Amine oxidase, copper containing 3 exerts anti­mesenchymal transformation and enhances CD4+ T­cell recruitment to prolong survival in lung cancer.

Lung cancer remains notorious for its poor prognosis. Despite the advent of tyrosine kinase inhibitors and immune checkpoint inhibitors, the probability of curing the disease in lung cancer patients remains low. Novel mechanisms and treatment strategies are needed to provide hope to patients. Advanced strategies of next generation sequencing (NGS) and bioinformatics were used to analyze normal and lung cancer tissues from lung cancer patients. Amine oxidases have been linked to leukocyte migration and tumorigenesis. However, the roles of amine oxidases in lung cancer are not well­understood. Our results indicated that amine oxidase, copper containing 3 (AOC3) was significantly decreased in the tumor tissue compared with the normal tissue, at both the mRNA and protein level, in the included lung cancer patients and public databases. Lower expression of AOC3 conferred a poorer survival probability across the different cohorts. Epigenetic silencing of AOC3 via miR­3691­5p caused tumor promotion and progression by increasing migration and epithelial­mesenchymal transition (EMT). Furthermore, knockdown of AOC3 caused less CD4+ T­cell attachment onto lung cancer cells and reduced transendothelial migration in vitro, as well as reducing CD4+ T­cell trafficking to the lung in vivo. In conclusion, the present study revealed that downregulation of AOC3 mediated lung cancer promotion and progression, as well as decrease of immune cell recruitment. This novel finding could expand our understanding of the dysregulation of the tumor immune microenvironment and could help to develop a novel strategy for the treatment of lung cancer.

The Downregulation of LSAMP Expression Promotes Lung Cancer Progression and Is Associated with Poor Survival Prognosis.

Lung cancer has been a leading cause of cancer-related death for decades and therapeutic strategies for non-driver mutation lung cancer are still lacking. A novel approach for this type of lung cancer is an emergent requirement. Here we find that loss of LSAMP (Limbic System Associated Membrane Protein), compared to other IgLON family of proteins NTM (Neurotrimin) and OPCML (OPioid-binding Cell adhesion MoLecule), exhibits the strongest prognostic and therapeutic significance in predicting lung adenocarcinoma (LUAD) progression. Lower expression of LSAMP and NTM, but not OPCML, were found in tumor parts compared with normal parts in six LUAD patients, and this was validated by public datasets, Oncomine® and TCGA. The lower expression of LSAMP, but not NTM, was correlated to shorter overall survival. Two epigenetic regulations, including hypermethylation and miR-143-3p upregulation but not copy number variation, were associated with downregulation of LSAMP in LUAD patients. Pathway network analysis showed that NEGR1 (Neuronal Growth Regulator 1) was involved in the regulatory loop of LSAMP. The biologic functions by LSMAP knockdown in lung cancer cells revealed LSMAP was linked to cancer cell migration via epithelial-mesenchymal transition (EMT) but not proliferation nor stemness of LUAD. Our result showed for the first time that LSAMP acts as a potential tumor suppressor in regulating lung cancer. A further deep investigation into the role of LSAMP in lung cancer tumorigenesis would provide therapeutic hope for such affected patients.

Loss of miR-145-5p Causes Ceruloplasmin Interference with PHD-Iron Axis and HIF-2α Stabilization in Lung Adenocarcinoma-Mediated Angiogenesis.

For decades, lung cancer has been the leading cause of cancer-related death worldwide. Hypoxia-inducible factors (HIFs) play critical roles in mediating lung cancer development and metastasis. The present study aims to clarify how HIF's over-activation affects lung cancer angiogenesis not only in a normoxic condition, but also a hypoxic niche. Our study shows that human lung cancer exhibits elevated levels of ceruloplasmin (CP), which has a negative impact on the prognosis of patients. CP affects the cellular Fe2+ level, which inactivates prolyl hydroxylase (PHD) 1 and 2, resulting in HIF-2α enhancement. Increased HIF-2α leads to vascular endothelial growth factor-A (VEGF-A) secretion and angiogenesis. The expression of CP is under the epigenetic control of miR-145-5p. Restoration of miR-145-5p by miRNA mimics transfection decreases CP expression, increases Fe2+ and PHD1/2 levels and HIF hydroxylation while reduced HIF-2α levels resulting in the inhibition of tumor angiogenesis. In contrast, inhibition of miR-145-5p by miRNA inhibitors increases the expression of CP and VEGF-A in lung cancer cells. Significantly, miR-145-5p expression is lost in the tumor samples of lung cancer patients, and low miR-145-5p expression is strongly correlated with a shorter overall survival time. In conclusion, the current study reveals the clinical importance and prognostic value of miR-145-5p and CP. It identifies a unique mechanism of HIF-2α over-activation, which is mediated by iron imbalance of the iron-PHD coupling that modulates tumor angiogenesis.

Upregulation of Thr/Tyr kinase Increases the Cancer Progression by Neurotensin and Dihydropyrimidinase-Like 3 in Lung Cancer.

Lung cancer is one of the leading causes of cancer-related death globally, thus elucidation of its molecular pathology is highly highlighted. Aberrant alterations of the spindle assembly checkpoint (SAC) are implicated in the development of cancer due to abnormal cell division. TTK (Thr/Tyr kinase), a dual serine/threonine kinase, is considered to act as a cancer promoter by controlling SAC. However, the mechanistic details of how TTK-mediated signaling network supports cancer development is still a mystery. Here, we found that TTK was upregulated in the tumor tissue of patients with lung cancer, and enhanced tumor growth and metastasis in vitro and in vivo. Mechanistically, TTK exerted a significant enhancement in cancer growth by neurotensin (NTS) upregulation, and subsequently increased the expression of cyclin A and cdk2, which was resulting in the increase of DNA synthesis. In contrast, TTK increased cell migration and epithelial-to-mesenchymal transition (EMT) by enhancing the expression of dihydropyrimidinase-like 3 (DPYSL3) followed by the increase of snail-regulated EMT, thus reinforce metastatic potential and ultimately tumor metastasis. TTK and DPYSL3 upregulation was positively correlated with a poor clinical outcome in patients with lung cancer. Together, our findings revealed a novel mechanism underlying the oncogenic potential effect of TTK and clarified its downstream factors NTS and DPYSL3 might represent a novel, promising candidate oncogenes with potential therapeutic vulnerabilities in lung cancer.

Systematic Analysis of Transcriptomic Profile of the Effects of Low Dose Atropine Treatment on Scleral Fibroblasts using Next-Generation Sequencing and Bioinformatics.

This study has two novel findings: it is not only the first to deduct potential genes involved in scleral growth repression upon atropine instillation from a prevention point of view, but also the first to demonstrate that only slight changes in scleral gene expression were found after atropine treatment as side effects and safety reasons of the eye drops are of concern. The sclera determines the final ocular shape and size, constituting of scleral fibroblasts as the principal cell type and the major regulator of extracellular matrix. The aim of our study was to identify differentially expressed genes and microRNA regulations in atropine-treated scleral fibroblasts that are potentially involved in preventing the onset of excessive ocular growth using next-generation sequencing and bioinformatics approaches. Differentially expressed genes were functionally enriched in anti-remodeling effects, comprising of structural changes of extracellular matrix and metabolic pathways involving cell differentiation. Significant canonical pathways were correlated to inhibition of melatonin degradation, which was compatible with our clinical practice as atropine eye drops are instilled at night. Validation of the dysregulated genes with previous eye growth-related arrays and through microRNA-mRNA interaction predictions revealed the association of hsa-miR-2682-5p-KCNJ5 and hsa-miR-2682-5p-PRLR with scleral anti-remodeling and circadian rhythmicity. Our findings present new insights into understanding the anti-myopic effects of atropine, which may assist in prevention of myopia development.

Deduction of Novel Genes Potentially Involved in the Effects of Very Low Dose Atropine (0.003%) Treatment on Corneal Epithelial Cells Using Next-Generation Sequencing and Bioinformatics Approaches.

Background and Objectives: Atropine is a nonselective muscarinic antagonist which has been used to prevent worsening of myopia in children. Different concentrations of atropine were used for myopia, ranging from 0.01% to 1.0%. However, there are still potential toxicity of different doses of atropine to the cornea. Here, we present a study of investigating novel genes potentially involved in the effects of very low dose atropine treatment (0.003%) on corneal epithelial cells using next-generation sequencing (NGS) and bioinformatics approaches. Materials and Methods: Human corneal epithelial cells were treated with 0.003% atropine, cultured until confluence, and RNA extracted for differential expression profiling of mRNA and microRNA (miRNA) between control and atropine-treated corneal epithelial cells. The functional enrichment analysis for differentially expressed genes was performed using two bioinformatics databases, including Database for Annotation, Visualization and Integrated Discovery (DAVID) and Ingenuity® Pathway Analysis (IPA). In addition, potential miRNA-mRNA interactions involved in atropine-treated corneal epithelial cells were predicted and validated using different miRNA target prediction databases. Results: Our results showed 0.003% atropine might suppress the apoptosis of corneal epithelial cells, potentially through Ras and protein kinase A signaling pathways. We also validated the possible miRNA regulations by using TargetScan and miRDB databases. Hsa-miR-651-3p-EPHA7, hsa-miR-3148-TMEM108 and hsa-miR-874-5p-TBX6 were validated as possible miRNA regulations involved in corneal epithelial cells treated with 0.003% atropine. Conclusions: These findings may contribute novel insights into therapeutic strategies for treating cornea with 0.003% atropine.

Next-generation sequencing predicts interaction network between miRNA and target genes in lipoteichoic acid-stimulated human neutrophils.

Toll­like receptors (TLRs), which are a class of pattern­recognition receptors, can sense specific molecules of pathogens and then activate immune cells, such as neutrophils. The regulation of TLR signaling in immune cells has been investigated by various studies. However, the interaction of TLR signaling­activated microRNAs (miRNAs) and genes has not been well investigated in a specific type of immune cells. In the present study, neutrophils were isolated from peripheral blood of a healthy donor, and then treated for 16 h with Staphylococcus aureus lipoteichoic acid (LTA), which is an agonist of TLR2. The miRNA and mRNA expression profiles were analyzed via next­generation sequencing and bioinformatics approaches. A total of 290 differentially expressed genes between LTA­treated and vehicle­treated neutrophils were identified. Gene ontology analysis revealed that various biological processes and pathways, including inflammatory responses, defense response, positive regulation of cell migration, motility, and locomotion, and cell surface receptor signaling pathway, were significantly enriched. In addition, 38 differentially expressed miRNAs were identified and predicted to be involved in regulating signal transduction and cell communication. The interaction of 4 miRNAs (hsa­miR­34a­5p, hsa­miR­34c­5p, hsa­miR­708­5p, and hsa­miR­1271­5p) and 5 genes (MET, CACNB3, TNS3, TTYH3, and HBEGF) was proposed to participate in the LTA­induced signaling network. The present findings may provide novel information for understanding the detailed expression profiles and potential networks between miRNAs and their target genes in LTA­stimulated healthy neutrophils.

Systematic analysis of transcriptomic profiles of COPD airway epithelium using next-generation sequencing and bioinformatics.

Introduction: COPD is a chronic inflammatory disease of lung. The inflammatory response in COPD is associated with neutrophils, macrophages, T lymphocytes, and bronchial epithelial cells, and occurs mainly in the small airway, leading to irreversible airflow limitation. Methods: In order to investigate the microRNA-mRNA interaction in the microenvironment of the COPD airway, we used next-generation sequencing and bioinformatics in this study. Results: We identified four genes with microRNA-mRNA interactions involved in COPD small-airway bronchial epithelial cells: NT5E, SDK1, TNS1, and PCDH7. Furthermore, miR6511a-5p-NT5E interaction was found to be involved in small-airway bronchial epithelial cells, large-airway bronchial epithelial cells, and alveolar macrophages. Conclusion: Our results showed that miR6511a-5p-NT5E interaction plays an important role in COPD, which might be associated with cell-cell contact, activation of leukocytes, activation of T lymphocytes, and cellular homeostasis. These findings provide new information for further investigations of the COPD microenvironment, and may help to develop new diagnostic or therapeutic strategies targeting the bronchial epithelium for COPD.

Interaction between Tumor-Associated Dendritic Cells and Colon Cancer Cells Contributes to Tumor Progression via CXCL1.

Crosstalk of a tumor with its microenvironment is a critical factor contributing to cancer development. This study investigates the soluble factors released by tumor-associated dendritic cells (TADCs) responsible for increasing cancer stem cell (CSC) properties, cell mobility, and epithelial-to-mesenchymal transition (EMT). Dendritic cells (DCs) of colon cancer patients were collected for phenotype and CXCL1 expression by flow cytometry and Luminex assays. The transcriptome of CXCL1-treated cancer cells was established by next generation sequencing. Inflammatory chemokine CXCL1, present in large amounts in DCs isolated from colon cancer patients, and SW620-conditioned TADCs, enhance CSC characteristics in cancer, supported by enhanced anchorage-independent growth, CD133 expression and aldehyde dehydrogenase activity. Additionally, CXCL1 increases the metastatic ability of a cancer by enhancing cell migration, matrix metalloproteinase-7 expression and EMT. The enhanced CXCL1 expression in DCs is also noted in mice transplanted with colon cancer cells. Transcriptome analysis of CXCL1-treated SW620 cells indicates that CXCL1 increases potential oncogene expression in colon cancer, including PTHLH, TYRP1, FOXO1, TCF4 and ZNF880. Concurrently, CXCL1 displays a specific microRNA (miR) upregulated by the prototypical colon cancer onco-miR miR-105. Analysis of publicly available data reveals CXCL1-driven oncogenes and miR-105 have a negative prognostic impact on the outcome of colon cancer. This study indicates a new mechanism by which the colon cancer milieu exploits DC plasticity to support cancer progression.

Possible mechanisms mediating apoptosis of bronchial epithelial cells in chronic obstructive pulmonary disease - A next-generation sequencing approach.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease characterized by persistent airflow limitation. Apoptosis of pulmonary structural cells contributes to pulmonary destruction and dysfunction. This study aimed to explore the possible mechanisms underlying decreased cell proliferation and increased apoptosis of bronchial epithelial cells of COPD. MATERIALS AND METHODS: The expression profiles of mRNAs and microRNAs in bronchial epithelial cells from a COPD patient and a normal subject were identified using next-generation sequencing (NGS) and analyzed using bioinformatic tools. RESULTS: We identified 233 significantly upregulated and 204 significantly downregulated genes in COPD bronchial epithelial cells. The PI3K-Akt pathway was one of the most important dysregulated pathways in bronchial epithelial cells. We further identified that 3 genes involved in the PI3K-Akt signaling pathway, including IL6, F2R, and FGFR3, might be associated with inhibition of cell proliferation in bronchial epithelial cells, while 5 genes involved in the PI3K-Akt signaling pathway, including TLR4, IL6, F2R, FGFR3, and FGFR1, might be associated with apoptosis of bronchial epithelial cells. FGFR1 was also a predicted target for some up-regulated miRNAs in COPD bronchial epithelial cells, including hsa-miR-195-5p, hsa-miR-424-5p, and hsa-miR-6724-5p. CONCLUSION: Our findings suggest PI3K-Akt signaling pathway plays an important role in COPD. We observed altered expression of apoptosis and cell proliferation-related genes that might contribute to the pathogenesis of COPD.

Hypoxic Lung-Cancer-Derived Extracellular Vesicle MicroRNA-103a Increases the Oncogenic Effects of Macrophages by Targeting PTEN.

Hypoxia, the most commonly observed characteristic in cancers, is implicated in the establishment of an immunosuppressive niche. Recent studies have indicated that extracellular vesicle (EV)-mediated cancer-stroma interactions are considered to play a critical role in the regulation of various cellular biological functions, with phenotypic consequences in recipient cells. However, the mechanisms underlying the relationship between EVs and hypoxia during cancer progression remain largely unknown. In this study, we found that EVs derived from hypoxic lung cancers increased M2-type polarization by miR-103a transfer. Decreased PTEN levels caused by hypoxic cancer-cell-derived EV miR-103a increased activation of AKT and STAT3 as well as expression of several immunosuppressive and pro-angiogeneic factors. In contrast, inhibition of miR-103a by an miRNA inhibitor effectively decreased hypoxic cancer-mediated M2-type polarization, improving the cytokine prolife of tumor infiltration macrophages. Macrophages received cancer-cell-derived EV miR-103a feedback to further enhance cancer progression and tumor angiogenesis. Finally, circulating EV miR-103a levels were higher in patients with lung cancer and closely associated with the M2 polarization. In conclusion, our results delineate a novel mechanism by which lung cancer cells induce immunosuppressive and pro-tumoral macrophages through EVs and inspire further research into the clinical application of EV inhibition or PTEN restoration for immunotherapy.

Investigation of the role of tumor necrosis factor-like weak inducer of apoptosis in non-small cell lung cancer.

Several of the soluble inflammatory molecules such as cytokines and chemokines are involved in the regulation of cancer behaviors. Tumor necrosis factor (TNF)­like weak inducer of apoptosis (TWEAK) is a member of the TNF superfamily and is a ligand of fibroblast growth factor inducible 14 (Fn14). TWEAK/Fn14 signaling pathways promote tumor progression in several types of human cancer. In the present study, we investigated the role of TWEAK through bioinformatic assay, in vitro experiments, and serum levels in patients with non­small cell lung cancer (NSCLC). Our results indicated that TWEAK expression in normal tissues was higher than that in lung cancer tissues. In contrast, relatively higher Fn14 expression was detected in lung cancer tissues compared to normal tissues. Recombinant TWEAK treatment did not enhance and inhibit the proliferation and migration of human NSCLC cell lines including A549, H1299, CL1­0 and CL1­5. In addition, the serum concentration of TWEAK in normal controls was significantly higher than that in NSCLC patients. However, the TWEAK levels did not show significant difference in regards to TNM stage, cell type and metastasis status in the sera of NSCLC patients. In summary, the present study suggests that a low serum level of TWEAK may be a feature of NSCLC, and the role of TWEAK­mediated pathways warrant further investigation.

Secreted protein acidic and rich in cysteine (SPARC) induces cell migration and epithelial mesenchymal transition through WNK1/snail in non-small cell lung cancer.

The extracellular matrix is a component of physiological microenvironment and a regulator of cellular processes such as migration and proliferation. Secreted Protein Acidic and Rich in Cysteine (SPARC/osteonectin) is an extracellular matrix-associated glycoprotein involved in the regulation of cell proliferation and cell migration in several types of cancers. However, the role of SPARC in lung cancer is paradoxical and details of the regulatory mechanism are not well-known. In this study, we investigated novel SPARC-mediated signaling pathways. Treatment of SPARC increased cell proliferation, migration, and mesenchymal phenotype in two non-small cell lung cancer cell lines, CL1-5 and H1299. We found that these phenotypes were not regulated by focal adhesion kinase and Src kinase, but were mediated by with no lysine (K) kinase 1 (WNK1). Suppression of WNK1 expression decreased the expression of SPARC-induced N-cadherin and smooth muscle actin. Moreover, Snail, an important transcription factor for regulating epithelial-mesenchymal transition, is also involved in SPARC/WNK1 pathway. In a murine tumor model, SPARC treatment significantly induced phosphorylation of Akt and WNK1 in lung tumor nodules when compared to control mice. In conclusion, these data suggest that WNK1 is a novel molecule in SPARC-mediated mesenchymal signaling pathway in non-small cell lung cancer.

Laricitrin ameliorates lung cancer-mediated dendritic cell suppression by inhibiting signal transducer and activator of transcription 3.

Natural polyphenolic compounds of grapes and their seeds are thought to be therapeutic adjuvants in a variety of diseases, including cancer prevention. This study was carried out to investigate the effect of grape phenolic compounds on the regulation of cancer-mediated immune suppression. Laricitrin exhibits the greatest potential to ameliorate the suppressive effects of lung cancer on dendritic cells' (DCs') differentiation, maturation and function. Human lung cancer A549 and CL1-5 cells change the phenotype of DCs that express to high levels of IL-10 and prime T cells towards an immune suppression type-2 response (Th2). Laricitrin treatment stimulated DC differentiation and maturation in the condition media of cancer cells, a finding supported by monocyte marker CD14's disappearance and DC marker CD1a's upregulation. Laricitrin decreases expression of IL-10 in cancer-conditioned DCs, and subsequently switches CD4+ T cell response from Th2 to Th1 in vitro and in vivo. Reversal of laricitrin on lung cancer-induced DCs' paralysis was via inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3). Laricitrin also potentiated the anticancer activity of cisplatin in mouse models. Thus, laricitrin could be an efficacious immunoadjuvant and have a synergistic effect when combined with chemotherapy.

Lung cancer-derived galectin-1 contributes to cancer associated fibroblast-mediated cancer progression and immune suppression through TDO2/kynurenine axis.

Communication between cancer cells and their microenvironment plays an important role in cancer development, but the precise mechanisms by which cancer-associated fibroblasts (CAF) impact anti-cancer immunity and cancer progression in lung cancer are poorly understood. Here, we report that lung fibroblasts when activated by lung cancer cells produce tryptophan metabolite kynurenine (Kyn) that inhibits dendritic cells' differentiation and induces cancer growth as well as migration. We identified TDO2 (tryptophan 2,3-dioxygenase) as the main enzyme expressed in fibroblasts capable of tryptophan metabolism. Mechanistically, condition medium of CAF or exogenous kynurenine stimulated AKT, with no lysine 1 (WNK1) and cAMP response element-bindingprotein (CREB) phosphorylation in lung cancer cells. Inhibition of the AKT/CREB pathway prevents cancer proliferation, while inhibition of the AKT/ WNK1 reverted epithelial-to-mesenchymal transition and cancer migration induced by kynurenine. Moreover, we also demonstrate that lung cancer-derived galectin-1 contributes to the upregulation of TDO2 in CAF through an AKT-dependent pathway. Immunohistochemical analysis of lung cancer surgical specimens revealed increased TDO2 expression in the fibroblasts adjacent to the cancer. Furthermore, in vivo studies showed that administration of TDO2 inhibitor significantly improves DCs function and T cell response, and decreases tumor metastasis in mice. Taken together, our data identify the feedback loop, consisting of cancer-derived galectin-1 and CAF-producing kynurenine, that sustains lung cancer progression. These findings suggest that targeting this pathway may be a promising therapeutic strategy.

Benzyl butyl phthalate increases the chemoresistance to doxorubicin/cyclophosphamide by increasing breast cancer-associated dendritic cell-derived CXCL1/GROα and S100A8/A9.

Phthalates are used as plasticizers in the manufacture of flexible vinyl, which is used in food contact applications. Phthalates have been demonstrated to have an adverse impact on human health, particularly in terms of cancer development. In the present study, we showed for the first time that benzyl butyl phthalate (BBP) potentiates the effect of tumor­associated dendritic cells (TADCs) on the chemoresistance of breast cancer. Specific knockdown analysis revealed that S100A9 is the major factor responsible for the chemoresistance of doxorubicin/cyclophosphamide induced by BBP-stimulated TADCs in breast cancer. BBP exposure also increased tumor infiltrating myeloid-derived suppressor cell (MDSC) secretion of S100A8/A9, thereby exacerbating the resistance of breast cancer to doxorubicin with cyclophosphamide. In addition, BBP also stimulated the production of CXCL1/GROα by TADCs, which increased the angiogenesis of breast cancer in a mouse model. Inhibition of CXCL1/GROα by a neutralizing antibody, decreased the BBP-induced angiogenesis induced by BBP after chemotherapy in the mouse model. These results, for the first time, provide evidence that BBP influences the efficacy of chemotherapy by remodeling the tumor microenvironment of breast cancer.

Epigenetic inactivation of transforming growth factor-ß1 target gene HEYL, a novel tumor suppressor, is involved in the P53-induced apoptotic pathway in hepatocellular carcinoma.

AIM: Hairy/enhancer-of-split related with YRPW motif-like (HEYL) protein was first identified as a transcriptional repressor. It is a downstream gene of the Notch and transforming growth factor-ß pathways. Little is known about its role in the pathogenesis of hepatocellular carcinoma (HCC). METHODS: Eighty surgically resected paired HCC and adjacent non-cancerous tissues were analyzed for HEYL expression by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). HCC cells were transfected with pHEYL-EGFP vector to overexpress the HEYL gene or infected with specific shHEYL lentiviral vector to silence HEYL gene expression. HEYL expressional analysis and functional characterization were assessed by 3-(4 5-dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide assays, flow cytometry, RT-qPCR, western blotting and methylation-specific PCR. RESULTS: We determined that HEYL expression was inactivated in more than 75% of HCC. In addition, overexpression of HEYL in SK-Hep 1 cells caused apoptosis by the cleavage of caspase 3 and poly (ADP-ribose) polymerase. We discovered that HEYL apoptosis was preceded by serine 15 phosphorylation and accumulation of P53. Molecular analysis revealed that HEYL overexpression led to increased p16, p19, p21, p27 and Bad protein expression, and reduced c-Myc, Bcl-2 and Cyclin B1 expression. Epigenetic silencing of HEYL expression by DNA hypermethylation in HCC directly correlated with loss of HEYL expression in HCC. CONCLUSION: HEYL is frequently downregulated by promoter methylation in HCC. HEYL may be a tumor suppressor of liver carcinogenesis through upregulation of P53 gene expression and activation of P53-mediated apoptosis.

Chemokine (C-C Motif) Ligand 5 is Involved in Tumor-Associated Dendritic Cell-Mediated Colon Cancer Progression Through Non-Coding RNA MALAT-1.

Tumor micro-environment is a critical factor in the development of cancer. The aim of this study was to investigate the inflammatory cytokines secreted by tumor-associated dendritic cells (TADCs) that contribute to enhanced migration, invasion, and epithelial-to-mesenchymal transition (EMT) in colon cancer. The administration of recombinant human chemokine (C-C motif) ligand 5 (CCL5), which is largely expressed by colon cancer surrounding TADCs, mimicked the stimulation of TADC-conditioned medium on migration, invasion, and EMT in colon cancer cells. Blocking CCL5 by neutralizing antibodies or siRNA transfection diminished the promotion of cancer progression by TADCs. Tumor-infiltrating CD11c(+) DCs in human colon cancer specimens were shown to produce CCL5. The stimulation of colon cancer progression by TADC-derived CCL5 was associated with the up-regulation of non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1), which subsequently increased the expression of Snail. Blocking MALAT-1 significantly decreased the TADC-conditioned medium and CCL5-mediated migration and invasion by decreasing the enhancement of Snail, suggesting that the MALAT-1/Snail pathway plays a critical role in TADC-mediated cancer progression. In conclusion, the inhibition of CCL5 or CCL5-related signaling may be an attractive therapeutic target in colon cancer patients.

Activation of VCAM-1 and its associated molecule CD44 leads to increased malignant potential of breast cancer cells.

VCAM-1 (CD106), a transmembrane glycoprotein, was first reported to play an important role in leukocyte adhesion, leukocyte transendothelial migration and cell activation by binding to integrin VLA-1 (α4ß1). In the present study, we observed that VCAM-1 expression can be induced in many breast cancer epithelial cells by cytokine stimulation in vitro and its up-regulation directly correlated with advanced clinical breast cancer stage. We found that VCAM-1 over-expression in the NMuMG breast epithelial cells controls the epithelial and mesenchymal transition (EMT) program to increase cell motility rates and promote chemoresistance to doxorubicin and cisplatin in vitro. Conversely, in the established MDAMB231 metastatic breast cancer cell line, we confirmed that knockdown of endogenous VCAM-1 expression reduced cell proliferation and inhibited TGFß1 or IL-6 mediated cell migration, and increased chemosensitivity. Furthermore, we demonstrated that knockdown of endogenous VCAM-1 expression in MDAMB231 cells reduced tumor formation in a SCID xenograft mouse model. Signaling studies showed that VCAM-1 physically associates with CD44 and enhances CD44 and ABCG2 expression. Our findings uncover the possible mechanism of VCAM-1 activation facilitating breast cancer progression, and suggest that targeting VCAM-1 is an attractive strategy for therapeutic intervention.

Utilization of liquid chromatography mass spectrometry analyses to identify LKB1-APC interaction in modulating Wnt/ß-catenin pathway of lung cancer cells.

UNLABELLED: STK11/LKB1, a serine/threonine protein kinase and tumor suppressor, is a key upstream kinase of adenine monophosphate-activated protein kinase, which is a kinase involved in controlling cell polarity and maintaining cellular energy homeostasis. LKB1 is mutated in a significant number of Peutz-Jeghers syndrome (PJS) cases and sporadic cancers, and is most frequently mutated in lung adenocarcinomas; however, little is known about how LKB1 is involved in lung cancer progression. In this study, immunoprecipitation-HPLC tandem mass spectrometry (IP-LC-MS/MS) was performed to identify novel proteins interacting with LKB1 in lung cancer. Interestingly, many LKB1-interacting proteins acquired from the LC-MS/MS approach were mapped, using MetaCore pathway analysis, to the cystic fibrosis transmembrane conductance regulator activation pathway. Moreover, it was determined that LKB1 directly interacts with APC, and this LKB1-APC interaction was further confirmed by reverse immunoprecipitation assays, but GSK3ß was dispensable for the association of LKB1 and APC. Importantly, LKB1 binds to APC to suppress the Wnt/ß-catenin signaling pathway, which is known to be involved in cell proliferation and migration. Subsequent analysis of the downstream targets of the Wnt/TCF pathway led to the identification of several Wnt-regulated genes, such as CD44, COX-2, survivin, and c-Myc, whose expression levels are downregulated by LKB1. In summary, these results demonstrate that LKB1 regulates the Wnt pathway through a direct interaction with APC to suppress the tumorigenic/metastatic potential of lung tumors. IMPLICATIONS: LKB1 status influences the molecular circuitry (Wnt/ß-catenin pathway), cellular biology, and may serve as a potential therapeutic node in genetically defined subsets of lung cancer.