Fibulin-3 suppresses Wnt/β-catenin signaling and lung cancer invasion

Wnt/β-catenin signaling in the development and therapeutic resistance of non-small cell lung cancer

Wnt/β-catenin signaling is a critical pathway that influences development and therapeutic response of non-small cell lung cancer (NSCLC). In recent years, many Wnt regulators, including proteins, miRNAs, lncRNAs, and circRNAs, have been found to promote or inhibit signaling by acting on Wnt proteins, receptors, signal transducers and transcriptional effectors. The identification of these regulators and their underlying molecular mechanisms provides important implications for how to target this pathway therapeutically. In this review, we summarize recent studies of Wnt regulators in the development and therapeutic response of NSCLC.

Small extracellular vesicles: Multi-functional aspects in non-small cell lung carcinoma

Extracellular vesicles (EVs) impact normal and pathological cellular signaling through bidirectional trafficking. Exosomes, a subset of EVs possess biomolecules including proteins, lipids, DNA fragments and various RNA species reflecting a speculum of their parent cells. The involvement of exosomes in bidirectional communication and their biological constituents substantiate its role in regulating both physiology and pathology, including multiple cancers. Non-small cell lung cancer (NSCLC) is the most common lung cancers (85%) with high incidence, mortality and reduced overall survival. Lack of efficient early diagnostic and therapeutic tools hurdles the management of NSCLC. Interestingly, the exosomes from body fluids similarity with parent cells or tissue offers a potential future multicomponent tool for the early diagnosis of NSCLC. The structural twinning of exosomes with a cell/tissue and the competitive tumor derived exosomes in tumor microenvironment (TME) promotes the unpinning horizons of exosomes as a drug delivery, vaccine, and therapeutic agent. Exosomes in clinical point of view assist to trace: acquired resistance caused by various therapeutic agents, early diagnosis, progression, and surveillance. In an integrated approach, EV biomarkers offer potential cutting-edge techniques for the detection and diagnosis of cancer, though the purification, characterization, and biomarker identification processes for the translational research regarding EVs need further optimization.

The multifaceted roles of matrix metalloproteinases in lung cancer

Background

Though the matrix metalloproteinases (MMPs) are widely investigated in lung cancer (LC), however, almost no review systematically clarify their multi-faced roles in LC.

Methods

We investigated the expression of MMPs and their effects on survival of patients with LC, the resistance mechanisms of MMPs in anti-tumor therapy, the regulatory networks of MMPs involved, the function of MMPs inducing CSCLs, MMPs-related tumor immunity, and effects of MMP polymorphisms on risk of LC.

Results

High expression of MMPs was mainly related to poor survival, high clinical stages and cancer metastasis. Role of MMPs in LC are multi-faced. MMPs are involved in drug resistance, induced CSCLs, participated in tumor immunity. Besides, MMPs polymorphisms may increase risk of LC.

Conclusions

MMPs might be promising targets to restore the anti-tumor immune response and enhance the killing function of nature immune cells in LC.

The Diagnostic and Prognostic Significance of EFEMP1 in Breast Cancer: An Immunohistochemistry Study

EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1) has been associated to a variety of malignancies. Because EFEMP1 can act as both a tumor suppressor and an oncogene, this study aimed to evaluate the expression of EFEMP1 at mRNA and protein in breast cancer and to ascertain the diagnostic and prognostic value of EFEMP1 in relation to clinical features of breast cancer. Several bioinformatics websites such as GEPIA and Oncomine databases were used to analyze the mRNA level of EFEMP1. Immunohistochemistry assay was used to detect EFEMP1 immunoexpression using tissue microarray (TMA) and clinical breast cancer samples. EFEMP1 was shown to be overexpressed in breast cancer in some study cohorts while being low expressed in others. In TMA, 86 patients (39.1%) with a high H-score and 134 patients (60.9%) with a low H-score had EFEMP1 positive for breast cancer. While HER2 breast cancer and normal breast tissues had the lowest expression of EFEMP1, it was shown to be highly expressed in Luminal B, A, and TNBC. EFEMP1 H-score is associated with tumor stage and indicates poor overall survival in breast cancer. EFEMP1 H-score was high in the clinical tumor tissues compared with adjacent normal tissue (n = 20), therefore, it would to be a sensitive biomarker for breast cancer. EFEMP1 is a key indicator for assessing the clinical prognosis and diagnosis of patients with breast cancer, as evidenced by the higher expression of EFEMP1 in tumor tissue compared to normal tissue and its association with poor overall survival.

Function and prognostic value of basement membrane -related genes in lung adenocarcinoma

Background: Lung adenocarcinoma (LUAD) has become a common cause of cancer-related death. Many studies have shown that the basement membrane (BM) is associated with the development of cancer. However, BM-related gene expression and its relationship to LUAD prognosis remains unclear. Methods: BM-related genes from previous studies were used. Clinical and mRNA expression information were obtained from TCGA database. Cox, minimum absolute contraction, and selection operator regression were applied to analyze the selected genes affecting LUAD prognosis. A prognostic-risk model was then established. Furthermore, this study applied Kaplan-Meier analysis to assess the outcomes of high- and low-risk groups, then explored their differences in drug sensitivity. The DSigDB database was used to screen for therapeutic small-molecule drugs. Results: Fourteen prognostic models based on BM-related genes were successfully constructed and validated in patients with LUAD. We also found that independence was a prognostic factor in all 14 BM-based models. Functional analysis showed that the enrichment of BM-related genes mainly originated from signaling pathways related to cancer. The BM-based model also suggested that immune cell infiltration is associated with checkpoints. The low-risk patients may benefit from cyclopamine and docetaxel treatments. Conclusion: This study identified a reliable biomarker to predict survival in patients with LUAD and offered new insights into the function of BM-related genes in LUAD.

Fibulin-3 sponges Tiam1 to manipulate MMP-7 activity through β-catenin signaling in oral squamous cell carcinoma

Oral squamous cell carcinoma (named OSCC) is considered the most frequent malignancy in oral cavity, which has become a rapid increasing problem for the global public health with unclear molecular mechanism. Previously, Tiam1 (T-lymphoma invasion and metastasis inducing factor 1) has been reported as a potential oncogene for OSCC. Here, we in-depth explored its signaling mechanism for the disorder. The mRNA and protein expression levels of primary differentially expressed genes (Tiam1, Fibulin-3, and MMP-7) were measured in different TNM stages of OSCC patients using RT-PCR and ELISA methods. Based on the analysis of human OSCC cell line CAL27, the relationships between these factors have been further investigated and the interactions were also examined. The luciferase reporter assay was established for the promoter region of MMP-7. Both the epithelial (E-cadherin) and mesenchymal protein markers (Vimentin and Snail) expressions were examined using western blotting. The mRNA and protein activities of Fibulin-3 declined as the increase of TNM stage. Inversely, the mRNA and protein levels of Tiam1 and MMP-7 elevated significantly as OSCC progressed. Tiam1 transfection in CAL27 cells stimulated the expression of MMP-7 by accelerating the nuclear translocation of β-catenin, which was opposite to the functions of Fibulin-3. Moreover, Tiam1 interacted directly with Fibulin-3. The Tiam1 induced OSCC epithelial-mesenchymal transition (EMT) via MMP-7 activation, which was dependent on the direct binding of β-catenin at the promoter region. Collectively, these results indicated that Tiam1 competed with Fibulin-3 for nuclear β-catenin translocation, which subsequently stimulated MMP-7 expression by TCF-4 domain interaction following EMT initiation in OSCC development. Our systematical work hypothesized an innovative signaling cassette for OSCC progression, which provided beneficial references for future clinical study.

Fibulin-3 Deficiency Protects Against Myocardial Injury Following Ischaemia/ Reperfusion in in vitro Cardiac Spheroids

Myocardial infarction (MI, or heart attack) is a leading cause of death worldwide. Myocardial ischaemia reperfusion (I/R) injury typical of MI events is also associated with the development of cardiac fibrosis and heart failure in patients. Fibulin-3 is an extracellular matrix component that plays a role in regulating MI response in the heart. In this study, we generated and compared in vitro cardiac spheroids (CSs) from wild type (WT) and fibulin-3 knockout (Fib-3 KO) mice. These were then exposed to pathophysiological changes in oxygen (O₂) concentrations to mimic an MI event. We finally measured changes in contractile function, cell death, and mRNA expression levels of cardiovascular disease genes between WT and Fib-3 KO CSs. Our results demonstrated that there are significant differences in growth kinetics and endothelial network formation between WT and Fib-3 KO CSs, however, they respond similarly to changes in O₂ concentrations. Fib-3 deficiency resulted in an increase in viability of cells and improvement in contraction frequency and fractional shortening compared to WT I/R CSs. Gene expression analyses demonstrated that Fib-3 deficiency inhibits I/R injury and cardiac fibrosis and promotes angiogenesis in CSs. Altogether, our findings suggest that Fib-3 deficiency makes CSs resistant to I/R injury and associated cardiac fibrosis and helps to improve the vascular network in CSs.

EGFR-Dependent Extracellular Matrix Protein Interactions Might Light a Candle in Cell Behavior of Non-Small Cell Lung Cancer

Lung cancer remains the leading cause of cancer-related death and is associated with a poor prognosis. Lung cancer is divided into 2 main types: the major in incidence is non-small cell lung cancer (NSCLC) and the minor is small cell lung cancer (SCLC). Although NSCLC progression depends on driver mutations, it is also affected by the extracellular matrix (ECM) interactions that activate their corresponding signaling molecules in concert with integrins and matrix metalloproteinases (MMPs). These signaling molecules include cytoplasmic kinases, small GTPases, adapter proteins, and receptor tyrosine kinases (RTKs), particularly the epidermal growth factor receptor (EGFR). In NSCLC, the interplay between ECM and EGFR regulates ECM stiffness, angiogenesis, survival, adhesion, migration, and metastasis. Furthermore, some tumor-promoting ECM components (e.g., glycoproteins and proteoglycans) enhance activation of EGFR and loss of PTEN. On the other hand, other tumor-suppressing glycoproteins and -proteoglycans can inhibit EGFR activation, suppressing cell invasion and migration. Therefore, deciphering the molecular mechanisms underlying EGFR and ECM interactions might provide a better understanding of disease pathobiology and aid in developing therapeutic strategies. This review critically discusses the crosstalk between EGFR and ECM affecting cell behavior of NSCLC, as well as the involvement of ECM components in developing resistance to EGFR inhibition.

Extracellular Vesicles in Lung Cancer Metastasis and Their Clinical Applications

Extracellular vesicles (EVs) are heterogenous membrane-encapsulated vesicles secreted by every cell into the extracellular environment. EVs carry bioactive molecules, including proteins, lipids, DNA, and different RNA forms, which can be internalized by recipient cells, thus altering their biological characteristics. Given that EVs are commonly found in most body fluids, they have been widely described as mediators of communication in several physiological and pathological processes, including cancer. Moreover, their easy detection in biofluids makes them potentially useful candidates as tumor biomarkers. In this manuscript, we review the current knowledge regarding EVs and non-coding RNAs and their role as drivers of the metastatic process in lung cancer. Furthermore, we present the most recent applications for EVs and non-coding RNAs as cancer therapeutics and their relevance as clinical biomarkers.

Effects of the decrease of β-catenin expression on human vaginal fibroblasts of women with pelvic organ prolapse

BACKGROUND

Pelvic organ prolapse (POP) lowers the quality of life in elderly women, and there have been no studies on its role in the pathogenesis of POP. The purpose of this study is to investigate the effect of β-catenin on proliferation and collagen anabolism in human vaginal fibroblasts (HVFs).

MATERIALS AND METHODS

The adherence and differential adherence methods were used to culture and purify HVFs. RNA interference was applied to knockdown β-catenin and lithium chloride was used to activate Wnt/β-catenin signaling pathway. β-catenin nuclear translocation was tested by immunofluorescence, and HVF proliferation was detected by performing MTT assays.

RESULTS

The expression of β-catenin, phosphorylated-β-catenin, phosphorylated-glycogen synthase kinase 3β (p-GSK3β), collagen I, matrix metalloproteinase 2 (MMP2), and tissue-derived inhibitors of metalloproteinases 2 (TIMP2) was assessed by western blot analysis. The expression of β-catenin and collagen I was lower in HVFs of POP group than that of control group. The proliferation rate of HVFs in POP group was lower than that in control group. Knockdown of β-catenin decreased the cell proliferation rate and the expression of collagen I. Lithium chloride can activate the Wnt/β-catenin signaling pathway.

CONCLUSION

β-catenin participates in the proliferation and collagen I synthesis of HVFs. The decrease of β-catenin expression may be closely related to the occurrence, and development of POP. LiCl can activate the Wnt/β-catenin signaling pathway in HVFs and thus increase HVFs proliferation and collagen synthesis.

Circulating and local nuclear expression of survivin and fibulin-3 genes in discriminating benign from malignant respiratory diseases: correlation analysis

Survivin is an inhibitor of apoptosis as well as a promoter of cell proliferation. Fibulin-3 is a matrix glycoprotein that displays potential for tumor suppression or propagation. The present study aimed to validate the expression levels of survivin and fibulin-3 in benign and malignant respiratory diseases. This case-control study included 219 patients categorized into five groups. Group A included 63 patients with lung cancer, group B included 63 patients with various benign lung diseases, group D included 45 patients with malignant pleural mesothelioma (MPM), and group E included 48 patients with various benign pleural diseases. Group C included 60 healthy individuals (control group). Serum survivin and fibulin-3 levels were measured by ELISA, whereas their nuclear expressions in the lung and pleura were assessed via Western blot analysis. The results showed significantly higher survivin serum levels and significantly lower fibulin-3 levels in group A compared with in group B and controls (P<0.001). There were significantly higher serum levels of survivin and fibulin-3 in group D compared with in group E and controls (P<0.001), consistent with observed nuclear survivin and fibulin-3 expression levels. Fibulin-3 was determined to have higher value than survivin in discriminating lung cancer from MPM (P<0.05). Survivin and fibulin-3 could be useful diagnostic markers for lung and pleural cancers, and fibulin-3 expression was particularly useful in differentiating lung cancer from MPM.

Regulation of cellular senescence by extracellular matrix during chronic fibrotic diseases

The extracellular matrix (ECM) is a complex network of macromolecules surrounding cells providing structural support and stability to tissues. The understanding of the ECM and the diverse roles it plays in development, homoeostasis and injury have greatly advanced in the last three decades. The ECM is crucial for maintaining tissue homoeostasis but also many pathological conditions arise from aberrant matrix remodelling during ageing. Ageing is characterised as functional decline of tissue over time ultimately leading to tissue dysfunction, and is a risk factor in many diseases including cardiovascular disease, diabetes, cancer, dementia, glaucoma, chronic obstructive pulmonary disease (COPD) and fibrosis. ECM changes are recognised as a major driver of aberrant cell responses. Mesenchymal cells in aged tissue show signs of growth arrest and resistance to apoptosis, which are indicative of cellular senescence. It was recently postulated that cellular senescence contributes to the pathogenesis of chronic fibrotic diseases in the heart, kidney, liver and lung. Senescent cells negatively impact tissue regeneration while creating a pro-inflammatory environment as part of the senescence-associated secretory phenotype (SASP) favouring disease progression. In this review, we explore and summarise the current knowledge around how aberrant ECM potentially influences the senescent phenotype in chronic fibrotic diseases. Lastly, we will explore the possibility for interventions in the ECM-senescence regulatory pathways for therapeutic potential in chronic fibrotic diseases.

The Pathophysiological Significance of Fibulin-3

Fibulin-3 (also known as EGF-containing fibulin extracellular matrix protein 1 (EFEMP1)) is a secreted extracellular matrix glycoprotein, encoded by the EFEMP1 gene that belongs to the eight-membered fibulin protein family. It has emerged as a functionally unique member of this family, with a diverse array of pathophysiological associations predominantly centered on its role as a modulator of extracellular matrix (ECM) biology. Fibulin-3 is widely expressed in the human body, especially in elastic-fibre-rich tissues and ocular structures, and interacts with enzymatic ECM regulators, including tissue inhibitor of metalloproteinase-3 (TIMP-3). A point mutation in EFEMP1 causes an inherited early-onset form of macular degeneration called Malattia Leventinese/Doyne honeycomb retinal dystrophy (ML/DHRD). EFEMP1 genetic variants have also been associated in genome-wide association studies with numerous complex inherited phenotypes, both physiological (namely, developmental anthropometric traits) and pathological (many of which involve abnormalities of connective tissue function). Furthermore, EFEMP1 expression changes are implicated in the progression of numerous types of cancer, an area in which fibulin-3 has putative significance as a therapeutic target. Here we discuss the potential mechanistic roles of fibulin-3 in these pathologies and highlight how it may contribute to the development, structural integrity, and emergent functionality of the ECM and connective tissues across a range of anatomical locations. Its myriad of aetiological roles positions fibulin-3 as a molecule of interest across numerous research fields and may inform our future understanding and therapeutic approach to many human diseases in clinical settings.

Cancer associated fibroblast mediated chemoresistance: A paradigm shift in understanding the mechanism of tumor progression

One of the undeniable issues with cancer eradication is the evolution of chemoresistance in due course of treatment, and the mechanisms of chemoresistance have been the subject of extensive research for several years. The efficacy of chemotherapy is hindered by cancer epithelium, mostly in a cell-autonomous mechanism. However, recently the valid experimental evidence showed that the surrounding tumor microenvironment (TME) is equivalently responsible for the induction of chemoresistance. Of the verities of cells in the tumor microenvironment, cancer-associated fibroblasts (CAFs) are the major cellular component of TME and act as a key regulator in the acquisition of cancer chemoresistance by providing a protective niche to the cancer cells against the anti-cancer drugs. Moreover, the symbiotic relationship between the tumor and CAFs to obtain key resources such as growth factors and nutrients for optimal tumor growth and proliferation favors the chemoresistance phenotype. Here, in this review, we provide an up-to-date overview of our knowledge of the role of the CAFs in inducing chemoresistance and tumor progression. We also further delineated the emerging events leading to the CAF origins and activation of normal fibroblasts to CAFs. Along with this, we also discuss the novel area of research confined to the CAF targeted therapies of cancer. The identification of CAF-specific markers may allow unveiling new targets and avenues for blunting or reverting the detrimental pro-tumorigenic potential of CAFs in the foreseeable future.

WDR74 induces nuclear β-catenin accumulation and activates Wnt-responsive genes to promote lung cancer growth and metastasis

Lung cancer has been notorious for its lack of advance in clinical therapy, urging for effective therapeutic targets. WD repeat-containing protein 74 (WDR74) has previously been implicated in tumorigenesis, but its mechanistic functions remain not well understood. Herein, WDR74 expression was observed to be increased upon lung cancer progression from healthy normal tissues to the primary cancer and further to the metastatic cancer. Through gain- and loss-of-function approaches, we found that WDR74 regulated lung cancer cell proliferation, cell cycle progression, chemoresistance and cell aggressiveness in vitro. Moreover, a xenograft mouse model disclosed that WDR74 knockout inhibited lung cancer growth and metastasis, whereas WDR74 overexpression reciprocally enhanced these characteristics. Mechanistically, WDR74 promoted nuclear β-catenin accumulation and drove downstream Wnt-responsive genes, thus revealing that WDR74 activated the Wnt/β-catenin signaling pathway. Collectively, WDR74 inducing nuclear β-catenin accumulation and driving the downstream Wnt-responsive genes expression facilitates lung cancer growth and metastasis. WDR74 can serve as a candidate target for the prevention and treatment of lung cancer in clinic.

EFEMP2 Suppresses the Invasion of Lung Cancer Cells by Inhibiting Epithelial-Mesenchymal Transition (EMT) and Down-Regulating MMPs

Background

Epidermal growth factor-containing fibulin-like extracellular matrix protein 2 (EFEMP2), also known as fibulin-4, MBP1 and UPH1, is an extracellular matrix protein associated with a variety of tumors. The purpose of this study was to investigate the prognostic value and the function of EFEMP2 in lung cancer.

Methods

The mRNA and protein expression of EFEMP2 in lung normal and cancer tissues, lung cancer cell lines (A549, H460, H1299 and H1650) and normal epithelial cell line BEAS-2B were evaluated by immunohistochemistry, RT-qPCR and Western blotting. The Public databases (Oncomine and Kaplan-Meier plotter) were used to investigate the prognostic value of EFEMP2 in lung cancer. RNA interference (RNAi) and overexpression transfection were performed to detect the effects of EFEMP2 up- or down-regulation on lung normal and cancer cell proliferation, invasion and metastasis in vitro and in vivo.

Results

EFEMP2 was lowly expressed in lung cancer tissues and cells, and its low expression was associated with malignant phenotype and poor prognosis of lung cancer. The same conclusion had been drawn from the Public databases. EFEMP2 overexpression significantly inhibited the invasion of lung cancer cells, hampered the process of EMT, and decreased the expression and activity of MMP2 and MMP9, while EFEMP2 knockdown remarkably enhanced the invasion of lung cancer cells, promoted EMT, and increased the expression and activity of MMP2 and MMP9.

Conclusion

The low expression of EFEMP2 was detected in lung cancer and was positively correlated with the poor prognosis of patients. EFEMP2 was a tumor suppressor gene that inhibited the progress of lung cancer, which suggested a new research objective for the future studies.

Exosome-mediated transfer of miR-1260b promotes cell invasion through Wnt/β-catenin signaling pathway in lung adenocarcinoma

Increasing evidence confirms that exosome-mediated transfer of microRNAs can influence cancer progression including tumor cell invasion, cell proliferation, and drug resistance via cell-cell communication. However, the potential role of exosomal-miR-1260b in lung adenocarcinoma (LAC) remains poorly understood. Thus, this study focused on investigating the function of exosomal-miR-1260b on cell invasion. Exosomal-miR-1260b was found to be higher in plasma of patients with LAC than that of healthy persons via quantitative real-time polymerase chain reaction assay. The sensitivity and specificity of exosomal-miR-1260b (cutoff point: 2.027) were 72% and 86%, and area under the curve of 0.845 (95% CI = 0.772-0.922). Elevated expression of miR-1260b in LAC tissues was positively correlated with exosomal-miR-1260b in plasma (r = .642, p < .05). Furthermore, ceramide biosynthesis regulated exosomal-miR-1260b secretion. Exosome-mediated transfer of miR-1260b promoted A549 cell invasion and was still functional inside A549 cells. Moreover, exosomal-miR-1260b regulated Wnt/β-catenin signaling pathway by inhibiting sFRP1 and Smad4. This study identified a new regulation mechanism involving in cell invasion by exosome-mediated tumor-cell-to-tumor-cell communication. Targeting exosome-microRNAs may provide new insights into the diagnosis and treatment of LAC.

EFEMP2 Inhibits Breast Cancer Invasion And Metastasis In Vitro And In Vivo

Background

EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2) is an extracellular matrix (ECM) glycoprotein, which is regarded as potential prognostic biomarkers in some carcinoma. Little is known about the association of EFEMP2 and breast cancer.

Methods

EFEMP2 expressions in normal breast tissue, benign fibroadenoma, breast cancer, the normal mammary epithelial cell line, and 4 different invasive breast cancer cell lines were evaluated by immunohistochemistry (IHC) or immunocytochemistry (ICC) and real time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). Expression and prognostic value of EFEMP2 in breast cancer were verified by the Public databases (Oncomine and Kaplan-Meier plotter database). Lentiviral vector with EFEMP2 cDNA was constructed and used to infect breast cancer cell lines to investigate the effects of EFEMP2 on the biological behavior of breast cancer cells by functional in vitro and in vivo assays.

Results

Down-regulated EFEMP2 expression was found in breast cancer tissues and cells, and low expression of EFEMP2 was associated with poor prognosis in patients with breast cancer. Analysis by the Public database leaded to the same conclusion. Up-regulated EFEMP2 expression significantly hampered the invasion and metastasis abilities of breast cancer cells and the process of epithelial interstitial transformation (EMT) via the Wnt/β-catenin pathway.

Conclusion

EFEMP2 expression was lower in breast cancer and closely related to the prognosis of patients, its anti-oncogenic roles indicated the underlying therapeutic target for the future treatment of breast cancer.

Novel Associations Within the Tumor Microenvironment: Fibulins Meet ADAMTSs

The maintenance of tissue homeostasis in any organism is a very complex and delicate process in which numerous factors intervene. Cellular homeostasis not only depends on intrinsic factors but also relies on external factors that compose the microenvironment or cellular niche. Thus, extracellular matrix (ECM) components play a very important role in maintaining cell survival and behavior, and alterations in the ECM composition can lead to different pathologies. Fibulins and ADAMTS metalloproteases play crucial roles in the upkeep and function of the ECM in different tissues. In fact, members of both of these families of secreted multidomain proteins can interact with numerous other ECM components and thus shape or regulate the molecular environment. Individual members of both families have been implicated in tumor-related processes by exhibiting either pro- or antitumor properties. Recent studies have shown both an important relation among members of both families and their participation in several pathologies, including cardiogenesis or cancer. In this review, we summarize the associations among fibulins and ADAMTSs and the effects elicited by those interactions on cellular behavior.

Negative regulators of Wnt signaling in non-small cell lung cancer: Theoretical basis and therapeutic potency

Significant advances in the treatment of non-small cell lung cancer (NSCLC) have been made over the past decade, and they predominantly involve molecular targets such as epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements. However, despite the initial good response, drug resistance eventually develops. The Wnt signaling pathway has recently been considered important in embryonic development and tumorigenesis in many cancers, particularly NSCLC. Moreover, the aberrant Wnt pathway plays a significant role in NSCLC and is associated with cancer cell proliferation, metastasis, invasion and drug resistance, and the suppression of canonical or noncanonical Wnt signaling through various biological or pharmacological negative regulators has been proven to produce specific anticancer effects. Thus, blocking the Wnt pathway via its negative regulators may overcome the resistance of current treatment methods and lead to new treatment strategies for NSCLC. Therefore, in this review, we summarize recent studies on the role of negative regulators in Wnt signaling in NSCLC and the therapeutic potency of these molecules as agents and targets for NSCLC treatments.

Bioinformatics analysis of microarray data to identify the candidate biomarkers of lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is the major subtype of lung cancer and the most lethal malignant disease worldwide. However, the molecular mechanisms underlying LUAD are not fully understood.

Methods

Four datasets (GSE118370, GSE85841, GSE43458 and GSE32863) were obtained from the gene expression omnibus (GEO). Identification of differentially expressed genes (DEGs) and functional enrichment analysis were performed using the limma and clusterProfiler packages, respectively. A protein–protein interaction (PPI) network was constructed via Search Tool for the Retrieval of Interacting Genes (STRING) database, and the module analysis was performed by Cytoscape. Then, overall survival analysis was performed using the Kaplan–Meier curve, and prognostic candidate biomarkers were further analyzed using the Oncomine database.

Results

Totally, 349 DEGs were identified, including 275 downregulated and 74 upregulated genes which were significantly enriched in the biological process of extracellular structure organization, leukocyte migration and response to peptide. The mainly enriched pathways were complement and coagulation cascades, malaria and prion diseases. By extracting key modules from the PPI network, 11 hub genes were screened out. Survival analysis showed that except VSIG4, other hub genes may be involved in the development of LUAD, in which MYH10, METTL7A, FCER1G and TMOD1 have not been reported previously to correlated with LUAD. Briefly, novel hub genes identified in this study will help to deepen our understanding of the molecular mechanisms of LUAD carcinogenesis and progression, and to discover candidate targets for early detection and treatment of LUAD.

Inhibitory effects of miR‑26b‑5p on thyroid cancer

In order to examine the inhibitory effects of microRNA (miR)‑26b‑5p on thyroid cancer (TC), the clinicopathological features and pathological tissues of 67 patients were collected. The expression levels of miR‑26b‑5p were detected in TC and paracarcinoma tissues by quantitative polymerase chain reaction, and the association between miR‑26b‑5p expression and the clinicopathological features of the patients was analyzed using t‑test or one‑way analysis of variance. In addition, B‑CPAP TC cells were infected with a lentivirus to induce miR‑26b‑5p overexpression and proliferation was detected by Cell Counting kit‑8. Subsequently, migration and invasion were detected by Transwell and Matrigel assays, respectively, and the molecular mechanism of action was investigated by western blotting. The results demonstrated that the expression levels of miR‑26b‑5p were significantly lower in TC tissues compared with paracarcinoma tissues (P<0.01), and miR‑26b‑5p was associated with lymph node metastasis (P<0.05). In addition, overexpression of miR‑26b‑5p inhibited the proliferation, invasion and migration of B‑CPAP cells. Western blot analysis demonstrated that the protein expression levels of phosphorylated glycogen synthase kinase‑3β (pGsk‑3β) were decreased, and the expression of β‑catenin was decreased in B‑CPAP cells overexpressing miR‑26b‑5p. These results demonstrated that miR‑26b‑5p may exert antitumor activity. In addition, at the molecular level, these effects may be associated with the Gsk‑3β/β‑catenin pathway.

IDH1 mutation promotes lung cancer cell proliferation through methylation of Fibulin-5

Mutation in isocitrate dehydrogenase (IDH) leads to an aberrant function of the enzyme, leading to the production of hydroxyglutarate, as well as changes in cellular metabolism, DNA methylation and histone modification. Previous studies uncovered mutations in IDH1 in several malignancies, with the most frequent mutation being IDH1 R132H. It has been demonstrated that IDH1 expression is induced in non-small-cell lung cancer (NSCLC). However, the contribution of IDH1 mutation in the malignant transformation and development of NSCLC is unclear. In our study, we show that IDH1 R132H enhanced the migration and proliferation of NSCLC cells. Moreover, IDH1 R132H was a crucial modulator of 2-hydroxyglutarate, whose production from cells with IDH1 mutation promoted the binding of DNA-methyltransferase 1 (DNMT1) to the Fibulin-5 promoter, leading to its methylation. As a result, Fibulin-5 silencing in cells with IDH1 mutation enhanced the migration and proliferation of NSCLC cells. We show that the IDH1 mutation was present in tissues sampled from patients with NSCLC, which was reversely linked to Fibulin-5 expression. In this study, we suggest an innovative model for IDH1 R132H/Fibulin-5 pathway, which could throw light upon the activity of IDH1 R132H in NSCLC.

Fibulin-3 knockdown inhibits cervical cancer cell growth and metastasis in vitro and in vivo

To explore the function of fibulin-3 in cervical carcinoma malignant cell growth and metastasis, fibulin-3 expression in normal cervical tissue, cervical intraepithelial neoplasia (CIN), and cervical carcinoma were evaluated by immunohistochemistry. Quantitative real-time-polymerase chain reaction, western blotting, and immunocytochemistry were performed to assess the expression of fibulin-3 at mRNA and protein levels in different invasive clone sublines. Fibulin-3 shRNA and fibulin-3 cDNA were used to transfect the strongly and weakly invasive clone sublines. Using in vitro and in vivo functional assays, we investigated the effects of down-regulating and up-regulating fibulin-3 expression on the proliferation and invasion of different clone sublines. Epithelial mesenchymal transition (EMT) and its signaling pathways PI3K/AKT and ERK were studied carefully in lentiviral transfection systems. Fibulin-3 was upregulated in cervical carcinoma, and its overexpression was significantly related with malignant phenotype and poor prognosis of cervical carcinoma. Fibulin-3 promoted cervical cancer cell invasive capabilities by eliciting EMT and activating the PI3K-Akt-mTOR signal transduction pathway. Fibulin-3 could facilitate the process of cervical cancer development. The results presented here will help develop novel prognostic factors and possible therapeutic options for patients with cervical cancer.

XAV939 inhibits the proliferation and migration of lung adenocarcinoma A549 cells through the WNT pathway

The present study assessed the effects of the tankyrase (TNKS) small molecule inhibitor XAV939 on the proliferation and migration of lung adenocarcinoma A549 cells and the possible underlying mechanism. To do this, the association between TNKS and the WNT/β-catenin signaling pathway in lung acinar adenocarcinoma was investigated. Immunohistochemistry was performed, which demonstrated that TNKS, β-catenin and Myc proto-oncogene protein (c-Myc) proteins are positively expressed in lung adenocarcinoma tissue; this expression was significantly higher than that in normal adjacent non-carcinoma tissues. A549 cell proliferation was inhibited in all XAV939-intervention groups examined. In the wound-healing assay, cells treated with different concentrations of XAV939 exhibited a significantly increased scratch width compared with the control group. Reverse transcription-semi-quantitative polymerase chain reaction analysis revealed that β-catenin mRNA expression was significantly decreased in A549 cells in response to different XAV939 concentrations compared with the control group. Immunofluorescence revealed that β-catenin protein, initially localized in the nucleus/cytoplasm, gradually translocated to the cytoplasm/membrane, an effect that was associated with increased drug concentration. TNKS, β-catenin and c-Myc protein expression in A549 cells treated with XAV939 was reduced compared with that in untreated cells. Therefore, abnormally high TNKS expression may promote the occurrence of lung cancer. The TNKS inhibitor XAV939 inhibited lung adenocarcinoma A549 cell proliferation and migration in vitro. The underlying mechanism by which XAV939 exerted its inhibitory effects may be associated with attenuation of the WNT signaling pathway.

EFEMP1 promotes ovarian cancer cell growth, invasion and metastasis via activated the AKT pathway

EFEMP1, a kind of extracellular matrix (ECM) protein, has been suggested to correlate with the development of different types of carcinoma. However, its functions in ovarian cancer remain unclear. In our study, we performed cDNA microarray analysis and identified EFEMP1 dramatically elevated in the highly invasive subclone, compared with the low invasive subclone. Lentivirus transfection experiments were constructed afterwards. The results demonstrated that knockdown of EFEMP1 significantly inhibited ovarian cancer cell proliferation and induced cell cycle arrest at the G1/G0 phase. We also found that decreased the activity of phospho-AKT could suppress cell invasion and metastasis. Meanwhile, the increased phospho-AKT activity induced by the overexpression of EFEMP1 had significantly enhanced the abilities of ovarian cancer cells to invade and migrate. In addition, the vivo nude mice model confirmed that EFEMP1 was tightly correlated with the development of tumor. The results of RT² Profiler EMT PCR array further indicated that decreased EFEMP1 suppressed epithelial-to-mesenchymal transition (EMT). Collectively, by activating AKT signaling pathway, EFEMP1 contributed to ovarian cancer invasion and metastasis as a positive regulator. Overall, EFEMP1 had showed the potential use in the development of new therapeutic strategies for ovarian cancer.

Esculetin Attenuates the Growth of Lung Cancer by Downregulating Wnt Targeted Genes and Suppressing NF-κB

INTRODUCTION

Esculetin was identified to inhibit cell proliferation and induce apoptosis or cell cycle arrest in several cancer cell lines. However, the effect of esculetin on lung cancer remains elusive.

METHODS

The anti-proliferative role of esculetin in murine Lewis lung carcinoma (LLC) cells was evaluated by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and colony formation assays. BALB/c mice were subcutaneously injected with LLC cells to investigate the inhibitory effect of esculetin on the growth of lung cancer xenograft. Invasive ability was detected in esculetin treated and untreated LLC cells by transwell assay. The association between esculetin and Wnt/β-catenin signaling, as well as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), was confirmed by testing the expression of c-myc, Cyclin D1 and NF-κB using Western blot.

RESULTS

Esculetin treatment in LLC cells led to significant decrease of cell proliferation in a time- and dose-dependent manner. After injection of LLC cells into mice, reduced size and weight of tumors were observed in esculetin treated mice compared to untreated mice. However, no difference in cell invasion was observed between the treated and untreated LLC cells. Notably decreased expression of c-myc, Cyclin D1 and NF-κB were observed in LLC cells with esculetin treatment compared to untreated cells.

CONCLUSION

Esculetin plays an inhibitory role in the growth of lung cancer by down-regulating c-myc, Cyclin D1 and NF-κB.

Plasma Fibulin-3 as a Potential Biomarker for Patients with Asbestos-Related Diseases in the Han Population

Fibulin-3 has been reported as a potential biomarker for mesothelioma. However, little is known about the diagnostic efficacies of fibulin-3 for asbestos-related diseases (ARDs) in China. This study was to investigate the utility of fibulin-3 for asbestos exposure and ARDs. A total of 430 subjects were recruited from Southeast China, including healthy individuals, asbestos-exposed (AE) individuals, and patients with pleural plaques (PP), asbestosis, and malignant pleural mesothelioma (MPM). Plasma fibulin-3 was measured using the enzyme-linked immunosorbent assay. Linear regression analyses were applied to explore the influencing factors of fibulin-3. Receiver operating characteristic curves were used to determine the cutoff values. The median fibulin-3 level of subjects in the mesothelioma group was higher than that in other groups. Subjects in the asbestosis group had higher median fibulin-3 level than those in the control group. A higher fibulin-3 level was found in the group with ≥10 years of asbestos exposure as compared with control groups. The AUCs of fibulin-3 for distinguishing MPM subjects from control, AE, PP, and asbestosis subjects were 0.92, 0.88, 0.90, and 0.81, respectively. Our study provided evidence that fibulin-3 could be a potential biomarker for the early screening of MPM, but not of other nonmalignant ARDs in Chinese populations.

Fibulin-4 is associated with prognosis of endometrial cancer patients and inhibits cancer cell invasion and metastasis via Wnt/β-catenin signaling pathway

Fibulin-4, an extracellular glycoprotein, which plays significant roles in elastic fiber assembly, is correlated to the progression of some cancers. However, the role of fibulin-4 in endometrial cancer cell invasion and metastasis remains unexplored. In our study, fibulin-4 expression was assessed by immunohistochemistry (IHC) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in normal endometrial tissues and endometrial carcinoma tissues. Using single cell cloning, strongly, and weakly, invasive subclones were derived from KLE and Ishikawa endometrial carcinoma cell lines. RT-qPCR, western blotting, and immunocytochemistry (ICC) were used to assess mRNA and protein expressions of fibulin-4 in primary cultured endometrial cells, 4 types of endometrial cancer cell lines, and the different invasive subclones. Using lentivirus transfection, fibulin-4 shRNA and pLVX-fibulin-4 were constructed and used to infect the strongly and weakly invasive subclones. The effects of fibulin-4 on the biological characteristics of endometrial carcinoma cells were detected by cell functional assays in vitro and in vivo. Using Wnt signaling pathway inhibitor XAV-939 and activator LiCl, we detected the role of fibulin-4 in the Wnt/β-catenin pathway and the relationship with epithelial to mesenchymal transition (EMT). Fibulin-4 was decreased in endometrial carcinoma tissues, and loss of fibulin-4 expression was significantly related with poor differentiation, lymph node metastasis, and poor prognosis of endometrial carcinoma. Fibulin-4 significantly inhibited endometrial carcinoma cell proliferation, invasion, metastasis, and EMT through the Wnt/β-catenin pathway. Fibulin-4 has the ability to suppress endometrial cancer progression. These results can contribute to the development of a new potential therapeutic target for patients with endometrial carcinoma.

WNT signaling - lung cancer is no exception

Since the initial discovery of the oncogenic activity of WNT ligands our understanding of the complex roles for WNT signaling pathways in lung cancers has increased substantially. In the current review, the various effects of activation and inhibition of the WNT signaling pathways are summarized in the context of lung carcinogenesis. Recent evidence regarding WNT ligand transport mechanisms, the role of WNT signaling in lung cancer angiogenesis and drug transporter regulation and the importance of microRNA and posttranscriptional regulation of WNT signaling are also reviewed.

LHX6, An Independent Prognostic Factor, Inhibits Lung Adenocarcinoma Progression through Transcriptional Silencing of β-catenin

Introduction: Our previous study identified LIM homeobox domain 6 (LHX6) as a frequently epigenetically silenced tumor-suppressor gene in lung cancer. However, its clinical value has never been evaluated, and the in-depth anti-tumor mechanism remains unclear.

Methods: Public database was used for lung cancer, lung adenocarcinoma and lung squamous carcinoma patients and tissue microarray data was used for lung adenocarcinoma patients to study prognostic outcome of LHX6 expression by Kaplan-Meier and Cox-regression analysis. In vitro proliferation, metastasis and in vivo nude mice model were used to evaluate the anti-tumor effect of LHX6 on lung adenocarcinoma cell lines. The mechanisms were explored using western blot, TOP/FOP flash assays and luciferase reporter assays. LHX6 expression and clinical stages data were collected from The Cancer Genome Atlas database (TCGA).

Results: Expression of LHX6 was found to be a favorable independent prognostic factor for overall survival (OS) of total lung adenocarcinoma patients (P=0.014) and patients with negative lymph nodes status (P=0.014) but not related the prognostic outcome of lung squamous cell carcinoma patients. The expression status of LHX6 significantly correlated to histological grade (P<0.01), tumor size (P=0.026), lymph node status (P=0.039) and clinical stages (P<0.01) of lung adenocarcinoma patients. Functionally, LHX6 inhibited the proliferation and metastasis of lung adenocarcinoma cells in vitro and in vivo. Furthermore, LHX6 suppressed the Wnt/β-catenin pathway through transcriptionally silencing the expression of β-catenin, and the promoter region (-1161 bp to +27 bp) was crucial for its inhibitory activity.

Conclusions: Our data indicate that the expression of LHX6 may serve as a favorable prognostic biomarker for lung adenocarcinoma patients and provide a novel mechanism of LHX6 involving in the tumorigenesis of lung adenocarcinoma.

Fibulin-3 promotes osteosarcoma invasion and metastasis by inducing epithelial to mesenchymal transition and activating the Wnt/β-catenin signaling pathway

This study explored the role of fibulin-3 in osteosarcoma progression and the possible signaling pathway involved. Fibulin-3 mRNA and protein expression in normal tissue, benign fibrous dysplasia, osteosarcoma, osteosarcoma cell lines (HOS and U-2OS), the normal osteoblastic cell line hFOB, and different invasive subclones was evaluated by immunohistochemistry (IHC) or immunocytochemistry (ICC) and real time reverse transcriptase-polymerase chain reaction (real time qRT-PCR). To assess the role of fibulin-3 in the invasion and metastasis of osteosarcoma cells, lentiviral vectors with fibulin-3 small hairpin RNA (shRNA) and pLVX-fibulin-3 were constructed and used to infect the highly invasive and low invasive subclones. The effects of fibulin-3 knockdown and upregulation on the biological behavior of osteosarcoma cells were investigated by functional in vitro and in vivo assays. The results revealed that fibulin-3 expression was upregulated in osteosarcoma, and was positively correlated with low differentiation, lymph node metastasis, and poor prognosis. Fibulin-3 could promote osteosarcoma cell invasion and metastasis by inducing EMT and activating the Wnt/β-catenin signaling pathway. Collectively, our findings demonstrate that fibulin-3 is a promoter of osteosarcoma development and progression, and suggest a novel therapeutic target for future studies.

Analysis of fibulin-3 after exposure to asbestos-like fibers

A significantly increased incidence of malignant mesothelioma in Biancavilla (Sicily, Italy) has been ascribed to exposure to fluoro-edenite, a fibrous amphibole extracted from a local stone quarry. Fibulin-3 is a highly conserved glycoprotein proposed as a biomarker for malignant mesothelioma that belongs to the family of extracellular matrix proteins. Previous studies demonstrated high Fibulin-3 plasma levels in workers with pleural plaques exposed to fluoro-edenite. Therefore, in order to gain insight into the biomolecular mechanisms of fluoro-edenite toxicity, we performed the analysis of Fibulin-3 expression by immunohistochemistry in the lung samples derived from sheep belonging to the area of Biancavilla. Furthermore, an in vitro model of exposed fluoro-edenite fibroblasts was used to perform functional experiments to better understand the modulation of Fibulin-3 expression. The percentage of immunostained area by Fibulin-3 was very much higher in exposed lungs compared with non-exposed ones. The Fibulin-3 protein level was significantly expressed in primary human lung fibroblasts exposed to 50 and 100µg/ml of fluoro-edenite fibers for 72h, compared to the unexposed controls. The results from the present study further demonstrate the implication of Fibulin-3 during fluoro-edenite exposure. This would endorse our previous results regarding the use of Fibulin-3 as a possible screening biomarker for fluoro-edenite exposed individuals, thereby contributing to the monitoring of the population at risk. The present study also suggested that the Fibulin-3 overexpression may reflect a defensive response of the tissues after exogenous stimuli and may be implicated in cancer development, especially in the context of fluoro-edenite contamination. However, further studies are necessary in order to make Fibulin-3 a customized screening tool.

Fibulin-6 regulates pro-fibrotic TGF-β responses in neonatal mouse ventricular cardiac fibroblasts

Fibulin-6, an essential component of extracellular matrix determines the architecture of cellular junctions in tissues undergoing strain. Increased expression and deposition of fibulin-6 facilitates fibroblast migration in response to TGF-β, following myocardial infarction in mouse heart. The underlying mechanism still remains elusive. In conjunction with our previous study, we have now demonstrated that in fibulin-6 knockdown (KD) fibroblasts, not only TGF-β dependent migration, but also stress fiber formation, cellular networking and subsequently fibroblast wound contraction is almost abrogated. SMAD dependent TGF-β pathway shows ~75% decreased translocation of R-SMAD and co-SMAD into the nucleus upon fibulin-6 KD. Consequently, SMAD dependent pro-fibrotic gene expression is considerably down regulated to basal levels both in mRNA and protein. Also, investigating the non-SMAD pathways we observed a constitutive increase in pERK-levels in fibulin-6 KD fibroblast compared to control, but no change was seen in pAKT. Immunoprecipitation studies revealed 60% reduced interaction of TGF-β receptor II and I (TGFRII and I) accompanied by diminished phosphorylation of TGFRI at serin165 in fibulin-6 KD cells. In conclusion, fibulin-6 plays an important role in regulating TGF-β mediated responses, by modulating TGF-β receptor dimerization and activation to further trigger downstream pathways.

WIF-1 gene inhibition and Wnt signal transduction pathway activation in NSCLC tumorigenesis

The aim of the present study is to explore the differential expression of key molecules associated with Wnt signaling in both clinical non-small cell lung cancer (NSCLC) tissue and adjacent normal lung tissue, and to discuss the tumorigenic role of the activation of Wnt signaling pathways in NSCLC. A total of 52 NSCLC patients were employed in the present study. Lung cancer tissue samples and paracarcinoma tissue samples were obtained from these patients, who had undergone surgical resection of their primary cancer. The cases were diagnosed by hematoxylin and eosin staining. Using reverse transcription-quantitative polymerase chain reaction and immunohistochemical straining, the messenger RNA (mRNA) and protein expression levels of Wnt inhibitory factor-1 (WIF-1) and important molecules associated with Wnt signaling pathways were detected. Compared with normal tissues, a marked decreased in the mRNA and protein expression levels of WIF-1, and an increase in β-catenin and cyclin D1 expression, were observed in tumor tissues. This suggests that the activation of the Wnt/β-catenin signaling pathway may be closely associated with lymph nodal metastasis and lower pathological classification. However, no obvious difference could be observed in adenomatous polyposis coli (APC) expression levels between lung cancer tissues and adjacent tissues to the carcinoma. The activation of the Wnt/β-catenin signaling pathway in NSCLC could be initiated by WIF-1 gene inhibition without APC expression changes, and this may be different to the mechanism in other tumors.

Transducin (β)-like 1 X-linked receptor 1 promotes gastric cancer progression via the ERK1/2 pathway

Gastric cancer (GC) is one of the most common types of cancer worldwide, and it involves extensive local tumour invasion, metastasis and poor prognosis. Understanding the mechanisms regulating the progression of GC is necessary for the development of effective therapeutic strategies. Transducin (β)-like 1 X-linked receptor 1 (TBL1XR1) is an important regulator controlling gene activation and repression, which has been thought to be involved in tumorigenesis. However, the role of TBL1XR1 in human GC remains largely unknown. Here, we find that TBL1XR1 is aberrantly expressed in human GC tissues, and TBL1XR1 levels are highly correlated with local tumour invasion, late tumor, lymph node, metastasis (TNM) stage and poor prognosis. Knockdown of TBL1XR1 by shRNA inhibits GC cell proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) in vitro, as well as tumorigenesis and peritoneal metastasis in vivo, whereas overexpression of TBL1XR1 produces the opposite effects. These effects are mediated by activation of the ERK1/2 signalling pathway, and inhibition of this pathway with a specific ERK1/2 inhibitor (U0126) significantly impairs the tumour-promoting effects induced by TBL1XR1. Moreover, TBL1XR1 mediated ERK1/2 activation is dependent on the β-catenin/MMP7/EGFR signalling pathway. In conclusion, TBL1XR1 contributes to GC tumorigenesis and progression through the activation of the β-catenin/MMP7/EGFR/ERK signalling pathway and may act as a new therapeutic target for GC.

Tumor microenvironment-mediated chemoresistance in breast cancer

Therapy resistance or tumor relapse in cancer is common. Tumors develop resistance to chemotherapeutic through a variety of mechanisms, with tumor microenvironment (TM) serving pivotal roles. Using breast cancer as a paradigm, we propose that responses of cancer cells to drugs are not exclusively determined by their intrinsic characteristics but are also controlled by deriving signals from TM. Affected microenvironment by chemotherapy is an avenue to promote phenotype which tends to resist on to be ruined. Therefore, exclusively targeting cancer cells does not demolish tumor recurrence after chemotherapy. Regardless of tumor-microenvironment pathways and their profound influence on the responsiveness of treatment, diversity of molecular properties of breast cancer also behave differently in terms of response to chemotherapy. And also it is assumed that there is cross-talk between phenotypic diversity and TM. Collectively, raising complex signal from TM in chemotherapy condition often encourages cancer cells are not killed but strengthen. Here, we summarized how TM modifies responses to chemotherapy in breast cancer. We also discussed successful treatment strategies have been considered TM in breast cancer treatment.

Fibulin-5 inhibits Wnt/β-catenin signaling in lung cancer

Metastatic lung cancer is incurable and a leading cause of cancer death in the United States. However, the molecular mechanism by which lung cancer cells invade other tissues has remained unclear. We previously identified fibulin-5, an extracellular matrix protein, as a frequently silenced gene in lung cancer and a suppressor of cell invasion. In this study, we found fibulin-5 functions by inhibiting the Wnt/β-catenin pathway. The Cancer Genome Atlas (TCGA) datasets show a strong association between loss of fibulin-5 expression and poor outcomes of lung cancer patients, and also activation of the Wnt target genes MMP-7 and c-Myc. Fibulin-5 impedes Wnt/β-catenin signaling by inhibiting extracellular signal-regulated kinase (ERK) to activate glycogen synthase kinase-3 β (GSK3β), which downregulates β-catenin and prevents its nuclear accumulation, leading to suppression of MMP-7 and c-Myc expression. These effects of fibulin-5 are mediated by its amino-terminal integrin-binding RGD motif. Fibulin-5 also blocks Wnt/β-catenin signaling in vivo in H460 metastasis and H1299 tumor models. Furthermore, knockdown of β-catenin suppresses metastasis of H460 tumors, while knockdown of GSK3β promotes metastasis of fibulin-5-expressing H1752 tumors. Together, our results suggest that fibulin-5 functions as a metastasis suppressor in lung cancer by modulating tumor microenvironment to suppress Wnt/β-catenin signaling.

Expansion of epigenetic alterations in EFEMP1 promoter predicts malignant formation in pancreatobiliary intraductal papillary mucinous neoplasms

Purpose

Although limited understanding exists for the presence of specific genetic mutations and aberrantly methylated genes in pancreatobiliary intraductal papillary mucinous neoplasms (IPMNs), the fundamental understanding of the dynamics of methylation expansion across CpG dinucleotides in specific gene promoters during carcinogenesis remains unexplored. Expansion of DNA methylation in some gene promoter regions, such as EFEMP1, one of the fibulin family, with tumor progression has been reported in several malignancies. We hypothesized that DNA hypermethylation in EFEMP1 promoter would expand with the tumor grade of IPMN.

Methods

A sample of 65 IPMNs and 30 normal pancreatic tissues was analyzed. IPMNs were divided into the following three subsets according to pathological findings: 31 with low-grade dysplasia (low grade), 11 with high-grade dysplasia (high grade), and 23 with associated invasive carcinoma (invasive Ca). Mutations in the KRAS or GNAS genes were analyzed by Sanger sequencing, and methylation status of two discrete regions within the EFEMP1 promoter, namely region 1 and region 2, was analyzed by bisulfite sequencing and fluorescent high-sensitive assay for bisulfite DNA (Hi-SA). Expression status of EFEMP1 was investigated by immunohistochemistry (IHC).

Results

KRAS mutations were detected in 39, 55, and 70 % of low-grade, high-grade, and invasive Ca, respectively. GNAS mutations were observed in 32, 55, and 22 % of low-grade, high-grade, and invasive Ca, respectively. The methylation of individual regions (region 1 or 2) in the EFEMP1 promoter was observed in 84, 91, and 87 % of low-grade, high-grade, and invasive Ca, respectively. However, simultaneous methylation of both regions (extensive methylation) was exclusively detected in 35 % of invasive Ca (p = 0.001) and five of eight IPMNs (63 %) with extensive methylation, whereas 20 of 57 (35.1 %) tumors of unmethylation or partial methylation of the EFEMP1 promoter region showed weak staining EFEMP1 in extracellular matrix (p = 0.422). In addition, extensive EFEMP1 methylation was particularly present in malignant tumors without GNAS mutations and associated with disease-free survival of patients with IPMNs (p < 0.0001).

Conclusions

Extensive methylation of the EFEMP1 gene promoter can discriminate invasive from benign IPMNs with superior accuracy owing to their stepwise accumulation of tumor progression.

Electronic supplementary material

The online version of this article (doi:10.1007/s00432-016-2164-x) contains supplementary material, which is available to authorized users.

Wnt signaling as potential therapeutic target in lung cancer

INTRODUCTION

Wingless-type (Wnt) signaling is tightly regulated at multiple cellular levels and is dysregulated in lung cancer. Therefore, it offers therapeutic targets for developing novel agents for lung cancer treatment.

AREAS COVERED

In this article, we discuss the role of the Wnt signaling pathway in lung cancer, highlighting the aberrant activation of Wnt in lung cancer stem cells and its implication in resistance to radiotherapy, chemotherapy and targeted therapy. We also expound the regulatory roles of microRNAs in Wnt signaling, as well as the potential of the Wnt pathway to provide biomarkers and therapeutic targets in lung cancer. The potential use of small molecule and biological inhibitors targeting the Wnt pathway for lung cancer therapy and prevention is also discussed.

EXPERT OPINION

Wnt signaling plays an important role in the development and metastasis of lung cancer; the pathway provides targets to develop agents towards for cancer prevention and therapy. A number of clinical trials have shown the effectiveness of Wnt pathway inhibitors in epithelial tumors. However, the side effects should be considered. Nevertheless, the results from clinical studies suggest that inhibitors targeting the Wnt signaling show promise against lung cancer.

Oncogenomic portals for the visualization and analysis of genome-wide cancer data

Somatically acquired genomic alterations that drive oncogenic cellular processes are of great scientific and clinical interest. Since the initiation of large-scale cancer genomic projects (e.g., the Cancer Genome Project, The Cancer Genome Atlas, and the International Cancer Genome Consortium cancer genome projects), a number of web-based portals have been created to facilitate access to multidimensional oncogenomic data and assist with the interpretation of the data. The portals provide the visualization of small-size mutations, copy number variations, methylation, and gene/protein expression data that can be correlated with the available clinical, epidemiological, and molecular features. Additionally, the portals enable to analyze the gathered data with the use of various user-friendly statistical tools. Herein, we present a highly illustrated review of seven portals, i.e., Tumorscape, UCSC Cancer Genomics Browser, ICGC Data Portal, COSMIC, cBioPortal, IntOGen, and BioProfiling.de. All of the selected portals are user-friendly and can be exploited by scientists from different cancer-associated fields, including those without bioinformatics background. It is expected that the use of the portals will contribute to a better understanding of cancer molecular etiology and will ultimately accelerate the translation of genomic knowledge into clinical practice.

Epidermal growth factor-containing fibulin-like extracellular matrix protein 1 expression and regulation in uterine leiomyoma

OBJECTIVE

To determine the presence, differential expression, and regulation of epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) in uterine leiomyomas.

DESIGN

Laboratory in vivo and in vitro study with the use of human leiomyoma and myometrial tissue and primary cells.

SETTING

Academic medical center.

SAMPLE(S)

Leiomyoma and myometrial tissue samples and cultured cells.

INTERVENTION(S)

5-Aza-2'-deoxycytidine (5-aza-dC) treatment.

MAIN OUTCOME MEASURE(S)

Fold-change difference between EFEMP1 and fibulin-3 expression in leiomyoma tissue and cells compared with matched myometrial samples, and fold-change difference in EFEMP1 expression with 5-Aza-dC treatment.

RESULT(S)

In vivo, EFEMP1 expression was 3.19-fold higher in myometrial tissue than in leiomyoma tissue. EFEMP1 expression in vitro was 5.03-fold higher in myometrial cells than in leiomyoma cells. Western blot and immunohistochemistry staining of tissue and cells confirmed similar findings in protein expression. Treatment of leiomyoma cells with 5-Aza-dC resulted in increased expression of EFEMP1 in vitro.

CONCLUSION(S)

The EFEMP1 gene and its protein product, fibulin-3, are both significantly down-regulated in leiomyoma compared with myometrium when studied both in vivo and in vitro. The increase in EFEMP1 expression in leiomyoma cells with 5-Aza-dC treatment suggest that differential methylation is responsible, in part, for the differences seen in gene expression.

Role of the LKB1/AMPK pathway in tumor invasion and metastasis of cancer cells (Review)

Liver kinase B1 (LKB1), also known as serine/threo-nine kinase 11 (STK11), is a tumor suppressor that is inactivated in Peutz-Jeghers familial cancer syndrome. LKB1 phosphorylates and activates AMP-activated protein kinase (AMPK), which negatively regulates cancer cell proliferation and metabolism. However, recent evidence demonstrates that the LKB1/AMPK pathway is involved in the process of tumor invasion and migration, which is an important hallmark of carcinoma progression to higher pathological grades of malignancy. This review focuses on the function of the LKB1/AMPK pathway in the invasion and migration of cancer cells and provides an overview of therapeutic strategies aimed at this pathway in malignant tumors.

Fibulin-3 levels in malignant pleural mesothelioma are associated with prognosis but not diagnosis

Background:

Fibulin-3 (FBLN3) was recently presented as a promising novel biomarker for malignant pleural mesothelioma (MPM), warranting independent validation studies.

Methods:

ELISA was used to measure cellular and secreted FBLN3 in cell lines, in plasma of xenograft tumour-bearing mice, in plasma from two independent series of MPM and non-MPM patients and in pleural fluid from a third series. Diagnostic and prognostic potential of FBLN3 was assessed by receiver operating characteristics curve analysis and Kaplan–Meier method, respectively.

Results:

FBLN3 was expressed in all MPM and benign mesothelial cell lines tested, and a correlation was observed between cellular protein expression and secreted levels. Human FBLN3 was detectable in plasma of tumour-bearing mice, suggesting that MPM cells contribute to levels of circulating FBLN3. Plasma FBLN3 was significantly elevated in MPM patients from the Sydney cohort, but not the Vienna cohort, but the diagnostic accuracy was low (63%, (95% CI: 50.1–76.4) and 56% (95% CI: 41.5–71.0), respectively). Although FBLN3 levels in pleural effusions were not significantly different between cases and controls, FBLN3 levels in pleural effusion fluid were found to be independently associated with prognosis (hazard ratio of 9.92 (95% CI: 2.14–45.93)).

Conclusions:

These data confirm the potential prognostic value of pleural effusion FBLN3, but question the diagnostic value of this protein in MPM patients.

TGIF1 promoted the growth and migration of cancer cells in nonsmall cell lung cancer

Transforming growth factor beta-inducing factor 1 (TGIF1) was reported to be dysregulated in several types of cancer. However, its expression pattern and functions in nonsmall cell lung cancer (NSCLC) remained unknown. In the present study, the expression of TGIF1 was found to be elevated in the clinical NSCLC tissues. TGIF1 promoted the growth and migration of NSCLC cells, while knocking down the expression of TGIF1 inhibited the growth and migration of NSCLC cells. Moreover, downregulation of TGIF1 impaired the metastasis of NSCLC cells. In the study for the molecular mechanisms, it was found that TGIF1 positively regulated beta-catenin/TCF signaling. In summary, our study demonstrated the oncogenic role of TGIF1 in NSCLC, and TGIF1 might be a therapeutic target for NSCLC.

Fibulin-3 is a novel TGF-β pathway inhibitor in the breast cancer microenvironment

TGF-β is an important regulator of breast cancer progression. However, how the breast cancer microenvironment regulates TGF-β signaling during breast cancer progression remains largely unknown. Here, we identified fibulin-3 as a secreted protein in the breast cancer microenvironment, which efficiently inhibits TGF-β signaling in both breast cancer cells and endothelial cells. Mechanistically, fibulin-3 interacts with the type I TGF-β receptor (TβRI) to block TGF-β induced complex formation of TβRI with the type II TGF-β receptor (TβRII) and subsequent downstream TGF-β signaling. Fibulin-3 expression decreases during breast cancer progression, with low fibulin-3 levels correlating with a poorer prognosis. Functionally, high fibulin-3 levels inhibited TGF-β-induced EMT, migration, invasion and endothelial permeability, while loss of fibulin-3 expression/function promoted these TGF-β-mediated effects. Further, restoring fibulin-3 expression in breast cancer cells inhibited TGF-β signaling, breast cancer cell EMT, invasion and metastasis in vivo. These studies provide a novel mechanism for how TGF-β signaling is regulated by the tumor microenvironment, and provide insight into targeting the TGF-β signaling pathway in human breast cancer patients.