Prognostic significance of stromal versican expression in human endometrial cancer

Hyaluronic Acid Interacting Molecules Mediated Crosstalk between Cancer Cells and Microenvironment from Primary Tumour to Distant Metastasis

Hyaluronic acid (HA) is a prominent component of the extracellular matrix, and its interactions with HA-interacting molecules (HAIMs) play a critical role in cancer development and disease progression. This review explores the multifaceted role of HAIMs in the context of cancer, focusing on their influence on disease progression by dissecting relevant cellular and molecular mechanisms in tumour cells and the tumour microenvironment. Cancer progression can be profoundly affected by the interactions between HA and HAIMs. They modulate critical processes such as cell adhesion, migration, invasion, and proliferation. The TME serves as a dynamic platform in which HAIMs contribute to the formation of a unique niche. The resulting changes in HA composition profoundly influence the biophysical properties of the TME. These modifications in the TME, in conjunction with HAIMs, impact angiogenesis, immune cell recruitment, and immune evasion. Therefore, understanding the intricate interplay between HAIMs and HA within the cancer context is essential for developing novel therapeutic strategies. Targeting these interactions offers promising avenues for cancer treatment, as they hold the potential to disrupt critical aspects of disease progression and the TME. Further research in this field is imperative for advancing our knowledge and the treatment of cancer.

Determination of Versikine Levels by Enzyme-Linked Immunosorbent Assay (ELISA)

The proteoglycan versican plays multiple roles in cancer progression, from promoting cell invasion and proliferation to evasion of immune surveillance. Metalloproteinases of the A Disintegrin and Metalloproteinase with Thrombospondin-like motif (ADAMTS) family cleave versican at a specific Glu-Ala bond, thus releasing a bioactive fragment named versikine, whose biological function, still not entirely revealed, seems that of antagonizing the effects of the parental molecule. Here we describe an enzyme-linked immunosorbent assay (ELISA) that specifically detects versikine in media, pure component systems, and biological fluids using neoepitope antibodies. Such antibodies recognize their target proteolytic fragment but not the intact, parental molecule. Versikine fragments are captured by neoepitope antibodies and detected by antibodies directed against its N-terminal globular (G1) domain. The method here described can therefore be used to measure ADAMTS versicanase activity and provides a quantitative alternative to immunoblotting.

Versican Secreted by Cancer-Associated Fibroblasts is a Poor Prognostic Factor in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is highly recurrent. Cancer-associated fibroblasts (CAFs), a major component of the tumor microenvironment, promote malignancy; however, the mechanisms underlying their actions are obscure. We aimed to identify CAF-specific proteins in HCC and determine whether they could be potential therapeutic targets.

METHODS

Using comprehensive proteomic analysis of CAFs and noncancerous fibroblasts (NFs) primary-cultured from resected HCC specimens from the same patients, CAF-specific proteins were identified. Immunohistochemistry for versican (VCAN) was performed on cancerous tissues obtained from 239 patients with HCC. Conditioned medium from CAFs transfected with siRNA for VCAN was analyzed in vitro.

RESULTS

CAFs significantly promoted HCC cell proliferation, migration, and invasion (p < 0.01, 0.01, and 0.01, respectively) compared with NFs. VCAN was upregulated in CAFs, and its stromal level correlated with poor differentiation (p = 0.009) and positive vascular invasion (p = 0.003). Stromal VCAN level was also associated with significantly lower overall (p = 0.002) and relapse-free (p < 0.001) survival rates. It also independently predicted prognosis and recurrence. VCAN-knockdown CAFs significantly suppressed HCC cell migration and invasion compared with negative control.

CONCLUSIONS

VCAN secreted from CAFs promoted malignant transformation of HCC cells and has potential as a new therapeutic target in HCC.

Targeting Versican as a Potential Immunotherapeutic Strategy in the Treatment of Cancer

A growing body of literature links events associated with the progression and severity of immunity and inflammatory disease with the composition of the tissue extracellular matrix as defined by the matrisome. One protein in the matrisome that is common to many inflammatory diseases is the large proteoglycan versican, whose varied function is achieved through multiple isoforms and post-translational modifications of glycosaminoglycan structures. In cancer, increased levels of versican are associated with immune cell phenotype, disease prognosis and failure to respond to treatment. Whether these associations between versican expression and tumour immunity are the result of a direct role in the pathogenesis of tumours is not clear. In this review, we have focused on the role of versican in the immune response as it relates to tumour progression, with the aim of determining whether our current understanding of the immunobiology of versican warrants further study as a cancer immunotherapy target.

Identification of Hub Genes Associated with the Pathogenesis of Intracranial Aneurysm via Integrated Bioinformatics Analysis

BACKGROUND

At present, the pathogenesis of intracranial aneurysms (IA) remains unclear, which significantly hinders the development of novel strategies for the clinical treatment. In this study, bioinformatics methods were used to identify the potential hub genes and pathways associated with the pathogenesis of IA.

METHODS

The gene expression datasets of patients with intracranial aneurysm were downloaded from the Gene Expression Database (GEO), and the different data sets were integrated by the robust rank aggregation (RRA) method to identify the differentially expressed genes between patients with intracranial aneurysm and the controls. The functional enrichment analyses of the significant differentially expressed genes (DEGs) were performed and the protein-protein interaction (PPI) network was constructed; thereafter, the hub genes were screened by cytoHubba plug-in of Cytoscape, and finally sequencing dataset GSE122897 was used to verify the hub genes.

RESULTS

The GSE15629, GSE75436, GSE26969, and GSE6551 expression profiles have been included in this study, including 34 intracranial aneurysm samples and 26 control samples. The four datasets obtained 136 significant DEGs (45 up-regulated, 91 down-regulated). Enrichment analysis showed that the extracellular matrix structural constituent and the ECM-receptor interaction were closely related to the occurrence of IA. It was finally determined that eight hub genes associated with the development of IA, including VCAN, COL1A1, COL11A1, COL5A1, COL5A2, POSTN, THBS2, and CDH2.

CONCLUSION

The discovery of potential hub genes and pathways could enhance the understanding of the molecular mechanisms associated with the development of IA. These hub genes may be potential therapeutic targets for the management and new biomarker for the diagnosis of IA.

Stromal expression of cancer-associated fibroblast-related molecules, versican and lumican, is strongly associated with worse relapse-free and overall survival times in patients with esophageal squamous cell carcinoma

Cancer-associated fibroblasts (CAFs) in the tumor microenvironment play an essential role in the tumor progression of esophageal squamous cell carcinoma (ESCC). The present study aimed to investigate the expression of CAF-related molecules, versican, periostin and lumican, in cancer stroma, to provide prognostic stratification for patients with ESCC after surgery. A total of 106 patients with ESCC who underwent curative esophagectomy without preoperative chemotherapy or radiotherapy were enrolled. The expression of CAF-related stromal proteins, including versican, periostin and lumican, was examined using immunohistochemistry, and the prognostic value was assessed by Kaplan-Meier survival analysis, and univariate and multivariate Cox regression models. The expression of versican, periostin and lumican was found specifically in the stromal component of ESCC. Kaplan-Meier analysis demonstrated that, compared with a low expression level, a high expression level of versican, periostin or lumican in the cancer stroma was significantly associated with worse relapse-free survival (RFS) and overall survival times in patients with ESCC. The prognostic values of stromal versican and lumican remained significant in a stratified analysis of stage I patients. Moreover, univariate and multivariate analysis revealed that high stromal versican or lumican expression was an independent prognostic factor for RFS in the patients. The present study demonstrated that CAF-related molecules, including versican, periostin and lumican, were expressed in the stroma of ESCC, and that stromal expression of versican and lumican in particular may have clinical utility as a prognostic biomarker for poor RFS in postoperative patients with ESCC.

PSGL-1 Immune Checkpoint Inhibition for CD4+ T Cell Cancer Immunotherapy

Immune checkpoint inhibition targeting T cells has shown tremendous promise in the treatment of many cancer types and are now standard therapies for patients. While standard therapies have focused on PD-1 and CTLA-4 blockade, additional immune checkpoints have shown promise in promoting anti-tumor immunity. PSGL-1, primarily known for its role in cellular migration, has also been shown to function as a negative regulator of CD4+ T cells in numerous disease settings including cancer. PSGL-1 is highly expressed on T cells and can engage numerous ligands that impact signaling pathways, which may modulate CD4+ T cell differentiation and function. PSGL-1 engagement in the tumor microenvironment may promote CD4+ T cell exhaustion pathways that favor tumor growth. Here we highlight that blocking the PSGL-1 pathway on CD4+ T cells may represent a new cancer therapy approach to eradicate tumors.

Carcinoma origin dictates differential skewing of monocyte function

Macrophages are versatile cells, which phenotype is profoundly influenced by their environment. Pro-inflammatory classically activated or M1 macrophages, and anti-inflammatory alternatively-activated or M2 macrophages represent two extremes of a continuum of functional states. Consequently, macrophages that are present in tumors can exert tumor-promoting and tumor-suppressing activity, depending on the tumor milieu. In this study we investigated how human monocytes-the precursors of macrophages-are influenced by carcinoma cells of different origin. We demonstrate that monocytes, stimulated with breast cancer supernatant, showed increased expression of interleukin (IL)-10, IL-8 and chemokines CCL17 and CCL22, which are associated with an alternatively-activated phenotype. By contrast, monocytes that were cultured in supernatants of colon cancer cells produced more pro-inflammatory cytokines (e.g., IL-12 and TNFα) and reactive oxygen species. Secretome analysis revealed differential secretion of proteins by colon and breast cancer cell lines, of which the proteoglycan versican was exclusively secreted by colon carcinoma cell lines. Reducing active versican by blocking with monoclonal antibodies or shRNA diminished pro-inflammatory cytokine production by monocytes. Thus, colon carcinoma cells polarize monocytes toward a more classically-activated anti-tumorigenic phenotype, whereas breast carcinomas predispose monocytes toward an alternatively activated phenotype. Interestingly, presence of macrophages in breast or colon carcinomas correlates with poor or good prognosis in patients, respectively. The observed discrepancy in macrophage activation by either colon or breast carcinoma cells may therefore explain the dichotomy between patient prognosis and macrophage presence in these different tumors. Designing new therapies, directing development of monocytes toward M1 activated tumor macrophages in cancer patients, may have great clinical benefits.

High expression of VCAN is an independent predictor of poor prognosis in gastric cancer

Objective

Methods

Results

Conclusion

Proteoglycans as Mediators of Cancer Tissue Mechanics

Proteoglycans are a diverse group of molecules which are characterized by a central protein backbone that is decorated with a variety of linear sulfated glycosaminoglycan side chains. Proteoglycans contribute significantly to the biochemical and mechanical properties of the interstitial extracellular matrix where they modulate cellular behavior by engaging transmembrane receptors. Proteoglycans also comprise a major component of the cellular glycocalyx to influence transmembrane receptor structure/function and mechanosignaling. Through their ability to initiate biochemical and mechanosignaling in cells, proteoglycans elicit profound effects on proliferation, adhesion and migration. Pathologies including cancer and cardiovascular disease are characterized by perturbed expression of proteoglycans where they compromise cell and tissue behavior by stiffening the extracellular matrix and increasing the bulkiness of the glycocalyx. Increasing evidence indicates that a bulky glycocalyx and proteoglycan-enriched extracellular matrix promote malignant transformation, increase cancer aggression and alter anti-tumor therapy response. In this review, we focus on the contribution of proteoglycans to mechanobiology in the context of normal and transformed tissues. We discuss the significance of proteoglycans for therapy response, and the current experimental strategies that target proteoglycans to sensitize cancer cells to treatment.

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.

Collagen triple helix repeat containing 1 promotes endometrial cancer cell migration by activating the focal adhesion kinase signaling pathway

Metastasis of endometrial cancer (EC) is known to be the major cause of relapse and death of patients. However, the mechanisms of this process are not well understood. Focal adhesion kinase (FAK) is known for its essential role in integrin signaling and is highly expressed in many human tumors. FAK also plays important roles in a variety of cellular processes. Collagen triple helix repeat containing 1 (CTHRC1) is a secreted protein that has been detected in many human solid cancers. In the present study, CTHRC1 was found to be highly expressed in EC tissues when compared with normal tissues. In addition, overexpression of CTHRC1 promoted the migration of EC cells in vitro. Recombinant CTHRC1 protein also promoted the migration of EC cells in vitro. The results of the present study suggested that CTHRC1 mediated EC cell migration via the FAK signaling pathway. Taken together, these data indicated that CTHRC1 and the FAK signaling pathway may be potential therapeutic targets for EC metastasis treatment.

Versican and Versican-matrikines in Cancer Progression, Inflammation, and Immunity

Versican is an extracellular matrix proteoglycan with key roles in multiple facets of cancer development, ranging from proliferative signaling, evasion of growth-suppressor pathways, regulation of cell death, promotion of neoangiogenesis, and tissue invasion and metastasis. Multiple lines of evidence implicate versican and its bioactive proteolytic fragments (matrikines) in the regulation of cancer inflammation and antitumor immune responses. The understanding of the dynamics of versican deposition/accumulation and its proteolytic turnover holds potential for the development of novel immune biomarkers as well as approaches to reset the immune thermostat of tumors, thus promoting efficacy of modern immunotherapies. This article summarizes work from several laboratories, including ours, on the role of this central matrix proteoglycan in tumor progression as well as tumor-immune cell cross-talk.

Uncovering Potential Roles of Differentially Expressed Genes, Upstream Regulators, and Canonical Pathways in Endometriosis Using an In Silico Genomics Approach

Endometriosis is characterized by ectopic endometrial tissue implantation, mostly within the peritoneum, and affects women in their reproductive age. Studies have been done to clarify its etiology, but the precise molecular mechanisms and pathophysiology remain unclear. We downloaded genome-wide mRNA expression and clinicopathological data of endometriosis patients and controls from NCBI’s Gene Expression Omnibus, after a systematic search of multiple independent studies comprising 156 endometriosis patients and 118 controls to identify causative genes, risk factors, and potential diagnostic/therapeutic biomarkers. Comprehensive gene expression meta-analysis, pathway analysis, and gene ontology analysis was done using a bioinformatics-based approach. We identified 1590 unique differentially expressed genes (129 upregulated and 1461 downregulated) mapped by IPA as biologically relevant. The top upregulated genes were FOS, EGR1, ZFP36, JUNB, APOD, CST1, GPX3, and PER1, and the top downregulated ones were DIO2, CPM, OLFM4, PALLD, BAG5, TOP2A, PKP4, CDC20B, and SNTN. The most perturbed canonical pathways were mitotic roles of Polo-like kinase, role of Checkpoint kinase proteins in cell cycle checkpoint control, and ATM signaling. Protein–protein interaction analysis showed a strong network association among FOS, EGR1, ZFP36, and JUNB. These findings provide a thorough understanding of the molecular mechanism of endometriosis, identified biomarkers, and represent a step towards the future development of novel diagnostic and therapeutic options.

Versican-A Critical Extracellular Matrix Regulator of Immunity and Inflammation

The extracellular matrix (ECM) proteoglycan, versican increases along with other ECM versican binding molecules such as hyaluronan, tumor necrosis factor stimulated gene-6 (TSG-6), and inter alpha trypsin inhibitor (IαI) during inflammation in a number of different diseases such as cardiovascular and lung disease, autoimmune diseases, and several different cancers. These interactions form stable scaffolds which can act as "landing strips" for inflammatory cells as they invade tissue from the circulation. The increase in versican is often coincident with the invasion of leukocytes early in the inflammatory process. Versican interacts with inflammatory cells either indirectly via hyaluronan or directly via receptors such as CD44, P-selectin glycoprotein ligand-1 (PSGL-1), and toll-like receptors (TLRs) present on the surface of immune and non-immune cells. These interactions activate signaling pathways that promote the synthesis and secretion of inflammatory cytokines such as TNFα, IL-6, and NFκB. Versican also influences inflammation by interacting with a variety of growth factors and cytokines involved in regulating inflammation thereby influencing their bioavailability and bioactivity. Versican is produced by multiple cell types involved in the inflammatory process. Conditional total knockout of versican in a mouse model of lung inflammation demonstrated significant reduction in leukocyte invasion into the lung and reduced inflammatory cytokine expression. While versican produced by stromal cells tends to be pro-inflammatory, versican expressed by myeloid cells can create anti-inflammatory and immunosuppressive microenvironments. Inflammation in the tumor microenvironment often contains elevated levels of versican. Perturbing the accumulation of versican in tumors can inhibit inflammation and tumor progression in some cancers. Thus versican, as a component of the ECM impacts immunity and inflammation through regulating immune cell trafficking and activation. Versican is emerging as a potential target in the control of inflammation in a number of different diseases.

Versican in the Tumor Microenvironment

Versican is an extracellular matrix proteoglycan with nonredundant roles in diverse biological and cellular processes, ranging from embryonic development to adult inflammation and cancer. Versican is essential for cardiovascular morphogenesis, neural crest migration, and skeletal development during embryogenesis. In the adult, versican acts as an inflammation "amplifier" and regulator of immune cell activation and cytokine production. Increased versican expression has been observed in a wide range of malignant tumors and has been associated with poor patient outcomes. The main sources of versican production in the tumor microenvironment include accessory cells (myeloid cells and stromal components) and, in some contexts, the tumor cells themselves. Versican has been implicated in several classical hallmarks of cancer such as proliferative signaling, evasion of growth suppressor signaling, resistance to cell death, angiogenesis, and tissue invasion and metastasis. More recently, versican has been implicated in escape from tumor immune surveillance, e.g., through dendritic cell dysfunction. Versican's multiple contributions to benign and malignant biological processes are further diversified through the generation of versican-derived bioactive proteolytic fragments (matrikines), with versikine being the most studied to date. Versican and versican-derived matrikines hold promise as targets in the management of inflammatory and malignant conditions as well as in the development of novel predictive and prognostic biomarkers.

VersicanV1 promotes proliferation and metastasis of hepatocellular carcinoma through the activation of EGFR-PI3K-AKT pathway

Versican has been reported to participate in carcinogenesis in several malignant tumors. However, the accurate role of VersicanV1, a predominant isoform of Versican in liver, remains an enigma in hepatocellular carcinoma (HCC). The expression of VersicanV1 in HCC tissues and adjacent tissues was detected by Reverse Transcription-Polymerase Chain Reaction (RT-PCR), Western Blot (WB) and inmumohistochemistry (IHC). Gain and loss of function assays were performed to examine the role of VersicanV1 in proliferation and metastasis of HCC. Measurement of oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in vitro and PET-CT (positron emission tomography/computed tomography) analysis in vivo were applied to evaluate the effects of VersicanV1 on glycolysis. RNA sequencing, Co-IP (Co-immunoprecipitation) and MS (mass spectrometry) were utilized to investigate the molecular mechanisms. Our current study reveals that VersicanV1, regulated by direct interaction with Linc01225, is significantly upregulated in HCC tissues and correlates with poor prognosis. Both in vitro and in vivo experiments show that knockdown of VersicanV1 in HCC cells attenuates cancer cells malignancy. Further studies identify the positive role of VersicanV1 in aerobic glycolysis. Mechanistic investigation discovers the activation of EGFR-PI3K-AKT pathway in HCC cells expressing high VersicanV1. Moreover, EGF-like motif is indispensable for VersicanV1 to promote Warburg effect of HCC cells and subsequently, proliferation, invasion, and metastasis ability via activation of EGFR-PI3K-AKT axis. In sum, our research highlights a novel role of VersicanV1 in the progression of HCC, suggesting that VersicanV1 is an indicator for prognosis and a potential therapeutic target of HCC.

Stromal Versican Regulates Tumor Growth by Promoting Angiogenesis

The proteoglycan versican is implicated in growth and metastases of several cancers. Here we investigated a potential contribution of stromal versican to tumor growth and angiogenesis. We initially determined versican expression by several cancer cell lines. Among these, MDA-MB231 and B16F10 had none to minimal expression in contrast to Lewis lung carcinoma (LLC). Notably, tumors arising from these cell lines had higher versican levels than the cell lines themselves suggesting a contribution from the host-derived tumor stroma. In LLC-derived tumors, both the tumor and stroma expressed versican at high levels. Thus, tumor stroma can make a significant contribution to tumor versican content. Versican localized preferentially to the vicinity of tumor vasculature and macrophages in the tumor. However, an ADAMTS protease-generated versican fragment uniquely localized to vascular endothelium. To specifically determine the impact of host/stroma-derived versican we therefore compared growth of tumors from B16F10 cells, which produced littleversican, in Vcan ^hdf/+ mice and wild-type littermates. Tumors in Vcan ^hdf/+ mice had reduced growth with a lower capillary density and accumulation of capillaries at the tumor periphery. These findings illustrate the variability of tumor cell line expression of versican, and demonstrate that versican is consistently contributed by the stromal tissue, where it contributes to tumor angiogenesis.

Interleukin-17A promotes tongue squamous cell carcinoma metastasis through activating miR-23b/versican pathway

Interleukin-17A (IL-17A), a proinflammatory cytokine mainly produced by T helper 17 cells, exerts protumor or antitumor effects in different cancer entities. However, the exact role of IL-17A in carcinogenesis and progression of tongue squamous cell carcinoma (TSCC) remains unclear. Here, we found that the levels of IL-17A in serum and tumor samples were significantly increased in TSCC patients and positively correlated with tumor metastasis and clinical stage. Besides, IL-17A enhanced cell migration and invasion in SCC15, a TSCC cell line. Furthermore, IL-17A inversely correlated with miR-23b expression in TSCC specimens. In vitro, NF-κB inhibited miR-23b transcription by directly binding to its promoter region. IL-17A downregulated miR-23b expression via activating NF-κB signaling pathway characterized by increasing p65 expression in the nuclear and elevating the levels of p-IKKα and p-IκBα. Overexpression of miR-23b inhibited, whereas knockdown of miR-23b promoted migration and invasion abilities of SCC15 cells. Moreover, extracellular matrix protein versican was proved to be the direct target of miR-23b through luciferase assay. IL-17A increased versican levels in vitro and knockdown of versican by siRNA inhibited SCC15 cell migration and invasion. Taken together, these results reveal a novel mechanism that IL-17A in TSCC microenvironment promotes the migration and invasion of TSCC cells through targeting miR-23b/versican pathway.

Stromal VCAN expression as a potential prognostic biomarker for disease recurrence in stage II-III colon cancer

To develop prognostic biomarkers that can discriminate stage II-III colorectal cancer patients with high risk of postoperative recurrence, we conducted a genome-wide screening of relapse-related genes utilizing multiple microarray cohorts. Among differentially expressed genes between tumor and nontumor, we identified eight candidate genes associated with relapse in two datasets of stage II-III patients (n = 94 and 145, respectively, P < 0.05). Using datasets of laser-microdissected samples and FACS-purified cell populations, the localization of candidate genes, including COL4A2, COL4A1, VCAN and SERPINE1, were found predominantly in cancer stroma rather than epithelial components. Among those relapse-related stromal genes, VCAN mRNA, specifically expressed in cancer-associated fibroblasts, was further validated to be a prognostic factor in two additional independent datasets, consisting of 453 (P = 0.0334) and 89 (P = 0.0041) stage II-III patients. Furthermore, in our large set of formalin-fixed paraffin-embedded cohort (n = 338), VCAN protein was detected exclusively in cancer stroma by immunohistochemistry, demonstrating a stepwise increase of stromal VCAN from normal tissues through stage 0 to stage IV tumors. Stromal VCAN protein was associated with shorter relapse-free survival (RFS) in stage II-III colon cancer, independent of other clinical factors by multivariate analysis (P = 0.004). Stratified analyses revealed that stromal VCAN was a strong prognostic indicator particularly in stage II colon cancer (P = 0.0029). In all five analyzed cohorts, the expression of VCAN, in transcript or protein levels, was associated with poor RFS in stage II-III patients. We conclude that VCAN is a promising biomarker to identify stage II-III patients at high risk of relapse who may benefit from intensive postoperative management.

Expression of a hyaluronic acid-binding proteoglycan (versican) in the cynomolgus monkey eye

The expression of versican, a hyaluronic acid (HA)-binding protein, during the development and differentiation of the retina has been reported. In this study, we performed histochemical and immunohistological analysis of HA and versican from the ciliary body to the retina in cynomolgus monkey eyes. Paraffin-embedded sections of cynomolgus monkey eyes, including from the ciliary body to the macular region, were prepared. The distribution of versican and HA was examined by histochemical and immunohistochemical methods. The sites of HA expression and versican expression in the eye specimens were similar. Expression of HA and versican was observed in the peripheral retina and ciliary body, but not from the macular region to the mid-periphery of the retina. Versican was strongly expressed in the ciliary body, particularly in the non-pigmented ciliary epithelium. Expression in the retina from the periphery to posterior pole gradually decreased. Versican is expressed from the ciliary body to the peripheral retina, but this expression decreases toward the posterior pole. This suggests a physiological function for versican in the peripheral retina.

Stromal derived factor-1 (SDF-1) and its receptors CXCR4 and CXCR7 in endometrial cancer patients

PURPOSE

One of the most important function of stromal derived factor-1 (SDF-1) and its receptors, is regulating the process of metastasis formation. The aim of our study was to investigate the correlation between SDF-1, CXCR4 and CXCR7 protein levels measured by immunohistochemistry with the clinicopathological features and the survival of endometrial cancer patients.

MATERIALS AND METHODS

92 patients aged 37-84 (mean 65.1±9.5) were enrolled to our study between January 2000 and December 2007. After the diagnosis of endometrial cancer, all women underwent total abdominal hysterectomy, with bilateral salpingoophorectomy and pelvic lymph node dissection. In all patients clinical stage (according to FIGO classification), histologic grade, myometrial invasion, lymph node and distant metastases were determined.Furthermore, the survival time was assessed. Immunohistochemical analyses of SDF-1, CXCR4 and CXCR7 were performed on archive formalin fixed paraffin embedded tissue sections.

RESULTS

Statistically significant correlations (p<0.01) were reported between SDF-1 and the clinical stage of disease, lymph node metastases, distant metastases, deep myometrial invasion (≥50%), cervical involvement, involvement of adnexa. Statistically significant correlation (p<0.01) was found between SDF-1 expression and the risk of the recurrence. Higher SDF-1 expression was associated with a higher risk of recurrence (p = 0.0001). The results of CXCR4 and CXCR7 expression didn't reveal any significant differences(p>0.05) between the proteins expression in the primary tumor cells and the clinicopathological features. Moreover, the Kaplan-Meier analyses demonstrated a stepwise impairment of cancer overall survival (OS) with increasing SDF-1 expression.

CONCLUSION

The important role of SDF-1 as a predictor of negative clinicopathological characteristics of a tumor suggests that the expression of this stromal factor should be included in the panel of accessory pathomorphological tests and could be helpful in establishing a more accurate prognosis in endometrial cancer patients.

Characterization of disease-associated N-linked glycoproteins

N-linked glycoproteins play important roles in biological processes, including cell-to-cell recognition, growth, differentiation, and programmed cell death. Specific N-linked glycoprotein changes are associated with disease progression and identification of these N-linked glycoproteins has potential for use in disease diagnosis, prognosis, and prediction of treatments. In this review, we summarize common strategies for N-linked glycoprotein characterization and applications of these strategies to identification of glycoprotein changes associated with disease states. We also review the N-linked glycoproteins altered in diseases such as breast cancer, lung cancer, and prostate cancer. Although assays for these glycoproteins have potential clinical utility, research is needed to translate these glycoproteins to clinical biomarkers.

Molecular profiling of multiple human cancers defines an inflammatory cancer-associated molecular pattern and uncovers KPNA2 as a uniform poor prognostic cancer marker

BACKGROUND

Immune evasion is one of the recognized hallmarks of cancer. Inflammatory responses to cancer can also contribute directly to oncogenesis. Since the immune system is hardwired to protect the host, there is a possibility that cancers, regardless of their histological origins, endow themselves with a common and shared inflammatory cancer-associated molecular pattern (iCAMP) to promote oncoinflammation. However, the definition of iCAMP has not been conceptually and experimentally investigated.

METHODS AND FINDINGS

Genome-wide cDNA expression data was analyzed for 221 normal and 324 cancer specimens from 7 cancer types: breast, prostate, lung, colon, gastric, oral and pancreatic. A total of 96 inflammatory genes with consistent dysregulation were identified, including 44 up-regulated and 52 down-regulated genes. Protein expression was confirmed by immunohistochemistry for some of these genes. The iCAMP contains proteins whose roles in cancer have been implicated and others which are yet to be appreciated. The clinical significance of many iCAMP genes was confirmed in multiple independent cohorts of colon and ovarian cancer patients. In both cases, better prognosis correlated strongly with high CXCL13 and low level of GREM1, LOX, TNFAIP6, CD36, and EDNRA. An "Inflammatory Gene Integrated Score" was further developed from the combination of 18 iCAMP genes in ovarian cancer, which predicted overall survival. Noticeably, as a selective nuclear import protein whose immuno-regulatory function just begins to emerge, karyopherin alpha 2 (KPNA2) is uniformly up-regulated across cancer types. For the first time, the cancer-specific up-regulation of KPNA2 and its clinical significance were verified by tissue microarray analysis in colon and head-neck cancers.

CONCLUSION

This work defines an inflammatory signature shared by seven epithelial cancer types and KPNA2 as a consistently up-regulated protein in cancer. Identification of iCAMP may not only serve as a novel biomarker for prognostication and individualized treatment of cancer, but also have significant biological implications.

Versican expression in canine carcinomas in benign mixed tumours: is there an association with clinical pathological factors, invasion and overall survival?

Background

Components of the extracellular matrix have been studied in an attempt to elucidate the mechanisms involved in the biological behaviour of tumours. The presence of the proteoglycan versican has been strongly associated with cancer development and progression. However, relationship between versican expression and clinical pathological factors and overall survival has not been previously studied in veterinary medicine. Carcinomas in benign mixed tumours (CBMTs) are one of the most common malignant tumours in female canines and can serve as models for studies of tumour progression. The aim of this study was to evaluate the expression of versican in in situ and invasive carcinomatous areas of canine CBMTs and to evaluate possible associations of versican expression with other classic prognostic factors and overall survival.

Results

Clinical staging; histological grade determination; immunohistochemical staining for versican, E-cadherin and Ki-67; and confirmation of invasion areas by staining for p63 and smooth muscle α-actin (α-SMA) were performed on 49 canine cases of CBMT. Tumour invasion was considered when suspicious Haematoxylin-Eosin (HE)-stained areas showed a total loss of α-SMA and p63 immunoreactivity. Versican immunoreactivity was less intense in the areas adjacent to the in situ carcinomatous regions, compared to invasive regions, which showed extensive and strong staining.

Conclusions

Our data reveal that in canine CBMTs, versican expression differs significantly between invasive and in situ areas, suggesting a role for this molecule in tumour progression. Although a direct relationship exists between versican and invasiveness, our results indicate that the isolated evaluation of this proteoglycan does not represent an independent prognostic factor in canine CBMTs.

Lumican and versican are associated with good outcome in stage II and III colon cancer

BACKGROUND

Tumor stroma plays an important role in the progression and metastasis of colon cancer. The glycoproteins versican and lumican are overexpressed in colon carcinomas and are associated with the formation of tumor stroma. The aim of the present study was to investigate the potential prognostic value of versican and lumican expression in the epithelial and stromal compartment of Union for International Cancer Control (UICC) stage II and III colon cancer.

METHODS

Clinicopathological data and tissue samples were collected from stage II (n = 226) and stage III (n = 160) colon cancer patients. Tissue microarrays were constructed with cores taken from both the center and the periphery of the tumor. These were immunohistochemically stained for lumican and versican. Expression levels were scored on digitized slides. Statistical evaluation was performed.

RESULTS

Versican expression by epithelial cells in the periphery of the tumor, i.e., near the invasive front, was correlated to a longer disease-free survival for the whole cohort (P = 0.01), stage III patients only (P = 0.01), stage III patients with microsatellite-instable tumors (P = 0.04), and stage III patients with microsatellite-stable tumors who did not receive adjuvant chemotherapy (P = 0.006). Lumican expression in epithelial cells overall in the tumor was correlated to a longer disease-specific survival in stage II patients (P = 0.05) and to a longer disease-free survival and disease-specific survival in microsatellite-stable stage II patients (P = 0.02 and P = 0.004).

CONCLUSIONS

Protein expression of versican and lumican predicted good clinical outcome for stage III and II colon cancer patients, respectively.

Inflammation amplification by Versican: the first mediator

The effects of inflammation may not always benefit the individual. Its amplifying nature represents a highly regulated biological program, and the inflammatory microenvironment is its essential component. Growing evidence suggests that the ECM (extracellular matrix) is important for the early steps of inflammation. Versican, a ubiquitous component of the ECM, contributes to the formation of the inflammatory response and is highly regulated by cytokines. Certain cytokines exert their initial effects on versican to alter the homeostasis of the inflammatory milieu, and inappropriate production of versican may promote the next inflammatory response. Therefore, versican could be the first step in the amplification of the inflammatory response, and ongoing research of this molecule may help to explain the pathogenesis of inflammation.

Altered expression of sialylated glycoproteins in breast cancer using hydrazide chemistry and mass spectrometry

Sialylation is one of the altered protein glycosylations associated with cancer development. The sialoglycoproteins in cancer cells, however, largely remain unidentified because of the lack of a method for quantitative analysis of sialoglycoproteins. This manuscript presents a high throughput method for quantitative analysis of N-linked sialoglycoproteins using conditional hydrazide chemistry, liquid chromatography, and tandem mass spectrometry. We further applied the sialoglycoproteomic method to the profiling of breast cancer tissues and compared findings with the results from the total glycoproteomic analysis using the original hydrazide chemistry method. We identified altered expression of sialoglycoproteins, as well as the total glycoprotein changes associated with breast cancer. Using lectin and Western blot analysis, we characterized one of the sialoglycoproteins, versican, and confirmed that versican was most sialylated and elevated in breast cancer. Furthermore, we showed that versican was detected in both cancer epithelial cells and peritumoral stromal cells using immunohistochemistry. Tissue microarray analysis revealed that epithelial expression of versican had significant relations to lymph node metastasis and pathological stages. This is the first quantitative sialoglycoproteomic and glycoproteomic analysis of breast cancer and noncancerous tissues. These findings present a significant addition of the method to the identification of altered expression of sialylated glycoproteins associated with breast cancer development.

Antithetic roles of proteoglycans in cancer

Proteoglycans (PGs), a family of complex post-translationally sculptured macromolecules, are fundamental regulators of most normal and aberrant cellular functions. The unparalleled structural-functional diversity of PGs endows them with the ability to serve as critical mediators of the tumor cells' interaction with the host microenvironment, while directly contributing to the organization and dynamic remodeling of this milieu. Despite their indisputable importance during embryonic development and in the adult organism, and their frequent dysregulation in tumor lesions, their precise involvement in tumorigenesis awaits a more decisive demonstration. Particularly challenging is to ascertain to what extent selected PGs may catalyze tumor progression and to what extent they may inhibit it, implying antithetic functions of individual PGs. Integrated efforts are needed to consolidate the routine use of PGs in the clinical monitoring of cancer patients and to broaden the exploitation of these macromolecules as therapeutic targets. Several PGs have the required attributes to be contemplated as effective antigens for immunotherapeutic approaches, while the tangible results obtained in recent clinical trials targeting the NG2/CSPG4 transmembrane PG urge further development of PG-based cancer treatment modalities.

Myeloid progenitor cells in the premetastatic lung promote metastases by inducing mesenchymal to epithelial transition

Tumors systemically initiate metastatic niches in distant target metastatic organs. These niches, composed of bone marrow-derived hematopoietic cells, provide permissive conditions for future metastases. However, the mechanisms by which these cells mediate outgrowth of metastatic tumor cells are not completely known. Using mouse models of spontaneous breast cancer, we show enhanced recruitment of bone marrow-derived CD11b(+)Gr1(+) myeloid progenitor cells in the premetastatic lungs. Gene expression profiling revealed that the myeloid cells from metastatic lungs express versican, an extracellular matrix proteoglycan. Notably, versican in metastatic lungs was mainly contributed by the CD11b(+)Ly6C(high) monocytic fraction of the myeloid cells and not the tumor cells or other stromal cells. Versican knockdown in the bone marrow significantly impaired lung metastases in vivo, without impacting their recruitment to the lungs or altering the immune microenvironment. Versican stimulated mesenchymal to epithelial transition of metastatic tumor cells by attenuating phospho-Smad2 levels, which resulted in elevated cell proliferation and accelerated metastases. Analysis of clinical specimens showed elevated versican expression within the metastatic lung of patients with breast cancer. Together, our findings suggest that selectively targeting tumor-elicited myeloid cells or versican represents a potential therapeutic strategy for combating metastatic disease.

Epithelial-mesenchymal transition, cancer stem cells and treatment resistance

Breast cancer relapse, in a large number of patients, after initial response to standard of care therapy warrants development of novel therapies against recurrent and metastatic cancer. Cancer stem cells (CSCs), present in breast tumors while being intrinsically resistant to conventional therapy, have the ability to self renew and cause tumor recurrence. The residual tumors after therapy, with dramatic enrichment of the CSCs, have all the hallmarks of epithelial- mesenchymal transition (EMT). This review will focus on the link between EMT, CSCs and treatment resistance, since a better understanding of these interactions will allow us to effectively target the residual population after therapy.

Does the expression of versican isoforms contribute to the pathogenesis of neurodegenerative diseases?

Classical neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's are most commonly seen in older persons. The incidence rate increases as life expectancy increases. Even though neuronal loss, neuronal death and accumulated toxic proteins are well investigated, the mechanism(s) of neurodegenerative disorders is not yet fully understood. Versican is a large extracellular matrix proteoglycan. Its isoforms are aberrantly expressed in central nervous system injuries. Diverse lines of evidence suggest that versican isoforms play a vital role in regulating neuronal differentiation, maturation, neurite outgrowth, and synaptic transmission. Some toxic proteins may be increased and less sensitive to degeneration due to the chondroitin sulfate (CS) chains of versicans. We propose that the patterns of versican V1 and V2 isoforms act as a fine-tuned mechanism for guiding the change of neural microenvironment, and the unbalanced expression of V1 and V2 isoforms may contribute to the pathogenesis of neurodegenerative diseases. The emergence of versican isoforms indicates that it may explain the pathogenesis of the common sporadic forms of complex diseases.

Versican expression is associated with tumor-infiltrating CD8-positive T cells and infiltration depth in cervical cancer

Cervical carcinoma is the second most frequent cancer type in women worldwide. Both inflammatory cells and stromal cells are important for tumor progression. Stromal cells produce growth factors and extracellular matrix and provide an adequate environment for angiogenesis. Versican, a member of the extracellular matrix, has been shown to have a role in tumor progression. The aim of this study was to investigate versican expression, and its association with tumor-infiltrating inflammatory cell subsets and with clinicopathological parameters in human cervical cancers. We have studied the expression of versican in 149 cervical cancers using immunohistochemistry and mRNA in situ hybridization. Versican was predominantly expressed in the stroma (myofibroblasts). Using quantitative real-time-PCR, V0 was found to be the most prominent isoform. High stromal versican expression was significantly associated with a low number of tumor-infiltrating T cells (P=0.018) and particularly a low number of CD8-positive T cells (cytotoxic T cells; P=0.002). Stromal versican expression was significantly higher in patients with an infiltration depth >14 mm (P=0.004) and in patients with parametrial invasion (P=0.044). Stromal versican expression was not associated with survival. Our results suggest that versican expression in the stromal compartment of cervical cancers results in reduced numbers of intraepithelial CD8-positive T cells and enhanced local invasion.

Podoplanin expression in cancerous stroma induces lymphangiogenesis and predicts lymphatic spread and patient survival

CONTEXT

Podoplanin is a mucin-type glycoprotein and a lymphatic endothelial marker. Immunohistochemical staining for podoplanin is currently used as a routine pathologic diagnosis tool in Japan to identify lymphatic invasion of cancer cells. Recent reports suggest that podoplanin and other proangiogenic molecules are expressed in stromal fibroblasts and myofibroblasts.

OBJECTIVE

To analyze the distribution of podoplanin expression in tumor stroma and its clinical and biologic significance.

DESIGN

We performed immunohistochemistry for podoplanin on tissue microarrays from 1350 cases of 14 common cancer types.

RESULTS

Two hundred eighty-seven of 662 cases (43%) showed podoplanin expression in the stromal cells within cancer nests. Stromal podoplanin expression in 14 common cancer types was significantly associated with tumor stage (P < .001), lymph node metastases (P < .001), lymphatic invasion (P  =  .02), and venous invasion (P < .001). The stromal cells positive for podoplanin were also positive for α-smooth muscle actin but negative for desmin, confirming a myofibroblasts phenotype. In contrast, myofibroblasts in inflammatory fibrotic lung diseases were podoplanin negative. Lymphatic vessel density was greater in the stromas with podoplanin expression than in the stroma lacking podoplanin-expressing stromal cells (P  =  .01). Survival data were available for non-small cell lung cancer. Stromal podoplanin expression was associated with poorer prognosis in adenocarcinoma (P < .001) and remains statistically significant after adjustment for sex, age, and stage (P  =  .01).

CONCLUSION

Our data indicate that podoplanin expression in stromal myofibroblasts may function as a proangiogenic biomarker and may serve as a predictive marker of lymphatic/vascular spread of cancer cells and a prognostic marker of patient survival.

DICER1 expression and outcomes in endometrioid endometrial adenocarcinoma

BACKGROUND

The objective of this study was to determine whether lower expression levels of DICER1 are associated with disease recurrence in patients with endometrioid endometrial cancer. The authors also explored DNA methylation and haploinsufficiency as potential mechanisms related to altered DICER1 expression in these tumors.

METHODS

DICER1 expression was assessed by quantitative polymerase chain reaction in a selected cohort of endometrioid endometrial tumors (N = 169). Loss of heterozygosity analyses were conducted using 2 single nucleotide polymorphisms, and combined bisulfate restriction analysis was used to assess methylation in the 5'-untranslated region of DICER1 in representative tumors. The correlations between DICER1 expression and clinicopathologic variables, including overall survival (OS) and disease-free survival (DFS), were assessed using nonparametric rank-sum tests and Cox proportional hazard models as appropriate. Survival distributions were described using the Kaplan-Meier method. A nested case-control analysis was conducted to confirm the association between transcript levels and disease recurrence.

RESULTS

Lower DICER1 expression (hazard ratio [HR], 1.36; 95% confidence interval [CI], 1.05-1.75; P = .02) and advanced disease stage (HR, 2.79; 95%CI, 1.59-4.90; P < .001) were associated with worse DFS. Three variables were associated significantly with reduced OS: age (HR, 1.04; 95%CI, 1.02-1.06; P < .0001), advanced disease stage (HR, 6.41; 95%CI, 3.57-11.52; P < .0001), and high tumor grade (HR, 2.96; 95%CI, 1.46-5.99; P = .003). Nested case-control analyses confirmed that there were lower DICER1 transcript levels in patients who had recurrent disease (P = .01). Deletion of DICER1 sequences was an infrequent event (5% of analyzed patients), and no methylation was observed in the 5' DICER1 regulatory region.

CONCLUSIONS

Lower DICER1 transcript levels were correlated with disease recurrence and worse DFS survival in patients with endometrioid endometrial cancer. The factors that influence DICER1 transcript levels in primary endometrial cancers remain unknown.

Progesterone induction of chondroitin sulfate proteoglycan aggrecan expression in human endometrial epithelial cells

Chondroitin sulfate (CS) is the most abundant glycosaminoglycan species in the human endometrium, but the expression profile of CS proteoglycans (PGs) in this mucosal tissue remains fully undetermined. In this study, we aimed to clarify the expression of CSPGs including aggrecan, neurocan, melanoma-associated CSPG, neuroglycan C, and brevican in the human cycling endometrium. By reverse transcription-polymerase chain reaction, the gene transcripts for aggrecan core protein were detected in all samples examined, while other CSPGs were not. Western blotting showed the immunoreactivity for aggrecan core protein at approximately 370 kDa size after enzymatic digestion of CS-A and CS-C side chains. The expression level of aggrecan core protein was significantly higher in the secretory phase than in the proliferative phase. The immunostaining for aggrecan was detected in the endometrial microvascular endothelium throughout the menstrual cycle. The immunostaining in the glandular epithelium was faint during the proliferative and early secretory phase, but distinct during the mid-to-late-secretory phase. Progesterone, but not 17β-estradiol, induced aggrecan core protein expression in cultured endometrial epithelial cells. The endometrial expression pattern of aggrecan was distinct from that of other known CSPGs, suggesting the unique role of this proteoglycan at the implantation site.

Proteoglycans in health and disease: novel roles for proteoglycans in malignancy and their pharmacological targeting

The expression of proteoglycans (PGs), essential macromolecules of the tumor microenvironment, is markedly altered during malignant transformation and tumor progression. Synthesis of stromal PGs is affected by factors secreted by cancer cells and the unique tumor-modified extracellular matrix may either facilitate or counteract the growth of solid tumors. The emerging theme is that this dual activity has intrinsic tissue specificity. Matrix-accumulated PGs, such as versican, perlecan and small leucine-rich PGs, affect cancer cell signaling, growth and survival, cell adhesion, migration and angiogenesis. Furthermore, expression of cell-surface-associated PGs, such as syndecans and glypicans, is also modulated in both tumor and stromal cells. Cell-surface-associated PGs bind various factors that are involved in cell signaling, thereby affecting cell proliferation, adhesion and motility. An important mechanism of action is offered by a proteolytic processing of cell-surface PGs known as ectodomain shedding of syndecans; this facilitates cancer and endothelial cell motility, protects matrix proteases and provides a chemotactic gradient of mitogens. However, syndecans on stromal cells may be important for stromal cell/cancer cell interplay and may promote stromal cell proliferation, migration and angiogenesis. Finally, abnormal PG expression in cancer and stromal cells may serve as a biomarker for tumor progression and patient survival. Enhanced understanding of the regulation of PG metabolism and the involvement of PGs in cancer may offer a novel approach to cancer therapy by targeting the tumor microenvironment. In this minireview, the implication of PGs in cancer development and progression, as well as their pharmacological targeting in malignancy, are presented and discussed.

Chemokines and Cancer Progression: A Qualitative Review on the Role of Stromal Cell-derived Factor 1-alpha and CXCR4 in Endometrial Cancer

The goal of this paper was to examine the literature related to stromal cell-derived factor 1-alpha (SDF-1alpha) and its receptor CXCR4 in endometrial cancer, as expression of these biomarkers has been implicated in an aggressive phenotype in other common epithelial cancers. We conducted a qualitative review of all published studies examining the role of SDF-1alpha/CXCR4 in endometrial cancer progression and prognosis. Pubmed and Ovid MEDLINE databases were searched in order to identify relevant studies for this qualitative review. Four studies have examined the role of the SDF-1alpha/CXCR4 pathway on endometrial cancer progression. The findings were contradictory; two studies reported an inverse association between overexpression and mortality while two studies reported overexpression to be associated with hallmarks of aggressive endometrial cancer. Expression of stromal-derived proteins can potentially serve as biomarkers of aggressive disease as well as biomarkers for remission monitoring, however the endometrial cancer literature has lagged behind in this area. Furthermore, the current research suffers from lack of comparability among different studies due to the utilization of different tools and lack of common outcome definitions. Future studies in this area should use clinically meaningful protein expression categories, widely accepted outcome definitions, and larger samples of patients. Finally, although standard immunohistochemistry is a mainstay in tumor marker studies, automated detection methods may be more suitable as they do not rely on subjective interpretation.

The biological role and regulation of versican levels in cancer

Increased expression of the proteoglycan, versican is strongly associated with poor outcome for many different cancers. Depending on the cancer type, versican is expressed by either the cancer cells themselves or by stromal cells surrounding the tumor. Versican plays diverse roles in cell adhesion, proliferation, migration and angiogenesis, all features of invasion and metastasis. These wide ranging functions have been attributed to the central glycosaminoglycan-binding region of versican, and to the N-(G1) and C-(G3) terminal globular domains which collectively interact with a large number of extracellular matrix and cell surface structural components. Here we review the recently identified mechanisms responsible for the regulation of versican expression and the biological roles that versican plays in cancer invasion and metastasis. The regulation of versican expression may represent one mechanism whereby cancer cells alter their surrounding microenvironment to facilitate the malignant growth and invasion of several tumor types. A greater understanding of the regulation of versican expression may contribute to the development of therapeutic methods to inhibit versican function and tumor invasion.

Beyond CA125: the coming of age of ovarian cancer biomarkers. Are we there yet?

Ovarian cancer (OC) is the fourth leading cause of cancer deaths among women in the United States, despite its relatively low incidence of 50 per 100,000. Even though advances in therapy have been made, the OC fatality-to-case ratio remains exceedingly high, due to the lack of accurate tools to diagnose early-stage disease when cure is still possible. The most studied marker for OC, CA125, is only expressed by 50-60% of patients with early stage disease. Large efforts have been deployed to identify novel serum markers, yet no single marker has emerged as a serious competitor for CA125. Various groups are investing in combination approaches to increase the diagnostic value of existing markers, but many markers may still lie in under-explored areas of ovarian cancer biology, such as tumor vasculature environment and post-translational modifications (glycomics).

Structure and regulation of the versican promoter: the versican promoter is regulated by AP-1 and TCF transcription factors in invasive human melanoma cells

Versican is a large chondroitin sulfate proteoglycan of the extracellular matrix that is involved in a variety of cellular processes. We showed previously that versican, which is overexpressed in cutaneous melanomas as well as in premalignant lesions, contributes to melanoma progression, favoring the detachment of cells and the metastatic dissemination. Here, we investigated the transcriptional regulation of the versican promoter in melanoma cell lines with different levels of biological aggressiveness and stages of differentiation. We show that versican promoter up-regulation accounts for the differential expression levels of mRNA and protein detected in the invasive SK-mel-131 human melanoma cells. The activity of the versican promoter increased 5-fold in these cells in comparison with that measured in non-invasive MeWo melanoma cells. Several transcriptional regulatory elements were identified in the proximal promoter, including AP-1, Sp1, AP-2, and two TCF-4 sites. We show that promoter activation is mediated by the ERK/MAPK and JNK signaling pathways acting on the AP-1 site, suggesting that BRAF mutation present in SK-mel-131 cells impinge upon the up-regulation of the versican gene through signaling elicited by the ERK/MAPK pathway. This is the first time the AP-1 transcription factor family has been shown to be related to the regulation of versican expression. Furthermore, deletion of the TCF-4 binding sites caused a 60% decrease in the promoter activity in SK-mel-131 cells. These results showing that AP-1 and TCF-4 binding sites are the main regulatory regions directing versican production provide new insights into versican promoter regulation during melanoma progression.

Prognostic significance of epithelial-mesenchymal and mesenchymal-epithelial transition protein expression in non-small cell lung cancer

PURPOSE

In carcinomas, invasive tumor growth is accompanied by desmoplastic stroma reaction and facilitated by epithelial-mesenchymal transition (EMT) of cancer cells. We investigated the prognostic significance of the EMT indicator proteins periostin and vimentin in comparison with versican, a putative indicator of the opposite mechanism mesenchymal-epithelial transition (MET), and to the desmoplasia proteins collagen and elastin in non-small cell lung cancer (NSCLC).

EXPERIMENTAL DESIGN

Tumor of 533 patients with surgically resected NSCLC was used for analysis of stromal and epithelial protein expression by immunohistochemistry (EMT-MET proteins) and Elastica van Gieson histochemical staining (collagen and elastin). A semiquantitative sum scoring system was done on three tissue microarrays.

RESULTS

Of the 533 patients, 48% had squamous cell carcinoma, 47% adenocarcinoma, and 5% adenosquamous carcinoma. High expression of periostin in either stroma or tumor epithelia, independently scored by two pathologists, correlated with male gender, higher stage, higher pT category, and larger tumor size, and in only stroma with tumor relapse. High expression of versican in either stroma or epithelia as well as of stromal collagen had fewer but concordant associations with advanced tumor and periostin, respectively. High expression of elastin was oppositely associated with less advanced disease. Associations of high vimentin were inconsistent (all P values < 0.05). High stromal periostin was found to be a prognostic factor for decreased progression-free survival on univariate analysis (P = 0.007).

CONCLUSIONS

Because up-regulation is frequently observed in the stromal and epithelial tumor compartment, EMT-MET indicator proteins may be integrated in progression models of NSCLC.

Molecular signatures associated with transformation and progression to breast cancer in the isogenic MCF10 model

Comparative microarray analyses provided insight into understanding transcript changes during cancer progression; however, a reproducible signature underlying breast carcinogenesis has yet to be little available. We utilized gene expression profiling to define molecular signatures associated with transformation and cancer progression in a series of isogenic human breast cancer cell lines including a normal, benign, noninvasive and invasive carcinoma. Clustering analysis revealed four distinct expression patterns based on upregulation or downregulation patterns. These profiles proved quite useful for describing breast cancer tumorigenesis and invasiveness. Downregulation of TNFSF7, S100A4, S100A7, S100A8, and S100A9 (calcium-binding protein family), and upregulation of kallikrein-5 and thrombospondin-1 were associated with transformation and progression of breast cancer cells. Importantly, downregulation of the genes was reversed by treatment with silencing inhibitors, implying the potential roles of epigenetic inactivation in breast carcinogenesis. Exogenous expressions of S100A8 and S100A9 inhibit growth in benign and noninvasive carcinoma cells, suggesting their negative role in cell proliferation. The data presented here may facilitate the identification and functional analyses of prognostic biomarkers for breast cancer.

Overlapping gene expression profiles of cell migration and tumor invasion in human bladder cancer identify metallothionein 1E and nicotinamide N-methyltransferase as novel regulators of cell migration

Cell migration is essential to cancer invasion and metastasis and is spatially and temporally integrated through transcriptionally dependent and independent mechanisms. As cell migration is studied in vitro, it is important to identify genes that both drive cell migration and are biologically relevant in promoting invasion and metastasis in patients with cancer. Here, gene expression profiling and a high-throughput cell migration system answers this question in human bladder cancer. In vitro migration rates of 40 microarray-profiled human bladder cancer cell lines were measured by radial migration assay. Genes whose expression was either directly or inversely associated with cell migration rate were identified and subsequently evaluated for their association with cancer stage in 61 patients. This analysis identified genes known to be associated with cell invasion such as versican, and novel ones, including metallothionein 1E (MT1E) and nicotinamide N-methyltransferase (NNMT), whose expression correlated positively with cancer cell migration and tumor stage. Using loss of function analysis, we show that MT1E and NNMT are necessary for cancer cell migration. These studies provide a general approach to identify the clinically relevant genes in cancer cell migration and mechanistically implicate two novel genes in this process in human bladder cancer.

Proteoglycans in the control of tumor growth and metastasis formation

Proteoglycans (PGs) as a whole, or when considering their GAG chains as single entities, are emerging as key regulators of tumor progression. Expectations on using them as putative prognostic markers and potential therapeutic targets are increasing coincidentally. Due to the multitude of biological roles that they may invest and the ample spectrum of cellular processes that they may control, we still need to learn better how they regulate phenomena such as intracellular signaling, proliferation, apoptosis, motility, and drug resistance. Depending on the type, their expression pattern, and the accessibility of their molecular ligands, PGs can either promote or inhibit tumorigenesis. The structural and functional diversity of PGs coupled with their ubiquitous abundance place them at the crossroads of many critical steps within the metastatic cascade. As this phenomenon is the pivotal factor for patient survivals, particular attention should be given to the understanding of how PGs govern metastasis formation.