Changes in composition and sulfation patterns of glycoaminoglycans in renal cell carcinoma

The role of hyaluronan in renal cell carcinoma

Renal cell carcinoma (RCC) is associated with high mortality rates worldwide and survival among RCC patients has not improved significantly in the past few years. A better understanding of the pathogenesis of RCC can enable the development of more effective therapeutic strategies against RCC. Hyaluronan (HA) is a glycosaminoglycan located in the extracellular matrix (ECM) that has several roles in biology, medicine, and physiological processes, such as tissue homeostasis and angiogenesis. Dysregulated HA and its receptors play important roles in fundamental cellular and molecular biology processes such as cell signaling, immune modulation, tumor progression and angiogenesis. There is emerging evidence that alterations in the production of HA regulate RCC development, thereby acting as important biomarkers as well as specific therapeutic targets. Therefore, targeting HA or combining it with other therapies are promising therapeutic strategies. In this Review, we summarize the available data on the role of abnormal regulation of HA and speculate on its potential as a therapeutic target against RCC.

Plasma and Urine Free Glycosaminoglycans as Monitoring and Predictive Biomarkers in Metastatic Renal Cell Carcinoma: A Prospective Cohort Study

PURPOSE

No liquid biomarkers are approved in metastatic renal cell carcinoma (mRCC) despite the need to predict and monitor response noninvasively to tailor treatment choices. Urine and plasma free glycosaminoglycan profiles (GAGomes) are promising metabolic biomarkers in mRCC. The objective of this study was to explore if GAGomes could predict and monitor response in mRCC.

PATIENTS AND METHODS

We enrolled a single-center prospective cohort of patients with mRCC elected for first-line therapy (ClinicalTrials.gov identifier: NCT02732665) plus three retrospective cohorts (ClinicalTrials.gov identifiers: NCT00715442 and NCT00126594) for external validation. Response was dichotomized as progressive disease (PD) versus non-PD every 8-12 weeks. GAGomes were measured at treatment start, after 6-8 weeks, and every third month in a blinded laboratory. We correlated GAGomes with response and developed scores to classify PD versus non-PD, which were used to predict response at treatment start or after 6-8 weeks.

RESULTS

Fifty patients with mRCC were prospectively included, and all received tyrosine kinase inhibitors (TKIs). PD correlated with alterations in 40% of GAGome features. We developed plasma, urine, and combined glycosaminoglycan progression scores that monitored PD at each response evaluation visit with the area under the receiving operating characteristic curve (AUC) of 0.93, 0.97, and 0.98, respectively. For internal validation, the scores predicted PD at treatment start with the AUC of 0.66, 0.68, and 0.74 and after 6-8 weeks with the AUC of 0.76, 0.66, and 0.75. For external validation, 70 patients with mRCC were retrospectively included and all received TKI-containing regimens. The plasma score predicted PD at treatment start with the AUC of 0.90 and at 6-8 weeks with the AUC of 0.89. The pooled sensitivity and specificity were 58% and 79% at treatment start. Limitations include the exploratory study design.

CONCLUSION

GAGomes changed in association with mRCC response to TKIs and may provide biologic insights into mRCC mechanisms of response.

Proteoglycans: a common portal for SARS-CoV-2 and extracellular vesicle uptake

As structural components of the glycocalyx, heparan sulfate proteoglycans (HSPGs) are involved in multiple pathophysiological processes at the apex of cell signaling cascades, and as endocytosis receptors for particle structures, such as lipoproteins, extracellular vesicles, and enveloped viruses, including SARS-CoV-2. Given their diversity and complex biogenesis regulation, HSPGs remain understudied. Here we compile some of the latest studies focusing on HSPGs as internalizing receptors of extracellular vesicles ("endogenous virus") and SARS-CoV-2 lipid-enclosed particles and highlight similarities in their biophysical and structural characteristics. Specifically, the similarities in their biogenesis, size, and lipid composition may explain a common dependence on HSPGs for efficient cell-surface attachment and uptake. We further discuss the relative complexity of extracellular vesicle composition and the viral mechanisms that evolve towards increased infectivity that complicate therapeutic strategies addressing blockade of their uptake.

Glycosoaminoglycans in cancer therapy

Glycosaminoglycans (GAGs) are an important component of the tumor microenvironment (TME). GAGs can interact with a variety of binding partners and thereby influence cancer progression on multiple levels. GAGs can modulate growth factor and chemokine signaling, invasion and metastasis formation. Moreover, GAGs are able to change the physical property of the extracellular matrix (ECM). Abnormalities in GAG abundance and structure (e.g., sulfation patterns and molecular weight) are found across various cancer types and show biomarker potential. Targeting GAGs, as well as the usage of GAGs and their mimetics, are promising approaches to interfere with cancer progression. In addition, GAGs can be used as drug and cytokine carriers to induce an anti-tumor response. In this review, we summarize the role of GAGs in cancer and the potential use of GAGs and GAG derivatives to target cancer.

Integrated Omics Approaches Revealed the Osmotic Stress-Responsive Genes and Microbiota in Gill of Marine Medaka

This is the first study using the transcriptome and 16S rRNA gene sequencing to report the hypotonic responsive genes in gill cells and the compositions of gill microbiota in marine medaka. The overlapped glycosaminoglycan- and chitin-related pathways suggest host-bacterium interaction in fish gill during osmotic stress.

Heparan Sulfate Biosynthesis and Sulfation Profiles as Modulators of Cancer Signalling and Progression

Heparan Sulfate Proteoglycans (HSPGs) are important cell surface and Extracellular Matrix (ECM) maestros involved in the orchestration of multiple cellular events in physiology and pathology. These glycoconjugates bind to various bioactive proteins via their Heparan Sulfate (HS) chains, but also through the protein backbone, and function as scaffolds for protein-protein interactions, modulating extracellular ligand gradients, cell signalling networks and cell-cell/cell-ECM interactions. The structural features of HS chains, including length and sulfation patterns, are crucial for the biological roles displayed by HSPGs, as these features determine HS chains binding affinities and selectivity. The large HS structural diversity results from a tightly controlled biosynthetic pathway that is differently regulated in different organs, stages of development and pathologies, including cancer. This review addresses the regulatory mechanisms underlying HS biosynthesis, with a particular focus on the catalytic activity of the enzymes responsible for HS glycan sequences and sulfation motifs, namely D-Glucuronyl C5-Epimerase, N- and O-Sulfotransferases. Moreover, we provide insights on the impact of different HS structural epitopes over HSPG-protein interactions and cell signalling, as well as on the effects of deregulated expression of HS modifying enzymes in the development and progression of cancer. Finally, we discuss the clinical potential of HS biosynthetic enzymes as novel targets for therapy, and highlight the importance of developing new HS-based tools for better patients' stratification and cancer treatment.

A novel long non-coding RNA-based prognostic signature for renal cell carcinoma patients with stage IV and histological grade G4

This study aimed to establish a lncRNA-based signature for predicting the prognosis of patients with high stage and grade renal cell carcinoma (RCC). According to the Surveillance, Epidemiology, and End Results (SEER) database, sex, age, grade, stage, surgery, chemotherapy, radiation, tumor size, and marital status were the independent prognostic factors for RCC and also had significant correlations with the overall survival through Cox univariate and multivariate analyses. Noticeably, among these influencing factors, the histological classification of undifferentiated group and pathological stage IV had the greatest prognostic risks for RCC patients. Furthermore, based on the samples at stage IV and histological grade G4 from The Cancer Genome Atlas (TCGA) portal, 9 key lncRNAs, including KIAA2012, CCNT2-AS1, ITPKB-AS1, TBX2-AS1, NUTM2A-AS1, LINC02522, LINC02384, LINC01559, and LINC00865 were identified and a prognostic signature was constructed by Lasso analysis and Cox regression model. The Kaplan-Meier analysis suggested that patients at stage IV and histological grade of G4 in high risk score group had a worse overall survival than that in low risk score group. The following receiver operating characteristic curve (ROC) curves also showed that this signature possesses a better predictive power performance. Pathway enrichment analysis discovered that 9 lncRNAs held potential roles in cell division, cell cycle, DNA damage and cytokines levels in RCC. This work indicates that the established 9-lncRNA signature has a good capacity in predicting the prognosis of RCC patients with stage IV and histological grade of G4, and may be helpful for guiding the treatment strategies for RCC patients.

Chondroitin Sulfate Disaccharides, a Serum Marker for Primary Serous Epithelial Ovarian Cancer

Glycosaminoglycans are long polysaccharidic chains, which are mostly present in connective tissues. Modified GAG expression in tissues surrounding malignant cells has been shown to contribute to tumor progression, aggressive status and metastasis in many types of cancer. Ovarian cancer is one of the most lethal gynecological malignancies due to its late diagnosis because of the absence of clear symptoms and unavailability of early disease markers. We investigated for the first time GAG changes at the molecular level as a novel biomarker for primary epithelial ovarian cancer. To this end, serum of a cohort of 68 samples was digested with chondroitinase ABC, which releases chondroitin sulfate into disaccharides. After labeling and purification, they were measured by HPLC, yielding a profile of eight disaccharides. We proposed a novel GAG-based score named "CS- bio" from the measured abundance of disaccharides present that were of statistical relevance. CS-bio's performance was compared with CA125, the clinically used serum tumor marker in routine diagnostics. CS-bio had a better sensitivity and specificity than CA125. It was more apt in differentiating early-stage patients from healthy controls, which is of high interest for oncologists.

Urine and serum glycosaminoglycan levels in the diagnosis of urological diseases and conditions: A narrative review of the literature

Glycosaminoglycans (GAGs) are sulfated, negatively charged polysaccharides produced in almost every cell of the human body. As GAGs are extracellularly localized, the changes in body fluids such as blood and urine may reflect pathological changes in the urinary system as observed in other pathologies. In this review, we determined the potential of urinary and/or serum GAG levels as a marker for kidney and urothelial system diseases. We performed a search in the PubMed, MEDLINE, and ScienceDirect databases until September 30, 2019. A number of studies reported changes in the urinary and/or plasma GAG levels or composition in urological diseases and conditions, such as renal cell carcinoma, kidney stone, bladder carcinoma, and overactive bladder. GAGs were found to have a predictive biomarker potential that could be limited by generalizability concerns.

Peracylation Coupled with Tandem Mass Spectrometry for Structural Sequencing of Sulfated Glycosaminoglycan Mixtures without Depolymerization

The structures of glycosaminoglycans (GAGs), especially the patterns of modification, are crucial to modulate interactions with various protein targets. It is very challenging to determine the fine structures using liquid chromatography-mass spectrometry (LC-MS) due in large part to the gas-phase sulfate losses upon collisional activation. Previously, our group reported a method for fine structure analysis that required permethylation of the GAG oligosaccharide. However, uncontrolled depolymerization during the permethylation process due to esterification of uronic acid lowers the reliability of the method to resolve structures of GAGs, especially for larger oligosaccharides. Here, we describe a simplified derivatization method using propionylation and desulfation. The oligosaccharides have all hydroxyl and amine groups protected with propionyl groups and then have sulfate groups removed to generate unprotected hydroxyl and amine groups at all sites that were previously sulfated. This derivatized oligosaccharide generates informative fragments during collision-induced dissociation that resolve the original sulfation patterns. This method is demonstrated to enable accurate determination of sulfation patterns of even the highly sulfated pentasaccharide fondaparinux by MS² and MS³. Using a mixture of dp6 from porcine heparin, we demonstrate that this method allows for structural characterization of complex mixtures, including clear chromatographic separation and sequencing of structural isomers, all at high yields without evidence of depolymerization. This represents a marked improvement in the reliability to structurally characterize GAG oligosaccharides over permethylation-based derivatization schemes.

Glycosaminoglycan-Inspired Biomaterials for the Development of Bioactive Hydrogel Networks

Glycosaminoglycans (GAG) are long, linear polysaccharides that display a wide range of relevant biological roles. Particularly, in the extracellular matrix (ECM) GAG specifically interact with other biological molecules, such as growth factors, protecting them from proteolysis or inhibiting factors. Additionally, ECM GAG are partially responsible for the mechanical stability of tissues due to their capacity to retain high amounts of water, enabling hydration of the ECM and rendering it resistant to compressive forces. In this review, the use of GAG for developing hydrogel networks with improved biological activity and/or mechanical properties is discussed. Greater focus is given to strategies involving the production of hydrogels that are composed of GAG alone or in combination with other materials. Additionally, approaches used to introduce GAG-inspired features in biomaterials of different sources will also be presented.

Salt gradient chromatographic separation of chondroitin sulfate disaccharides

In the present study, we describe the development of a fast, 2-step salt gradient for analysis of chondroitin sulfate disaccharides. Using salt gradients, which is somewhat unusual in HILIC-based separations, provides relatively fast chromatography with excellent sensitivity (15 min cycle time, 10-20 fmol/µL detection, 30-50 fmol/µL quantitation limit), and good linearity. The efficiency of the new method is demonstrated by measuring human tissue slices of healthy, cirrhotic, and cancerous liver samples. Preliminary results show major differences among the quantity and sulfation pattern of the various sample types.

Chondroitin sulfate synthase 1 enhances proliferation of glioblastoma by modulating PDGFRA stability

Chondroitin sulfate synthases, a family of enzyme involved in chondroitin sulfate (CS) polymerization, are dysregulated in various human malignancies, but their roles in glioma remain unclear. We performed database analysis and immunohistochemistry on human glioma tissue, to demonstrate that the expression of CHSY1 was frequently upregulated in glioma, and that it was associated with adverse clinicopathologic features, including high tumor grade and poor survival. Using a chondroitin sulfate-specific antibody, we showed that the expression of CHSY1 was significantly associated with CS formation in glioma tissue and cells. In addition, overexpression of CHSY1 in glioma cells enhanced cell viability and orthotopic tumor growth, whereas CHSY1 silencing suppressed malignant growth. Mechanistic investigations revealed that CHSY1 selectively regulates PDGFRA activation and PDGF-induced signaling in glioma cells by stabilizing PDGFRA protein levels. Inhibiting PDGFR activity with crenolanib decreased CHSY1-induced malignant characteristics of GL261 cells and prolonged survival in an orthotopic mouse model of glioma, which underlines the critical role of PDGFRA in mediating the effects of CHSY1. Taken together, these results provide information on CHSY1 expression and its role in glioma progression, and highlight novel insights into the significance of CHSY1 in PDGFRA signaling. Thus, our findings point to new molecular targets for glioma treatment.

Salt and solvent effects in the microscale chromatographic separation of heparan sulfate disaccharides

The analysis of heparan sulfate disaccharides poses a real challenge both from chromatographic and mass spectrometric point of view. This necessitates the constant improvement of their analytical methodology. In the present study, the chromatographic effects of solvent composition, salt concentration, and salt type were systematically investigated in isocratic HILIC-WAX separations of heparan sulfate disaccharides. The combined use of 75% acetonitrile with ammonium formate had overall benefits regarding intensity, detection limits, and peak shape for all salt concentrations investigated. Results obtained with the isocratic measurements suggested the potential use of a salt gradient method in order to maximize separation efficiency. A 3-step gradient from 14 mM to 65 mM ammonium formate concentration proved to be ideal for separation and quantitation. The LOD of the resulting method was 0.8-1.5 fmol for the individual disaccharides and the LOQ was between 2.5-5 fmol. Outstanding linearity could be observed up to 2 pmol. This novel combination provided sufficient sensitivity for disaccharide analysis, which was demonstrated by the analysis of heparan sulfate samples from porcine and bovine origin.

The dual role of the glycosaminoglycan chondroitin-6-sulfate in the development, progression and metastasis of cancer

The remarkable structural heterogeneity of chondroitin sulfate (CS) and dermatan sulfate (DS) generates biological information that can be unique to each of these glycosaminoglycans (GAGs), and changes in their composition are translated into alterations in the binding profiles of these molecules. CS/DS can bind to various cytokines and growth factors, cell surface receptors, adhesion molecules, enzymes and fibrillar glycoproteins of the extracellular matrix, thereby influencing both cell behavior and the biomechanical and biochemical properties of the matrix. In this review, we summarize the current knowledge concerning CS/DS metabolism in the human cancer stroma. The remodeling of the GAG profile in the tumor niche is manifested as a substantial increase in the CS content and a gradual decrease in the proportion between DS and CS. Furthermore, the composition of CS and DS is also affected, which results in a substantial increase in the 6‐O‐sulfated and/or unsulfated disaccharide content, which is concomitant with a decrease in the 4‐O‐sulfation level. Here, we discuss the possible impact of alterations in the CS/DS sulfation pattern on the binding capacity and specificity of these GAGs. Moreover, we propose potential consequences of the stromal accumulation of chondroitin‐6‐sulfate for the progression and metastasis of cancer.

Plasma Glycosaminoglycans as Diagnostic and Prognostic Biomarkers in Surgically Treated Renal Cell Carcinoma

BACKGROUND

Plasma glycosaminoglycan (GAG) measurements, when aggregated into diagnostic scores, accurately distinguish metastatic clear-cell renal cell carcinoma (RCC) from healthy samples and correlate with prognosis. However, it is unknown if GAG scores can detect RCC in earlier stages or if they correlate with prognosis after surgery.

OBJECTIVE

To explore the sensitivity and specificity of plasma GAGs for detection of early-stage RCC and prediction of recurrence and death after RCC surgery.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective case-control study consisting of a consecutive series of 175 RCC patients surgically treated between May 2011 and February 2014 and 19 healthy controls.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Plasma GAGs in preoperative and postoperative RCC and healthy samples were measured using capillary electrophoresis with laser-induced fluorescence in a single blinded laboratory. A discovery set was first analyzed to update the historical GAG score. The sensitivity of the new GAG score for RCC detection versus healthy subjects was validated using the remaining samples. The correlation of the new GAG score to histopathologic variables, overall survival, and recurrence-free survival was evaluated using nonparametric and log-rank tests and multivariable Cox regression analyses.

RESULTS AND LIMITATIONS

The RCC cohort included 94 stage I, 58 stage II-III, and 22 stage IV cases. In the first discovery set (n=67), the new GAG score distinguished RCC from healthy samples with an area under the receiver operating characteristic curve (AUC) of 0.999. In the validation set (n=108), the GAG score achieved an AUC of 0.991, with 93.5% sensitivity. GAG scores were elevated in RCC compared to healthy samples, irrespective of and uncorrelated to stage, grade, histology, age, or gender. The total chondroitin sulfate concentration was an independent prognostic factor for both overall and recurrence-free survival (hazard ratios 1.51 and 1.25) with high concordance when combined with variables available at pathologic diagnosis (C-index 0.926 and 0.849) or preoperatively (C-index 0.846 and 0.736). Limitations of the study include its retrospective nature and moderate variability in GAG laboratory measurements.

CONCLUSIONS

Plasma GAGs are highly sensitive diagnostic and prognostic biomarkers in surgically treated RCC independent of stage, grade, or histology. Prospective validation studies on GAG scores for early detection, prediction, and surveillance for RCC recurrence are thus warranted.

PATIENT SUMMARY

In this study, we examined if a new molecular blood test can detect renal cell carcinoma in the early stages and predict if the cancer might relapse after surgery. The trial is registered on ClinicalTrial.gov as NCT03471897.

Sensitive method for glycosaminoglycan analysis of tissue sections

A simple, isocratic HPLC method based on HILIC-WAX separation, has been developed for analyzing sulfated disaccharides of glycosaminoglycans (GAGs). To our best knowledge, this is the first successful attempt using this special phase in nano-HPLC-MS analysis. Mass spectrometry was based on negative ionization, improving both sensitivity and specificity. Detection limit for most sulfated disaccharides were approximately 1 fmol; quantitation limits 10 fmol. The method was applied for glycosaminoglycan profiling of tissue samples, using surface digestion protocols. This novel combination provides sufficient sensitivity for GAG disaccharide analysis, which was first performed using prostate cancer tissue microarrays. Preliminary results show that GAG analysis may be useful for identifying cancer related changes in small amounts of tissue samples (ca. 10 μg).

Biodiversity of CS–proteoglycan sulphation motifs: chemical messenger recognition modules with roles in information transfer, control of cellular behaviour and tissue morphogenesis

Chondroitin sulphate (CS) glycosaminoglycan chains on cell and extracellular matrix proteoglycans (PGs) can no longer be regarded as merely hydrodynamic space fillers. Overwhelming evidence over recent years indicates that sulphation motif sequences within the CS chain structure are a source of significant biological information to cells and their surrounding environment. CS sulphation motifs have been shown to interact with a wide variety of bioactive molecules, e.g. cytokines, growth factors, chemokines, morphogenetic proteins, enzymes and enzyme inhibitors, as well as structural components within the extracellular milieu. They are therefore capable of modulating a panoply of signalling pathways, thus controlling diverse cellular behaviours including proliferation, differentiation, migration and matrix synthesis. Consequently, through these motifs, CS PGs play significant roles in the maintenance of tissue homeostasis, morphogenesis, development, growth and disease. Here, we review (i) the biodiversity of CS PGs and their sulphation motif sequences and (ii) the current understanding of the signalling roles they play in regulating cellular behaviour during tissue development, growth, disease and repair.

Glycosaminoglycans and glycolipids as potential biomarkers in lung cancer

In this report, we used liquid chromatography-mass spectrometry and Western blotting to analyze the content and structure of glycosaminoglycans, glycolipids and selected proteins to compare differences between patient-matched normal and cancerous lung tissues obtained from lung cancer patients. The cancer tissue samples contained over twice as much chondroitin sulfate (CS)/dermatan sulfate (DS) as did the normal tissue samples, while the amount of heparan sulfate (HS) and hyaluronan (HA) in normal and cancer tissues were not significantly different. In HS, several minor disaccharide components, including NS6S, NS2S and 2S were significantly lower in cancer tissues, while the levels of major disaccharides, TriS, NS and 0S disaccharides were not significantly different in normal and cancer tissues. In regards to CS/DS, the level of 4S disaccharide (the major component of CS-type A and DS) decreased and the level of 6S disaccharide (the major component of CS- type C) increased in cancer tissues. We also compared the content and structure of GAGs in lung tissues from smoking and non-smoking patients. Analysis of the glycolipids showed all lipids present in these lung tissues, with the exception of sphingomyelin were higher in cancer tissues than in normal tissues. Western analysis showed that syndecan 1 and 2 proteoglycans displayed much higher expression in cancer tissue/biopsy samples. This investigation begins to provide an understanding of patho-physiological roles on glycosaminoglycans and glycolipids and might be useful in identifying potential biomarkers in lung cancer.

Clinicopathological significance of ganglioside DSGb5 expression in renal cell carcinoma

Disialosyl globopentaosylceramide (DSGb5) is a ganglioside originally isolated from tissue extracts of renal cell carcinoma (RCC) with metastasis. Previous in vitro experiments have suggested that DSGb5 promotes metastasis by enhancing the migration of RCC cells and downregulating NK cell cytotoxicity against RCC cells. In this study, we investigated the clinicopathological significance of DSGb5 expression in RCC and outcomes of RCC patients. A total of 156 RCC patients who underwent surgical treatments at our hospital from January 2007 through December 2012 were analyzed in this study. The expression of DSGb5 in RCC specimens was examined by immunohistochemical staining with monoclonal antibody 5F3. The immunostaining intensity of RCC tissues was assessed in comparison with that in benign renal tubules as an internal positive control. The relationship between DSGb5 expression and clinicopathological characteristics was investigated and recurrence free survival following surgery was evaluated. Microvascular invasion was observed in 68% (n = 19/28) and in 45% (n = 58/128) of the DSGb5 high expression group and low expression group, respectively (p = 0.031). Of 156 patients with a median follow up of 51 months, 18 patients (12%) developed metastasis following surgery. Patients in the DSGb5 high expression group showed significantly lower recurrence-free survival as compared with those in the DSGb5 low expression group (log-rank P = 0.047). In the present study, DSGb5 expression was associated with microvascular invasion in RCC tissues, and patients with DSGb5 high expression showed significantly lower recurrence-free survival rates. These findings suggest that DSGb5 expressed in RCC is correlated with metastasis and is a potential predictor for identifying patients who experience metastasis after surgery.

Prognostic Value of Plasma and Urine Glycosaminoglycan Scores in Clear Cell Renal Cell Carcinoma

BACKGROUND

The prognosis of metastatic clear cell renal cell carcinoma (ccRCC) vastly improved since the introduction of antiangiogenic-targeted therapy. However, it is still unclear which biological processes underlie ccRCC aggressiveness and affect prognosis. Here, we checked whether a recently discovered systems biomarker based on plasmatic or urinary measurements of glycosaminoglycans (GAGs) aggregated into diagnostic scores correlated with ccRCC prognosis.

METHODS

Thirty-one patients with a diagnosis of ccRCC (23 metastatic) were prospectively enrolled, and their urine and plasma biomarker scores were correlated to progression-free survival (PFS) and overall survival (OS) as either a dichotomous ("Low" vs. "High") or a continuous variable in a multivariate survival analysis.

RESULTS

The survival difference between "High"- vs. "Low"-scored patients was significant in the case of urine scores (2-year PFS rate = 53.3 vs. 100%, p = 3 × 10-4 and 2-year OS rate = 73.3 vs. 100%, p = 0.0078) and in the case of OS for plasma scores (2-year PFS rate = 60 vs. 84%, p = 0.0591 and 2-year OS rate = 66.7 vs. 90%, p = 0.0206). In multivariate analysis, the urine biomarker score as a continuous variable was an independent predictor of PFS [hazard ratio (HR): 4.62, 95% CI: 1.66-12.83, p = 0.003] and OS (HR: 10.13, 95% CI: 1.80-57.04, p = 0.009).

CONCLUSION

This is the first report on an association between plasma or urine GAG scores and the prognosis of ccRCC patients. Prospective trials validating the prognostic and predictive role of this novel systems biomarker are warranted.