Increased expression of non-sulfated chondroitin correlates with adverse clinicopathological parameters in prostate cancer

Biomaterials and tissue engineering approaches using glycosaminoglycans for tissue repair: Lessons learned from the native extracellular matrix

Glycosaminoglycans (GAGs) are an important component of the extracellular matrix as they influence cell behavior and have been sought for tissue regeneration, biomaterials, and drug delivery applications. GAGs are known to interact with growth factors and other bioactive molecules and impact tissue mechanics. This review provides an overview of native GAGs, their structure, and properties, specifically their interaction with proteins, their effect on cell behavior, and their mechanical role in the ECM. GAGs' function in the extracellular environment is still being understood however, promising studies have led to the development of medical devices and therapies. Native GAGs, including hyaluronic acid, chondroitin sulfate, and heparin, have been widely explored in tissue engineering and biomaterial approaches for tissue repair or replacement. This review focuses on orthopaedic and wound healing applications. The use of GAGs in these applications have had significant advances leading to clinical use. Promising studies using GAG mimetics and future directions are also discussed. STATEMENT OF SIGNIFICANCE: Glycosaminoglycans (GAGs) are an important component of the native extracellular matrix and have shown promise in medical devices and therapies. This review emphasizes the structure and properties of native GAGs, their role in the ECM providing biochemical and mechanical cues that influence cell behavior, and their use in tissue regeneration and biomaterial approaches for orthopaedic and wound healing applications.

Theranostic Applications of Glycosaminoglycans in Metastatic Renal Cell Carcinoma

Renal cell carcinoma (RCC) makes up the majority of kidney cancers, with a poor prognosis for metastatic RCC (mRCC). Challenges faced in the management of mRCC, include a lack of reliable prognostic markers and biomarkers for precise monitoring of disease treatment, together with the potential risk of toxicity associated with more recent therapeutic options. Glycosaminoglycans (GAGs) are a class of carbohydrates that can be categorized into four main subclasses, viz., chondroitin sulfate, hyaluronic acid, heparan sulfate and keratan sulfate. GAGs are known to be closely associated with cancer progression and modulation of metastasis by modification of the tumor microenvironment. Alterations of expression, composition and spatiotemporal distribution of GAGs in the extracellular matrix (ECM), dysregulate ECM functions and drive cancer invasion. In this review, we focus on the clinical utility of GAGs as biomarkers for mRCC (which is important for risk stratification and strategizing effective treatment protocols), as well as potential therapeutic targets that could benefit patients afflicted with advanced RCC. Besides GAG-targeted therapies that holds promise in mRCC, other potential strategies include utilizing GAGs as drug carriers and their mimetics to counter cancer progression, and enhance immunotherapy through binding and transducing signals for immune mediators.

Robust one-pot multi-enzyme polysaccharide remodeling strategy for the synthesis of uniform chondroitin fragments and derivatives

The non-sulfated chondroitin backbone (CH) is the synthetic precursor of chondroitin sulfate, a linear polysaccharide with dramatic biological functions. Owing to the intrinsic characteristics of the polysaccharide biosynthetic pathway, it is still a challenge to obtain structural-defined glycans via microbial fermentation or enzymatic synthesis, which hindering the illustration of CH polysaccharide functions. Herein, we report a robust one-pot multi-enzyme polysaccharide remodeling strategy to synthesize uniform CH fragments and their derivatives. CH tetrasaccharide, which was obtained from the digestion of heterogeneous CH fragments, was used as the starting material to trigger the assembly of uniform CH fragments in a one-pot multi-enzyme system. This strategy, which combined heteropolymer digestion, sugar nucleotide in situ generation, and sugar chain synchronized polymerization, provides a robust toolbox for structural-defined polysaccharides synthesis.

KIF21A regulates breast cancer aggressiveness and is prognostic of patient survival and tumor recurrence

PURPOSE

Invasion of carcinoma cells into surrounding tissue affects breast cancer staging, influences choice of treatment, and impacts on patient outcome. KIF21A is a member of the kinesin superfamily that has been well-studied in congenital extraocular muscle fibrosis. However, its biological relevance in breast cancer is unknown. This study investigated the functional roles of KIF21A in this malignancy and examined its expression pattern in breast cancer tissue.

METHODS

The function of KIF21A in breast carcinoma was studied in vitro by silencing its expression in breast cancer cells and examining the changes in cellular activities. Immunohistochemical staining of breast cancer tissue microarrays was performed to determine the expression patterns of KIF21A.

RESULTS

Knocking down the expression of KIF21A using siRNA in MDA-MB-231 and MCF7 human breast cancer cells resulted in significant decreases in tumor cell migration and invasiveness. This was associated with reduced Patched 1 expression and F-actin microfilaments. Additionally, the number of focal adhesion kinase- and paxillin-associated focal adhesions was increased. Immunohistochemical staining of breast cancer tissue microarrays showed that KIF21A was expressed in both the cytoplasmic and nuclear compartments of carcinoma cells. Predominance of cytoplasmic KIF21A was significantly associated with larger tumors and high grade cancer, and prognostic of cause-specific overall patient survival and breast cancer recurrence.

CONCLUSION

The data demonstrates that KIF21A is an important regulator of breast cancer aggressiveness and may be useful in refining prognostication of this malignant disease.

Prospective Evaluation of Chondroitin Sulfate, Heparan Sulfate and Hyaluronic Acid in Prostate Cancer

Purpose:

The present study evaluates chondroitin sulfate (CS) and heparan sulfate (HS) in the urine and hyaluronic acid (HA) in the plasma of patients with prostate cancer before and after treatment compared to a control group.

Materials and Methods:

Plasma samples were used for HA dosage and urine for quantification of CS and HS from forty-four cancer patients and fourteen controls. Clinical, laboratory and radiological information were correlated with glycosaminoglycan quantification by statistical analysis.

Results:

Serum HA was significantly increased in cancer patients (39.68 ± 30.00 ng/ mL) compared to control group (15.04 ± 7.11 ng/mL; p=0.004) and was further increased in high-risk prostate cancer patients when compared to lower risk patients (p = 0.0214). Also, surgically treated individuals had a significant decrease in seric levels of heparan sulfate after surgical treatment, 31.05 ± 21.01 μg/mL (before surgery) and 23.14 ± 11.1 μg/mL (after surgery; p=0.029). There was no difference in the urinary CS and HS between prostate cancer patients and control group. Urinary CS in cancer patients was 27.32 ± 25.99 μg/mg creatinine while in the men unaffected by cancer it was 31.37 ± 28.37 μg/mg creatinine (p=0.4768). Urinary HS was 39.58 ± 32.81 μg/ mg creatinine and 35.29 ± 28.11 μg/mg creatinine, respectively, in cancer patients and control group (p=0.6252).

Conclusions:

Serum HA may be a useful biomarker for the diagnosis and prognosis of prostate cancer. However, urinary CS and HS did not altered in the present evaluation. Further studies are necessary to confirm these preliminary findings.

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.

Sulfation of Glycosaminoglycans and Its Implications in Human Health and Disorders

Sulfation is a dynamic and complex posttranslational modification process. It can occur at various positions within the glycosaminoglycan (GAG) backbone and modulates extracellular signals such as cell-cell and cell-matrix interactions; different sulfation patterns have been identified for the same organs and cells during their development. Because of their high specificity in relation to function, GAG sulfation patterns are referred to as the sulfation code. This review explores the role of GAG sulfation in different biological processes at the cell, tissue, and organism levels. We address the connection between the sulfation patterns of GAGs and several physiological processes and discuss the misregulation of GAG sulfation and its involvement in several genetic and metabolic disorders. Finally, we present the therapeutic potential of GAGs and their synthetic mimics in the biomedical field.

CHST11/13 Regulate the Metastasis and Chemosensitivity of Human Hepatocellular Carcinoma Cells Via Mitogen-Activated Protein Kinase Pathway

BACKGROUND

Carbohydrate sulfotransferases 11-13 (CHST11-13), that catalyze the transfer of sulfate to position 4 of the GalNAc residue of chondroitin, have been implicated in various diseases.

AIM

This study aimed to clarify the association of CHST11-13 expression with metastasis and drug sensitivity in hepatocellular carcinoma (HCC) cells.

METHODS

We measured the levels of CHST11 and CHST13 in a series of HCC cells using real-time PCR and Western blotting. After RNAi and forced expression treatment of CHST11 and CHST13 in MHCC97L and MHCC97H cells, metastatic potential and drug sensitivity of the two cells were investigated with ECM invasion assay, drug sensitivity assay, and in vivo antitumor activity assay. By real-time PCR and Western blotting, we explored the possible impacts of these two genes on mitogen-activated protein kinase (MAPK) signal pathway. MAPK pathway was blocked by PD98059 or SP600125 to elucidate the effects of MAPK pathway on metastasis and chemosensitivity.

RESULTS

Significantly reduced levels of CHST11 and CHST13 were observed in highly invasive MHCC97H cells compared with those of MHCC97L cell line with low metastatic potential. Decreased or forced expression of CHST11 and CHST13 altered metastatic potential and drug sensitivity of MHCC97L and MHCC97H cells. Remarkable alteration of MAPK activity was shown in two HCC cells with genetic manipulation. Conversely, pharmacologic inhibition of the MAPK pathway suppressed invasive potential and rescued drug sensitivity of MHCC97H cells.

CONCLUSIONS

Our results have demonstrated that CHST11 and CHST13 negatively modulate metastasis and drug resistance of HCC cells probably via oncogenic MAPK signal pathway.

Microanalysis of stomach cancer glycosaminoglycans

Glycosaminoglycans (GAGS) are anionic, linear, polysaccharides involved in cell signaling. The GAG content, composition and structure of human tissue have been suggested to play a role in cancer and might provide useful diagnostic or prognostic markers. The current study examines 17 stomach tissue biopsy samples taken from normal individuals and from patients with gastric cancers. An ultrasensitive liquid chromatography (LC) - mass spectrometry assay was applied to individual biopsy samples as small 250 μg providing GAG content and disaccharide composition. The results of these analyses show a significant increase in non-sulfated chondroitin/dermatan sulfate concentration in all cancer samples when compared to normal tissues. In addition in advanced gastric cancer, a significant decrease is observed in hyaluronan.

A structural analysis of glycosaminoglycans from lethal and nonlethal breast cancer tissues: toward a novel class of theragnostics for personalized medicine in oncology?

Cancer is one of the leading noncommunicable diseases that vastly impacts both developed and developing countries. Truly innovative diagnostics that inform disease susceptibility, prognosis, and/or response to treatment (theragnostics) are seriously needed for global public health and personalized medicine for patients with cancer. This study examined the structure and content of glycosaminoglycans (GAGs) in lethal and nonlethal breast cancer tissues from six patients. The glycosaminoglycan content isolated from tissue containing lethal cancer tumors was approximately twice that of other tissues. Molecular weight analysis showed that glycosaminoglycans from cancerous tissue had a longer weight average chain length by an average of five disaccharide units, an increase of approximately 15%. Dissacharide analysis found differences in sulfation patterns between cancerous and normal tissues, as well as sulfation differences in GAG chains isolated from patients with lethal and nonlethal cancer. Specifically, cancerous tissue showed an increase in sulfation at the "6S" position of CS chains and an increase in the levels of the HS disaccharide NSCS. Patients with lethal cancer showed a decrease in HS sulfation, with lower levels of "6S" and higher levels of the unsulfated "0S" disaccharide. Although these findings come from a limited sample size, they indicate that structural changes in GAGs exist between cancerous and noncancerous tissues and between tissues from patients with highly metastatic cancer and cancer that was successfully treated by chemotherapy. Based on these findings, we hypothesize that (1) there are putative changes in the body's construction of GAGs as tissue becomes cancerous; (2) there may be innate structural person-to-person variations in GAG composition that facilitate the metastasis of tumors in some patients when they develop cancer.

C4ST-1/CHST11-controlled chondroitin sulfation interferes with oncogenic HRAS signaling in Costello syndrome

Costello syndrome is a pediatric genetic disorder linked to oncogenic germline mutations in the HRAS gene. The disease is characterized by multiple developmental abnormalities, as well as predisposition to malignancies. Our recent observation that heart tissue from patients with Costello syndrome showed a loss of the glycosaminoglycan chondroitin-4-sulfate (C4S) inspired our present study aimed to explore a functional involvement of the chondroitin sulfate (CS) biosynthesis gene Carbohydrate sulfotransferase 11/Chondroitin-4-sulfotransferase-1 (CHST11/C4ST-1), as well as an impaired chondroitin sulfation balance, as a downstream mediator of oncogenic HRAS in Costello syndrome. Here we demonstrate a loss of C4S, as well as a reduction in C4ST-1 mRNA and protein expression, in primary fibroblasts from Costello syndrome patients. We go on to show that expression of oncogenic HRAS in normal fibroblasts can repress C4ST-1 expression, whereas interference with oncogenic HRAS signaling in Costello syndrome fibroblasts elevated C4ST-1 expression, thus identifying C4ST-1 as a negatively regulated target gene of HRAS signaling. Importantly, we show that forced expression of C4ST-1 in Costello fibroblasts could rescue the proliferation and elastogenesis defects associated with oncogenic HRAS signaling in these cells. Our results indicate reduced C4ST-1 expression and chondroitin sulfation imbalance mediating the effects of oncogenic HRAS signaling in the pathogenesis of Costello syndrome. Thus, our work identifies C4ST-1-dependent chondroitin sulfation as a downstream vulnerability in oncogenic RAS signaling, which might be pharmacologically exploited in future treatments of not only Costello syndrome and other RASopathies, but also human cancers associated with activating RAS mutations.

One-pot characterization of cancer cells by the analysis of mucin-type glycans and glycosaminoglycans

We developed an automated apparatus for rapid releasing of O-glycans from mucin-type glycoproteins [Anal. Biochem. 371 (2007) 52-61; Anal. Chem. 82 (2010) 7436-7443] and applied the device to analyze them in some cancer cell lines [J. Proteome Res. 8 (2009) 521-537]. We also found that the device is useful to release glycosaminoglycans from proteoglycans [Anal. Biochem. 362 (2007) 245-251]. Based on these studies, we developed a method for one-pot analysis of mucin-type glycans and glycosaminoglycans after releasing them from total protein pool obtained from some cancer cell lines. Mucin-type glycans were analyzed by a combination of high-performance liquid chromatography and mass spectrometry techniques, and glycosaminoglycans were analyzed by capillary electrophoresis as fluorescent-labeled unsaturated disaccharides after digestion with specific eliminases followed by fluorescent labeling. Ten cancer cell lines, including blood cancer cells as well as epithelial cancer cells, were used to assess the method. The results clearly revealed that both mucin-type glycans and glycosaminoglycans showed quite interesting profiles. Thus, the current technique will be a powerful tool for discovery of glycan markers of diseases.

Predicting sulfotyrosine sites using the random forest algorithm with significantly improved prediction accuracy

BACKGROUND

Tyrosine sulfation is one of the most important posttranslational modifications. Due to its relevance to various disease developments, tyrosine sulfation has become the target for drug design. In order to facilitate efficient drug design, accurate prediction of sulfotyrosine sites is desirable. A predictor published seven years ago has been very successful with claimed prediction accuracy of 98%. However, it has a particularly low sensitivity when predicting sulfotyrosine sites in some newly sequenced proteins.

RESULTS

A new approach has been developed for predicting sulfotyrosine sites using the random forest algorithm after a careful evaluation of seven machine learning algorithms. Peptides are formed by consecutive residues symmetrically flanking tyrosine sites. They are then encoded using an amino acid hydrophobicity scale. This new approach has increased the sensitivity by 22%, the specificity by 3%, and the total prediction accuracy by 10% compared with the previous predictor using the same blind data. Meanwhile, both negative and positive predictive powers have been increased by 9%. In addition, the random forest model has an excellent feature for ranking the residues flanking tyrosine sites, hence providing more information for further investigating the tyrosine sulfation mechanism. A web tool has been implemented at http://ecsb.ex.ac.uk/sulfotyrosine for public use.

CONCLUSION

The random forest algorithm is able to deliver a better model compared with the Hidden Markov Model, the support vector machine, artificial neural networks, and others for predicting sulfotyrosine sites. The success shows that the random forest algorithm together with an amino acid hydrophobicity scale encoding can be a good candidate for peptide classification.