Decorin deficiency promotes hepatic carcinogenesis

The importance of biglycan, decorin and TGF-1 levels in the diagnosis of non-small cell lung cancer

BACKGROUND

Despite Non-small cell lung cancer (NSCLC) ranks among the most deadly cancers worldwide, and currently, apart from a low percentage, targetable molecules have not been identified in its etiopathogenesis. The relationship between the proteoglycans decorin and biglycan, which are present in the extracellular matrix of cells, and transforming growth factor Beta-1 (TGF-B1), has been shown in many cancers. We investigated the significance of these molecules in NSCLC.

METHODS

Fasting serum levels of decorin, biglycan, and TGF-B1 were obtained from 48 newly diagnosed NSCLC patients and compared with those of 48 adult control subjects matched for age and demographics. Demographic data, baseline laboratory values, and ELISA results were compared between the groups.

RESULTS

The median age was 65(39-83) similar in both groups. There was no relation between demographic and clinical parameters and the levels of decorin, biglycan, and TGF-B1 in the NSCLC group. However, in comparison to the control group, NSCLC patients had significantly higher levels of biglycan (42.55 ± 27.40 vs. 24.38 ± 12.05 ng/mL, p= 0.026) and TGF-B1 (15.55 ± 9.16 vs. 10.07 ± 7.8 pg/mL, p= 0.001), while decorin levels were significantly lower (6.64 ± 1.92 vs. 10.28 ± 3.13 ng/mL, p= 0.002). In the multivariate regression analysis; Decorin < 8.13 ng/mL (OR, 10.96; 95% CI: 3.440-34.958), current smoking (OR, 3.81; 95% CI: 1.320-10.998), COPD (OR, 43.6; 95% CI: 2.082-913.081), and lower BMI (OR, 1.22; 95% CI: 1.070-1.405, p= 0.003) were identified as independent predictive markers for NSCLC diagnosis.

CONCLUSION

The decreased serum decorin level is an independent marker for NSCLC. Further studies are needed to investigate the prognostic significance of decorin on survival and its potential as a target in treatment.

Decorin suppresses tumor lymphangiogenesis: A mechanism to curtail cancer progression

The complex interplay between malignant cells and the cellular and molecular components of the tumor stroma is a key aspect of cancer growth and development. These tumor-host interactions are often affected by soluble bioactive molecules such as proteoglycans. Decorin, an archetypical small leucine-rich proteoglycan primarily expressed by stromal cells, affects cancer growth in its soluble form by interacting with several receptor tyrosine kinases (RTK). Overall, decorin leads to a context-dependent and protracted cessation of oncogenic RTK activity by attenuating their ability to drive a pro-survival program and to sustain a pro-angiogenic network. Through an unbiased transcriptomic analysis using deep RNAseq, we discovered that decorin downregulated a cluster of tumor-associated genes involved in lymphatic vessel development when systemically delivered to mice harboring breast carcinoma allografts. We found that Lyve1 and Podoplanin, two established markers of lymphatic vessels, were markedly suppressed at both the mRNA and protein levels and this suppression correlated with a significant reduction in tumor lymphatic vessels. We further discovered that soluble decorin, but not its homologous proteoglycan biglycan, inhibited lymphatic vessel sprouting in an ex vivo 3D model of lymphangiogenesis. Mechanistically, we found that decorin interacted with VEGFR3, the main lymphatic RTK, and its activity was required for the decorin-mediated block of lymphangiogenesis. Finally, we discovered that Lyve1 was in part degraded via decorin-evoked autophagy in a nutrient- and energy-independent manner. These findings implicate decorin as a new biological factor with anti-lymphangiogenic activity and provide a potential therapeutic agent for curtailing breast cancer growth and metastasis.

Small leucine rich proteoglycans: Biology, function and their therapeutic potential in the ocular surface

Small leucine rich proteoglycans (SLRPs) are the largest family of proteoglycans, with 18 members that are subdivided into five classes. SLRPs are small in size and can be present in tissues as glycosylated and non-glycosylated proteins, and the most studied SLRPs include decorin, biglycan, lumican, keratocan and fibromodulin. SLRPs specifically bind to collagen fibrils, regulating collagen fibrillogenesis and the biomechanical properties of tissues, and are expressed at particularly high levels in fibrous tissues, such as the cornea. However, SLRPs are also very active components of the ECM, interacting with numerous growth factors, cytokines and cell surface receptors. Therefore, SLRPs regulate major cellular processes and have a central role in major fundamental biological processes, such as maintaining corneal homeostasis and transparency and regulating corneal wound healing. Over the years, mutations and/or altered expression of SLRPs have been associated with various corneal diseases, such as congenital stromal corneal dystrophy and cornea plana. Recently, there has been great interest in harnessing the various functions of SLRPs for therapeutic purposes. In this comprehensive review, we describe the structural features and the related functions of SLRPs, and how these affect the therapeutic potential of SLRPs, with special emphasis on the use of SLRPs for treating ocular surface pathologies.

Ferroptosis in hepatocellular carcinoma: from bench to bedside

The most widespread type of liver cancer, HCC, is associated with disabled cellular death pathways. Despite therapeutic advancements, resistance to current systemic treatments (including sorafenib) compromises the prognosis of patients with HCC, driving the search for agents that might target novel cell death pathways. Ferroptosis, a form of iron-mediated nonapoptotic cell death, has gained considerable attention as a potential target for cancer therapy, especially in HCC. The role of ferroptosis in HCC is complex and diverse. On one hand, ferroptosis can contribute to the progression of HCC through its involvement in both acute and chronic liver conditions. In contrast, having ferroptosis affect HCC cells might be desirable. This review examines the role of ferroptosis in HCC from cellular, animal, and human perspectives while examining its mechanisms, regulation, biomarkers, and clinical implications.

HBx downregulated decorin and decorin-derived peptides inhibit the proliferation and tumorigenicity of hepatocellular carcinoma cells

Hepatitis B virus (HBV) is one of the important risk factors in inducing the occurrence and development of liver cancer, while the mechanism has not been fully clarified. In this study, we found decorin (DCN) was significantly reduced in HBV transgenic cell line HepG2-4D14 compared to HepG2. The data from hepatocellular carcinoma (HCC) patients indicated that the level of DCN mRNA was significantly lower in tumor tissues than healthy control and positively correlated with the survival of HCC patients. We revealed that HBV HBx can inhibit the transcription of DCN by blocking p53 activity. Functional analysis demonstrated that overexpression of DCN substantially inhibits the proliferation of HCC cells, while knockdown of DCN enhances the proliferation of HCC cells. It is known that DCN could competitively bind to c-Met to inhibit HGF/c-Met signaling pathway to inhibit the development of HCC. Therefore, we screened the novel antitumor peptides derived from DCN based on the sequence of DCN and the complex structure of HGF/c-Met with virtual screening and identified a set of DCN-derived peptides (DCN-Ps) which may competitively bind to c-Met. We found that 5 of peptides can reduce the proliferation and migration of HepG2 cells significantly. Among them, DCN-P#3 can inhibit the growth of HCC cells both in vitro and in vivo. In conclusion, we discovered that HBV HBx downregulates the expression of DCN, which in turn promotes the proliferation of hepatocytes and the development of HCC. We identified DCN-derived antitumor peptides which provides the candidates for developing novel drugs against HCC.

In Silico and In Vivo Evaluation of microRNA-181c-5p's Role in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a fatal disease, accounting for 75-85% of primary liver cancers. The conclusive research on miR-181c-5p's role in hepatocarcinogenesis, whether it has oncogenic effects or acts as a tumor repressor, is limited and fluctuating. Therefore, the current study aimed to elucidate the role of miR-181c-5p in HCC in silico and in vivo. The bioinformatics analysis of miR-181c-5p expression data in HCC using several databases strongly shed light on its involvement in HCC development, but also confirmed the fluctuating data around its role. miR-181c-5p was proven here to have an oncogenic role by increasing HepG2 cells' viability as confirmed by MTT analysis. In addition, miR-181c-5p was upregulated in the HCC positive control group and progressed the HCC development and malignant features by its forced expression in an HCC mouse model by targeted delivery using a LA-PAMAM polyplex. This is indicated by the cancerous gross and histological features, and the significant increase in liver function biomarkers. The functional enrichment bioinformatics analyses of miR-181c-5p-downregulated targets in HCC indicated that miR-181c-5p targets were significantly enriched in multiple pathways and biological processes involved in HCC development. Fbxl3, an example for miR-181c-5p potential targets, downregulation and its correlation with miR-181c-5p were validated by qPCR. In conclusion, miR-181c-5p is upregulated in HCC and has an oncogenic role enhancing HCC progression.

Decorin evokes reversible mitochondrial depolarization in carcinoma and vascular endothelial cells

Decorin, a small leucine-rich proteoglycan with multiple biological functions, is known to evoke autophagy and mitophagy in both endothelial and cancer cells. Here, we investigated the effects of soluble decorin on mitochondrial homeostasis using live cell imaging and ex vivo angiogenic assays. We discovered that decorin triggers mitochondrial depolarization in triple-negative breast carcinoma, HeLa, and endothelial cells. This bioactivity was mediated by the protein core in a time- and dose-dependent manner and was specific for decorin insofar as biglycan, the closest homolog, failed to trigger depolarization. Mechanistically, we found that the bioactivity of decorin to promote depolarization required the MET receptor and its tyrosine kinase. Moreover, two mitochondrial interacting proteins, mitostatin and mitofusin 2, were essential for downstream decorin effects. Finally, we found that decorin relied on the canonical mitochondrial permeability transition pore to trigger tumor cell mitochondrial depolarization. Collectively, our study implicates decorin as a soluble outside-in regulator of mitochondrial dynamics.

Identifying the EMT-related signature to stratify prognosis and evaluate the tumor microenvironment in lung adenocarcinoma

Background: Epithelial-mesenchymal transition (EMT) is a critical process in tumor invasion and metastasis. EMT has been shown to significantly influence the invasion, metastasis, and poor prognosis in lung adenocarcinoma (LUAD). This study aimed to develop a novel EMT-related prognostic model capable of predicting overall survival (OS) in patients with LUAD.

Methods: A total of 283 LUAD patients from TCGA RNA-seq dataset were assigned to a training cohort for model building, and 310 LUAD patients from GEO RNA-seq dataset were assigned to a validation cohort. EMT genes were acquired from MsigDB database and then prognosis-related EMT genes were identified by univariate Cox regression. Lasso regression was then performed to determine the genes and the corresponding variables to construct a prognosis risk model from the training cohort. Furthermore, characteristics of the tumor microenvironment (TME), mutation status and chemotherapy responses were analyzed to assess the differences between the two risk groups based on the prognostic model. In addition, RT-qPCR was employed to validate the expression patterns of the 6 genes derived from the risk model.

Results: A six-gene EMT signature (PMEPA1, LOXL2, PLOD2, MMP14, SPOCK1 and DCN) was successfully constructed and validated. The signature assigned the LUAD patients into high-risk and low-risk groups. In comparison with the low-risk group, patients in the high-risk group had a significantly lower survival rate. ROC curves and calibration curves for the risk model demonstrated reliable stratification and predictive ability. The risk model was robustly correlated with multiple TME characteristics. Besides, the data showed that patients in the low-risk group had more immune activities, higher stemness scores and cytolytic activity scores and higher TMB. In addition, RT-qPCR results revealed that PMEPA1, LOXL2, PLOD2, MMP14, and SPOCK1 were notably upregulated in LUAD tissues, while DCN was downregulated.

Conclusion: Our study successfully developed a novel EMT-related signature to predict prognosis of LUAD patients and guide treatment strategies. The six genes derived from the prediction signature might play a potential role in antitumor immunity and serve as promising therapeutic targets in LUAD.

The multifaceted role of Matricellular Proteins in health and cancer, as biomarkers and therapeutic targets

The extracellular matrix (ECM) is composed of a mesh of proteins, proteoglycans, growth factors, and other secretory components. It constitutes the tumor microenvironment along with the endothelial cells, cancer-associated fibroblasts, adipocytes, and immune cells. The proteins of ECM can be functionally classified as adhesive proteins and matricellular proteins (MCP). In the tumor milieu, the ECM plays a major role in tumorigenesis and therapeutic resistance. The current review encompasses thrombospondins, osteonectin, osteopontin, tenascin C, periostin, the CCN family, laminin, biglycan, decorin, mimecan, and galectins. The matrix metalloproteinases (MMPs) are also discussed as they are an integral part of the ECM with versatile functions in the tumor stroma. In this review, the role of these proteins in tumor initiation, growth, invasion and metastasis have been highlighted, with emphasis on their contribution to tumor therapeutic resistance. Further, their potential as biomarkers and therapeutic targets based on existing evidence are discussed. Owing to the recent advancements in protein targeting, the possibility of agents to modulate MCPs in cancer as therapeutic options are discussed.

Oncosuppressive roles of decorin through regulation of multiple receptors and diverse signaling pathways

Decorin is a stromal-derived prototype member of the small leucine-rich proteoglycan gene family. In addition to its functions as a regulator of collagen fibrillogenesis and TGF-β activity soluble decorin acts as a pan-receptor tyrosine kinase (RTK) inhibitor. Decorin binds to various RTKs including EGFR HER2 HGFR/Met VEGFR2 TLR and IGFR. Although the molecular mechanism for the action of decorin on these receptors is not entirely elucidated overall decorin evokes transient activation of these receptors with suppression of downstream signaling cascades culminating in growth inhibition followed by their physical downregulation via caveosomal internalization and degradation. In the case of Met decorin leads to decreased β-catenin signaling pathway and growth suppression. As most of these RTKs are responsible for providing a growth advantage to cancer cells the result of decorin treatment is oncosuppression. Another decorin-driven mechanism to restrict cancer growth and dissemination is by impeding angiogenesis via vascular endothelial growth factor receptor 2 (VEGFR2) and the concurrent activation of protracted endothelial cell autophagy. In this review we will dissect the multiple roles of decorin in cancer biology and its potential use as a next-generation protein-based adjuvant therapy to combat cancer.

Identification of Clinical and Tumor Microenvironment Characteristics of Hypoxia-Related Risk Signature in Lung Adenocarcinoma

Background: Lung cancer is the leading cause of cancer-related death globally. Hypoxia can suppress the activation of the tumor microenvironment (TME), which contributes to distant metastasis. However, the role of hypoxia-mediated TME in predicting the diagnosis and prognosis of lung adenocarcinoma (LUAD) patients remains unclear.

Methods: Both RNA and clinical data from the LUAD cohort were downloaded from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Both univariate and multivariate Cox regression analyses were used to further screen prognosis-related hypoxia gene clusters. Time-dependent receiver operation characteristic (ROC) curves were established to evaluate the predictive sensitivity and specificity of the hypoxia-related risk signature. The characterization of gene set enrichment analysis (GSEA) and TME immune cell infiltration were further explored to identify hypoxia-related immune infiltration.

Results: Eight hypoxia-related genes (LDHA, DCN, PGK1, PFKP, FBP1, LOX, ENO3, and CXCR4) were identified and established to construct a hypoxia-related risk signature. The high-risk group showed a poor overall survival compared to that of the low-risk group in the TCGA and GSE68465 cohorts (p < 0.0001). The AUCs for 1-, 3-, and 5-year overall survival were 0.736 vs. 0.741, 0.656 vs. 0.737, and 0.628 vs. 0.649, respectively. The high-risk group was associated with immunosuppression in the TME.

Conclusion: The hypoxia-related risk signature may represent an independent biomarker that can differentiate the characteristics of TME immune cell infiltration and predict the prognosis of LUAD.

Decorin Induces Cardiac Hypertrophy by Regulating the CaMKII/MEF-2 Signaling Pathway In Vivo

OBJECTIVE

Cardiac hypertrophy is an adaptive reaction of the heart against cardiac overloading, but continuous cardiac hypertrophy can lead to cardiac remodeling and heart failure. Cardiac hypertrophy is mostly considered reversible, and recent studies have indicated that decorin not only prevents cardiac fibrosis associated with hypertension, but also achieves therapeutic effects by blocking fibrosis-related signaling pathways. However, the mechanism of action of decorin remains unknown and unconfirmed.

METHODS

We determined the degree of myocardial hypertrophy by measuring the ratios of the heart weight/body weight and left ventricular weight/body weight, histological analysis and immunohistochemistry. Western blotting was performed to detect the expression levels of CaMKII, p-CaMKII and MEF-2 in the heart.

RESULTS

Our results confirmed that decorin can regulate the CaMKII/MEF-2 signaling pathway, with inhibition thereof being similar to that of decorin in reducing cardiac hypertrophy.

CONCLUSION

Taken together, the results of the present study showed that decorin induced cardiac hypertrophy by regulating the CaMKII/MEF-2 signaling pathway in vivo, revealing a new therapeutic approach for the prevention of cardiac hypertrophy.

Cancer-Associated Fibroblasts Promote Vascular Invasion of Hepatocellular Carcinoma via Downregulating Decorin-integrin β1 Signaling

Hepatocellular carcinoma (HCC) is a common malignancy worldwide, and the high ratio of recurrence and metastasis remains the main cause of its poor prognosis. Vascular invasion of HCC includes microvascular invasion (MVI) and portal vein tumor thrombosis (PVTT) and is regarded as a common roadmap of intrahepatic metastasis in HCC. However, the molecular mechanism underlying vascular invasion of HCC is largely unknown. Here, we analyzed the transcriptomes of primary tumors, PVTT tissues, and tumor tissues with or without MVI. We found that extracellular matrix-related pathways were involved in vascular invasion of HCC and that decorin secreted by cancer-associated fibroblasts was gradually downregulated from normal to tumor tissues and more so in PVTT tissues. We also established that low-level decorin expression is an independent risk factor for MVI and it is associated with a poor prognosis. Decorin downregulated integrin β1 and consequently inhibited HCC cell invasion and migration in vitro. Co-staining DCN and integrin β1 revealed that DCN dynamically regulated integrin β1 protein expression. Integrin β1 knockdown significantly inhibited HCC invasion and migration, and decorin combined with such knockdown synergistically augmented the anti-metastatic effects. Co-IP assay confirmed the direct interaction of decorin with integrin β1. Our findings showed that targeting cancer-associated fibroblast-related decorin is not only a promising strategy for inhibiting HCC vascular invasion and metastasis but also provides insight into the clinical treatment of patients with PVTT.

Bone marrow plasma level of decorin may be associated with improved treatment outcomes in a subset of multiple myeloma patients

BACKGROUND/PURPOSE

Decorin is a small leucine-rich proteoglycan rich in extracellular matrix with potential antitumor activity. However, the role of decorin in hematological malignancies remains unclear, especially in the case of multiple myeloma (MM), a bone marrow (BM) stroma-dependent plasma cell neoplasm.

METHODS

We measured decorin levels in BM plasma samples from 270 patients with newly diagnosed MM (NDMM) using enzyme-linked immunosorbent assays.

RESULTS

Patients were divided into high decorin (H-DCN, > 18.99 ng/mL) and low decorin (L-DCN <9.76 ng/mL) groups. Patients in the H-DCN group had more advanced-stage disease, including more osteolysis terms of higher levels of C-terminal telopeptides of type I collagen (0.69 ± 0.55 vs. 0.49 ± 0.36 ng/mL; P = 0.028), than those in the L-DCN group. Decorin levels correlated positively with hepatocyte growth factor (HGF) levels in BM plasma samples from NDMM patients (Pearson correlation coefficient, 0.226; P < 0.001). Patients with low HGF (<0.79 ng/mL) but high decorin levels (≥12.95 ng/mL) had a higher treatment response rate (90.5% vs. 54.5%, respectively; P = 0.015) and improved overall survival (not reached vs. 53 months; P = 0.0148) than those with lower decorin levels (<12.95 ng/mL). Multivariate analysis confirmed that a high decorin level was an independent predictive factor for treatment response and survival in patients with low HGF levels.

CONCLUSION

Our findings suggest that decorin may exert protective effects in this subset of MM patients.

Identification of prognostic biomarkers associated with the occurrence of portal vein tumor thrombus in hepatocellular carcinoma

The occurrence of portal vein tumor thrombus (PVTT) is strongly correlated to the staging and poor prognosis of hepatocellular carcinoma (HCC) patients. However, the mechanisms of PVTT formation remain unclear. This study aimed to investigate differentially expressed genes (DEGs) between primary tumor (PT) and PVTT tissues and comprehensively explored the underlying mechanisms of PVTT formation. The DEGs between PT and paired PVTT tissues were analyzed using transcriptional data from the Gene Expression Omnibus (GEO) database. The expression, clinical relevance, prognostic significance, genetic alternations, DNA methylation, correlations with immune infiltration, co-expression correlations, and functional enrichment analysis of the DEGs were explored using multiple databases. As result, 12 DEGs were commonly down-expressed in PVTT compared with PT tissues among three datasets. The expression of DCN, CCL21, IGJ, CXCL14, FCN3, LAMA2, and NPY1R was progressively decreased from normal liver, PT, to PVTT tissues, whose up-expression associated with favorable survivals of HCC patients. The genetic alternations and DNA methylation of the DEGs frequently occurred, and several methylated CpG sites of the DEGs significantly correlated with outcomes of HCC patients. The immune infiltration in the tumor microenvironment of HCC was correlated with the expression level of the DEGs. Besides, the DEGs and their co-expressive genes participated in the biological processes of extracellular matrix (ECM) organization and focal adhesion. In summary, this study indicated the dysregulation of ECM and focal adhesion might contribute to the formation of PVTT. And the above seven genes might serve as potential biomarkers of PVTT occurrence and prognosis of HCC patients.

CHPF Regulates the Aggressive Phenotypes of Hepatocellular Carcinoma Cells via the Modulation of the Decorin and TGF-β Pathways

Simple Summary

Altered extracellular chondroitin sulfate (CS) contributes to tumor progression in many cancers. CHPF is a key enzyme supporting the elongation of CS. Here we showed that CHPF was frequently downregulated in hepatocellular carcinoma (HCC) tumors compared with adjacent non-tumor tissues, and its downregulation was associated with poor overall survival. CHPF regulated aggressive phenotypes of HCC cells in vitro and in vivo, and the TGF-β pathway involved in the phenotypical changes. Mechanistically, CHPF modified CS on decorin (DCN), which could facilitate DCN accumulation surrounding HCC cells, and modulate activation of TGF-β pathway. Indeed, the expression of DCN were positively associated with CHPF levels in primary HCC tissue. The research proposed novel insights into the significance of CHPF, which modified DCN and modulated TGF-β signaling.

Abstract

Aberrant composition of glycans in the tumor microenvironment (TME) and abnormal expression of extracellular matrix proteins are hallmarks of hepatocellular carcinoma (HCC); however, the mechanisms responsible for establishing the TME remain unclear. We demonstrate that the chondroitin polymerizing factor (CHPF), an enzyme that mediates the elongation of chondroitin sulfate (CS), is a critical elicitor of the malignant characteristics of HCC as it modifies the potent tumor suppressor, decorin (DCN). CHPF expression is frequently downregulated in HCC tumors, which is associated with the poor overall survival of HCC patients. We observed that restoring CHPF expression suppressed HCC cell growth, migration, and invasion in vitro and in vivo. Mechanistic investigations revealed that TGF-β signaling is associated with CHPF-induced phenotype changes. We found that DCN, as a TGF-β regulator, is modified by CHPF, and that it affects the distribution of DCN on the surface of HCC cells. Importantly, our results confirm that CHPF and DCN expression levels are positively correlated in primary HCC tissues. Taken together, our results suggest that CHPF dysregulation contributes to the malignancy of HCC cells, and our study provides novel insights into the significance of CS, which affects DCN expression in the TME.

Effect of decorin and selected glycosylation inhibitors on the adhesion of caruncular epithelial cells of pregnant cows-part I

Adhesion process ensures the formation of the appropriate connection between mother and foetus during placentation and further placental development, which determines physiological pregnancy course. Extracellular matrix of foetal membranes are a rich source of biologically active proteins, the synthesis of which is regulated by hormones. Depending on the stage of pregnancy, the protein profile of the placenta changes, thanks to which its remodelling is possible. The aim of the study was to evaluate the effect of decorin, as well as selected glycosylation inhibitors on the adhesion of caruncular epithelial cells derived from cows during pregnancy. Placental cells were isolated from healthy, pregnant (2nd and 4th month) cows after slaughter, which allowed for the establishment of 4 primary cell cultures without visible cells of fibroblast morphology. The presence of decorin in cell monolayer and cell lysates was determined by the use of immunocytochemistry and Western blotting, respectively. The viability of cells was evaluated by MTT assay. The adhesion of cells to fibronectin was measured spectrophotometrically. Protein N-glycosylation and O-glycosylation have a modulating effect on the adhesion and viability of placental cells during early-mid pregnancy. Decorin and tunicamycin were shown to have anti-adhesive properties with respect to caruncular cells of the pregnant bovine uterus.

Decorin deficiency promotes epithelial-mesenchymal transition and colon cancer metastasis

The tumor microenvironment encompasses a complex cellular network that includes cancer-associated fibroblasts, inflammatory cells, neo-vessels, and an extracellular matrix enriched in angiogenic growth factors. Decorin is one of the main components of the tumor stroma, but it is not expressed by cancer cells. Lack of this proteoglycan correlates with down-regulation of E-cadherin and induction of β-catenin signaling. In this study, we investigated the role of a decorin-deficient tumor microenvironment in colon carcinoma progression and metastasis. We utilized an established model of colitis-associated cancer by administering Azoxymethane/Dextran sodium sulfate to adult wild-type and Dcn^-/- mice. We discovered that after 12 weeks, all the animals developed intestinal tumors independently of their genotype. However, the number of intestinal neoplasms was significantly higher in the Dcn^-/- microenvironment vis-à-vis wild-type mice. Mechanistically, we found that under unchallenged basal conditions, the intestinal epithelium of the Dcn^-/- mice showed a significant increase in the protein levels of epithelial-mesenchymal transition associated factors including Snail, Slug, Twist, and MMP2. In comparison, in the colitis-associated cancer evoked in the Dcn^-/- mice, we found that intercellular adhesion molecule 1 (ICAM-1) was also significantly increased, in parallel with epithelial-mesenchymal transition signaling pathway-related factors. Furthermore, a combined Celecoxib/decorin treatment revealed a promising therapeutic efficacy in treating human colorectal cancer cells, in decorin-deficient animals. Collectively, our results shed light on colorectal cancer progression and provide a protein-based therapy, i.e., treatment using recombinant decorin, to target the tumor microenvironment.

Decorin in the Tumor Microenvironment

The tumor microenvironment plays a determining role in cancer development through a plethora of interactions between the extracellular matrix and tumor cells. Decorin is a prototype member of the SLRP family found in a variety of tissues and is expressed in the stroma of various forms of cancer. Decorin has gained recognition for its essential roles in inflammation, fibrotic disorders, and cancer, and due to its antitumor properties, it has been proposed to act as a "guardian from the matrix." Initially identified as a natural inhibitor of transforming growth factor-β, soluble decorin is emerging as a pan-RTK inhibitor targeting a multitude of RTKs, including EGFR, Met, IGF-IR, VEGFR2, and PDGFR. Besides initiating signaling, decorin/RTK interaction can induce caveosomal internalization and receptor degradation. Decorin also triggers cell cycle arrest and apoptosis and evokes antimetastatic and antiangiogenic processes. In addition, as a novel regulatory mechanism, decorin was shown to induce conserved catabolic processes, such as endothelial cell autophagy and tumor cell mitophagy. Therefore, decorin is a promising candidate for combatting cancer, especially the cancer types heavily dependent on RTK signaling.

The Protective Role of Decorin in Hepatic Metastasis of Colorectal Carcinoma

Decorin, the prototype member of the small leucine-rich proteoglycan gene family of extracellular matrix (ECM) proteins, acts as a powerful tumor suppressor by inducing the p21^Waf1/Cip1 cyclin-dependent kinase inhibitor, as well as through its ability to directly bind and block the action of several tyrosine kinase receptors. Our previous studies suggested that the lack of decorin promotes hepatic carcinogenesis in mice. Based on this, we set out to investigate whether excess decorin may protect against the liver metastases of colon carcinoma. We also analyzed the effect of decorin in tissue microarrays of human colon carcinoma liver metastasis and examined whether the tumor cells can directly influence the decorin production of myofibroblasts. In humans, low levels of decorin in the liver facilitated the development of colon carcinoma metastases in proportion with more aggressive phenotypes, indicating a possible antitumor action of the proteoglycan. In vitro, colon carcinoma cells inhibited decorin expression in LX2 hepatic stellate cells. Moreover, liver-targeted decorin delivery in mice effectively attenuated metastasis formation of colon cancer. Overexpressed decorin reduced the activity of multiple receptor tyrosine kinases (RTKs) including the epidermal growth factor receptor (EGFR), an important player in colorectal cancer (CRC) pathogenesis. Downstream of that, we observed weakened signaling of ERK1/2, PLCγ, Akt/mTOR, STAT and c-Jun pathways, while p38 MAPK/MSK/CREB and AMPK were upregulated culminating in enhanced p53 function. In conclusion, decorin may effectively inhibit metastatic tumor formation in the liver.

Network of clinically-relevant lncRNAs-mRNAs associated with prognosis of hepatocellular carcinoma patients

Long non-coding RNAs (lncRNAs) are often aberrantly expressed in Hepatocellular Carcinoma (HCC). We hypothesize that lncRNAs modulate HCC prognoses through differential deregulation of key lncRNAs affecting important gene network in key cancer pathways associated with pertinent clinical phenotype. Here, we present a novel approach integrating lncRNA-mRNA expression profiles with clinical characteristics to identify lncRNA signatures in clinically-relevant co-expression lncRNA-mRNA networks residing in pertinent cancer pathways. Notably one network, associated with poorer prognosis, comprises five up-regulated lncRNAs significantly correlated (|Pearson Correlation Coefficient|≥ 0.9) with 91 up-regulated genes in the cell-cycle and Rho-GTPase pathways. All 5 lncRNAs and 85/91 (93.4%) of the correlated genes were significantly associated with higher tumor-grade while 3/5 lncRNAs were also associated with no tumor capsule. Interestingly, 2/5 lncRNAs that are correlated with numerous genes in this oncogenic network were experimentally shown to up-regulate genes involved in cell-cycle and transcriptional regulation. Another network comprising 4 down-regulated lncRNAs and 8 down-regulated metallothionein-family genes are significantly associated with tumor invasion. The identification of these key lncRNAs signatures that deregulate important network of genes in key cancer pathways associated with pertinent clinical phenotype may facilitate the design of novel therapeutic strategies targeting these 'master' regulators for better patient outcome.

The Roles of Glycans in Bladder Cancer

Bladder cancer is one of the most common malignant tumors of the urogenital system with high morbidity and mortality worldwide. Early diagnosis and personalized treatment are the keys to successful bladder cancer treatment. Due to high postoperative recurrence rates and poor prognosis, it is urgent to find suitable therapeutic targets and biomarkers. Glycans are one of the four biological macromolecules in the cells of an organism, along with proteins, nucleic acids, and lipids. Glycans play important roles in nascent peptide chain folding, protein processing, and translation, cell-to-cell adhesion, receptor-ligand recognition, and binding and cell signaling. Glycans are mainly divided into N-glycans, O-glycans, proteoglycans, and glycosphingolipids. The focus of this review is the discussion of glycans related to bladder cancer. Additionally, this review also addresses the clinical value of glycans in the diagnosis and treatment of bladder cancer. Abnormal glycans are likely to be potential biomarkers for bladder cancer.

Fibroblast heterogeneity and its impact on extracellular matrix and immune landscape remodeling in cancer

Tumor progression is marked by dense collagenous matrix accumulations that dynamically reorganize to accommodate a growing and invasive tumor mass. Cancer-associated fibroblasts (CAFs) play an essential role in matrix remodeling and influence other processes in the tumor microenvironment, including angiogenesis, immunosuppression, and invasion. These findings have spawned efforts to elucidate CAF functionality at the single-cell level. Here, we will discuss how those efforts have impacted our understanding of the ways in which CAFs govern matrix remodeling and the influence of matrix remodeling on the development of an immunosuppressive tumor microenvironment.

Identification of key miRNAs in the progression of hepatocellular carcinoma using an integrated bioinformatics approach

Backgroud

It has been shown that aberrant expression of microRNAs (miRNAs) and transcriptional factors (TFs) is tightly associated with the development of HCC. Therefore, in order to further understand the pathogenesis of HCC, it is necessary to systematically study the relationship between the expression of miRNAs, TF and genes. In this study, we aim to identify the potential transcriptomic markers of HCC through analyzing common microarray datasets, and further establish the differential co-expression network of miRNAs-TF-mRNA to screen for key miRNAs as candidate diagnostic markers for HCC.

Method

We first downloaded the mRNA and miRNA expression profiles of liver cancer from the GEO database. After pretreatment, we used a linear model to screen for differentially expressed genes (DEGs) and miRNAs. Further, we used weighed gene co-expression network analysis (WGCNA) to construct the differential gene co-expression network for these DEGs. Next, we identified mRNA modules significantly related to tumorigenesis in this network, and evaluated the relationship between mRNAs and TFs by TFBtools. Finally, the key miRNA was screened out in the mRNA-TF-miRNA ternary network constructed based on the target TF of differentially expressed miRNAs, and was further verified with external data set.

Results

A total of 465 DEGs and 215 differentially expressed miRNAs were identified through differential genes expression analysis, and WGCNA was used to establish a co-expression network of DEGs. One module that closely related to tumorigenesis was obtained, including 33 genes. Next, a ternary network was constructed by selecting 256 pairs of mRNA-TF pairs and 100 pairs of miRNA-TF pairs. Network mining revealed that there were significant interactions between 18 mRNAs and 25 miRNAs. Finally, we used another independent data set to verify that miRNA hsa-mir-106b and hsa-mir-195 are good classifiers of HCC and might play key roles in the progression of HCC.

Conclusion

Our data indicated that two miRNAs-hsa-mir-106b and hsa-mir-195-are identified as good classifiers of HCC.

Protective Role of Decorin in Primary Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) represents one of the most frequent type of primary liver cancers. Decorin, a small leucine-rich proteoglycan of the extracellular matrix, represents a powerful tumor cell growth and migration inhibitor by hindering receptor tyrosine kinases and inducing p21^WAF1/CIP1. In this study, first we tested decorin expression in HCCs utilizing in silico data, as well as formalin fixed paraffin embedded tissue samples of HCC in a tissue microarray (TMA). In silico data revealed that DCN/SMA mRNA ratio is decreased in HCC compared to normal tissues and follows the staging of the disease. Among TMA samples, 52% of HCCs were decorin negative, 33% exhibited low, and 15% high decorin levels corroborating in silico results. In addition, applying conditioned media of hepatoma cells inhibited decorin expression in LX2 stellate cells in vitro. These results raise the possibility that decorin acts as a tumor suppressor in liver cancer and that is why its expression decreased in HCCs. To further test the protective role of decorin, the proteoglycan was overexpressed in a mouse model of hepatocarcinogenesis evoked by thioacetamide (TA). After transfection, the excessive proteoglycan amount was mainly detected in hepatocytes around the central veins. Upon TA-induced hepatocarcinogenesis, the highest tumor count was observed in mice with no decorin production. Decorin gene delivery reduced tumor formation, in parallel with decreased pEGFR, increased pIGF1R levels, and with concomitant induction of pAkt (T308) and phopho-p53, suggesting a novel mechanism of action. Our results suggest the idea that decorin can be utilized as an anti-cancer agent.

Impact of Decorin on the Physical Function and Prognosis of Patients with Hepatocellular Carcinoma

The outcome of patients with hepatocellular carcinoma (HCC) is still poor. Decorin is a small leucine-rich proteoglycan, which exerts antiproliferative and antiangiogenic properties in vitro. We aimed to investigate the associations of decorin with physical function and prognosis in patients with HCC. We enrolled 65 patients with HCC treated with transcatheter arterial chemoembolization (median age, 75 years; female/male, 25/40). Serum decorin levels were measured using enzyme-linked immunosorbent assays; patients were classified into the High or Low decorin groups by median levels. Associations of decorin with physical function and prognosis were evaluated by multivariate correlation and Cox regression analyses, respectively. Age and skeletal muscle indices were not significantly different between the High and Low decorin groups. In the High decorin group, the 6-min walking distance was significantly longer than the Low decorin group and was significantly correlated with serum decorin levels (r = 0.2927, p = 0.0353). In multivariate analysis, the High decorin group was independently associated with overall survival (hazard ratio 2.808, 95% confidence interval 1.016–8.018, p = 0.0498). In the High decorin group, overall survival rate was significantly higher than in the Low decorin group (median 732 days vs. 463 days, p = 0.010). In conclusion, decorin may be associated with physical function and prognosis in patients with HCC.

The Tumor Microenvironment: Focus on Extracellular Matrix

The extracellular matrix (ECM) regulates the development and maintains tissue homeostasis. The ECM is composed of a complex network of molecules presenting distinct biochemical properties to regulate cell growth, survival, motility, and differentiation. Among their components, proteoglycans (PGs) are considered one of the main components of ECM. Its composition, biomechanics, and anisotropy are exquisitely tuned to reflect the physiological state of the tissue. The loss of ECM's homeostasis is seen as one of the hallmarks of cancer and, typically, defines transitional events in tumor progression and metastasis. In this chapter, we discuss the types of proteoglycans and their roles in cancer. It has been observed that the amount of some ECM components is increased, while others are decreased, depending on the type of tumor. However, both conditions corroborate with tumor progression and malignancy. Therefore, ECM components have an increasingly important role in carcinogenesis and this leads us to believe that their understanding may be a key in the discovery of new anti-tumor therapies. In this book, the main ECM components will be discussed in more detail in each chapter.

Chrysophanol exhibits inhibitory activities against colorectal cancer by targeting decorin

Colorectal cancer (CRC) is a common human malignancy that accounts for 600,000 deaths annually worldwide. Chrysophanol, a naturally occurring anthraquinone compound, exhibits anti-neoplastic effects in various cancer cells. The aim of this study was to explore the biological effects of chrysophanol on CRC cells, and determine the underlying mechanism. Chrysophanol inhibited proliferation of and promoted apoptosis in CRC cells by activating the intrinsic mitochondrial apoptotic pathway. In addition, chrysophanol also suppressed tumor growth in vivo and increased the percentage of apoptotic cells in tumor xenografts, without general toxicity. Proteomic iTRAQ analysis revealed decorin (DCN) as the major target of chrysophanol. DCN was upregulated in the tumor tissues following chrysophanol treatment, and ectopic DCN expression markedly augmented the pro-apoptotic effects of chrysophanol in CRC cells. In contrast, DCN knockdown significantly abrogated chrysophanol-induced apoptosis in CRC cells. Taken together, chrysophanol exerts anti-neoplastic effects in vitro and in vivo in CRC cells by modulating DCN, there by highlighting its therapeutic potential in CRC.

Tumor-specific inhibitory action of decorin on different hepatoma cell lines

BACKGROUND

In spite of therapeutic approaches, liver cancer is still one of the deadliest type of tumor in which tumor microenvironment may play an active role in the outcome of the disease. Decorin, a small leucine-rich proteoglycan is not only responsible for assembly and maintenance of the integrity of the extracellular matrix, but a natural inhibitor of cell surface receptors, thus it exerts antitumorigenic effects. Here we addressed the question whether this effect of decorin is independent of the tumor phenotypes including differentiation, proliferation and invasion.

METHOD

Four hepatoma cell lines HepG2, Hep3B, HuH7 and HLE, possessing different molecular backgrounds, were selected to investigate. After proliferation tests, pRTK arrays, WB analyses, and immunofluorescent examinations were performed on decorin treated and control cells for comparison.

RESULTS

Significant growth inhibitory potential of decorin on three out of four hepatoma cell lines was proven, however the mode of its action was different. Induction of p21^WAF1/CIP1, increased inactivation of c-myc and β-catenin, and decrease of EGFR, GSK3β and ERK1/2 phosphorylation levels were observed in HepG2 cells, pathways already well-described in literature. However, in the p53 deficient Hep3B and HuH7, InsR and IGF-1R were the main receptors transmitting signals. In harmony with its receptor status, Hep3B cells displayed high level of activated AKT. As the cell line is retinoblastoma mutant, ATR/Chk1/Wee1 system might hinder the cell cycle in G2/M phase via phosphorylation of CDK1. In Huh7 cells, all RTKs were inhibited by decorin followed by downregulation of AKT. Furthermore, HuH7 cell line responded with concentration-dependent ERK activation and increased phospho-c-myc level. Decorin had only a non-significant effect on the proliferation rate of HLE cell line. However, it responded with a significant decrease of pAKT, c-myc and β-catenin activity. In this special cell line, the inhibition of TGFβ may be the first step of the protective effect of decorin.

CONCLUSIONS

Based on our results decorin may be a candidate therapeutic agent in the battle against liver cancer, but several questions need to be answered. It is certain that decorin is capable to exert its suppressor effect in hepatoma cells without respect to their phenotype and molecular background.

Generation of a multi-functional, target organ-specific, anti-fibrotic molecule by molecular engineering of the extracellular matrix protein, decorin

Extracellular matrix (ECM) molecules play important roles in regulating processes such as cell proliferation, migration, differentiation and survival. Decorin is a proteoglycan that binds to ('decorates') collagen fibrils in the ECM. Decorin also interacts with many growth factors and their receptors, the most notable of these interactions being its inhibitory activity on TGF-β, the growth factor responsible for fibrosis formation. We have generated a recombinant, multi-functional, fusion-protein consisting of decorin as a therapeutic domain and a vascular homing and cell-penetrating peptide as a targeting vehicle. This recombinant decorin (CAR-DCN) accumulates at the sites of the targeted disease at higher levels and, as a result, has substantially enhanced biological activity over native decorin. CAR-DCN is an example of how molecular engineering can give a compound the ability to seek out sites of disease and enhance its therapeutic potential. CAR-DCN will hopefully be used to treat severe human diseases. LINKED ARTICLES: This article is part of a themed section on Translating the Matrix. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.1/issuetoc.

Promotion of bone cancer pain development by decorin is accompanied by modification of excitatory synaptic molecules in the spinal cord

Bone cancer pain is refractory to currently available clinical treatment owing to its complicated underlying mechanisms. Studies found that extracellular matrix molecules can participate in the regulation of chronic pain. Decorin is one of the most abundant extracellular matrix molecules, and the present study evaluated the effect of decorin on the development of bone cancer pain. We found that decorin was upregulated in the L4–L6 spinal dorsal horn of the bone cancer pain rats. Spinal microinjection of a decorin-targeting RNAi lentivirus alleviated bone cancer pain-induced mechanical allodynia and reduced the expression of pGluR1-Ser831 in the bone cancer pain rats. Meanwhile, decorin knockdown impaired the excitatory synaptogenesis in cultured neurons and prevented the clustering and insertion of pGluR1-Ser831 into postsynaptic membranes. Taken together, the results of our study suggested that decorin contributes to the development of bone cancer pain possibly by regulating the activity of excitatory synaptic molecules in the spinal cord. Our findings provide a better understanding of the function of decorin as a possible therapeutic target for alleviating bone cancer pain.

Proteoglycans Are Attractive Biomarkers and Therapeutic Targets in Hepatocellular Carcinoma

Proteoglycans, which consist of a protein core and glycosaminoglycan chains, are major components of the extracellular matrix and play physiological roles in maintaining tissue homeostasis. In the carcinogenic tissue microenvironment, proteoglycan expression changes dramatically. Altered proteoglycan expression on tumor and stromal cells affects cancer cell signaling pathways, which alters growth, migration, and angiogenesis and could facilitate tumorigenesis. This dysregulation of proteoglycans has been implicated in the pathogenesis of diseases such as hepatocellular carcinoma (HCC) and the underlying mechanism has been studied extensively. This review summarizes the current knowledge of the roles of proteoglycans in the genesis and progression of HCC. It focuses on well-investigated proteoglycans such as serglycin, syndecan-1, glypican 3, agrin, collagen XVIII/endostatin, versican, and decorin, with particular emphasis on the potential of these factors as biomarkers and therapeutic targets in HCC regarding the future perspective of precision medicine toward the "cure of HCC".

Identifying Key Genes of Liver Cancer by Networking of Multiple Data Sets

Liver cancer is one of the deadliest cancers in the world. To find effective therapies for this cancer, it is indispensable to identify key genes, which may play critical roles in the incidence of the liver cancer. To identify key genes of the liver cancer with high accuracy, we integrated multiple microarray gene expression data sets to compute common differentially expressed genes, which will result more accurate than those from individual data set. To find the main functions or pathways that these genes are involved in, some enrichment analyses were performed including functional enrichment analysis, pathway enrichment analysis, and disease association study. Based on these genes, a protein-protein interaction network was constructed and analyzed to identify key genes of the liver cancer by combining the local and global influence of nodes in the network. The identified key genes, such as TOP2A, ESR1, and KMO, have been demonstrated to be key biomarkers of the liver cancer in many publications. All the results suggest that our method can effectively identify key genes of the liver cancer. Moreover, our method can be applied to other types of data sets to select key genes of other complex diseases.

Decorin promotes proliferation and migration of ORS keratinocytes and maintains hair anagen in mice

DECORIN is a prototypical member of the small leucine-rich proteoglycan (SLRP) family that plays important roles in numerous biological processes and cellular biological pathways. We previously showed that Decorin expression was highly enhanced in mouse dorsal hair follicles (HFs) during the anagen phase and was reduced during the catagen and telogen phases, suggesting that Decorin might modulate follicular cycling and morphogenesis. In this study, to further clarify the effects of DECORIN on hair cells and the cycling transition, an in vitro overexpression strategy and Decorin-null (Dcn^-/- ) mice were used to investigate the effects of DECORIN on outer root sheath (ORS) keratinocytes. DECORIN overexpression significantly enhanced proliferation and migration in ORS keratinocytes in vitro. Moreover, DECORIN overexpression upregulated the mRNA and protein expression levels of WNT10b, β-CATENIN and LEF1. The DECORIN overexpression-induced increase in the proliferation and migration of ORS keratinocytes was partially inhibited by a Wnt/β-catenin inhibitor. Furthermore, Dcn^-/- mice had a shortened anagen phase and lower levels of β-catenin expression than were observed in wild-type mice in imaging and histological analyses. Taken together, these findings suggest that DECORIN promotes the proliferation and migration of ORS keratinocytes in vitro and maintains hair anagen in mice.

Decorin is a devouring proteoglycan: Remodeling of intracellular catabolism via autophagy and mitophagy

Autophagy, a fundamental and evolutionarily-conserved eukaryotic pathway, coordinates a complex balancing act for achieving both nutrient and energetic requirements for proper cellular function and homeostasis. We have discovered that soluble proteoglycans evoke autophagy in endothelial cells and mitophagy in breast carcinoma cells by directly interacting with receptor tyrosine kinases, including VEGF receptor 2 and Met. Under these circumstances, autophagic regulation is considered "non-canonical" and is epitomized by the bioactivity of the small leucine-rich proteoglycan, decorin. Soluble matrix-derived cues being transduced downstream of receptor engagement converge upon a newly-discovered nexus of autophagic machinery consisting of Peg3 for endothelial cell autophagy and mitostatin for tumor cell mitophagy. In this thematic mini-review, we will provide an overview of decorin-mediated autophagy and mitophagy and propose that regulating intracellular catabolism is the underlying molecular basis for the versatility of decorin as a potent oncosuppressive agent.

β-defensin 1 expression in HCV infected liver/liver cancer: an important role in protecting HCV progression and liver cancer development

β-defensin family plays a role in host defense against viral infection, however its role in HCV infection is still unknown. In this study, we demonstrated that β-defensin 1 was significantly reduced in HCV-infected liver specimens. Treatment with interferon and ribavirin upregulated β-defensin-1, but not other β-defensin tested, with the extent and duration of upregulation associated with treatment response. We investigated β-defensin family expression in liver cancer in publicly available datasets and found that among all the β-defensins tested, only β-defensin 1 was significantly downregulated, suggesting β-defensin 1 plays a crucial role in liver cancer development. Further analysis identified E-cadherin as the top positive correlated gene, while hepatocyte growth factor-regulated tyrosine kinase substrate as the top negative correlated gene. Expression of two proteoglycans were also positively correlated with that of β-defensin 1. We have also identified small molecules as potential therapeutic agents to reverse β-defensin 1-associated gene signature. Furthermore, the downregulation of β-defensin 1 and E-cadherin, and upregulation of hepatocyte growth factor-regulated tyrosine kinase substrate, were further confirmed in liver cancer and adjacent normal tissue collected from in-house Chinese liver cancer patients. Together, our results suggest β-defensin 1 plays an important role in protecting HCV progression and liver cancer development.

AP4 modulated by the PI3K/AKT pathway promotes prostate cancer proliferation and metastasis of prostate cancer via upregulating L-plastin

The transition from androgen-dependent to metastatic castration-resistant prostate cancer (PCa) is a lethal event of uncertain molecular aetiology. Our previous studies demonstrated that L-plastin is involved in PCa invasion and metastasis and is upregulated by androgen and oestrogen in the hormone-dependent PCa cell line LNCaP. We recently found that L-plastin expression is consistently activated even after androgen deprivation, suggesting that androgen-independent transcription factors may regulate its expression. Herein, we performed sequential deletion and luciferase analysis of the L-plastin promoter and found that an androgen-independent regulatory factor prominently located in the region close to the transcription initiation site (−216 to +118) may facilitate L-plastin upregulation. AP4 was then identified as the relevant transcription activator that directly binds to the L-plastin promoter, as confirmed by EMSAs, supershift assays and CHIP-qPCR experiments. Moreover, we determined that the AP4/L-plastin axis is regulated by the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, contributing to PCa metastasis and castration resistance. Furthermore, we found that AP4 promotes PCa metastasis by upregulating L-plastin expression in vitro and in vivo. We collected a total of 136 PCa tissues and corresponding adjacent normal tissues from patients who underwent prostatectomy at Sun Yat-Sen Memorial Hospital from 2005 to 2015 and measured AP4 and L-plastin protein levels by immunohistochemistry. The results showed that AP4 levels strongly correlated with those of its downstream target gene L-plastin, were significantly upregulated in PCa tissues, were positively correlated with lymph node metastasis and Gleason scores over 7, and were an independent prognostic factor for patient survival. In summary, these findings support a plausible mechanism by which the AP4/L-plastin axis is regulated by the PI3K/AKT pathway in human PCa and may represent a novel therapeutic target in PCa treatment.

Human Metaplastic Breast Carcinoma and Decorin

Metaplastic breast carcinoma (MBC) is a rare subtype of invasive breast cancer and has poor prognosis. In general, cancers are heterogeneous cellular masses comprised of different cell types and their extracellular matrix (ECM). However, little is known about the composition of the ECM and its constituents in MBC. Decorin is a ubiquitous ECM macromolecule known of its oncosuppressive activity. As such, it provides an intriguing molecule in the development of novel therapeutics for different malignancies such as MBC. In this study, decorin immunoreactivity and the effect of adenoviral decorin cDNA (Ad-DCN) transduction were examined in MBC. Multiple immunohistochemical stainings were used to characterize a massive breast tumour derived from an old woman. Furthermore, three-dimensional (3D) explant cultures derived from the tumour were transduced with Ad-DCN to study the effect of the transduction on the explants. The MBC tumour was shown to be completely negative for decorin immunoreactivity demonstrating that the malignant cells were not able to synthesize decorin. Ad-DCN transduction resulted in a markedly altered cytological phenotype of MBC explants by decreasing the amount of atypical cells and by inhibiting cell proliferation. The results of this study support approaches to develop new, decorin-based adjuvant therapies for MBC.

Decorin-inducible Peg3 Evokes Beclin 1-mediated Autophagy and Thrombospondin 1-mediated Angiostasis

We previously discovered that systemic delivery of decorin for treatment of breast carcinoma xenografts induces paternally expressed gene 3 (Peg3), an imprinted gene encoding a zinc finger transcription factor postulated to function as a tumor suppressor. Here we found that de novo expression of Peg3 increased Beclin 1 promoter activity and protein expression. This process required the full-length Peg3 as truncated mutants lacking either the N-terminal SCAN domain or the zinc fingers failed to translocate to the nucleus and promote Beclin 1 transcription. Importantly, overexpression of Peg3 in endothelial cells stimulated autophagy and concurrently inhibited endothelial cell migration and evasion from a 3D matrix. Mechanistically, we found that Peg3 induced the secretion of the powerful angiostatic glycoprotein Thrombospondin 1 independently of Beclin 1 transcriptional induction. Thus, we provide a new mechanism whereby Peg3 can simultaneously evoke autophagy in endothelial cells and attenuate angiogenesis.

A transcriptome profile in hepatocellular carcinomas based on integrated analysis of microarray studies

Background

Despite new treatment options for hepatocellular carcinomas (HCC) recently, 5-year survival remains poor, ranging from 50 to 70%, which may attribute to the lack of early diagnostic biomarkers. Thus, developing new biomarkers for early diagnosis of HCC, is extremely urgent, aiming to decrease HCC-related deaths.

Methods

In the study, we conducted a comprehensive characterization of gene expression data of HCC based on a bioinformatics method. The results were confirmed by real time polymerase chain reaction (RT-PCR) and TCGA database to prove the credibility of this integrated analysis.

Results

After integrating analysis of seven HCC gene expression datasets, 1167 differential expressed genes (DEGs) were identified. These genes mainly participated in the process of cell cycle, oocyte meiosis, and oocyte maturation mediated by progesterone. The results of experiments and TCGA database validation in 10 genes was in full accordance with findings in integrated analysis, indicating the high credibility of our integrated analysis of different gene expression datasets. ASPM, CCT3, and NEK2 was showed to be significantly associated with overall survival of HCC patients in TCGA database.

Conclusion

This method of integrated analysis may be a useful tool to minish the heterogeneity of individual microarray, hopefully outputs more accurate HCC transcriptome profiles based on large sample size, and explores some potential biomarkers and therapy targets for HCC.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-016-0596-x) contains supplementary material, which is available to authorized users.

High Energy Particle Radiation-associated Oncogenic Transformation in Normal Mice: Insight into the Connection between Activation of Oncotargets and Oncogene Addiction

Concerns on high-energy particle radiation-induced tumorigenic transformation of normal tissue in astronauts, and in cancer patients undergoing radiotherapy, emphasizes the significance of elucidating the mechanisms involved in radiogenic transformation processes. Mostly used genetically modified or tumor-prone models are less reliable in determining human health risk in space or protracted post-treatment normal tissue toxicity. Here, in wild type C57BL/6 mice, we related the deregulation of distinctive set of tissue-specific oncotargets in major organs upon ⁵⁶Fe (600 MeV/amu; 0.5 Gy/min; 0.8 Gy) particle radiation and compared the response with low LET γ-radiation (¹³⁷Cs; 0.5 Gy/min; 2 Gy). One of the novel findings is the ‘tissue-independent’ activation of TAL2 upon high-energy radiation, and thus qualifies TAL2 as a potential biomarker for particle and other qualities of radiation. Heightened expression of TAL2 gene transcript, which sustained over four weeks post-irradiation foster the concept of oncogene addiction signaling in radiogenic transformation. The positive/negative expression of other selected oncotargets that expresses tissue-dependent manner indicated their role as a secondary driving force that addresses the diversity of tissue-dependent characteristics of tumorigenesis. This study, while reporting novel findings on radiogenic transformation of normal tissue when exposed to particle radiation, it also provides a platform for further investigation into different radiation quality, LET and dose/dose rate effect in healthy organs.

Decorin interacting network: A comprehensive analysis of decorin-binding partners and their versatile functions

Decorin, a prototype small leucine-rich proteoglycan, regulates a vast array of cellular processes including collagen fibrillogenesis, wound repair, angiostasis, tumor growth, and autophagy. This functional versatility arises from a wide array of decorin/protein interactions also including interactions with its single glycosaminoglycan side chain. The decorin-binding partners encompass numerous categories ranging from extracellular matrix molecules to cell surface receptors to growth factors and enzymes. Despite the diversity of the decorin interacting network, two main roles emerge as prominent themes in decorin function: maintenance of cellular structure and outside-in signaling, culminating in anti-tumorigenic effects. Here we present contemporary knowledge regarding the decorin interacting network and discuss in detail the biological relevance of these pleiotropic interactions, some of which could be targeted by therapeutic interventions.

Extracellular matrix structure

Extracellular matrix (ECM) is a non-cellular three-dimensional macromolecular network composed of collagens, proteoglycans/glycosaminoglycans, elastin, fibronectin, laminins, and several other glycoproteins. Matrix components bind each other as well as cell adhesion receptors forming a complex network into which cells reside in all tissues and organs. Cell surface receptors transduce signals into cells from ECM, which regulate diverse cellular functions, such as survival, growth, migration, and differentiation, and are vital for maintaining normal homeostasis. ECM is a highly dynamic structural network that continuously undergoes remodeling mediated by several matrix-degrading enzymes during normal and pathological conditions. Deregulation of ECM composition and structure is associated with the development and progression of several pathologic conditions. This article emphasizes in the complex ECM structure as to provide a better understanding of its dynamic structural and functional multipotency. Where relevant, the implication of the various families of ECM macromolecules in health and disease is also presented.

Decorin as a multivalent therapeutic agent against cancer

Decorin is a prototypical small leucine-rich proteoglycan that epitomizes the multifunctional nature of this critical gene family. Soluble decorin engages multiple receptor tyrosine kinases within the target-rich environment of the tumor stroma and tumor parenchyma. Upon receptor binding, decorin initiates signaling pathways within endothelial cells downstream of VEGFR2 that ultimately culminate in a Peg3/Beclin 1/LC3-dependent autophagic program. Concomitant with autophagic induction, decorin blunts capillary morphogenesis and endothelial cell migration, thereby significantly compromising tumor angiogenesis. In parallel within the tumor proper, decorin binds multiple RTKs with high affinity, including Met, for a multitude of oncosuppressive functions including growth inhibition, tumor cell mitophagy, and angiostasis. Decorin is also pro-inflammatory by modulating macrophage function and cytokine secretion. Decorin suppresses tumorigenic growth, angiogenesis, and prevents metastatic lesions in a variety of in vitro and in vivo tumor models. Therefore, decorin would be an ideal therapeutic candidate for combating solid malignancies.

Proteoglycans in liver cancer

Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain, such as a heparan, dermatan, chondroitin, or keratan sulfate, covalently attached to the protein core. These molecules are categorized based on their structure, localization, and function, and can be found in the extracellular matrix, on the cell surface, and in the cytoplasm. Cell-surface heparan sulfate proteoglycans, such as syndecans, are the primary type present in healthy liver tissue. However, deterioration of the liver results in overproduction of other proteoglycan types. The purpose of this article is to provide a current summary of the most relevant data implicating proteoglycans in the development and progression of human and experimental liver cancer. A review of our work and other studies in the literature indicate that deterioration of liver function is accompanied by an increase in the amount of chondroitin sulfate proteoglycans. The alteration of proteoglycan composition interferes with the physiologic function of the liver on several levels. This article details and discusses the roles of syndecan-1, glypicans, agrin, perlecan, collagen XVIII/endostatin, endocan, serglycin, decorin, biglycan, asporin, fibromodulin, lumican, and versican in liver function. Specifically, glypicans, agrin, and versican play significant roles in the development of liver cancer. Conversely, the presence of decorin could potentially provide protective effects.

Decorin: A Growth Factor Antagonist for Tumor Growth Inhibition

Decorin (DCN) is the best characterized member of the extracellular small leucine-rich proteoglycan family present in connective tissues, typically in association with or “decorating” collagen fibrils. It has substantial interest to clinical medicine owing to its antifibrotic, anti-inflammatory, and anticancer effects. Studies on DCN knockout mice have established that a lack of DCN is permissive for tumor development and it is regarded as a tumor suppressor gene. A reduced expression or a total disappearance of DCN has been reported to take place in various forms of human cancers during tumor progression. Furthermore, when used as a therapeutic molecule, DCN has been shown to inhibit tumor progression and metastases in experimental cancer models. DCN affects the biology of various types of cancer by targeting a number of crucial signaling molecules involved in cell growth, survival, metastasis, and angiogenesis. The active sites for the neutralization of different growth factors all reside in different parts of the DCN molecule. An emerging concept that multiple proteases, especially those produced by inflammatory cells, are capable of cleaving DCN suggests that native DCN could be inactivated in a number of pathological inflammatory conditions. In this paper, we review the role of DCN in cancer.

Deregulation of decorin and FHL1 are associated with esophageal squamous cell carcinoma progression and poor prognosis

To investigate the expression of FHL1 and Decorin in esophageal squamous cell carcinoma (ESCC) and its clinical significance. 82 ESCC tissues were evaluated by immunohistochemistry for the expression of FHL1 and Decorin. The role of the expression of FHL1 and Decorin in ESCC were statistically analyzed. The expression level of FHL1 and Decorin were reduced in malignant tissue samples in comparison to normal matched tissue (P < 0.05). It was also proved that the positive expressions of FHL1 and Decorin were associated with ESCC histological grade, lymph node metastasis, tumor stage and clinical stage (P < 0.05). In addition, the Kaplan-Meier survival curves revealed that the positive expressions of FHL1 and Decorin were associated with favorable prognosis in ESCC patients. Multivariate analysis showed that the positive expressions of FHL1 and Decorin were independent prognostic markers of overall survival of ESCC patients, respectively. The positive expressions of FHL1 and Decorin were associated with ESCC progression and good prognosis. Our results indicate that the positive expressions of FHL1 and Decorin were independent prognostic factors for patients with esophageal cancer, which might be potential valuable biomarkers for ESCC.

Systemic Delivery of an Oncolytic Adenovirus Expressing Decorin for the Treatment of Breast Cancer Bone Metastases

The development of novel therapies for breast cancer bone metastasis is a major unmet medical need. Toward that end, we have constructed an oncolytic adenovirus, Ad.dcn, and a nonreplicating adenovirus, Ad(E1-).dcn, both containing the human decorin gene. Our in vitro studies showed that Ad.dcn produced high levels of viral replication and the decorin protein in the breast tumor cells. Ad(E1-).dcn-mediated decorin expression in MDA-MB-231 cells downregulated the expression of Met, β-catenin, and vascular endothelial growth factor A, all of which are recognized decorin targets and play pivotal roles in the progression of breast tumor growth and metastasis. Adenoviral-mediated decorin expression inhibited cell migration and induced mitochondrial autophagy in MDA-MB-231 cells. Mice bearing MDA-MB-231-luc skeletal metastases were systemically administered with the viral vectors, and skeletal tumor growth was monitored over time. The results of bioluminescence imaging and X-ray radiography indicated that Ad.dcn and Ad(E1-).dcn significantly inhibited the progression of bone metastases. At the terminal time point, histomorphometric analysis, micro-computed tomography, and bone destruction biomarkers showed that Ad.dcn and Ad(E1-).dcn reduced tumor burden and inhibited bone destruction. A nonreplicating adenovirus Ad(E1-).luc expressing the luciferase 2 gene had no significant effect on inhibiting bone metastases, and in several assays, Ad.dcn and Ad(E1-).dcn were better than Ad.luc, a replicating virus expressing the luciferase 2 gene. Our data suggest that adenoviral replication coupled with decorin expression could produce effective antitumor responses in a MDA-MB-231 bone metastasis model of breast cancer. Thus, Ad.dcn could potentially be developed as a candidate gene therapy vector for treating breast cancer bone metastases.

The small leucine-rich repeat proteoglycans in tissue repair and atherosclerosis

Proteoglycans consist of a protein core with one or more covalently attached glycosaminoglycan (GAG) side chains and have multiple roles in the initiation and progression of atherosclerosis. Here we discuss the potential and known functions of a group of small leucine-rich repeat proteoglycans (SLRPs) in atherosclerosis. We focus on five SLRPs, decorin, biglycan, lumican, fibromodulin and PRELP, because these have been detected in atherosclerotic plaques or demonstrated to have a role in animal models of atherosclerosis. Decorin and biglycan are modified post-translationally by substitution with chondroitin/dermatan sulphate GAGs, whereas lumican, fibromodulin and PRELP have keratan sulphate side chains, and the core proteins have leucine-rich repeat (LRR) motifs that are characteristic of the LRR superfamily. The chondroitin/dermatan sulphate GAG side chains have been implicated in lipid retention in atherosclerosis. The core proteins are discussed here in the context of (i) interactions with collagens and their implications in tissue integrity, fibrosis and wound repair and (ii) interactions with growth factors, cytokines, pathogen-associated molecular patterns and cell surface receptors that impact normal physiology and disease processes such as inflammation, innate immune responses and wound healing (i.e. processes that are all important in plaque development and progression). Thus, studies of these SLRPs in the context of wound healing are providing clues about their functions in early stages of atherosclerosis to plaque vulnerability and cardiovascular disease at later stages. Understanding of signal transduction pathways regulated by the core protein interactions is leading to novel roles and therapeutic potential for these proteins in wound repair and atherosclerosis.