The urokinase-type plasminogen activator system in resected non-small-cell lung cancer. Rotterdam Oncology Thoracic Study Group

Identification of PLAUR-related ceRNA and immune prognostic signature for kidney renal clear cell carcinoma

Kidney renal clear cell carcinoma (KIRC) represents one of the most fatal cancers, usually showing malignant progression and a high tumor recurrence rate. The urokinase-type plasminogen activator receptor (PLAUR) plays a critical role in the initiation and progression of several cancers, including KIRC. However, the function and mechanism of PLAUR in patients with KIRC are still unclear and require further investigation. In the present study, we first explored the expression profile and prognostic values of PLAUR in pan-cancer based on The Cancer Genome Atlas and Genotype-Tissue Expression databases. PLAUR was upregulated in multiple cancers and was significantly associated with poor overall survival and disease-free survival only in patients with KIRC. Subsequently, the PVT1/SNHG15-hsa-miR-532-3p axis was identified as the most potential upstream regulatory network of PLAUR in KIRC. In addition, PLAUR expression was closely associated with tumor-infiltrating immune cells, tumor immunity biomarkers, and immunomodulator expression. Furthermore, we constructed a multiple-gene risk prediction signature according to the PLAUR-related immunomodulators (PRIs). A prognostic nomogram was then developed to predict the 1-, 3-, and 5-year survival probabilities of individuals. In conclusion, our study identified the PVT1/SNHG15-hsa-miR-532-3p-PLAUR axis and a prognostic signature of PRIs, which could be a reference for future clinical research.

Analysis of lung cancer-related genetic changes in long-term and low-dose polyhexamethylene guanidine phosphate (PHMG-p) treated human pulmonary alveolar epithelial cells

BACKGROUND

Lung injury elicited by respiratory exposure to humidifier disinfectants (HDs) is known as HD-associated lung injury (HDLI). Current elucidation of the molecular mechanisms related to HDLI is mostly restricted to fibrotic and inflammatory lung diseases. In our previous report, we found that lung tumors were caused by intratracheal instillation of polyhexamethylene guanidine phosphate (PHMG-p) in a rat model. However, the lung cancer-related genetic changes concomitant with the development of these lung tumors have not yet been fully defined. We aimed to discover the effect of long-term exposure of PHMG-p on normal human lung alveolar cells.

METHODS

We investigated whether PHMG-p could increase distorted homeostasis of oncogenes and tumor-suppressor genes, with long-term and low-dose treatment, in human pulmonary alveolar epithelial cells (HPAEpiCs). Total RNA sequencing was performed with cells continuously treated with PHMG-p and harvested after 35 days.

RESULTS

After PHMG-p treatment, genes with transcriptional expression changes of more than 2.0-fold or less than 0.5-fold were identified. Within 10 days of exposure, 2 protein-coding and 5 non-coding genes were selected, whereas in the group treated for 27-35 days, 24 protein-coding and 5 non-coding genes were identified. Furthermore, in the long-term treatment group, 11 of the 15 upregulated genes and 9 of the 14 downregulated genes were reported as oncogenes and tumor suppressor genes in lung cancer, respectively. We also found that 10 genes of the selected 24 protein-coding genes were clinically significant in lung adenocarcinoma patients.

CONCLUSIONS

Our findings demonstrate that long-term exposure of human pulmonary normal alveolar cells to low-dose PHMG-p caused genetic changes, mainly in lung cancer-associated genes, in a time-dependent manner.

Urokinase-type plasminogen activator receptor (uPAR) as a therapeutic target in cancer

Urokinase-type plasminogen activator receptor (uPAR) is an attractive target for the treatment of cancer, because it is expressed at low levels in healthy tissues but at high levels in malignant tumours. uPAR is closely related to the invasion and metastasis of malignant tumours, plays important roles in the degradation of extracellular matrix (ECM), tumour angiogenesis, cell proliferation and apoptosis, and is associated with the multidrug resistance (MDR) of tumour cells, which has important guiding significance for the judgement of tumor malignancy and prognosis. Several uPAR-targeted antitumour therapeutic agents have been developed to suppress tumour growth, metastatic processes and drug resistance. Here, we review the recent advances in the development of uPAR-targeted antitumor therapeutic strategies, including nanoplatforms carrying therapeutic agents, photodynamic therapy (PDT)/photothermal therapy (PTT) platforms, oncolytic virotherapy, gene therapy technologies, monoclonal antibody therapy and tumour immunotherapy, to promote the translation of these therapeutic agents to clinical applications.

Explication of the roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) as diagnostic and predictor tools for prostate cancer in equivocal PSA range of 4-10 ng/mL

Background

Prostate cancer (PCa) is one of the most commonly encountered cancers and the leading cause of death worldwide. Currently used biomarkers accounts difficulties in discriminating benign from malignant cases or predicting outcome, so investigating new biomarkers performance is needed.

Objectives

Assessment of diagnostic and predictor roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) in PCa.

Methods

194 males with initial tPSA of 4-10 ng/mL were categorized into three groups: PCa, benign prostatic hyperplasia (BPH) and healthy control. Serum levels of tPSA, fPSA, p2PSA, and uPA were performed by ELISA with calculation of PHI as (p2PSA/fPSA) × √PSA.

Results

PHI and uPA were significantly higher in PCa patients relevant to BPH and healthy control (p ≤ 0.001). Both markers outperformed all assessed biomarkers and showed the highest area under the curve (AUC) in ROC curve analysis. Both were significantly higher in PCa patients with {Gleason score ≥ 7, late stages (cT2b,c; T3), LN extension and distant metastasis}relative to their counterparts. Additionally, PHI and uPA and were independent predictors of distant metastasis and Gleason score ≥ 7, while PHI was predictor of LN invasion (β = 0.25, p = 0.004).

Conclusion

PHI and uPA would be of potential value in discriminating between PCa, BPH and healthy men in addition, both are promising as independent predictors of adverse pathological features.

The urokinase-type plasminogen activator and inhibitors in resectable lung adenocarcinoma

BACKGROUND

The urokinase-type plasminogen activator (uPA) system is closely related to the occurrence and progression of cancer in many aspects. Previous studies demonstrated that the conclusions about the prognosis value of uPA, plasminogen activator inhibitor 1 (PAI-1) and plasminogen activator inhibitor 2 (PAI-2) in lung cancer are controversial, so this study was performed for the exploration of the predictive effect of uPA, PAI-1 and PAI-2 on the overall survival (OS) of resectable pulmonary adenocarcinoma patients.

METHODS

UPA, PAI-1 and PAI-2 expression levels were assayed by immunohistochemical staining based on tissue microarray (TMA) that is composed of formalin-fixed paraffin-embedded specimens from 84 resectable lung adenocarcinoma patients from July 2004 to June 2009. The relationship of IHC, mRNA expression levels of three molecules were investigated respectively. The three molecules' relationship with clinicopathologic parameters and OS was explored by Chi-square, Kaplan-Meier, and Cox regression analyses. The Cancer Genome Atlas (TCGA) database was used to analyze differential gene expressions of RNA-sequencing data of pulmonary adenocarcinoma and normal tissues, and Kaplan-Meier methods were adopted to confirm the prognostic value of uPA, PAI-1 and PAI-2 in resectable lung adenocarcinoma in TCGA database and the R package MethylMix was used to conduct an analysis integrating methylation data and gene expression of RNA-sequencing data based on TCGA.

RESULTS

UPA, PAI-1 and PAI-2 had much higher IHC expression levels in tumor than those in the normal tissues (uPA, Z = -10.511; PAI-1, Z = -4.836; PAI-2, Z = -6.794; all P < 0.0001). High DNA methylation level of gene uPA resulted in the decrease of its expression. In addition, expression level of PAI-2 was positively associated with tumor size (χ² = 8.372, P =  0.004). Multivariate analyses showed TNM stage III was an independent adverse prognostic factor (hazard ratio = 3.736, 95 % confidence interval = 1.097-12.72, P =  0.035). Kaplan-Meier method revealed that uPA, PAI-1 and PAI-2 expression levels were not related to the OS for 84 resectable lung adenocarcinoma patients. According to TCGA data, PAI-1 expression level was identified as a potential adverse predictor for prognosis of resectable lung adenocarcinoma (Gehan-Breslow-Wilcoxon test, P = 0.025).

CONCLUSIONS

Our data show that, the expression levels of uPA, PAI-1 and PAI-2 are significantly up-regulated in resectable lung adenocarcinoma. Besides, this study highlights PAI-1 as a latent adverse prognostic factor in resectable adenocarcinoma of lung.

HAI-2 as a novel inhibitor of plasmin represses lung cancer cell invasion and metastasis

Background

Dysregulation of pericellular proteolysis usually accounts for cancer cell invasion and metastasis. Isolation of a cell-surface protease system for lung cancer metastasis is an important issue for mechanistic studies and therapeutic target identification.

Methods

Immunohistochemistry of a tissue array (n = 64) and TCGA database (n = 255) were employed to assess the correlation between serine protease inhibitors (SPIs) and lung adenocarcinoma progression. The role of SPI in cell motility was examined using transwell assays. Pulldown and LC/MS/MS were performed to identify the SPI-modulated novel protease(s). A xenografted mouse model was harnessed to demonstrate the role of the SPI in lung cancer metastasis.

Results

Hepatocyte growth factor activator inhibitor-2 (HAI-2) was identified to be downregulated following lung cancer progression, which was related to poor survival and tumour invasion. We further isolated a serum-derived serine protease, plasmin, to be a novel target of HAI-2. Downregulation of HAI-2 promotes cell surface plasmin activity, EMT, and cell motility. HAI-2 can suppress plasmin-mediated activations of HGF and TGF-β1, EMT and cell invasion. In addition, downregulated HAI-2 increased metastasis of lung adenocarcinoma via upregulating plasmin activity.

Conclusion

HAI-2 functions as a novel inhibitor of plasmin to suppress lung cancer cell motility, EMT and metastasis.

Correlation of Serum Levels of Urokinase Activation Plasminogen (uPA) and Its Inhibitor (PAI-1) with Hormonal and HER-2 Status in the Early Invasive Breast Cancer

Introduction:

Breast cancer is the most common malignant tumor in women. On the list of causes of death immediately after lung cancer. It is a heterogeneous disease, considering the differences in morphological, cytogenetic, molecular, clinical and therapeutic aspects, so that the prognosis in a patient with the same histological grade and pathological status may vary.

Aim:

In this paper we wanted to identify the correlation between the assay of the serum values of uPA-PAI-1 complexes and individual prognostic-predictive parameters, primarily with the status of estrogenic (Er), progesterogenic (PgR) and Her-2 receptors („human epidermal growth factor).

Material and methods:

The study was conducted at the Clinic for General and Abdominal Surgery, University Clinical Center of Sarajevo (CCUS), from September 2016 to April 2017. The study included 66 patients, ages 18 to 75, in whom by the needle biopsy preoperatively was pathohistologically verified primary invasive breast cancer.

Results:

Two thirds of the sample were classified as invasive ductal carcinoma, similar to the percentage (68.2%) of pT2 size, and almost half in the grade G3. Lymph node status was negative in 54.5% of respondents, and positive in 31.8% of respondents. Most patients had positive estrogenic (83.3%) and progesterone receptors (62.1%). Almost 80% was Her-2 negative. The blood vessel invasion was present in 56.1%, while the neural invasion was present in less than a third of the sample (30.3%). Median values of uPA-PAI-1 complexes were 1.4 (interquartile range 0.9); almost 70% of the sample was negative for the status analysis of uPA-PAI-1 complex (<1).

Discussion:

A statistically significant difference was determined in the mean values of uPA-PAI-1 complexes in subgroups according to menopausal status, tumor size, histological grade, histological type (invasive ductal carcinoma vs. invasive lobular cancer versus invasive ductal carcinoma vs. invasive lobular cancer), status axillary lymph nodes, Ki67 status (as binary variables), invasion of the blood vessels and neural invasion, as well as subgroups according to the status of expression of hormonal (estrogen and progesterone) receptors.

Conclusion:

There is a statistically significant difference in the mean values of the uPA-PAI-1 complex and Her-2 receptor expression. Generally, in perspective, this would be the role played by the uPA/PAI-1 complex in breast cancer, which is that the elevated complex values have a negative prognosis and effect on survival, similar to the negative Her-2 receptor status. Complex uPA/PAI-1 is not a specific serum protein in breast cancer patients and cannot be taken as an individual prognostic-predictive marker for mass pre- or post treatment screening and prediction. Unfortunately, none of the biomarkers are able to independently and fully identify patients of the unknown stage of the disease with better or worse prognosis or to identify cases of more aggressive tumor behavior of the same stage for timely inclusion of adjuvant therapy and reduction of the risk of metastatic disease. The decision on treatment and prognosis should be the result of a combination of all diagnostic, therapeutic, pathohistological and molecular-genetic variables.

Delta-tocotrienol inhibits non-small-cell lung cancer cell invasion via the inhibition of NF-κB, uPA activator, and MMP-9

Background

Delta-tocotrienol (δT), an isomer of vitamin E, exhibits anticancer properties in different cancer types including non-small-cell lung cancer (NSCLC). Yet, anti-invasive effects of δT and its underlying cellular mechanism in NSCLC have not been fully explored. Matrix metalloproteinase 9 (MMP-9)-based cell migration and invasion are critical cellular mechanisms in cancer development. The current evidence indicates that MMP-9 is upregulated in most patients, and the inhibition of MMPs is involved in decreasing invasion and metastasis in NSCLC. Therefore, its suppression is a promising strategy for attenuating cell invasion and metastasis processes in NSCLC.

Purpose

The aim of this study was to evaluate the possibility of MMP-9 inhibition as the underlying mechanism behind the antimetastatic properties of δT on NSCLC cells.

Methods

The effects of δT on cell proliferation, migration, invasion, adhesion, and aggregation capabilities were investigated using different cell-based assays. An inhibitory effect of MMP-9 enzyme activity with δT was also identified using gel zymography. Using real-time PCR and Western blot analysis, a number of cellular proteins, regulatory genes, and miRNA involved in the Notch-1 and urokinase-type plasminogen activator (uPA)-mediated MMP-9 pathways were examined.

Results

The study found that δT inhibited cell proliferation, cell migration, invasion, aggregation, and adhesion in a concentration-dependent manner and reduced MMP-9 activities. Real-time PCR and Western blot analysis data revealed that δT increased miR-451 expressions and downregulated Notch-1-mediated nuclear factor-κB (NF-κB), which led to the repressed expression of MMP-9 and uPA proteins.

Conclusion

δT attenuated tumor invasion and metastasis by the repression of MMP-9/uPA via downregulation of Notch-1 and NF-κB pathways and upregulation of miR-451. The data suggest that δT may have potential therapeutic benefit against NSCLC metastasis.

Multifaceted Role of the Urokinase-Type Plasminogen Activator (uPA) and Its Receptor (uPAR): Diagnostic, Prognostic, and Therapeutic Applications

The plasminogen activator (PA) system is an extracellular proteolytic enzyme system associated with various physiological and pathophysiological processes. A large body of evidence support that among the various components of the PA system, urokinase-type plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitor-1 and -2 (PAI-1 and PAI-2) play a major role in tumor progression and metastasis. The binding of uPA with uPAR is instrumental for the activation of plasminogen to plasmin, which in turn initiates a series of proteolytic cascade to degrade the components of the extracellular matrix, and thereby, cause tumor cell migration from the primary site of origin to a distant secondary organ. The components of the PA system show altered expression patterns in several common malignancies, which have identified them as ideal diagnostic, prognostic, and therapeutic targets to reduce cancer-associated morbidity and mortality. This review summarizes the various components of the PA system and focuses on the role of uPA-uPAR in different biological processes especially in the context of malignancy. We also discuss the current state of knowledge of uPA-uPAR-targeted diagnostic and therapeutic strategies for various malignancies.

Expression Analysis of Angiogenesis-Related Genes in Bulgarian Patients with Early-Stage Non-Small Cell Lung Cancer

Aims and background

Angiogenesis is a key process in the early stages of tumor development. In this study we aimed to evaluate the expression of a panel of angiogenesis-related genes in a group of Bulgarian patients with early-stage non-small cell lung cancer (NSCLC).

Methods and study design

We analyzed the expression of 84 genes associated with the angiogenic process in 12 NSCLCs of two histological subtypes: 7 adenocarcinomas and 5 squamous cell carcinomas. Eight peripheral nontumorous tissues were used as controls. We performed real-time PCR on pathway-specific gene arrays (SABiosciences).

Results

Our pilot study identified upregulated genes in early-stage NSCLC including growth factors (TGFA and EFNA3), the adhesion molecule THBS2, cytokines and chemokines (MDK, CXCL9, CXCL10), and the serine protease PLAU. Several genes showed downregulation including one growth factor (FIGF), the receptors for growth factors TEK and S1PR1 as well as adhesion molecules (COL4A3 and CDH5), the cytokine IL6, the matrix protein LEP and the transcription factor NOTCH4. The study demonstrated deregulated genes specific for the two histological subtypes including the transcription factor HAND2, which was overexpressed in squamous cell carcinomas but not adenocarcinomas.

Conclusions

Despite the limited number of patients, our results demonstrated the potential of angiogenesis-related genes as biomarkers in the early stages of NSCLC development. Free full text available at www.tumorionline.it

Prognostic implications of the co-detection of the urokinase plasminogen activator system and osteopontin in patients with non-small-cell lung cancer undergoing radiotherapy and correlation with gross tumor volume

BACKGROUND

The urokinase plasminogen activator system (uPA, uPAR, PAI‑1) is upregulated in cancer and high plasma levels are associated with poor prognosis. Their interaction with hypoxia-related osteopontin (OPN) which is also overexpressed in malignant tumors suggests potential clinical relevance. However, the prognostic role of the uPA system in the radiotherapy (RT) of non-small-cell lung cancer (NSCLC), particularly in combination with OPN, has not been investigated so far.

METHODS

uPA, uPAR, PAI‑1 and OPN plasma levels of 81 patients with locally advanced or metastasized NSCLC were prospectively analyzed by ELISA before RT and were correlated to clinical patient/tumor data and prognosis after RT.

RESULTS

uPAR plasma levels were higher in M1; uPA and PAI‑1 levels were higher in M0 NSCLC patients. uPAR correlated with uPA (p < 0.001) which also correlated with PAI‑1 (p < 0.001). The prognostic impact of OPN plasma levels in the RT of NSCLC was previously reported by our group. PAI‑I plasma levels significantly impacted overall (OS) and progression-free survival (PFS). Low PAI‑1 levels were associated with a significantly reduced OS and PFS with a nearly 2‑fold increased risk of death (p = 0.029) and tumor progression (p = 0.029). In multivariate analysis, PAI‑1 levels remained an independent prognostic factor for OS and PFS with a 3‑fold increased risk of death (p = 0.001). If PAI‑1 plasma levels were combined with OPN or tumor volume, we found an additive prognostic impact on OS and PFS with a 2.5- to 3‑fold increased risk of death (p = 0.01).

CONCLUSION

Our results suggest that PAI-1 but not uPA and uPAR might add prognostic information in patients with advanced NSCLC undergoing RT. High pretreatment PAI-1 plasma levels were found predominantly in M0-stage patients and indicate a favorable prognosis as opposed to OPN where high plasma levels are associated with poor survival and metastasis. In combination, PAI-1 and OPN levels successfully predicted outcome and additively correlated with prognosis. These findings support the notion of an antidromic prognostic impact of OPN and PAI-1 plasma levels in the RT of advanced NSCLC.

The urokinase-type plasminogen activator system and its role in tumor progression

In the multistage process of carcinogenesis, the key link in the growth and progression of the tumor is the invasion of malignant cells into normal tissue and their distribution and the degree of destruction of tissues. The most important role in the development of these processes is played by the system of urokinase-type plasminogen activator (uPA system), which consists of several components: serine proteinase – uPA, its receptor – uPAR and its two endogenous inhibitors – PAI-1 and PAI-2. The components of the uPA system are expressed by cancer cells to a greater extent than normal tissue cells. uPA converts plasminogen into broad spectrum, polyfunctional protease plasmin, which, in addition to the regulation of fibrinolysis, can hydrolyze a number of components of the connective tissue matrix (СTM), as well as activate the zymogens of secreted matrix metalloproteinases (MMР) – pro-MMР. MMРs together can hydrolyze all the main components of the СTM, and thus play a key role in the development of invasive processes, as well as to perform regulatory functions by activating and releasing from STM a number of biologically active molecules that are involved in the regulation of the main processes of carcinogenesis. The uPA system promotes tumor progression not only through the proteolytic cascade, but also through uPAR, PAI-1 and PAI-2, which are involved in both the regulation of uPA/uPAR activity and are involved in proliferation, apoptosis, chemotaxis, adhesion, migration and activation of epithelial-mesenchymal transition pathways. All of the above processes are aimed at regulating invasion, metastasis and angiogenesis. The components of the uPA system are used as prognostic and diagnostic markers of many cancers, as well as serve as targets for anticancer therapy.

Prognostic value of urokinase plasminogen activator system in non-small cell lung cancer: A systematic review and meta-analysis

Current relevant research suggests there are significant differences between the expression of the urokinase plasminogen activator (uPA) system in cancer tissues and in normal tissues. However, the potential effectiveness of the uPA system as a prognostic biomarker of non-small cell lung cancer (NSCLC) remains unclear. In the present study, a systematic review and meta-analysis were performed to evaluate the relevance of the uPA system in the prognosis of patients with NSCLC. Using the PubMed, EMBASE, Web of Science and Cochrane Library databases, data from relevant academic journal articles were extracted and subjected to analysis. Associations between expression profiles pertaining to the uPA system and the overall survival (OS) of patients with NSCLC were analyzed. The study incorporated data from 11 independent journal articles and these reports included a total of 937 patients with NSCLC. The meta-analysis results revealed that increased expression of urokinase plasminogen activator (uPA) and PA inhibitor type 1 (PAI-1) exhibited no significant association with poor OS [hazard ratio (HR)-uPA=1.07 (0.87-1.31), P=0.53; HR-PAI-1=1.02 (0.63-1.65), P=0.94]. Similarly, reduced expression of PAI type 2 (PAI-2) did not significantly correlate with poor OS [HR-PAI-2=1.58 (0.64-3.90); P=0.32]. Notably, however, a significant association was observed between increased expression levels of uPA receptor (uPAR) and poor OS for NSCLC [HR-uPAR=1.50 (1.04-2.15); P=0.03]. Therefore, the expression of uPAR in the uPA system of patients with NSCLC could be used as a novel clinical biomarker to evaluate the prognosis of NSCLC. The utilization of this biomarker may provide a platform for the further development of targeted drugs for the treatment of NSCLC.

Low expression of SerpinB2 is associated with reduced survival in lung adenocarcinomas

Lung cancer is a leading cause of cancer deaths worldwide and new biomarkers are of utmost importance. Studies have indicated that the anti-plasminogen activators SerpinB2 and Neuroserpin, and the adhesion molecule L1CAM, have a coordinated impact on development of metastasis. Here, we examined whether expression of these markers was associated with clinico-pathologic characteristics and prognosis in resected non-small cell lung cancer (NSCLC).

Surgical specimens from 438 NSCLC patients treated at Haukeland University Hospital, Bergen, Norway (1993-2010) were included (median age 68 years; 213 adenocarcinomas, 135 squamous cell carcinomas, 90 others). Representative tumor sections were stained for SerpinB2, Neuroserpin, and L1CAM.

Low expression of SerpinB2 was associated with reduced lung cancer specific survival (LCSS) in adenocarcinomas (p = 0.017), also in stage I (p = 0.031). In contrast, high SerpinB2 was associated with reduced LCSS in stage I squamous cell carcinomas (p = 0.022). Although Neuroserpin and L1CAM showed some associations with clinico-pathologic phenotype, there were no associations with survival. In multivariate survival analysis of adenocarcinomas, low SerpinB2 demonstrated independent prognostic value (HR 1.8, p = 0.008).

In summary, low expression of SerpinB2 in lung adenocarcinomas was an independent prognostic factor. In contrast to findings by others, we found no impact of L1CAM on survival. Introduction

Plasminogen Activator Inhibitor-2 Plays a Leading Prognostic Role among Protease Families in Non-Small Cell Lung Cancer

Background

In lung cancer, uPA, its receptor (uPAR), and the inhibitors PAI-1 and PAI-2 of the plasminogen activator family interact with MMP-2 and MMP-9 of the MMP family to promote cancer progression. However, it remains undetermined which of these markers plays the most important role and may be the most useful indicator to stratify the patients by risk.

Methods

We determined the individual prognostic value of these 6 markers by analyzing a derivation cohort with 98 non-small cell lung cancer patients by immunohistochemical staining. The correlation between the IHC expression levels of these markers and disease prognosis was investigated, and an immunohistochemical panel for prognostic prediction was subsequently generated through prognostic model analysis. The value of the immunohistochemical panel was then verified by a validation cohort with 91 lung cancer patients.

Results

In derivation cohort, PAI-2 is the most powerful prognostic factor (HR = 2.30; P = 0.001), followed by MMP-9 (HR = 2.09; P = 0.019) according to multivariate analysis. When combining PAI-2 and MMP-9, the most unfavorable prognostic group (low PAI-2 and high MMP-9 IHC expression levels) showed a 6.40-fold increased risk of a poor prognosis compared to the most favorable prognostic group (high PAI-2 and low MMP-9 IHC expression levels). PAI-2 and MMP-9 IHC panel could more precisely identify high risk patients in both derivation and validation cohort.

Conclusions

We revealed PAI-2 as the most powerful prognostic marker among PA and MMP protease family even after considering their close relationships with each other. By utilizing a combination of PAI-2 and MMP-9, more precise prognostic information than merely using pathological stage alone can be obtained for lung cancer patients.

Plasminogen activator inhibitor-1 and susceptibility to lung cancer: a population genetics perspective

AIM

The aim of this study was to investigate the polymorphism frequency of plasminogen activator inhibitor-1 (PAI-1) (rs1799889) 4G/5G in patients with lung cancer.

METHODS

In this study, 286 genomic DNAs (154 lung cancer patients+132 subjects without lung cancer) were analyzed. Polymorphisms were determined by using the polymerase chain reaction (PCR) method, with 4G and 5G allele-specific primers. PCR products were assessed by a charge-coupled device camera and exposed to 2% agarose gel electrophoresis.

RESULTS

The frequencies of the PAI-1 gene 4G/5G genotypes were found to be 21% 4G/4G, 16% 4G/5G, and 62% 5G/5G in the control group and 31.4% 4G/4G, 30.8% 4G/5G, and 37.8% 5G/5G in the patient group. It was determined that the 5G/5G genotype frequency was high in patients in comparison with other genotypes.

CONCLUSIONS

This study found a statistically significant difference between the groups with respect to genotype distribution. Consequently, we can say that the PAI-1 gene 4G/5G polymorphism is associated with lung cancer in Turkey.

Involvement of urokinase-type plasminogen activator system in cancer: an overview

Currently, there are several studies supporting the role of urokinase-type plasminogen activator (uPA) system in cancer. The association of uPA to its receptor triggers the conversion of plasminogen into plasmin. This process is regulated by the uPA inhibitors (PAI-1 and PAI-2). Plasmin promotes degradation of basement membrane and extracellular matrix (ECM) components as well as activation of ECM latent matrix metalloproteases. Degradation and remodeling of the surrounding tissues is crucial in the early steps of tumor progression by facilitating expansion of the tumor mass, release of tumor growth factors, activation of cytokines as well as induction of tumor cell proliferation, migration, and invasion. Hence, many tumors showed a correlation between uPA system component levels and tumor aggressiveness and survival. Therefore, this review summarizes the structure of the uPA system, its contribution to cancer progression, and the clinical relevance of uPA family members in cancer diagnosis. In addition, the review evaluates the significance of uPA system in the development of cancer-targeted therapies.

uPAR-targeted optical imaging contrasts as theranostic agents for tumor margin detection

Complete removal of tumors by surgery is the most important prognostic factor for cancer patients with the early stage cancers. The ability to identify invasive tumor edges of the primary tumor, locally invaded small tumor lesions, and drug resistant residual tumors following neoadjuvant therapy during surgery should significantly reduce the incidence of local tumor recurrence and improve survival of cancer patients. In this study, we report that urokinase plasminogen activator (uPA) and its receptor (uPAR) are the ligand/cell surface target pair for the development of targeted optical imaging probes for enhancing imaging contrasts in the tumor border. Recombinant peptides of the amino terminal fragment (ATF) of the receptor binding domain of uPA were labeled with near infrared fluorescence (NIR) dye molecules either as peptide-imaging or peptide-conjugated nanoparticle imaging probes. Systemic delivery of the uPAR-targeted imaging probes in mice bearing orthotopic human breast or pancreatic tumor xenografts or mouse mammary tumors led to the accumulation of the probes in the tumor and stromal cells, resulting in strong signals for optical imaging of tumors and identification of tumor margins. Histological analysis showed that a high level of uPAR-targeted nanoparticles was present in the tumor edge or active tumor stroma immediately adjacent to the tumor cells. Furthermore, following targeted therapy using uPAR-targeted theranostic nanoparticles, residual tumors were detectable by optical imaging through the imaging contrasts produced by NIR-dye-labeled theranostic nanoparticles in drug resistant tumor cells. Therefore, results of our study support the potential of the development of uPAR-targeted imaging and theranostic agents for image-guided surgery.

Plasminogen Activator Inhibitor Type 1 (PAI-1) A15T Gene Polymorphism Is Associated with Prognosis in Patients with EGFR Mutation Positive Pulmonary Adenocarcinoma

Background

Plasminogen activator inhibitor type 1 (PAI-1), an important regulator of plasminogen activator system which controls degradation of extracellular membrane and progression of tumor cells, and PAI-1 gene polymorphic variants have been known as the prognostic biomarkers of non-small cell lung cancer patients. Recently, experimental in vitro study revealed that transforming growth factor-β1 initiated PAI-1 transcription through epithelial growth factor receptor (EGFR) signaling pathway. However, there is little clinical evidence on the association between PAI-1 A15T gene polymorphism and prognosis of Korean population with pulmonary adenocarcinoma and the influence of activating mutation of EGFR kinase domain.

Methods

We retrospectively reviewed the medical records of 171 patients who were diagnosed with pulmonary adenocarcinoma and undergone EGFR mutation analysis from 1995 through 2009.

Results

In all patients with pulmonary adenocarcinoma, there was no significant association between PAI-1 A15T polymorphic variants and prognosis for overall survival. However, further subgroup analysis showed that the group with AG/AA genotype had a shorter 3-year survival time than the group with GG genotype in patients with EGFR mutant-type pulmonary adenocarcinoma (mean survival time, 24.9 months vs. 32.5 months, respectively; p=0.015). In multivariate analysis of 3-year survival for patients with pulmonary adenocarcinoma harboring mutant-type EGFR, the AG/AA genotype carriers had poorer prognosis than the GG genotype carriers (hazard ratio, 7.729; 95% confidence interval, 1.414-42.250; p=0.018).

Conclusion

According to our study of Korean population with pulmonary adenocarcinoma, AG/AA genotype of PAI-1 A15T would be a significant predictor of poor short-term survival in patients with pulmonary adenocarcinoma harboring mutant-type EGFR.

Urokinase plasminogen activator and its inhibitor type-1 as prognostic factors in differentiated thyroid carcinoma patients

OBJECTIVE

To investigate the prognostic value of urokinase-type plasminogen activator (uPA) and its inhibitor, type-1 plasminogen activator inhibitor (PAI-1), in differentiated thyroid cancer.

STUDY DESIGN

Prospective cohort study.

SETTING

University hospital.

SUBJECTS AND METHODS

Cytosolic concentrations of uPA and PAI-1 were determined in 105 patients with differentiated thyroid carcinoma and normal matched tissues using an enzyme-linked immunoassay (ELISA).

RESULTS

Both uPA and PAI-1 concentrations were significantly higher in differentiated thyroid tumors (uPA = 0.509 ± 0.767 and PAI-1 = 6.337 ± 6.415 ng/mg) compared to normal tissues (uPA = 0.237 ± 0.051, P < .001; PAI-1 = 2.368 ± 0.418 ng/mg, P < .001). uPA and PAI-1 were significantly higher if extrathyroidal invasion (uPA, P = .015; PAI-1, P < .001) or distant metastasis (PAI-1 P < .001) was present, as well as in tumors whose size exceeded 1 cm in diameter (uPA, P = .002; PAI-1, P = .001). Survival analysis revealed the significant impact of both uPA and PAI-1 on progression-free survival (PFS) (82.22 vs 49.478 months for patients with low and high uPA, respectively, P < .001; 87.068 vs 44.964 months for patients with low and high PAI-1, respectively, P < .001). Univariate analysis showed that gender, tumor size, tumor grade, extrathyroid invasion, local lymph node involvement, distant metastasis, uPA, and PAI-1 were significant predictors of PFS. However, multivariate analysis identified only distant metastasis and tumor tissue uPA and PAI-1 as independent prognostic factors.

CONCLUSION

These findings indicate that high uPA and PAI-1 levels represent independent unfavorable prognostic factors in patients with differentiated thyroid carcinoma.

Protein signature of lung cancer tissues

Lung cancer remains the most common cause of cancer-related mortality. We applied a highly multiplexed proteomic technology (SOMAscan) to compare protein expression signatures of non small-cell lung cancer (NSCLC) tissues with healthy adjacent and distant tissues from surgical resections. In this first report of SOMAscan applied to tissues, we highlight 36 proteins that exhibit the largest expression differences between matched tumor and non-tumor tissues. The concentrations of twenty proteins increased and sixteen decreased in tumor tissue, thirteen of which are novel for NSCLC. NSCLC tissue biomarkers identified here overlap with a core set identified in a large serum-based NSCLC study with SOMAscan. We show that large-scale comparative analysis of protein expression can be used to develop novel histochemical probes. As expected, relative differences in protein expression are greater in tissues than in serum. The combined results from tissue and serum present the most extensive view to date of the complex changes in NSCLC protein expression and provide important implications for diagnosis and treatment.

Clinical utility of level-of-evidence-1 disease forecast cancer biomarkers uPA and its inhibitor PAI-1

The prognostic and/or predictive value of the cancer biomarkers, urokinase-type plasminogen activator (uPA) and its inhibitor (plasminogen activator inhibitor [PAI]-1), determined by ELISA in tumor-tissue extracts, was demonstrated for several cancer types in numerous clinically relevant retrospective or prospective studies, including a multicenter breast cancer therapy trial (Chemo-N0). Consequently, for the first time ever for any cancer biomarker for breast cancer, uPA and PAI-1 have reached the highest level of evidence, level-of-evidence-1. At present, two other breast cancer therapy trials, NNBC-3 and Plan B, also incorporating uPA and PAI-1 as treatment-assignment tools are in effect. Furthermore, small synthetic molecules targeting uPA are currently in Phase II clinical trials in patients afflicted with advanced cancer of the ovary, breast or pancreas.

Detection of cathepsin B, cathepsin L, cystatin C, urokinase plasminogen activator and urokinase plasminogen activator receptor in the sera of lung cancer patients

The present study aimed to determine the levels of cathepsin B (cath B), cathepsin L (cath L), cystatin C, urokinase plasminogen activator (u-PA) and urokinase plasminogen activator receptor (u-PAR) in the sera of patients with lung cancer compared to healthy controls using ELISA. Concomitantly, the relationship between the components and clinicopathological prognosis was analyzed. The study included 30 healthy volunteers and 105 lung cancer patients. Blood samples were collected and cath B, cath L, cystatin C, u-PA and u-PAR measurements were made using ELISA. Results showed that the levels of cath B, cath L, cystatin C, u-PA and u-PAR were significantly higher in the patient group compared to the healthy controls. The significance was marked for cath B and mild for u-PAR in correlation with lymph node metastasis. There was no significance for other parameters. Notably, patients with a combination of high cystatin C and high cath B levels had significantly lower survival probability as compared to those with cystatin C(+)/cath B(-) or with cystatin C(-)/cath B(-). Similarly, patients with a combination of high u-PA and u-PAR experienced significantly shorter survival. Furthermore, the univariate analysis revealed that cath B, u-PAR, lymph node metastases, stage and grade were related to survival. However, findings of the multivariate Cox analysis indicated that the sera levels of cath B, u-PAR and lymph node metastases may serve as independent prognostic variables in patients with lung cancer.

Quantitative secretome analysis reveals that COL6A1 is a metastasis-associated protein using stacking gel-aided purification combined with iTRAQ labeling

In cancer metastasis, secreted proteins play an important role in promoting cancer cell migration and invasion and thus also in the increase of cancer metastasis in the extracellular microenvironment. In this study, we developed a strategy that combined a simple gel-aided protein purification with iTRAQ labeling to quantify and discover the metastasis-associated proteins in the lung cancer cell secretome. Secreted proteins associated with lung cancer metastasis were produced using CL1-0 and CL1-5 cells with different metastatic abilities. Quantitative secretomics analysis identified a total of 353 proteins, 7 of which were considered to be metastasis-associated proteins. These included TIMP1, COL6A1, uPA, and AAT, all of which were higher in CL1-5, and AL1A1, PRDX1, and NID1, which were higher in CL1-0. Six of these metastasis-associated proteins were validated with Western blot analysis. In addition, pathway analysis was performed in building the interaction network between the identified metastasis-associated proteins. Further functional analysis of COL6A1 on the metastatic abilities of CL1 cells was also carried out. An RNA interference-based knock-down of COL6A1 suppressed the metastatic ability of CL1-5 cells; in contrast, a plasmid-transfected overexpression of COL6A1 increased the metastatic ability of CL1-0 cells. This study describes a simple and high throughput sample purification method that can be used for the quantitative secretomics analysis of metastasis-associated proteins.

Prognostic significance of urokinase plasminogen activator receptor and its cleaved forms in blood from patients with non-small cell lung cancer

Urokinase plasminogen activator (uPA) cleaves its three-domain cell surface receptor, uPAR, liberating domain I [uPAR(I)] and leaving the cleaved uPAR(II-III) on the cell surface. Both intact and cleaved uPAR can be shed from the cell surface. uPAR(I) was previously shown to be a prognostic factor in lung tumour extracts. Here we analyse uPAR forms in blood from patients with non-small cell lung cancer (NSCLC). Preoperatively sampled plasma/serum from 32 patients with NSCLC was analysed. Three time-resolved fluoroimmunoassays (TR-FIAs) measuring intact uPAR(I-III) (TR-FIA 1), uPAR(I-III) + uPAR(II-III) (TR-FIA 2) and uPAR(I) (TR-FIA 3) were applied. The Spearman rank correlations between plasma and serum levels of uPAR(I-III), uPAR(I-III) + uPAR(II-III), and uPAR(I) were 0.89, 0.94 and 0.68 respectively. Survival analysis demonstrated that high levels of all uPAR forms were associated with shorter survival. Adjusted for histological subtype high plasma uPAR(I-III) and uPAR(I) levels as well as serum uPAR(I) levels were significantly associated with shorter OS (hazards ratios = 4.3, 2.8 and 3.8 respectively). High blood levels of intact uPAR and its cleaved forms are associated with poor prognosis in NSCLC.

Revisiting the biological roles of PAI2 (SERPINB2) in cancer

Tumour expression of the urokinase plasminogen activator correlates with invasive capacity. Consequently, inhibition of this serine protease by physiological inhibitors should decrease invasion and metastasis. However, of the two main urokinase inhibitors, high tumour levels of the type 1 inhibitor actually promote tumour progression, whereas high levels of the type 2 inhibitor decrease tumour growth and metastasis. We propose that the basis of this apparently paradoxical action of two similar serine protease inhibitors lies in key structural differences controlling interactions with components of the extracellular matrix and endocytosis-signalling co-receptors.

High expression of plasminogen activator inhibitor-2 (PAI-2) is a predictor of improved survival in patients with pancreatic adenocarcinoma

OBJECTIVE

Recent findings suggest that the urokinase-type plasminogen activator (uPA), its receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), and -2 (PAI-2) play key roles in cancer invasion. The prognostic value of components of this system is well established in breast cancer. However, little is known of its involvement in pancreatic cancer (PC).

METHODS

Quantitative real-time polymerase chain reaction (Q-RT-PCR) was used on tissue-banked specimens and immunohistochemistry (IHC) on paraffin specimens was used to measure expression of uPA, uPAR, PAI-1, and PAI-2 proteins in 46 PC and 12 cystadenoma specimens. Results were related to survival using Cox's proportional hazards testing.

RESULTS

Increased expression of uPA, uPAR, and PAI-1 in PC tissue were independently associated with a higher Union Internationale Contre le Cancer [International Union Against Cancer (UICC)] tumor stage (P < 0.001) and were intercorrelated (P < 0.001). Overexpression of uPAR indicated reduced survival (P = 0.03). Conversely, PAI-2 messenger ribonucleic acid (mRNA) overexpression, which occurred in 21 of 46 tumors, negatively correlated with tumor size (P = 0.008) and survival (P < 0.007) but not with uPA, uPAR, or tumor stage. There was good agreement between PAI-2 mRNA value and IHC score (P < 0.001). Using Cox's stepwise analysis, PAI-2 mRNA value (HR = 0.24; P = 0.001) and UICC tumor stage (HR = 2.014; P = 0.001) independently predicted survival. An IHC score for PAI-2 of 3+ or 4+ also independently predicted improved survival (HR = 2.72; P = 0.025).

CONCLUSIONS

The uPA/uPAR/PAI-1 system is activated in advanced pancreatic cancer and may account for the tumor's aggressive behavior, whereas PAI-2 expression appears to be independent of uPA/uPAR/PAI-1 and is associated with improved prognosis. Because of its intercorrelation with mRNA expression, PAI-2 IHC may be used as an indicator of survival.

Urokinase plasminogen activator and plasminogen activator inhibitor type-1 in nonsmall-cell lung cancer: relation to prognosis and angiogenesis

BACKGROUND

Urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1) have previously been suggested as prognostic markers in nonsmall-cell lung carcinomas (NSCLC). We investigate whether uPA and PAI-1 are prognostic markers in NSCLC and whether they are related to angiogenesis.

MATERIALS AND METHODS

Frozen tumour tissue from surgical specimens from 118 previously untreated patients diagnosed with NSCLC in the period 1984-1991 were investigated. All patients were treated with surgery, and no chemo- or radiotherapy was given. UPA and PAI-1 levels were assessed using a sandwich ELISA method.

RESULTS

Both uPA and PAI-1 were independent of classical histopathological parameters as well as of microvessel density and vascular pattern. Using death within the first 5 years as endpoint, neither of the factors were prognostic markers in univariate analysis, however, significantly higher levels of uPA and PAI-1 were seen in tumours with an angiogenic vascular pattern. In multivariate analysis, high disease stage (P<0.0001), adenocarcinoma (P=0.007), old age (P=0.02), and presence of an angiogenic pattern (P=0.05) were identified as independent markers of death within 5 years.

CONCLUSIONS

The present study investigated the prognostic role of the protein levels of uPA and PAI-1 in 118 tumour specimens from patients diagnosed with NSCLC. Neither of the factors were identified as prognostic markers when evaluated with survival as endpoint. However, in tumours previously identified as non-angiogenic we found significantly lower contents of both uPA and PAI-1 as compared to angiogenic tumours, thus we hypothesize that uPA and PAI-1 stimulate angiogenesis in NSCLC.

Identification of degradome components associated with prostate cancer progression by expression analysis of human prostatic tissues

Extracellular proteases of the matrix metalloproteinase (MMP) and serine protease families participate in many aspects of tumour growth and metastasis. Using quantitative real-time RT–PCR analysis, we have undertaken a comprehensive survey of the expression of these enzymes and of their natural inhibitors in 44 cases of human prostate cancer and 23 benign prostate specimens. We found increased expression of MMP10, 15, 24, 25 and 26, urokinase plasminogen activator-receptor (uPAR) and plasminogen activator inhibitor-1 (PAI1), and the newly characterised serine proteases hepsin and matriptase-1 (MTSP1) in malignant tissue compared to benign prostate tissue. In contrast, there was significantly decreased expression of MMP2 and MMP23, maspin, and the protease inhibitors tissue inhibitor of metalloproteinase 3 (TIMP3), TIMP4 and RECK (reversion-inducing cysteine-rich protein with Kazal motifs) in the cancer specimens. The expression of MMP15 and MMP26 correlated positively with Gleason score, whereas TIMP3, TIMP4 and RECK expression correlated negatively with Gleason score. The cellular localisation of the expression of the deregulated genes was evaluated using primary malignant epithelial and stromal cell cultures derived from radical prostatectomy specimens. MMP10 and 25, hepsin, MTSP1 and maspin showed predominantly epithelial expression, whereas TIMP 3 and 4, RECK, MMP2 and 23, uPAR and PAI1 were produced primarily by stromal cells. These data provide the first comprehensive and quantitative analysis of the expression and localisation of MMPs and their inhibitors in human prostate cancer, leading to the identification of several genes involved in proteolysis as potential prognostic indicators, in particular hepsin, MTSP1, MMP26, PAI1, uPAR, MMP15, TIMP3, TIMP4, maspin and RECK.

Clinical significance of urokinase-type plasminogen activator receptor (uPAR) expression in cancer

The involvement of the urokinase-type plasminogen activator (uPA) system in particular has been extensively studied in the pathogenesis of cancer. The molecular role of the uPA receptor (uPAR) is well characterized with its participation in cell migration and extracellular matrix (ECM) degradation. Over-expression of uPAR in cancer has been demonstrated in many studies and is considered an attractive target for anticancer agents. We and others have down-regulated uPAR expression in an attempt to inhibit cancer metastasis based on its molecular role. Uniquely, uPAR which is a glycosyl phosphatidylinositol anchored protein is not only bound to the cell surface but also has a soluble form, suPAR. There is now accumulated clinical and experimental evidence supporting the significant role of uPAR and its soluble counterpart in a number of solid cancers. The expression of uPAR can be associated with tumor cells or stromal cells or both. Differences observed in the expression of uPAR using immunohistochemistry (IHC) are likely explained by the use of different antibodies and techniques rather than true cellular differences and are reviewed here. This review summarizes the clinical relevance of uPAR and its soluble form in the prognosis and diagnosis of different cancers.

Demethylation of Urokinase Promoter as a Prognostic Marker in Patients with Breast Carcinoma

PURPOSE

Urokinase (uPA) is expressed in a number of highly invasive malignancies including breast cancer. Because production of uPA is associated with breast cancer progression and can serve as a useful prognostic marker, the purpose of this study was to examine the role of uPA promoter methylation as an indicator of uPA production in breast cancer patients.

EXPERIMENTAL DESIGN

We examined the methylation status of the uPA promoter and the levels of uPA expression in normal human breast epithelial cells and several human breast cancer cells by bisulfite sequencing analysis and reverse transcription-PCR. We also analyzed the methylation status of the uPA promoter in surgical biopsy samples from patients with breast cancer of different grades, as determined by the Elston-Ellis histological grading system.

RESULTS

Expression of uPA mRNA was only detected in the highly invasive estrogen receptor-negative breast cancer cell lines, where the promoter was completely demethylated. In normal and low invasive breast cancer cells, the uPA promoter was methylated, resulting in lack of uPA mRNA expression. Analysis of biopsy samples showed that demethylation of the uPA promoter is associated with malignant transformation. Reverse transcription-PCR analysis revealed that this demethylation of the uPA promoter is directly associated with induction of uPA mRNA expression, which is well known to be associated with poor prognosis in breast cancer patients.

CONCLUSIONS

This study indicated that uPA expression in breast cancer patients is under epigenetic control via methylation of its promoter. Determination of uPA promoter methylation can therefore serve as an early reliable indicator of uPA production in breast cancer patients.

Pretreatment determination of the serum urokinase plasminogen activator and its soluble receptor in advanced small-cell lung cancer or non-small-cell lung cancer

This study was undertaken to evaluate the circulating urokinase plasminogen activator (uPA), and its soluble receptor (suPAR) in patients with either small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC). Thirty-one male and female patients with stage III or IV NSCLC and 17 with stage III or IV SCLC were compared to 138 age-matched non-smoking controls of both sexes. Before any treatment was undertaken, serum was obtained and evaluated for its content of uPA and suPAR with enzyme-linked immunosorbent assay. The results indicated a wide variation in serum uPA content that was not significant, while extremely significant increases in suPAR were found. The natural physiologic relationship between uPA and its receptor was lost in both SCLC and NSCLC, which could indicate abnormal alterations of uPA suPAR, suggesting these factors aid in the process of invasion and metastasis of lung cancer.

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.

Overexpression of a set of genes, including WISP-1, common to pulmonary metastases of both mouse D122 Lewis lung carcinoma and B16-F10.9 melanoma cell lines

Despite advances in the management of solid tumours, the development of metastases continues to be the most significant problem and cause of death for cancer patients. To define genetic determinants of pulmonary metastases, we have applied oligonucleotide microarrays to established murine models of highly metastatic D122 Lewis lung carcinoma and B16-F10.9 melanoma cell lines. These models are characterised by primary subcutaneous growth in C57BL/6J mice, a period of minimal residual disease and spontaneous pulmonary metastases. Microarray analysis defined seven genes, namely - arginase, brain natriuretic peptide (BNP), interleukin-1 alpha (IL-1 alpha), plasminogen activator inhibitor-2 (PAI-2), surfactant protein C (SP-C), uteroglobin (UG) and wnt-1-induced secreted protein-1 (WISP-1), which were consistently elevated in pulmonary metastases compared to the primary tumour of both D122 and B16-F10.9 models. Previous studies demonstrated that two of these seven genes, IL-1 alpha and PAI-2, are involved in the metastatic process. The results obtained by the microarrays were confirmed by real-time quantitative PCR, for three chosen genes - PAI-2, WISP-1 and UG. Our approach aimed to identify genes essential for the metastatic process in general and for pulmonary metastases specifically. Further research should address the precise role of these genes in the metastasising process to the lungs and test if they could be used as targets for future therapies.

[Usefulness of cytosolic tissue-type plasminogen activator levels in lung adenocarcinomas]

BACKGROUND

We aimed at studying the behavior of cytosol tissue-type plasminogen activator (t-PA) levels in lung adenocarcinomas and their correlation with other clinical and biological parameters.

MATERIAL AND METHOD

t-PA cytosol levels were determined using EIA (Boehringer Mannheim. Germany) in 59 samples of lung adenocarcinoma and in 16 samples of normal lung tissue from the same patients. Cathepsin D, CA125, pS2, hyaluronic acid (HA), free beta subunit of chorionic gonadotropin hormone and neuron specific enolase (NSE) cytosol concentrations were determined. We also determined the concentrations of HA, erbB2 oncoprotein, epidermal growth factor receptor (EGFR), CD44s, CD44v5 and CD44v6 in cell surfaces. The following parameters were considered: clinical stage, ploidy, cellular S-phase fraction and histological grade.

RESULTS

In adenocarcinomas, t-PA cytosol levels ranged from 0.1 to 14.6 ng/mg prot. (median, 1.4). These levels were lower than those in normal lung tissue (r, 0.1-18.6; median, 2.95 ng/mg prot.) but did not reach statistical significance. On the other hand, t-PA concentrations decreased as the clinical stage increased and were higher in stage I than stage II-III (p = 0.080) and stage III (p = 0.0622). No significant differences of t-PA levels were observed when the histological grade, ploidy and S-phase were considered. Adenocarcinomas with high t-PA values (> 3.7 ng/mg prot., representing the 75th percentile of the whole group), had lower CA125 (p = 0.015) and erbB2 oncoprotein (p = 0.087) concentrations.

CONCLUSIONS

These results suggest that cytosol t-PA levels are negatively correlated with tumor size in lung adenocarcinomas. However, the usefulness of t-PA as a prognostic factor needs to be clarified in further studies.

Predicting the sites of metastases from lung cancer using molecular biologic markers

BACKGROUND

The use of molecular markers in staging non-small cell lung cancer (NSCLC) has been supported in retrospective prognostic models but has not been evaluated in predicting sites of metastases.

METHODS

Pathologic specimens were collected from 202 patients after complete resection for stage I NSCLC, who were subsequently found to have no metastases at 5 years (n = 108), isolated brain metastases (n = 25), or other distant metastases (n = 69). A panel of eight molecular markers of metastatic potential was chosen for immunohistochemical analysis of the tumor: p53, erbB2, angiogenesis factor viii, EphA2, E-cadherin, urokinase plasminogen activator (UPA), UPA receptor, and plasminogen activator inhibitor.

RESULTS

Patients with isolated brain relapse had significantly higher expression of p53 (p = 0.02) and UPA (p = 0.002). The quantitative expression of E-cadherin was used to predict the site of metastases using recursive partitioning: 0 of 92 patients with E-cadherin expression of 0, 1, or 2 developed isolated cerebral metastases; 0 of 33 patients with E-cadherin expression of 3 with UPA of 1 or 2 and ErbB2 of 0 developed brain metastases. Of the remaining patients at risk (UPA = 3), the risk of isolated cerebral metastases was 21 of 57 patients (37%).

CONCLUSIONS

This study demonstrates that molecular markers may predict the site of relapse in early stage NSCLC. If validated in an ongoing prospective study, these results could be used to select patients with isolated brain metastases for adjuvant therapy, such as prophylactic cranial irradiation.