RNA-binding proteins (RBPs) control mRNA processing, stability, transport, editing, and translation. We recently conducted transcriptome analyses comparing normal (i.e., healthy) cervical tissue samples with human papillomavirus (HPV)-positive cervical cancer tissue samples and identified 614 differentially expressed protein-coding transcripts which are enriched in cancer-related pathways and consist of 95 known RBPs. We verified the altered expression of 26 genes with a cohort of 72 cervical samples, including 24 normal cervical samples, 25 cervical intraepithelial neoplasia grade 2 (CIN2) and CIN3 samples, and 23 cervical cancer tissue samples. LY6K (lymphocyte antigen 6 complex locus K), FAM83A (family member with sequence similarity 83), CELSR3, ASF1B, IQGAP3, SEMA3F, CLDN10, MSX1, CXCL5, ASRGL1, ELAVL2, GRB7, KHSRP, NOVA1, PTBP1, and RNASEH2A were identified as novel candidate genes associated with cervical lesion progression and carcinogenesis. HPV16 or HPV18 infection was found to alter the expression of 8 RBP genes (CDKN2A, ELAVL2, GRB7, HSPB1, KHSRP, NOVA1, PTBP1, and RNASEH2A) in human vaginal and foreskin keratinocytes. Both viral E6 and E7 decreased NOVA1 expression, but only E7 increased the expression of RNASEH2A in an E2F1-dependent manner. Proliferating cell nuclear antigen (PCNA) directs RNASEH2 activity with respect to DNA replication by removing the RNA primers to promote Okazaki fragment maturation, and two factors are closely associated with neoplasia progression. Therefore, we predict that the induction of expression of RNASEH2A via viral E7 and E2F1 may promote DNA replication and cancer cell proliferation.

BACKGROUND: The current study aimed to identify potential diagnostic and prognostic gene biomarkers for colorectal cancer (CRC) based on the Gene Expression Omnibus (GEO) datasets and The Cancer Genome Atlas (TCGA) dataset.
METHODS: Microarray data of gene expression profiles of CRC from GEO and RNA-sequencing dataset of CRC from TCGA were downloaded. After screening overlapping differentially expressed genes (DEGs) by R software, functional enrichment analyses of the DEGs were performed using the DAVID database. Then, the STRING database and Cytoscape were used to construct a protein-protein interaction (PPI) network and identify hub genes. The receiver operating characteristic (ROC) curves were conducted to assess the diagnostic values of the hub genes. Cox proportional hazards regression was performed to screen the potential prognostic genes. Kaplan-Meier curve and the time-dependent ROC curve were used to assess the prognostic values of the potential prognostic genes for CRC patients.
RESULTS: Integrated analysis of GEO and TCGA databases revealed 207 common DEGs in CRC. A PPI network consisted of 70 nodes and 170 edges were constructed and top 10 hub genes were identified. The area under curve (AUC) of the ROC curves of the hub genes were 0.900, 0.927, 0.869, 0.863, 0.980, 0.682, 0.903, 0.790, 0.995, and 0.989 for CCL19, CXCL1, CXCL5, CXCL11, CXCL12, GNG4, INSL5, NMU, PYY, and SST, respectively. A prognostic gene signature consisted of 9 genes including SLC4A4, NFE2L3, GLDN, PCOLCE2, TIMP1, CCL28, SCGB2A1, AXIN2, and MMP1 was constructed with a good performance in predicting overall survivals of CRC patients. The AUC of the time-dependent ROC curve was 0.741 for 5-year survival.
CONCLUSION: The results in this study might provide some directive significance for further exploring the potential biomarkers for diagnosis and prognosis prediction of CRC patients.

BACKGROUND: Tall cell variant papillary thyroid carcinoma (TCPTC) is reportedly associated with aggressive clinicopathological parameters and poor outcomes; however, the molecular mechanisms underlying TCPTC remain poorly understood.
METHODS: The gene mutation types and mRNA expression profiles of patients with TCPTC were obtained from The Cancer Genome Atlas (TCGA) database. Differentially expressed genes (DEGs) were identified. Pathways in the interaction network and the diagnostic approaches of candidate markers for TCPTC were investigated.
RESULTS: BRAF mutation was particularly prevalent in TCPTC with a mutation frequency of 78%. TCPTC was associated with a patient age >45 years, tumor multifocality, extrathyroidal extension, a higher T stage, advanced AJCC TNM stages, BRAF V600E mutation, and poor disease-free survival. We identified 4138 TCPTC-related DEGs and 301 TCPTC-specific DEGs. Intriguingly, the gene expression pattern revealed that the dysregulated levels of both putative oncogenes and tumor suppressors in TCPTC were higher than those in classical/conventional variant PTC (cPTC). Functional enrichment analyses revealed that these DEGs were involved in several cancer-related pathways. A protein-protein interaction (PPI) network was constructed from the 301 TCPTC-specific DEGs, and 3 subnetworks, and 8 hub genes were verified. Receiver operating characteristic (ROC) analyses revealed that 6 hub genes, including COL5A1, COL1A1, COL10A1, COL11A1, CCL20, and CXCL5, could be used not only for the differential diagnosis of PTC from normal samples, but also for the differential diagnosis of TCPTC from cPTC samples.
CONCLUSIONS: Our study might provide further insights into the investigations of the tumorigenesis mechanism of TCPTC and assists in the discovery of novel candidate diagnostic markers for TCPTC.

The major types of non-small-cell lung cancer (NSCLC)-squamous cell carcinoma and adenocarcinoma-have distinct immune microenvironments. We developed a genetic model of squamous NSCLC on the basis of overexpression of the transcription factor Sox2, which specifies lung basal cell fate, and loss of the tumor suppressor Lkb1 (SL mice). SL tumors recapitulated gene-expression and immune-infiltrate features of human squamous NSCLC; such features included enrichment of tumor-associated neutrophils (TANs) and decreased expression of NKX2-1, a transcriptional regulator that specifies alveolar cell fate. In Kras-driven adenocarcinomas, mis-expression of Sox2 or loss of Nkx2-1 led to TAN recruitment. TAN recruitment involved SOX2-mediated production of the chemokine CXCL5. Deletion of Nkx2-1 in SL mice (SNL) revealed that NKX2-1 suppresses SOX2-driven squamous tumorigenesis by repressing adeno-to-squamous transdifferentiation. Depletion of TANs in SNL mice reduced squamous tumors, suggesting that TANs foster squamous cell fate. Thus, lineage-defining transcription factors determine the tumor immune microenvironment, which in turn might impact the nature of the tumor.

CXCL5 is showed a surprisingly elevated profile and implicated in tumorigenesis in several tumors. However, the expression and function of CXCL5 in uterine cervix cancer (UCC) remain largely unknown. The current study aimed to elucidate the expression pattern of CXCL5 in human UCC tissues and Hela cervix cancer cell, as well as its functions in Hela cells. Our data showed that CXCL5 and its receptor CXCR2 were expressed by Hela uterine cervix cancer cells. CXCL5 was upregulated in UCC tissues, and its overexpression was positively correlated with age, but did not correlate with clinical stages and tumor infiltration. Exogenous administration of CXCL5 and CXCL5 overexpression contributed to proliferation and migration activities of Hela cells in vitro, consistent with this, CXCL5 overexpression also promoted growth of Hela cells in a nude mouse xenograft model. At the gene level, CXCL5 overexpression regulated the expression of tumor-related genes including ERK, p-ERK, AKT, p-AKT, DIABOL, NUMB, NDRG3 and CXCR2. Taken together, CXCL5 may contribute to a dominant role in UCC progression and sever as a potential molecular therapeutic target for UCC.

BACKGROUND/AIMS: Gain-of-function of mutant p53 is associated with a high rate of lung metastasis in osteosarcoma. To investigate the mechanism of mutant p53-induced osteosarcoma metastasis, expression array analysis was performed, comparing non-metastatic osteosarcomas from p53+/- mice with metastatic osteosarcomas from p53R172H/+ mice. Onzin (Plac8) was identified as one of the genes upregulated in p53R172H/+ mouse metastatic osteosarcomas. Accordingly, we investigated the role of ONZIN in human osteosarcoma metastasis.
METHODS: ONZIN function and its downstream targets were examined in osteosarcoma cell lines. Assays related to tumorigenesis and metastasis, including cell migration, invasion, clonogenic survival, and soft agar colony formation, were performed in osteosarcoma cells. Additionally, mouse xenograft models were used to examine the role of ONZIN overpression in tumorigenesis in vivo. Lastly, 87 osteosarcoma patients were recruited to investigate the clinical relevance of ONZIN overexpression in metastasis and prognosis.
RESULTS: ONZIN overexpression enhanced osteosarcoma cell proliferation, clonogenic survival, migration, and invasion independent of p53 status. Furthermore, ONZIN overexpression induced CXCL5 upregulation and resulted in increased ERK phosphorylation, which contributed to more aggressive osteosarcoma metastatic phenotypes. More importantly, overexpression of ONZIN in human osteosarcoma patients was closely associated with lung metastasis, poor prognoses, and survival.
CONCLUSIONS: Overexpression of ONZIN promotes osteosarcoma progression and metastasis, and can serve as a clinical biomarker for osteosarcoma metastasis and prognosis.

The present study aimed to examine the effects and mechanisms of exogenous C-X-C motif chemokine 5 (CXCL5) and lentiviral CXCL5 overexpression on the regulation of malignant behaviors of prostate cancer cells in vitro and in a nude mouse xenograft model. The expression levels of CXCL5 and a number of tumor-related genes were assessed by using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), western blotting, ELISA, or immunohistochemistry in normal and cancerous prostate cells and tissues. Cell proliferation, colony formation, and Transwell assays were performed to determine the effects of exogenous, autocrine, and paracrine CXCL5 on prostate cancer cell proliferative and migratory capacity. The results indicated that CXCL5 expression was upregulated in PC‑3 and DU145 prostate cancer cells, in WPMY‑1 normal prostate stromal cells, and in RWPE‑1 prostate epithelial cells, as well as in prostate cancer tissue specimens. Exogenous CXCL5 exposure resulted in increase in prostate cancer cell proliferation, colony formation, and migration. In cells transfected with a CXCL5 overexpression vector, in cells cultured in conditioned medium from CXCL5-overexpressing WPMY cells, and in cells co-cultured with CXCL5‑OE WPMY cells prostate cancer cell malignant phenotypes were induced in an autocrine/paracrine fashion in vitro; similar results were observed in nude mouse xenografts. CXCL5 overexpression also regulated expression of tumor-related genes, including BAX, N-Myc downstream-regulated gene 3, extracellular signal-regulated kinase 1/2, C-X-C chemokine receptor type 2, interleukin 18, Bcl‑2, and caspase‑3. These data demonstrated that CXCL5 expression was upregulated in prostate cancer tissues and that exogenous CXCL5 protein exposure or CXCL5 overexpression promoted malignant phenotypes of prostate cancer cells in vitro and in vivo.

The emergence of chemoresistance greatly increases the recurrence risk for non-muscle invasive bladder cancer (NMIBC) patients, which is still a big concern of clinicians. Understanding the mechanisms of drug resistance is of great significance for preventing and reversing it. We showed here that CXC motif chemokine ligand 5 (CXCL5) was overexpressed in mitomycin C-resistant bladder cancer cell line M-RT4. Meanwhile, parental RT4 cell treated with recombinant human CXCL5 (rhCXCL5) reduced its sensitivity to mitomycin C. Conversely, knockdown CXCL5 sensitized M-RT4 cell. We further investigated the molecular mechanisms finding that epithelial mesenchymal transition (EMT) and NF-κB pathway were activated in M-RT4 cell, which could be attenuated by knockdown CXCL5. All these data indicated that CXCL5 may promote mitomycin resistance by activating EMT and NF-κB pathway. Thus, our study identifies CXCL5 as a novel chemoresistance-related marker in NMIBC, thereby providing new strategies to overcome chemoresistance for NMIBC patients.

Epithelial neutrophil-activating peptide-78 (CXCL5), a member of the subgroup of CXC-type chemokine family, is an inflammatory factor involved in the progression of lung cancer, but the underlying mechanism remains unclear. In this study, we investigated the effects of CXCL5 on proliferation and migration in non-small cell lung cancer (NSCLC) using tissue microarrays from NSCLC patients and H460 cells transfected with a CXCL5-interfered lentivirus vector or stimulated with recombinant CXCL5. We observed that the expression of CXCL5 was significantly higher in lung cancer cell lines, and high CXCL5 was associated with high chemokine (C-X-C motif) receptor 2 expression and was significantly associated with poor differentiation. The high expression of CXCL5 was associated with poor NSCLC prognosis and was an independent predictive factor. Furthermore, downregulation of CXCL5 in H460 cells significantly reduced proliferation and migration. Recombinant CXCL5 promoted H460 cell proliferation and movement by activating MAPK/ERK1/2 and PI3K/AKT signaling. Our study elucidates the important role of CXCL5 in the progression and prognosis of NSCLC. These findings suggested that CXCL5 might be a potential biomarker and novel therapeutic target for lung cancer.

Chemokines influence tumor metastasis by targeting tumor, stromal, and hematopoietic cells. Characterizing the chemokine mRNA expression profile of human primary melanoma samples, we found CXCL5 significantly up-regulated in stage T4 primary melanomas when compared to thin melanomas (T1 stage). To characterize the role of CXCL5 in melanoma progression, we established a metastasizing murine xenograft model using CXCL5-overexpressing human melanoma cells. CXCL5 had no effect on melanoma proliferation in vitro and on primary tumor growth in vivo, but CXCL5-overexpressing tumors recruited high amounts of neutrophils and exhibited significantly increased lymphangiogenesis in our severe combined immune-deficient mouse model. Recruited neutrophils were found in close proximity to or within lymphatic vessels, often in direct contact with melanoma cells. Clinically, CXCL5-overexpressing melanomas had significantly increased lymph node metastases. We were able to translate these findings to human patient samples and found a positive correlation between CXCL5 expression, numbers of neutrophils in stage T4 primary melanoma, and the occurrence of subsequent locoregional metastasis.

Individuals with inflammatory bowel disease are at high risk of developing colitis-associated cancer (CAC). Strategies to block the process from inflammatory bowel disease to CAC should be considered. In the experiment, we aim to explore the chemopreventive efficacy of the probiotic cocktail Bifico and its potential mechanism in azoxymethane and dextran sodium sulphate-induced CAC in mice. Oral pretreatment of Bifico was adopted to evaluate its protective effect. The colorectums of 35 C57BL/6 mice were collected and examined for the degree of inflammation and tumorigenesis. Comparative 16S rRNA sequencing was carried out to observe Bifico-target alterations in gene expression and microbiota structure. We found that pretreatment of Bifico alleviated intestinal inflammation and reduced tumor formation. Furthermore, we identified a subset of genes as potential targets of Bifico treatment, including CXCL1, CXCL2, CXCL3, and CXCL5, which are all ligands of C-X-C motif receptor 2 (CXCR2). The 16S rRNA sequencing showed that Bifico decreased the abundance of genera Desulfovibrio, Mucispirillum, and Odoribacter, and a bloom of genus Lactobacillus was detected. Notably, we found that an abundance of these Bifico-target taxa was significantly associated with the expression of CXCR2 ligand genes. Our studies indicate that Bifico, given orally, can ameliorate CAC in mice through intervening with the possible link between Desulfovibrio, Mucispirillum, Odoribacter, Lactobacillus, and CXCR2 signaling.

Endoplasmic reticulum (ER) stress has been reported to be associated with metastasis in many malignant tumors. PKR-like ER kinase-phosphorylated eukaryotic translation initiation factor 2α (PERK-p-eIF2α) pathway is one of the three main signal pathways in ER stress, however, its mechanism in regulating breast cancer (BC) relapse or metastasis was still not completely understood. Besides, drug resistance was an important factor influencing the effect of tumor treatment and whether PERK-p-eIF2α pathway was involved in the drug resistance to BC treatment also needs to be explored. The authors conducted survival analysis of ER stress-related genes in the The Cancer Genome Atlas (TCGA) database to find the candidate molecule and found that eIF2α was significantly correlated with relapse-free survival in BC patients, especially in the triple-negative BC (TNBC) patients. Furthermore, BC cell lines were used to study the downstream target of PERK-p-eIF2α. In this study, p-eIF2α could negatively regulate the expression of programmed death ligand 1 (PDL1) and C-X-C motif chemokine ligand 5 (CXCL5), which were important ligands of the immune cells such as T cells and myeloid-derived suppressor cells in the tumor microenvironment. Besides, p-eIF2α expression in highly metastatic human TNBC cells after treatment of carboplatin was significantly decreased. The data indicated the possible novel immune-related mechanism of PERK-p-eIF2α in regulating TNBC metastasis and drug resistance of carboplatin in highly metastatic TNBC.

BACKGROUND/AIM: Cancer stem cells (CSCs) are associated with prognosis of hepatocellular carcinoma (HCC). In our previous study, we created cDNA microarray databases on the CSC population of human HuH7 cells. In the present study, we identified genes that might serve as prognostic markers of HCC by employing existing databases.
MATERIALS AND METHODS: Expressions of glutathione S-transferase pi 1 (GSTP1), lysozyme (LYZ), C-X-C motif chemokine ligand 5 (CXCL5), interleukin-8 (IL8) and dickkopf WNT signaling pathway inhibitor 1 (DKK1), the five most highly expressed genes in the CSC cDNA microarray databases, were examined in 99 patients with HCC by real-time polymerase chain reaction (qRT-PCR), and their clinical significance was analyzed.
RESULTS: The Kaplan-Meier analysis showed that both overall and cancer-specific survival were significantly longer in patients with low DKK1 expression than in those with high DKK1 expression. The multivariate analysis revealed that overall survival was negatively associated with albumin and positively associated with alkaline phosphatase (ALP), serosal invasion and stage, and cancer-specific survival was positively associated with ALP, portal vein invasion and DKK1 mRNA.
CONCLUSION: Expression of CSC-associated DKK1 mRNA might be an unfavorable prognostic marker for patients with HCC.

CD133, a pentaspan transmembrane glycoprotein, is generally used as a cancer stem cell marker in various human malignancies, but its biological function in cancer cells, especially in glioma cells, is largely unknown. Here, we demonstrated that forced expression of CD133 increases the expression of

Current anti-VEGF therapies for colorectal cancer (CRC) provide limited survival benefit, as tumors rapidly develop resistance to these agents. Here, we have uncovered an immunosuppressive role for nonclassical Ly6Clo monocytes that mediates resistance to anti-VEGFR2 treatment. We found that the chemokine CX3CL1 was upregulated in both human and murine tumors following VEGF signaling blockade, resulting in recruitment of CX3CR1+Ly6Clo monocytes into the tumor. We also found that treatment with VEGFA reduced expression of CX3CL1 in endothelial cells in vitro. Intravital microscopy revealed that CX3CR1 is critical for Ly6Clo monocyte transmigration across the endothelium in murine CRC tumors. Moreover, Ly6Clo monocytes recruit Ly6G+ neutrophils via CXCL5 and produce IL-10, which inhibits adaptive immunity. Preventing Ly6Clo monocyte or Ly6G+ neutrophil infiltration into tumors enhanced inhibition of tumor growth with anti-VEGFR2 therapy. Furthermore, a gene therapy using a nanoparticle formulated with an siRNA against CX3CL1 reduced Ly6Clo monocyte recruitment and improved outcome of anti-VEGFR2 therapy in mouse CRCs. Our study unveils an immunosuppressive function of Ly6Clo monocytes that, to our knowledge, has yet to be reported in any context. We also reveal molecular mechanisms underlying antiangiogenic treatment resistance, suggesting potential immunomodulatory strategies to enhance the long-term clinical outcome of anti-VEGF therapies.

Colorectal cancer is a heterogeneous disease. Although many risk factors are used to predict colorectal cancer patients' prognosis after surgical resection, new prognostic factors are still needed to be defined to promote predictive efficacy of prognosis and further guide therapies. Herein, we identified the prognostic significance of CXCR2 in colorectal cancer patients. We retrospectively analysed 134 patients with colorectal cancer who underwent minimally invasive surgery between 2010 and 2011. The overall cohort was divided into a training set (n = 78) and a validation set (n = 56). We detected CXCR2 expression using immunohistochemical staining and defined the cut-off value using X-tile program. Next, we analysed the association between CXCR2 expression and clinicopathologic features in training and validation sets. High expression of CXCR2 was associated with Dukes stage (P = 0.018), tumor invasion (P = 0.018) and liver metastasis (P = 0.047). Multivariate COX regression analyses confirmed that high CXCR2 level was an independent prognostic risk factor for both overall survival and disease free survival. Kaplan-Meier survival analysis demonstrated that patients with high expression of CXCR2 had a poor overall survival and disease free survival even in low-risk group (I + II). This indicated that CXCR2 can help to refine individual risk stratification. In addition, we established Nomograms of all significant factors to predict 3- or 5-years overall survival and disease free survival. Moreover, we found the combination of CXCR2 and its ligand CXCL5 had more significant value in predicting the prognosis than single CXCR2 factor.

We examined the impact of crosstalk between the insulin receptor and G protein-coupled receptor (GPCR) signaling pathways on the regulation of Yes-associated protein (YAP) localization, phosphorylation, and transcriptional activity in the context of human pancreatic ductal adenocarcinoma (PDAC). Stimulation of PANC-1 or MiaPaCa-2 cells with insulin and neurotensin, a potent mitogenic combination of agonists for these cells, promoted striking YAP nuclear localization and decreased YAP phosphorylation at Ser

BACKGROUND: Metastasis is a major cause of death in human colorectal cancer patients. However, the contribution of chemokines in the tumor microenvironment to tumor metastasis is not fully understood.
METHODS: Herein, we examinined several chemokines in colorectal cancer patients using chemokine ELISA array. Immunohistochemistry was used to detect expression of CXCL5 in colorectal cancer patients tissues. Human HCT116 and SW480 cell lines stably transfected with CXCL5, shCXCL5 and shCXCR2 lentivirus plasmids were used in our in vitro study. Immunoblot, immunofluorescence and transwell assay were used to examine the molecular biology and morphological changes in these cells. In addition, we used nude mice to detect the influence of CXCL5 on tumor metastasis in vivo.
RESULTS: We found that CXCL5 was overexpressed in tumor tissues and associated with advanced tumor stage as well as poor prognosis in colorectal cancer patients. We also demonstrated that CXCL5 was primarily expressed in the tumor cell cytoplasm and cell membranes, which may indicate that the CXCL5 was predominantly produced by cancer epithelial cells instead of fibroblasts in the tumor mesenchyme. Additionally, overexpression of CXCL5 enhanced the migration and invasion of colorectal cancer cells by inducing the epithelial-mesenchymal transition (EMT) through activation of the ERK/Elk-1/Snail pathway and the AKT/GSK3β/β-catenin pathway in a CXCR2-dependent manner. The silencing of Snail and β-catenin attenuated CXCL5/CXCR2-enhanced cell migration and invasion in vitro. The elevated expression of CXCL5 can also potentiate the metastasis of colorectal cancer cells to the liver in vivo in nude mice intrasplenic injection model.
CONCLUSION: In conclusion, our findings support CXCL5 as a promoter of colorectal cancer metastasis and a predictor of poor clinical outcomes in colorectal cancer patients.

Local interactions between cancer cells and stroma can produce systemic effects on distant organs to govern cancer progression. Here we show that IGF2 secreted by inhibitor of differentiation (Id1)-overexpressing oesophageal cancer cells instigates VEGFR1-positive bone marrow cells in the tumour macroenvironment to form pre-metastatic niches at distant sites by increasing VEGF secretion from cancer-associated fibroblasts. Cancer cells are then attracted to the metastatic site via the CXCL5/CXCR2 axis. Bone marrow cells transplanted from nude mice bearing Id1-overexpressing oesophageal tumours enhance tumour growth and metastasis in recipient mice, whereas systemic administration of VEGFR1 antibody abrogates these effects. Mechanistically, IGF2 regulates VEGF in fibroblasts via miR-29c in a p53-dependent manner. Analysis of patient serum samples showed that concurrent elevation of IGF2 and VEGF levels may serve as a prognostic biomarker for oesophageal cancer. These findings suggest that the Id1/IGF2/VEGF/VEGFR1 cascade plays a critical role in tumour-driven pathophysiological processes underlying cancer progression.

The role of mesenchymal stem cells (MSC) in osteosarcoma (OS), the most common primary tumor of bone, has not been extensively elucidated. We have recently shown that OS is characterized by interstitial acidosis, a microenvironmental condition that is similar to a wound setting, in which mesenchymal reactive cells are activated to release mitogenic and chemotactic factors. We therefore intended to test the hypothesis that, in OS, acid-activated MSC influence tumor cell behavior. Conditioned media or co-culture with normal MSC previously incubated with short-term acidosis (pH 6.8 for 10 hr, H

Tumor-associated neutrophils are increasingly recognized for their ability to promote tumor progression, mediate resistance to therapy, and regulate immunosuppression. Evidence from various murine models has shown that the chemokine receptor CXCR2 attracts neutrophil into tumors and, therefore, represents a tractable therapeutic target. Here, we report prominent expression of a neutrophil gene signature in a subset of human pancreatic adenocarcinoma (PDA). CXCL5 was the most prominently expressed CXCR2 ligand in human PDA, and its expression was higher in PDA than in any other common tumor represented in The Cancer Genome Atlas. Using a genetically engineered mouse model of PDA, we found that tumor and stromal cells differentially expressed CXCR2 ligands, with Cxcl5 high in tumor and Cxcl2 high in stroma. Cxcl5 expression was associated with mutant Kras expression and regulated by NF-κB activation. Host CXCR2 inhibition by genetic ablation prevented neutrophil accumulation in pancreatic tumors and led to a T cell-dependent suppression of tumor growth. In the absence of neutrophils, activated and functional T cells infiltrated pancreatic tumors otherwise devoid of effector T cells. Thus, the CXCR2-ligand axis helps establish an immunosuppressive microenvironment in PDA, highlighting the potential utility of targeting this axis as a novel therapy for this deadly disease. Cancer Immunol Res; 4(11); 968-82. ©2016 AACR.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) accounts for only 3% of thyroid cancers, yet strikingly, it accounts for almost 40% of thyroid cancer deaths. Currently, no effective therapies exist. In an effort to identify ATC-specific therapeutic targets, we analyzed global gene expression data from multiple studies to identify ATC-specific dysregulated genes.
METHODS: The National Center for Biotechnology Information Gene Expression Omnibus database was searched for high-throughput gene expression microarray studies from human ATC tissue along with normal thyroid and/or papillary thyroid cancer (PTC) tissue. Gene expression levels in ATC were compared with normal thyroid or PTC using seven separate comparisons, and an ATC-specific gene set common in all seven comparisons was identified. We investigated these genes for their biological functions and pathways.
RESULTS: There were three studies meeting inclusion criteria, (including 32 ATC patients, 69 PTC, and 75 normal). There were 259 upregulated genes and 286 downregulated genes in ATC with at least two-fold change in all seven comparisons. Using a five-fold filter, 36 genes were upregulated in ATC, while 40 genes were downregulated. Of the 10 top globally upregulated genes in ATC, 4/10 (MMP1, ANLN, CEP55, and TFPI2) are known to play a role in ATC progression; however, 6/10 genes (TMEM158, CXCL5, E2F7, DLGAP5, MME, and ASPM) had not been specifically implicated in ATC. Similarly, 3/10 (SFTA3, LMO3, and C2orf40) of the most globally downregulated genes were novel in this context, while 7/10 genes (SLC26A7, TG, TSHR, DUOX2, CDH1, PDE8B, and FOXE1) have been previously identified in ATC. We experimentally validated a significant correlation for seven transcription factors (KLF16, SP3, ETV6, FOXC1, SP1, EGFR1, and MAFK) with the ATC-specific genes using microarray analysis of ATC cell lines. Ontology clustering of globally altered genes revealed that "mitotic cell cycle" is highly enriched in the globally upregulated gene set (44% of top upregulated genes, p-value <10
CONCLUSIONS: By focusing on globally altered genes, we have identified a set of consistently altered biological processes and pathways in ATC. Our data are consistent with an important role for M-phase cell cycle genes in ATC, and may provide direction for future studies to identify novel therapeutic targets for this disease.

Our previous studies on gastric cancer tissue and patient plasma samples identified several cytokines/chemokines/growth factors to be differentially expressed, compared to normal samples. In this study our aim was to understand the localization patterns of the markers in gastric tissues. We investigated the expression of PDGFRB, CCL3, MMP3, CXCL8, CXCL10, CCL20, IGFBP3, CXCL9, SPP1, CCL18, TIMP1, CCL15, CXCL5 and CCL4 in gastric tissues using Immunohistochemistry (IHC) on Tissue Microarrays (TMA). The TMA comprised of 25 apparently normal (AN), 87 paired normal (PN) and 134 gastric cancer (T) tissues. The epithelial and stromal expression of markers and their correlation with patient characteristics and outcome were analyzed. Several of the markers [PDGFRB (p<0.001), CCL3 (p<0.001), MMP3 (p<0.001), CXCL8 (p<0.001), CXCL10 (p<0.001), CCL20 (p<0.001), CXCL9 (p<0.001), CCL18 (p<0.001), TIMP1 (p=0.025), CCL15 (p<0.001)] were elevated in the stromal compartment of gastric cancers compared to AN tissues, with some having intermediate levels of expression in PN tissues. Epithelial and stromal PDGFRB (p=0.030, p=0.018) expression was associated with diffuse type gastric cancer. Stromal IGFBP3 (p=0.039), CXCL8 (p=0.008), TIMP1 (p<0.001), CCL4 (p=0.003) and SPP1 (p=0.048) expression was associated with intestinal type gastric cancer. Kaplan-Meier analysis showed higher epithelial PDGFRB (p=0.005 and p=0.004), CXCL8 (p=0.009 and p=0.007) were associated with poor disease free and overall survival. In multivariate analysis, high epithelial PDGFRB (p=0.036 and p=0.02) and SPP1 (p=0.003 and p<0.001) were independent prognostic factors for DFS and OS in patients with gastric cancer. The expression of cytokine/chemokine/growth factor markers is higher in the gastric tumor stroma compared to the normal gastric stroma and PDGFRB and SPP1 may serve as potential prognostic factors in gastric cancer.

Colorectal cancer (CRC) is a leading cause of cancer deaths. Molecularly targeted therapies (e.g. bevacizumab) have improved survival rates but drug resistance ultimately develops and newer therapies are required. We identified quininib as a small molecule drug with anti-angiogenic activity using in vitro, ex vivo and in vivo screening models. Quininib (2-[(E)-2-(Quinolin-2-yl) vinyl] phenol), is a small molecule drug (molecular weight 283.75 g/mol), which significantly inhibited blood vessel development in zebrafish embryos (p < 0.001). In vitro, quininib reduced endothelial tubule formation (p < 0.001), cell migration was unaffected by quininib and cell survival was reduced by quininib (p < 0.001). Using ex vivo human CRC explants, quininib significantly reduced the secretions of IL-6, IL-8, VEGF, ENA-78, GRO-α, TNF, IL-1β and MCP-1 ex vivo (all values p < 0.01). Quininib is well tolerated in mice when administered at 50 mg/kg intraperitoneally every 3 days and significantly reduced tumour growth of HT-29-luc2 CRC tumour xenografts compared to vehicle control. In addition, quininib reduced the signal from a α

Preclinical studies have suggested that the pancreatic tumor microenvironment both inhibits and promotes tumor development and growth. Here we establish the role of stromal fibroblasts during acinar-to-ductal metaplasia (ADM), an initiating event in pancreatic cancer formation. The transcription factor V-Ets avian erythroblastosis virus E26 oncogene homolog 2 (ETS2) was elevated in smooth muscle actin-positive fibroblasts in the stroma of pancreatic ductal adenocarcinoma (PDAC) patient tissue samples relative to normal pancreatic controls. LSL-Kras(G12D/+); LSL-Trp53(R172H/+); Pdx-1-Cre (KPC) mice showed that ETS2 expression initially increased in fibroblasts during ADM and remained elevated through progression to PDAC. Conditional ablation of Ets-2 in pancreatic fibroblasts in a Kras(G12D)-driven mouse ADM model decreased the amount of ADM events. ADMs from fibroblast Ets-2-deleted animals had reduced epithelial cell proliferation and increased apoptosis. Surprisingly, fibroblast Ets-2 deletion significantly altered immune cell infiltration into the stroma, with an increased CD8+ T-cell population, and decreased presence of regulatory T cells (Tregs), myeloid-derived suppressor cells, and mature macrophages. The mechanism involved ETS2-dependent chemokine ligand production in fibroblasts. ETS2 directly bound to regulatory sequences for Ccl3, Ccl4, Cxcl4, Cxcl5, and Cxcl10, a group of chemokines that act as potent mediators of immune cell recruitment. These results suggest an unappreciated role for ETS2 in fibroblasts in establishing an immune-suppressive microenvironment in response to oncogenic Kras(G12D) signaling during the initial stages of tumor development.

BACKGROUND: Sex steroid hormones have been reported to induce inflammation causing dysregulation of cytokines in prostate cancer cells. However, the underlying epigenetic mechanism has not well been studied. The objective of this study was to evaluate the effect of sex steroid hormones on epigenetic DNA methylation changes in prostate cancer cells using a signature PCR methylation array panel that correspond to 96 genes with biological function in the human inflammatory and autoimmune signals in prostate cancer. Of the 96-gene panel, 32 genes showed at least 10% differentially methylation level in response to hormonal treatment when compared to untreated cells. Genes that were hypomethylated included CXCL12, CXCL5, CCL25, IL1F8, IL13RAI, STAT5A, CXCR4 and TLR5; and genes that were hypermethylated included ELA2, TOLLIP, LAG3, CD276 and MALT1. Quantitative RT-PCR analysis of select genes represented in a cytokine expression array panel showed inverse association between DNA methylation and gene expression for TOLLIP, CXCL5, CCL18 and IL5 genes and treatment of prostate cancer cells with 5'-aza-2'-deoxycytidine with or without trichostatin A induced up-regulation of TOLLIP expression. Further analysis of relative gene expression of matched prostate cancer tissues when compared to benign tissues from individual patients with prostate cancer showed increased and significant expression for CCL18 (2.6-fold; p<0.001), a modest yet significant increase in IL5 expression (1.17-fold; p=0.015), and a modest increase in CXCL5 expression (1.4-fold; p=0.25). In conclusion, our studies demonstrate that sex steroid hormones can induce aberrant gene expression via differential methylation changes in prostate carcinogenesis.

Mesenchymal stromal cells (MSCs) tend to infiltrate into tumors and form a major component of the tumor microenvironment. Our previous work demonstrated that tumor necrosis factor α (TNFα)-activated MSCs significantly promoted tumor growth. However, the role of TNFα-treated MSCs in tumor metastasis remains elusive. Employing a lung metastasis model of murine breast cancer, we found that TNFα-activated MSCs strikingly enhanced tumor metastasis compared with normal MSCs. We analyzed the chemokine profiles and found that the expression of CCL5, CCR2 and CXCR2 ligands were enhanced in TNFα-activated MSCs. Using genetic or pharmacological strategies to inhibit CCL5 or CCR2, we demonstrated that CCL5 and CCR2 ligands were indispensable in supporting TNFα-activated MSCs to promote tumor metastasis. Analysis of immune cells revealed that CXCR2 ligands (CXCL1, CXCL 2 and CXCL5) expressed by TNFα-activated MSCs efficiently recruited CXCR2

Accumulating evidence suggests that carcinoma-associated fibroblasts (CAFs) influence the efficacy of endocrine therapy. Aromatase inhibitors inhibit the growth of breast tumors by inhibiting the synthesis of estrogen. However, it remains unknown whether the aromatase inhibitor letrozole has an additional impact on CAFs, which further influence the efficacy of endocrine therapy. Primary CAFs were isolated from primary estrogen receptor-positive human breast tumors. Estrogen-deprived culture medium was used to exclude the influence of steroids. In co-culture, primary cultured CAFs increased MCF7 cell adhesion, invasion, migration and proliferation, and letrozole treatment inhibited these increases, except for the increase in proliferation. In total, 258 up-regulated genes and 47 down-regulated genes with an absolute fold change >2 were identified in CAFs co-cultured with MCF7 cell after letrozole treatment. One up-regulated genes (POSTN) and seven down-regulated genes (CCL2, CCL5, CXCL1, IL-8, CXCL5, LEP and NGF) were further validated by real-time PCR. The changes in CCL2 and CXCL1 expression were further confirmed using an automated microscopic imaging-based, high content analysis platform. Although the results need further functional validation, this study is the first to describe the differential tumor-promoting phenotype of CAFs induced by letrozole and the associated gene expression alterations. Most importantly, our data revealed that down-regulation of several secreted factors (CCL2, CCL5, CXCL1 etc.) in CAFs might be partially responsible for the efficacy of letrozole.

Cyclooxygenase-2 (COX-2) and its downstream product prostaglandin E2 (PGE2 ) play a key role in generation of the inflammatory microenvironment in tumor tissues. Gastric cancer is closely associated with Helicobacter pylori infection, which stimulates innate immune responses through Toll-like receptors (TLRs), inducing COX-2/PGE2 pathway through nuclear factor-κB activation. A pathway analysis of human gastric cancer shows that both the COX-2 pathway and Wnt/β-catenin signaling are significantly activated in tubular-type gastric cancer, and basal levels of these pathways are also increased in other types of gastric cancer. Expression of interleukin-11, chemokine (C-X-C motif) ligand 1 (CXCL1), CXCL2, and CXCL5, which play tumor-promoting roles through a variety of mechanisms, is induced in a COX-2/PGE2 pathway-dependent manner in both human and mouse gastric tumors. Moreover, the COX-2/PGE2 pathway plays an important role in the maintenance of stemness with expression of stem cell markers, including CD44, Prom1, and Sox9, which are induced in both gastritis and gastric tumors through a COX-2/PGE2 -dependent mechanism. In contrast, disruption of Myd88 results in suppression of the inflammatory microenvironment in gastric tumors even when the COX-2/PGE2 pathway is activated, indicating that the interplay of the COX-2/PGE2 and TLR/MyD88 pathways is needed for inflammatory response in tumor tissues. Furthermore, TLR2/MyD88 signaling plays a role in maintenance of stemness in normal stem cells as well as gastric tumor cells. Accordingly, these results suggest that targeting the COX-2/PGE2 pathway together with TLR/MyD88 signaling, which would suppress the inflammatory microenvironment and maintenance of stemness, could be an effective preventive or therapeutic strategy for gastric cancer.