Calmodulin regulates the interleukin 1-induced procollagenase production in human uterine cervical fibroblasts

Tamoxifen Upregulates Collagenase Gene Expression in Human Dermal Fibroblasts

Background

Tamoxifen is a known inhibitor of fibroblast transforming growth factor beta biosynthesis and wound scar formation. Tamoxifen is also known to be an estrogen antagonist and protein kinase C (PKC) inhibitor. Cells treated with tamoxifen and other PKC/calmodulin inhibitors depolymerize their membrane focal adhesion complexes and cytoskeletal protein structures. These effects result in substrate detachment, cell shape rounding, and upregulation of collagenase synthesis and extracellular matrix degradation. The purpose of our study was to test the hypothesis that tamoxifen treatment of human foreskin fibroblasts results in alteration of cytoskeletal protein organization, cell detachment and rounding, and increased collagenase synthesis similar to known PKC/calmodulin inhibitors such as H-7.

Methods

We characterized the effects of PKC/calmodulin inhibitors tamoxifen and H-7 on human dermal fibroblast morphology, cytoskeletal protein organization, and collagenase gene expression in monolayer culture and within collagen gels.

Results

We found that fibroblasts responded to tamoxifen by initiation of actin filament depolymerization followed by alteration from spindle to spheroidal shapes. This change in cell shape led to increased collagenase synthesis in cells treated with either tamoxifen or H-7 compared with controls. There was also a 23% increase of hydroxyproline release from tamoxifen-treated fibroblast-populated collagen matrices.

Conclusions

Tamoxifen may reduce scarring by inhibiting fibroblast PKC/calmodulin activity, which down-regulates pro-fibrotic transforming growth factor beta signaling and upregulates collagenase production. These effects mimic those of the known PKC/calmodulin inhibitor H-7. Overall, these findings suggest that tamoxifen and its analogues are promising agents for clinical investigation as small molecule regulators of fibrosis and scarring disorders.

MicroRNA expression profiling of the human uterine cervix after term labor and delivery

OBJECTIVE

MicroRNAs (miRNAs) are noncoding RNAs involved in posttranscriptional regulation of target genes. The objective of this study was to determine the miRNA expression profile of the human uterine cervix after spontaneous term labor (TL).

STUDY DESIGN

The miRNA expression pattern of cervical tissue was characterized using microarrays. Samples were collected at term from patients with (n = 8) and without (n = 9) TL. Moderated t tests and false discovery rate correction were applied. Results were confirmed using quantitative reverse transcriptase-polymerase chain reaction.

RESULTS

A total of 226 miRNAs were expressed in human cervical tissue. miR-223, miR-34b, and miR-34c were overexpressed in cervical tissue of patients with TL compared to those without. Quantitative reverse transcriptase-polymerase chain reaction assays confirmed these findings (miR-223 [fold change {FC} = 5.7], miR-34b [FC = 4.5], miR-34c [FC = 6.2]; P < .001).

CONCLUSION

This is the first report of miRNA expression in the human uterine cervix in pregnancy. Cervical remodeling after TL and delivery was associated with changes in miR-223, miR-34b, and miR-34c.

Cytotoxicity and apoptotic inducibility of Vitex agnus-castus fruit extract in cultured human normal and cancer cells and effect on growth

A crude extract was prepared with ethanol from dried ripened Vitex agnus-castus fruits growing in Israel (Vitex extract). Cytotoxicity of the extract against human uterine cervical canal fibroblast (HCF), human embryo fibroblast (HE-21), ovarian cancer (MCF-7), cervical carcinoma (SKG-3a), breast carcinoma (SKOV-3), gastric signet ring carcinoma (KATO-III), colon carcinoma (COLO 201), and small cell lung carcinoma (Lu-134-A-H) cells was examined. After culture for 24 h (logarithmic growth phase) or 72 h (stationary growth phase), the cells were treated with various concentrations of Vitex extract. In both growth phases, higher growth activity of cells and more cytotoxic activity of Vitex extract were seen. The cytotoxic activity against stationary growth-phase cells was less than that against logarithmic growth-phase cells. DNA fragmentation of Vitex extract-treated cells was seen in SKOV-3, KATO-III, COLO 201, and Lu-134-A-H cells. The DNA fragmentation in Vitex extract-treated KATO-III cells was inhibited by the presence of the antioxidative reagent pyrrolidine dithiocarbamate or N-acetyl-L-cysteine (NAC). Western blotting analysis showed that in Vitex extract-treated KATO-III cells, the presence of NAC also inhibited the expression of heme oxygenase-1 and the active forms of caspases-3, -8 and -9. It is concluded that the cytotoxic activity of Vitex extract may be attributed to the effect on cell growth, that cell death occurs through apoptosis, and that this apoptotic cell death may be attributed to increased intracellular oxidation by Vitex extract treatment.

Furin-independent pathway of membrane type 1-matrix metalloproteinase activation in rabbit dermal fibroblasts

We investigated the gene expression and intracellular activity of processing protease furin and its involvement in the process of membrane type 1-matrix metalloproteinase (MT1-MMP) activation in rabbit dermal fibroblasts. When the rabbit fibroblasts were treated with concanavalin A (ConA), pro-MMP-2 was converted to an active 62-kDa MMP-2 through the appearance of a 64-kDa intermediate MMP-2. The ConA-induced pro-MMP-2 activation resulted from increasing the gene expression and production of MT1-MMP in the rabbit fibroblasts. Reverse transcriptase-polymerase chain reaction demonstrated that in rabbit dermal fibroblasts furin mRNA was detected and, unlike MT1-MMP, was not increased by ConA. These findings are further supported by the fact that the intracellular furin activity also was constitutively detected and was unchanged by the ConA treatment. Very similar phenomena were also observed in human uterine cervical fibroblasts, which are known to produce MT1-MMP by ConA stimulation. These results suggest that the expression of the furin gene and the intracellular activity are not regulated by ConA. On the other hand, neither a synthetic furin inhibitor, decanoyl-RVKR-CH(2)Cl (25-100 microM) nor a furin antisense oligonucleotide (40 microM) inhibited the MT1-MMP-mediated pro-MMP-2 activation in ConA-treated rabbit dermal fibroblasts, whereas these compounds interfered with pro-MMP-2 activation in ConA-treated human uterine cervical fibroblasts. Nonetheless, the furin antisense oligonucleotide completely suppressed furin gene expression in both rabbit and human fibroblasts. These results suggest that furin does not participate in the process of MT1-MMP activation induced by ConA in rabbit dermal fibroblasts.

Plasma membrane-bound tissue inhibitor of metalloproteinases (TIMP)-2 specifically inhibits matrix metalloproteinase 2 (gelatinase A) activated on the cell surface

The cell-surface activation of pro-matrix metalloproteinase 2 (pro-MMP-2) is considered to be critical for cell migration and invasion. Treatment of human uterine cervical fibroblasts with concanavalin A activates pro-MMP-2 on the cell surface by converting it to the 65-kDa form with a minor form of 45 kDa. However, the 65-kDa MMP-2 was inactivated by tissue inhibitor of metalloproteinases (TIMP)-2 that was bound to the plasma membrane upon concanavalin A treatment. TIMP-2 binds to the plasma membrane through its N-terminal domain by two different modes of interaction as follows: one is sensitive to a hydroxamate (HXM) inhibitor of MMPs and the other is HXM-insensitive. TIMP-2 bound to the membrane in a HXM-insensitive manner, comprising about 40-50% of TIMP-2 on the membrane, is the inhibitor of the cell surface-activated MMP-2. It, however, does not inhibit MMP-3, MMP-9, and the 45-kDa MMP-2 lacking the C-terminal domain. The inhibition of the 65-kDa MMP-2 by TIMP-2 is initiated by the interaction of their C-terminal domains. Subsequently, the MMP-2.TIMP-2 complex is released from the membrane, and the activity of MMP-2 is blocked by TIMP-2. In the presence of collagen types I, II, III, V, or gelatin, the rate of inhibition of the 65-kDa MMP-2 by the membrane-bound TIMP-2 decreased considerably. These results suggest that the pericellular activity of MMP-2 is tightly regulated by membrane-bound TIMP-2 and surrounding extracellular matrix components.

Presence of Vicia graminea lectin- and Vicia unijuga lectin-binding (Vgu) glycoproteins in human fetal membranes and some of their biochemical properties

We have previously reported that Vicia graminea lectin (VGA)- and Vicia unijuga lectin (VUA)-binding glycoproteins (Vgu glycoproteins), malignant tumor-associated antigens, exist in human meconium and amniotic fluid. To examine the origin of Vgu glycoprotein, their presence, some of their chemical and serological properties and their biosynthesis in the human fetal membrane, amnion and chorion laeve and accompanying membrane cells were examined. Perchloric acid-soluble fractions were prepared from human amnion and chorion laeve, after which VUA-binding components (Vgu glycoproteins) were separated by HPLC and affinity chromatography using immobilized VUA. Biosynthesis of the antigens in primary cultured cells prepared from the amnion and chorion laeve were examined by pulse-labeling and immunoprecipitation using immobilized VUA and compared with those in cultured human cancer cells. The results indicated that the serological properties of VUA-binding components in fetal membranes were similar to those of meconium and amniotic fluid, that many molecular species of VUA-binding components were synthesized in amnion and chorion laeve cells and that about 40-50% of antigens synthesized are secreted from cells while antigens synthesized in cultured cancer cells human were hardly secreted with more than 95% of the antigens remaining in the cells. From these results, we concluded that a large part of Vgu glycoproteins found in amniotic fluid is synthesized in cells of the amnion and chorion laeve and secreted into the fluid, and that Vgu glycoproteins synthesized in cancer cells were not secreted, rather they were retained in the cells.

Urinary trypsin inhibitor suppresses the production of interstitial procollagenase/proMMP-1 and prostromelysin 1/proMMP-3 in human uterine cervical fibroblasts and chorionic cells

The mechanisms by which urinary trypsin inhibitor (UTI) prevents preterm premature rupture of fetal membrane and premature cervical ripening were investigated. We, therefore, examined the effects of UTI on the production of matrix metalloproteinases (MMPs) which closely participate in the breakdown of extracellular matrix in cultured human uterine cervical fibroblasts and human chorionic cells. UTI suppressed specifically the production of interstitial procollagenase/proMMP-1 and prostromelysin 1/proMMP-3 from both cells in a dose-dependent manner (0.32-1.28 microM). This suppression was accompanied by a decrease in steady-state levels of their mRNAs. These results indicate for the first time that UTI down-regulates the production of proMMP-1 and proMMP-3 accompanying with the decrease in the expression of their mRNAs, and therefore UTI actually participates in the maintenance of fetal membranes and/or uterine cervix by overall suppression of MMP production along with the known inhibitory actions towards serine proteinases.

Tumor necrosis factor alpha (TNFalpha) induces pro-matrix metalloproteinase 9 production in human uterine cervical fibroblasts but interleukin 1alpha antagonizes the inductive effect of TNFalpha

We have examined the regulation of precursor of matrix metalloproteinase 9 (proMMP-9)/progelatinase B production by tumor necrosis factor alpha (TNFalpha) and interleukin 1alpha (IL-1alpha) using human uterine cervical fibroblasts. TNFalpha, but not IL-1alpha, induces the production of proMMP-9 in the cervical cells. IL-alpha, however, suppresses the TNFalpha-induced proMMP-9 production. 12-0-tetradecanoylphorbol 13-acetate (TPA) also stimulates the cervical cells to produce proMMP-9, and IL-1alpha synergistically enhances its production. TNFalpha-induced proMMP-9 production is not mediated by protein kinase C (PKC), whereas the effect of IL-1alpha is through PKC. By contrast, proMMP-3/prostromelysin 1 is up-regulated by TNFalpha or TPA in the presence of IL-1alpha, whose modulation is PKC-dependent. The suppressive effect of IL-1alpha on the TNFalpha-induced proMMP-9 production is a new biological effect of IL-1 on MMP production.

Biochemical changes in the cervical mucus after application of laminaria tent

BACKGROUND

This research was aimed to study the biochemical changes in cervical mucus after application of laminaria tent.

MATERIAL AND METHODS

Cervical mucus was collected before and after insertion of laminaria tent from 20 normal pregnant women in the first and second trimesters. Interleukin-1 beta, IL-8, collagenase activity, elastase activity, PGE2 and PGF2 alpha were measured in the collected samples. Laminaria tent was also inserted in one vaginal cervix of five non-pregnant rabbits and the clinical and histological changes were compared with five non-treated rabbits. Collagen contents were assessed histologically and Leukocyte number was counted.

RESULTS

IL-1 beta and IL-8 and elastase activity were significantly increased after insertion of laminaria (p<0.0001 and 0.001 respectively). Collagenase activity was not significantly changed. Whereas concentration of PGE2 and PGF2 alpha in the mucus were markedly increased (p<0.0001 and 0.001 respectively). Collagen contents were significantly decreased in laminaria and opposite side cervices (p<0.0001). No significant changes in leukocyte count could be observed in treated and non treated cervices.

CONCLUSIONS

Insertion of laminaria leads to increase concentration of IL-1 beta, IL-8, PGE2, PGF2 alpha and elastase activity. Mechanical stretching of the cervix and biochemical changes in cervical mucus may explain the mechanism of cervical ripening induced by laminaria.

Translational augmentation of pro-matrix metalloproteinase 3 (prostromelysin 1) and tissue inhibitor of metalloproteinases (TIMP)-1 mRNAs induced by epidermal growth factor in human uterine cervical fibroblasts

The mechanisms by which epidermal growth factor (EGF) enhances the production of pro-matrix metalloproteinase 3 (proMMP-3/prostromelysin 1) and tissue inhibitor of metalloproteinases (TIMP)-1 were investigated using human uterine cervical fibroblasts. The treatment of the cells with EGF for 24 h resulted in about 5-6-fold increase in the production of proMMP-3 and TIMP-1 compared with the untreated control cells. This increase was accompanied by an increase of proMMP-3 and TIMP-1 mRNAs. However, an about 3- and 2-fold increase in the production of proMMP-3 and TIMP-1, respectively, was observed as early as 1 h after the treatment of the cells with EGF, and it was not accompanied by any apparent increase in proMMP-3 and TIMP-1 mRNAs. This early effect of EGF on the enhanced production of proMMP-3 and TIMP-1 was not inhibited by actinomycin D, even though actinomycin D inhibited the synthesis of the total RNA in both the EGF-treated and untreated cells. These results indicate that EGF enhances the apparent production of proMMP-3 and TIMP-1 by two mechanisms: one by the accelerated translation of their mRNAs; and the other by the enhanced transcription of their genes. The former event takes place much earlier than the latter.

Co-culture of human breast adenocarcinoma MCF-7 cells and human dermal fibroblasts enhances the production of matrix metalloproteinases 1, 2 and 3 in fibroblasts

No measurable amounts of matrix metalloproteinases (MMPs) were produced by human breast adenocarcinoma cell lines MCF-7 and BT-20 in culture. When MCF-7 cells were co-cultured with human dermal fibroblasts enhanced production of precursors of MMP-1 (interstitial collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin 1) and tissue inhibitor of metalloproteinase type 1 (TIMP-1) was observed. Immunohistochemical studies indicated that these pro-MMPs originated primarily from the fibroblasts, suggesting that MCF-7 cells have a stimulatory effect on stromal cells to produce at least three pro-MMPs and TIMP-1. BT-20 cells also enhanced the production of pro-MMP-2 and TIMP-1 in the dermal fibroblasts, but not of pro-MMP-1 and pro-MMP-3. Normal mammary epithelial cells promoted only TIMP-1 production. To investigate further the stimulatory factors from MCF-7 cells, the conditioned medium and the cell membrane were prepared and examined. The cell membrane fraction enhanced the production of pro-MMP-1 and -3 and TIMP-1, but not of pro-MMP-2. The conditioned medium, on the other hand, augmented the production of all four proteins in the fibroblasts. These observations suggest that breast adenocarcinoma MCF-7 cells in culture produce both soluble and membrane-bound factor(s) which stimulate the production of pro-MMPs and TIMP-1 in neighbouring stromal cells, but the factor(s) released into the medium and that associated with cell membranes are probably different. Such communication between the normal and malignant cell types may, in part, assist the cancer cells to invade and metastasise.

The presence of cervical and vaginal fetal fibronectin predicts preterm delivery in an inner-city obstetric population

OBJECTIVE

It has previously been shown that fibronectin bearing a specific oncofetal domain is present at the chorionic-decidual interface and that its release into cervical and vaginal secretions accurately predicts preterm delivery in patients with uterine contractions. This study examines whether serial assessment of cervical and vaginal fetal fibronectin allows for the prediction of preterm delivery in symptom-free patients derived from an inner-city, general obstetric population.

STUDY DESIGN

Cervical and vaginal samples were obtained from 429 consenting patients who received routine prenatal care between 24 and 37 weeks' gestation. A sensitive immunoassay was used to quantitate cervical and vaginal fetal fibronectin levels, and clinicians were blinded to fetal fibronectin results. Post hoc receiver operating characteristic curve analysis was used to determine which sample site (cervical or vaginal), fetal fibronectin concentration, and number of consecutive positive samples optimized screening efficacy. Logistic regression was employed to determine whether fetal fibronectin was an independent predictor of preterm delivery.

RESULTS

The spontaneous preterm delivery rate was 11% (49/429). Among the 326 patients sampled within 28 days of delivery, receiver operating characteristic curve analysis indicated that the presence of a single cervical fetal fibronectin value > 60 ng/ml between 24 and 36 weeks' gestation predicted preterm delivery with a sensitivity of 73%, a specificity of 72%, and positive and negative predictive values of 25% and 95%, respectively. A vaginal fetal fibronectin value > 50 ng/ml predicted preterm delivery with a sensitivity of 68%, a specificity of 80%, and positive and negative predictive values of 30% and 95%, respectively. Cervical and vaginal fetal fibronectin predicted preterm deliveries resulting from both membrane rupture and preterm labor with intact membranes. A positive fetal fibronectin result preceded preterm delivery by 3.4 (+/- 3.2) weeks. Stepwise logistic regression demonstrated that cervical and vaginal fetal fibronectin levels were independent predictors of preterm delivery with adjusted odds ratios of 8.9 (95% confidence interval 3.6 to 22.1) and 6.0 (95% confidence interval 2.6 to 13.7), respectively.

CONCLUSIONS

Among patients undergoing monthly cervical and vaginal sampling between 24 and 36 weeks' gestation, the presence of fetal fibronectin is a sensitive and specific predictor of preterm delivery.

Double-blind; placebo-controlled trial of piperacillin prophylaxis in preterm membrane rupture

OBJECTIVE

We attempted to test whether antibiotic therapy prolongs pregnancy in preterm premature rupture of membranes, because preterm premature rupture of membranes is frequently associated with chorionic-decidual infection.

STUDY DESIGN

Women with preterm premature rupture of membranes and a singleton gestation at 24 to 34 completed weeks were randomized to receive either piperacillin 3 gm or placebo intravenously every 6 hours for 72 hours and were managed conservatively until spontaneous delivery, chorioamnionitis, or fetal distress.

RESULTS

Between January 1987 and January 1992, a total of 75 patients were randomized to receive piperacillin (n = 38) or placebo (n = 37). There were no differences between the piperacillin group and the placebo group in mean gestational age at randomization (30.2 +/- 3 vs 30.3 +/- 2.9 weeks). However, a greater number of patients had pregnancy prolonged beyond 7 days (42.1% vs 10.8% p = 0.005) and the mean latency period was significantly prolonged (11.4 +/- 18.8 vs 6.1 +/- 13.6 days, p = 0.001) in the piperacillin group compared with the control groups.

CONCLUSIONS

Use of intravenous piperacillin for 72 hours in preterm premature rupture of membranes significantly prolongs the latency period between membrane rupture and delivery.

New approaches to the prediction of preterm delivery

Current approaches to the detection of patients at risk for preterm delivery (PTD) have focused on the diagnosis of preterm labor. However, these approaches are complicated by treatment biases and our inability to convincingly differentiate preterm labor from Braxton-Hicks contractions. Moreover, preterm labor with intact membranes accounts for only one-half of all spontaneous PTDs since uterine contractions follow preterm premature rupture of the membranes (PROM) in an additional 50% of cases. Clinical dogma holds that the prevention of PTD requires the early detection of at risk patients. However, clinical indicators of PTD risk including cervical change, uterine contractions, vaginal bleeding, maternal demographic featuers and obstetrical history have poor sensitivity and/or specificity. Fortunately, an improved understanding of the association between preterm parturition and cervical, chorionic and decidual extracellular matrix degradation has led to a number of promising new biochemical indices of the proteolytic processes leading to PTD. These include measurement of serum collagenase activity and assessment of cervico-vaginal granulocyte elastase and oncofetal fibronectin levels. It remains to be seen, however, whether an improved detection of patients at risk will lead to a reduction in the occurrence of PTD.

Tumor necrosis factor bifunctionally regulates matrix metalloproteinases and tissue inhibitor of metalloproteinases (TIMP) production by human fibroblasts

The production of tissue inhibitor of metalloproteinases (TIMP) in human uterine cervical fibroblasts was increased by human recombinant tumor necrosis factor alpha (hrTNF) at a low concentration (0.005 ng/ml) but the elevated synthesis was suppressed in a dose-dependent manner at higher concentrations (up to 50 ng/ml). In contrast, the production of collagenase (EC 3.4.24.7) and stromelysin was stimulated at all the corresponding concentrations. In contrast, human recombinant interleukin-1 alpha (hr IL-1, 10 ng/ml) coordinately induced these enzymes and TIMP production. The reduction of the elevated TIMP production by TNF was not due to the inhibition of TIMP secretion. These results suggest that TNF modulates the extracellular matrix degradation in human fibroblasts bifunctionally by the suppression of TIMP production in addition to the acceleration of matrix metalloproteinases production. Furthermore, the fact that TNF and IL-1 differently controlled the production of TIMP suggests that the signal pathway of TNF for TIMP production is different from that of IL-1.

Interleukin 6 enhances the production of tissue inhibitor of metalloproteinases (TIMP) but not that of matrix metalloproteinases by human fibroblasts

We have investigated the effect of interleukin 6 (IL-6) on the synthesis of tissue inhibitor of metalloproteinases (TIMP) and matrix metalloproteinases (MMPs), collagenase (MMP-1) and stromelysin (MMP-3) using human skin and uterine cervical fibroblasts. IL-6 did not modulate the expression of MMPs by these fibroblasts, but the production of TIMP was enhanced by IL-6 in a dose dependent manner, whereas IL-1 stimulated the production of both MMPs and TIMP. The combination of IL-6 and IL-1 further augmented IL-1-induced MMPs and TIMP production. The results provide the first evidence that IL-6 participates in the catabolism of the extracellular matrix components by modulating the effects of IL-1 on MMPs and TIMP synthesis as well as its direct effects on the synthesis of TIMP by connective tissue cells.