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At least 631 records · Page 35Linked to original sources
PubMed2005

[Correlations between serum matrix metalloproteinase (MMP-1, MMP-3, MMP-9, MMP-13) concentrations and markers of disease activity in early rheumatoid arthritis].

The purpose of this study was to analyse the correlations between serum concentrations of the matrix metalloproteinases (MMP-1, MMP-3, MMP-9, MMP-13) and clinical markers of disease activity in patients with early rheumatoid arthritis (RA). The study group consisted of 30 RA patients, untreated with disease modifying antirheumatic drugs (DMARDs) or corticosteroids, with disease duration less than 3 years. The analysis of serum concentrations of MMPs was based on a quantitative sandwich ELISA. We observed the positive significant correlations between studied MMPs and clinical markers of disease activity, such as number of swollen joints or erythrocyte sedimentation rate (ESR). Furthermore, we revealed significant correlations between serum MMP-1, MMP-3, MMP-9, MMP-13 concentrations and disease activity score (DAS) (p < 0.01; p < 0.001; p < 0.001; p < 0.05 respectively). We conclude that studied matrix metallo-proteinases might be useful clinical markers of disease activity in early rheumatoid arthritis.

Adult↗
PubMed1997

Immunohistochemical expression of cathepsin D in correlation with extracellular matrix component, steroid receptor status and proliferative indices in breast cancer.

In 87 breast cancer patients, the immunohistochemical expression of the basement membrane (BM)-degrading enzyme cathepsin D (CD) was correlated with the expression of extracellular matrix components, with growth fraction, steroid receptor content and with the other conventional prognostic variables in breast cancer. Only 6.25% of tumours had laminin-defined BM, while 86.8% showed staining for fibronectin. CD was also identified in carcinoma cells (cancer cell CD; CCCD) and in stromal cells (stromal cell CD; SCCD). Forty-five percent of tumours showed CCCD and 47.5%, SCCD expression. CCCD expression was significantly correlated with positive oestrogen receptor content, with low Ki-67 and high PCNA score and with SCCD expression. There was no correlation with collagen type IV, laminin or fibronectin. SCCD expression was positively correlated with collagen type IV, laminin expression and tumour grade. The data suggest that the CD of tumour cells and the CD of tumour-associated macrophages have different roles in breast cancer. CCCD correlates with cell proliferation and is regulated by oestrogens, while SCCD relates to cell differentiation, is oestrogen-independent, and has a proteolytic role in the breakdown of BM components.

Breast Neoplasms↗
PubMed2001

Extracellular matrix gene expression correlates to left ventricular mass index after surgical induction of left ventricular hypertrophy.

The cardiac extracellular matrix (ECM) is a dynamic entity maintaining the structural and functional properties of the myocardium. Little is known about alterations in ECM regulation during controlled induction of compensated left ventricular hypertrophy (LVH) using experimental aortic stenosis. Fifteen growing sheep received supra-coronary banding at an age of 7 +/- 1 months whereas 10 age-matched sheep served as the control group (C). Explantation of the hearts was performed 8.3 +/- 1 months after banding. Gene sequences for sheep matrix metalloproteinase (MMP)-1,-2,-3,-9 and tissue inhibitors (TIMP)-1,-2,-3 were isolated and cloned. Then mRNA and protein gene expression analyses were performed. Concentric LVH with no evidence of heart failure was diagnosed at explantation. Left ventricular mass index (LVMI) was 150 +/- 33 g/m2 (LVH) versus 88 +/- 23 (C) and 82 +/- 21 (baseline) (p < 0.01 versus LVH). Parallel to LVH there was a significant increase in mRNA and protein expression for MMP-1,-2,-3, -9 and for TIMP-1,-2 whereas there was a significant decrease in TIMP-3 gene expression. A close correlation between changes in LVMI and ECM gene expression was found. Compensated LVH goes along with a significant modification of MMP and TIMP gene expression. Alterations in ECM gene expression may be part of the adaptive process during left ventricular remodeling.

Animals↗
PubMed1987

Alterations in the nuclear matrix protein mass correlate with heat-induced inhibition of DNA single-strand-break repair.

The total protein mass co-isolating with the nuclear matrix or nucleoid from Chinese hamster ovary (CHO) cells was observed to increase in heated cells as a function of increasing exposure temperature between 43 degrees C and 45 degrees C or of exposure time at any temperature. The sedimentation distance of the CHO cell nucleoid in sucrose gradients increased with increasing exposure time at 45 degrees C. Both these nuclear alterations correlated in a log-linear manner with heat-induced inhibition of DNA strand break repair. A two-fold threshold increase in nuclear matrix protein mass preceded any substantial inhibition of repair of DNA single-strand breaks. When preheated cells (45 degrees C for 15 min) were incubated at 37 degrees C the nuclear matrix protein mass and nucleoid sedimentation recovered with a half-time of about 5 h, while DNA single-strand-break repair recovered with a half-time of about 2 h. When preheated cells were placed at 41 degrees C (step-down heating; SDH) a further increase was observed in the nuclear matrix protein mass and the half-time of DNA strand break repair, while nucleoid sedimentation recovered toward control values. These results implicate alterations in the protein mass of the nuclear matrix in heat-induced inhibition of repair of DNA single-strand breaks.

Animals↗
PubMedDate not supplied

Immunohistochemical evaluation of cathepsin D expression in colorectal tumours: a correlation with extracellular matrix components, p53, pRb, bcl-2, c-erbB-2, EGFR and proliferation indices.

The immunohistochemical Cathepsin D (CD) expression of tumour and stromal cells was investigated in a series of 93 human colorectal adenocarcinomas and 22 adenomas with the intention to evaluate its prognostic significance and its contribution in the metastatic potential of colorectal cancer. CD expression was correlated with the expression of extracellular matrix components (collagen type IV, laminin and fibronectin), p53 protein, pRb, bcl-2, c-erbB-2, EGFR, proliferation indices (Ki-67, PCNA) as well as with other conventional clinicopathological features. CD expression (> 10% of positive tumour cells) was observed in 60.2% of carcinomas and in 72.7% of adenomas. Stromal CD expression was detected in all cases. A statistically significant positive correlation between neoplastic cells CD and stromal cells CD (SCCD) was observed in both carcinomas and adenomas. Cancer cells CD (CCCD) was positively correlated with collagen type IV and pRb expression as well as with PCNA score. In carcinomas, SCCD expression was statistically correlated with p53 protein and pRb expression and a trend for correlation with PCNA score was found. These data suggest that Cathepsin D of cancer and stromal cells, especially in combination with other markers, may provide more information about the biological behaviour of colorectal cancer.

Adenocarcinoma↗
PubMedDate not supplied

Expression of cathepsin D in urothelial carcinoma of the urinary bladder: an immunohistochemical study including correlations with extracellular matrix components, CD44, p53, Rb, c-erbB-2 and the proliferation indices.

The immunohistochemical Cathepsin D (CD) expression of tumor and stromal cells was investigated in a series of 77 urothelial carcinomas of the urinary bladder with the intention to evaluate its prognostic significance and its contribution to the metastatic potential of bladder cancer. CD expression (clone D13A) was correlated with the expression of extracellular matrix components (collagen type IV, laminin, fibronectin), CD44, p53, pRb, proliferation indices (PCNA and MIB1) as well as with other conventional clininopathological features. CD expression (> 10% of positive tumor cells) was observed in 77.9% of the carcinomas. Stromal CD expression was detected in all cases. Linear collagen type IV and laminin deposit at the tumor-stroma border (in > 25% of the BM) was found in 26% and 57.6% of the cases, respectively. The CD of cancer cells (CCCD) was inversely-correlated with the CD of the stromal cells (p = 0.039), tumor grade (p = 0.0028), tumor stage (p = 0.0046), p53 protein (p = 0.05) and positively-correlated with CD44 (p = 0.002) and pRb (p = 0.05). The stromal cells CD (SCCD) showed a statistically significant positive correlation with tumor grade (p < 0.0001) and stage (p = 0.0001), and the proliferation indices PCNA and MIB1 (p = 0.0001 and p = 0.0002, respectively). These data suggest that both CD of tumor and stromal cells could play important roles in the expansion of urothelial carcinoma of the urinary bladder.

Adult↗
PubMed2003

MR imaging of normal and matrix-depleted cartilage: correlation with biomechanical function and biochemical composition.

PURPOSE: To correlate articular cartilage function, as reflected in biomechanical properties and biochemical composition, with magnetic resonance (MR) imaging parameters of normal articular cartilage and cartilage partially depleted of matrix components. MATERIALS AND METHODS: Normal articular cartilage from 12 porcine patellae was evaluated biomechanically, biochemically, and with MR imaging (with and without gadolinium enhancement). The patellae were then enzymatically treated to deplete the matrix of either collagen or proteoglycan and then reevaluated biomechanically, biochemically, and with MR imaging. Correlations between cartilaginous tissue function and MR imaging parameters were made. Analysis of variance was performed to assess the effect of enzymatic treatment on measured parameters. Linear correlations among the MR imaging, biochemical, and biomechanical parameters were performed to determine the strengths of the relationships. P <.05 indicated statistically significant differences. RESULTS: Biochemical, biomechanical, and MR analyses enabled detection of changes caused by matrix depletion (P <.05). T2 was the most useful MR imaging parameter for distinguishing proteoglycan loss from collagen loss. T2 correlated significantly with both biomechanical modulus (indicative of cartilage stiffness; P <.001, R2 = 0.51) and biochemical proteoglycan content (P <.001, R2 = 0.44). Differentiation between proteoglycan loss and collagen loss in terms of T1 improved with gadolinium enhancement. With gadolinium enhancement, proteoglycan depletion was associated with a greater decrease in T1 than collagen depletion (P <.05). CONCLUSION: An association between biochemical and biomechanical functional status and MR imaging parameters of articular cartilage was demonstrated. Linear correlations existed between modulus and proteoglycan content in terms of T2. Additionally, proteoglycan loss and collagen loss had differing effects on gadolinium-enhanced T1 when it was expressed as the ratio of T1 after gadolinium enhancement/T1 before gadolinium enhancement.

Analysis of Variance↗
PubMed2003

Expression of vascular endothelial growth factor and matrix metalloproteinase-2 correlates with the invasion and metastasis of hepatocellular carcinoma.

To investigate the relationship of the expression of vascular endothelial factor (VEGF) and matrix metalloproteinase-2 (MMP-2) with the recurrence and metastasis of hepatocellular carcinoma (HCC), the expression of VEGF and MMP-2 in HCC tissue(n = 50) and in normal liver tissue(n = 30) were examined by immunochemistry. The results showed that the positive rates of VEGF and MMP-2 in HCC tissue were 86% and 60% respectively, and in normal liver tissue were 53.3% and 30% respectively. The positive rates of VEGF and MMP-2 in HCC were significantly higher than those in normal liver tissue. The positive rates of VEGF and MMP-2 in HCC with intra- or extra-hepatic metastasis were higher than those of HCC without metastasis. VEGF and MMP-2 play important roles in the invasion and metastasis of HCC.

Adult↗
PubMed2006

Low serum level of pro-matrix metalloproteinase 2 correlates with aggressive behavior in breast carcinoma.

Malignant tumors that are capable of invading surrounding structures and metastasizing possess certain capacities to cross tissue barriers. Matrix metalloproteinases (MMPs), especially gelatinases and their inhibitor molecules, are known to affect the extracellular matrix turnover, and the proteolytic imbalance due to the abnormal expression of these enzymes eventually leads to cancer progression. This has been well documented at the tissue level. In this study, the different forms of the circulating MMP-2 have been studied in the preoperative sera of 71 patients with breast carcinoma. A quantitative enzyme-linked immunosorbent assay was performed for total proMMP-2, proMMP-2-tissue inhibitor of metalloproteinase 2 (TIMP-2) complex, and free active MMP-2. It is shown here, for the first time, that the total proMMP-2 levels in the serum correlate inversely with node positivity, high stage of the disease, and high nuclear grade of the breast tumor. An association with the levels of lower free active MMP-2 and tumor recurrence is also demonstrated. Interestingly, the tumor tissue expression of MMP-2 had an inverse correlation with proMMP-2-TIMP-2 complex levels in the serum. In conclusion, the levels of the total proMMP-2 correlate inversely with tumor burden, whereas free active MMP-2 might be associated with survival. This could indicate that the prognostic value of the circulating forms of MMP-2 is not congruent with the prognostic information obtained from tissue expression. This is further supported by the inverse correlation of the proMMP-2-TIMP-2 complex and MMP-2 tissue expression in the tumor. Therefore, the different forms of circulating metalloproteinases need to be evaluated further to explore their full potential for clinical use.

Adenocarcinoma↗
PubMed2003

Lung matrix metalloproteinase-9 correlates with cigarette smoking and obstruction of airflow.

Cigarette smoking is the most important risk factor for obstruction of airflow in chronic obstructive pulmonary disease (COPD). Matrix metalloproteinases (MMPs) or an imbalance between MMPs and their inhibitors, the tissue inhibitors of MMP (TIMPs), is considered to play a role in the pathogenesis of COPD. We investigated whether the MMPs expression or the imbalance between MMPs and TIMP-1 is associated with the amount of cigarette smoking and the FEV1 value, in the lung parenchyma of 26 subjects (6 non-smokers and 20 cigarette smokers). First, we performed zymographic analysis to identify the profile of the MMPs, which revealed gelatinolytic bands mainly equivalent to MMP-9 in the smokers. We then measured, using enzyme immunoassay, the concentrations of MMP-9 and its inhibitor, TIMP-1. Correlation analysis revealed that both the MMP-9 concentrations and the molar ratios of MMP-9 to TIMP-1 (MMP-9/TIMP-1) were correlated with the amount of cigarette smoking. Furthermore, MMP-9 concentrations were inversely correlated with FEV1. In conclusion, this study shows that MMP-9 expression in human lung parenchyma is associated with cigarette smoking and also with the obstruction of airflow, suggesting that MMP-9 may play a role in the pathogenesis of the cigarette smoke-induced obstruction of airflow known as the characteristic of COPD.

Adult↗
PubMed1991

Invasion of reconstituted basement membrane matrix is not correlated to the malignant metastatic cell phenotype.

Interactions between tumor cells and basement membranes represent a critical step in the progression of neoplasia and in the metastatic process. Reconstituted basement membrane matrix, matrigel, has been recently used with the aim of developing an in vitro assay of tumor cell invasiveness. We have extended these studies by comparing the invasiveness of a large series of normal and malignant epithelial and mesenchymal cells of human and animal origin cultured on matrigel. Normal cells (fibroblasts, glomerular mesangial cells, keratinocytes), human fibrosarcoma cells (HT1080), and reticular sarcoma cells (M5076) clearly established invasive capabilities in the matrix. However, all the other tested cell lines, malignant or virally transformed cells invasive in vivo (MCF7, T47D, SA52, SW613, MO4, A431, BeWo), as well as normal nontransformed cells (MOH22) were incapable of penetration. The morphological features of matrigel invasion by normal fibroblasts and HT1080 cells are described at the light and electron microscope levels. The extent of degradation of a radiolabeled matrigel is minimal and similar in several cell lines reported to be noninvasive or invasive in vivo. Our data suggest that matrigel does not provide a universal model to correlate the invasiveness of cells in vivo and in vitro.

Animals↗
PubMed1999

Matrix metalloproteinases in human melanoma cell lines and xenografts: increased expression of activated matrix metalloproteinase-2 (MMP-2) correlates with melanoma progression.

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are involved in tumour progression and metastasis. In this study, we investigated the in vitro and in vivo expression patterns of MMP-1, MMP-2, MMP-3, MMP-9, TIMP-1 and TIMP-2 mRNA and protein in a previously described human melanoma xenograft model. This model consists of eight human melanoma cell lines with different metastatic behaviour after subcutaneous (s.c.) injection into nude mice. MMP-1 mRNA was detectable in all cell lines by reverse transcription polymerase chain reaction (RT-PCR), but the expression was too low to be detected by Northern blot analysis. No MMP-1 protein could be found using Western blotting. MMP-2 mRNA and protein were present in all cell lines, with the highest expression of both latent and active MMP-2 in the highest metastatic cell lines MV3 and BLM. MMP-3 mRNA was expressed in MV3 and BLM, and in the non-metastatic cell line 530, whereas MMP-3 protein was detectable only in MV3 and BLM. None of the melanoma cell lines expressed MMP-9. TIMP-1 and TIMP-2 mRNA and protein, finally, were present in all cell lines. A correlation between TIMP expression level and metastatic capacity of cell lines, however, was lacking. MMP and TIMP mRNA and protein expression levels were also studied in s.c. xenograft lesions derived from a selection of these cell lines. RT-PCR analysis revealed that MMP-1 mRNA was present in MV3 and BLM xenografts, and to a lesser extent in 530. Positive staining for MMP-1 protein was found in xenograft lesions derived from both low and high metastatic cell lines, indicating an in vivo up-regulation of MMP-1. MMP-2 mRNA was detectable only in xenografts derived from the highly metastatic cell lines 1F6m, MV3 and BLM. In agreement with the in vitro results, the highest levels of both latent and activated MMP-2 protein were observed in MV3 and BLM xenografts. With the exception of MMP-9 mRNA expression in 530 xenografts, MMP-3, MMP-9, and TIMP-1 mRNA and protein were not detectable in any xenograft, indicating a down-regulated expression of MMP-3 and TIMP-1 in vivo. TIMP-2 mRNA and protein were present in all xenografts; interestingly, the strongest immunoreactivity of tumour cells was found at the border of necrotic areas. Our study demonstrates that of all tested components of the matrix metalloproteinase system, only expression of activated MMP-2 correlates with increased malignancy in our melanoma xenograft model, corroborating an important role of MMP-2 in human melanoma invasion and metastasis.

Animals↗
PubMed2000

Expression and activation of matrix metalloproteinase-2 (MMP-2) and its co-localization with membrane-type 1 matrix metalloproteinase (MT1-MMP) correlate with melanoma progression.

Matrix metalloproteinases (MMPs) and their specific tissue inhibitors (TIMPs) play an important role in cancer cell invasion and metastasis. Recently, it was shown that the presence of activated MMP-2 correlates with melanoma progression in vitro. This activation involves coordinated expression of MMP-2, membrane-type 1 MMP (MT1-MMP), and TIMP-2. To investigate the expression profile of these enzymes in human melanoma, this study used tumour specimens obtained from both a human melanoma xenograft model, consisting of eight melanoma cell lines with different metastatic capacity in nude mice, and 60 fresh human cutaneous melanocytic lesions comprising all stages of melanocytic tumour progression. MT1-MMP and TIMP-2 mRNA and protein were present in all cell lines. Cell surface expression level of MT1-MMP, as determined by flow cytometry, was similar on all cell lines. In addition, western blot analysis revealed that both inactive and active MT1-MMP protein was expressed by all cell lines. MMP-2 mRNA and the pro-enzyme form of MMP-2 were expressed by all cell lines. Remarkably, the presence of functionally active MMP-2 was restricted to the most aggressive cell lines MV3 and BLM. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of RNA isolated from subcutaneous xenografts revealed MT1-MMP and TIMP-2 mRNA expression in all lesions, whereas MMP-2 mRNA could be detected only in xenografts derived from the highly metastatic cell lines 1F6m, MV3, and BLM. Furthermore, immunohistochemistry demonstrated a marked increase of MMP-2 and MT1-MMP in MV3 and BLM xenografts, whereas TIMP-2 expression showed no evident correlation with metastatic capacity. In human cutaneous melanocytic lesions, MMP-2, MT1-MMP, and TIMP-2 mRNA were detectable by RT-PCR in all lesions. Expression of MMP-2 protein was not detectable, either in common and atypical naevi, or in melanoma in situ by immunohistochemistry. In these lesions, heterogeneous expression of MT1-MMP and TIMP-2 was present in melanocytic cells. In contrast, a large number of MMP-2 and MT1-MMP-positive tumour cells were observed in primary melanomas and melanoma metastases. Double staining experiments and immunohistochemistry on serial sections from the same lesions demonstrated that all tumour cells expressing MMP-2 also expressed MT1-MMP and TIMP-2. Finally, zymography of melanoma metastases revealed that MMP-2 was present in its functionally active form. This study demonstrates that expression of MT1-MMP and TIMP-2 and activation of MMP-2 are correlated with tumour progression both in the xenograft model and in human melanocytic lesions, strongly suggesting that these factors are required for melanoma invasion and metastasis formation.

Animals↗
PubMed2001

The "early' CD4+CD8+ stage of thymocte differentiation hallmarks the end of a strong positive correlation between extracellular matrix receptor expression and protein tyrosine phosphorylation.

We used irradiation-induced thymic regression/reconstitution to study phosphotyrosine (PTyr) levels and expression of extracellular matrix receptors in thymocyte subsets by flow cytometry. High PTyr levels (PTyr(hi)) characterized cells from the CD4-CD8-(DN)CD25in/hi to the "early" CD4-CD8+(DP)CD25- stage. Correlation indexes (R) between the percentages of these PTyrhi cells and cells with up-regulated expression of alpha4 integrin (alpha4hi) were strongly positive (R= 0.91, P= 0.002, for DN; R= 0.98, P= 0.0001 for DP). At the "early" DP stage, R between PTyrhi cells and cells with up-regulated expression of alpha5 integrin and L-selectin (alpha5hi and L-sel(hi)) also rendered strongly positive (R>0.95, p<0.0003). "Late" expanding DP cells exhibited intermediate PTyr levels (PTyr(in)), associated with a down-regulation of the adhesion receptors assessed. Triple-labeling suggested that in most early CD3-/lo cells, alpha4hi and alpha5hi, but not L-sel(hi) expression preceded a PTyr(hi) content. CD3in/hi-enriched CD8+ cells were also PTyr(hi), but conversely to the immature ones exhibited a tendency for a negative R between PTyr(hi) and alpha4hi (R = -0.93, P = 0.067, n= 4) or alpha5hi cells (R = -0.77, P = 0.23, n = 4). CD4+ cells were either PTyr(hi) or PTyr(in), exhibiting a tendency for a positive R (R = 0.59, P = 0.124, n= 8) between PTyr(hi) and L-sel(hi) cells only. In conclusion, our results associate an up-regulation of alpha4 and alpha5 chains expression with PTyr(hi) levels and, as elsewhere published, with increased adhesion to fibronectin up to the "early" DP stage, but not afterwards.

Animals↗
PubMedDate not supplied

In vivo/in vitro correlations of nitrofurantoin matrix tablet formulations.

In our recent study, a new sustained release dosage form of nitrofurantoin (nft) as matrix tablets by 2(2) factorial design has been prepared by using different drug:polymer ratios. The effect of the polyvinylpyrolidone contents of nft matrix tablets on dissolution rate and bioavailability of the drug have been evaluated. The ideal formulation which fitted at USP XXII dissolution norms was tested by in vivo experiments. The satisfactory correlation was also obtained between the in vivo and the in vitro results. This study suggested that the amounts of nft excreted in urine can be calculated by using in vitro dissolution results and sampling time.

Adult↗
PubMed2003

Matrix metalloproteinase activity correlates with blastema formation in the regenerating MRL mouse ear hole model.

The MRL mouse was proposed as a model of mammalian regeneration because it can close ear holes completely with the restoration of normal tissue. This regeneration process involves the formation of a blastema during healing, the re-appearance of cartilage and hair follicles, and healing without scarring. Such a process requires extensive tissue remodeling. To characterize differences in ear wounding responses between regenerating and nonregenerating mice, we examined and compared the extracellular matrix remodeling and the matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) response in the MRL and C57BL/6 mouse strains after injury. We found a correlation between the MRL's ability to break down the basement membrane, form a blastema, and close ear hole wounds and an inflammatory response with neutrophils and macrophages seen in the ear after injury. These cells were positive for MMP-2 and MMP-9 as well as TIMP-2 and TIMP-3. Clear differences between the MRL and B6 response to injury were seen that could explain the differences in healing and blastema formation in the MRL and lack of it in the B6 mice. This finding was further supported by enzyme activity as determined by gelatin zymography.

Animals↗
PubMed2004

ADAM 12 cleaves extracellular matrix proteins and correlates with cancer status and stage.

ADAM 12 is a member of a family of disintegrin-containing metalloproteases that have been implicated in a variety of diseases including Alzheimer's disease, arthritis, and cancer. We purified ADAM 12 from the urine of breast cancer patients via Q-Sepharose anion exchange and gelatin-Sepharose affinity chromatography followed by protein identification by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Four peptides were identified that spanned the amino acid sequence of ADAM 12. Immunoblot analysis using ADAM 12-specific antibodies detected an approximately 68-kDa band identified as the mature form of ADAM 12. To characterize catalytic properties of ADAM 12, full-length ADAM 12-S was expressed in COS-7 cells and purified. Substrate specificity studies demonstrated that ADAM 12-S degrades gelatin, type IV collagen, and fibronectin but not type I collagen or casein. Gelatinase activity of ADAM 12 was completely abrogated by zinc chelators 1,10-phenanthroline and EDTA and was partially inhibited by the hydroxamate inhibitor Marimastat. Endogenous matrix metalloprotease inhibitor TIMP-3 inhibited activity. To validate our initial identification of this enzyme in human urine, 117 urine samples from breast cancer patients and controls were analyzed by immunoblot. The majority of samples from cancer patients were positive for ADAM 12 (67 of 71, sensitivity 0.94) compared with urine from controls in which ADAM 12 was detected with significantly lower frequency. Densitometric analyses of immunoblots demonstrated that ADAM 12 protein levels were higher in urine from breast cancer patients than in control urine. In addition, median levels of ADAM 12 in urine significantly increased with disease progression. These data demonstrate for the first time that ADAM 12 is a gelatinase, that it can be detected in breast cancer patient urine, and that increased urinary levels of this protein correlate with breast cancer progression. They further support the possibility that detection of urinary ADAM 12 may prove useful in the development of noninvasive diagnostic and prognostic tests for breast and perhaps other cancers.

ADAM Proteins↗