Matrix metalloproteinase 9 activity in urine of patients at risk for premature delivery

Elastography and Metalloproteinases in Patients at High Risk of Preterm Labor

Preterm birth (PTB) is the leading cause of perinatal morbidity and mortality. Its etiopathology is multifactorial; therefore, many of the tests contain the assessment of the biochemical factors and ultrasound evaluation of the cervix in patients at risk of preterm delivery. The study aimed at evaluating the socioeconomic data, ultrasound examinations with elastography, plasma concentrations of MMP-8 and MMP-9 metalloproteinases, and vaginal secretions in the control group as well as patients with threatened preterm delivery (high-risk patients). The study included 88 patients hospitalized in the Department of Obstetrics and Pregnancy Pathology, SPSK 1, in Lublin. Patients were qualified to the study group (50) with a transvaginal ultrasonography of cervical length (CL) ≤ 25 mm. The control group (38) were patients with a physiological course of pregnancy with CL > 25 mm. In the study group, the median length of the cervix was 17.49 mm. Elastographic parameters: strain and ratio were 0.20 and 0.83. In the control group, the median length of the cervix was 34.73 mm, while the strain and ratio were 0.20 and 1.23. In the study group, the concentration of MMP-8 in the serum and secretions of the cervix was on average 74.17 and 155.46 ng/mL, but in the control group, it was significantly lower, on average 58.49 and 94.19 ng/mL. The concentration of MMP-9 in both groups was on the same level. Evaluation of the cervical length and measurement of MMP-8 concentration are the methods of predicting preterm delivery in high-risk patients. The use of static elastography did not meet the criteria of a PTB marker.

Human cervicovaginal fluid biomarkers to predict term and preterm labor

Preterm birth (PTB; birth before 37 completed weeks of gestation) remains the major cause of neonatal morbidity and mortality. The current generation of biomarkers predictive of PTB have limited utility. In pregnancy, the human cervicovaginal fluid (CVF) proteome is a reflection of the local biochemical milieu and is influenced by the physical changes occurring in the vagina, cervix and adjacent overlying fetal membranes. Term and preterm labor (PTL) share common pathways of cervical ripening, myometrial activation and fetal membranes rupture leading to birth. We therefore hypothesize that CVF biomarkers predictive of labor may be similar in both the term and preterm labor setting. In this review, we summarize some of the existing published literature as well as our team's breadth of work utilizing the CVF for the discovery and validation of putative CVF biomarkers predictive of human labor. Our team established an efficient method for collecting serial CVF samples for optimal 2-dimensional gel electrophoresis resolution and analysis. We first embarked on CVF biomarker discovery for the prediction of spontaneous onset of term labor using 2D-electrophoresis and solution array multiple analyte profiling. 2D-electrophoretic analyses were subsequently performed on CVF samples associated with PTB. Several proteins have been successfully validated and demonstrate that these biomarkers are associated with term and PTL and may be predictive of both term and PTL. In addition, the measurement of these putative biomarkers was found to be robust to the influences of vaginal microflora and/or semen. The future development of a multiple biomarker bed-side test would help improve the prediction of PTB and the clinical management of patients.

Urinary matrix metalloproteinase activity is not significantly altered in patients with renal cell carcinoma

OBJECTIVES

Matrix metalloproteinases (MMPs) are proteins that degrade the extracellular matrix and have been shown to be elevated in the urine of patients with cancer. One action of MMPs is the degradation of collagen IV that plays a role in tumor invasion and metastasis. This degradation can be measured by a fluorescent microplate activity assay that has been suggested to identify patients with renal cell carcinoma (RCC). Our aim was to confirm the utility of urinary MMP activity as a diagnostic test for RCC.

METHODS

Urine samples from 21 patients undergoing nephrectomy for renal masses, as well as from 2 patients undergoing retroperitoneal mass excision for presumed local recurrence, were collected. Urine samples from 47 healthy volunteers were also collected. After concentration, the urine samples were incubated with fluorescein-labeled collagen IV. The fluorescence activity in each sample was measured using a conventional fluorescent microplate reader to determine the degree of collagen IV degradation in each specimen.

RESULTS

Of the 21 patients undergoing nephrectomy, 15 had RCC, and both patients undergoing retroperitoneal mass excision had pathologically confirmed RCC recurrence. The mean number of fluorescence units emitted from the urine of patients with RCC was 48,924 units (range 0 to 275,879). The mean number of fluorescence units emitted from the urine of healthy patients was 29,834 units (range 0 to 400,086). This difference was not statistically significant (P = 0.34).

CONCLUSIONS

Despite previous evidence, urinary MMP activity was not an adequate test to identify RCC. Most normal urine samples had significant MMP activity.

Regulation of matrix metalloproteinases (type IV collagenases) and their inhibitors in the virgin, timed pregnant, and postpartum rat uterus and cervix by prostaglandin E(2)-cyclic adenosine monophosphate

OBJECTIVE

Our purpose was to examine whether the type IV collagenases (metalloproteinase [MMP]-2 and MMP-9) and their inhibitors (TIMP-1 and TIMP-2) are regulated by a prostaglandin E(2) (PGE(2))-cyclic adenosine monophosphate (cAMP) mechanism in nonpregnant virgin, preterm and term pregnant and postpartum rats.

STUDY DESIGN

Sprague-Dawley rats were infused with either saline solution or PGE(2) over 24 hours or were noninfused. Plasma and tissue were analyzed for cAMP, MMP-2 and MMP-9, and TIMP-1 and TIMP-2.

RESULTS

PGE(2) evoked elevations in plasma and tissue levels of cAMP and MMP-2 in the preterm and term pregnant rats. MMP-9 levels were elevated in the preterm plasma and uterus, whereas in the term pregnant and postpartum rats, MMP-9 levels were increased in the cervix.

CONCLUSIONS

MMP levels in the pregnant and postpartum rat uterus and cervix are regulated in part by a PGE(2)-cAMP mechanism. Specifically, MMP-9 may be involved in preterm labor, cervical maturity, and involution of the postpartum uterus.

Overexpression of alpha(v)beta6 integrin in serous epithelial ovarian cancer regulates extracellular matrix degradation via the plasminogen activation cascade

Recent evidence suggests that integrins are involved in the multi-step process of tumour metastasis. The biological relevance of alpha(v) integrins and associated beta-subunits in ovarian cancer metastasis was examined by analysing the expression of these cell surface receptors in nine ovarian cancer cell lines and also in the primary human ovarian surface epithelial cell line (HOSE). beta1, beta3 and beta5 subunits were present in all ten ovarian cell lines. beta6 subunit was present at varying levels in eight out of nine cancer cell lines but was absent in the HOSE cell line. Immunohistochemical staining showed that beta6 was present in both non-invasive (borderline) and high-grade ovarian cancer tissues but was absent in benign and normal ovarian tissue. High alpha(v)beta6 integrin expressing ovarian cancer cell lines had high cell surface expression of uPA and uPAR. Ovarian cancer cell lines expressing high to moderate level of alpha(v)beta6 integrin demonstrated ligand-independent enhanced levels of high molecular weight (HMW)-uPA and pro-matrix metalloproteinase 2 and 9 (pro-MMP-2 and pro-MMP-9) expression in the tumour-conditioned medium. High and moderate expression of alpha(v)beta6 integrin correlated with increased plasminogen-dependent degradation of extracellular matrix which could be inhibited by inhibitors of plasmin, uPA and MMPs or by monoclonal antibody against uPA, MMP-9 or alpha(v)beta6 integrin. These results suggest that endogenous de novo expression of alpha(v)beta6 integrin in ovarian cancer cells may contribute to their invasive potential, and that alpha(v)beta6 expression may play a role in ovarian cancer progression and metastasis.