Molecular characterization of kidney cancer: association of hyaluronic acid family with histological subtypes and metastasis

Hyaluronan-Mediated Motility Receptor (HMMR) Overexpression Is Correlated with Poor Survival in Patients with B-ALL

Acute lymphoblastic leukemia (ALL) is a malignant neoplasm with the highest incidence in the pediatric population. Although the 5-year overall survival is greater than 85%, in emerging countries such as Mexico, the mortality rate is high. In Mexico, B-ALL is the most common type of childhood cancer; different characteristics suggest the presence of the disease; however, the prognosis is dependent on clinical and laboratory features, and no adverse prognostic molecular marker for B-ALL has yet been identified. The present research aimed to identify the prognostic value of HMMR expression in pediatric patients with B-ALL. The differential expression profile of B-ALL cells was determined via in silico analysis, and HMMR expression was subsequently measured via qRT-PCR and immunocytochemistry. The results were statistically analyzed via the ROUT test, Kolmogorov-Smirnov Z test, and Mann-Whitney U test. ROC curves and the Youden index were constructed, and Kaplan-Meier curves were plotted. We found that HMMR expression was increased in B-ALL patients (p < 0.0001). We observed that high expression was related to poor prognosis (p < 0.05). We observed that high expression was related to poor prognosis (p < 0.05). The increase in HMMR expression could be a potential early molecular prognostic marker and/or a new target in childhood B-ALL patients.

The roles of hyaluronan in kidney development, physiology and disease

The hyaluronan (HA) matrix in the tissue microenvironment is crucial for maintaining homeostasis by regulating inflammatory signalling, endothelial-mesenchymal transition and cell migration. During development, covalent modifications and osmotic swelling of HA create mechanical forces that initiate midgut rotation, vascular patterning and branching morphogenesis. Together with its main cell surface receptor, CD44, HA establishes a physicochemical scaffold at the cell surface that facilitates the interaction and clustering of growth factors and receptors that is required for normal physiology. High-molecular-weight HA, tumour necrosis factor-stimulated gene 6, pentraxin 3 and CD44 form a stable pericellular matrix that promotes tissue regeneration and reduces inflammation. By contrast, breakdown of high-molecular-weight HA into depolymerized fragments by hyaluronidases triggers inflammatory signalling, leukocyte migration and angiogenesis, contributing to tissue damage and fibrosis in kidney disease. Targeting HA metabolism is challenging owing to its dynamic regulation and tissue-specific functions. Nonetheless, modulating HA matrix functions by targeting its binding partners holds promise as a therapeutic strategy for restoring tissue homeostasis and mitigating pathological processes. Further research in this area is warranted to enable the development of novel therapeutic approaches for kidney and other diseases characterized by dysregulated HA metabolism.

Differential expression analysis identifies a prognostically significant extracellular matrix-enriched gene signature in hyaluronan-positive clear cell renal cell carcinoma

Hyaluronan (HA) accumulation in clear cell renal cell carcinoma (ccRCC) is associated with poor prognosis; however, its biology and role in tumorigenesis are unknown. RNA sequencing of 48 HA-positive and 48 HA-negative formalin-fixed paraffin-embedded (FFPE) samples was performed to identify differentially expressed genes (DEG). The DEGs were subjected to pathway and gene enrichment analyses. The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma (TCGA-KIRC) data and DEGs were used for the cluster analysis. In total, 129 DEGs were identified. HA-positive tumors exhibited enhanced expression of genes related to extracellular matrix (ECM) organization and ECM receptor interaction pathways. Gene set enrichment analysis showed that epithelial-mesenchymal transition-associated genes were highly enriched in the HA-positive phenotype. A protein-protein interaction network was constructed, and 17 hub genes were discovered. Heatmap analysis of TCGA-KIRC data identified two prognostic clusters corresponding to HA-positive and HA-negative phenotypes. These clusters were used to verify the expression levels and conduct survival analysis of the hub genes, 11 of which were linked to poor prognosis. These findings enhance our understanding of hyaluronan in ccRCC.

Validation of novel DNA methylation markers in cervical precancer and cancer

We have recently identified, using a genome-wide approach, new methylation markers which were evaluated among various cervical intraepithelial neoplasia (CIN) grades and cervical cancer. We herein validate the methylated state of these genes in independent study populations, based on histology ascertained outcomes regardless of human papillomavirus status. CA10, DPP10, FMN2 and HAS1 (discovery set: 54 normal, 50 CIN1, 40 CIN2, 42 CIN3) were evaluated by targeted bisulfite next generation sequencing (NGS) (Illumina MiSeq platform) in 258 (training set: 100 normal, 50 CIN1, 50 CIN2, 50 CIN3, 8 cancers) and 373 (validation set: 100 normal, 57 CIN1, 61 CIN2, 53 CIN3, 102 cancers) physician-collected samples (PreservCyt). Using targeted amplification NGS data from the training set for 94 normal and eight cancer samples, we calculated for each gene the median methylation value. These were summed and normalized to compute a four-gene Marker Polygenic Score (MPS). We compared the relationship between MPS and progression from normal through CIN grades and cancer, separately in the training and validation sets, and tested its clinical performance via receiver-operating characteristic curves. MPS increased with increasing CIN grade, and accurately predicted cervical cancer in the training (area under the curve, AUC = 0.9950) and validation (AUC = 0.9337) sets, comparing normal to cancer. Using the highest threshold of 100% specificity, sensitivity for detection of cervical cancer was 67.7%; whereas reducing specificity to 95% increased sensitivity to 84.3%. Further evaluation of these biomarkers is warranted in prospective studies.

Teaching an Old Drug a New Trick: Targeting Treatment Resistance in Genitourinary Cancers

In the quest for improving the clinical outcome of patients with metastatic genitourinary cancers, including metastatic renal cell carcinoma (mRCC), the emphasis often is on finding new targeted therapies. However, two studies by Jordan et al. (Oncogenesis 2020) and Wang et al. (Cancer Cell Int 2022) demonstrate the feasibility of improving the efficacy of a modestly effective drug Sorafenib against mRCC by attacking a mechanism hijacked by RCC cells for inactivating Sorafenib. The studies also identified hyaluronic acid synthase -3 (HAS3) as a bonafide target of Sorafenib in RCC cells. The studies demonstrate that an over-the-counter drug Hymecromone (4-methylumbelliferone) blocks inactivation of Sorafenib in RCC cells and improves its efficacy against mRCC through the inhibition of HAS3 expression and HA signaling. In the broader context, improving the efficacy of "old and failed drugs" that have favorable safety profiles should increase the availability of effective treatments for patients with advanced cancers.

Hyaluronan Metabolism in Urologic Cancers

Hyaluronan (HA) is one of the major components of the extracellular matrix in tumor tissue. Recent reports have made it clear that the balance of HA synthesis and degradation is critical for tumor progression. HA is synthesized on the cytoplasmic surface of the plasma membrane by hyaluronan synthases (HAS) and extruded into the extracellular space. Excessive HA production in cancer is associated with enhanced HA degradation in the tumor microenvironment, leading to the accumulation of HA fragments with small molecular weight. These perturbations in both HA synthesis and degradation may play important roles in tumor progression. Recently, it has become increasingly clear that small HA fragments can induce a variety of biological events, such as angiogenesis, cancer-promoting inflammation, and tumor-associated immune suppression. Progression of urologic malignancies, particularly of prostate and bladder cancers, as well as of certain types of kidney cancer show markedly perturbed metabolism of tumor-associated HA. This review highlights the recent research findings regarding HA metabolism in tumor microenvironments with a special focus on urologic cancers. It also will discuss the potential implications of these findings for the development of novel therapeutic interventions for the treatment of prostate, bladder, and kidney cancers.

Hyaluronic acid: More than a carrier, having an overpowering extracellular and intracellular impact on cancer

Hyaluronic acid (HA), also named hyaluronan, is an omnipresent component of the tissue microenvironment. It is extensively used to formulate targeted drug delivery systems for cancer. Although HA itself has pivotal influences in various cancers, its calibers are somewhat neglected when using it as delivering platform to treat cancer. In the last decade, multiple studies revealed roles of HA in cancer cell proliferation, invasion, apoptosis, and dormancy through pathways like mitogen-activated protein kinase-extracellular signal-regulated kinase (MAPK/ERK), P³⁸, and nuclear factor kappa-light chain-enhancer of activated B cells (NFκB). A more fascinating fact is that the distinct molecular weight (MW) of HA exerts disparate effects on the same type of cancer. Its overwhelming use in cancer therapy and other therapeutic products make collective research on the sundry impact of it on various types of cancer, an essential aspect to be considered in all of these domains. Even the development of new therapies against cancer needed meticulous studies on HA because of its divergence of activity based on MW. This review will provide painstaking insight into the extracellular and intracellular bioactivity of HA, its modified forms, and its MW in cancers, which may improve the management of cancer.

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.

Role of Hyaluronic Acid in Selected Malignant Neoplasms in Women

Hyaluronic acid (HA) is a significant glycosaminoglycan component of the extracellular matrix, playing an essential role in cell localization and proliferation. However, high levels of HA may also correlate with multidrug resistance of tumor cells, an increased tendency to metastasize, or cancer progression, and thus represent a very unfavorable prognosis for cancer patients. The purpose of this review article is to summarize the results of studies describing the relationship between HA, the main ligand of the CD44 receptor, or other components of the HA signaling pathway. In addition, we review the course of selected female malignancies, i.e., breast, cervical, endometrial, and ovarian cancer, with the main focus on the mechanisms oriented to CD44. We also analyze reports on the beneficial use of HA-containing preparations in adjuvant therapy among patients with these types of cancer. Data from the literature suggest that HA and its family members may be critical prognostic biomarkers of selected malignancies among women. Nevertheless, the results of the available studies are inconclusive, and the actual clinical significance of HA expression analysis is still quite enigmatic. In our opinion, the HA-CD44 signaling pathway should be an attractive target for future research related to targeted therapy in gynecological cancers.

Targeting hyaluronic acid synthase-3 (HAS3) for the treatment of advanced renal cell carcinoma

BACKGROUND

Hyaluronic acid (HA) promotes cancer metastasis; however, the currently approved treatments do not target HA. Metastatic renal carcinoma (mRCC) is an incurable disease. Sorafenib (SF) is a modestly effective antiangiogenic drug for mRCC. Although only endothelial cells express known SF targets, SF is cytotoxic to RCC cells at concentrations higher than the pharmacological-dose (5-µM). Using patient cohorts, mRCC models, and SF combination with 4-methylumbelliferone (MU), we discovered an SF target in RCC cells and targeted it for treatment.

METHODS

We analyzed HA-synthase (HAS1, HAS2, HAS3) expression in RCC cells and clinical (n = 129), TCGA-KIRC (n = 542), and TCGA-KIRP (n = 291) cohorts. We evaluated the efficacy of SF and SF plus MU combination in RCC cells, HAS3-transfectants, endothelial-RCC co-cultures, and xenografts.

RESULTS

RCC cells showed increased HAS3 expression. In the clinical and TCGA-KIRC/TCGA-KIRP cohorts, higher HAS3 levels predicted metastasis and shorter survival. At > 10-µM dose, SF inhibited HAS3/HA-synthesis and RCC cell growth. However, at ≤ 5-µM dose SF in combination with MU inhibited HAS3/HA synthesis, growth of RCC cells and endothelial-RCC co-cultures, and induced apoptosis. The combination inhibited motility/invasion and an HA-signaling-related invasive-signature. We previously showed that MU inhibits SF inactivation in RCC cells. While HAS3-knockdown transfectants were sensitive to SF, ectopic-HAS3-expression induced resistance to the combination. In RCC models, the combination inhibited tumor growth and metastasis with little toxicity; however, ectopic-HAS3-expressing tumors were resistant.

CONCLUSION

HAS3 is the first known target of SF in RCC cells. In combination with MU (human equivalent-dose, 0.6-1.1-g/day), SF targets HAS3 and effectively abrogates mRCC.

Characterization of Hyaluronidase 4 Involved in the Catabolism of Chondroitin Sulfate

Hyaluronidases (HYALs) are endo-beta-N-acetylhexosaminidases that depolymerize not only hyaluronan but also chondroitin sulfate (CS) at the initial step of their catabolism. Although HYAL1 hydrolyzes both CS and HA, HYAL4 is a CS-specific endoglycosidase. The substrate specificity of HYAL4 and identification of amino acid residues required for its enzymatic activity have been reported. In this study, we characterized the properties of HYAL4 including the expression levels in various tissues, cellular localization, and effects of its overexpression on intracellular CS catabolism, using cultured cells as well as mouse tissues. Hyal4 mRNA and HYAL4 protein were demonstrated to be ubiquitously expressed in various organs in the mouse. HYAL4 protein was shown to be present both on cell surfaces as well as in lysosomes of rat skeletal muscle myoblasts, L6 cells. Overexpression of HYAL4 in Chinese hamster ovary cells decreased in the total amount of CS, suggesting its involvement in the cellular catabolism of CS. In conclusion, HYAL4 may be widely distributed and play various biological roles, including the intracellular depolymerization of CS.

New Insights Into Human Hyaluronidase 4/Chondroitin Sulphate Hydrolase

In this review, the current experimental evidence, literature and hypotheses surrounding hyaluronidase 4 [HYAL4, also known as chondroitin sulphate hydrolase (CHSE)] and chondroitin sulphate (CS) are explored. Originally named for its sequence similarity to other members of the hyaluronidase family, HYAL4 is actually a relatively distinct member of the family, particularly for its unique degradation of CS-D (2-O-, 6-O-sulphated CS) motifs and specific expression. Human HYAL4 protein expression and structural features are discussed in relation to different isoforms, activities, potential localisations and protein-protein interaction partners. CS proteoglycan targets of HYAL4 activity include: serglycin, aggrecan, CD44 and sulfatase 2, with other potential proteoglycans yet to be identified. Importantly, changes in HYAL4 expression changes in human disease have been described for testicular, bladder and kidney cancers, with gene mutations reported for several others including: leukaemia, endometrial, ovarian, colorectal, head and neck, stomach, lung and breast cancers. The HYAL4 gene also plays a role in P53 negative human cancer cell proliferation and is linked to stem cell naivety. However, its role in cancer remains relatively unexplored. Finally, current tools and techniques for the detection of specific HYAL4 activity in biological samples are critically assessed. Understanding the role of HYAL4 in human diseases will fortify our understanding of developmental processes and disease manifestation, ultimately providing novel diagnostic opportunities and therapeutic targets for drug discovery.

Roles of Proteoglycans and Glycosaminoglycans in Cancer Development and Progression

The extracellular matrix (ECM) spatiotemporally controls cell fate; however, dysregulation of ECM remodeling can lead to tumorigenesis and cancer development by providing favorable conditions for tumor cells. Proteoglycans (PGs) and glycosaminoglycans (GAGs) are the major macromolecules composing ECM. They influence both cell behavior and matrix properties through direct and indirect interactions with various cytokines, growth factors, cell surface receptors, adhesion molecules, enzymes, and glycoproteins within the ECM. The classical features of PGs/GAGs play well-known roles in cancer angiogenesis, proliferation, invasion, and metastasis. Several lines of evidence suggest that PGs/GAGs critically affect broader aspects in cancer initiation and the progression process, including regulation of cell metabolism, serving as a sensor of ECM's mechanical properties, affecting immune supervision, and participating in therapeutic resistance to various forms of treatment. These functions may be implemented through the characteristics of PGs/GAGs as molecular bridges linking ECM and cells in cell-specific and context-specific manners within the tumor microenvironment (TME). In this review, we intend to present a comprehensive illustration of the ways in which PGs/GAGs participate in and regulate several aspects of tumorigenesis; we put forward a perspective regarding their effects as biomarkers or targets for diagnoses and therapeutic interventions.

Molecular targeting of renal cell carcinoma by an oral combination

The 5-year survival rate of patients with metastatic renal cell carcinoma (mRCC) is <12% due to treatment failure. Therapeutic strategies that overcome resistance to modestly effective drugs for mRCC, such as sorafenib (SF), could improve outcome in mRCC patients. SF is terminally biotransformed by UDP-glucuronosyltransferase-1A9 (A9) mediated glucuronidation, which inactivates SF. In a clinical-cohort and the TCGA-dataset, A9 transcript and/or protein levels were highly elevated in RCC specimens and predicted metastasis and overall-survival. This suggested that elevated A9 levels even in primary tumors of patients who eventually develop mRCC could be a mechanism for SF failure. 4-methylumbelliferone (MU), a choleretic and antispasmodic drug, downregulated A9 and inhibited SF-glucuronidation in RCC cells. Low-dose SF and MU combinations inhibited growth, motility, invasion and downregulated an invasive signature in RCC cells, patient-derived tumor explants and/or endothelial-RCC cell co-cultures; however, both agents individually were ineffective. A9 overexpression made RCC cells resistant to the combination, while its downregulation sensitized them to SF treatment alone. The combination inhibited kidney tumor growth, angiogenesis and distant metastasis, with no detectable toxicity; A9-overexpressing tumors were resistant to treatment. With effective primary tumor control and abrogation of metastasis in preclinical models, the low-dose SF and MU combinations could be an effective treatment option for mRCC patients. Broadly, our study highlights how targeting specific mechanisms that cause the failure of “old” modestly effective FDA-approved drugs could improve treatment response with minimal alteration in toxicity profile.

Cellular hyaluronan is associated with a poor prognosis in renal cell carcinoma

PURPOSE

Hyaluronan, a major glycosaminoglycan of the extracellular matrix, can act as an oncogenic component of the tumor microenvironment in many human malignancies. We characterized the hyaluronan content of renal cell carcinomas (RCCs) and investigated its correlations with clinicopathological parameters and patient survival.

PATIENTS AND METHODS

This retrospective study included data from 316 patients that had undergone surgery for RCC in Kuopio University Hospital in 2000 to 2013. The hyaluronan content of surgical tumor samples were histochemically stained with a biotinylated hyaluronan-specific affinity probe. The amount of tumor infiltrating lymphocytes was evaluated in each tumor. Kaplan-Meier and univariate and multivariate Cox-regression analyses were performed to estimate the impact of hyaluronan content on overall survival, disease-specific survival, and metastasis-free survival.

RESULTS

Detectable cellular hyaluronan was associated with higher tumor grades and the presence of tumor infiltrating lymphocytes. Cellular hyaluronan identified a prognostically unfavourable subgroup among low-grade carcinomas. Multivariate analyses showed that measurable cellular hyaluronan was an independent negative prognostic factor for overall survival (hazard ratio [HR] 1.4; 95% confidence interval [CI]: 1.02-2.0; P = 0.039), Disease-specific survival (HR 2.07; 95% CI: 1.2-3.3; P = 0.002), and metastasis-free survival (HR 2.45; 95% CI: 1.37-4.4; P = 0.003).

CONCLUSIONS

Cellular hyaluronan was significantly associated with unfavourable features and a poor prognosis in RCC. Further studies are needed to investigate the biological mechanism underlying hyaluronan accumulation in RCC.

A chemokine/chemokine receptor signature potentially predicts clinical outcome in colorectal cancer patients

BACKGROUND

Differential expression of chemokines/chemokine receptors in colorectal cancer (CRC) may enable molecular characterization of patients' tumors for predicting clinical outcome.

OBJECTIVE

To evaluate the prognostic ability of these molecules in a CRC cohort and the CRC TCGA-dataset.

METHODS

Chemokine (CXCL-12α, CXCL-12β, IL-17A, CXCL-8, GM-CSF) and chemokine receptor (CXCR-4, CXCR-7) transcripts were analyzed by RT-qPCR in 76 CRC specimens (normal: 27, tumor: 49; clinical cohort). RNA-Seq data was analyzed from the TCGA-dataset (n= 375). Transcript levels were correlated with outcome; analyses: univariate, multivariable, Kaplan-Meier.

RESULTS

In the clinical cohort, chemokine/chemokine receptor levels were elevated 3-10-fold in CRC specimens (P⩽ 0.004) and were higher in patients who developed metastasis (P= 0.03 - < 0.0001). CXCR-4, CXCR-7, CXCL-12α, CXCL-8, IL-17 and GM-CSF levels predicted metastasis (P⩽ 0.0421) and/or overall survival (OS; P⩽ 0.0373). The CXCR-4+CXCR-7+CXCL-12 marker (CXCR-4/7+CXCL-12 (α/b) signature) stratified patients into risk for metastasis (P= 0.0014; OR, 2.72) and OS (P= 0.0442; OR, 2.7); sensitivity: 86.67%, specificity: 97.06%. In the TCGA-dataset, the CXCR-4/7+CXCL-12 signature predicted metastasis (P= 0.011; OR, 2.72) and OS (P= 0.0006; OR: 4.04). In both datasets, the signature was an independent predictor of clinical outcome.

CONCLUSIONS

Results of 451 specimens from both cohorts reveal that the CXCR-4/7+CXCL-12 signature potentially predicts outcome in CRC patients and may allow earlier intervention.

Improved Surface Display of Human Hyal1 and Identification of Testosterone Propionate and Chicoric Acid as New Inhibitors

Degradation of high molecular weight hyaluronic acid (HA) in humans is mainly catalyzed by hyaluronidase Hyal1. This enzyme is involved in many pathophysiological processes and therefore appears an interesting target for drug discovery. Until now, only a few inhibitors of human Hyal1 are known due to obstacles in obtaining active enzymes for inhibitor screening. The aim of the present work was to provide a convenient enzyme activity assay and show its feasibility by the identification of new inhibitors. By autodisplay, Escherichia coli F470 can present active Hyal1 on its surface. In this study, the inducible expression of Hyal1 on the cell surface of E. coli under the control of a rhamnose-dependent promoter (Prha) was performed and optimized. Enzyme activity per single cell was increased by a factor of 100 compared to the constitutive Hyal1 surface display, as described before. An activity of 6.8 × 10-4 mU per single cell was obtained under optimal reaction conditions. By this modified activity assay, two new inhibitors of human Hyal1 were identified. Chicoric acid, a natural compound belonging to the phenylpropanoids, showed an IC50 value of 171 µM. The steroid derivative testosterone propionate showed and IC50 value of 124 ± 1.1 µM. Both values were in the same order of magnitude as the IC50 value of glycyrrhizic acid (177 µM), one of the best known inhibitors of human Hyal1 known so far. In conclusion, we established a new enzyme activity assay for human Hyal1 and identified new inhibitors with this new assay method.

Genome-wide DNA methylation profiling identifies two novel genes in cervical neoplasia

DNA methylation analysis may improve risk stratification in cervical screening. We used a pan-epigenomic approach to identify new methylation markers along the continuum of cervical intraepithelial neoplasia (CIN) to cervical cancer. Physician-collected samples (54 normal, 50 CIN1, 40 CIN2 and 42 CIN3) were randomly selected from women at a single-center colposcopy clinic. Extracted DNA was subjected to Illumina Infinium EPIC array analysis, and methylation was assessed blinded to histopathological and clinical data. CpG sites whose state of methylation correlated with lesion grade were assessed (Spearman correlation), and a weighted methylation score was calculated comparing normal to CIN3. Validation of the top selected genes was performed in an independent cohort (100 normal, 50 CIN1, 50 CIN2, 50 CIN3 and 8 cervical cancers) of new patients, referred for colposcopic examination at three hospitals, using targeted DNA methylation Illumina amplicon sequencing. The relationship between a combined weighted marker score and progression from normal through precancerous lesions and cervical cancer was compared using one-way ANOVA. Our analyses revealed 7,715 CpGs whose methylation level correlated with progression (from normal to CIN1, CIN2 and CIN3), with a significant trend of increased methylation with lesion grade. We shortlisted a bigenic (hyaluronan synthase 1, HAS1 and ATPase phospholipid transporting 10A, ATP10A corresponding to cg03419058 and cg13944175 sites) marker set; r = 0.55, p < 0.0001. Validation of the four most discriminating genes (CA10, DPP10, FMN2 and HAS1) showed a significant correlation between methylation levels and disease progression (p-value < 2.2 × 10^-16 , adjusted R² = 0.952). Translational research of the identified genes to future clinical applications is warranted.

Hyaluronan in the Tumor Microenvironment

The extracellular matrix is part of the microenvironment and its functions are associated with the physical and chemical properties of the tissue. Among the extracellular components, the glycosaminoglycan hyaluronan is a key component, defining both the physical and biochemical characteristics of the healthy matrices. The hyaluronan metabolism is strictly regulated in physiological conditions, but in the tumoral tissues, its expression, size and binding proteins interaction are dysregulated. Hyaluronan from the tumor microenvironment promotes tumor cell proliferation, invasion, immune evasion, stemness alterations as well as drug resistance. This chapter describes data regarding novel concepts of hyaluronan functions in the tumor. Additionally, we discuss potential clinical applications of targeting HA metabolism in cancer therapy.

Immunohistochemical expression of CD44, matrix metalloproteinase2 and matrix metalloproteinase9 in renal cell carcinomas

PURPOSE

The aim of our study was to investigate the clinicopathologic values of the expression of CD44, matrix metalloproteinase (MMP)2, and MMP9 in renal cell carcinoma (RCC).

PATIENTS AND METHODS

A total of 107 clear cell RCCs (ccRCCs) and 32 nonclear cell RCCs (non-ccRCCs) were examined for CD44, MMP2, and MMP9 expression by immunohistochemistry. The membrane and cytoplasmic expression levels of the 3 proteins were scored by semiquantitative methods, and the correlations of the 3 proteins with clinicopathological parameters were verified.

RESULTS

The expression levels of CD44, MMP2, and MMP9 were positively correlated with nuclear grade (grade 1-2 vs. grade 3-4) (P = 0.003, P < 0.001 and P < 0.001, respectively) in the ccRCCs, while in the non-ccRCCs, only CD44 expression was correlated with higher nuclear grade (grade 1-3 vs. grade 4) (P = 0.001). Furthermore, CD44 expression in ccRCCs and non-ccRCCs was correlated with shorter overall survival in the univariate analyses (P < 0.001 and P = 0.015, respectively). In the multivariate analysis, which accounted for age, sex, nuclear grade, and pathologic stage, CD44 expression was an independent predictor of shorter overall survival only in ccRCCs. Correlations among the 3 proteins were all positive in ccRCCs, but in non-ccRCCs, only MMP2 and MMP9 were positively correlated.

CONCLUSION

CD44 expression may play an important role in the progression of both ccRCC and non-ccRCC. CD44 expression in ccRCC may be associated with elevated MMP2 and MMP9 expression levels, which is in contrast to non-ccRCC. The different correlations between CD44, MMP2, and MMP9 in ccRCC and non-ccRCC can be useful in understanding the mechanisms of carcinogenesis and stratifying patients for therapeutic purposes.

Molecular Characterization of Renal Cell Carcinoma: A Potential Three-MicroRNA Prognostic Signature

Background: Aberrantly expressed miRNAs promote renal cell carcinoma (RCC) growth and metastasis and are potentially useful biomarkers for metastatic disease. However, a consensus clinically significant miRNA signature has not been identified. To identify an miRNA signature for predicting clinical outcome in RCC patients, we used a four-pronged interconnected approach.Methods: Differentially expressed miRNAs were identified and analyzed in 113 specimens (normal kidney: 59; tumor: 54). miRNA profiling was performed in matched normal and tumor specimens from 8 patients and extended to 32 specimens. Seven aberrantly expressed miRNAs were analyzed by qPCR, and their levels were correlated with RCC subtypes and clinical outcome. miRNA signature was confirmed in The Cancer Genome Atlas RCC dataset (n = 241).Results: Discovery phase identified miR-21, miR-142-3p, miR-142-5p, miR-150, and miR-155 as significantly upregulated (2-4-fold) and miR-192 and miR-194 as downregulated (3-60-fold) in RCC; miR-155 distinguished small tumors (<4 cm) from benign oncocytomas. In univariate and multivariate analyses, miRNA combinations (miR-21+194; miR-21+142-5p+194) significantly predicted metastasis and/or disease-specific mortality; miR-21+142-5p+194 (for metastasis): P = 0.0017; OR, 0.53; 95% confidence interval (CI), 0.75-0.33; 86.7% sensitivity; 82% specificity. In the TCGA dataset, combined biomarkers associated with metastasis and overall survival (miR-21+142-5p+194: P < 0.0001; OR, 0.37; 95% CI, 0.58-0.23).Conclusions: The interconnected discovery-validation approach identified a three-miRNA signature as a potential predictor of disease outcome in RCC patients.Impact: With 10% survival at 5 years, metastatic disease presents poor prognosis for RCC patients. The three-miRNA signature discovered and validated may potentially at an early stage detect and predict metastasis, to allow early intervention for improving patient prognosis. Cancer Epidemiol Biomarkers Prev; 27(4); 464-72. ©2018 AACR.

Increased expression of CD44 is associated with more aggressive behavior in clear cell renal cell carcinoma

AIM

Although CD44 has been suggested as a prognostic marker in renal cell carcinoma (RCC), the prognostic significance of this marker in three main subtypes of RCC is still unclear. Thus, the present study was conducted to evaluate the expression and prognostic significance of CD44 as a cancer stem cell marker in different histological subtypes of RCC. Methodology & results: CD44 expression was evaluated in 206 well-defined renal tumor samples using immunohistochemistry on tissue microarrays. Higher CD44 expression was associated with more aggressive behavior, tumor progression and worse prognosis in clear cell RCC (ccRCC) but not in papillary and chromophobe RCC subtypes.

DISCUSSION & CONCLUSION

Cancer stem cell marker CD44 may be a promising target for cancer treatment only in ccRCC.

Human hyaluronic acid synthase-1 promotes malignant transformation via epithelial-to-mesenchymal transition, micronucleation and centrosome abnormalities

Background

Human hyaluronic acid (HA) molecules are synthesized by three membrane spanning Hyaluronic Acid Synthases (HAS1, HAS2 and HAS3). Of the three, HAS1 is found to be localized more into the cytoplasmic space where it synthesizes intracellular HA. HA is a ubiquitous glycosaminoglycan, mainly present in the extracellular matrix (ECM) and on the cell surface, but are also detected intracellularly. Accumulation of HA in cancer cells, the cancer-surrounding stroma, and ECM is generally considered an independent prognostic factors for patients. Higher HA production also correlates with higher tumor grade and more genetic heterogeneity in multiple cancer types which is known to contribute to drug resistance and results in treatment failure. Tumor heterogeneity and intra-tumor clonal diversity are major challenges for diagnosis and treatment. Identification of the driver pathway(s) that initiate genomic instability, tumor heterogeneity and subsequent phenotypic/clinical manifestations, are fundamental for the diagnosis and treatment of cancer. Thus far, no evidence was shown to correlate intracellular HA status (produced by HAS1) and the generation of genetic diversity in tumors.

Methods

We tested different cell lines engineered to induce HAS1 expression. We measured the epithelial traits, centrosomal abnormalities, micronucleation and polynucleation of those HAS1-expressing cells. We performed real-time PCR, 3D cell culture assay, confocal microscopy, immunoblots and HA-capture methods.

Results

Our results demonstrate that overexpression of HAS1 induces loss of epithelial traits, increases centrosomal abnormalities, micronucleation and polynucleation, which together indicate manifestation of malignant transformation, intratumoral genetic heterogeneity, and possibly create suitable niche for cancer stem cells generation.

Conclusions

The intracellular HA produced by HAS1 can aggravate genomic instability and intratumor heterogeneity, pointing to a fundamental role of intracellular HA in cancer initiation and progression.

Electronic supplementary material

The online version of this article (10.1186/s12964-017-0204-z) contains supplementary material, which is available to authorized users.

Hyaluronic acid family in bladder cancer: potential prognostic biomarkers and therapeutic targets

Background:

Molecular markers of clinical outcome may aid in designing targeted treatments for bladder cancer. However, only a few bladder cancer biomarkers have been examined as therapeutic targets.

Methods:

Data from The Cancer Genome Atlas (TCGA) and bladder specimens were evaluated to determine the biomarker potential of the hyaluronic acid (HA) family of molecules – HA synthases, HA receptors and hyaluronidase. The therapeutic efficacy of 4-methylumbelliferone (4MU), a HA synthesis inhibitor, was evaluated in vitro and in xenograft models.

Results:

In clinical specimens and TCGA data sets, HA synthases and hyaluronidase-1 levels significantly predicted metastasis and poor survival. 4-Methylumbelliferone inhibited proliferation and motility/invasion and induced apoptosis in bladder cancer cells. Oral administration of 4MU both prevented and inhibited tumour growth, without dose-related toxicity. Effects of 4MU were mediated through the inhibition of CD44/RHAMM and phosphatidylinositol 3-kinase/AKT axis, and of epithelial–mesenchymal transition determinants. These were attenuated by HA, suggesting that 4MU targets oncogenic HA signalling. In tumour specimens and the TCGA data set, HA family expression correlated positively with β-catenin, Twist and Snail expression, but negatively with E-cadherin expression.

Conclusions:

This study demonstrates that the HA family can be exploited for developing a biomarker-driven, targeted treatment for bladder cancer, and 4MU, a non-toxic oral HA synthesis inhibitor, is one such candidate.

Long noncoding RNA HAS2-AS1 mediates hypoxia-induced invasiveness of oral squamous cell carcinoma

A hypoxic microenvironment plays important roles in the progression of solid tumors, including oral squamous cell carcinoma (OSCC). Long noncoding RNAs (lncRNAs) have gained much attention in the past few years. However, it is not clear whether lncRNAs can regulate hypoxia adaptation of OSCC or which lncRNAs participate in this process. Using a lncRNA microarray, we analyzed the aberrant lncRNA expression profiles in OSCC tissues compared with paired normal oral mucosa and in hypoxic OSCC cells compared with normoxic OSCC cells. The top 10 lncRNAs that had more than threefold increase with P-value <0.01 in both microarray data were validated by qRT-PCR. Among the top 10 lncRNAs, hyaluronan synthase 2 antisense 1 (HAS2-AS1) was the only one that has a hypoxia-responsive element (HRE) on its promoter region and has been validated to increase in OSCC tissues and in cells cultured under hypoxia. Tumor HAS2-AS1 levels were closely associated with lymph node metastasis and hypoxic tumor status in patients with OSCC. Moreover, the hypoxia-induced HAS2-AS1 expression is dependent on HIF-1α which directly binds to and activates the transcription of HAS2-AS1. In addition, HAS2-AS1 mediates hypoxia-induced epithelial mesenchymal transition of OSCC cells via stabilizing HAS2. In conclusion, our results suggest that hypoxia would induce an overexpression of HAS2-AS1 in an HIF-1α dependent manner. The increase of HAS2-AS1 plays important roles mediating the hypoxia-regulated EMT and invasiveness of OSCC.

Hyaluronan synthase 2 expressed by cancer-associated fibroblasts promotes oral cancer invasion

BACKGROUND

Hyaluronan synthases (HAS) control the biosynthesis of hyaluronan (HA) and critically modulate the tumor microenviroment. Cancer-associated fibroblasts (CAFs) affect the progression of a tumor by remolding the matrix. However, little is known about the role of HAS from CAFs in this process. This study aimed to determine the role of hyaluronan synthase 2 (HAS2) from CAFs in the progression of oral squamous cell carcinoma (OSCC) invasion.

METHODS

HAS isoforms 1, 2, and 3 in paired sets of CAFs and normal fibroblasts (NFs) were examined by real-time PCR, and the expression of HAS2 and α-SMA in OSCC tissue sections was further evaluated using immunohistochemical staining. Furthermore, we used a conditioned culture medium model to evaluate the effects of HAS2 from CAFs on the invasion and epithelial-mesenchymal transition (EMT) of the oral cancer cells Cal27. Finally, we compared the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) between CAFs and NF, and between CAFs with or without HAS2 knockdown using an antibody array and western blotting.

RESULTS

CAFs expressed higher levels of HAS2 than the paired NFs. HAS2 expression was consistent with α-SMA-positive myofibroblasts in the stroma of OSCC, and these were significantly correlated advanced clinical stages and cervical lymph node metastasis. Knocking down HAS2 with a specific siRNA or treatment with a HAS inhibitor markedly attenuated CAF-induced invasion and EMT of Cal27 cells. Higher MMP1 and lower TIMP1 levels were detected in the supernatants of CAFs relative to NFs. Knocking down HAS2 could decrease the expression of MMP1 and increase that of TIMP1 in CAFs.

CONCLUSIONS

HAS2 is one of the key regulators responsible for CAF-mediated OSCC progression and acts by modulating the balance of MMP1 and TIMP1.

Increased Expression of HYAL1 in Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Increased production and processing (degradation) of hyaluronan (HA) is critical for cancer invasion and metastasis. Although HA is known to be overexpressed in pancreatic ductal adenocarcinoma (PDAC), little is known about the expression and biological significance of HA-degrading enzymes, hyaluronidases (HYALs), in PDAC.

METHODS

Expression of HYALs mRNA was examined in PDAC cells by quantitative real-time RT-PCR. HYAL1 protein expression was examined in primary PDAC tumors by enzyme-linked immuno-sorbent assay. The migratory ability of PDAC cells was determined by a transwell cell migration assay.

RESULTS

Screening of mRNA expression of three major HYAL genes (HYAL1, 2, and 3) identified HYAL1 as a gene overexpressed in PDAC cells. Treatment of PDAC cells with 5-aza-2'-deoxycytidine and/or trichostatin A further increased the HYAL1 expression, suggesting a possible involvement of epigenetic mechanisms in the transcriptional regulation of this gene. HYAL1 protein concentrations were significantly higher in primary PDAC tissues as compared with nontumor pancreatic tissues (P = 0.049). Importantly, inhibition of HYAL activity by dextran sulfate significantly inhibited the migration of PDAC cells showing strong HYAL1 expression (P = 0.002).

CONCLUSIONS

These findings suggest that overexpression of HYAL1 is a common mechanism that may contribute to the aggressive phenotype of PDAC.

Role of hyaluronan in pancreatic cancer biology and therapy: Once again in the spotlight

Pancreatic ductal adenocarcinoma (PDAC) remains the most deadly disease worldwide, with the lowest survival rate among all cancer types. Recent evidence suggests that hyaluronan (HA), a major component of ECM, provides a favorable microenvironment for cancer progression. Pancreatic ductal adenocarcinoma is typically characterized by a dense desmoplastic stroma containing a large amount of HA. Accumulation of HA promotes tumor growth in mice and correlates with poor prognosis in patients with PDAC. Because HA is involved in various malignant behaviors of cancer (such as increased cell proliferation, migration, invasion, angiogenesis, and chemoresistance), inhibiting HA synthesis/signaling or depleting HA in tumor stroma could represent a promising therapeutic strategy against PDAC. In this review article, we summarize our current understanding of the role of HA in the progression of PDAC and discuss possible therapeutic approaches targeting HA.

Prognostic value of CD44 expression in renal cell carcinoma: a systematic review and meta-analysis

CD44 is a marker of cancer stem-like cells in renal cell carcinoma (RCC). However, the prognostic value of CD44 in RCC remains controversial. This study evaluated the correlation of CD44 expression with the clinicopathological features of RCC through a meta-analysis. We systematically searched PubMed, ISI Web of Science and Embase for relevant studies until February 2015. We collected and analysed data on clinical stage, Fuhrman grade, microvascular invasion, recurrence, five-year overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS). Twenty studies involving 1672 patients satisfied the inclusion criteria. Results showed that high CD44 expression in RCC was a poor prognostic marker for five-year OS (RR = 0.69, 95% CI 0.60–0.78) in a fixed-effects model and for five-year DSS (RR = 0.46, 95% CI 0.27–0.80) and five-year DFS (RR = 0.63, 95% CI 0.43–0.93) in a random-effects model. CD44 expression also correlated with Furhman grade (RR = 0.61, 95% CI 0.48–0.77), tumour recurrence (RR = 7.42, 95% CI 3.74–14.70) and MVI (Microvascular invasion) (RR = 3.63, 95% CI 1.97–6.71). This meta-analysis suggests that CD44 is a prognostic marker in RCC. High CD44 expression correlates with high Fuhrman grade, recurrence, MVI and poor prognosis.

Emerging roles for hyaluronidase in cancer metastasis and therapy

Hyaluronidases are a family of five human enzymes that have been differentially implicated in the progression of many solid tumor types, both clinically and in functional studies. Advances in the past 5 years have clarified many apparent contradictions: (1) by demonstrating that specific hyaluronidases have alternative substrates to hyaluronan (HA) or do not exhibit any enzymatic activity, (2) that high-molecular weight HA polymers elicit signaling effects that are opposite those of the hyaluronidase-digested HA oligomers, and (3) that it is actually the combined overexpression of HA synthesizing enzymes with hyaluronidases that confers tumorigenic potential. This review examines the literature supporting these conclusions and discusses novel mechanisms by which hyaluronidases impact invasive tumor cell processes. In addition, a detailed structural and functional comparison of the hyaluronidases is presented with insights into substrate selectivity and potential for therapeutic targeting. Finally, technological advances in targeting hyaluronidase for tumor imaging and cancer therapy are summarized.

Targeting hyaluronic acid family for cancer chemoprevention and therapy

Hyaluronic acid or hyaluronan (HA) is perhaps one of the most uncomplicated large polymers that regulates several normal physiological processes and, at the same time, contributes to the manifestation of a variety of chronic and acute diseases, including cancer. Members of the HA signaling pathway (HA synthases, HA receptors, and HYAL-1 hyaluronidase) have been experimentally shown to promote tumor growth, metastasis, and angiogenesis, and hence each of them is a potential target for cancer therapy. Furthermore, as these members are also overexpressed in a variety of carcinomas, targeting of the HA family is clinically relevant. A variety of targeted approaches have been developed to target various HA family members, including small-molecule inhibitors and antibody and vaccine therapies. These treatment approaches inhibit HA-mediated intracellular signaling that promotes tumor cell proliferation, motility, and invasion, as well as induction of endothelial cell functions. Being nontoxic, nonimmunogenic, and versatile for modifications, HA has been used in nanoparticle preparations for the targeted delivery of chemotherapy drugs and other anticancer compounds to tumor cells through interaction with cell-surface HA receptors. This review discusses basic and clinical translational aspects of targeting each HA family member and respective treatment approaches that have been described in the literature.

Dietary supplement 4-methylumbelliferone: an effective chemopreventive and therapeutic agent for prostate cancer

BACKGROUND

Prevention and treatment of advanced prostate cancer (PCa) by a nontoxic agent can improve outcome, while maintaining quality of life. 4-methylumbelliferone (4-MU) is a dietary supplement that inhibits hyaluronic acid (HA) synthesis. We evaluated the chemopreventive and therapeutic efficacy and mechanism of action of 4-MU.

METHODS

TRAMP mice (7-28 per group) were gavaged with 4-MU (450mg/kg/day) in a stage-specific treatment design (8-28, 12-28, 22-28 weeks). Efficacy of 4-MU (200-450mg/kg/day) was also evaluated in the PC3-ML/Luc(+) intracardiac injection and DU145 subcutaneous models. PCa cells and tissues were analyzed for HA and Phosphoinositide 3-kinase (PI-3K)/Akt signaling and apoptosis effectors. HA add-back and myristoylated Akt (mAkt) overexpression studies evaluated the mechanism of action of 4-MU. Data were analyzed with one-way analysis of variance and unpaired t test or Tukey's multiple comparison test. All statistical tests were two-sided.

RESULTS

While vehicle-treated transgenic adenocarcinoma of the prostate (TRAMP) mice developed prostate tumors and metastases at 28 weeks, both were abrogated in treatment groups, without serum/organ toxicity or weight loss; no tumors developed at one year, even after stopping the treatment at 28 weeks. 4-MU did not alter the transgene or neuroendocrine marker expression but downregulated HA levels. However, 4-MU decreased microvessel density and proliferative index (P < .0001,). 4-MU completely prevented/inhibited skeletal metastasis in the PC3-ML/Luc(+) model and DU145-tumor growth (85-90% inhibition, P = .002). 4-MU also statistically significantly downregulated HA receptors, PI-3K/CD44 complex and activity, Akt signaling, and β-catenin levels/activation, but upregulated GSK-3 function, E-cadherin, and apoptosis effectors (P < .001); HA addition or mAkt overexpression rescued these effects.

CONCLUSION

4-MU is an effective nontoxic, oral chemopreventive, and therapeutic agent that targets PCa development, growth, and metastasis by abrogating HA signaling.

Role of receptor for hyaluronan-mediated motility (RHAMM) in human head and neck cancers

The receptor for hyaluronan (HA)-mediated motility (RHAMM) is a HA-binding protein located in the cytoskeleton and centrosome. RHAMM has multiple functions that manifest with different cellular localizations, for example, modulation of growth factor receptor, regulation of cell signaling pathways, and mitotic spindle assembly. In addition, its increased expression has major roles in tumorigenesis and can induce genomic instability and cancer progression. In head and neck cancers, increased expression of RHAMM is associated with high proliferation of cancer cells and decreased survival. CD44, a cell-adhesion molecule and HA receptor, can modulate intracellular signaling by forming complexes with RHAMM to promote invasion and metastasis of cancer cells. In this review, we provide an overview of the biological functions of RHAMM in non-neoplastic cells and cancer cells, as well as its association with CD44, and also introduce studies that particularly implicate RHAMM in the pathogenesis of head and neck cancers.

Molecular marker for predicting treatment response in advanced renal cell carcinoma: does the promise fulfill clinical need?

Renal cell carcinoma (RCC) is largely diagnosed incidentally on imaging taken for unrelated reasons. The management of localized lesions is primarily extirpative with excellent results. Treatment of advanced RCC has evolved over recent years with the use of targeted therapies such as tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, and antibody-mediated therapies. The treatment response to these targeted therapies is highly variable, with no clear clinical method of identifying patients who will benefit from or not tolerate therapy. The field of molecular markers has evolved significantly in the last decade, with a multitude of markers identified that predict treatment response and drug toxicity. The following review critically evaluates those molecular markers that have been assessed for their utility in predicting treatment response in patients with advanced/metastatic renal cell carcinoma (mRCC). Identifying the ideal treatment for these patients will improve responses to therapy, minimize morbidity, and save significant healthcare dollars.

Hyaluronan: towards novel anti-cancer therapeutics

The understanding of the role of hyaluronan in physiology and various pathological conditions has changed since the complex nature of its synthesis, degradation and interactions with diverse binding proteins was revealed. Initially perceived only as an inert component of connective tissue, it is now known to be involved in multiple signaling pathways, including those involved in cancer pathogenesis and progression. Hyaluronan presents a mixture of various length polymer molecules from finely fragmented oligosaccharides, polymers intermediate in size, to huge aggregates of high molecular weight hyaluronan. While large molecules promote tissue integrity and quiescence, the generation of breakdown products enhances signaling transduction, contributing to the pro-oncogenic behavior of cancer cells. Low molecular weight hyaluronan has well-established angiogenic properties, while the smallest hyaluronan oligomers may counteract tumor development. These equivocal properties make the role of hyaluronan in cancer biology very complex. This review surveys recent data on hyaluronan biosynthesis, metabolism, and interactions with its binding proteins called hyaladherins (CD44, RHAMM), providing themolecular background underlying its differentiated biological activity. In particular, the article critically presents current ideas on actual role of hyaluronan in cancer. The paper additionally maps a path towards promising novel anti-cancer therapeutics which target hyaluronan metabolic enzymes and hyaladherins, and constitute hyaluronan-based drug delivery systems.

Hyaluronan synthases (HAS1-3) in stromal and malignant cells correlate with breast cancer grade and predict patient survival

Accumulation of hyaluronan (HA) in pericellular stroma and carcinoma cells is predictive of unfavorable patient prognosis in many epithelial cancers. However, it is not known whether the HA originates from carcinoma or stromal cells, or whether increased expression of hyaluronan synthase proteins (HAS1-3) contributes to HA accumulation. In this study, localization and expression of HAS1-3 were evaluated immunohistochemically in 278 cases of human breast cancer, and correlated with prognostic factors and patient outcome. Both carcinoma cells and stromal cells were HAS-positive. In carcinoma cells, HAS1 and HA stainings correlated with each other, and HAS1 associated with estrogen receptor negativity, HER2 positivity, high relapse rate, and short overall survival. In stromal cells, the staining levels of all HAS isoforms correlated with the stromal HA staining, stromal cell CD44, high relapse rate, and short overall survival of the patients. In addition, expression levels of stromal HAS1 and HAS2 were related to obesity, large tumor size, lymph node positivity, and estrogen receptor negativity. Thus, stromal HAS1 and HAS3 were independent prognostic factors in the multivariate analysis. The data suggest that increased levels of HAS enzymes contribute to the accumulation of HA in breast cancer, and that HA is synthesized in carcinoma cells and stromal cells. The study also indicates that HAS enzyme levels are related to tumor aggressiveness and poor patient outcome representing potential targets for therapy.

Establishment and characterization of clear cell renal cell carcinoma cell lines with different metastatic potential from Chinese patients

Abstracts

Dietary supplement hymecromone and sorafenib: a novel combination for the control of renal cell carcinoma

PURPOSE

Current treatments for metastatic renal cell carcinoma do not extend survival beyond a few months. Sorafenib is a targeted drug approved for metastatic renal cell carcinoma but it has modest efficacy. Hymecromone is a nontoxic dietary supplement with some antitumor activity at high doses of 450 to 3,000 mg per day. Hymecromone inhibits the synthesis of hyaluronic acid, which promotes tumor growth and metastasis. We recently noted that the hyaluronic acid receptors CD44 and RHAMM are potential predictors of metastatic renal cell carcinoma. In the current study we examined the antitumor properties of hymecromone, sorafenib and the combination in renal cell carcinoma models.

MATERIALS AND METHODS

Using proliferation, clonogenic and apoptosis assays, we examined the effects of hymecromone (0 to 32 μg/ml), sorafenib (0 to 3.2 μg/ml) and hymecromone plus sorafenib in Caki-1, 786-O, ACHN and A498 renal cell carcinoma cells, and HMVEC-L and HUVEC endothelial cells. A Boyden chamber was used for motility and invasion assays. Apoptosis indicators, hyaluronic acid receptors, epidermal growth factor receptor and c-Met were evaluated by immunoblot. The efficacy of hymecromone, sorafenib and hymecromone plus sorafenib was assessed in the sorafenib resistant Caki-1 xenograft model.

RESULTS

Hymecromone plus sorafenib synergistically inhibited proliferation (greater than 95%), motility/invasion (65%) and capillary formation (76%) in renal cell carcinoma and/or endothelial cells, and induced apoptosis eightfold (p <0.001). Hymecromone plus sorafenib inhibited hyaluronic acid synthesis and adding hyaluronic acid reversed the cytotoxicity of hymecromone plus sorafenib. Hymecromone plus sorafenib up-regulated pro-apoptotic indicators and down-regulated Mcl-1, CD44, RHAMM, phospho-epidermal growth factor receptor and phospho-cMet. In all assays hymecromone and sorafenib alone were ineffective. Oral administration of hymecromone (50 to 200 mg/kg) plus sorafenib (30 mg/kg) eradicated Caki-1 tumor growth without toxicity. Hymecromone and sorafenib alone were ineffective.

CONCLUSIONS

To our knowledge this is the first study to show that the combination of sorafenib and the nontoxic dietary supplement hymecromone is highly effective for controlling renal cell carcinoma.

Chemokine and chemokine receptor expression in kidney tumors: molecular profiling of histological subtypes and association with metastasis

PURPOSE

Molecular characterization of renal cell carcinoma may help differentiate benign oncocytoma from malignant renal cell carcinoma subtypes and predict metastasis. Chemokines, eg IL-8 and chemokine receptors such as CXCR4 and 7, promote inflammation and metastasis. SDF-1 is a CXCR4 and 7 ligand with 6 known isoforms. We evaluated the expression of these chemokines and chemokine receptors in kidney specimens.

MATERIALS AND METHODS

Using quantitative polymerase chain reaction we measured mRNA levels of IL-8, CXCR4 and 7, and SDF1 isoforms α, β and γ in a total of 166 specimens from 86 patients, including 86 tumor samples and 80 matched normal kidney samples. Mean ± SD followup was 18.9 ± 12 months (median 19.5). Renal cell carcinoma specimens included the clear cell, papillary and chromophobe subtype in 65, 10 and 5 cases, respectively, and oncocytoma in 6. A total of 17 cases were positive for metastasis.

RESULTS

Median CXCR4 and 7, and SFD1-γ levels were increased twofold to tenfold. SDF1-α and β were unchanged or lower in clear cell renal cell carcinoma and papillary tumors than in normal tissue. Median SDF1-γ, IL-8, and CXCR4 and 7 were increased threefold to fortyfold in chromophobe tumors compared to oncocytoma. CXCR4 and 7 were increased in tumors less than 4 cm (mean 3,057 ± 2,230 and 806 ± 691) compared to oncocytoma (336 ± 325 and 201 ± 281, respectively, p ≤0.016). On multivariate analysis CXCR4 (p = 0.01), CXCR7 (p = 0.02) and SDF1-β (p = 0.005) were independently associated with metastasis. Combined CXCR7 plus SDF1-α and CXCR7 plus IL-8 markers showed the highest sensitivity (71% to 81%) and specificity (75% to 80%) of all individual or combined markers.

CONCLUSIONS

Chemokines and chemokine receptors differentiate renal cell carcinoma and oncocytoma. Combined SDF1-α plus CXCR7 and IL-8 plus CXCR7 markers have about 80% accuracy for predicting renal cell carcinoma metastasis.