CD38 Defines a Subset of B Cells in Rainbow Trout Kidney With High IgM Secreting Capacities.

CD38 is a multifunctional molecule that functions both as a transmembrane signaling receptor and as an ectoenzyme with important roles in cell adhesion, calcium regulation and signal transduction. Within the B cell linage, CD38 is expressed in diverse murine B cell subsets, with highest levels in innate B cell subpopulations such as marginal zone (MZ) B cells or B1 cells. In humans, however, CD38 is transiently expressed on early lymphocyte precursors, is lost on mature B cells and is consistently expressed on terminally differentiated plasma cells. In the present work, we have identified two homologues of mammalian CD38 in rainbow trout (Oncorhynchus mykiss), designating them as CD38A and CD38B. Although constitutively transcribed throughout different tissues in homeostasis, both CD38A and CD38B mRNA levels were significantly up-regulated in head kidney (HK) in response to a viral infection. In this organ, after the generation of a specific monoclonal antibody (mAb) against CD38A, the presence of CD38A+ populations among IgM+ B cells and IgM- leukocytes was investigated by flow cytometry. Interestingly, the percentage of IgM+CD38A+ B cells increased in response to an in vitro stimulation with inactivated Aeromonas salmonicida. Finally, we demonstrated that HK IgM+CD38A+ B cells had an increased IgM secreting capacity than that of cells lacking CD38A on the cell surface, also showing increased transcription levels of genes associated with B cell differentiation. This study strongly suggests a role for CD38 on the B cell differentiation process in teleosts, and provides us with novel tools to discern between B cell subsets in these species.

A simplified assay for the quantification of circulating activated protein C.

Available assays for circulating levels of activated protein C (APC) are either time-consuming or difficult to use in a routine laboratory, or have a detection limit above normal levels. We have developed a simplified assay that measures both the in vivo free APC and the in vivo APC complexed to PC inhibitor (PCI). We measured APC levels, with both assays, in 339 plasma samples, 165 from patients with venous thromboembolism (VTE) and 174 from healthy individuals. The mean APC level in the 339 samples was 0.038±0.010 nM, using a previous assay that measures only the in vivo APC level, and 0.041±0.010 nM with the present new assay. The coefficient of correlation between assays was r=0.954 (P<0.001). The mean APC level in VTE patients was 0.034±0.009 nM (previous assay) and 0.037±0.009 nM (new assay), significantly lower than those in controls (P<0.001). In both groups there was a significant correlation between the levels obtained by the two assays (P<0.001). These results show that both assays are equivalent, and confirm that the APC level is lower in VTE patients than in healthy individuals. Therefore, the new simplified assay, which measures the sum of circulating free APC and APC complexed to PCI, may be used to estimate the level of circulating APC, and will allow its use in routine laboratories.

Peritoneal fluid reduces angiogenesis-related microRNA expression in cell cultures of endometrial and endometriotic tissues from women with endometriosis.

UNLABELLED: Endometriosis, defined as the presence of endometrium outside the uterus, is one of the most frequent gynecological diseases. It has been suggested that modifications of both endometrial and peritoneal factors could be implicated in this disease. Endometriosis is a multifactorial disease in which angiogenesis and proteolysis are dysregulated. MicroRNAs (miRNAs) are small non-coding RNAs that regulate the protein expression and may be the main regulators of angiogenesis. Our hypothesis is that peritoneal fluid from women with endometriosis could modify the expression of several miRNAs that regulate angiogenesis and proteolysis in the endometriosis development. The objective of this study has been to evaluate the influence of endometriotic peritoneal fluid on the expression of six miRNAs related to angiogenesis, as well as several angiogenic and proteolytic factors in endometrial and endometriotic cell cultures from women with endometriosis compared with women without endometriosis. METHODS: Endometrial and endometriotic cells were cultured and treated with endometriotic and control peritoneal fluid pools. We have studied the expression of six miRNAs (miR-16, -17-5p, -20a, -125a, -221, and -222) by RT-PCR and protein and mRNA levels of vascular endothelial growth factor-A, thrombospondin-1, urokinase plasminogen activator and plasminogen activator inhibitor-1 by ELISA and qRT-PCR respectively. RESULTS: Control and endometriotic peritoneal fluid pools induced a significant reduction of all miRNAs levels in endometrial and endometriotic cell cultures. Moreover, both peritoneal fluids induced a significant increase in VEGF-A, uPA and PAI-1 protein levels in all cell cultures without significant increase in mRNA levels. Endometrial cell cultures from patients treated with endometriotic peritoneal fluid showed lower expression of miRNAs and higher expression of VEGF-A protein levels than cultures from controls. In conclusion , this "in vitro" study indicates that peritoneal fluid from women with endometriosis modulates the expression of miRNAs that could contribute to the angiogenic and proteolytic disequilibrium observed in this disease.

microRNAs related to angiogenesis are dysregulated in endometrioid endometrial cancer.

STUDY QUESTION: Which is the role of microRNAs (miRNAs) related to several angiogenesis regulators such as VEGF-A (Vascular endothelial growth factor-A) and TSP-1 (Thrombospondin-1) in endometrial cancer? SUMMARY ANSWER: A dysregulated expression of miRNAs related to angiogenesis and an increase in the VEGF-A levels were observed in endometrial cancer in comparison with control. The different expression of miRNAs could modulate the expression of angiogenic and antiangiogenic factors, which may play an important role in the pathogenesis of endometrial cancer. WHAT IS KNOWN ALREADY: Dysregulated miRNA expression has been previously evaluated in endometrial adenocarcinoma. To the best of our knowledge, there are no studies on the relationship between angiogenic factors and miRNAs in endometrial cancer. STUDY DESIGN, SIZE, DURATION: Case-control study: 41 patients with histologically proven endometrioid endometrial cancer and 56 women without endometrial cancer. PARTICIPANTS/MATERIALS, SETTING, METHODS: RNAs isolated from tissue samples were analyzed using the GeneChip miRNA 2.0 Array platform (Affymetrix). TaqMan qRT-PCR was used to assess the expression of the selected miRNAs related to angiogenesis (miR-15b, -16, -17-5p, -20a, -21, -125a, -200b, -210, -214*, -221, -222 and -424), and VEGF-A and TSP-1 mRNAs were assessed by qRT-PCR using SYBR Green. Protein levels were quantified by ELISAs. MAIN RESULTS AND THE ROLE OF CHANCE: Compared with the miRNAs in the control endometrium, eight miRNAs (miR-15b, -17-5p, -20a, -125a, -214*, -221, -222 and -424) were significantly down-regulated and two miRNAs (miR-200b and -210) were significantly up-regulated in the cancerous endometrium. A significant increase in VEGF-A mRNA and protein expression and in TSP-1 protein levels (P <0.01) was observed in endometrial cancer. Moreover, significant inverse correlations between VEGF-A protein levels and miR-20a, -125a, -214*, -221, -222 and -424 were detected. In contrast, a positive correlation was observed between VEGF-A and miR-200b and -210. Furthermore, stage IB endometrial cancer was associated with a higher VEGF-A protein/mRNA ratio and lower miR-214*, -221 and -222 expression in comparison with stage IA. LIMITATIONS, REASONS FOR CAUTION: Future functional studies (e.g. miRNA inhibition or ectopic overexpression) in cell culture models are needed to confirm the VEGF targeting by the miRNAs found in the present study. WIDER IMPLICATIONS OF THE FINDINGS: The findings of the present study have potential implications for diagnostics and therapeutics of endometrial carcinoma. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research grants from the Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (Instituto de Salud Carlos III, Fondo de Investigación Sanitaria, PI080185, PI0110091) and Red RECAVA (RD06/0014/0004), by Consellería de Sanidad (AP-141/11) and Consellería de Educación (PROMETEO/2011/027), Generalitat Valenciana, by Beca Fibrinolisis 2009 and Becario 2010, 2011 from Fundación Española de Trombosis y Hemostasia and by the Fundación Investigación Hospital La Fe, Spain. None of the authors have any conflicts of interest.

Plasminogen activator inhibitor-1 (PAI-1) 4 G/5 G polymorphism and endometrial cancer. Influence of PAI-1 polymorphism on tissue PAI-1 antigen and mRNA expression and tumor severity.

Plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism may have significance for PAI-1 expression. High levels of PAI-1 in endometrial cancer patients are associated with a poor prognosis. The objective of this study was to evaluate the PAI-1 4G/5G polymorphism in women with and without endometrial cancer and to analyze the influence of this polymorphism on PAI-1 expression in endometrial tissue. In 423 women (212 patients with endometrial cancer and 211 controls) PAI-1 4G/5G polymorphism was determined by PCR amplification using allele-specific primers. Quantitative real-time RT-PCR assay was used to quantify PAI-1 mRNA and PAI-1 protein levels were quantified by ELISA in tissue extracts from 33 patients with endometrial cancer and from 70 endometrial tissues from control women. The frequency of PAI-1 4G/4G genotype (P=0.010) and the PAI-1 4G allele (P=0.009) was significantly higher in patients than in controls. The frequency of PAI-1 4G allele was significantly higher in patients with stage IB than in those with stage IA (P=0.03). Control women with the 4G/4G genotype had higher endometrial PAI-1 protein (P=0.018) and mRNA (P=0.004) levels than those with the 5G/5G genotype. A significant increase in PAI-1 protein and mRNA was observed in endometrial cancer tissue in comparison with the endometrial tissue from control women (P<0.01). In conclusion, frequencies of the PAI-1 4G allele and 4G/4G genotype were found significantly more often in women with endometrial cancer than in controls. PAI-1 levels in endometrial tissue seem to be associated with PAI-1 4G/5G polymorphism. These findings suggest that the PAI-1 4G/4G genotype may be associated with the risk of endometrial cancer in a Caucasian population. Further studies with a larger number of patients are needed to clarify the influence of this PAI-1 polymorphism in endometrial cancer.

microRNAs expression in endometriosis and their relation to angiogenic factors.

BACKGROUND: Endometriosis is a common, multifactorial disease in which angiogenesis may be involved in the growth of endometrium outside the uterus. microRNAs (miRNAs) are 21-22 nucleotide non-coding RNAs that regulate gene expression and play fundamental roles in biological processes. The objective of this study was to analyze several miRNAs related to angiogenesis and the angiogenic factors, vascular endothelial growth factor-A (VEGF-A) and thrombospondin-1 (TSP-1), in endometriotic lesions (ovarian endometrioma, peritoneal lesion and rectovaginal nodule) and eutopic endometrium from women with endometriosis. METHODS: TaqMan real-time PCR was used to assess the expression of the miRNAs (miR-15b, -16, -17-5p, -20a, -21, -125a, -221 and -222), while VEGF-A and TSP-1 mRNA were assessed by real-time PCR, with SYBR Green I and VEGF-A and TSP-1 protein levels were quantified by ELISA. Included in the study were 58 women with endometriosis and 38 control women. RESULTS: In paired samples, ovarian endometrioma showed significantly lower VEGF-A mRNA (P = 0.02) and protein (P = 0.002) expression than eutopic endometrium and higher expression of miR-125a (P = 0.003) and miR-222 (P <0.001). However, ovarian endometrioma had significantly higher expression of the angiogenic inhibitor TSP-1 and lower expression of miR-17-5p than eutopic endometrium (P < 0.001). Moreover, a significant inverse correlations between miR-222 and VEGF-A protein levels (-0.267, P = 0.018) and between miR-17-5p and TSP-1 protein levels (-0.260, P=0.022) were observed. Peritoneal lesions showed a significant increase in VEGF-A in comparison with ovarian endometrioma (P < 0.01). CONCLUSIONS: Expression levels of miRNAs related to angiogenesis were different in eutopic endometrium from that observed in ovarian endometrioma. This could influence the expression of angiogenic factors and play a role in the pathogenesis of endometriosis.

Vascular endothelial growth factor polymorphisms (-460C/T, +405G/C, and 936C/T) and endometriosis: their influence on vascular endothelial growth factor expression.

OBJECTIVE: To analyze three functional vascular endothelial growth factor (VEGF) polymorphisms (-460C/T, +405G/C, and 936C/T) in women with and without endometriosis and their correlation with VEGF expression in endometrial tissue and peritoneal fluid (PF). DESIGN: Case-control study. SETTING: University-based hospital. PATIENT(S): One hundred eighty-six women with endometriosis and 180 controls without the disease. INTERVENTION(S): Endometrial biopsies were performed by aspiration and PF samples were obtained at laparoscopy. MAIN OUTCOME MEASURE(S): VEGF polymorphisms (-460C/T, +405G/C, and 936C/T) were determined using a polymerase chain reaction (PCR)-restriction fragment length polymorphism assay. Quantitative real-time reverse transcriptase (RT)-PCR assay was used to quantify VEGF-A messenger RNA (mRNA) and VEGF-A antigen levels were quantified by ELISA. RESULT(S): Patients with endometriosis showed a higher VEGF 936T allele frequency than controls. However, the distribution of genotypes and allele frequencies in the other two VEGF (-460C/T, +405G/C) polymorphisms was similar in the endometriosis and control groups. Endometrium and PF from women with endometriosis showed an increase in VEGF levels, but no association was found between the VEGF polymorphisms studied and VEGF expression in endometrial tissue and PF. CONCLUSION(S): These findings suggest that the VEGF 936C/T polymorphism may be associated with the risk of endometriosis in a Caucasian population, but the increased VEGF levels observed in endometriosis do not appear to be associated with this polymorphism.

Fibrinolysis: the key to new pathogenetic mechanisms.

The fibrinolytic system includes a broad spectrum of proteolytic enzymes with physiological and pathophysiological functions in several processes, such as haemostatic balance, tissue remodeling, tumor invasion, angiogenesis and reproduction. The main enzyme of the plasminogen activator system is plasmin, which is responsible for the degradation of fibrin into soluble degradation products. The activation of plasminogen into plasmin is mediated by two types of activators, urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA). The activity of both is regulated by specific plasminogen activator inhibitors (PAIs). There are 3 types of PAIs described so far but the most important fibrinolytic inhibitor in vivo is PAI type 1 (PAI-1). Among others, the presence of metabolic syndrome and the -675 4G/5G promoter polymorphism are known to be modulators of PAI-1 levels. Besides their fibrinolytic profile, plasmin and plasminogen activators are implicated in tissue proliferation and cellular adhesion, as they can proteolytically degrade the extracellular matrix and regulate the activation of both growth factors and matrix metalloproteinases. By all these means, the fibrinolytic system is also involved in physiological processes, and in pathological situations such as thrombosis, arteriosclerosis, endometriosis and cancer. PAI 1 has been studied in different settings with thrombotic pathophysiology, such as coronary artery disease and ischaemic stroke. Controversial results have been published and concerns about study designs or presence of confounders have been claimed to be responsible of them. Recently, its involvement in adverse thrombotic events related to the modern drug-eluting coronary stents has renewed the interest of its study. PAI-1 also plays an important role in signal transduction, cell adherence, and migration. Indeed, studies of several types of cancers, including breast cancer, have shown that increased uPA and PAI-1 levels are associated with aggressive tumor behavior and poor prognosis. Endometriosis is defined by the presence of endometrial glands and stroma outside the uterus with marked ability to attach and invade the peritoneum. It is one of the most frequent benign gynecological diseases that affect women with pelvic pain or infertility during their reproductive age. Immune system disorders, genetic predisposition, altered peritoneal environment and endometrial alterations are believed to increase the susceptibility to endometriosis. The plasminogen activator system may be involved in this process, where local extracellular proteolysis plays a crucial role. Altered expression of several components of the fibrinolytic system in both eutopic and ectopic endometrium and peritoneal fluid of women with the disease has been implicated not only in the onset, but also in the progression of the endometriotic lesions.

Plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism and endometriosis. Influence of PAI-1 polymorphism on PAI-1 antigen and mRNA expression.

INTRODUCTION: Endometriosis is a benign gynecologic disease with a high prevalence. It is a multifactorial and polygenic entity in which the fibrinolytic system may be implicated. The objective of this study was to evaluate the plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism in a group of women with and without endometriosis and to analyze the influence of this polymorphism in PAI-1 expression in endometrial tissue and peritoneal fluid. MATERIAL AND METHODS: In 389 women (170 patients with endometriosis and 219 controls) PAI-1 4G/5G polymorphism was determined by PCR amplification using allele-specific primers. Quantitative real-time RT-PCR assay was used to quantify PAI-1 mRNA and PAI-1 antigen (ag) levels were quantified by ELISA. RESULTS: The genotype and allele frequencies of PAI-1 4G/5G polymorphism did not differ significantly between patients and controls. Control women with the 4G/4G genotype had higher endometrial PAI-1ag (P=0.026) and mRNA (P=0.014) levels than those with the 5G/5G genotype. Control carrying the 4G/4G genotype tended to have higher peritoneal fluid PAI-1ag levels than those carrying the 5G/5G genotype. Moreover, PAI-1ag levels in peritoneal fluid were higher in patients than in controls (P=0.003). CONCLUSIONS: The PAI-1 genotype distribution was similar in patients and controls. PAI-1 levels in endometrial tissue and peritoneal fluid seem to be associated with PAI-1 4G/5G polymorphism in controls. The increased PAI-1ag levels observed in peritoneal fluid from patients could contribute to increase the peritoneal adhesions observed in endometriosis.

Fibrinolytic inhibitor levels and polymorphisms in Behçet disease and their association with thrombosis.

This study aimed to assess the fibrinolytic inhibitors and their association with thrombosis in Behçet disease. Thrombin activatable fibrinolysis inhibitor (TAFI) (P < 0.001) and plasminogen activator inhibitor-1 (PAI-1) levels (P = 0.022) were significantly higher in 79 patients than in 84 controls. No significant differences were observed in CPB2 (TAFI) Thr325Ile and SERPINE1 (PAI1) 4G/5G polymorphism distribution between patients and controls. TAFI activity levels were significantly higher in patients with thrombosis than in those without thrombosis (P = 0.024). In conclusion, the increased TAFI levels in Behçet disease could contribute to the increased risk of thrombosis observed in these patients.

Plasminogen activator inhibitor-1 levels in severe and morbid obesity. Effect of weight loss and influence of 4G/5G polymorphism.

INTRODUCTION: An association between an increase in plasminogen activator inhibitor type 1 and obesity has been described. It has also been shown that a decrease in adiposity has beneficial effects. However, less information is available regarding morbid obesity and hypofibrinolysis. The aim of the present study was to evaluate the effect of weight loss and the influence of the plasminogen activator inhibitor type 1 promoter 4G/5G genotype on plasminogen activator inhibitor type 1 levels in severe and morbid obesity. MATERIALS AND METHODS: Sixty-seven obese patients were studied before and three months after a weight reduction program, and compared with 67 controls. We determined plasminogen activator inhibitor type 1 antigen and activity levels, tissue type plasminogen activator antigen levels, 4G/5G genotype and biochemical parameters in both groups. RESULTS: A significant increase in plasminogen activator inhibitor type 1 antigen and activity was observed in obese patients in comparison with the control group (P<0.001). No significant differences in plasminogen activator inhibitor type 1 levels among 4G/5G genotypes were obtained. After weight loss, a significant decrease in plasminogen activator inhibitor type 1 antigen and activity was observed (P<0.001). A significant and positive correlation was observed in percentage changes in plasminogen activator inhibitor type 1 and body mass index (P=0.02). CONCLUSIONS: A decrease in body mass index in severe and morbid obesity shows a favourable effect on the fibrinolytic system due to a decrease in plasminogen activator inhibitor type 1 levels. However, no influence of 4G/5G polymorphism has been observed in this setting.

Expression of plasminogen activator inhibitors type 1 and type 3 and urokinase plasminogen activator protein and mRNA in breast cancer.

BACKGROUND: The urokinase plasminogen activator (uPA) system has been involved in cancer cell invasion and in metastasis. uPA activity is controlled by its principal inhibitor, the PA inhibitor type-1 (PAI-1), but it can also be inhibited by PAI-3. Increased levels of uPA and PAI-1 are known to be associated with a poor prognosis in breast cancer. To our knowledge this is the first study of the expression and role of PAI-3 in human breast cancer tissue. MATERIALS AND METHODS: Protein and mRNA levels were evaluated for uPA, PAI-1 and PAI-3 in breast cancer tissues from 70 different patients. The localization of antigen and mRNA of these proteins was studied by immunohistochemistry and in situ hybridization, respectively. RESULTS: No significant differences were observed for PAI-3 mRNA or protein levels between the nodal status groups or the different post-surgical tumor-node-metastasis (pTNM) stages. However, uPA and PAI-1 mRNA and antigen levels significantly increased at the pTNM stage and in node-positive patients. PAI-3 antigen levels were significantly higher in early relapse-free patients, whereas PAI-1 antigen levels were significantly higher in patients who suffered a relapse. PAI-3 protein and mRNA were localized in stromal cells. PAI-1 and uPA protein were detected in cancer, endothelial and stromal cells and their mRNA mainly in stromal cells. CONCLUSIONS: Our results indicate that PAI-3 is expressed in human breast cancer tissues, and that elevated levels of PAI-3 could be a positive prognostic factor in this disease. A potential mechanism for the contribution of PAI-3 to a positive long-term outcome may involve suppression of tumor invasion through protease inhibition in stroma.

Lipoprotein (a) in young individuals as a marker of the presence of ischemic heart disease and the severity of coronary lesions.

The purpose of this study was to evaluate whether high levels and small isoforms of lipoprotein (a) [Lp(a)] are markers of risk of early myocardial infarction and markers of the severity of coronary atherosclerosis. Lp(a) levels and small apo(a) isoforms were higher in 222 patients than in 199 controls (p<0.001). In patients, Lp(a)> or =30 mg/dL was associated with the presence of coronary lesions (p=0.007) and the severity of coronary atherosclerosis (p=0.002). The present study suggests that Lp(a) levels and small isoforms are markers of early myocardial infarction and that Lp(a) levels > or =30 mg/dL are associated with severe patterns of coronary atherosclerosis.