Molecular Human Reproduction, Vol. 7, No. 3, 271-277,
March 2001
© 2001 European Society of Human Reproduction and Embryology
Uterine physiology |
Membrane-type 1 matrix metalloproteinase is induced in decidual stroma without direct invasion by trophoblasts
1 Department of Obstetrics and Gynecology, Hiroshima University School of Medicine, 1-2-3, Kasumi, Minami-ku, Hiroshima 734-8551, and 2 Yoshizato MorphoMatrix Project, ETARO, JST and Developmental Biology Laboratory, Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8526, Japan
Abstract
Membrane-type 1 matrix metalloproteinase (MT1-MMP) in endometrium and decidua may greatly affect attachment of the embryo to the epithelium, invasion of the trophoblast into the stroma, and extracellular matrix remodelling in the endometrium and decidua. We investigated the expression of this enzyme in normally cycling endometrium and in decidua associated with normal and tubal pregnancies at both the gene and protein level. Localization of expression (but not the overall level of expression), differed between endometrium and decidua parietalis and tubal pregnancy decidua. MT1-MMP mRNA was expressed mainly in epithelium and only faintly in stroma throughout the menstrual cycle, while in decidua parietalis and tubal pregnancy decidua, this mRNA was expressed predominantly in stromal cells. MT1-MMP protein was detected in the epithelium alone throughout the menstrual cycle, while in decidua parietalis and tubal pregnancy decidua, it was detected in stromal cells as well as the epithelium. Since decidua showed altered expression in the absence of trophoblastic contact, trophoblast invasion may not directly affect MT1-MMP gene expression.
decidua/endometrium/matrix metalloproteinases/MT1-MMP/stromal cells
Introduction
Embryonic implantation, wound healing, and tumour invasion are processes requiring modification of the microenvironment of the extracellular matrix (ECM) (Hulboy et al., 1997
; Werb et al., 1999). Several types of proteinases including serine proteinases, cysteine proteinases, asparatic proteinases, and metalloproteinases participate in this degradative process. To date, 18 matrix metalloproteinases (MMPs), a multigene family of metal ion-requiring enzymes, have been characterized and classified into five broad categories based on their domain structure, including a group of four recently identified membrane-type metalloproteinases (MT-MMPs) (Seiki, 1999). MT-MMPs are generally made up of six domains including a transmembrane (TM) domain and short cytoplasmic tail at the C-terminus (Sato et al., 1994; Cao et al., 1995; Seiki, 1999). The TM domain provides membrane linkage and is required for activation of proMMP-2 at the cell surface (Sato et al., 1994; Cao et al., 1995; Tokuraku et al., 1995). MT-MMPs also have a furin motif at the cleavage site involved in generation of mature enzymes (Nagase, 1997; Polette and Birembaut, 1998; Seiki, 1999). Activation of proMMP-2 is thought to be associated with ECM remodelling, especially basement membrane remodelling, that occurs in healing of injured tissues as well as during invasion by malignant cells and trophoblast cells.
MT1-MMP was identified and isolated from lung adenocarcinoma cells (Sato et al., 1994). MT1-MMP has a molecular weight of 63 kDa and is made up of 583 amino acid residues. So far, the expression of MT1-MMP mRNA has been demonstrated in many types of malignant tissues and also in non-malignant tissues, e.g. proliferating mesangial cells (Hayashi et al., 1998), stretched cardiac fibroblasts (Tyagi et al., 1998), the cells of granulation tissue during wound healing (Madlener et al., 1998), and osteoclasts carrying out bone resorption (Pap et al., 1999). MT1-MMP mRNA has also been detected in placental tissues (Nawrocki et al., 1996; Bjorn et al., 1997) and fetal membranes (Fortunato et al., 1998). While cells of the decidua basalis are reported to express MT1-MMP mRNA and protein (Nawrocki et al., 1996), it has not been determined whether the changes in its expression in decidua require direct contact between trophoblastic and endometrial cells or whether a different mechanism is involved. We addressed this question using a quantitative reverse transcription–polymerase chain reaction (RT–PCR), in-situ hybridization and immunohistochemistry in endometrium and in decidua associated with normal and tubal pregnancies.
Materials and methods
Specimens
Human endometrial tissues were obtained from hysterectomy specimens from non-pregnant patients aged 43–48 years. The hysterectomies had been performed to treat leiomyoma or adenomyosis. Only histologically normal endometrium was included in the study. Endometrial samples were dated with respect to the menstrual cycle using histological criteria (Noyes et al., 1950); these were proliferative in 10 cases, early secretory (days 14–21) in four cases, and late secretory (days 22 or later) in four cases. With written consent, decidual samples were obtained from three women undergoing voluntary termination at 7–10 weeks gestation. In all cases, a fetal heartbeat was detected by transvaginal ultrasonography. With transabdominal ultrasonographic guidance, the samples were obtained from the decidua parietalis, which is located opposite from the placenta and has no contact with trophoblastic tissue. The absence of trophoblastic tissue was confirmed by immunostaining for cytokeratin. Decidual tissue from three tubal ectopic pregnancies was also studied. Again, immunostaining ruled out the presence of trophoblast. Samples to be studied by quantitative RT–PCR were frozen immediately in liquid nitrogen. When the volume of tissue samples was sufficient, a portion (n = 12; three each from proliferative endometrium, late secretory endometrium, normal decidua parietaris, and decidua from tubal pregnancy) was fixed in 4% paraformaldehyde for in-situ hybridization and immunohistochemistry. Use of the specimens was approved by the institutional review committees at Hiroshima University Hospital, Hiroshima Memorial Hospital, and Hiroshima Prefectual Hospital, Japan.
Quantitative RT–PCR
RNA preparation and cDNA synthesis
Frozen endometrial tissues were homogenized, and total RNA was isolated by the acid guanidinium thiocyanate–phenol–chloroform method (Chomczynski and Sacchi, 1987). RNA concentration was measured spectrophotometically in all samples. Complementary DNA (cDNA) was prepared by reverse transcription at 42°C for 60 min in 20 µl of reaction mixture containing 5 µg of total RNA, 0.5 µg of oligo (dT), and 200 IU of Moloney murine leukaemia virus (MMLV) reverse transcriptase (Life Technologies, Rockville, MD, USA) in 50 mmol/l Tris–HCl (pH 8.3), 40 mmol/l KCl, 6 mmol/l MgCl2, 1 mmol/l dithiothreitol (DTT), and 1 mmol/l each of dATP, dGTP, dCTP, and dTTP.. Transcription reactions were terminated by heating the samples at 70°C for 10 min.
Primers
Primers designed according to known nucleotide sequences were: MT1-MMP, 5' primer: 5'-ATC AAC ACT GCC TAC GAG AG-3' and 3' primer: 5'-AAG ACT TCA TCG CTG CCC AT-3' (nucleotides 1220–1540); and glyceraldehyde 3-phosphate dehydrogenase (G3PDH), 5' primer: 5'-TGA AGG TCG GAG TCA ACG GAT TTG GT-3' and 3' primer: 5'-CAT GTG GGC CAT GAG GTC CAC CAC-3' (nucleotides 71–1053).
PCR
The G3PDH sequence was used as an internal control, since it is ubiquitously expressed in most tissues. In initial experiments, the appropriate amount of template to obtain the exponential range of amplification for the G3PDH gene, was determined by sequential two-fold dilutions of solution containing 1 µl cDNA in sterile distilled water, resulting in dilutions ranging from 1:32 to 1:864. According to these initial results, the PCR reaction was performed in a total volume of 25 µl containing an aqueous 1:96 dilution of cDNA (equivalent to cDNA of 52.0 ng from RNA) in 2.5 µl of 10x PCR buffer (500 mmol/l KCl, 400 mmol/l Tris–HCl, pH 8.3 at 37°C, 25 mmol/l MgCl2, and 100 µg/ml bovine serum albumin), 0.1 mmol/l each of dATP, dGTP, dCTP, and dTTP, 10 pmol each of 5' and 3' primers, and 1 IU of Taq polymerase (Perkin-Elmer Cetus; Fostor City, CA, USA). The amplification profile involved preincubation at 94°C for 5 min, then denaturation at 94°C for 30 s, primer annealing at 60°C for 30 s, and extension at 72°C for 1 min, for 24–32 cycles and, after the last cycle, all samples were incubated for an additional 10 min at 72°C.
Quantification
PCR products were electrophoresed in 0.5x Tris-borate electrophoresis buffer on a 1.2% agarose gel. Intensity of ethidium bromide luminescence was measured using a charge coupled device (CCD) image analyzer (Densitograph AE-6900-F; Atto, Tokyo, Japan).
Subcloning and sequencing of MMP cDNA
MT1-MMP and G3PDH cDNA fragments amplified by PCR were isolated from agarose gels, purified with a Gene Clean II (Funakoshi, Tokyo, Japan), and ligated into pBluescript SK(–) (Stratagene, La Jolla, CA, USA). Competent cells were transformed by introducing the ligated plasmid DNA with heat shock. The transformed bacteria were cultured overnight. By blue–white selection and a colony PCR method, transformed bacteria were selected and grown in liquid culture overnight. The ligated plasmid DNA was purified and its DNA sequences were validated with a Taq Dye Deoxy Terminator Cycle Sequencing Kit (Applied Biosystems, Foster City, CA, USA).
In-situ hybridization
Specimens
Tissue samples were fixed immediately in 4% paraformaldehyde for 24 h. Sections (5 µm) were mounted on 3-aminopropyl-triethoxy silane-coated slides (Matsunami, Osaka, Japan).
cRNA probe preparation
cRNA probes for in-situ hybridization were prepared from MT1-MMP cDNA fragments generated by RT–PCR from human endometrial RNA and subcloned into Bluescript vectors (Stratagene). The plasmid containing MT1-MMP cDNA was linearized by BamHI and ClaI at a site suitable for transcription of cDNA. Linearized plasmids were used to construct probes using fluorecein-labelled uridine triphosphate by in-vitro transcription with T3 and T7 RNA polymerase. The RNA probes were quantified by a spotting method by comparison with known amounts of fluorecein-labelled DNA.
Pretreatment of specimens
Tissue sections were deparaffinized with xylene, rehydrated in decreasing concentrations of ethanol, and rinsed in phosphate-buffered saline (PBS) containing 10% Tween-20 (PBST). The slides were fixed in 4% paraformaldehyde in PBS for 15 min and treated with proteinase K (1 µg/ml) at 37°C for 10 min, following by rinsing in PBS. The specimens were then incubated with chondroitin ABC lyase (0.02 IU/ml) in a buffer solution of 0.1 mol/l Tris–HCl (pH 8.0), 0.03 mol/l sodium acetate, and 0.05% bovine serum albumin at 37°C for 30 min. After rinsing in PBST, sections were refixed in 4% paraformaldehyde/PBS for 10 min and rinsed twice for 10 min in PBST.
In-situ hybridization
Sections were covered with antisense and sense RNA probes in hybridization buffer [50% deionized formamide; 5x standard saline citrate (SSC) at pH 4.5 treated with diethylpirocarbonate; 50 µg/ml yeast tRNA; 1% sodium dodecyl sulphate (SDS); and 50 µg/ml heparin] and incubated at 55°C for 18 h in a humid chamber in the presence of 50% formamide. The cRNA probes were used at concentrations of about 500 ng/ml. After hybridization, sections were washed twice for 30 min with a mixture of 50% formamide, 5x SSC, and 1% SDS at 55°C. Sections were then washed twice for 30 min with a mixture of 50% formamide and 2x SSC at 55°C, followed by incubation in a mixture of 10 mmol/l Tris–HCl (pH 8.0) and 500 mmol/l NaCl with 10 mg/ml RNase A for 30 min at 37°C. Sections were incubated with 0.5% of blocking reagent (Nucleic Acid Detection Kit; Boehringer Mannheim, Germany) in PBST for 1 h at room temperature and then were covered with alkaline phosphatase-conjugated anti-fluorescein antibody (dilution 1:2000) and 0.5% blocking reagent in PBST and allowed to react overnight at 4°C. After rinsing three times for 20 min with PBST including 2 mol/l levamisole, sections were incubated in alkaline phosphatase buffer (0.1 mol/l NaCl, 0.05 mol/l MgCl2, 0.1 mol/l Tris–HCl, pH 9.5, 0.1% Tween-20, 2 mmol/l levamisole) for 5 min at room temperature. The colour reaction was developed with Nitroblue Tetrazolium-4-romo-3-chloro-indolyl phosphate (NBT-BCIP) in alkaline phosphatase reaction buffer in darkness overnight. Sections then were rinsed twice for 15 min with 1x TE (0.01 mol/l Tris–HCl; pH 8.0, 0.01 mol/l EDTA; pH 8.0) at room temperature, fixed in 4% paraformaldehyde in PBS for 30 min, and finally washed twice for 10 min in 1x TE. Sections were not counterstained.
Immunohistochemistry
Formalin-fixed, paraffin-embedded sections were deparaffinized in xylene and rehydrated by routine methods. Sections then were heated to 90°C in a microwave oven in 10 mmol/l citrate buffer for 18 min, followed by cooling in the buffer for 20 min at room temperature. Sections then were incubated in methanol with 0.3% H2O2 for 10 min at room temperature to block endogenous peroxidase activity. Immunohistochemical staining was performed using a Vectastain Elite ABC kit (Vector Laboratories, Burlingame, CA, USA). After blocking non-specific reactivity with diluted normal horse serum, sections were incubated with 10 µg/ml purified mouse anti-human MT1-MMP monoclonal antibody (Fuji Chemical, Toyama City, Japan) for 18 h at 4°C or prediluted purified mouse anti-cytokeratin monoclonal antibody (Nichirei, Tokyo, Japan) for 1 h at room temperature. Next, sections were exposed to biotinylated anti-mouse immunoglobulin G (IgG; Vector Laboratories) for 30 min at room temperature, followed by incubation with avidin–biotin complex (ABC) reagent (Vector Laboratories) for 30 min at room temperature. These reactions were carried out in a humid chamber. Reaction products were visualized using 3-amino-9-ethylcarbazole in the presence of 0.003% H2O2, and sections were counterstained with haematoxylin before clearing and mounting. Negative control sections were processed by substituting non-immune serum for the primary antibody.
Epithelial and trophoblastic cells were identified by cytokeratin immunostaining. Decidualized stromal cells in normal and tubal pregnancy decidua were identified as relatively large, round, cytokeratin-negative cells.
Statistical analysis
Data were analysed by Wilcoxon's test (non-paired). P < 0.05 was considered to be statistically significant.
Results
Quantification of MT1-MMP gene expression by RT–PCR
To quantitatively analyse the level of MT1-MMP mRNA, RT-PCR was performed for 24–32 cycles. PCR products increased exponentially with each cycle until they reached a plateau according to the electrophoretic pattern (Figure 1). G3PDH-specific PCR products increased similarly in all samples (Figure 1). The intensity of ethidium bromide luminescence for MT1-MMP- and G3PDH-specific PCR products was measured using a CCD image analyser and plotted semilogarithmically (Figure 2), with the vertical axis indicating densitometric units corresponding to staining intensity of PCR products and the horizontal axis indicating number of PCR cycles (Figure 2). Linearity of the amplification patterns of MT1-MMP and G3PDH gene PCR products was observed from 24 to 26 cycles. The PCR product was quantified at 26 cycles in the exponential range of amplification. Expression levels of MT1-MMP in secretory endometrium, decidua parietalis, and tubal pregnancy decidua did not differ significantly from those in proliferative endometrium (P > 0.05; Figure 3).
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= proliferative phase endometrium; • = early secretory endometrium; 
= late secretory endometrium; 
= pregnancy decidua; 
= tubal pregnancy decidua.
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In-situ hybridization
Throughout the menstrual cycle, antisense probes disclosed that MT1-MMP mRNA was expressed mainly in the epithelium and was not observed in stromal cells (Figure 4A
and C). Neither sense probes nor sections pretreated with RNAase yielded substantial background hybridization (Figure 4B and D). In the late secretory phase, the hybridization signal was similar in distribution and intensity to that in the proliferative phase. On the other hand, the hybridization signal was observed predominantly in stromal cells in both normal decidua parietalis and tubal pregnancy decidua (Figure 4E, F, H and I). Endothelial cells and vascular smooth muscle cells did not express MT1-MMP mRNA at any time during the menstrual cycle or early pregnancy. Neither sense probes nor sections pretreated with RNAase yielded substantial background hybridization (Figure 4G and J).
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Immunohistochemistry
Only epithelial cells were immunoreactive for cytokeratin in normally cycling endometrium, decidua parietalis, and tubal pregnancy decidua (illustrated only for decidua parietalis, Figure 5G
). Throughout the menstrual cycle, epithelial cells stained for MT1-MMP protein (Figure 5A and B), while stromal cells in normally cycling endometrium showed no staining. In decidua parietalis, both epithelial cells and stromal cells stained for MT1-MMP (Figure 5C and E). The same was true for tubal pregnancy decidua (Figure 5D and F). Vascular endothelial and smooth muscle cells of vessels showed no staining in normally cycling endometrium, decidua parietalis, or tubal pregnancy decidua.
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Discussion
The two most important findings in this report are as follows. Firstly, expression of MT1-MMP mRNA did not show any quantitative changes in endometrium during the normal menstrual cycle, or in decidua parietalis or tubal pregnancy decidua. Secondly, localization of MT1-MMP mRNA and protein in these tissues differed dramatically between cycling endometrium and decidua in the absence of direct contact with trophoblastic cells.
The expression level of MT1-MMP mRNA in endometrium did not alter during the menstrual cycle, similar to previous conclusions (Rodgers et al., 1994) from a qualitative study with respect to MMP-2 mRNA. MT1-MMP mRNA was expressed mainly in the epithelium with only minimal stromal expression throughout the menstrual cycle. The mRNA hybridization signal, however, was detected clearly in stromal cells in decidua parietalis and in tubal pregnancy decidua. The mRNA hybridization signal seemed to be increased in stroma of early pregnancy decidua compared with that in epithelium of normally cycling endometrium. However, the number of positive cells counted was found to be similar between epithelium of normally cycling endometrium and stroma of early pregnancy decidua. Moreover, each cell showed the same strength mRNA hybridization signal in epithelium as that in stroma. Similar results were recognized in other parts of tissue samples. These findings seem to show that the RT–PCR result is compatible with that of in-situ hybridization.
With regard to the localization of MT1-MMP protein, MT1-MMP immunoreactivity was detected in the epithelial cells alone throughout the menstrual cycles. In decidua parietalis and tubal pregnancy decidua, MT1-MMP protein was detected in stromal as well as epithelial cells. In contrast to hybridization studies, immunohistochemistry detected MT1-MMP protein in both stromal and epithelial cells. The difference in localization between MT1-MMP mRNA and protein may reflect a low-level expression in epithelial cells of early pregnancy decidua which, as in the case of tumour cells, is undetectable by in-situ hybridization (Polette and Birembaut, 1998).
Throughout the process of implantation and early placentation, trophoblastic cells penetrate the basement membrane of epithelium and invade the stromal compartment of the uterus. Penetration ability is mediated by MMPs in a manner resembling events in malignant tumour invasion (Yagel et al., 1988; Burrows et al., 1996; Lala and Hamilton, 1996). Expression of MT1-MMP on cell surfaces may greatly enhance the localized pericellular degradation of extracellular matrix macromolecules during cell migration (Nagase, 1997). If so, proMMP-2 secreted by trophoblast could be activated by MT1-MMP in the epithelium. The activated MMP-2 would degrade the basement membrane of the epithelium. An embryo attached to the epithelium would continue to secrete proMMP-2 which would be activated by MT1-MMP in decidualizing cells. These processes would allow trophoblasts and the embryo to degrade the extracellular matrix surrounding decidualized cells and invade the stroma.
A few studies have examined the transcriptional regulation of MT1-MMPs. Growth factors and cytokines, e.g. interleukin-1ß, epidermal growth factor, basic fibroblast growth factor, and transforming growth factor-ß, negligibly affect mRNA levels of MT1-MMP, although transforming growth factor-
slightly increases MT1-MMP gene expression in HT-1080 cells (Lohi et al., 1996). In our study, expression of MT1-MMP mRNA and protein was localized in epithelial cells throughout the menstrual cycle, while in decidua the localization of MT1-MMP mRNA and protein shifted from epithelial cells to stromal cells in no direct contact with trophoblasts. MT1-MMP mRNA and protein are also reported to be expressed in stromal cells of decidua vera, with which trophoblasts are in direct contact (Nawrocki et al., 1996). Our results showed that the expression level of both MT1-MMP and the localization of this enzyme, were similar in decidua pareitalis and ectopic pregnancy decidua. In the context of our results, invasion of trophoblasts probably was not directly responsible for expression of the MT1-MMP gene in the endometrium and decidua. Rather, soluble factors may have affected transcriptional regulation of the enzyme. Whether this effect is dependent upon human chorionic gonadotrophin (HCG) would be important to determine.
MT1-MMP mRNA is expressed in certain tissues in the process of healing from injury or remodelling of the extracellular matrices ECM (Hayashi et al., 1998; Madlener et al., 1998; Pap et al., 1998; Tyagi et al., 1998). Interestingly, MT1-MMP mRNA exhibited a distribution similar to that of -smooth muscle actin in proliferating mesangial cells and fibroblasts in granulation tissue (Hayashi et al., 1998; Madlener et al., 1998), and -smooth muscle actin is also induced in endometrial stromal cells in the process of decidualization (Oliver et al., 1999). These changes in -smooth muscle actin in endometrial stromal cells, mesangial cells, and granulation tissue cells appear to be closely associated with MT1-MMP gene expression.
The functions and substrates of MT1-MMP are complex, varied, and not completely known. However, MT1-MMP appears to play a dual role in extracellular matrix remodelling through activation of proMMP-2 and proMMP-13, and on the other hand through direct cleavage of extracellular matrix components, e.g. collagen I, II, III, fibronectin, laminin-1, vitronectin, and dermatan sulphate proteoglycan (Nagase, 1997; Seiki, 1999). Activation of proMMP-2 by MT1-MMP is the result of a very complicated process. Many factors including the pericellular concentration of TIMP-2 (Strongin et al., 1995; Butler et al., 1998; Zucker et al., 1998), plasmin activity for autoproteolysis (Baramova et al., 1997; Mazzieri et al., 1997), or direct binding of the soluble catalytic domain of MT1-MMP to proMMP-2 (Sato et al., 1996) are directly or indirectly involved in this process. Our data showed that MT1-MMP was expressed in the endometrium throughout the menstrual cycle and early pregnancy, as has been shown for TIMP-2 and proMMP-2 (Rodgers et al., 1994; Nawrocki et al., 1996; Bjorn et al., 1997; Salamonsen et al., 1997; Zhang et al., 1997). Simultaneous expression of MT1-MMP and MMP-2, however, does not in itself prove that co-expression results in activation of proMMP-2, as described above.
In summary, we studied the expression pattern of MT1-MMP in endometrium throughout the menstrual cycle and in early pregnancy by quantitative RT–PCR, in-situ hybridization, and immunohistochemistry. Our findings showed that even in decidua lacking trophoblastic contact, pregnancy shifted the localization of MT1-MMP mRNA and protein from epithelial cells to decidual stromal cells without significantly changing the overall level of MT1-MMP mRNA expression. These data indicate that MT1-MMP in the endometrium and decidua may be important for attachment of the embryo to the epithelium and invasion of the trophoblast into the stroma, as well as for ECM remodelling in the endometrium and decidua. In future studies we hope to verify the transcriptional regulation of MT1-MMP in the endometrium and decidua, and also to measure the activity of MMP-2 in vivo
Acknowledgments
This work is supported in part by the Program for Promotion of Basic Research Activities for Innovative Biosciences (PROBRAIN) and Grants-in-Aid for Scientific Research (No. 11877283) from the Ministry of Education, Science and Culture of Japan. We thank Drs Hasegawa and Oofusa for their suggestions on the techniques of in-situ hybridization.
Notes
3 To whom correspondence should be addressed. E-mail: tetsuaki{at}mcai.med.hiroshima-u.ac.jp 
References
Baramova, E.N., Bajou, K., Remacle, C. et al. (1997) Involvement of PA/plasmin system in the processing of pro-MMP-9 and in the second step of pro-MMP-2 activation. FEBS Lett., 405, 157–162.[Web of Science][Medline]
Butler, G.S., Butler, M.J. Atkinson, S.J. et al. (1998) The TIMP-2 membrane type 1 metalloproteinase `receptor' regulates the concentration and efficient activation of progelatinase A. J. Biol. Chem., 273, 871–880.
Bjorn, S.F., Hastrup, N., Lund, L.R. et al. (1997) Co-ordinated expression of MMP-2 and its putative activator, MT1-MMP, in human placentation. Mol. Hum. Reprod., 3, 713–723.
Burrows, T.D., King, A. and Loke, Y.W. (1996) Trophoblast migration during human placental implantation. Hum. Reprod. Update, 2, 307–321.
Cao, J., Sato, H., Takino, T. and Seiki, M. (1995) The C-terminal region of membrane type matrix metalloproteinase is a functional transmembrane domain required for pro-gelatinase A activation. J. Biol. Chem., 270, 801–805.
Chomcznski, P. and Sacchi, N. (1987) Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal. Biochem., 162, 156–159.[Web of Science][Medline]
Fortunato, S.J., Menon, R. and Lombardi, S.J. (1998) Expression of a progelatinase activator (MT1-MMP) in human fetal membranes. Am. J. Reprod. Immunol., 39, 316–322.
Hayashi, K., Osada, S., Shofuda, K. et al. (1998) Enhanced expression of membrane type-1 matrix metalloproteinase in mesangial proliferative glomerulonephritis. J. Am. Soc. Nephrol., 9, 2262–2271.[Abstract]
Hulboy, D.L., Rudolph, L.A. and Matrisian, L.M. (1997) Matrix metalloproteinases as mediators of reproductive function. Mol. Hum. Reprod., 3, 27–45.
Lala, P.K. and Hamilton, G.S. (1996) Growth factors, proteases and protease inhibitors in the maternal fetal dialogue. Placenta, 17, 545–555.[Web of Science][Medline]
Lohi, J., Lehti, K., Westermarck, J. et al. (1996) Regulation of membrane-type matrix metalloproteinase-1 expression by growth factors and phorbal 12-myristate 13-acetate. Eur. J. Biochem., 239, 239–247.[Web of Science][Medline]
Madlener,M. Parks, W.C. and Werner, S. (1998) Matrix Metalloproteinases (MMPs) and their physiological inhibitors (TIMPs) are differentially expressed during excisional skin wound repair. Exp. Cell Res., 242, 201–210.[Web of Science][Medline]
Mazzieri, R., Masiero, L., Zanetta, L. et al. (1997) Control of type IV collagenase activity by components of the urokinase-plasmin system: a regulatory mechanism with cell-bound reactants. EMBO J., 16, 2319–2332.[Web of Science][Medline]
Nagase, H. (1997) Activation mechanisms of matrix metalloproteinases. Biol. Chem., 378, 151–160.
Nawrocki, B., Polette, M., Marchand, V. et al. (1996) Membrane-type matrix metalloproteinase-1 expression at the site of human placentation. Placenta, 17, 565–572.[Web of Science][Medline]
Noyes, R.W., Hertig, A.T. and Rock, J. (1950) Dating an endometrial biopsy. Fertil. Steril., 1, 3–25.
Oliver, C., Montes, M.J., Galindo, J.A. et al. (1999) Human decidual stromal cells express -smooth muscle actin and show ultrastructural similarities with myofibroblasts. Hum. Reprod., 14, 1599–1605.
Pap, T., Pap, G., Hummel, K.M. et al. (1999) Membrane-type-1 matrix metalloproteinase is abundantly expressed in fibroblasts and osteoclasts at the bone-implant interface of aseptically loosened joint arthroplasties in situ. J. Rheumatol., 26, 166–169.[Web of Science][Medline]
Polette, M. and Birembaut, P. (1998) Membrane-type metalloproteinases in tumor invasion. Int. J. Biochem. Cell Biol., 30, 1195–1202.[Web of Science][Medline]
Rodgers, W.H., Matrisian, L.M., Giudice, L.C. et al. (1994) Patterns of matrix metalloproteinase expression in cycling endometrium imply differential functions and regulation by steroid hormones. J. Clin. Invest., 94, 946–953.
Salamonsen, L.A., Butt, A.R., Hammond, F.R. et al. (1997) Production of endometrial matrix metalloproteinases, but not their tissue inhibitors, is modulated by progesterone withdrawal in an in vitro model for menstruation. J. Clin. Endocrinol. Metab., 82, 1409–1415.
Sato, H., Takino, T., Okada, Y. et al. (1994) A matrix metalloproteinase expressed on the surface of invasive tumor cells. Nature (London), 370, 61–65.[Medline]
Sato, H., Takino, T., Imai, K. et al. (1996) Cell surface binding and activation of gelatinase A induced by expression of membrane-type-1-matrix metalloproteinase (MT1-MMP). FEBS Lett., 385, 238–240.[Web of Science][Medline]
Seiki, M. (1999) Membrane-type matrix metalloproteinases. APMIS, 107, 137–143.[Web of Science][Medline]
Strongin, A.Y., Collier, I., Bannikov, G. et al. (1995) Mechanism of cell surface activation of 72-kDa type IV collagenase. J. Biol. Chem., 270, 5331–5338.
Tokuraku, M., Sato, H., Murakami, S. et al. (1995) Activation of the precursor of gelatinase A/72 kDa type IV collagenase/MMP-2 in lung carcinomas correlates with the expression of membrane-type matrix metalloproteinase (MT-MMP) and with lymph node metastasis. Int. J. Cancer (Pred. Oncol.), 64, 355–359.[Web of Science][Medline]
Tyagi, S.C., Lewis, K., Pikes, D. et al. (1998) Stretch-induced membrane type matrix metalloproteinase and tissue plasminogen activator in cardiac fibroblast cells. J. Cell. Physiol., 176, 374–382.[Web of Science][Medline]
Werb, Z., Vu, T.H., Rinkenberger, J.L. and Coussens, L.M. (1999) Matrix-degrading proteases and angiogenesis during development and tumor formation. APMIS, 107, 11–18.[Web of Science][Medline]
Yagel, S., Parhar, R.S. and Jeffrey, J. (1988) Normal nonmetastatic human trophoblast cells share in vitro invasive properties of malignant cells. J. Cell. Physiol., 136, 445–462.
Zhang, J. and Salamonsen, L.A. (1997) Tissue inhibitor of metalloproteinases (TIMP)-1, -2, -3 in human endometrium during the menstrual cycle. Mol. Hum. Reprod., 3, 735–741.
Zucker, S., Drew, M., Conner, C. et al. (1998) Tissue inhibitor of metalloproteinase-2 (TIMP-2) binds to the catalytic domain of the cell surface receptor, membrane type 1-matrix metalloproteinase (MT1-MMP). J. Biol. Chem., 273, 1216–1222.
Submitted on September 5, 2000; accepted on December 27, 2000.
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 Y. Noguchi, T. Sato, M. Hirata, T. Hara, K. Ohama, and A. Ito Identification and Characterization of Extracellular Matrix Metalloproteinase Inducer in Human Endometrium during the Menstrual Cycle in Vivo and in Vitro J. Clin. Endocrinol. Metab., December 1, 2003; 88(12): 6063 - 6072. [Abstract] [Full Text] [PDF]
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 T. E. Curry Jr. and K. G. Osteen The Matrix Metalloproteinase System: Changes, Regulation, and Impact throughout the Ovarian and Uterine Reproductive Cycle Endocr. Rev., August 1, 2003; 24(4): 428 - 465. [Abstract] [Full Text] [PDF]
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