Overexpression of ECM1 contributes to migration and invasion in cholangiocarcinoma cell

Extracellular matrix protein 1 (ECM1) is a potential biomarker in B cell acute lymphoblastic leukemia

B cell acute lymphoblastic leukemia (ALL) is characterized by the highly heterogeneity of pathogenic genetic background, and there are still approximately 30-40% of patients without clear molecular markers. To identify the dysregulated genes in B cell ALL, we screened 30 newly diagnosed B cell ALL patients and 10 donors by gene expression profiling chip. We found that ECM1 transcription level was abnormally elevated in newly diagnosed B cell ALL and further verified in another 267 cases compared with donors (median, 124.57% vs. 7.14%, P < 0.001). ROC analysis showed that the area under the curve of ECM1 transcription level at diagnosis was 0.89 (P < 0.001). Patients with BCR::ABL1 and IKZF1 deletion show highest transcription level (210.78%) compared with KMT2A rearrangement (39.48%) and TCF3::PBX1 rearrangement ones (30.02%) (all P < 0.05). Also, the transcription level of ECM1 was highly correlated with the clinical course, as 20 consecutive follow-up cases indicated. The 5-year OS of patients (non-KMT2A and non-TCF3::PBX1 rearrangement) with high ECM1 transcription level was significantly worse than the lower ones (18.7% vs. 72.9%, P < 0.001) and high ECM1 transcription level was an independent risk factor for OS (HR = 5.77 [1.75-19.06], P = 0.004). After considering transplantation, high ECM1 transcription level was not an independent risk factor, although OS was still poor (low vs. high, 71.1% vs. 56.8%, P = 0.038). Our findings suggested that ECM1 may be a potential molecular marker for diagnosis, minimal residual disease (MRD) monitoring, and prognosis prediction of B cell ALL.Trial registration Trial Registration Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTR-OPC-14005546]; http://www.chictr.org.cn .

MUG CCArly: A Novel Autologous 3D Cholangiocarcinoma Model Presents an Increased Angiogenic Potential

Cholangiocarcinoma (CCA) are characterized by their desmoplastic and hypervascularized tumor microenvironment (TME), which is mainly composed of tumor cells and cancer-associated fibroblasts (CAFs). CAFs play a pivotal role in general and CCA tumor progression, angiogenesis, metastasis, and the development of treatment resistance. To our knowledge, no continuous human in vivo-like co-culture model is available for research. Therefore, we aimed to establish a new model system (called MUG CCArly) that mimics the desmoplastic microenvironment typically seen in CCA. Proteomic data comparing the new CCA tumor cell line with our co-culture tumor model (CCTM) indicated a higher gene expression correlation of the CCTM with physiological CCA characteristics. A pro-angiogenic TME that is typically observed in CCA could also be better simulated in the CCTM group. Further analysis of secreted proteins revealed CAFs to be the main source of these angiogenic factors. Our CCTM MUG CCArly represents a new, reproducible, and easy-to-handle 3D CCA model for preclinical studies focusing on CCA-stromal crosstalk, tumor angiogenesis, and invasion, as well as the immunosuppressive microenvironment and the involvement of CAFs in the way that drug resistance develops.

Urinary Eubacterium sp. CAG:581 Promotes Non-Muscle Invasive Bladder Cancer (NMIBC) Development through the ECM1/MMP9 Pathway

BACKGROUND

Increasing evidence points to the urinary microbiota as a possible key susceptibility factor for early-stage bladder cancer (BCa) progression. However, the interpretation of its underlying mechanism is often insufficient, given that various environmental conditions have affected the composition of urinary microbiota. Herein, we sought to rule out confounding factors and clarify how urinary Eubacterium sp. CAG:581 promoted non-muscle invasive bladder cancer (NMIBC) development.

METHODS

Differentially abundant urinary microbiota of 51 NMIBC patients and 47 healthy controls (as Cohort 1) were first determined by metagenomics analysis. Then, we modeled the coculture of NMIBC organoids with candidate urinary Eubacterium sp. CAG:581 in anaerobic conditions and explored differentially expressed genes of these NMIBC tissues by RNA-Seq. Furthermore, we dissected the mechanisms involved into Eubacterium sp. CAG:581 by inducing extracellular matrix protein 1 (ECM1) and matrix metalloproteinase 9 (MMP9) upregulation. Finally, we used multivariate Cox modeling to investigate the clinical relevance of urinary Eubacterium sp. CAG:581 16S ribosomal RNA (16SrRNA) levels to the prognosis of 406 NMIBC patients (as Cohort 2).

RESULTS

Eubacterium sp. CAG:581 infection accelerated the proliferation of NMIBC organoids (p < 0.01); ECM1 and MMP9 were the most upregulated genes induced by the increased colony forming units (CFU) gradient of Eubacterium sp. CAG:581 infection via phosphorylating ERK1/2 in NMIBC organoids of Cohort 1. Excluding the favorable impact of potential contributing factors, the ROC curve of Cohort 2 manifested its 3-year AUC value as 0.79 and the cut-off point of Eubacterium sp. CAG:581 16SrRNA as 10.3 (delta CT value).

CONCLUSION

Our evidence suggests that urinary Eubacterium sp. CAG:581 promoted NMIBC progression through the ECM1/MMP9 pathway, which may serve as the promising noninvasive diagnostic biomarker for NMIBC.

Wentilactone A Reverses the NF-κB/ECM1 Signaling-Induced Cisplatin Resistance through Inhibition of IKK/IκB in Ovarian Cancer Cells

Wentilactone A (WA) is a tetranorditerpenoid isolated from marine algae. We previously found that WA inhibited cancer cell proliferation with little toxicity. In this study, we show that high expression of extracellular matrix protein-1 (ECM1) promotes cancer cell cisplatin resistance, and the secreted ECM1 activates normal fibroblasts (NFs) to transform cells with characteristics of cancer-associated fibroblasts (CAFs). Transcription of the ECM1 gene is regulated largely by NF-κB through EP881C/T-EP266C binding sites. WA supresses the phosphorylation of NF-κB through inhibition of the upstream IKK/IκB phoshorylation to block the expression of ECM1, which reverses the cisplatin-induced activation of NF-κB/ECM1. On the contrary, cisplatin facilitates phosphorylation of NF-κB to enhance the expression of ECM1. These results highlight ECM1 as a potential target for treatment of cisplatin-resistant cancers associated with the ECM1 activated signaling. In addition, WA reverses cisplatin resistance by targeting both tumor cells and the tumor microenvironment through IKK/IκB/NF-κB signaling to reduce the expression of the ECM1 protein.

Extracellular Matrix Protein 1 Regulates Colorectal Cancer Cell Proliferative, Migratory, Invasive and Epithelial-Mesenchymal Transition Activities Through the PI3K/AKT/GSK3β/Snail Signaling Axis

In prior reports, extracellular matrix protein 1 (ECM1) upregulation has been reported in colorectal cancer (CRC) patient tumor tissues, and has been suggested to be related to the metastatic progression of CRC, although the underlying mechanisms have yet to be clarified. In this study, we found that ECM1 was overexpressed in both CRC tissues and cell lines. Upregulation of ECM1 was correlated with tumor size, lymph node status and TNM stage in CRC patients. Knocking down ECM1 suppressed CRC cell growth, migration and invasion, in addition to reducing the expression of Vimentin and increasing E-cadherin expression. The overexpression of ECM1, in contrast, yielded the opposite phenotypic outcomes while also promoting the expression of p-AKT, p-GSK3β, and Snail, which were downregulated when ECM1 was knocked down. Treatment with LY294002 and 740 Y-P reversed the impact upregulation and downregulation of ECM1 on CRC cell metastasis and associated EMT induction. In vivo analyses confirmed that ECM1 overexpression was able to enhance EMT induction and CRC tumor progression. In conclusion, ECM1 influences CRC development and progression in an oncogenic manner, and regulates CRC metastasis and EMT processes via the PI3K/AKT/GSK3β/Snail signaling axis.

Brusatol Inhibits Proliferation and Invasion of Glioblastoma by Down-Regulating the Expression of ECM1

Brusatol (Bru), a Chinese herbal extract, has a variety of anti-tumor effects. However, little is known regarding its role and underlying mechanism in glioblastoma cells. Here, we found that Bru could inhibit the proliferation of glioblastoma cells in vivo and in vitro. Besides, it also had an inhibitory effect on human primary glioblastoma cells. RNA-seq analysis indicated that Bru possibly achieved these effects through inhibiting the expression of extracellular matrix protein 1 (ECM1). Down-regulating the expression of ECM1 via transfecting siRNA could weaken the proliferation and invasion of glioblastoma cells and promote the inhibitory effect of Bru treatment. Lentivirus-mediated overexpression of ECM1 could effectively reverse this weakening effect. Our findings indicated that Bru could inhibit the proliferation and invasion of glioblastoma cells by suppressing the expression of ECM1, and Bru might be a novel effective anticancer drug for glioblastoma cells.

Downregulation of Long Non-coding RNA FALEC Inhibits Gastric Cancer Cell Migration and Invasion Through Impairing ECM1 Expression by Exerting Its Enhancer-Like Function

Long non-coding RNAs (lncRNAs) have been shown to play important roles in many human diseases. However, their functions and mechanisms in tumorigenesis and development remain largely unknown. Here, we demonstrated that focally amplified lncRNA in epithelial cancer (FALEC) was upregulated and significantly correlated with lymph node metastasis, TNM stage in gastric cancer (GC). Further experiments revealed that FALEC knockdown significantly inhibited GC cells migration and invasion in vitro. Mechanistic investigations demonstrated that small interfering RNA-induced silencing of FALEC decreased expression of the nearby gene extracellular matrix protein 1 (ECM1) in cis. Additionally, ECM1 and FALEC expression were positively correlated, and high levels of ECM1 predicted shorter survival time in GC patients. Our results suggest that the downregulation of FALEC significantly inhibited the migration and invasion of GC cells through impairing ECM1 expression by exerting an enhancer-like function. Our work provides valuable information and a novel promising target for developing new therapeutic strategies in GC.

Extracellular matrix protein 1 (ECM1) is associated with carcinogenesis potential of human bladder cancer

Background

Bladder cancer (BCa) is a common urological malignant tumor worldwide, and recurrence and death still remain high. New therapeutic targets are needed to treat patients who are not sensitive to current therapy. Extracellular matrix protein 1 (ECM1) is a key player in multiple epithelial malignancies. However, the knowledge regarding the expression of ECM1 in BCa and the mechanisms by which ECM1 affects BCa tumor progression is unclear.

Materials and methods

ECM1 expression levels in BCa tissues and cells were detected by quantitative real-time PCR (qRT-PCR), immunohistochemistry and Western blot. ECM1 expression was suppressed by shRNAs. Cell Counting Kit-8 (CCK-8), luminescent cell viability assay and 5-ethynyl-2′-deoxyuridine (EdU) assay were used to detect cell proliferation. Flow cytometry and transwell assay were used to evaluate cell apoptosis and invasion, respectively. All statistical analyses were performed by using the GraphPad Prism 7 software package.

Results

In this study, the expression of ECM1 in BCa specimens and cell lines was examined and displayed a significant increase compared with noncancerous counterparts, while ECM1-knockdown affected not only cell proliferation and migration, but also cell invasion ability and apoptosis potential, corresponding to the finding that ECM1 overexpression in BCa patients was associated with a poor prognosis. Additionally, after suppression of ECM1, the expression of glucose transporter 1 (GLUT1), lactate dehydrogenase (LDHA) and hypoxia-inducible factor 1α (HIF-1α), genes involved in Warburg effect regulation, were significantly decreased, and the lactate production was also obviously reduced in ECM1-silenced cells.

Conclusion

Our investigations revealed that the expression of ECM1 was closely associated with tumor cell growth, migration and apoptosis at least in part through regulation of Warburg effect, defining ECM1 as an effective predictor in the carcinogenesis and postoperative recurrence of human BCa.

Targeting the PI3K/AKT/mTOR pathway in biliary tract cancers: A review of current evidences and future perspectives

Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches. The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes. Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy. This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors.

Myoepithelial Cells of Submucosal Glands Can Function as Reserve Stem Cells to Regenerate Airways after Injury

Cells demonstrate plasticity following injury, but the extent of this phenomenon and the cellular mechanisms involved remain underexplored. Using single-cell RNA sequencing (scRNA-seq) and lineage tracing, we uncover that myoepithelial cells (MECs) of the submucosal glands (SMGs) proliferate and migrate to repopulate the airway surface epithelium (SE) in multiple injury models. Specifically, SMG-derived cells display multipotency and contribute to basal and luminal cell types of the SMGs and SE. Ex vivo expanded MECs have the potential to repopulate and differentiate into SE cells when grafted onto denuded airway scaffolds. Significantly, we find that SMG-like cells appear on the SE of both extra- and intra-lobular airways of large animal lungs following severe injury. We find that the transcription factor SOX9 is necessary for MEC plasticity in airway regeneration. Because SMGs are abundant and present deep within airways, they may serve as a reserve cell source for enhancing human airway regeneration.

Extracellular matrix protein 1 promotes cell metastasis and glucose metabolism by inducing integrin β4/FAK/SOX2/HIF-1α signaling pathway in gastric cancer

Extracellular matrix protein 1 (ECM1) is related to strong invasiveness and poor prognosis in major malignancies, but the underlying mechanism remains unknown. Here we aimed to elucidate the function of ECM1 on cell metastasis and glucose metabolism in gastric cancer (GC). The level of ECM1 in sera and tissues of patient with GC were positively correlated with tumor invasion and recurrence. Genetic manipulation of ECM1 expression affected cell metastasis and glucose metabolism in GC cell lines. Enhanced ECM1 expression facilitated gene expression levels associated with epithelial-mesenchymal transition (EMT) and glucose metabolism. Interestingly, our results indicated that ECM1 directly interacted with integrin β4 (ITGB4) and activated ITGB4/focal adhesion kinase (FAK)/glycogen synthase kinase 3β signaling pathway, which further induced the expression of transcription factor SOX2. Aberrant expression of SOX2 altered gene expression of EMT factors and glucose metabolism enzymes. Furthermore, SOX2 enhanced hypoxia-inducible factor α (HIF-1α) promoter activity to regulate glucose metabolism. The micro-positron emission tomography/computed tomography imaging of xenograft model showed that ECM1 substantially increased ¹⁸F-fluorodeoxyglucose uptake in xenograft tumors. Using in vivo mouse tail vein injection experiments, ECM1 was also found to increase in lung surface metastasis. These findings provide evidence that ECM1 regulates GC cell metastasis and glucose metabolism by inducing ITGB4/FAK/SOX2/HIF-1α signal pathway and have important implications for the development of therapeutic target to prevent tumor metastasis and recurrence.

Development of a Sensitive Luciferase-Based Sandwich ELISA System for the Detection of Human Extracellular Matrix 1 Protein

Enzyme-linked immunosorbent assay (ELISA) has been one of the main methods for detecting an antigen in an aqueous sample for more than four decades. Nowadays, one of the biggest concerns for ELISA is still how to improve the sensitivity of the assay, and the luciferase-luciferin reaction system has been noticed as a new detection method with high sensitivity. In this study, a luciferin-luciferase reaction system was used as the detection method for a sandwich ELISA system. It was shown that this new system led to an increase in the detection sensitivity of at least two times when compared with the traditional horseradish peroxidase (HRP) detection method. Lastly, the serum levels of the human extracellular matrix 1 protein of breast cancer patients were determined by the new system, which were overall similar to the HRP chemiluminescent system. Furthermore, this new luciferase reporter can be implemented into other ELISA systems for the purpose of increasing the assay sensitivity.

Extracellular matrix 1 (ECM1) regulates the actin cytoskeletal architecture of aggressive breast cancer cells in part via S100A4 and Rho-family GTPases

ECM1 overexpression is an independent predictor of poor prognosis in primary breast carcinomas, however the mechanisms by which ECM1 affects tumor progression have not been completely elucidated. ECM1 was silenced in the triple-negative breast cancer cell lines Hs578T and MDAMB231 using siRNA and the cells were evaluated for changes in morphology, migration, invasion and adhesion. Actin cytoskeleton alterations were evaluated by fluorescent staining and levels of activated Rho GTPases by pull down assays. ECM1 downregulation led to significantly diminished cell migration (p = 0.0005 for Hs578T and p = 0.02 for MDAMB231) and cell adhesion (p < 0.001 for Hs578T and p = 0.01 for MDAMB231). Cell invasion (matrigel) was reduced only in the Hs578T cells (p < 0.01). Silencing decreased the expression of the prometastatic molecules S100A4 and TGFβR2 in both cell lines and CD44 in Hs578T cells. ECM1-silenced cells also exhibited alterations in cell shape and showed bundles of F-actin across the cell (stress fibers) whereas NT-siRNA treated cells showed peripheral membrane ruffling. Downregulation of ECM1 was also associated with an increased F/G actin ratio, when compared to the cells transfected with NT siRNA (p < 0.001 for Hs578T and p < 0.00035 for MDAMB231) and a concomitant decline of activated Rho A in the Hs578T cells. Re-expression of S100A4 in ECM1-silenced cells rescued the phenotype in the Hs578T cells but not the MDAMB231 cells. We conclude that ECM1 is a key player in the metastatic process and regulates the actin cytoskeletal architecture of aggressive breast cancer cells at least in part via alterations in S100A4 and Rho A.

ECM1 promotes migration and invasion of hepatocellular carcinoma by inducing epithelial-mesenchymal transition

Background

Extracellular matrix protein 1 (ECM1) is a glycoprotein involved in many biologic processes. To determine the expression of ECM1 in hepatocellular carcinoma (HCC), and to study the role of ECM1 in inducing epithelia-mesenchymal transition (EMT) to analyze the effect of ECM1 on the migration and invasion of HCC cells.

Methods

The expression of ECM1 in HCC specimens was examined by immunohistochemistry staining, and the correlations were analyzed between the expression of ECM1 and the clinicopathological data. The ECM1 expression plasmid was transfected into Bel-7402 cells to induce exogenous overexpression of ECM1 protein. The changes of the expression of ECM1, EMT-related protein (E-cadherin, Vimentin), in Bel-7402 cells were detected by Western blot after transfection of ECM1; the wound healing and invasion assay in vitro were used to determine the role of ECM1 gene transfection on the ability of migration and invasive potential of Bel-7402 cells.

Results

Immumohistochemistry staining method displayed the ECM1 expression was positively associated with vascular invasion, TNM stage, and poor prognosis. A significant positive correlation was found between the expressions of ECM1 and Vimentin. After ECM1 overexpression, Western blot exhibited that the expression of E-cadherin was down-regulated and Vimentin expression was up-regulated in Bel-7402 cells; the wound healing and invasion assay showed that the migration and invasion potentials of Bel-7402 cells were significantly enhanced.

Conclusions

ECM1, which displayed a high expression in HCC specimens, was closely associated with clinicopathologic data and may promote migration and invasion of HCC cells by inducing EMT.

Electronic supplementary material

The online version of this article (doi:10.1186/s12957-016-0952-z) contains supplementary material, which is available to authorized users.

Elevated serum CA72-4 levels predict poor prognosis in pancreatic adenocarcinoma after intensity-modulated radiation therapy

Carbohydrate antigen 72-4 (CA72-4) is a human tumor-associated glycoprotein, commonly used as a tumor marker for diagnosing and predicting outcome in gastric and ovarian cancers. However, the relationship between serum CA72-4 levels and prognosis of pancreatic adenocarcinoma has not been fully elucidated. A total of 113 consecutive locally advanced pancreatic adenocarcinoma patients who underwent intensity-modulated radiation therapy (IMRT) with or without chemotherapy were enrolled in this study. Serum CA72-4 levels were analyzed using immunoenzymometric assays. The association between serum CA72-4 levels and prognosis was evaluated. Serum CA72-4 levels was related with lymph node metastasis (P<0.001). The median overall survival time was 14.0 months for patients with serum CA72-4 normal levels and 10.0 months for the elevated levels (P<0.001). Multivariate analysis identified that Serum CA72-4 concentration was a significant prognostic factor (P<0.001). The hazard ratio (HR) of elevated serum CA72-4 levels compared with normal serum CA72-4 levels was 2.34 (95% confidence interval [CI]: 1.46-3.73), after adjusted for gender and age. Based on this finding, Serum CA72-4 is a potential marker to predict lymph node metastasis and prognosis in pancreatic adenocarcinoma.

Production and characterization of domain-specific monoclonal antibodies against human ECM1

Human extracellular matrix protein-1 (hECM1), a secreted glycoprotein, is widely expressed in different tissues and organs. ECM1 has been implicated in multiple biological functions, which are potentially mediated by the interaction of different ECM1 domains with its ligands. However, the exact biological functions of ECM1 have not been elucidated yet, and the functional study of ECM1 has been partially hampered by the lack of sensitive and specific antibodies, especially those targeting different ECM1 domains. In this study, six strains of monoclonal antibody (MAb) against hECM1 were generated using purified, prokaryotically-expressed hECM1 as an immunogen. The MAbs were shown to be highly sensitive and specific, and suitable for western blot, immunoprecipitation assays and immunohistochemistry. Furthermore, the particular ECM1 domains recognized by different MAbs were identified. Lastly, the MAbs were found to have neutralizing activities, inhibiting the proliferation, migration and metastasis of MDA-MB-231 cells. In conclusion, the domain-specific anti-ECM1 MAbs produced in this study should provide a useful tool for investigating ECM1's biological functions, and cellular pathways in which it is involved.

ECM1 regulates tumor metastasis and CSC-like property through stabilization of β-catenin

Extracellular Matrix Protein 1 (ECM1) is a marker for tumorigenesis and is correlated with invasiveness and poor prognosis in various types of cancer. However, the functional role of ECM1 in cancer metastasis is unclear. Here, we detected high ECM1 level in breast cancer patient sera that was associated with recurrence of tumor. The modulation of ECM1 expression affected not only cell migration and invasion, but also sphere-forming ability and drug resistance in breast cancer cell lines. In addition, ECM1 regulated the gene expression associated with the epithelial to mesenchymal transition (EMT) progression and cancer stem cell (CSC) maintenance. Interestingly, ECM1 increased β-catenin expression at the post-translational level through induction of MUC1, which was physically associated with β-catenin. Indeed, the association between β-catenin and the MUC1 cytoplasmic tail was increased by ECM1. Furthermore, forced expression of β-catenin altered the gene expression that potentiated EMT progression and CSC phenotype maintenance in the cells. These data provide evidence that ECM1 has an important role in cancer metastasis through β-catenin stabilization.

Extracellular matrix protein 1 regulates cell proliferation and trastuzumab resistance through activation of epidermal growth factor signaling

INTRODUCTION

Extracellular matrix protein 1 (ECM1) is a secreted glycoprotein with putative functions in cell proliferation, angiogenesis and differentiation. Expression of ECM1 in several types of carcinoma suggests that it may promote tumor development. In this study, we investigated the role of ECM1 in oncogenic cell signaling in breast cancer, and potential mechanisms for its effects.

METHODS

In order to find out the functional role of ECM1, we used the recombinant human ECM1 and viral transduction systems which stably regulated the expression level of ECM1. We examined the effect of ECM1 on cell proliferation and cell signaling in vitro and in vivo. Moreover, tissues and sera of patients with breast cancer were used to confirm the effect of ECM1.

RESULTS

ECM1 protein was increased in trastuzumab-resistant (TR) cells, in association with trastuzumab resistance and cell proliferation. Through physical interaction with epidermal growth factor receptor (EGFR), ECM1 potentiated the phosphorylation of EGFR and extracellular signal-regulated kinase upon EGF treatment. Moreover, ECM1-induced galectin-3 cleavage through upregulation of matrix metalloproteinase 9 not only improved mucin 1 expression, but also increased EGFR and human epidermal growth factor receptor 3 protein stability as a secondary signaling.

CONCLUSIONS

ECM1 has important roles in both cancer development and trastuzumab resistance in breast cancer through activation of EGFR signaling.

ECM1 promotes the Warburg effect through EGF-mediated activation of PKM2

The Warburg effect is an oncogenic metabolic switch that allows cancer cells to take up more glucose than normal cells and favors anaerobic glycolysis. Extracellular matrix protein 1 (ECM1) is a secreted glycoprotein that is overexpressed in various types of carcinoma. Using two-dimensional digest-liquid chromatography-mass spectrometry (LC-MS)/MS, we showed that the expression of proteins associated with the Warburg effect was upregulated in trastuzumab-resistant BT-474 cells that overexpressed ECM1 compared to control cells. We further demonstrated that ECM1 induced the expression of genes that promote the Warburg effect, such as glucose transporter 1 (GLUT1), lactate dehydrogenase A (LDHA), and hypoxia-inducible factor 1 α (HIF-1α). The phosphorylation status of pyruvate kinase M2 (PKM-2) at Ser37, which is responsible for the expression of genes that promote the Warburg effect, was affected by the modulation of ECM1 expression. Moreover, EGF-dependent ERK activation that was regulated by ECM1 induced not only PKM2 phosphorylation but also gene expression of GLUT1 and LDHA. These findings provide evidence that ECM1 plays an important role in promoting the Warburg effect mediated by PKM2.

Large-scale proteomics differentiates cholesteatoma from surrounding tissues and identifies novel proteins related to the pathogenesis

Cholesteatoma is the growth of keratinizing squamous epithelium in the middle ear. It is associated with severe complications and has a poorly understood etiopathogenesis. Here, we present the results from extensive bioinformatics analyses of the first large-scale proteomic investigation of cholesteatoma. The purpose of this study was to take an unbiased approach to identifying alterations in protein expression and in biological processes, in order to explain the characteristic phenotype of this skin-derived tumor. Five different human tissue types (cholesteatoma, neck of cholesteatoma, tympanic membrane, external auditory canal skin, and middle ear mucosa) were analyzed. More than 2,400 unique proteins were identified using nanoLC-MS/MS based proteomics (data deposited to the ProteomeXchange), and 295 proteins were found to be differentially regulated in cholesteatoma. Validation analyses were performed by SRM mass spectrometry. Proteins found to be up- or down-regulated in cholesteatoma were analyzed using Ingenuity Pathway Analysis and clustered into functional groups, for which activation state and associations to disease processes were predicted. Cholesteatoma contained high levels of pro-inflammatory S100 proteins, such as S100A7A and S100A7. Several proteases, such as ELANE, were up-regulated, whereas extracellular matrix proteins, such as COL18A1 and NID2, were under-represented. This may lead to alterations in integrity and differentiation of the tissue (as suggested by the up-regulation of KRT4 in the cholesteatoma). The presented data on the differential protein composition in cholesteatoma corroborate previous studies, highlight novel protein functionalities involved in the pathogenesis, and identify new areas for targeted research that hold therapeutic potential for the disease.

In vitro neuraotropic growth of cholangiocarcinoma: an experimental study

Objective

Perineural invasion of cholangiocarcinoma happens in the early stage of the disease but is often not recognized until its later stages. Research about the behaviour and mechanism of perineural invasion by cholangiocarcinoma is urgently needed for a useful new model. The aim of this work is to establish a novel model to address the problem.

Design

Neural cells and cholangiocarcinoma cells were co-cultured to mimic the neurotropic invasion of cholangiocarcinoma.

Setting

Human embryonic stem cells were induced to form neural cells by glial cell-derived neurotropic factor and retinoic acid; neural cells and cholangiocarcinoma cells were co-cultured in Transwell chamber.

Participants

Human embryonic stem cells and cholangiocarcinoma cells were applied.

Main outcome measures

Paired t-test was used to compare the counts of penetrating cholangiocarcinoma cells in co-culture and control group.

Results

Formation of neurospheres and neural-like cells were observed following induction at 24 and 48 h, respectively; synapses were viewed to protrude from neural-like cell bodies after incubation for 96 h. Forty-eight hours after incubation, immunocytochemical staining of the cells showed that synaptophysin and glial fibrillary acidic protein were expressed in the neuron-like cells and gliocytes-like cells, respectively. The cholangiocarcinoma cells that had penetrated through the Matrigel/polyethylene terephthalate membrane from the upper chamber to the lower chamber of the Transwell in the co-culture group were significantly more numerous than those in the control group (68 ± 8.3/field versus 46 ± 5.7/field, P < 0.05).

Conclusion

The novel model is a valuable tool to study the perineural invasion of cholangiocarcinoma.

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.

Human Melanoma cells over-express extracellular matrix 1 (ECM1) which is regulated by TFAP2C

Extracellular matrix 1 (ECM1) is over-expressed in multiple epithelial malignancies. However, knowledge regarding the expression of ECM1 in melanomas and the mechanisms of ECM1 regulation is limited. In this study, we found that ECM1 is over-expressed in several melanoma cell lines, when compared to primary melanocytes, and furthermore, that ECM1 expression paralleled that of TFAP2C levels in multiple cell lines. Knockdown of TFAP2C in the A375 cell line with siRNA led to a reduction in ECM1 expression, and upregulation of TFAP2C with adenoviral vectors in the WM793 cell line resulted in ECM1 upregulation. Utilizing 5’ RACE to identify transcription start sites (TSS) and luciferase reporter assays in the ECM1-overexpressing A375 cell line, we identified the minimal promoter region of human ECM1 and demonstrate that an approximately 100bp fragment upstream of the TSS containing a TATA box and binding sites for AP1, SP1 and Ets is sufficient for promoter activity. Chromatin immunoprecipitation and direct sequencing (ChIP-seq) for TFAP2C in the A375 cell line identified an AP2 regulatory region in the promoter of the ECM1 gene. Gelshift assays further confirmed binding of TFAP2C to this site. ECM1 knockdown reduces melanoma cell attachment and is consistent with findings that ECM1 overexpression has been associated with a poor prognosis. Our investigations show an as yet unrecognized role for TFAP2C in melanoma via its regulation of ECM1.