Cyclooxygenase-2 is involved in the up-regulation of matrix metalloproteinase-9 in cholangiocarcinoma induced by tumor necrosis factor-alpha

13‑cis‑retinoic acid inhibits the self‑renewal, migration, invasion and adhesion of cholangiocarcinoma cells

13‑cis‑retinoic acid (13CRA), a Food and Drug Administration‑approved drug for severe acne, is currently being investigated for its potential use in skin cancer prevention. 13CRA has been reported to exhibit antitumor effects against various types of cancer cells, both in vitro and in vivo. However, to the best of our knowledge, no information is yet available regarding the effects of 13CRA on cholangiocarcinoma (CCA), a malignancy of the bile duct epithelia. Currently, there are no reliably effective therapeutic options for metastatic CCA. The present study thus aimed to evaluate the effects of 13CRA on the self‑renewal, migration, invasion and adhesion of CCA cells, and also investigated the underlying mechanisms. The results revealed that 13CRA suppressed cell proliferation via the inhibition of the self‑renewal ability of CCA cells. 13CRA induced cell cycle arrest at the G2/M phase in KKU‑100 and KKU‑213B CCA cells through the regulation of cell cycle‑regulatory genes and proteins. 13CRA reduced the cell migratory ability of both cell lines via the modulation of the genes and proteins associated with epithelial‑mesenchymal transition. 13CRA also inhibited the invasive and adhesive abilities of CCA cells via the suppression of genes and proteins associated with the invasion and adhesion of CCA cells. On the whole, these results suggested that 13CRA exerts suppressive effects on CCA cell proliferation, migration, adhesion and invasion.

Glucose and MMP-9 dual-responsive hydrogel with temperature sensitive self-adaptive shape and controlled drug release accelerates diabetic wound healing

Chronic diabetic wounds are an important healthcare challenge. High concentration glucose, high level of matrix metalloproteinase-9 (MMP-9), and long-term inflammation constitute the special wound environment of diabetic wounds. Tissue necrosis aggravates the formation of irregular wounds. All the above factors hinder the healing of chronic diabetic wounds. To solve these issues, a glucose and MMP-9 dual-response temperature-sensitive shape self-adaptive hydrogel (CBP/GMs@Cel&INS) was designed and constructed with polyvinyl alcohol (PVA) and chitosan grafted with phenylboric acid (CS-BA) by encapsulating insulin (INS) and gelatin microspheres containing celecoxib (GMs@Cel). Temperature-sensitive self-adaptive CBP/GMs@Cel&INS provides a new way to balance the fluid-like mobility (self-adapt to deep wounds quickly, approximately 37 °C) and solid-like elasticity (protect wounds against external forces, approximately 25 °C) of self-adaptive hydrogels, while simultaneously releasing insulin and celecoxib on-demand in the environment of high-level glucose and MMP-9. Moreover, CBP/GMs@Cel&INS exhibits remodeling and self-healing properties, enhanced adhesion strength (39.65 ± 6.58 kPa), down-regulates MMP-9, and promotes cell proliferation, migration, and glucose consumption. In diabetic full-thickness skin defect models, CBP/GMs@Cel&INS significantly alleviates inflammation and regulates the local high-level glucose and MMP-9 in the wounds, and promotes wound healing effectively through the synergistic effect of temperature-sensitive shape-adaptive character and the dual-responsive system.

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The hydrogel with temperature-sensitive adaptive shape can fill irregular wounds.

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The hydrogel on-demand releases drugs responding to diabetic wound environment.

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The hydrogel significantly accelerated diabetic wound healing.

The RNA m6A writer WTAP in diseases: structure, roles, and mechanisms

N6-methyladenosine (m⁶A) is a widely investigated RNA modification in studies on the "epigenetic regulation" of mRNAs that is ubiquitously present in eukaryotes. Abnormal changes in m⁶A levels are closely related to the regulation of RNA metabolism, heat shock stress, tumor occurrence, and development. m⁶A modifications are catalyzed by the m⁶A writer complex, which contains RNA methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms tumor 1-associated protein (WTAP), and other proteins with methyltransferase (MTase) capability, such as RNA-binding motif protein 15 (RBM15), KIAA1429 and zinc finger CCCH-type containing 13 (ZC3H13). Although METTL3 is the main catalytic subunit, WTAP is a regulatory subunit whose function is to recruit the m⁶A methyltransferase complex to the target mRNA. Specifically, WTAP is required for the accumulation of METTL3 and METTL14 in nuclear speckles. In this paper, we briefly introduce the molecular mechanism of m⁶A modification. Then, we focus on WTAP, a component of the m⁶A methyltransferase complex, and introduce its structure, localization, and physiological functions. Finally, we describe its roles and mechanisms in cancer.

Inflammatory Mediators in Atherosclerotic Vascular Remodeling

Atherosclerotic vascular disease remains the most common cause of ischemia, myocardial infarction, and stroke. Vascular function is determined by structural and functional properties of the arterial vessel wall, which consists of three layers, namely the adventitia, media, and intima. Key cells in shaping the vascular wall architecture and warranting proper vessel function are vascular smooth muscle cells in the arterial media and endothelial cells lining the intima. Pathological alterations of this vessel wall architecture called vascular remodeling can lead to insufficient vascular function and subsequent ischemia and organ damage. One major pathomechanism driving this detrimental vascular remodeling is atherosclerosis, which is initiated by endothelial dysfunction allowing the accumulation of intimal lipids and leukocytes. Inflammatory mediators such as cytokines, chemokines, and modified lipids further drive vascular remodeling ultimately leading to thrombus formation and/or vessel occlusion which can cause major cardiovascular events. Although it is clear that vascular wall remodeling is an elementary mechanism of atherosclerotic vascular disease, the diverse underlying pathomechanisms and its consequences are still insufficiently understood.

Promoter hypermethylation of early B cell factor 1 (EBF1) is associated with cholangiocarcinoma progression

DNA hypermethylation in a promoter region causes gene silencing via epigenetic changes. We have previously reported that early B cell factor 1 (EBF1) was down-regulated in cholangiocarcinoma (CCA) tissues and related to tumor progression. Thus, we hypothesized that the DNA hypermethylation of EBF1 promoter would suppress EBF1 expression in CCA and induce its progression. In this study, the DNA methylation status of EBF1 and mRNA expression levels were analyzed in CCA and normal bile duct (NBD) tissues using a publicly available database of genome-wide association data. The results showed that the DNA methylation of EBF1 promoter region was significantly increased in CCA tissues compared with those of NBD. The degree of methylation was negatively correlated with EBF1 mRNA expression levels. Using methylation-specific PCR technique, the DNA methylation rates of EBF1 promoter region were investigated in CCA tissues (n=72). CCA patients with high methylation rates of EBF1 promoter region in the tumor tissues (54/72) had a poor prognosis. Higher methylation rates of EBF1 promoter region have shown in all CCA cell lines than that of an immortal cholangiocyte cell line (MMNK1). Upon treatment with the DNA methyltransferase inhibitor 5-Aza-dC, increased EBF1 expression levels and reduced DNA methylation rates were observed in CCA cells. Moreover, restoration of EBF1 expression in CCA cells led to inhibition of cell growth, migration and invasion. In addition, RNA sequencing analysis suggested that EBF1 is involved in suppression of numerous pathways in cancer. Taken together, DNA hypermethylation in the EBF1 promoter region suppresses EBF1 expression and induces CCA progression with aggressive clinical outcomes.

Effects of selenium intake on the expression of prostaglandin-endoperoxide synthase 2 (cyclooxygenase-2) and matrix metallopeptidase-9 genes in the coronary artery disease: Selenegene study, a double-blind randomized controlled trial

BACKGROUND

The oxidative stress is regarded as one of the main contributors to the health problem. Cyclooxygenase-2 (COX-2) and matrix metallopeptidase-9 (MMP-9) are two of the important genes that are reported to be involved in the cardiovascular disease (CVD) development in the molecular and genetic association studies. The aim of this study was to evaluate the level of expression of COX-2 and MMP-9 after selenium supplementation in patients with coronary artery disease (CAD).

METHODS

In this sub-study of Selenegene study, subjects were randomly divided into groups, 19 subjects who received selenium and 22 patients with CAD who received placebo. Patients received either 200-mg selenium yeast tablets or placebo tablets after a meal, once daily for 60 days. The messenger ribonucleic acid (mRNA) levels of the selenium and prostaglandin-endoperoxide synthase 2 (PTGS2) (COX-2) and MMP-9 genes products were determined before and after the study.

RESULTS

In this sub-study, 41 Iranian patients with CVD were enrolled (placebo group: n = 22, selenium intervention: n = 19). Fasting blood sugar (FBS) was higher among placebo group than selenium group (93.4 ± 12.7 vs. 124.4 ± 40.6 mg/dl, P = 0.03). Triglyceride (TG) level was higher among selenium group versus placebo group (123.3 ± 34.0 vs. 184.8 ± 69.4 mg/dl, P = 0.006). The data analysis demonstrated that the expression of MMP-9 and COX-2 genes did not change significantly in both selenium and placebo groups.

CONCLUSION

This study showed a positive association between the expression of MMP-9 and COX-2 in the patients with CAD who received selenium but not the placebo groups. Yet, these findings need to be confirmed in further details and expanded sample size.

Bone-on-a-chip: microfluidic technologies and microphysiologic models of bone tissue

Bone is an active organ that continuously undergoes an orchestrated process of remodeling throughout life. Bone tissue is uniquely capable of adapting to loading, hormonal, and other changes happening in the body, as well as repairing bone that becomes damaged to maintain tissue integrity. On the other hand, diseases such as osteoporosis and metastatic cancers disrupt normal bone homeostasis leading to compromised function. Historically, our ability to investigate processes related to either physiologic or diseased bone tissue has been limited by traditional models that fail to emulate the complexity of native bone. Organ-on-a-chip models are based on technological advances in tissue engineering and microfluidics, enabling the reproduction of key features specific to tissue microenvironments within a microfabricated device. Compared to conventional in-vitro and in-vivo bone models, microfluidic models, and especially organs-on-a-chip platforms, provide more biomimetic tissue culture conditions, with increased predictive power for clinical assays. In this review, we will report microfluidic and organ-on-a-chip technologies designed for understanding the biology of bone as well as bone-related diseases and treatments. Finally, we discuss the limitations of the current models and point toward future directions for microfluidics and organ-on-a-chip technologies in bone research.

Intraductal Papillary Neoplasm of Bile Duct: Updated Clinicopathological Characteristics and Molecular and Genetic Alterations

Intraductal papillary neoplasm of the bile duct (IPNB), a pre-invasive neoplasm of the bile duct, is being established pathologically as a precursor lesion of invasive cholangiocarcinoma (CCA), and at the time of surgical resection, approximately half of IPNBs show stromal invasion (IPNB associated with invasive carcinoma). IPNB can involve any part of the biliary tree. IPNB shows grossly visible, exophytic growth in a dilated bile duct lumen, with histologically villous/papillary neoplastic epithelia with tubular components covering fine fibrovascular stalks. Interestingly, IPNB can be classified into four subtypes (intestinal, gastric, pancreatobiliary and oncocytic), similar to intraductal papillary mucinous neoplasm of the pancreas (IPMN). IPNBs are classified into low-grade and high-grade based on lining epithelial features. The new subclassification of IPNB into types 1 (low-grade dysplasia and high-grade dysplasia with regular architecture) and 2 (high-grade dysplasia with irregular architecture) proposed by the Japan–Korea pathologist group may be useful in the clinical field. The outcome of post-operative IPNBs is more favorable in type 1 than type 2. Recent genetic studies using next-generation sequencing have demonstrated the existence of several groups of mutations of genes: (i) IPNB showing mutations in KRAS, GNAS and RNF43 belonged to type 1, particularly the intestinal subtype, similar to the mutation patterns of IPMN; (ii) IPNB showing mutations in CTNNB1 and lacking mutations in KRAS, GNAS and RNF43 belonged to the pancreatobiliary subtype but differed from IPMN. IPNB showing mutation of TP53, SMAD4 and PIK3CA might reflect complicated and other features characterizing type 2. The recent recognition of IPNBs may facilitate further clinical and basic studies of CCA with respect to the pre-invasive and early invasive stages.

Translating Biomarkers of Cholangiocarcinoma for Theranosis: A Systematic Review

Cholangiocarcinoma (CCA) is a rare disease with poor outcomes and limited research efforts into novel treatment options. A systematic review of CCA biomarkers was undertaken to identify promising biomarkers that may be used for theranosis (therapy and diagnosis). MEDLINE/EMBASE databases (1996-2019) were systematically searched using two strategies to identify biomarker studies of CCA. The PANTHER Go-Slim classification system and STRING network version 11.0 were used to interrogate the identified biomarkers. The TArget Selection Criteria for Theranosis (TASC-T) score was used to rank identified proteins as potential targetable biomarkers for theranosis. The following proteins scored the highest, CA9, CLDN18, TNC, MMP9, and EGFR, and they were evaluated in detail. None of these biomarkers had high sensitivity or specificity for CCA but have potential for theranosis. This review is unique in that it describes the process of selecting suitable markers for theranosis, which is also applicable to other diseases. This has highlighted existing validated markers of CCA that can be used for active tumor targeting for the future development of targeted theranostic delivery systems. It also emphasizes the relevance of bioinformatics in aiding the search for validated biomarkers that could be repurposed for theranosis.

Lipoproteins-Nanocarriers as a Promising Approach for Targeting Liver Cancer: Present Status and Application Prospects

The prevalence of liver cancer is increasing over the years and it is the fifth leading cause of mortality worldwide. The intrusive features and burden of low survival rate make it a global health issue in both developing and developed countries. The recommended chemotherapy drugs for patients in the intermediate and advanced stages of various liver cancers yield a low response rate due to the nonspecific nature of drug delivery, thus warranting the search for new therapeutic strategies and potential drug delivery carriers. There are several new drug delivery methods available to ferry the targeted molecules to the specific biological environment. In recent years, the nano assembly of lipoprotein moieties (lipidic nanoparticles) has emerged as a promising and efficiently tailored drug delivery system in liver cancer treatment. This increased precision of nano lipoproteins conjugates in chemotherapeutic targeting offers new avenues for the treatment of liver cancer with high specificity and efficiency. This present review is focused on concisely outlining the knowledge of liver cancer diagnosis, existing treatment strategies, lipoproteins, their preparation, mechanism and their potential application in the treatment of liver cancer.

Prostaglandin D2 stimulates phenotypic changes in vascular smooth muscle cells

Since chronic inflammation is associated with the pathogenesis of atherosclerosis, inflammatory cytokines might contribute to the phenotypic modulation of vascular smooth muscle cells (VSMCs). Tumor necrosis factor α (TNFα) facilitated the transformation of contractile VSMCs to the synthetic phenotype, as determined by the expression of marker proteins and a collagen gel contraction assay. Western blot analysis and a cyclooxygenase-2 (COX2) promoter assay revealed that TNFα stimulation resulted in the induction of COX2. The overexpression, silencing, or pharmacological inhibition of COX2 significantly affected TNFα-induced phenotypic conversion, and of the tested prostaglandins, only PGD₂ significantly induced phenotypic conversion. ERK was significantly activated by PGD₂ stimulation, and the pharmacological inhibition of ERK blocked the PGD₂-induced phenotypic conversion of VSMCs. However, antagonists or agonists of PGD₂ receptors did not affect VSMC conversion. In contrast, spontaneously dehydrated forms of PGD₂, such as PGJ₂, Δ¹²-PGJ₂, and 15-d-PGJ₂, strongly induced phenotypic conversion. A reporter gene assay showed that TNFα, PGD₂, and 15-d-PGJ₂ significantly activated the peroxisome proliferator-responsive element (PPRE) promoter. In addition, the overexpression or silencing of peroxisome proliferator-activated receptor δ (PPARδ) significantly influenced 15-d-PGJ₂-induced phenotypic conversion. Finally, atherosclerotic neointima formation was significantly suppressed in mice lacking TNFα. In addition, mice fed celecoxib exhibited complete inhibition of carotid artery ligation-induced neointima formation. This study shows that PGD₂ regulates the phenotypic conversion of VSMCs by generating an endogenous ligand of PPAR, and that this leads to neointima formation in occlusive arterial disease.

A lipid compound that stimulates muscle cells to change type is instrumental in the development of arterial plaque formation in artherosclerosis. Sun Sik Bae at Pusan National University School of Medicine in Gyungnam, South Korea, and co-workers examined the role of inflammatory proteins in the development of artherosclerosis, a condition involving the build-up of scar tissue or ‘plaques’ on artery walls. The behavior of vascular smooth muscle cells (VSMCs) is crucial to plaque development because, triggered by inflammatory protein activity, the cells switch from contractile-type cells to faster proliferating VSMCs, accelerating plaque growth. The team found that a compound called prostaglandin D₂, a direct by-product of inflammatory protein behavior, together with a protein regulating gene expression, are key factors triggering this VSMC change. These insights may prove valuable in developing therapies for artherosclerosis.

Development of A New Mouse Model for Intrahepatic Cholangiocellular Carcinoma: Accelerating Functions of Pecam-1

Due to the lack of suitable in-vivo models, the etiology of intrahepatic cholangiocellular carcinoma (ICC) is poorly understood. We previously showed the involvement of platelet endothelial cell adhesion molecule-1 (Pecam-1/CD31) in acute liver damage. Here, we developed a model of ICC using thioacetamide (TAA) in drinking water of wild-type (WT)-mice and Pecam-1-knock-out (KO)-mice. Gross inspection and microscopy revealed liver-cirrhosis and ICC in both groups after 22 weeks of TAA. The severity of cirrhosis and ICC (Ck-19-positive) was reduced in Pecam-1 KO mice (stage-4 cirrhosis in WT vs. stage-3 in KO mice). Tumor networks (accompanied by neutrophils) were predominantly located in portal areas, with signs of epithelial-to-mesenchymal transition (EMT). In serum, TAA induced an increase in hepatic damage markers, with lower levels in Pecam-1 null mice. With qPCR of liver, elevated expression of Pecam-1 mRNA was noted in WT mice, in addition to Icam-1, EpCam, cytokines, cMyc, and Mmp2. Thereby, levels of EpCAM, cytokines, cMyc, and Mmp2 were significantly lower in Pecam-1 null mice. Lipocalin-2 and Ccl5 were elevated significantly in both WT and Pecam-1 null mice after TAA administration. Also, EMT marker Wnt5a (not Twist-1) was increased in both groups after TAA. We present a highly reproducible mouse model for ICC and show protective effects of Pecam-1 deficiency.

Microfluidic platform for studying osteocyte mechanoregulation of breast cancer bone metastasis

Bone metastasis is a common, yet serious, complication of breast cancer. Breast cancer cells that extravasate from blood vessels to the bone devastate bone quality by interacting with bone cells and disrupting the bone remodeling balance. Although exercise is often suggested as a cancer intervention strategy and mechanical loading during exercise is known to regulate bone remodeling, its role in preventing bone metastasis remains unknown. We developed a novel in vitro microfluidic tissue model to investigate the role of osteocytes in the mechanical regulation of breast cancer bone metastasis. Metastatic MDA-MB-231 breast cancer cells were cultured inside a 3D microfluidic lumen lined with human umbilical vein endothelial cells (HUVECs), which is adjacent to a channel seeded with osteocyte-like MLO-Y4 cells. Physiologically relevant oscillatory fluid flow (OFF) (1 Pa, 1 Hz) was applied to mechanically stimulate the osteocytes. Hydrogel-filled side channels in-between the two channels allowed real-time, bi-directional cellular signaling and cancer cell extravasation over 3 days. The applied OFF was capable of inducing intracellular calcium responses in osteocytes (82.3% cells responding with a 3.71 fold increase average magnitude). Both extravasation distance and percentage of extravasated side-channels were significantly reduced with mechanically stimulated osteocytes (32.4% and 53.5% of control, respectively) compared to static osteocytes (102.1% and 107.3% of control, respectively). This is the first microfluidic device that has successfully integrated stimulatory bone fluid flow, and demonstrated that mechanically stimulated osteocytes reduced breast cancer extravasation. Future work with this platform will determine the specific mechanisms involved in osteocyte mechanoregulation of breast cancer bone metastasis, as well as other types of cancer metastasis and diseases.

Triumph and tumult of matrix metalloproteinases and their crosstalk with eicosanoids in cancer

Cancer development and metastasis are associated to perturbation in metabolic functions of tumor cells and surrounding inflammatory and stromal cell responses. Eicosanoids and lipid mediators, in this regard, attract potential attention during cancer development. Eicosanoids, which include prostaglandin, prostacyclin, thromboxane, and leukotriene, are synthesized from arachidonic acid when cells are stimulated by stress, cytokines, or other growth factors. However, the underlying mechanism of eicosanoids in cancer development, specially their interactions with proto-oncogene factors in tumor microenvironment, remain unexplored. On the other hand, matrix metalloproteinases (MMPs) are a group of zinc-dependent endopeptidases which are involved in degradation of different extracellular matrix (ECM) proteins. MMPs are associated with different physiological responses, including embryogenesis, vasculogenesis, and cellular remodeling, as well as different disease pathogenesis. Induced MMP responses are especially associated with cancer metastasis and secondary tumor development through proteolytic cleavage of several ECM and non-ECM proteins. Although both eicosanoids and MMPs are involved with cancer progression and metastasis, the interrelation between these two molecules are less explored. The present review discusses relevant studies that connect eicosanoids and MMPs and highlight the crosstalk between them offering novel therapeutic approach in cancer treatment.

Stimulation of Peritoneal Mesothelial Cells to Secrete Matrix Metalloproteinase-9 (MMP-9) by TNF-α: A Role in the Invasion of Gastric Carcinoma Cells

It has recently been recognized that inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), upregulate the secretion of matrix metalloproteinase-9 (MMP-9) from cancer cells and thereby promote peritoneal dissemination. In this study, we found that TNF-α also stimulated peritoneal mesothelial cells to secrete MMP-9 as assessed by zymography. MMP-9 gene expression in mesothelial cells induced by TNF-α was confirmed by quantitative RT-PCR analysis. We then utilized the reconstituted artificial mesothelium, which was composed of a monolayer of mesothelial cells cultured on a Matrigel layer in a Boyden chamber system, to examine the effects of TNF-α on carcinoma cell invasion. The transmigration of MKN1 human gastric carcinoma cells through the reconstituted mesothelium was promoted by TNF-α in a dose-dependent manner. The increased MKN1 cell migration was partially inhibited by the anti-α3 integrin antibody, indicating that the invasion process involves an integrin-dependent mechanism. Finally, we observed that the invasion of MMP-9-knockdown MKN1 cells into Matrigel membranes was potentiated by the exogenous addition of purified proMMP-9. These results suggest that TNF-α-induced MMP-9 secretion from mesothelial cells plays an important role in the metastatic dissemination of gastric cancer.

Molecular Mechanisms Driving Cholangiocarcinoma Invasiveness: An Overview

The acquisition of invasive functions by tumor cells is a first and crucial step toward the development of metastasis, which nowadays represents the main cause of cancer-related death. Cholangiocarcinoma (CCA), a primary liver cancer originating from the biliary epithelium, typically develops intrahepatic or lymph node metastases at early stages, thus preventing the majority of patients from undergoing curative treatments, consistent with their very poor prognosis. As in most carcinomas, CCA cells gradually adopt a motile, mesenchymal-like phenotype, enabling them to cross the basement membrane, detach from the primary tumor, and invade the surrounding stroma. Unfortunately, little is known about the molecular mechanisms that synergistically orchestrate this proinvasive phenotypic switch. Autocrine and paracrine signals (cyto/chemokines, growth factors, and morphogens) permeating the tumor microenvironment undoubtedly play a prominent role in this context. Moreover, a number of recently identified signaling systems are currently drawing attention as putative mechanistic determinants of CCA cell invasion. They encompass transcription factors, protein kinases and phosphatases, ubiquitin ligases, adaptor proteins, and miRNAs, whose aberrant expression may result from either stochastic mutations or the abnormal activation of upstream pro-oncogenic pathways. Herein we sought to summarize the most relevant molecules in this field and to discuss their mechanism of action and potential prognostic relevance in CCA. Hopefully, a deeper knowledge of the molecular determinants of CCA invasiveness will help to identify clinically useful biomarkers and novel druggable targets, with the ultimate goal to develop innovative approaches to the management of this devastating malignancy.

Functions of chemokines in the perineural invasion of tumors (Review)

The perineural invasion (PNI) of malignant tumors is a form of tumor progression in which cancer cells encroach along nerves. PNI hinders curative resection. Residual tumor cells in or around nerves can bring about local recurrence, infiltration and metastasis. This behavior is usually associated with a poor clinical prognosis. Therefore, it is necessary to investigate novel ligand-receptor crosstalk between nerves and tumor cells that promote the process of PNI. Chemokines are regarded as one of pivotal factors involved in the process of PNI. The present review collates information provided by previous studies with regard to the role of chemokines in PNI. The study presents a definition of PNI in cancer, generalizes the biological characteristics and the expression of chemokines and their receptors in cancer types associated with PNI, and discusses the underlying molecular mechanisms of chemokines, the reciprocal interactions between chemokines and other factors in PNI, and the interconnectivity of the microenvironment and chemokines. The aim of the review is to thoroughly illustrate the molecular cues of chemokines in cancer with PNI and to identify novel antitumor targets.

Emerging molecular target antagonists for the treatment of biliary tract cancer

INTRODUCTION

Biliary tract cancers (BTCs) are a heterogeneous group of cancers, characterized by low incidence but poor prognosis. Even after complete surgical resection for early stage, relapse is frequent and the lack of effective treatments contributes to the dismal prognosis. To date, the only standard treatment in first-line is cisplatin/gemcitabine combination, whereas no standard in 2nd-line has been defined. Hence, the current goal is to better understand the biology of BTCs, discovering new treatment methods and improving clinical outcomes. Areas covered: The development of next-generation-sequencing has unveiled the picture of the molecular signatures characterizing BTCs, leading to the identification of actionable mutations in biomarker-driven clinical trials. In this review we will cover the genetic landscape of BTC, focusing on the efficacy of existing treatments. Furthermore, we will discuss emerging molecular targets and evaluate the findings of pre-clinical studies. Finally, the encouraging results of clinical trials involving targeted therapies or immunotherapy will be reviewed. Expert opinion: FGFR fusion rearrangements and IDH1 or IDH2 mutations are the most promising targeted treatments under evaluation. In addition, innovative trial design will allow to offer a chance for tailored medicine to infrequent subgroups of BTCs patients based on their molecular features rather than their histology.

Desmoplastic Tumor Microenvironment and Immunotherapy in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a dismal disease which often is diagnosed at a late stage where the tumor is locally advanced, metastatic, and, as a result, is associated with low resectability. The heterogeneity of this cancer type is a major reason why the majority of patients fail to respond to therapy, and surgery remains their only curative option. Among patients who undergo surgical intervention, such tumors typically recur in 50% of cases within 1year. Thus, CCA is among the most aggressive and chemoresistant malignancies. CCA is characterized by marked tumor reactive stroma, a fibrogenic connective tissue which surrounds and infiltrates the tumor epithelium. This desmoplastic environment presents a clinical challenge, limiting drug delivery and supporting the growth of the tumor mass. In this review we attempt to highlight key pathways involved in cell to cell communication between the tumor epithelium and stroma, the immune components, and opportunities for novel strategies to improve patient outcome.

Imbalanced adaptive responses associated with microsatellite instability in cholangiocarcinoma

The adaptive response of the genome protection mechanism occurs in cells when exposed to genotoxic stress due to the overproduction of free radicals via inflammation and infection. In such circumstances, cells attempt to maintain health via several genome protection mechanisms. However, evidence is increasing that this adaptive response may have deleterious effect; a reduction of antioxidant enzymes and/or imbalance in the DNA repair system generates microsatellite instability (MSI), which has procarcinogenic implications. Therefore, the present study hypothesized that MSI caused by imbalanced responses of antioxidant enzymes and/or DNA repair enzymes as a result of oxidative/nitrative stress arising from the inflammatory response is involved in liver fluke-associated cholangiocarcinogenesis. The present study investigated this hypothesis by identifying the expression patterns of antioxidant enzymes, including superoxide dismutase 2 (SOD2) and catalase (CAT), and DNA repair enzymes, including alkyladenine DNA glycosylase (AAG), apurinic endonuclease (APE) and DNA polymerase β (DNA pol β). In addition, the activities of the antioxidant enzymes, SOD2 and CAT, were examined in human cholangiocarcinoma (CCA) tissues using immunohistochemical staining. MSI was also analyzed in human CCA tissues. The resulting data demonstrated that the expression levels of the SOD2 and CAT enzymes decreased. The activities of SOD2 and CAT decreased significantly in the CCA tissues, compared with the hepatic tissue of cadaveric donors. In the DNA repairing enzymes, it was found that the expression levels of AAG and DNA pol β enzymes increased, whereas the expression of APE decreased. In addition, it was found that MSI-high was present in 69% of patients, whereas MSI-low was present in 31% of patients, with no patients classified as having microsatellite stability. In the patients, a MSI-high was correlated with poor prognosis, indicated by a shorter survival rate. These results indicated that the reduction of antioxidant enzymes and adaptive imbalance of base excision repair enzymes in human CCA caused MSI, and may be associated with the progression of cancer.

Cyclooxygenase-2 in tumor-associated macrophages promotes metastatic potential of breast cancer cells through Akt pathway

Tumor-associated macrophages (TAMs) promote cancer development and progression by releasing various cytokines and chemokines. Previously, we have found that the number of COX-2+ TAMs was associated with lymph node metastasis in breast cancer. However, the mechanism remains enigmatic. In this study, we show that COX-2 in breast TAMs enhances the metastatic potential of breast cancer cells. COX-2 in TAMs induces MMP-9 expression and promotes epithelial-mesenchymal transition (EMT) in breast cancer cells. In addition, COX-2/PGE2 induces IL-6 release in macrophages. Furthermore, we find that the activation of Akt pathway in cancer cells is crucial for the pro-metastatic effect of COX-2+ TAMs by regulating MMP-9 and EMT. These findings indicate that TAMs facilitate breast cancer cell metastasis through COX-2-mediated intercellular communication.

Inhibition of the Biosynthesis of Prostaglandin E2 By Low-Dose Aspirin: Implications for Adenocarcinoma Metastasis

Meta-analyses have demonstrated that low-dose aspirin reduces the risk of developing adenocarcinoma metastasis, and when colon cancer is detected during aspirin treatment, there is a remarkable 83% reduction in risk of metastasis. As platelets participate in the metastatic process, the antiplatelet action of low-dose aspirin likely contributes to its antimetastatic effect. Cycloxooxygenase-2 (COX-2)-derived prostaglandin E₂ (PGE₂) also contributes to metastasis, and we addressed the hypothesis that low-dose aspirin also inhibits PGE₂ biosynthesis. We show that low-dose aspirin inhibits systemic PGE₂ biosynthesis by 45% in healthy volunteers (P < 0.0001). Aspirin is found to be more potent in colon adenocarcinoma cells than in the platelet, and in lung adenocarcinoma cells, its inhibition is equivalent to that in the platelet. Inhibition of COX by aspirin in colon cancer cells is in the context of the metastasis of colon cancer primarily to the liver, the organ exposed to the same high concentrations of aspirin as the platelet. We find that the interaction of activated platelets with lung adenocarcinoma cells upregulates COX-2 expression and PGE₂ biosynthesis, and inhibition of platelet COX-1 by aspirin inhibits PGE₂ production by the platelet-tumor cell aggregates. In conclusion, low-dose aspirin has a significant effect on extraplatelet cyclooxygenase and potently inhibits COX-2 in lung and colon adenocarcinoma cells. This supports a hypothesis that the remarkable prevention of metastasis from adenocarcinomas, and particularly from colon adenocarcinomas, by low-dose aspirin results from its effect on platelet COX-1 combined with inhibition of PGE₂ biosynthesis in metastasizing tumor cells. Cancer Prev Res; 9(11); 855-65. ©2016 AACR.

Cholangiocarcinoma: Present Status and Molecular Aspects of Diagnosis

Cholangiocarcinomas are neoplasms that involve the epithelial cells of the bile duct, also known as cholangiocytes. This disease is difficult to diagnose early, as most symptoms present late in the disease. In addition, the specific anatomic position can cause periductal extension and result in a very low radical excision rate and a very poor prognosis. Improved understanding of the features underlying the onset of cholangiocarcinoma and its carcinogenic mechanism may lead to early diagnosis and better prognosis. With the development of molecular biology, much has been learned about oncogenes, tumor-suppressor genes, DNA methylation, microRNAs, and the molecular mechanisms of tumor invasion and metastasis. Based on our research and others, this review article will discuss the current status and prospects of early diagnosis of cholangiocarcinoma.

Multiple cellular origins and molecular evolution of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy associated with unfavorable prognosis and for which no effective treatments are available. Its molecular pathogenesis is poorly understood. Genome-wide sequencing and high-throughput technologies have provided critical insights into the molecular basis of ICC while sparking a heated debate on the cellular origin. Cancer exhibits variabilities in origin, progression and cell biology. Recent evidence suggests that ICC has multiple cellular origins, including differentiated hepatocytes; intrahepatic biliary epithelial cells (IBECs)/cholangiocytes; pluripotent stem cells, such as hepatic stem/progenitor cells (HPCs) and biliary tree stem/progenitor cells (BTSCs); and peribiliary gland (PBG). However, both somatic mutagenesis and epigenomic features are highly cell type-specific. Multiple cellular origins may have profoundly different genomic landscapes and key signaling pathways, driving phenotypic variation and thereby posing significant challenges to personalized medicine in terms of achieving the optimal drug response and patient outcome. Considering this information, we have summarized the latest experimental evidence and relevant literature to provide an up-to-date view of the cellular origin of ICC, which will contribute to establishment of a hierarchical model of carcinogenesis and allow for improvement of the anatomical-based classification of ICC. These new insights have important implications for both the diagnosis and treatment of ICC patients.

Epidermal growth factor-induced cyclooxygenase-2 enhances head and neck squamous cell carcinoma metastasis through fibronectin up-regulation

Epidermal growth factor receptor (EGFR) activation is a major cause of metastasis in many cancers, such as head and neck squamous cell carcinoma (HNSCC). However, whether the induction of cyclooxygenase-2 (COX-2) mediates EGF-enhanced HNSCC metastasis remains unclear. Interestingly, we found that EGF induced COX-2 expression mainly in HNSCC. The tumor cell transformation induced by EGF was repressed by COX-2 knockdown, and this repression was reversed by simultaneously treating the cells with EGF and prostaglandin E₂ (PGE₂). The down-regulation of COX-2 expression or inhibition of COX-2 activity significantly blocked EGF enhancement of cell migration and invasion, but the addition of PGE₂ compensated for this inhibitory effect in COX-2-knockdown cells. COX-2 depletion inhibited EGF-induced matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-9, and fibronectin expression and Rac1/cdc42 activation. The inhibitory effect of COX-2 depletion on MMPs and the fibronectin/Rac1/cdc42 axis were reversed by co-treatment with PGE₂. Furthermore, depletion of fibronectin impeded the COX-2-enhanced binding of HNSCC cells to endothelial cells and tumor cells metastatic seeding of the lungs. These results demonstrate that EGF-induced COX-2 expression enhances HNSCC metastasis via activation of the fibronectin signaling pathway. The inhibition of COX-2 expression and activation may be a potential strategy for the treatment of EGFR-mediated HNSCC metastasis.

Co-targeting of Cyclooxygenase-2 and FoxM1 is a viable strategy in inducing anticancer effects in colorectal cancer cells

BACKGROUND

Cross-talk between deregulated signaling pathways in cancer cells causes uncontrolled growth and proliferation. These cancers cells become more aggressive and quickly develop resistance to therapy. Therefore targeting of these deregulated pathways simultaneously can result in efficient cell death of cancer cells. In this study we investigated co-expression of Cox-2 and FoxM1 in a cohort of colorectal carcinoma (CRC) samples and also examined whether inhibition of Cox-2 and FoxM1 simultaneously can lead to inhibition of cell viability and induction of apoptosis in colorectal cancer cell lines and in vivo xenografts.

METHODS

Protein expression of Cox-2 and FoxM1 was determined in a large cohort of 770 clinical CRC samples in a tissue micro-array format by immunohistochemistry. Cell death was measured using live dead assay. Apoptosis was measured by annexin V/PI dual staining. Immunoblotting was performed to examine the expression of proteins. Calcusyn software was utilized to estimate the synergistic doses using chou and Talalay method.

RESULTS

Co-expression of Cox-2 and FoxM1 was detected in 33.3 % (232/697) of CRC's and associated with an aggressive phenotype characterized by younger age (p = 0.0191), high proliferative index marker; Ki-67 (p = 0.004) and MMP-9 (p = 0.0116) as well as activation of AKT (p = 0.0214). In vitro, inhibition of FoxM1 and Cox-2 with pharmacological inhibitors; Thiostrepton and NS398 resulted in efficient down-regulation of FoxM1 and Cox-2 expression along with in-activation of AKT and inhibition of colony formation, invasion and migratory capability of CRC cells. In addition, there was also inhibition of cell viability and induction of apoptosis via the mitochondrial apoptotic pathway in CRC cell lines. Finally, treatment of CRC xenograft tumors in nude mice with combination of Cox-2 and FoxM1 inhibitors inhibited tumor growth significantly via down-regulation of Cox-2 and FoxM1 expression.

CONCLUSIONS

These findings demonstrate that co-expression of Cox-2 and FoxM1 might play a critical role in the pathogenesis of CRC. Therefore, targeting of these pathways simultaneously with sub toxic doses of pharmacological inhibitors can be a potential therapeutic approach for the treatment of this subset of CRC.

Lack of association between COX-2 8473T>C polymorphism and breast cancer risk: a meta-analysis

Aim of the study

Results of recent published studies on the association between the COX-2 8473T>C polymorphism and the risk of breast cancer have often been conflicting. To make a more precise estimation of the potential relationship, a meta-analysis was performed.

Material and methods

A total of seven case-control studies with 7,033 cases and 9,350 controls were included in the current meta-analysis through searching the databases of PubMed, Embase, and Cochrane Library (up to March 1^st, 2013). The odds ratio (OR) and 95% confidence interval (95% CI) were calculated to assess the strength of the association. The meta-analysis was conducted in a fixed/random effect model.

Results

We found no significant associations for all genetic models after all studies were pooled into the meta-analysis (for C vs. T: OR = 0.974, 95% CI: 0.906–1.047, p = 0.471; for CC vs. TT: OR = 0.957, 95% CI: 0.803–1.140, p = 0.62; for TC vs. TT: OR = 0.964, 95% CI: 0.881–1.055, p = 0.421; for CC + TC vs. TT: OR = 0.963, 95% CI: 0.880–1.053, p = 0.406; for CC vs. TT + TC: OR = 0.978, 95% CI: 0.831–1.15, p = 0.788). We also observed no obvious associations in the subgroup analyses by ethnicity (Caucasian) and source of controls (population based, PB) for all genetic models.

Conclusions

Current evidence suggests that the COX-2 8473T>C polymorphism is not associated with breast cancer risk.

AM404 inhibits NFAT and NF-κB signaling pathways and impairs migration and invasiveness of neuroblastoma cells

N-Arachidonoylphenolamine (AM404), a paracetamol lipid metabolite, is a modulator of the endocannabinoid system endowed with pleiotropic activities. AM404 is a dual agonist of the Transient Receptor Potential Vanilloid type 1 (TRPV1) and the Cannabinoid Receptor type 1 (CB₁) and inhibits anandamide (AEA) transport and degradation. In addition, it has been shown that AM404 also exerts biological activities through TRPV1- and CB₁ -independent pathways. In the present study we have investigated the effect of AM404 in the NFAT and NF-κB signaling pathways in SK-N-SH neuroblastoma cells. AM404 inhibited NFAT transcriptional activity through a CB₁- and TRPV1-independent mechanism. Moreover, AM404 inhibited both the expression of COX-2 at transcriptional and post-transcriptional levels and the synthesis of PGE₂. AM404 also inhibited NF-κB activation induced by PMA/Ionomycin in SK-N-SH cells by targeting IKKβ phosphorylation and activation. We found that Cot/Tlp-2 induced NFAT and COX-2 transcriptional activities were inhibited by AM404. NFAT inhibition paralleled with the ability of AM404 to inhibit MMP-1, -3 and -7 expression, cell migration and invasion in a cell-type specific dependent manner. Taken together, these data reveal that paracetamol, the precursor of AM404, can be explored not only as an antipyretic and painkiller drug but also as a co-adjuvant therapy in inflammatory and cancer diseases.

Cholangiocarcinoma: Biology, Clinical Management, and Pharmacological Perspectives

Cholangiocarcinoma (CCA), or tumor of the biliary tree, is a rare and heterogeneous group of malignancies associated with a very poor prognosis. Depending on their localization along the biliary tree, CCAs are classified as intrahepatic, perihilar, and distal, and these subtypes are now considered different entities that differ in tumor biology, the staging system, management, and prognosis. When diagnosed, an evaluation by a multidisciplinary team is essential; the team must decide on the best therapeutic option. Surgical resection of tumors with negative margins is the best option for all subtypes of CCA, although this is only achieved in less than 50% of cases. Five-year survival rates have increased in the recent past owing to improvements in imaging techniques, which permits resectability to be predicted more accurately, and in surgery. Chemotherapy and radiotherapy are relatively ineffective in treating nonoperable tumors and the resistance of CCA to these therapies is a major problem. Although the combination of gemcitabine plus platinum derivatives is the pharmacological treatment most widely used, to date there is no standard chemotherapy, and new combinations with targeted drugs are currently being tested in ongoing clinical trials. This review summarizes the biology, clinical management, and pharmacological perspectives of these complex tumors.

WTAP regulates migration and invasion of cholangiocarcinoma cells

BACKGROUND

Wilms' tumor 1-associating protein (WTAP) is a nuclear protein that has been associated with the regulation of proliferation and apoptosis. Although its dynamic expression and physiological functions in vascular cells have been reported, its expression and roles in cholangiocarcinoma cells are poorly characterized.

METHODS

To examine the expression of WTAP in patient tissues, we performed immunohistochemistry. To examine motility of cholangiocarcinoma cells, we employed Boyden chamber, wound healing and Matrigel invasion assays, and a liver xenograft model.

RESULTS

Immunohistochemistry in patient tissues showed WTAP overexpression in cholangiocarcinoma tissues and correlation of WTAP expression with metastasis of cholangiocarcinoma cells. Overexpression or knockdown of WTAP significantly increased or decreased the motility of cholangiocarcinoma cells. Moreover, WTAP overexpression or knockdown significantly increased or decreased tumorigenicity of cholangiocarcinoma cells in an orthotopic xenograft model. Furthermore, microarray study showed that WTAP induce the expressions of MMP7, MMP28, cathepsin H and Muc1.

CONCLUSION

WTAP is overexpressed in cholangiocarcinoma and regulates motility of cholangiocarcinoma cells.

Oncogenic activity of retinoic acid receptor γ is exhibited through activation of the Akt/NF-κB and Wnt/β-catenin pathways in cholangiocarcinoma

Aberrant expression and function of retinoic acid receptor γ (RARγ) are often involved in the progression of several cancers. However, the role of RARγ in cholangiocarcinoma (CCA), chemoresistant bile duct carcinoma with a poor prognosis, remains unclear. In the present study, we found that RARγ was frequently overexpressed in human CCA specimens. Its overexpression was associated with poor differentiation, lymph node metastasis, high serum carbohydrate antigen 19-9 level, and poor prognosis of CCA. Downregulation of RARγ reduced CCA cell proliferation, migration, invasion, and colony formation ability in vitro and tumorigenic potential in nude mice. RARγ knockdown resulted in upregulation of cell cycle inhibitor P21, as well as downregulation of cyclin D1, proliferating cell nuclear antigen, and matrix metallopeptidase 9, in parallel with suppression of the Akt/NF-κB pathway. Furthermore, overexpression of RARγ contributed to the multidrug chemoresistance of CCA cells, at least in part due to upregulation of P glycoprotein via activation of the Wnt/β-catenin pathway. Molecular mechanism studies revealed that RARγ interacted with β-catenin and led to β-catenin nuclear translocation. Taken together, our results suggested that RARγ plays an important role in the proliferation, metastasis, and chemoresistance of CCA through simultaneous activation of the Akt/NF-κB and Wnt/β-catenin pathways, serving as a potential molecular target for CCA treatment.

Oncogenic activity of retinoic acid receptor γ is exhibited through activation of the Akt/NF-κB and Wnt/β-catenin pathways in cholangiocarcinoma

Aberrant expression and function of retinoic acid receptor γ (RARγ) are often involved in the progression of several cancers. However, the role of RARγ in cholangiocarcinoma (CCA), chemoresistant bile duct carcinoma with a poor prognosis, remains unclear. In the present study, we found that RARγ was frequently overexpressed in human CCA specimens. Its overexpression was associated with poor differentiation, lymph node metastasis, high serum carbohydrate antigen 19-9 level, and poor prognosis of CCA. Downregulation of RARγ reduced CCA cell proliferation, migration, invasion, and colony formation ability in vitro and tumorigenic potential in nude mice. RARγ knockdown resulted in upregulation of cell cycle inhibitor P21, as well as downregulation of cyclin D1, proliferating cell nuclear antigen, and matrix metallopeptidase 9, in parallel with suppression of the Akt/NF-κB pathway. Furthermore, overexpression of RARγ contributed to the multidrug chemoresistance of CCA cells, at least in part due to upregulation of P glycoprotein via activation of the Wnt/β-catenin pathway. Molecular mechanism studies revealed that RARγ interacted with β-catenin and led to β-catenin nuclear translocation. Taken together, our results suggested that RARγ plays an important role in the proliferation, metastasis, and chemoresistance of CCA through simultaneous activation of the Akt/NF-κB and Wnt/β-catenin pathways, serving as a potential molecular target for CCA treatment.

Tanshinone II--a inhibits angiogenesis through down regulation of COX-2 in human colorectal cancer

Angiogenesis plays a significant role in colorectal cancer (CRC) and cyclooxygenase-2 (COX-2) appears to be involved with multiple aspects of CRC angiogenesis. Our aim was to investigate the inhibitory effects of Tan II-A (Tanshinone II-A, Tan II-A) on tumor growth in mice, as well as alteration of expression of COX-2 and VEGF in CRC. We established the mice xenograft model of C26 CRC cell line, and injected 0.5, 1, 2mg/kg of Tan II-A and 1mg/kg of 5-FU in respectively in vivo. Then, we assayed tumor weight and volume, and evaluated microvascular density and expression of VEGF. COX-2 promoter and COX-2 plasmids were transfected into HCT-116 cells, followed by detection of COX-2 promoter activity by chemiluminescence, and detection of COX-2 mRNA expression by fluorescence quantitative PCR. Taken together, the results showed Tan II-A could inhibit tumor growth and suppress the VEGF level in vivo. HCT-116 cell experiments showed marked inhibitory effects of Tan II-A on COX-2 and VEGF in a dose-dependent manner. The results indicate that Tan II-A can effectively inhibit tumor growth and angiogenesis of human colorectal cancer via inhibiting the expression level of COX-2 and VEGF.

The challenge of cholangiocarcinoma: dissecting the molecular mechanisms of an insidious cancer

Cholangiocarcinoma is a fatal cancer of the biliary epithelium and has an incidence that is increasing worldwide. Survival beyond a year of diagnosis is less than 5%, and therapeutic options are few. Known risk factors include biliary diseases such as primary sclerosing cholangitis and parasitic infestation of the biliary tree, but most cases are not associated with any of these underlying diseases. Numerous in vitro and in vivo models, as well as novel analytical techniques for human samples, are helping to delineate the many pathways implicated in this disease, albeit at a frustratingly slow pace. As yet, however, none of these studies has been translated into improved patient outcome and, overall, the pathophysiology of cholangiocarcinoma is still poorly understood. There remains an urgent need for new approaches and models to improve management of this insidious and devastating disease. In this review, we take a bedside-to-bench approach to discussing cholangiocarcinoma and outline research opportunities for the future in this field.

Different roles of inducible nitric oxide synthase and cyclooxygenase-2 in carcinogenesis and metastasis of intrahepatic cholangiocarcinoma

Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) have been implicated in chronic inflammatory conditions and carcinogenesis. However, little is known about the biological significance of iNOS and COX-2 in cholangiocarcinoma or its precursors or metastatic lesions. We examined iNOS and COX-2 immunohisotochemical expression in 40 biliary intraepithelial neoplasias, 134 primary intrahepatic cholangiocarcinoma cases, and 27 metastatic lymph nodes and analyzed the correlations with grade of atypia of biliary intraepithelial neoplasia, clinicopathological factors and outcomes of intrahepatic cholangiocarcinoma. iNOS and COX-2 expression was highly expressed in reactive epithelium and biliary intraepithelial neoplasia. In intrahepatic cholangiocarcinoma, lymphatic invasion and lymph node metastasis were significantly correlated with negative iNOS expression (P = .0002, P = .0324, respectively) and positive COX-2 expression (P = .0012, P = .0063, respectively). Vascular endothelial growth factor-C expression was associated with COX-2 expression (P = .0053), but not with iNOS expression. COX-2 expression in primary intrahepatic cholangiocarcinoma was higher than that in metastatic lymph nodes (P < .0001). COX-2-positive expression indicated a poor intrahepatic cholangiocarcinoma outcome (P = .0273). This study indicates that iNOS and COX-2 may play roles in carcinogenesis via biliary intraepithelial neoplasia, but play different roles in metastasis of intrahepatic cholangiocarcinoma. COX-2 may participate in a higher lymphatic invasion and metastasis via the vascular endothelial growth factor-C pathway.

Overexpression of enhancer of zeste homolog 2 and MUC1 may be related to malignant behaviour in intraductal papillary neoplasm of the bile duct

AIMS

  Intraductal papillary neoplasm of the bile duct (IPNB) usually has a favourable prognosis, but occasionally is associated with invasive carcinoma. Overexpression of the polycomb group protein enhancer of zeste homolog 2 (EZH2) is involved in the progression of malignant tumours. In this study, we examined the significance of EZH2 expression in IPNB and its association with clinicopathological features and the expression of p16(INK4a) , p53 and mucin core proteins.

METHODS AND RESULTS

  We examined immunohistochemically the expression of EZH2, p16(INK4a) , MUC mucin core proteins and p53 in 15 patients with IPNB without invasion, including the cystic variant [male/female ratio (M/F) = 9/6], and in 19 with IPNB associated with invasive carcinoma (M/F = 13/6). The expression levels of EZH2, p53 and MUC1 were significantly lower (P < 0.01), and of MUC6 were significantly higher (P < 0.05), in IPNB without invasion than in IPNB with invasion. Expression of EZH2 was significantly correlated with expression of MUC1 (P < 0.01) and inversely correlated with expression of MUC6 (P < 0.05). In cholangiocarcinoma cells (HuCTT-1 and TFK-1), knockdown of EZH2 and MUC1 by small interfering RNA decreased invasion and proliferation, whereas knockdown of MUC6 increased invasion.

CONCLUSIONS

  Overexpression of EZH2 may be associated with malignant behaviour in IPNB in parallel with up-regulated MUC1 expression and down-regulated MUC6 expression.

Epithelial-mesenchymal transition, a novel target of sulforaphane via COX-2/MMP2, 9/Snail, ZEB1 and miR-200c/ZEB1 pathways in human bladder cancer cells

Metastasis and recurrence of bladder cancer are the main reasons for its poor prognosis and high mortality rates. Because of its biological activity and high metabolic accumulation in urine, sulforaphane, a phytochemical exclusively occurring in cruciferous vegetables, has a powerful and specific potential for preventing bladder cancer. In this paper, sulforaphane is shown to significantly suppress a variety of biochemical pathways including the attachment, invasion, migration and chemotaxis motion in malignant transitional bladder cancer T24 cells. Transfection with cyclooxygenase-2 (COX-2) overexpression plasmid largely abolished inhibition of MMP2/9 expression as well as cell invasive capability by sulforaphane. Moreover, sulforaphane inhibited the epithelial-to-mesenchymal transition (EMT) process which underlies tumor cell invasion and migration mediated by E-cadherin induction through reducing transcriptional repressors, such as ZEB1 and Snail. Under conditions of over-expression of COX-2 and/or MMP2/9, sulforaphane was still able to induce E-cadherin or reduce Snail/ZEB1 expression, suggesting that additional pathways might be involved. Further studies indicated that miR-200c played a role in the regulation of E-cadherin via the ZEB1 repressor but not by the Snail repressor. In conclusion, the EMT and two recognized signaling pathways (COX-2/MMP2,9/ ZEB1, Snail and miR-200c/ZEB1) are all targets for sulforaphane. This study indicated that sulforaphane may possess therapeutic potential in preventing recurrence of human bladder cancer.

Proinflammatory cytokines induced altered expression of cyclooxygenase-2 gene results in unreceptive endometrium in women with idiopathic recurrent spontaneous miscarriage

OBJECTIVE

To investigate the expression pattern of proinflammatory, anti-inflammatory, and angiogenic cytokines and their effect on various mediators of endometrial receptivity in women with idiopathic recurrent spontaneous miscarriage (IRSM).

DESIGN

A prospective study.

SETTING

Tertiary care hospital and reproductive health research unit.

PATIENT(S)

Thirty-six women with IRSM (<35 years) and 30 fertile women as controls matched by age and body mass index undergoing sterilization.

INTERVENTION(S)

Endometrial biopsies in all women corresponding to the window of implantation.

MAIN OUTCOME MEASURE(S)

Assessment of endometrial expression of proinflammatory, anti-inflammatory, and angiogenic cytokines, mediators of matrix turnover and angiogenesis, markers of receptivity.

RESULT(S)

A statistical significantly higher level of proinflammatory cytokines, mediators of matrix turnover and angiogenesis, and a reduced expression of anti-inflammatory and angiogenic cytokines were observed in women with IRSM. Additionally, the markers of endometrial receptivity were poorly expressed in women with IRSM.

CONCLUSION(S)

Aberrant expression of proinflammatory, anti-inflammatory, and angiogenic cytokines during implantation window in women with IRSM is one of the key factors that adversely affect endometrial development, as evidenced by the inadequate expression of various endometrial receptivity markers.

Inflammation-induced protein carbonylation contributes to poor prognosis for cholangiocarcinoma

Carbonylation is an irreversible and irreparable protein modification induced by oxidative stress. Cholangiocarcinoma (CCA) is associated with chronic inflammation caused by liver fluke infection. To investigate the relationship between protein carbonylation and CCA progression, carbonylated proteins were detected by 2D OxyBlot and identified by MALDI-TOF/TOF analyses in pooled CCA tissues in comparison to adjacent nontumor tissues and normal liver tissues. We identified 14 highly carbonylated proteins in CCA tissues. Immunoprecipitation and Western blot analyses of individual samples confirmed significantly greater carbonylation of serotransferrin, heat shock protein 70-kDa protein 1 (HSP70.1), and α1-antitrypsin (A1AT) in tumor tissues compared to normal tissues. The oxidative modification of these proteins was significantly associated with poor prognoses as determined by the Kaplan-Meier method. LC-MALDI-TOF/TOF mass spectrometry identified R50, K327, and P357 as carbonylated sites in serotransferrin, HSP70.1, and A1AT, respectively. Moreover, iron accumulation was significantly higher in CCA tissues with, compared to those without, carbonylated serotransferrin. We conclude that carbonylated serotransferrin-associated iron accumulation may induce oxidative stress via the Fenton reaction, and the carbonylation of HSP70.1 with antioxidative property and A1AT with protease inhibitory capacity may cause them to become dysfunctional, leading to CCA progression.

The liquid Panax ginseng inhibits epidermal growth factor-induced metalloproteinase 9 and cyclooxygenase 2 expressions via inhibition of inhibitor factor kappa-B-alpha and extracellular signal-regulated kinase in NCI-H292 human airway epithelial cells

BACKGROUND

Ginseng (Panax ginseng C.A. Meyer) has been used in Asian countries for the treatment of various diseases. However, the mechanisms of liquid Panax ginseng (LG) on allergic inflammatory response in epidermal growth factor (EGF)-stimulated human airway epithelial cells remain largely unclear.

METHODS

MUC5AC, cyclooxygenase (COX) 2, and matrix metalloproteinase (MMP) 9 expressions were measured using reverse transcription-polymerase chain reaction, Western blotting, and gelatin zymogram analyses in NCI-H292 cells. Extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) protein levels were analyzed by Western blotting.

RESULTS

To gain insight into the antiallergy effects of LG, we examined its influence on epidermal growth factor (EGF)-induced MMP-9 and COX-2 productions in NCI-H292 cells. LG was treated for 1 hour and then followed by EGF treatment for 24 hours into NCI-H292 cells. The decrease of COX-2 production was correlated with the reduced levels of proteins and mRNAs of inducible MMP-9 and MUC5AC. LG blocked upstream signaling of NF-kappa-B activation via inhibition of phosphorylations of inhibitor factor-kappa- B-alpha (I-kappa-B-alpha) and ERK. These results suggest that LG protects NCI-H292 cells from EGF-induced damage by down-regulation of COX-2, MMP-9, and MUC5AC gene expressions by blocking NF-kappa-B and ERK.

CONCLUSION

LG modulates allergic inflammatory response in EGF-stimulated NCI-H292 human airway epithelial cells via inhibition of I-kappa-B-alpha and ERK.

Prostaglandin E2 induces matrix metalloproteinase 9 expression in dendritic cells through two independent signaling pathways leading to activator protein 1 (AP-1) activation

Dendritic Cells (DCs) play an important role in the initiation of the immune response by migrating to regional lymph nodes and presenting antigen processed at the inflammatory site to antigen-specific naïve T cells. Prostaglandin E2 (PGE2) has been reported to play an essential role in DC migration. We reported previously that PGE2 induces matrix metalloproteinase 9 (MMP-9) expression in DCs and that PGE2-induced MMP-9 is required for DC migration in vivo and in vitro. In this study, we investigated the signaling mechanisms involved in PGE2-induced MMP-9 expression in DCs. We show that PGE2-induced MMP-9 expression is mediated primarily through the EP2/EP4 → cAMP → protein kinase A (PKA)/PI3K → ERK signaling pathway, leading to c-Fos expression, and through JNK-mediated activation of c-Jun in a PKA/PI3K/ERK-independent manner. EP2 and EP4 receptor agonists, as well as cAMP analogs, mimic the up-regulation of MMP-9 by PGE2. PKA, PI3K, and ERK inhibitors abolished PGE2- and cAMP-induced c-Fos and MMP-9 up-regulation, and ERK activation was required for the binding of activator protein 1 (AP-1) transcription factor to the MMP-9 promoter. Our results describe a new molecular mechanism for the effect of PGE2 on MMP-9 production in DCs that could lead to future therapeutic approaches using ERK inhibitors to regulate DC migration.

Inhibitory effect of phytoglycoprotein (38 kDa) on expression of matrix metalloproteinase-9 in 12-O-tetradecanoylphorbol-13-acetate-treated HepG2cells

Tumor metastasis is one of the main causes of death for patients with malignant tumors. Matrix metalloproteinase-9 (MMP-9) has been implicated in the invasion and metastasis of various cancer cells. Firstly, glycoprotein isolated from Styrax japonica Siebold et al. Zuccarini (SJSZ) has a molecular weight with 38 kDa and consists of carbohydrate (57.64%) and protein (42.35%). In the composition of SJSZ glycoprotein, carbohydrate mostly consists of glucose (28.17%), galactose (21.85%) and mannose (2.62%) out of 52.64%, respectively. the protein consists of Trp (W, 7.01%), Pro (P, 6.72%), and Ile (I, 5.42%) out of 42.35% as three major amino acids, while total amount of other amino acids is 23.20%. The present study was designed to demonstrate whether or not SJSZ glycoprotein prevents the activity of MMP-9 as a metastasis factor against 12-O-tetradecanoylphorbol-13-acetate (TPA). The study evaluated intracellular ROS and the phosphorylation of mitogen-activated protein kinases (MAPKs: extracellular signal-regulated kinase [ERK], stress-activated protein kinase/c-Jun N-terminal kinase [SAPK/JNK] and the p38 MAPK), the activities of transcriptional factors (nuclear factor [NF]-κB and activator protein [AP]-1), cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), and MMP-9 in TPA-induced HepG2 cells using the Western blotting analysis, EMSA and gelatin zymography. The results showed that SJSZ glycoprotein (50 μg/ml) suppressed the production of intracellular ROS and the phosphorylation of ERK, JNK and p38 MAPK, as well as the activities of transcriptional factors (NF-κB and AP-1), COX-2, iNOS, and MMP-9 in TPA-induced HepG2 cells. Taking the aforementioned results into account together, this present study suggested that SJSZ glycoprotein might be a potent anti-metastatic agent that suppresses MMP-9 enzymatic activity via the NF-κB and AP-1 signaling pathway.

Tan IIA inhibits COX-2-regulated VEGF expression in human colon cancer HCT-116 cells

AIM: To investigate the effect of tanshinone IIA (Tan IIA), an active component of salvia miltiorrhiza, on cell proliferation and cyclooxygenase-2 (COX-2)-regulated vascular endothelial growth factor (VEGF) expression in human colon cancer HCT-116 cells.

METHODS: MTT assay was used to evaluate the effect of Tan IIA on the proliferation of HCT-116 cells. HCT-116 cells were co-transfected transiently with the recombinant plasmid pGL3-Basic-COX-2-promoter and control vector pRL-TK and randomly divided into blank group, control group, and Tan IIA group. Dual luciferase reporter assay was used to observe the activity of COX-2 promoter 48 h after treatment with Tan IIA. HCT-116 cells were transfected with the pIRESI-COX-2 plasmid and divided into three groups as above. The expression of COX-2 mRNA in transfected cells was detected by real-time PCR, and the level of VEGF in culture medium was assayed by ELISA.

RESULTS: Tan IIA had obvious inhibition on the proliferation of HCT-116 cells. The half maximal inhibitory concentrations (IC₅₀) at 24, 48, and 72 h were 40.3 μmol/L ± 5.22 μmol/L, 12.9 μmol/L ± 3.24 μmol/L, and 8.5 μmol/L ± 1.47 μmol/L, respectively, and the maximal no-effect dose at 24 h was 10 μmol/L. At 48 h after transfection with plasmids carrying the COX-2-promoter and COX-2 cDNA, the activity of COX-2 promoter and expression of COX-2 mRNA were obviously up-regulated (both P < 0.01), and the concentration of VEGF was three times higher than that in control cells (P < 0.05). Treatment with 10 μmol/L Tan IIA significantly down-regulated the expression of COX-2 and VEGF in transfected cells (P < 0.05).

CONCLUSION: Tan IIA down-regulates VEGF expression and inhibits cell proliferation possibly by regulating COX-2 promoter activity and mRNA expression in HCT-116 cells.

Markers of bile duct tumors

Biliary tract carcinomas are relatively rare, representing less than 1% of cancers. However, their incidence has increased in Japan and in industrialized countries like the USA. Biliary tract tumors have a poor prognosis and a high mortality rate because they are usually detected late in the course of the disease; therapeutic treatment options are often limited and of minimal utility. Recent studies have shown the importance of serum and molecular markers in the diagnosis and follow up of biliary tract tumors. This review aims to introduce the main features of the most important serum and molecular markers of biliary tree tumors. Some considerable tumor markers are cancer antigen 125, carbohydrate antigen 19-9, carcinoembryonic antigen, chromogranin A, mucin 1, mucin 5, alpha-fetoprotein, claudins and cytokeratins.

Selective inhibition of prostaglandin E2 receptors EP2 and EP4 inhibits invasion of human immortalized endometriotic epithelial and stromal cells through suppression of metalloproteinases

Prostaglandin E2 (PGE2) plays an important role in the pathogenesis of endometriosis. We recently reported that inhibition of COX-2 decreased migration as well as invasion of human endometriotic epithelial and stromal cells. Results of the present study indicates that selective inhibition of PGE2 receptors EP2 and EP4 suppresses expression and/or activity of MMP1, MMP2, MMP3, MMP7 and MMP9 proteins and increases expression of TIMP1, TIMP2, TIMP3, and TIMP4 proteins and thereby decreases migration and invasion of human immortalized endometriotic epithelial and stromal cells into matrigel. The interactions between EP2/EP4 and MMPs are mediated through Src and β-arrestin 1 protein complex involving MT1-MMP and EMMPRIN in human endometriotic cells. These novel findings provide an important molecular and cellular framework for further evaluation of selective inhibition of EP2 and EP4 as potential nonsteroidal therapy for endometriosis in childbearing-age women.

Pathological classification of intrahepatic cholangiocarcinoma based on a new concept

Intrahepatic cholangiocarcinoma (ICC) arises from the lining epithelium and peribiliary glands of the intrahepatic biliary tree and shows variable cholangiocytic differentiation. To date, ICC was largely classified into adenocarcinoma and rare variants. Herein, we propose to subclassify the former, based on recent progress in the study of ICC including the gross classification and hepatic progenitor/stem cells and on the pathological similarities between biliary and pancreatic neoplasms. That is, ICC is classifiable into the conventional (bile duct) type, the bile ductular type, the intraductal neoplasm type and rare variants. The conventional type is further divided into the small duct type (peripheral type) and large bile duct type (perihilar type). The former is a tubular or micropapillary adenocarcinoma while the latter involves the intrahepatic large bile duct. Bile ductular type resembles proliferated bile ductules and shows a replacing growth of the hepatic parenchyma. Hepatic progenitor cell or stem cell phenotypes such as neural cell adhesion molecule expression are frequently expressed in the bile ductular type. Intraductal type includes papillary and tubular neoplasms of the bile duct (IPNBs and ITNBs) and a superficial spreading type. IPNB and ITNB show a spectrum from a preneoplastic borderline lesion to carcinoma and may have pancreatic counterparts. At invasive sites, IPNB is associated with the conventional bile duct ICC and mucinous carcinoma. Biliary mucinous cystic neoplasm with ovarian-like stroma in its wall is different from IPNB, particularly IPNB showing cystic dilatation of the affected ducts. Rare variants of ICC include squamous/adenosquamous cell carcinoma, mucinous/signet ring cell carcinoma, clear cell type, undifferentiated type, neuroendocrine carcinoma and so on. This classification of ICC may open up a new field of research of ICC and contribute to the clinical approach to ICC.

Suppression of integrin alpha3beta1 in breast cancer cells reduces cyclooxygenase-2 gene expression and inhibits tumorigenesis, invasion, and cross-talk to endothelial cells

Integrin receptors for cell adhesion to extracellular matrix have important roles in promoting tumor growth and progression. Integrin alpha3beta1 is highly expressed in breast cancer cells in which it is thought to promote invasion and metastasis; however, its roles in regulating malignant tumor cell behavior remain unclear. In the current study, we used short-hairpin RNA (shRNA) to show that suppression of alpha3beta1 in a human breast cancer cell line, MDA-MB-231, leads to decreased tumorigenicity, reduced invasiveness, and decreased production of factors that stimulate endothelial cell migration. Real-time PCR revealed that suppression of alpha3beta1 caused a dramatic reduction in expression of the cyclooxygenase-2 (COX-2) gene, which is frequently overexpressed in breast cancers and has been exploited as a therapeutic target. Decreased COX-2 was accompanied by reduced prostaglandin E2 (PGE(2)), a major prostanoid produced downstream of COX-2 and an important effector of COX-2 signaling. shRNA-mediated suppression of COX-2 showed that it has a role in tumor cell invasion and cross-talk to endothelial cells. Furthermore, treatment with PGE(2) restored these functions in alpha3beta1-deficient MDA-MB-231 cells. These findings identify a role for alpha3beta1 in regulating two properties of tumor cells that facilitate cancer progression: invasiveness and ability to stimulate endothelial cells. They also reveal a novel role for COX-2 as a downstream effector of alpha3beta1 in tumor cells, thereby identifying alpha3beta1 as a potential therapeutic target to inhibit breast cancer.