated with the presence of DCIS lesions in premenopausal women. Measures that enhance insulin sensitivity in such women may reduce the risk of progression in DCIS lesions, and a clinical trial is proposed to test the hypothesis.

Thrombin receptor overexpression in malignant and physiological invasion processes

Although the involvement of soluble and matrix-immobilized proteases in tumor cell invasion and metastasis is well recognized, the role of proteolytically activated cell surface receptors has not been elucidated. We report here that thrombin receptor, a member of the protease-activated receptor family, is preferentially expressed in highly metastatic human breast carcinoma cell lines and breast carcinoma biopsy specimens. Introduction of thrombin receptor antisense cDNA considerably inhibited the invasion of metastatic breast carcinoma cells in culture through a reconstituted basement membrane. During placental implantation of the human embryo, thrombin receptor is transiently expressed in the invading cytotrophoblasts. These results emphasize the involvement of thrombin receptor in cell invasion associated with tumor progression and normal embryonic development.