Differential expression of the chemokines GRO-2, GRO-3, and interleukin-8 in colon cancer and their impact on metastatic disease and survival

CXCL3 contributes to CD133(+) CSCs maintenance and forms a positive feedback regulation loop with CD133 in HCC via Erk1/2 phosphorylation

Although the chemotactic cytokine CXCL3 is thought to play an important role in tumor initiation and invasion, little is known about its function in hepatocellular carcinoma (HCC). In our previous study, we found that Ikaros inhibited CD133 expression via the MAPK pathway in HCC. Here, we showed that Ikaros may indirectly down-regulate CXCL3 expression in HCC cells, which leads to better outcomes in patients with CD133⁺ cancer stem cell (CSC) populations. CD133 overexpression induced CXCL3 expression, and silencing of CD133 down-regulated CXCL3 in HCC cells. Knockdown of CXCL3 inhibited CD133⁺ HCC CSCs’ self-renewal and tumorigenesis. The serum CXCL3 level was higher in HCC patients’ samples than that in healthy individual. HCC patients with higher CXCL3 expression displayed a poor prognosis, and a high level of CXCL3 was significantly associated with vascular invasion and tumor capsule formation. Exogenous CXCL3 induced Erk1/2 and ETS1 phosphorylation and promoted CD133 expression, indicating a positive feedback loop between CXCL3 and CD133 gene expression in HCC cells via Erk1/2 activation. Together, our findings indicated that CXCL3 might be a potent therapeutic target for HCC.

Type conversion of secretomes in a 3D TAM2 and HCC cell co-culture system and functional importance of CXCL2 in HCC

Macrophages play important roles in the tumor microenvironment, driving cancer progression and metastasis, particularly in hepatocellular carcinoma (HCC). However, few studies have assessed the exact secretome composition in HCC. In the present study, the impact of different phenotype of macrophages on HCC cells was investigated. Alternatively activated macrophages (M2) were found to significantly increase the proliferation, migration, and invasion abilities of SMMC7721 cells (all P < 0.05). M2 were then co-cultured with SMMC7721 cells to reconstruct the tumor microenvironment. Conditioned medium from 3D single cultures of M2, SMMC7721 cells, and their co-culture system were analyzed using quantitative proteomics via iTRAQ labeling combined with mass spectrometric analysis. Secretome analysis revealed a total of 159 differential secreted proteins in the co-culture system compared to the single culture systems, with 63 being up-regulated (>1.3-fold) and 96 down-regulated (<0.7-fold). CXCL2 was confirmed to have higher expression in the co-culture system and HCC tissues, and was selected for further investigation. Functional effects data suggested that recombinant human CXCL2 significantly enhanced the migration, invasion ability of SMMC7721 cells, and weakened adhesion ability. While CXCL2 neutralization and CXCR2 blockage significantly inhibited the effects of CXCL2 on SMMC7721 cells, indicating that CXCL2 may play pivotal role in HCC metastasis.

Overexpression of GRO-β is associated with an unfavorable outcome in colorectal cancer

Growth-related oncogene (GRO)-β, or chemokine (C-X-C motif) ligand 2 (CXCL2), is a member of the CXC chemokine family that may mediate various functions, including attracting neutrophils to sites of inflammation, and participating in tumorigenesis and progression. However, the expression of GRO-β in colorectal cancer (CRC) and the association with the clinical outcome of the disease remains poorly understood. In the present study, CXCL2 mRNA expression in CRC was analyzed using six independent datasets from the Oncomine microarray database. The immunohistochemical analysis of tissue microarrays (TMA) was used to characterize the expression of the GRO-β protein in CRC. The association between GRO-β expression and the clinicopathological features and prognosis of patients was determined by statistical analysis. The results indicated that GRO-β was highly expressed in CRC tissues, and that high GRO-β cytoplasmic expression was associated with the tumor location, extent of the primary tumor, and lymph node metastasis. Kaplan-Meier survival and Cox regression analysis revealed that high GRO-β expression was an independent indicator of poor prognosis for CRC patients. The results indicate that high GRO-β expression in CRC may correlate with an unfavorable outcome and facilitate cancer cell invasion and metastasis.

Overexpression of interleukins IL-17 and IL-8 with poor prognosis in colorectal cancer induces metastasis

Current evidences indicated that a group of soluble mediators called chemokines is involved in tumor growth and metastasis. The association of IL-8 with tumor cell migration was previously found, and its expression was related to angiogenesis, tumor progression, and metastasis in many kinds of carcinomas in human and animal models. Furthermore, it has been showed that IL-17 plays its role as either a proteome of tumor progression or antitumor indifferent cancer models. To investigate the messenger RNA (mRNA) expressions of IL-8 and IL-17 in patients with colorectal cancer (CRC) and non-tumor tissue, quantitative real-time PCR was used in the study. Our results showed that expression of IL-8 mRNA was significantly increased in tumor tissues (mean ± SD 3.84 ± 0.08) compared with adjacent normal mucosa (mean ± SD 1.17 ± 0.75, P = 0.001). Furthermore, a higher expression of IL-17 mRNA was found in tumor tissues (mean ± SD 2.73 ± 0.69) when compared with normal tissues (mean ± SD 1.06 ± 0.07, P = 0.001). Our findings indicated that advanced tumor-node-metastasis (TNM) stage (P = 0.024) and histological grade (poorly differentiated, P = 0.013) and distant metastasis (P = 0.001) were correlated with expression of IL-8. Moreover, high expression of IL-17 showed significant association with early stage CRC (TNM) (P = 0.038). In conclusion, the expression of IL-8 and IL-17 mRNAs was significantly increased in tumor tissues compared with adjacent normal tissues. We found that advanced TNM stage and histological grade and distant metastasis were correlated with expression of IL-8, while high expression of IL-17 showed significant association with early stage CRC (TNM) stage and overexpression of IL-8 may be associated with progression of CRC.

Gene-expression analysis of a colorectal cancer-specific discriminatory transcript set on formalin-fixed, paraffin-embedded (FFPE) tissue samples

BACKGROUND

A recently published transcript set is suitable for gene expression-based discrimination of normal colonic and colorectal cancer (CRC) biopsy samples. Our aim was to test the discriminatory power of the CRC-specific transcript set on independent biopsies and on formalin-fixed, paraffin-embedded (FFPE) tissue samples.

METHODS

Total RNA isolations were performed with the automated MagNA Pure 96 Cellular RNA Large Volume Kit (Roche) from fresh frozen biopsies stored in RNALater (CRC (n = 15) and healthy colonic (n = 15)), furthermore from FFPE specimens including CRC (n = 15) and normal adjacent tissue (NAT) (n = 15) specimens next to the tumor. After quality and quantity measurements, gene expression analysis of a colorectal cancer-specific marker set with 11 genes (CA7, COL12A1, CXCL1, CXCL2, CHI3L1, GREM1, IL1B, IL1RN, IL8, MMP3, SLC5A7) was performed with array real-time PCR using Transcriptor First Strand cDNA Synthesis Kit (Roche) and RealTime ready assays on LightCycler480 System (Roche). In situ hybridization for two selected transcripts (CA7, CXCL1) was performed on NAT (n = 3), adenoma (n = 3) and CRC (n = 3) FFPE samples.

RESULTS

Although analytical parameters of automatically isolated RNA samples showed differences between fresh frozen biopsy and FFPE samples, both quantity and the quality enabled their application in gene expression analyses. CRC and normal fresh frozen biopsy samples could be distinguished with 93.3% sensitivity and 86.7% specificity and FFPE samples with 96.7 and 70.0%, respectively. In situ hybridization could confirm the upregulation of CXCL1 and downregulation of CA7 in colorectal adenomas and tumors compared to healthy controls.

CONCLUSION

According to our results, gene expression analysis of the analyzed colorectal cancer-specific marker set can also be performed from FFPE tissue material. With the addition of an automated workflow, this marker set may enhance the objective classification of colorectal neoplasias in the routine procedure in the future.

Overexpression of Growth-Related Oncogene-β Is Associated with Tumorigenesis, Metastasis, and Poor Prognosis in Ovarian Cancer

Background. Growth-related oncogene- (GRO-) β is a member of the CXC chemokine family, which may mediate various functions, such as attracting neutrophils to sites of inflammation, regulating angiogenesis, and participating in tumorigenesis and progression. However, the expression of GRO-β in ovarian cancer and its relationship to the clinical characteristics of this disease remain poorly understood. Methods. In this study, immunohistochemical analysis using tissue microarray (TMA) was employed to evaluate the expression of GRO-β in ovarian cancer and to contrast expression with normal ovarian epithelial cells and oviduct epithelial cells. Next, we observed the correlation between GRO-β expression and clinicopathological features of ovarian cancer as well as patient outcome. Results. High GRO-β cytoplasmic expression was observed in 55.15% of patients with ovarian cancer, which was related to lymph node or other metastases (P < 0.001), ascites (P = 0.027), and International Federation of Obstetricians and Gynaecologists (FIGO) stage (P = 0.032). Kaplan-Meier survival and Cox regression analysis revealed that high GRO-β expression (P = 0.002) and high CA19-9 level (P = 0.003) were independent prognostic indicators of poor outcome in ovarian cancer. Conclusions. Overall, high GRO-β expression correlates with poor prognosis and contributes to ovarian cancer tumorigenesis and metastasis.

Inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma

AIM: To study the inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma (HCC) in nude mice.

METHODS: CBRH-7919 HCC cells were injected into the subcutaneous region of nude mice. Beginning two weeks after the challenge, tumor growth was measured every week for six weeks. The stromal microenvironment and inflammatory cell infiltration was assessed by immunohistochemistry in paired tumor and adjacent peritumoral samples, and macrophage phenotype was assessed using double-stain immunohistochemistry incorporating expression of an intracellular enzyme. A chemokine PCR array, comprised of 98 genes, was used to screen differential gene expressions, which were validated by Western blotting. Additionally, expression of identified chemokines was knocked-down by RNA interference, and the effect on tumor growth was assessed.

RESULTS: Inflammatory cell infiltrates are a key feature of adjacent peritumoral tissues with increased macrophage, neutrophil, and T cell (specifically helper and activated subsets) infiltration. Macrophages within adjacent peritumoral tissues express inducible nitric oxide synthase, suggestive of a proinflammatory phenotype. Fifty-one genes were identified in tumor tissues during the progression period, including 50 that were overexpressed (including CXCL1, CXCL2 and CXCL3) and three that were underexpressed (CXCR1, Ifg and Actb). RNA interference of CXCL1 in the CBRH-7919 cells decreased the growth of tumors in nude mice and inhibited expression of CXCL2, CXCL3 and interleukin-1β protein.

CONCLUSION: These findings suggest that CXCL1 plays a critical role in tumor growth and may serve as a potential molecular target for use in HCC therapy.

Inflammatory serum proteins are severely altered in metastatic gastric adenocarcinoma patients from the Chinese population

BACKGROUND

Inflammation is one of the major hallmarks of cancer. This study was designed to profile a panel of inflammatory mediators in gastric adenocarcinoma (GA) and to identify their potential differences separately in metastatic and non-metastatic patient subgroups.

METHODS

Serum samples from 216 GA patients and 333 healthy controls from China were analyzed for six proteins using the Luminex multiplex assay.

RESULTS

The serum levels for all the six proteins were significantly elevated in metastatic GA compared to non-metastatic GA. Two acute phase proteins (SAA and CRP) and a CXC chemokine (GRO) were significantly elevated in metastatic GA (p <0.01) but smaller changes were observed in non-metastatic GA compared to healthy controls. OPN is moderately increased in non-metastatic GA (2.05-fold) and more severely elevated in metastatic GA (3.34-fold). Surprisingly, soluble VCAM1 and AGP were significantly lower in both non-metastatic and metastatic GA patients compared to controls. Several individual proteins were shown to possess moderate diagnostic value for non-metastatic GA (AUC = 0.786, 0.833, 0.823 for OPN, sVCAM1 and AGP, respectively) and metastatic GA (AUC = 0.931, 0.720, 0.834 and 0.737 for OPN, sVCAM1, SAA and CRP, respectively). However, protein combinations further improve the diagnostic potential for both non-metastatic GA (best AUC = 0.946) and metastatic GA (best AUC = 0.963). The protein combination with best AUC value for both comparisons is OPN+sVCAM1+AGP+SAA.

CONCLUSIONS

These results suggest that several serum proteins are directly related to the severity of gastric cancer. Overall, stronger associations are observed with metastatic than non-metastatic GA as the protein changes are greater with the metastatic status. A combination of these serum proteins may serve as non-invasive markers to assess the severity status and stage of gastric cancer.

Prognostic value, clinicopathologic features and diagnostic accuracy of interleukin-8 in colorectal cancer: a meta-analysis

BACKGROUND

The prognostic value and diagnostic accuracy of Interleukin-8 (IL-8) in colorectal cancer have been assessed with several studies, but the conclusions were inconclusive. Thus we performed a meta-analysis to evaluate the impact of IL-8 expression on colorectal cancer prognosis, clinicopathologic features and diagnostic accuracy.

METHODS

Comprehensive search strategies were used to search relevant literature in the PubMed, EBSCO and the ISI Web of Science databases. The correlation between IL-8 expression and prognosis, clinicopathologic features and diagnostic accuracy was analyzed.

RESULTS

A total of 18 articles met the inclusion criteria, including 1509 patients for clinicopathologic features or prognosis evaluation and 725 participants for diagnostic evaluation. The results suggested that overexpression of IL-8 was significantly associated with poor prognosis in colorectal cancer (HR = 1.54, 95%CI 1.03-2.32), especially in Union for International Cancer Control (UICC) stage IV patients (HR = 2.28, 95%CI 1.60-3.25). With further subgroup analysis, we found that high IL-8 level in serum was significantly correlated with poor prognosis (HR = 2.13, 95%CI 1.49-3.05). In addition, significant correlations were observed between high IL-8 expression and advanced stage (OR = 3.01, 95%CI 1.98-4.56), lymphatic metastasis (OR = 2.24, 95%CI 1.39-3.63), and liver metastasis (OR = 3.47, 95%CI 1.74-6.89). Moreover, IL-8 had high diagnostic accuracy, with pooled sensitivity 0.70(95%CI 0.66-0.74), specificity 0.91(95%CI 0.86-0.94), positive likelihood ratio (LR) 7.00(95%CI 2.48-19.73), negative LR 0.24(95%CI 0.09-0.64), diagnostic OR 24.00(95%CI 5.52-104.38).

CONCLUSIONS

This study showed that IL-8 could be a potential indicator for detecting colorectal cancer and predicting prognosis. In addition, high IL-8 level was significantly correlated with advanced stage, lymphatic metastasis, liver metastasis.

Association of high expression of Groβ with clinical and pathological characteristics of unfavorable prognosis in gastrointestinal stromal tumors

GROβ (CXCL2) is a chemokine produced by endotoxin-treated macrophages that mediates inflammation and tumor development. However, little is known about GROβ expression in gastrointestinal stromal tumors (GIST) or the relationship between GROβ expression and clinical attributes of GIST. GROβ expression was examined via immunohistochemical staining of 173 GIST samples using tissue microarray. The relationship between GROβ expression and relevant patient and tumor characteristics was assessed, using chi-square tests. Univariate and multivariate analysis was carried out using the Cox regression method. High GROβ cytoplasm staining was detected in 56 (32.4%) specimens; high GROβ nuclear staining was detected in 64 (37.0%) specimens. High GROβ cytoplasm staining was significantly associated with patients' age (P = 0.043) and tumor location (P = 0.014), while high GROβ nucleus staining was significantly associated with mitotic index (P = 0.034), tumor location (P = 0.049), and AFIP-Miettinen risk classification (P = 0.048). Kaplan-Meier survival curves showed GIST patients with low GROβ cytoplasm expression (P = 0.023) and mitotic index < 6 per 50 HPFs (P = 0.026) to have a more favorable prognosis. These findings indicate that GROβ expression correlates with malignant GIST phenotypes and could be an unfavorable prognostic marker in patients with GIST.

Clinical significance of serum expression of GROβ in hepatocellular carcinoma

This study aimed to determine whether serum levels of growth-related gene product β (GROβ) were associated with clinical parameters in hepatocellular carcinoma (HCC). Using an enzyme-linked immunosorbent assay (ELISA), the serum GROβ levels of 80 HCC patients, 65 patients with benign diseases of the liver, and 60 healthy volunteers were examined. The association between serum levels of GROβ and clinical parameters of HCC was analyzed statistically. The serum GROβ levels were much lower in benign diseases and healthy volunteers than HCC, and associated with tumor node metastasis (TNM) stages, tumor size, vascular thrombosis, capsule, and Edmondson grading of HCC (p < 0.05), but not with gender, age, liver cirrhosis, or the level of AFP (p > 0.05). We have demonstrated that GROβ, as an oncogene product, contributed to tumorigenesis and metastasis of HCC.

Inconformity of CXCL3 plasma level and placenta expression in preeclampsia and its effect on trophoblast viability and invasion

As a member of the chemokine family, CXCL3 was previously known to participate in many pathophysiological events. However, whether CXCL3 stimulates trophoblast invasion as a key process of preeclampsia pathogenesis remains largely unknown. Therefore, the aim of this study was to investigate this hypothesis and determine the effect of CXCL3 on the first trimester trophoblast. Seventy gravidas were included in this study. ELISA was used to detect CXCL3 plasma levels on preeclampsia and normal pregnant groups. CXCL3 protein and mRNA levels were detected via Western blot and real-time quantitative PCR analysis after immunolocalized in human placenta. Moreover, the CXCL3 function in HTR-8/Svneo was analyzed via WST-1 assay, flow cytometry and invasion test. The plasma CXCL3 level in preeclampsia was significantly higher than that in normal pregnancy. CXCL3 expression was observed in the cytoplasm of placental trophoblasts and vascular endothelium in all groups without significant difference between maternal and fetal sides. In addition, placenta CXCL3 expression in severe preeclampsia was significantly lower than those in normal and mild PE groups. Moreover, exogenous CXCL3 can promote the proliferation and invasion of HTR-8/Svneo; however, its effect on apoptosis remains unclear. In summary, a significant abnormality of plasma CXCL3 level and placental CXCL3 expression was discovered in severe preeclampsia; CXCL3 had a function in trophoblast invasion, which indicated its participation in shallow implantation. Therefore CXCL3 might be involved in severe preeclampsia pathogenesis.

Diagnostic value of interleukin-8 in colorectal cancer: a case-control study and meta-analysis

AIM

To assess the diagnostic value of serum interleukin-8 (IL-8) in the detection of colorectal cancer (CRC).

METHODS

An original study was conducted to explore the potential value of IL-8 in CRC diagnosis. Receiver operating characteristic (ROC) analysis was performed and the area under the curve (AUC) value was calculated. PUBMED and EMBASE were searched (to October, 2013), supplemented with manual screening for relevant publications. Meta-analysis methods were applied to pool sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratios and to construct a summary receiver-operating characteristic (sROC) curve. Heterogeneity across studies was checked by the I(2) test and Deek's funnel plot method was applied to test publication bias.

RESULTS

In our original study, serum IL-8 yielded an AUC of 0.742 [95%CI: 0.635-0.849]. The sensitivity and specificity were 85.42% and 54.05%, respectively, at a cut-off value of 5.39. In this meta-analysis, we included five studies with 668 CRC patients and 374 controls and one study in our own center with 48 CRC patients and 37 controls. The pooled sensitivity and specificity of IL-8 were 0.69 (95%CI: 0.42-0.87) and 0.85 (95%CI: 0.68-0.94) for CRC detection. Besides, the area under the sROC curve was 0.86 (95%CI: 0.82-0.88). Subgroup analysis suggested that there was no heterogeneity in the Asian subgroup but some in the European subgroup. In addition, no publication bias was found according to the Deek's funnel plot asymmetry test.

CONCLUSION

Serum IL-8 is a promising biomarker for CRC detection and may become a clinically useful tool to identify high-risk patients.

Bifidobacterium bifidum PRL2010 modulates the host innate immune response

Here, we describe data obtained from transcriptome profiling of human cell lines and intestinal cells of a murine model upon exposure and colonization, respectively, with Bifidobacterium bifidum PRL2010. Significant changes were detected in the transcription of genes that are known to be involved in innate immunity. Furthermore, results from enzyme-linked immunosorbent assays (ELISAs) showed that exposure to B. bifidum PRL2010 causes enhanced production of interleukin 6 (IL-6) and IL-8 cytokines, presumably through NF-κB activation. The obtained global transcription profiles strongly suggest that Bifidobacterium bifidum PRL2010 modulates the innate immune response of the host.

Candidate markers that associate with chemotherapy resistance in breast cancer through the study on Taxotere-induced damage to tumor microenvironment and gene expression profiling of carcinoma-associated fibroblasts (CAFs)

Recently, emerging evidence has suggested that carcinoma-associated fibroblasts (CAFs) could contribute to chemotherapy resistances in breast cancer treatment. The aim of this study is to compare the gene expression profiling of CAFs before and after chemotherapy and pick up candidate genes that might associate with chemotherapy resistance and could be used as predictors of treatment response. CAFs were cultured from surgically resected primary breast cancers and identified with immunohistochemistry (IHC) and Flow cytometry (FCM). MDA-MB-231 cells were cultured as the breast cancer cell line. Cell adhesion assay, invasion assay, and proliferation assay (MTT) were performed to compare the function of MDA-MB-231 cells co-cultured with CAFs and MDA-MB-231 cells without co-culture, after chemotherapy. Totally 6 pairs of CAFs were prepared for microarray analysis. Each pair of CAFs were obtained from the same patient and classified into two groups. One group was treated with Taxotere (regarded as after chemotherapy) while the other group was not processed with Taxotere (regarded as before chemotherapy). According to our study, the primary-cultured CAFs exhibited characteristic phenotype. After chemotherapy, MDA-MB-231 cells co-cultured with CAFs displayed increasing adhesion, invasiveness and proliferation abilities, compared with MDA-MB-231 cells without CAFs. Moreover, 35 differentially expressed genes (absolute fold change >2) were identified between CAFs after chemotherapy and before chemotherapy, including 17 up-regulated genes and 18 down-regulated genes. CXCL2, MMP1, IL8, RARRES1, FGF1, and CXCR7 were picked up as the candidate markers, of which the differential expression in CAFs before and after chemotherapy was confirmed. The results indicate the changes of gene expression in CAFs induced by Taxotere treatment and propose the candidate markers that possibly associate with chemotherapy resistance in breast cancer.

Differential roles of CXCL2 and CXCL3 and their receptors in regulating normal and asthmatic airway smooth muscle cell migration

Structural cell migration plays a central role in the pathophysiology of several diseases, including asthma. Previously, we established that IL-17-induced (CXCL1, CXCL2, and CXCL3) production promoted airway smooth muscle cell (ASMC) migration, and consequently we sought to investigate the molecular mechanism of CXC-induced ASMC migration. Recombinant human CXCL1, CXCL2, and CXCL3 were used to assess migration of human primary ASMCs from normal and asthmatic subjects using a modified Boyden chamber. Neutralizing Abs or small interfering RNA (siRNA) knockdown and pharmacological inhibitors of PI3K, ERK1/2, and p38 MAPK pathways were used to investigate the receptors and the signaling pathways involved in CXC-induced ASMC migration, respectively. We established the ability of CXCL2 and CXCL3, but not CXCL1, to induce ASMC migration at the tested concentrations using normal ASMCs. We found CXCL2-induced ASMC migration to be dependent on p38 MAPK and CXCR2, whereas CXCL3-induced migration was dependent on p38 and ERK1/2 MAPK pathways via CXCR1 and CXCR2. While investigating the effect of CXCL2 and CXCL3 on asthmatic ASMC migration, we found that they induced greater migration of asthmatic ASMCs compared with normal ones. Interestingly, unlike normal ASMCs, CXCL2- and CXCL3-induced asthmatic ASMC migration was mainly mediated by the PI3K pathway through CXCR1. In conclusion, our results establish a new role of CXCR1 in ASMC migration and demonstrate the diverse mechanisms by which CXCL2 and CXCL3 mediate normal and asthmatic ASMC migration, suggesting that they may play a role in the pathogenesis of airway remodeling in asthma.

Mesenchymal stem cells tune the development of monocyte-derived dendritic cells toward a myeloid-derived suppressive phenotype through growth-regulated oncogene chemokines

Mesenchymal stem/stromal cells (MSCs) are promising potential candidates for the treatment of immunological diseases because of their immunosuppressive functions. However, the molecular mechanisms that mediate MSCs' immunosuppressive activity remain elusive. In this article, we report for the first time, to our knowledge, that secreted growth-regulated oncogene (GRO) chemokines, specifically GRO-γ, in human MSC-conditioned media have an effect on the differentiation and the function of human monocyte-derived dendritic cells. The monocyte-derived dendritic cells were driven toward a myeloid-derived suppressor cell (MDSC)-like phenotype by the GRO chemokines. GRO-γ-treated MDSCs had a tolerogenic phenotype that was characterized by an increase in the secretion of IL-10 and IL-4, and a reduction in the production of IL-12 and IFN-γ. We have also shown that the mRNA expression levels of the arginase-1 and inducible NO synthase genes, which characterize MDSCs, were upregulated by GRO-γ-primed mouse bone marrow cells. In addition, the ability of GRO-γ-treated bone marrow-derived dendritic cells to stimulate the OVA-specific CD8(+) T (OT-1) cell proliferation and the cytokine production of IFN-γ and TNF-α were significantly decreased in vivo. Our findings allow a greater understanding of how MDSCs can be generated and offer new perspectives to exploit the potential of MDSCs for alternative approaches to treat chronic inflammation and autoimmunity, as well as for the prevention of transplant rejection.

G31P, an antagonist against CXC chemokine receptors 1 and 2, inhibits growth of human prostate cancer cells in nude mice

Prostate cancer is the most common malignancy in Western countries. Chemokine C-X-C motif receptor 1 (CXCR1) and CXCR2 play a key role in generation and regulation of CXC chemokine signaling. CXCR1 is a receptor for interleukin 8 (IL8), a pro-inflammatory chemokine, and CXCR1/2 are crucially involved in the prostate cancer development and progression. Thus, we generated a high-affinity human CXCR1/CXCR2 inhibitor, CXCL8 (3-72) K11R/G31P, named G31P, which is a synthetic derivative of the human cytokine, IL-8. In this study, we investigated the effects of G31P on regulation of prostate cancer cell growth in vitro and in nude mouse xenografts. Cell viability, adhesion, and wound healing assays were used to assess the effects of G31P on growth, adhesion, and migration of PC-3 human prostate cancer cells in vitro, respectively. Nude mouse xenografts and xenograft implantation assays were performed to determine the effect of G31P on PC-3 cells in vivo. Immunohistochemistry was used to detect gene expression, and fluorescence imaging was used to detect tumor volume and microvessel density in tumor xenografts. The data showed that G31P treatment significantly reduced PC-3 cell viability, adhesion and migration capacity in a dose-dependent manner (up to 100 ng/ml). Additionally, G31P treatment of nude mice suppressed the growth of orthotopically transplanted tumor xenografts. G31P also inhibited tumor tissue vascularization, which was associated with the decreased expression of vascular endothelial growth factor and nuclear transcription factor (NF)-κB in orthotopic xenograft tissues. This study provides evidence that G31P, a CXCR1/2 inhibitor, may effectively control prostate cancer.

Diversity in sequence-dependent control of GRO chemokine mRNA half-life

Neutrophil trafficking to sites of injury or infection is regulated, in part, by the closely related GRO family of chemokines (CXCL1, -2, and -3). Expression of the GRO chemokine genes is known to be determined by transcriptional bursts in response to proinflammatory stimulation, but post-transcriptional mechanisms that regulate mRNA half-life are now recognized as important determinants. mRNA half-life is regulated via distinct sequence motifs and sequence-specific, RNA-binding proteins, whose function is subject to regulation by extracellular proinflammatory stimuli. Moreover, such mechanisms exhibit cell-type and stimulus dependency. We now present evidence that in nonmyeloid cells, GRO2 and GRO3 isoforms exhibit at least two patterns of mRNA instability that are distinguished by differential sensitivity to specific mRNA-destabilizing proteins and stimulus-mediated prolongation of mRNA half-life, respectively. Although the 3' UTR regions of GRO2 and GRO3 mRNAs contain multiple AREs, GRO2 has eight AUUUA pentamers, whereas GRO3 has seven. These confer quantitative differences in half-life and show sensitivity for TTP and KSRP but not SF2/ASF. Moreover, these AUUUA determinants do not confer instability that can be modulated in response to IL-1α. In contrast, IL-1α-sensitive instability for GRO2 and GRO3 is conferred by sequences located proximal to the 3' end of the 3'UTR that are independent of the AUUUA sequence motif. These regions are insensitive to TTP and KSRP but show reduced half-life mediated by SF2/ASF. These sequence-linked, post-transcriptional activities provide substantial mechanistic diversity in the control of GRO family chemokine gene expression.

Mice that express human interleukin-8 have increased mobilization of immature myeloid cells, which exacerbates inflammation and accelerates colon carcinogenesis

BACKGROUND & AIMS

Interleukin (IL)-8 has an important role in initiating inflammation in humans, attracting immune cells such as neutrophils through their receptors CXCR1 and CXCR2. IL-8 has been proposed to contribute to chronic inflammation and cancer. However, mice do not have the IL-8 gene, so human cancer cell lines and xenograft studies have been used to study the role of IL-8 in colon and gastric carcinogenesis. We generated mice that carry a bacterial artificial chromosome that encompasses the entire human IL-8 gene, including its regulatory elements (IL-8Tg mice).

METHODS

We studied the effects of IL-8 expression in APCmin(+/-) mice and IL-8Tg mice given azoxymethane and dextran sodium sulfate (DSS). We also examined the effects of IL-8 expression in gastric cancer in INS-GAS mice that overexpress gastrin and IL-8Tg mice infected with Helicobacter felis.

RESULTS

In IL-8Tg mice, expression of human IL-8 was controlled by its own regulatory elements, with virtually no messenger RNA or protein detectable under basal conditions. IL-8 was strongly up-regulated on systemic or local inflammatory stimulation, increasing mobilization of immature CD11b(+)Gr-1(+) myeloid cells (IMCs) with thioglycolate-induced peritonitis, DSS-induced colitis, and H. felis-induced gastritis. IL-8 was increased in colorectal tumors from patients and IL-8Tg mice compared with nontumor tissues. IL-8Tg mice developed more tumors than wild-type mice following administration of azoxymethane and DSS. Expression of IL-8 increased tumorigenesis in APCmin(+/-) mice compared with APCmin(+/-) mice that lack IL-8; this was associated with increased numbers of IMCs and angiogenesis in the tumors.

CONCLUSIONS

IL-8 contributes to gastrointestinal carcinogenesis by mobilizing IMCs and might be a therapeutic target for gastrointestinal cancers.

A systems biology approach to the global analysis of transcription factors in colorectal cancer

Background

Biological entities do not perform in isolation, and often, it is the nature and degree of interactions among numerous biological entities which ultimately determines any final outcome. Hence, experimental data on any single biological entity can be of limited value when considered only in isolation. To address this, we propose that augmenting individual entity data with the literature will not only better define the entity’s own significance but also uncover relationships with novel biological entities.

To test this notion, we developed a comprehensive text mining and computational methodology that focused on discovering new targets of one class of molecular entities, transcription factors (TF), within one particular disease, colorectal cancer (CRC).

Methods

We used 39 molecular entities known to be associated with CRC along with six colorectal cancer terms as the bait list, or list of search terms, for mining the biomedical literature to identify CRC-specific genes and proteins. Using the literature-mined data, we constructed a global TF interaction network for CRC. We then developed a multi-level, multi-parametric methodology to identify TFs to CRC.

Results

The small bait list, when augmented with literature-mined data, identified a large number of biological entities associated with CRC. The relative importance of these TF and their associated modules was identified using functional and topological features. Additional validation of these highly-ranked TF using the literature strengthened our findings. Some of the novel TF that we identified were: SLUG, RUNX1, IRF1, HIF1A, ATF-2, ABL1, ELK-1 and GATA-1. Some of these TFs are associated with functional modules in known pathways of CRC, including the Beta-catenin/development, immune response, transcription, and DNA damage pathways.

Conclusions

Our methodology of using text mining data and a multi-level, multi-parameter scoring technique was able to identify both known and novel TF that have roles in CRC. Starting with just one TF (SMAD3) in the bait list, the literature mining process identified an additional 116 CRC-associated TFs. Our network-based analysis showed that these TFs all belonged to any of 13 major functional groups that are known to play important roles in CRC. Among these identified TFs, we obtained a novel six-node module consisting of ATF2-P53-JNK1-ELK1-EPHB2-HIF1A, from which the novel JNK1-ELK1 association could potentially be a significant marker for CRC.

The lL-8 and IL-13 gene polymorphisms in inflammatory bowel disease and colorectal cancer

Inflammatory bowel diseases (IBD) and colorectal cancer (CRC) are disorders that originate from immune disturbances. In our study, we evaluated the association between the -251 T/A interleukin (IL)-8 and the -1112 C/T IL-13 polymorphisms, the risk of IBD, and CRC development. Genotypes were determined by PCR-restriction fragment length polymorphism in 191 patients with CRC, 150 subjects with IBD, and 205 healthy controls. We found an association between CRC and the presence of the -251 TA genotype and A allele of the IL-8 gene (odds ratios [ORs] 2.28 and 1.65). A similar relationship was observed between these polymorphic variants and ulcerative colitis (OR 2.05 for the -251 TA genotype and OR 1.47 for the -251 A allele) as well as Crohn's disease (ORs 3.11 and 1.56, respectively). Our research also revealed that the CT and TT genotypes of the IL-13 -1112 C/T polymorphism may be connected with a higher risk of CRC (ORs 2.28 and 1.65). The same genotypes affected the susceptibility of IBD (ORs 2.26 and 3.72). Our data showed that the IL-8 -251 T/A and IL-13 -1112 C/T polymorphisms might be associated with the IBD and CRC occurrence and might be used as predictive factors of these diseases in a Polish population.

Autocrine-regulated airway smooth muscle cell migration is dependent on IL-17-induced growth-related oncogenes

BACKGROUND

Airway smooth muscle cell (ASMC) migration is one of the proposed mechanisms underlying the increased airway smooth muscle mass seen in airway remodeling of patients with severe asthma. IL-17-related cytokines are a new subgroup of inflammatory mediators that have been suggested to play a role in regulating smooth muscle function. We hypothesized that IL-17-induced chemokine production from smooth muscle cells can contribute to migration of additional smooth muscle cells in the airways of asthmatic patients.

OBJECTIVE

We sought to investigate the effect of IL-17 on smooth muscle-derived chemokines and to examine the mechanisms involved in their production and contribution to the increase in airway smooth muscle migration.

METHODS

The effect of IL-17-induced supernatants on human ASMC migration was investigated. IL-17-induced growth-related oncogene (GRO) production and mRNA expression was assessed by using ELISA and RT-PCR, respectively. The direct effect of GROs on ASMC migration and the involvement of the CXCR2 receptor were also examined.

RESULTS

IL-17-induced supernatants promoted ASMC migration. After IL-17 stimulation, GROs were the most abundant chemokines produced from ASMCs, and blocking their effect by using neutralizing antibodies significantly inhibited ASMC migration. In addition, a combination of recombinant human GRO-α, GRO-β, and GRO-γ was able to promote significant migration of ASMCs that was mediated through the CXCR2 receptor.

CONCLUSION

These findings suggest that IL-17-induced GROs can be an important mediator of ASMC migration and therefore might contribute to the pathogenesis of airway remodeling in asthmatic patients.

Targeting IL-8 in colorectal cancer

INTRODUCTION

Colorectal cancer is the leading cause of death from gastrointestinal malignancy in the US. Chemokines and their receptors are being recognized as key regulators of cancers and increasingly as therapeutic targets for metastatic cancers, including colorectal cancer. Several studies have demonstrated that IL-8 and its receptor CXCR2 are two of the most significantly upregulated chemokines in colorectal cancer. IL-8 through binding to its receptors can act not only on inflammatory responses and infectious diseases, but also on cancer cells via their receptors to promote migration, invasion and proliferation, and in vivo angiogenesis. Therefore, IL-8 and CXCR2 may be important therapeutic targets against colorectal cancer.

AREAS COVERED

This review provides an update on the roles of IL-8 and its receptors in colorectal cancer preclinical models and translational relevance: i) Increased expression of IL-8 and/or its receptors has been characterized in colon cancer cells; ii) IL-8 signaling pathway in colorectal cancer cells; iii) targeting IL-8 expression, or receptor-targeted strategies in colorectal cancer, eliminates the redundant function of IL-8 signaling and determines the effects of suppressing IL-8 signaling on tumor progression and development.

EXPERT OPINION

IL-8 and its receptor CXCR2 may function as significant regulatory factors within the tumor microenvironment and be important therapeutic targets in colorectal cancers. Not only may they lead to antitumor properties, but also they may chemosensitize the tumor toward the current chemotherapy.

ERK2-dependent activation of c-Jun is required for nontypeable Haemophilus influenzae-induced CXCL2 upregulation in inner ear fibrocytes

The inner ear, composed of the cochlea and the vestibule, is a specialized sensory organ for hearing and balance. Although the inner ear has been known as an immune-privileged organ, there is emerging evidence indicating an active immune reaction of the inner ear. Inner ear inflammation can be induced by the entry of proinflammatory molecules derived from middle ear infection. Because middle ear infection is highly prevalent in children, middle ear infection-induced inner ear inflammation can impact the normal development of language and motor coordination. Previously, we have demonstrated that the inner ear fibrocytes (spiral ligament fibrocytes) are able to recognize nontypeable Haemophilus influenzae, a major pathogen of middle ear infection, and upregulate a monocyte-attracting chemokine through TLR2-dependent NF-κB activation. In this study, we aimed to determine the molecular mechanism involved in nontypeable H. influenzae-induced cochlear infiltration of polymorphonuclear cells. The rat spiral ligament fibrocytes were found to release CXCL2 in response to nontypeable H. influenzae via activation of c-Jun, leading to the recruitment of polymorphonuclear cells to the cochlea. We also demonstrate that MEK1/ERK2 signaling pathway is required for nontypeable H. influenzae-induced CXCL2 upregulation in the rat spiral ligament fibrocytes. Two AP-1 motifs in the 5'-flanking region of CXCL2 appeared to function as a nontypeable H. influenzae-responsive element, and the proximal AP-1 motif was found to have a higher binding affinity to nontypeable H. influenzae-activated c-Jun than that of the distal one. Our results will enable us better to understand the molecular pathogenesis of middle ear infection-induced inner ear inflammation.

Mass homozygotes accumulation in the NCI-60 cancer cell lines as compared to HapMap Trios, and relation to fragile site location

Runs of homozygosity (ROH) represents extended length of homozygotes on a long genomic distance. In oncology, it is known as loss of heterozygosity (LOH) if identified exclusively in cancer cell rather than in matched control cell. Studies have identified several genomic regions which show consistent ROH in different kinds of carcinoma. To query whether this consistency can be observed on broader spectrum, both in more cancer types and in wider genomic regions, we investigated ROH patterns in the National Cancer Institute 60 cancer cell line panel (NCI-60) and HapMap Caucasian healthy trio families. Using results from Affymetrix 500 K SNP arrays, we report a genome wide significant association of ROH regions between the NCI-60 and HapMap samples, with much a higher level of ROH (11 fold) in the cancer cell lines. Analysis shows that more severe ROH found in cancer cells appears to be the extension of existing ROH in healthy state. In the HapMap trios, the adult subgroup had a slightly but significantly higher level (1.02 fold) of ROH than did the young subgroup. For several ROH regions we observed the co-occurrence of fragile sites (FRAs). However, FRA on the genome wide level does not show a clear relationship with ROH regions.

DNA promoter methylation status and protein expression of interleukin-8 in human colorectal adenocarcinomas

BACKGROUND

Interleukin-8 (IL-8) also referred to as CXCL8, a member of the CXC chemokine family that attracts neutrophils and other leukocytes, has been associated with cancer. Angiogenesis is a prime regulator of tumour expansion and data support that IL-8 is a potent angiogenic factor. Epigenomic instability has been postulated to play a role for the development of multiple neoplasias including colorectal cancer (CRC). DNA methylation of cytosine residues in CpG dinucleotides leads to transcriptional silencing of associated genes.

METHOD

In this study, we comparatively analysed the protein expression of IL-8 in plasma, tumour and paired normal tissue and methylation status of the IL-8 gene to evaluate its impact on CRC.

RESULTS

Collectively, by using Luminex technology, we noted a significantly higher IL-8 level in cancer tissue compared to paired normal tissue and that CRC patients exhibit significantly higher plasma levels than healthy controls. Analysed by methylation-specific polymerase chain reaction, we detected IL-8 hypomethylation in 64% of the cancerous tissue cases but no hypomethylation was found in paired normal tissue. We noted that the CRC patients with IL-8 hypomethylation revealed a significant higher level of IL-8 protein in cancerous tissue, which tended to be associated with distant metastasis. We also observed that patients with distant metastasis showed a significantly higher plasma level of IL-8 in relation to patients without distant metastasis.

CONCLUSION

Our results suggest that the predominance of high plasma levels of IL-8 in patients with distant metastasis in combination with the hypomethylation of the IL-8 promoter region might be a useful marker of the disease advancement.

Dysplasia-carcinoma transition specific transcripts in colonic biopsy samples

BACKGROUND

The early molecular detection of the dysplasia-carcinoma transition may enhance the strength of diagnosis in the case of colonic biopsies. Our aims were to identify characteristic transcript sets in order to develop diagnostic mRNA expression patterns for objective classification of benign and malignant colorectal diseases and to test the classificatory power of these markers on an independent sample set.

METHODOLOGY/PRINCIPAL FINDINGS

Colorectal cancer (CRC) and adenoma specific transcript sets were identified using HGU133plus2 microarrays and 53 biopsies (22 CRC, 20 adenoma and 11 normal). Ninety-four independent biopsies (27 CRC, 29 adenoma and 38 normal) were analyzed on microarrays for testing the classificatory power of the discriminatory genes. Array real-time PCR validation was done on 68 independent samples (24 CRC, 24 adenoma and 20 normal). A set of 11 transcripts (including CXCL1, CHI3L1 and GREM1) was determined which could correctly discriminate between high-grade dysplastic adenoma and CRC samples by 100% sensitivity and 88.9% specificity. The discriminatory power of the marker set was proved to be high on independent samples in both microarray and RT-PCR analyses. 95.6% of original and 94.1% of cross-validated samples was correctly classified in discriminant analysis.

CONCLUSIONS/SIGNIFICANCE

The identified transcripts could correctly characterize the dysplasia-carcinoma transition in biopsy samples, also on a large independent sample set. These markers can establish the basis of gene expression based diagnostic classification of colorectal cancer. Diagnostic RT-PCR cards can become part of the automated routine procedure.

Down-regulation of CXCL1 inhibits tumor growth in colorectal liver metastasis

As part of ongoing studies to obtain a global picture of invasion related events in colorectal liver metastases, here, we report our findings on gene expression of the pro-angiogenic subgroup of chemokines, the CXCL-ELR+ chemokines. Apart from their pro-angiogenic and chemoattractant function, these chemokines appear to also contribute to tumor cell transformation, growth and invasion. In our nude mouse model of colorectal liver metastases, we found CXCL1,2,3,5 and 8 (IL-8) to be up-regulated in the tumor cells of the invasion front as compared to the tumor cells in the inner parts of the tumor. ShRNA mediated down-regulation of the most prominently up-regulated group member, CXCL1/gro-alpha resulted in inhibition of cell viability, invasion and proliferation. In vivo, down-regulation of CXCL1 resulted in a nearly complete prevention of tumor growth in nude mice. Mechanistically, auto-regulatory mechanisms involving NF-kappaB and Akt appear to be involved in pro-tumorigenic functions of CXCL1.

The expression and role of CXC chemokines in colorectal cancer

Cancer is a life-threatening disease world-wide and colorectal cancer is the second common cause of cancer mortality. The interaction between tumor cells and stromal cells plays a crucial role in tumor initiation and progression and is partially mediated by chemokines. Chemokines predominantly participate in the chemoattraction of leukocytes to inflammatory sites. Nowadays, it is clear that CXC chemokines and their receptors (CXCR) may also modulate tumor behavior by several important mechanisms: regulation of angiogenesis, activation of a tumor-specific immune response by attracting leukocytes, stimulation of tumor cell proliferation and metastasis. Here, we review the expression and complex roles of CXC chemokines (CXCL1 to CXCL16) and their receptors (CXCR1 to CXCR6) in colorectal cancer. Overall, increased expression levels of CXC chemokines correlate with poor prognosis.

Molecular mechanisms of liver metastasis

Colorectal cancer is the second most common cancer, and is the third leading cause of cancer-related death in Japan. The majority of these deaths is attributable to liver metastasis. Recent studies have provided increasing evidence that the chemokine-chemokine receptor system is a potential mechanism of tumor metastasis via multiple complementary actions: (a) by promoting cancer cell migration, invasion, survival and angiogenesis; and (b) by recruiting distal stromal cells (i.e., myeloid bone marrow-derived cells) to indirectly facilitate tumor invasion and metastasis. Here, we discuss recent preclinical and clinical data supporting the view that chemokine pathways are potential therapeutic targets for liver metastasis of colorectal cancer.

Prediction of metastasis and recurrence in colorectal cancer based on gene expression analysis: ready for the clinic?

Cancers of the colon and rectum, which rank among the most frequent human tumors, are currently treated by surgical resection in locally restricted tumor stages. However, disease recurrence and formation of local and distant metastasis frequently occur even in cases with successful curative resection of the primary tumor (R0). Recent technological advances in molecular diagnostic analysis have led to a wealth of knowledge about the changes in gene transcription in all stages of colorectal tumors. Differential gene expression, or transcriptome analysis, has been proposed by many groups to predict disease recurrence, clinical outcome, and also response to therapy, in addition to the well-established clinico-pathological factors. However, the clinical usability of gene expression profiling as a reliable and robust prognostic tool that allows evidence-based clinical decisions is currently under debate. In this review, we will discuss the most recent data on the prognostic significance and potential clinical application of genome wide expression analysis in colorectal cancer.

Molecular profiles and clinical outcome of stage UICC II colon cancer patients

PURPOSE

Published multigene classifiers suggesting outcome prediction for patients with stage UICC II colon cancer have not been translated into a clinical application so far. Therefore, we aimed at validating own and published gene expression signatures employing methods which enable their reconstruction in routine diagnostic specimens.

METHODS

Immunohistochemistry was applied to 68 stage UICC II colon cancers to determine the protein expression of previously published prognostic classifier genes (CDH17, LAT, CA2, EMR3, and TNFRSF11A). RNA from macrodissected tumor samples from 53 of these 68 patients was profiled on Affymetrix GeneChips (HG-U133 Plus 2.0). Prognostic signatures were generated by "nearest shrunken centroids" with cross-validation. Previously published gene signatures were applied to our data set using "global tests" and leave-one-out cross-validation

RESULTS

Correlation of protein expression with clinical outcome failed to separate patients with disease-free follow-up (group DF) and relapse (group R). Although gene expression profiling allowed the identification of differentially expressed genes ("DF" vs. "R"), a stable classification/prognosis signature was not discernable. Furthermore, the application of previously published gene signatures to our data was unable to predict clinical outcome (prediction rate 75.5% and 64.2%; n.s.). T-stage was the only independent prognostic factor for relapse with established clinical and pathological parameters including microsatellite status (multivariate analysis).

CONCLUSIONS

Our protein and gene expression analyses do not support application of molecular classifiers for prediction of clinical outcome in current routine diagnostic as a basis for patient-orientated therapy in stage UICC II colon cancer. Further studies are needed to develop prognosis signatures applicable in patient care.

Clinical significance of serum expression of GROβ in esophageal squamous cell carcinoma

AIM: To determine the association between serum levels of growth-related gene product β (GROβ) and clinical parameters in esophageal squamous cell carcinoma (ESCC).

METHODS: Using enzyme-linked immunosorbent assay, serum GROβ levels were measured in ESCC patients (n = 72) and healthy volunteers (n = 83). The association between serum levels of GROβ and clinical parameters of ESCC was analyzed statistically.

RESULTS: The serum GROβ levels were much higher in ESCC patients than in healthy controls (median: 645 ng/L vs 269 ng/L, P < 0.05). Serum GROβ levels were correlated positively with tumor size, lymph node metastasis, and tumor-node-metastasis (TNM) staging, but not with gender or the histological grade of tumors in ESCC patients. The sensitivity and specificity of the assay for serum GROβ were 73.61% and 56.63%, respectively.

CONCLUSION: GROβ may function as an oncogene product and contribute to tumorigenesis and metastasis of ESCC.

Custom design of a GeXP multiplexed assay used to assess expression profiles of inflammatory gene targets in normal colon, polyp, and tumor tissue

Colon cancers are characterized by aberrant gene expression signatures associated with disease initiation and progression. Identification of aberrant gene expression associated with colon carcinogenesis has increased significantly with application of gene array technologies. Downstream processing of these data has been hindered by the lack of robust multiplexed gene quantitative technologies facilitating study of the identified multiple gene targets. The GenomeLab Genetic Analysis System presents a novel technology platform for quantitative multiplexed gene expression analysis. This report describes the custom design of a GeXP multiplexed assay used to assess expression profiles of 14 inflammatory gene targets in normal, polyp, and tumor tissue. Characteristic normal, polyp, and tumor tissue gene expression profiles were obtained. Statistical analysis confirmed comparable relative quantitation of gene expression using the GeXP, macroarray, and single-plex real-time polymerase chain reaction assays. GeXP assays may be usefully applied in clinical and regulatory studies of multiple gene targets. This system permits custom-design options for relative quantification of multiple gene target expression, simultaneously in a single reaction, using nanogram quantities of total RNA template. The system provides an approach to advance the study of multiple targets identified from gene array analysis with potential for characterizing gene expression signatures in clinical diagnostics.

Pathobiology of colorectal cancer hepatic metastases with an emphasis on prognostic factors

Colorectal cancer is the second leading cause of cancer related death in the United States. The majority of these deaths are due to metastasis, with the liver easily accounting as the most common site of deposit. While there are multiple steps in the CRC hepatic metastatic cascade, this review attempts to summarize the different processes involved, focusing on the most recent discoveries, as well as the associated effects in relation to prognosis.

Interleukin-8 is associated with adhesion, migration and invasion in human gastric cancer SCG-7901 cells

Interleukin-8 is known as an important chemokine involved in tumor angiogenesis and progression. Overexpression of interleukin-8 has been detected in a variety of human tumors, including gastric cancer, and is negatively correlated with prognosis. The aim of our study is to determine the effects of interleukin-8 on proliferation, adhesion, migration and invasion abilities and correlated molecular mechanisms in gastric cancer. We made recombinant interleukin-8 ranged from 0 ng/ml to 100 ng/ml interferes in human gastric cancer SCG-7901 cells in vitro. The results shown that interleukin-8 did not change cell proliferation, but promoted cell adhesion to endothelial cell and extracellular matrix components (collagen, laminin and fibronectin) as detected by Cell Counting Kit-8. And it induced migration and invasion ability based on scratch and transwell-chamber assays. Also, interleukin-8 regulated the protein and mRNA expression of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad and there was obviously a dose-dependent relationship, but the protein or mRNA expression of matrix metalloproteinase-2 was not obviously changed under the tested conditions. Our findings indicate that interleukin-8 is associated with adhesion, migration and invasion in gastric cancer and the regulation of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad expression is one of the potential molecule mechanisms. The studies imply interleukin-8 may be an alternative treatment strategy against gastric cancer.

Role of CXCL8/CXCR1 in the metastasis of human colon cancer

AIM: To investigate the expression of CXCL8 and CXCR1 in colonic mucosa of patients with colon cancer and to analyze their relationship with the metastasis of colon cancer.

METHODS: A total of 106 patients with colon cancer were included in this study. Immunohistochemistry was used to detect the expression of CXCL8 and CXCR1 in colon cancer specimens taken from these patients. The correlation of CXCL8 and CXCR1 expression with clinicopathological data for these patients, including age, sex, tumor size, lymph node metastasis and Duke stage, were analyzed.

RESULTS: The positive rates of CXCL8 and CXCR1 expression were 71.7% (86/106) and 67.0% (78/106) in colon cancer, respectively. A significant correlation was noted between CXCL8/CXCR1 expression and tumor size, lymph node metastasis, and Duke stages (all P < 0.05) though no correlation was found between CXCL8/CXCR1 expression and age, sex and pathological differentiation.

CONCLUSION: CXCL8/CXCR1 may be involved in the progression and metastasis of colon cancer and therefore can be used as new diagnostic markers for colon cancer and novel targets for therapeutic intervention of the disease.