A Noncanonical Role for Plasminogen Activator Inhibitor Type 1 in Obesity-Induced Diabetes

Obesity is a major risk factor for type 2 diabetes because of chronic hepatic inflammation and resultant insulin resistance. Hepatocyte growth factor (HGF) is responsible for resetting hepatic homeostasis after injury following activation by urokinase-type plasminogen activator (u-PA; encoded by the PLAU gene). Plasminogen activator inhibitor type-1 (PAI-1; encoded by the SERPINE1 gene), a u-PA inhibitor and antifibrinolytic agent, is often elevated in obesity and is linked to cardiovascular events. We hypothesized that, in addition to its role in preventing fibrinolysis, elevated PAI-1 inhibits HGF's activation by u-PA and the resultant anti-inflammatory and hepatoprotective properties. Wild-type and PAI-1 knockout (KO) mice on a high-fat diet both became significantly heavier than lean controls; however, the obese KO mice demonstrated improved glucose metabolism compared with wild-type mice. Obese KO mice also exhibited an increase in conversion of latent single-chain HGF to active two-chain HGF, coinciding with an increase in the phosphorylation of the HGF receptor (HGFR or MET, encoded by the MET gene), as well as dampened inflammation. These results strongly suggest that, in addition to its other functions, PAI-mediated inhibition of HGF activation prohibits the resolution of inflammation in the context of obesity-induced type 2 diabetes.

The importance of biomarkers in neonatology

Despite a 35% decline in the mortality rate for infants aged <5 years over the past two decades, every year nearly 40% of all deaths in this age group occur in the neonatal period, defined as the first 28 days of life. New knowledge on molecular and biochemical pathways in neonatal diseases will lead to the discovery of new candidate biomarkers potentially useful in clinical practice. In the era of personalized medicine, biomarkers may play a strategic role in accelerating the decline in neonatal mortality by assessing the risk of developing neonatal diseases, by implementing tailored therapeutic treatment, and by predicting the clinical outcome. However, there is an urgent need to reduce the gap in translating newly acquired knowledge from bench to bedside. Traditional and candidate biomarkers for neonatal sepsis and necrotizing enterocolitis will be discussed in this review, such as C-reactive protein (CRP), procalcitonin (PCT), serum amyloid A (SAA), soluble form of CD14 subtype presepsin (sCD14-ST), lipolysaccharide binding protein (LBP), angiopoietins (Ang)-1 and -2, soluble form of triggering receptor expressed on myeloid cells (sTREM-1), soluble form of urokinase-type plasminogen activator receptor (suPAR), platelet-activating factor (PAF) and calprotectin. New frontiers in managing critically ill newborns may be opened by metabolomics, a diagnostic tool based on the recognition of metabolites contained in biological fluids. Metabolomics represents the passage from a descriptive science to a predictive science, having the potential to translate benchtop research to real clinical benefits.

American Society of Clinical Oncology 2007 update of recommendations for the use of tumor markers in breast cancer

PURPOSE

To update the recommendations for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of breast cancer.

METHODS

For the 2007 update, an Update Committee composed of members from the full Panel was formed to complete the review and analysis of data published since 1999. Computerized literature searches of MEDLINE and the Cochrane Collaboration Library were performed. The Update Committee's literature review focused attention on available systematic reviews and meta-analyses of published tumor marker studies. In general, significant health outcomes (overall survival, disease-free survival, quality of life, lesser toxicity, and cost-effectiveness) were used for making recommendations. Recommendations and

CONCLUSIONS

Thirteen categories of breast tumor markers were considered, six of which were new for the guideline. The following categories showed evidence of clinical utility and were recommended for use in practice: CA 15-3, CA 27.29, carcinoembryonic antigen, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, urokinase plasminogen activator, plasminogen activator inhibitor 1, and certain multiparameter gene expression assays. Not all applications for these markers were supported, however. The following categories demonstrated insufficient evidence to support routine use in clinical practice: DNA/ploidy by flow cytometry, p53, cathepsin D, cyclin E, proteomics, certain multiparameter assays, detection of bone marrow micrometastases, and circulating tumor cells.

The complex between urokinase (uPA) and its type-1 inhibitor (PAI-1) in pulmonary adenocarcinoma: Relation to prognosis

In a lung cancer population comprising tumor tissue from 99 pulmonary adenocarcinoma patients, the relationship between tumor tissue level of the complex formed of urokinase (uPA) and its type-1 inhibitor (PAI-1) and survival was studied. The study included patient material previously investigated for the prognostic impact of PAI-1 on survival. Standard clinical parameters were available and the patients had a median survival time of 25 months. An ELISA established to measure preformed uPA-PAI-1 complexes was applied to the tumor extracts and previously measured data on uPA and PAI-1 levels were available. The amounts of uPA-PAI-1 complex measured in pulmonary adenocarcinoma tissue were within the same range as previously reported in breast cancer tissue (0.11-5.74 ng/mg protein). uPA and PAI-1 levels were weakly correlated to the uPA-PAI-1 complex, r = 0.52 and r = 0.47, respectively, and no relation was found between uPA-PAI-1 complex and any of the clinical parameters. However, a significant prognostic impact of PAI-1 on prognosis was demonstrated (HR = 1.62, p = 0.04). Patients with high PAI-1 and low uPA-PAI-1 complex were found to have a significantly poorer survival than patients with low PAI-1 and high uPA-PAI-1 complex (HR = 3.06, p = 0.01). This is the first investigation of the prognostic impact of uPA-PAI-1 complex in a tumor type other than breast cancer, showing low levels of uPA-PAI-1 complex in combination with high levels of PAI-1 to be associated with poor prognosis. To understand these interactions and the clinical importance of the tissue levels of uPA, PAI-1 and uPA-PAI-1 complex, the results suggest further exploratory studies of the components in pulmonary adenocarcinomas and other cancers.

Nipple aspirate fluid expression of urokinase-type plasminogen activator, plasminogen activator inhibitor-1, and urokinase-type plasminogen activator receptor predicts breast cancer diagnosis and advanced disease

BACKGROUND

Tumor expression of urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1), and uPA receptor (uPAR) are breast cancer prognostic factors. Less is known about their usefulness in breast cancer diagnosis. Nipple aspirate fluid (NAF) is secreted into the breast duct and collected noninvasively, making it potentially useful both in breast cancer diagnosis and prognosis. We determined the association of uPA, PAI-1, and uPAR levels in NAF with breast cancer (1) detection and (2) advanced disease.

METHODS

A total of 88 NAF specimens were collected from women with or without breast cancer, and uPA, PAI-1, and uPAR expression were measured by enzyme-linked immunosorbent assay.

RESULTS

uPA and uPAR were independent predictors of cancer presence; uPAR was also an independent predictor of advanced disease stage. Higher PAI-1 expression in breast cancer that was found with univariate analysis was not observed after logistic regression was applied.

CONCLUSIONS

NAF evaluation of uPA, uPAR, and, perhaps, PAI-1 (significant only in univariate analysis) may provide useful breast cancer diagnostic and prognostic information.

High tumor tissue concentration of urokinase plasminogen activator receptor is associated with good prognosis in patients with ovarian cancer

The urokinase plasminogen activator (uPA) system is involved in tumor growth and metastasis. We assayed the components of the uPA system in homogenates of 64 primary epithelial ovarian tumors and 5 metastases and evaluated the association of these parameters to prognosis in the 51 malignant cases. The levels of uPA, PAI-2 and the uPA:PAI-1 complex increased with progressive loss of histological differentiation (p(trend) <0.001, <0.05 and <0.001). The level of PAI-1 was higher in poorly than in well/moderately differentiated tumors (p = 0.03). The content of uPAR was lower in benign tumors as compared to borderline malignancies (p = 0.002), invasive primary tumors (p < 0.001), and metastases (p = 0.002). Surprisingly, the level of uPAR was lower in poorly differentiated as compared to both borderline (p = 0.01) and well differentiated malignant tumors (p = 0.005). Also, the level of uPAR was lower in advanced as compared to early stages of the disease (p(trend) = 0.002). The median follow-up time for patients was 5.8 years. High tumor tissue levels of uPAR were associated with longer postoperative survival (HR = 0.4, 95% CI = 0.2-0.8, p = 0.01). In contrast, shorter survival was evident in patients with high tumor levels of uPA from 2 years on after operation (HR = 4.6, 95% CI = 1.2-17, p = 0.02). High tPA levels tended to be associated with shorter overall survival after 2 years (HR = 2.9, 95% 95% CI = 0.9-9.8, p = 0.08). Although high tumor tissue content of uPAR was associated with a less aggressive phenotype characterized by well differentiated histology and longer survival, low content of uPAR in the poorly differentiated tumors and metastases presumably results from increased elimination of uPAR.

Serum tetranectin is an independent prognostic marker in colorectal cancer and weakly correlated with plasma suPAR, plasma PAI-1 and serum CEA

Soluble tetranectin (TN) was measured preoperatively in serum from 567 patients with primary colorectal cancer and levels were tested for association with prognosis. The prognostic significance of TN was also compared to that of plasminogen-activator inhibitor-1 (PAI-1), urokinase plasminogen activator (uPAR) and carcinoembryonic antigen (CEA). Significantly shorter survival was found for patients with TN levels below a cut-off point of 7.5 mg/l compared to patients with levels above, as illustrated by Kaplan-Meier curves. By Cox analyses, log TN, log soluble uPAR as well as log CEA were found to have an independent prognostic value for survival (log TN: HR = 0.47, 95% CI: 0.29-0.76); log soluble uPAR: HR = 1.65, 95% CI: 1.18-2.31; log CEA: HR = 1.I1, 95% CI: 1.03-1.20). Based on the multivariate model, a patient with a combination of low levels of TN and PAI-1 and elevated levels of soluble uPAR and CEA had a 2.43 increased risk as compared to a patient with median levels of these biochemical markers. Significant correlations were found with Dukes' stages for all the biochemical markers and between the respective biochemical markers. The findings confirm that TN is a strong prognostic factor in patients with colorectal cancer. TN may be valuable as a prognostic variable in future studies evaluating new treatment strategies for colorectal cancer.