Matrix metalloproteinase 11 depletion inhibits cell proliferation in gastric cancer cells

Identification and validation of biomarkers for epithelial-mesenchymal transition-related cells to estimate the prognosis and immune microenvironment in primary gastric cancer by the integrated analysis of single-cell and bulk RNA sequencing data

BACKGROUND

The epithelial-mesenchymal transition (EMT) is associated with gastric cancer (GC) progression and immune microenvironment. To better understand the heterogeneity underlying EMT, we integrated single-cell RNA-sequencing (scRNA-seq) data and bulk sequencing data from GC patients to evaluate the prognostic utility of biomarkers for EMT-related cells (ERCs), namely, cancer-associated fibroblasts (CAFs) and epithelial cells (ECs).

METHODS

scRNA-seq data from primary GC tumor samples were obtained from the Gene Expression Omnibus (GEO) database to identify ERC marker genes. Bulk GC datasets from the Cancer Genome Atlas (TCGA) and GEO were used as training and validation sets, respectively. Differentially expressed markers were identified from the TCGA database. Univariate Cox, least-absolute shrinkage, and selection operator regression analyses were performed to identify EMT-related cell-prognostic genes (ERCPGs). Kaplan-Meier, Cox regression, and receiver-operating characteristic (ROC) curve analyses were adopted to evaluate the prognostic utility of the ERCPG signature. An ERCPG-based nomogram was constructed by integrating independent prognostic factors. Finally, we evaluated the correlations between the ERCPG signature and immune-cell infiltration and verified the expression of ERCPG prognostic signature genes by in vitro cellular assays.

RESULTS

The ERCPG signature was comprised of seven genes (COL4A1, F2R, MMP11, CAV1, VCAN, FKBP10, and APOD). Patients were divided into high- and low-risk groups based on the ERCPG risk scores. Patients in the high-risk group showed a poor prognosis. ROC and calibration curves suggested that the ERCPG signature and nomogram had a good prognostic utility. An immune cell-infiltration analysis suggested that the abnormal expression of ERCPGs induced the formation of an unfavorable tumor immune microenvironment. In vitro cellular assays showed that ERCPGs were more abundantly expressed in GC cell lines compared to normal gastric tissue cell lines.

CONCLUSIONS

We constructed and validated an ERCPG signature using scRNA-seq and bulk sequencing data from ERCs of GC patients. Our findings support the estimation of patient prognosis and tumor treatment in future clinical practice.

Identification of a Biomarker Combination for Survival Stratification in pStage II/III Gastric Cancer after Curative Resection

Simple Summary

Gastric cancer (GC) is the fifth most common cancer worldwide and the fourth most common cause of cancer-related deaths, with a high frequency of recurrence and metastasis, and a poor prognosis. This study presents a novel combination of four proteins (PDGFRB, INHBA, MMP11, and galectin-10) in GC tissues that have been identified as useful survival stratification markers in patients with pStage II/III GC after curative resection by quantitative polymerase chain reaction (qPCR), proteomic analysis, and immunohistochemistry (IHC).

Abstract

Background: We sought to identify an optimal combination of survival risk stratification markers in patients with pathological (p) stage II/III gastric cancer (GC) after curative resection. Methods: We measured the expression levels of 127 genes in pStage II/III GC tissues of two patient cohorts by quantitative polymerase chain reaction (qPCR) and the expression of 1756 proteins between two prognosis (good and poor) groups by proteomic analysis to identify candidate survival stratification markers. Further, immunohistochemistry (IHC) using tumor microarrays (TMAs) in another cohort of patients was performed to identify an optimal biomarker combination for survival stratification in GC patients. Results: secreted protein acidic and rich in cysteine (SPARC), erb-b2 receptor tyrosine kinase 2 (ERBB2), inhibin subunit beta A (INHBA), matrix metallopeptidase-11 (MMP11), tumor protein p53 (TP53), and platelet-derived growth factor receptor-beta (PDGFRB) were identified as candidate biomarkers from qPCR analysis, and SPARC and galectin-10 were obtained from the proteomic analysis. The combination of PDGFRB, INHBA, MMP11, and galectin-10 was identified as the optimal combination of survival risk stratification markers. Conclusions: A combination of four proteins in GC tissues may serve as useful survival risk stratification markers in patients with pStage II/III GC following curative resection. Our results may facilitate future multicenter prospective clinical trials.

Matrix metalloproteinase 11 (MMP11) in macrophages promotes the migration of HER2-positive breast cancer cells and monocyte recruitment through CCL2-CCR2 signaling

Matrix metalloproteinase 11 (MMP11), a member of the MMP family involved in the degradation of the extracellular matrix, has been implicated in cancer progression. Despite the stromal expression of MMP11 in breast cancer, the prognostic significance and role of MMP11 in immune or stromal cells of breast cancer remain unclear. Based on the immunohistochemical analysis of breast cancer tissues from 497 patients, we demonstrated that MMP11 expression in mononuclear inflammatory cells (predominantly macrophages) is an independent negative prognostic factor in breast cancer, whereas MMP11 expression in tumor cells and fibroblasts is not associated with patient survival. Enforced MMP11 expression in breast cancer cells did not promote cell proliferation and migration. However, MMP11-overexpressing macrophages enhanced the migration of HER2-positive (HER2+) breast cancer cells, recruitment of monocytes, and tube formation of endothelial cells. Furthermore, we found that the chemokine CCL2 secreted from MMP11-overexpressing macrophages activated the MAPK pathway via its receptor CCR2 in breast cancer cells, thereby promoting the migration of HER2+ breast cancer cells through MMP9 upregulation. We also found that MMP11 expression in macrophages was stimulated by MMP11-overepressing HER2+ breast cancer cells. Collectively, our findings provide evidence that MMP11 in macrophages may play a pro-tumoral role in HER2+ breast cancer through interaction with cancer cells, monocytes, and endothelial cells.

Expression of TIMPs and MMPs in Ovarian Tumors, Ascites, Ascites-Derived Cells, and Cancer Cell Lines: Characteristic Modulatory Response Before and After Chemotherapy Treatment

Background

The tissue inhibitors of metalloproteinase (TIMPs) and their associated metalloproteinase (MMPs) are essential regulators of tissue homeostasis and are essential for cancer progression. This study analyzed the expression of TIMP-1,-2,-3 and the associated MMPs (MMP-2,-9,-11,-14) in different Stages, Grades and World Health Organization (WHO) classifications of serous ovarian tumors, ascites, ascites-derived cells from chemo-naïve (CN) and relapsed (CR) patients, and in ovarian cancer cell lines. The status of TIMPs and associated MMPs in response to chemotherapy treatment was assessed in cancer cell lines; TCGA data was interrogated to gauge TIMPs and associated MMPs as prognostic and platinum-response indicators.

Methods

The levels of TIMP-1, -2 and -3 were assessed by immunohistochemistry. The mRNA expression of TIMPs and MMPs was quantified by real time PCR (qRT-PCR). The chemosensitivity (IC₅₀ values) to Cisplatin or Paclitaxel in cell lines was evaluated by MTT assay. The levels of TIMPs in ascites and cell lysates were analyzed by an ELISA assay.

Results

The expression of TIMP-2 was significantly upregulated in Type 2 compared to Type 1 tumors and normal/benign ovarian tissues. TIMP-3 expression was significantly enhanced in Stage III, Grade 3 and Type 2 tumors compared to normal/benign ovarian tissues. The mRNA expression of MMP-9,-11 and -14 was significantly upregulated in Stage IV compared to normal/benign ovarian tissues. The expression of TIMP-1 was highest, followed by TIMP-2 and then TIMP-3 in CN ascites. At the cellular level, TIMP-2 mRNA expression was significantly higher in CN compared to CR epithelial cells in patients. The expression of TIMP-1 and -2, MMPs and cancer stem cells (CSCs) were upregulated in response to chemotherapy treatments in cancer cell lines. Interrogation of the TCGA dataset suggests shifts in platinum responses in patients consistent with genetic alterations in TIMP-2, -3 and MMP-2, -11 genes in tumors; and decreased overall survival (OS) and progression-free survival (PFS) in patients with altered MMP-14 genes.

Conclusions

TIMPs and related MMPs are differentially expressed in serous ovarian tumors, ascites, ascites-derived cells and ovarian cancer cell lines. Chemotherapy treatment modulates expression of TIMPs and MMPs in association with increased expression of genes related to cancer stem cells.

Comprehensive Analysis of the Expression and Prognosis for MMPs in Human Colorectal Cancer

Background

Previous study implicated that genes of matrix metalloproteinase (MMP) family play an important role in tumor invasion, neoangiogenesis, and metastasis. However, the diverse expression patterns and prognostic values of 24 MMPs in colorectal cancer are yet to be analyzed.

Methods

In this study, by integrating public database and our data, we first investigated the expression levels and protein levels of MMPs in patients with colorectal cancer. Then, by using TCGA and GEO datasets, we evaluated the association of MMPs with clinicopathological parameters and prognosis of colorectal cancer. Finally, by using the cBioPortal online tool, we analyzed the alterations of MMPs and did the network and pathway analyses for MMPs and their nearby genes.

Results

We found that, MMP1, MMP3, MMP7, MMP9–MMP12, and MMP14 were consistently upregulated in public dataset and our samples. Whereas, MMP28 was consistently downregulated in public dataset and our samples. In the clinicopathological analyses, upregulated MMP11, MMP14, MMP16, MMP17, MMP19, and MMP23B were significantly associated with a higher tumor stage. In the survival analyses, upregulated MMP11, MMP14, MMP17, and MMP19 were significantly associated with a shorter progression-free survival (PFS) time and a shorter relapse-free (RFS) time.

Discussion

This study implied that MMP11, MMP14, MMP17, and MMP19 are potential targets of precision therapy for patients with colorectal cancer.

Circ_0000260 Regulates the Development and Deterioration of Gastric Adenocarcinoma with Cisplatin Resistance by Upregulating MMP11 via Targeting MiR-129-5p

Background

Cisplatin (CDDP) plays a vital role in the treatment of advanced gastric adenocarcinoma (GAC); however, the development of chemoresistance depletes the overall benefit of CDDP. This study harbored the aim to investigate the role of a novel circular RNA (circRNA), circ_0000260, in DDP-resistant GAC and provide a potential mechanism to explain its function.

Methods

The morphology of tumor tissues and normal tissues was observed by hematoxylin-eosin (HE) staining. The isolated exosomes were observed and examined using transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). The expression of circ_0000260, miR-129-5p and matrix metalloproteinase 11 (MMP11) mRNA was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels of CD63, CD81, fibronectin, vitronectin and MMP11 were detected by Western blot. Cell viability, colony formation, cell apoptosis, migration, invasion and cell adhesion were monitored by cell counting kit-8 (CCK-8) assay, colony formation assay, flow cytometry assay, scratch assay, transwell assay and cell adhesion assay, respectively. The interaction between miR-129-5p and circ_0000260 or MMP11 predicted by bioinformatics analysis was verified by dual-luciferase reporter assay. Animal experiments were performed in nude mice to explore the role of circ_0000260 in vivo.

Results

The expression of circ_0000260 was promoted in tumor tissues and serum-derived exosomes of GAC patients, and circ_0000260 expression in CDDP-resistant tumor tissues was higher than that in CDDP-sensitive tumor tissues. Circ_0000260 knockdown lessened CDDP chemoresistance, suppressed cell proliferation, migration, invasion and adhesion, and induced apoptosis. In mechanism, circ_0000260 regulated the expression of MMP11 by targeting miR-129-5p. MiR-129-5p inhibition could reverse the functions of circ_0000260 knockdown, and MMP11 knockdown could also reverse the effects of miR-129-5p inhibition. Besides, circ_0000260 knockdown attenuated CDDP resistance during tumor growth in vivo by regulating the expression of miR-129-5p and MMP11.

Conclusion

Circ_0000260 regulated CDDP chemoresistance of GAC by promoting MMP11 expression via targeting miR-129-5p.

Dysregulation of MiR-30a-3p/Gastrin Enhances Tumor Growth and Invasion throughSTAT3/MMP11 Pathway in Gastric Cancer

Background

Gastrin (GAST) is a well-known hormone regulating gastric biofunctions in the secretion of acid and maintaining its structural integrity. Furthermore, the dysregulation of GAST is also involved in the development of various forms of cancer. However, there are some limitations for illustrating the cellular regulation of GAST and its regulatory mechanisms in gastric malignant transformation and the potential epigenetic regulators systematically.

Methods

We explored the role of GAST expression in gastric cancer (GC) and normal tissues with the clinical features and investigated the potential relationship between GAST and STAT3/MMP11 pathway by gain or loss of function analyses. Besides, based on our microRNA/mRNA expression profiles, miR-30a-3p was the potential epigenetic regulator and additional experiments were performed to identify the hypothesis.

Results

Elevated GAST expression was frequently detected in GC and was associated with worse outcomes (p<0.001). And we firstly demonstrated that GAST was negatively regulated by miR-30a-3p. Moreover, GAST induced GC cell proliferation, migration and invasion mediating STAT3/MMP11 pathway in this study.

Conclusion

MiR-30a-3p was the promising suppressor gene through negatively regulating the expression of GAST, and dysregulation of GAST was a prognostic signature associated cell proliferation and metastasis through STAT3/MMP11 pathway in GC.

Matrix Metalloproteinase 11 as a Novel Tumor Promoter and Diagnostic and Prognostic Biomarker for Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Matrix metalloproteinase 11 (MMP-11) was found to be implicated in tumorigenesis in cancers. However, the significance of MMP-11 in pancreatic ductal adenocarcinoma (PDAC) is unclear.

METHODS

In the study, we detected malignant biological behaviors of pancreatic cancer after downregulation of MMP-11. Furthermore, we explored the possible mechanism, and the diagnostic value of serum MMP-11 level was analyzed in 116 patients with pathologically confirmed PDAC. In addition, we explored their prognostic value in PDAC.

RESULTS

We observed that MMP-11 could be expressed and activated in the cytoplasm of PDAC cells. Immunohistochemistry staining of PDAC tissues showed that MMP-11 was highly expressed in cancerous ductal epithelium instead of cancer stroma. We found that downregulation of MMP-11 inhibited proliferation of PDAC cell lines. The expression levels of cyclin-dependent kinase 4 and cyclin D1 were downregulated after MMP-11 knockdown. As for its clinical value, the serum level of MMP-11 was shown to be a potent promising diagnostic marker for PDAC.

CONCLUSIONS

Matrix metalloproteinase 11 may act as a tumor promoter, playing a positive role in PDAC development. Serum MMP-11 also has great potential to be a promising diagnostic marker for PDAC.

Matrix Metalloproteinase 11 Is a Potential Therapeutic Target in Lung Adenocarcinoma

Lung cancer is one of the leading causes of cancer-associated death, with the etiology largely unknown. The aim of this study was to identify key driver genes with therapeutic potentials in lung adenocarcinoma (LUAD). Transcriptome microarray data from four GEO datasets (GEO: GSE7670, GSE10072, GSE68465, and GSE43458) were jointly analyzed for differentially expressed genes (DEGs). Ontologic analysis showed that most of the upregulated DEGs enriched in collagen catabolic and fibril organization processes were regulated by matrix metalloproteinases (MMPs). Matrix metalloproteinase 11 (MMP11), the highest upregulated MMP family member in LUAD-transformed cells, acted in an autocrine manner and was significantly increased in sera of LUAD patients. MMP11 depletion severely impaired LUAD cell proliferation, migration, and invasion in vitro, in line with retarded tumor growth in xenograft models. Treatment of different human LUAD cell lines with anti-MMP11 antibody significantly retarded cell growth and migration. Administration of anti-MMP11 antibody at a dose of 1 μg/g body weight significantly suppressed tumor growth in xenograft models. These findings indicate that MMP11 is a key cancer driver gene in LUAD and is an appealing target for antibody therapy.

Circular RNA 0047905 acts as a sponge for microRNA4516 and microRNA1227-5p, initiating gastric cancer progression

Several lines of evidence suggest that circular RNAs (circRNAs) play important roles in oncogenesis and tumor progression. However, our knowledge of the role of circRNAs in gastric cancer (GC) remains limited. We investigated the possibility that circular RNA 0047905 (circRNA0047905) might act as a tumor promoter in the pathogenesis of gastric cancer by profiling miRNA expression in GC tissues and paired noncancerous mucosa tissues using miRNA microarrays. Next, a ceRNA network was constructed according to common miRNAs binding circRNAs and mRNAs. Mechanistically, we demonstrated that circRNA0047905 directly binds miR4516 and miR1227-5p, relieving suppression for targets SERPINB5 and MMP11. We observed that down-regulated circRNA0047905 expression in gastric cancer cells inhibited Akt/CREB signaling pathway activation. RNA scope in situ hybridization revealed expression of circRNA0047905 in GC. Our data suggest that circRNA0047905 is a promising target for GC diagnosis and therapy.

SPOCK1 contributes to the third-generation EGFR tyrosine kinase inhibitors resistance in lung cancer

INTRODUCTION

Explanation of the mechanism of resistance to third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and the development of a novel strategy for drug resistance are imperative in third-generation EGFR-TKIs-resistant non-small cell lung cancer (NSCLC). SPOCK1 was found to be abnormally expressed in various tumors including lung cancer, however, there was no study focused on the role of SPOCK1 in third-generation EGFR-TKIs resistant lung cancer cells.

METHODS AND RESULTS

We investigated the roles of SPOCK1 in NSCLC with third-generation EGFR-TKIs resistance. We showed that SPOCK1 was upregulated in the osimertinib-resistant lung cancer cells and knockdown of SPOCK1 inhibits osimertinib-resistant cells growth and overcomes resistance. Furthermore, we demonstrated that the SPOCK1 was higher in clinical NSCLC specimens compared with the normal lung tissues, and the higher expression of SPOCK1 correlated with poor prognosis. In addition, the overexpression of SPOCK1 in NSCLC tissues was positively correlated with MMP11 and TGFβ1.

CONCLUSION

Our study suggested that SPOCK1 could be an independent prognostic factor in NSCLC and would be a candidate for target therapy in osimertinib-resistant lung tumors.

Impact of matrix metalloproteinase-11 gene polymorphisms on development and clinicopathologcial variables of uterine cervical cancer in Taiwanese women

The purposes of this study were to examine whether there were associations among matrix metalloproteinase-11 (MMP-11) gene polymorphisms, development and clinicopathological characteristics of uterine cervical cancer as well as patient survival or not. Five single-nucleotide polymorphisms (SNPs) of the MMP-11 gene rs738791, rs738792, rs2267029, rs28382575, and rs131451 from one hundred and thirty patients with invasive cancer, 99 patients with high-grade cervical intraepithelial neoplasia (CIN) of uterine and 335 normal controls were analyzed using real-time polymerase chain reaction. Our results revealed that genotypic frequencies of CT/TT in MMP-11 SNP rs738791, with CC as a reference, tended to exhibit significantly different distributions (p=0.044, AOR: 0.63, 95% CI: 0.41-0.99) between patients with cervical invasive cancer and normal control women when controlling age. After multiple significance adjustment, the tendency becomes insignificant (Holm's adjusted p 0.176). Although CT/TT genotype of MMP-11 gene rs738791 tended to increase the risk of developing stage II disease at least (p=0.035; OR: 2.16, 95% CI: 1.05-4.44) and deep stromal invasion more than 10 mm (p=0.043; OR: 2.08, 95% CI: 1.02-4.26) with CC as a reference in patients with uterine cervical cancer. They became insignificant after multiple significance adjustment and the Holm's adjusted p values would become as 0.245 and 0.258, respectively. However, lymph node metastasis exhibited significant worse recurrence-free survival (p=0.033; HR: 2.83, 95% CI: 1.09-7.35), and overall survival (p=0.001; HR: 4.80, 95% CI: 1.82-12.62) compared to those without pelvic lymph node metastasis. In conclusion, it indicates no impact of the MMP-11 SNPs on uterine cervical cancer in Taiwanese women.

Identification of Biomarkers Correlated with the TNM Staging and Overall Survival of Patients with Bladder Cancer

Objective: To identify candidate biomarkers correlated with clinical prognosis of patients with bladder cancer (BC). Methods: Weighted gene co-expression network analysis was applied to build a co-expression network to identify hub genes correlated with tumor node metastasis (TNM) staging of BC patients. Functional enrichment analysis was conducted to functionally annotate the hub genes. Protein-protein interaction network analysis of hub genes was performed to identify the interactions among the hub genes. Survival analyses were conducted to characterize the role of hub genes on the survival of BC patients. Gene set enrichment analyses were conducted to find the potential mechanisms involved in the tumor proliferation promoted by hub genes. Results: Based on the results of topological overlap measure based clustering and the inclusion criteria, top 50 hub genes were identified. Hub genes were enriched in cell proliferation associated gene ontology terms (mitotic sister chromatid segregation, mitotic cell cycle and, cell cycle, etc.) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways (cell cycle, Oocyte meiosis, etc.). 17 hub genes were found to interact with ≥5 of the hub genes. Survival analysis of hub genes suggested that lower expression of MMP11, COL5A2, CDC25B, TOP2A, CENPF, CDCA3, TK1, TPX2, CDCA8, AEBP1, and FOXM1were associated with better overall survival of BC patients. BC samples with higher expression of hub genes were enriched in gene sets associated with P53 pathway, apical junction, mitotic spindle, G2M checkpoint, and myogenesis, etc. Conclusions: We identified several candidate biomarkers correlated with the TNM staging and overall survival of BC patients. Accordingly, they might be used as potential diagnostic biomarkers and therapeutic targets with clinical utility.

NF-κB contributes to MMP1 expression in breast cancer spheroids causing paracrine PAR1 activation and disintegrations in the lymph endothelial barrier in vitro

RELA, RELB, CREL, NFKB1 and NFKB2, and the upstream regulators NEMO and NIK were knocked-down in lymph endothelial cells (LECs) and in MDA-MB231 breast cancer spheroids to study the contribution of NF-κB in vascular barrier breaching. Suppression of RELA, NFKB1 and NEMO inhibited “circular chemo-repellent induced defects” (CCIDs), which form when cancer cells cross the lymphatic vasculature, by ~20–30%. Suppression of RELB, NFKB2 and NIK inhibited CCIDs by only ~10–15%. In MDA-MB231 cells RELA and NFKB1 constituted MMP1 expression, which caused the activation of PAR1 in adjacent LECs. The knock-down of MMP1 in MDA-MB231 spheroids and pharmacological inhibition of PAR1 in LECs inhibited CCID formation by ~30%. Intracellular Ca²⁺ release in LECs, which was induced by recombinant MMP1, was suppressed by the PAR1 inhibitor SCH79797, thereby confirming a functional intercellular axis: RELA/NFKB1 – MMP1 (MDA-MB231) – PAR1 (LEC). Recombinant MMP1 induced PAR1-dependent phosphorylation of MLC2 and FAK in LECs, which is indicative for their activity and for directional cell migration such as observed during CCID formation. The combined knock-down of the NF-κB pathways in LECs and MDA-MB231 spheroids inhibited CCIDs significantly stronger than knock-down in either cell type alone. Also the knock-down of ICAM-1 in LECs (a NF-κB endpoint with relevance for CCID formation) and knock-down of MMP1 in MDA-MB231 augmented CCID inhibition. This evidences that in both cell types NF-κB significantly and independently contributes to tumour-mediated breaching of the lymphatic barrier. Hence, inflamed tumour tissue and/or vasculature pose an additional threat to cancer progression.

Dual tumor-suppressors miR-139-5p and miR-139-3p targeting matrix metalloprotease 11 in bladder cancer

Our recent study of the microRNA (miRNA) expression signature of bladder cancer (BC) by deep‐sequencing revealed that two miRNA, microRNA‐139‐5p/microRNA‐139‐3p were significantly downregulated in BC tissues. The aim of this study was to investigate the functional roles of these miRNA and their modulation of cancer networks in BC cells. Functional assays of BC cells were performed using transfection of mature miRNA or small interfering RNA (siRNA). Genome‐wide gene expression analysis, in silico analysis and dual‐luciferase reporter assays were applied to identify miRNA targets. The associations between the expression of miRNA and its targets and overall survival were estimated by the Kaplan–Meier method. Gain‐of‐function studies showed that miR‐139‐5p and miR‐139‐3p significantly inhibited cell migration and invasion by BC cells. The matrix metalloprotease 11 gene (MMP11) was identified as a direct target of miR‐139‐5p and miR‐139‐3p. Kaplan–Meier survival curves showed that higher expression of MMP11 predicted shorter survival of BC patients (P = 0.029). Downregulated miR‐139‐5p or miR‐139‐3p enhanced BC cell migration and invasion in BC cells. MMP11 was directly regulated by these miRNA and might be a good prognostic marker for survival of BC patients.

Elevated serum levels of MMP-11 correlate with poor prognosis in colon cancer patients

BACKGROUND

Matrix metalloproteinase 11 (MMP11) has been shown to play a key role in human tumor progression and indicates poor clinical outcome in cancer patients.

OBJECTIVE

The current study aimed to evaluate the relationship between serum levels of MMP-11 and prognosis in colon cancer patients.

METHODS

Serum levels of MMP-11 were determined in 92 colon cancer patients and 92 healthy individuals using an enzyme-linked immunosorbent assay (ELISA). Associations between serum MMP-11 levels and clinicopathological characteristics of the patients and their outcomes were investigated. Survival analyses were performed to measure the 5-year overall survival (OS) and disease-free survival (DFS).

RESULTS

Serum MMP-11 levels were substantially higher in colon cancer patients than in healthy controls. Moreover, serum MMP-11 levels were significantly higher in patients with advanced T status, lymph node metastasis, distant metastasis, and a higher TNM stage. Elevated serum levels of MMP-11 were identified as an independent prognostic factor for 5-year mortality and adverse events associated with colon cancer. Multivariate Cox regression analysis identified the serum MMP-11 level as an independent predictor of OS and DFS.

CONCLUSION

Our study established that high serum levels of MMP-11 are associated with poor clinical outcome and may serve as a prognostic biomarker in colon cancer patients.

Influence of Immune Myeloid Cells on the Extracellular Matrix During Cancer Metastasis

The extracellular matrix (ECM) is one of the most important components within the tumor microenvironment that supports cancer development and metastasis. Under normal physiological conditions, the ECM is a tightly regulated network providing structural and biochemical support. However, the ECM becomes highly disorganized during neoplastic progression and consequently, stimulates cancer cell transformation, growth and spread. Cancer development and progression is also known to greatly benefit from the support of immune myeloid cells, which have multiple pro-tumorigenic functions including promoting tumor growth, migration and invasion, stimulating angiogenesis and suppressing anti-tumor responses. An increasing number of studies have shown that myeloid cells alter the ECM to support metastatic cancer progression and in turn, the ECM can influence the function of infiltrating myeloid cells. However, the exact nature of this relationship, such as the mechanisms employed and their molecular targets remains unclear. This review discusses evidence for the reciprocal dependence of myeloid cells and the tumor ECM for efficient tumor development and explores potential mechanisms involved in these interactions. A better understanding of this relationship has exciting implications for the development of new therapeutic treatments for metastatic cancer.

Insights into the distinct roles of MMP-11 in tumor biology and future therapeutics (Review)

The biological processes of cancer cells such as tumorigenesis, proliferation, angiogenesis, apoptosis and invasion are greatly influenced by the surrounding microenvironment. The ability of solid malignant tumors to alter the microenvironment represents an important characteristic through which tumor cells are able to acquire specific functions necessary for their malignant biological behaviors. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases with the capacity of remodeling extracellular matrix (ECM) by degrading almost all ECM proteins, which plays essential roles during the invasion and metastasis process of solid malignant tumors, including allowing tumor cells to modify the ECM components and release cytokines, ultimately facilitating protease-dependent tumor progression. MMP-11, also named stromelysin-3, is a member of the stromelysin subgroup belonging to MMPs superfamily, which has been detected in cancer cells, stromal cells and adjacent microenvironment. Differently, MMP-11 exerts a dual effect on tumors. On the one hand MMP-11 promotes cancer development by inhibiting apoptosis as well as enhancing migration and invasion of cancer cells, on the other hand MMP-11 plays a negative role against cancer development via suppressing metastasis in animal models. Overexpression of MMP-11 was discovered in sera of cancer patients compared with normal control group as well as in multiple tumor tissue specimens, such as gastric cancer, breast cancer, and pancreatic cancer. At present, some evidence supports that MMP-11 may work as a significant tumor biomarker for early detection of cancer, tumor staging, prognostic analysis, monitoring recurrence during follow-up and also a potential target for immunotherapy against cancer. In view of the importance of MMP-11 in modifying tumor microenvironment and potent antitumoral effects on solid tumors, there is an urgent need for a deeper understanding of how MMP-11 modulates tumor progression, and exploring its potential clinical application.

Complement and macrophage crosstalk during process of angiogenesis in tumor progression

The complement system, which contains some of the most potent pro-inflammatory mediators in the tissue including the anaphylatoxins C3a and C5a are the vital parts of innate immunity. Complement activation seems to play a more critical role in tumor development, but little attention has been given to the angiogenic balance of the activated complement mediators and macrophage polarization during tumor progression. The tumor growth mainly supported by the infiltration of M2- tumor-associated macrophages, and high levels of C3a and C5a, whereas M1-macrophages contribute to immune-mediated tumor suppression. Macrophages express a cognate receptors for both C3a and C5a on their cell surface, and specific binding of C3a and C5a affects the functional modulation and angiogenic properties. Activation of complement mediators induce angiogenesis, favors an immunosuppressive microenvironment, and activate cancer-associated signaling pathways to assist chronic inflammation. In this review manuscript, we highlighted the specific roles of complement activation and macrophage polarization during uncontrolled angiogenesis in tumor progression, and therefore blocking of complement mediators would be an alternative therapeutic option for treating cancer.

High level of plasma matrix metalloproteinase-11 is associated with clinicopathological characteristics in patients with oral squamous cell carcinoma

Background

Matrix metalloproteinase-11 (MMP-11) is reported to be overexpressed in several cancers and may contribute to tumorigenesis. The current study investigated the association between the clinicopathological characteristics and plasma level of MMP-11 in oral squamous cell carcinoma (OSCC) patients.

Methodology and Principal Findings

The plasma MMP-11 concentration was determined by ELISA on 330 male OSCC patients. In addition, the metastatic effects of the MMP-11 knockdown on the oral cancer cells were investigated by cell migration assay. Our results showed that the plasma MMP-11 levels were significantly higher in patients with advanced T status (p = 0.001), lymph node metastasis (p = 0.006) and higher TNM stages (p<0.001). Moreover, treatment with the MMP-11 shRNA exerted an inhibitory effect on migration in SCC9 oral cancer cells.

Conclusion

Our study showed that plasma level of MMP-11 may be useful for assessment of the disease progression, especially lymph node metastasis, in patients with OSCC.

Circulating MMP11 and specific antibody immune response in breast and prostate cancer patients

Background

Tumor Associated Antigens are characterized by spontaneous immune response in cancer patients as a consequence of overexpression and epitope-presentation on MHC class I/II machinery. Matrix Metalloprotease 11 (MMP11) expression has been associated with poor prognosis for several cancer types, including breast and prostate cancer.

Methods

MMP11 expression was determined by immunoistochemistry in breast and prostate cancer samples. Circulating MMP11 protein as well as the spontaneous immune responses against MMP11 were analyzed in a set of breast and prostate cancer patients.

Results

In plasma samples MMP11 protein was present in 5/13 breast cancer patients and in 1/12 prostate cancer patients. An antibody response was observed in 7/13 breast cancer patients and in 3/12 prostate cancer patients.

Conclusions

These findings further suggest MMP11 as a promising biomarker for these tumor types and a suitable target for cancer immunotherapy strategies.

Knockdown of MMP11 inhibits proliferation and invasion of gastric cancer cells

Matrix metalloproteinase 11 (MMP11 or stromelysin-3) has recently been reported to play a crucial role in the development and progression of multiple malignancies. The aim of this study was to investigate the function of MMP11 expression in human gastric adenocarcinoma (GAC). Using immunohistochemistry assay, we studied the expression level of MMP11 in GAC and adjacent non-cancerous tissues (ANCT). The association between MMP11 expression and tumor size and pathological grade, as well as metastatic potential was analyzed. Through small hairpin RNA (shRNA)-mediated MMP11 knockdown in SGC-7901 GAC cells, we observed the changes of the biological behaviors of GAC cells. Our results indicated that the rate of positive expression of MMP11 was higher in GAC tissues than in ANCT (55.0 vs 30.0 percent, P=0.025). MMP11 expression had no association with the factors of age or gender of the GAC patients, or the size, pathological staging and lymph node metastases of the tumors (each P greater than 0.05). Furthermore, MMP11 knockdown inhibited the proliferative activities and invasive potential of SGC-7901 GAC cells with decreased expression of IGF-1, PCNA and VEGF. Taken together, our findings demonstrated that MMP11 expression was increased in GAC tissues, but did not correlate with the clinicopathologic features. Knockdown of MMP11 expression could inhibit the proliferation and invasion of GAC cells probably through down-regulation of the IGF-1 signaling pathway, suggesting that MMP11 might be a potential therapeutic target for the treatment of gastric cancer.

Knockdown of hypoxia-inducible factor-1α accelerates peritoneal dissemination via the upregulation of MMP-1 expression in gastric cancer cell lines

This study was performed to clarify the role of hypoxia-inducible factor-1 α (HIF-1α) in the development of peritoneal dissemination in a xenograft mouse model of gastric cancer. HIF-1α knockdown (KD) and control (SC) gastric cancer cells, which were established using the MKN45 and MKN74 cell lines, were studied. The two paired cell lines were directly inoculated into the peritoneal cavity of nude mice. The number and the weight of disseminated nodules were compared between tumors generated from the KD and SC cells. In addition, the molecular mechanism was addressed through analysis of the expression levels of metastasis-related genes. The MKN45-KD cell line demonstrated significantly greater numbers of disseminated nodules and formed a larger tumor mass than the MKN45-SC cell line (p<0.05). MKN74-KD cells also tended to induce a greater number of nodules and to produce those with a heavier weight than the SC cells. An in vitro adhesion assay revealed differing results regarding the adhesion activity to extracellular matrix and monolayer mesothelium cells of the gastric cancer cells derived from the various parental cells. However, the expression of MMP-1 mRNA in the disseminated nodules was significantly increased in the KD cells compared to the SC cells derived from the two parental cell lines (p<0.01). An immunohisto-chemical study further demonstrated that there was stronger staining for MMP-1 in the MKN74-KD in comparison to MKN74-SC cells. Loss of HIF-1α may contribute to the development of aggressive peritoneal dissemination via the upregulation of MMP-1 in gastric cancer cells.

Let-7c functions as a metastasis suppressor by targeting MMP11 and PBX3 in colorectal cancer

Accumulating evidence shows that microRNAs, functioning as either oncogenes or tumour suppressors by negatively regulating downstream target genes that are actively involved in tumour initiation and progression, may be promising biomarkers and therapy targets. Data mining through a microRNA chip database indicated that let-7c may be associated with tumour metastasis. Here, we confirmed that down-regulation of let-7c in primary cancer tissues was significantly associated with metastases, advanced TNM stages and poor survival of colorectal cancer patients. Moreover, ectopic expression of let-7c in a highly metastatic Lovo cell line remarkably suppressed cell migration and invasion in vitro by the down-regulation of K-RAS, MMP11 and PBX3, as well as tumour growth and metastases in vivo, whereas inhibition of let-7c in low-metastatic HT29 cells increased cell motility and invasion by the enhanced gene expression of K-RAS, MMP11 and PBX3. Interestingly, the luciferase reporters' activities with the 3'-UTRs of K-RAS, MMP11 and PBX3 were inhibited significantly by let-7c. Importantly, rescue experiments involving the over-expression of these genes without their 3'-UTRs completely reversed the effects of let-7c on tumour metastasis, both in vitro and in vivo. Finally, the levels of let-7c were inversely correlated with those of MMP11 and PBX3, but not with those of K-RAS. Taken together, these results demonstrate that let-7c, apart from its tumour growth suppression role, also functions as a tumour metastasis suppressor in colorectal cancer by directly destabilizing the mRNAs of MMP11 and PBX3 at least.

Serum levels of MMP-11 correlate with clinical outcome in Chinese patients with advanced gastric adenocarcinoma

Background

The aim of the present study was to investigate the association between serum levels of matrix metalloproteinase 11 (MMP-11) and responses to front-line chemotherapy and prognosis in advanced unresectable gastric adenocarcinoma.

Methods

Clinical data concerning 86 patients with advanced gastric adenocarcinoma (stages III c to IV), treated in Beijing Chao-Yang Hospital from 2005 to 2009, were reviewed retrospectively. Adenocarcinoma was confirmed by pathology and patients received 5-fluorouracil-based front-line combination chemotherapy with third generation chemotherapeutic agents including paclitaxel, docetaxel and oxaliplatin. The regimen was repeated every two to three weeks, and the first evaluation was carried out after three cycles. The median cycle of chemotherapy was 6 (ranging from three to twelve cycles). Serum MMP-11 protein from the 86 patients was examined using enzyme-linked-immunosorbent-assay (ELISA) prior to chemotherapy and after three cycles of chemotherapy. Serum samples from healthy individuals were used as controls.

Results

The response rate (RR, complete response plus partial response) to chemotherapy in the 86 patients was 44.2% (38/86). The median TTP (time to progression) and overall survival (OS) in patients who responded to chemotherapy were 6.0 and 10.0 months, respectively. The response rate to chemotherapy in patients with high levels of serum MMP-11 (42.9%; 9/21) was similar to that in patients with low levels (44.6%; 29/65) (P = 0.935). Patients with low serum levels of MMP-11 had a higher median survival time and 1-year survival rate than those with high levels (11 months vs. 8 months, 50.2% vs. 21.7%, P = 0.017), although the TTP was comparable in all patients, irrespective of serum MMP-11 level (P = 0.178). Serum MMP-11 levels were correlated with lymph node metastasis (P = 0.006). Cox multivariate regression analysis demonstrated that the serum level of MMP-11 was an independent prognostic factor for patients presenting with advanced gastric carcinoma.

Conclusions

Serum levels of MMP-11 in Chinese patients with advanced gastric carcinoma were not associated with the response to front-line chemotherapy, but could play an important role in lymph node metastasis and prognosis.

Serum levels of MMP-11 correlate with clinical outcome in Chinese patients with advanced gastric adenocarcinoma

BACKGROUND

The aim of the present study was to investigate the association between serum levels of matrix metalloproteinase 11 (MMP-11) and responses to front-line chemotherapy and prognosis in advanced unresectable gastric adenocarcinoma.

METHODS

Clinical data concerning 86 patients with advanced gastric adenocarcinoma (stages III c to IV), treated in Beijing Chao-Yang Hospital from 2005 to 2009, were reviewed retrospectively. Adenocarcinoma was confirmed by pathology and patients received 5-fluorouracil-based front-line combination chemotherapy with third generation chemotherapeutic agents including paclitaxel, docetaxel and oxaliplatin. The regimen was repeated every two to three weeks, and the first evaluation was carried out after three cycles. The median cycle of chemotherapy was 6 (ranging from three to twelve cycles). Serum MMP-11 protein from the 86 patients was examined using enzyme-linked-immunosorbent-assay (ELISA) prior to chemotherapy and after three cycles of chemotherapy. Serum samples from healthy individuals were used as controls.

RESULTS

The response rate (RR, complete response plus partial response) to chemotherapy in the 86 patients was 44.2% (38/86). The median TTP (time to progression) and overall survival (OS) in patients who responded to chemotherapy were 6.0 and 10.0 months, respectively. The response rate to chemotherapy in patients with high levels of serum MMP-11 (42.9%; 9/21) was similar to that in patients with low levels (44.6%; 29/65) (P = 0.935). Patients with low serum levels of MMP-11 had a higher median survival time and 1-year survival rate than those with high levels (11 months vs. 8 months, 50.2% vs. 21.7%, P = 0.017), although the TTP was comparable in all patients, irrespective of serum MMP-11 level (P = 0.178). Serum MMP-11 levels were correlated with lymph node metastasis (P = 0.006). Cox multivariate regression analysis demonstrated that the serum level of MMP-11 was an independent prognostic factor for patients presenting with advanced gastric carcinoma.

CONCLUSIONS

Serum levels of MMP-11 in Chinese patients with advanced gastric carcinoma were not associated with the response to front-line chemotherapy, but could play an important role in lymph node metastasis and prognosis.

Abnormal expression of early growth response 1 in gastric cancer: association with tumor invasion, metastasis and heparanase transcription

Given that previous studies indicated that early growth response 1 (EGR1) exerts pro-tumorigenic effects through regulating heparanase (HPA) transcription, it was hypothesized that EGR1 may correlate with the progression of gastric cancer. One hundred and fifteen patients with gastric cancer were evaluated for the protein and transcript expression of EGR1 and HPA on immunohistochemistry and real-time quantitative polymerase chain reaction (PCR). In normal gastric mucosa, EGR1 protein expression was absent or weak, whereas gastric cancer was positive for EGR1. Seventy gastric cancer patients (60.9%) were positive for cytoplasmic EGR1 expression, and 26 (22.6%) had nuclear expression of EGR1. In the gastric cancer examined, the transcripts of EGR1 were enhanced compared to that of normal gastric mucosa, and positively correlated with EGR1 protein expression. The cytoplasmic or nuclear expression of EGR1 and its transcripts in gastric cancer was positively correlated with tumor infiltration (P < 0.05), lymph node and distant metastasis (P < 0.05), tumor node metastasis (TNM) stages (P < 0.05), but not with age, gender, tumor location and size, histological types or differentiation. Moreover, the protein and transcript expression of EGR1 was correlated with that of HPA in gastric cancer. These results indicate that aberrant expression of EGR1 in gastric cancer is associated with tumor invasion and metastasis, and HPA transcription.

Small RNA interference-mediated gene silencing of heparanase abolishes the invasion, metastasis and angiogenesis of gastric cancer cells

BACKGROUND

Heparanase facilitates the invasion and metastasis of cancer cells, and is over-expressed in many kinds of malignancies. Our studies indicated that heparanase was frequently expressed in advanced gastric cancers. The aim of this study is to determine whether silencing of heparanase expression can abolish the malignant characteristics of gastric cancer cells.

METHODS

Three heparanase-specific small interfering RNA (siRNAs) were designed, synthesized, and transfected into cultured gastric cancer cell line SGC-7901. Heparanase expression was measured by RT-PCR, real-time quantitative PCR and Western blot. Cell proliferation was detected by MTT colorimetry and colony formation assay. The in vitro invasion and metastasis of cancer cells were measured by cell adhesion assay, scratch assay and matrigel invasion assay. The angiogenesis capabilities of cancer cells were measured by tube formation of endothelial cells.

RESULTS

Transfection of siRNA against 1496-1514 bp of encoding regions resulted in reduced expression of heparanase, which started at 24 hrs and lasted for 120 hrs post-transfection. The siRNA-mediated silencing of heparanase suppressed the cellular proliferation of SGC-7901 cells. In addition, the in vitro invasion and metastasis of cancer cells were attenuated after knock-down of heparanase. Moreover, transfection of heparanase-specific siRNA attenuated the in vitro angiogenesis of cancer cells in a dose-dependent manner.

CONCLUSIONS

These results demonstrated that gene silencing of heparanase can efficiently abolish the proliferation, invasion, metastasis and angiogenesis of human gastric cancer cells in vitro, suggesting that heparanase-specific siRNA is of potential values as a novel therapeutic agent for human gastric cancer.

Overexpression of matrix metalloproteinase 11 in human gastric carcinoma and its clinicopathologic significance

Matrix metalloproteinase 11 (stromelysin-3) has recently been reported to play a key role in human tumor progression and poor clinical outcome. The aim of this study was to investigate the significance of matrix metalloproteinase 11 expression in gastric cancer. Using real-time quantitative reverse-transcription polymerase chain reaction analysis and immunohistochemistry, we studied matrix metalloproteinase 11 expression levels in non-malignant gastric tissues and in gastric cancer tissues. The association between matrix metalloproteinase 11 expression levels and tumor stage and grade, as well as metastatic potential, was analyzed. Our results show that matrix metalloproteinase 11 expression was significantly higher in gastric cancer specimens compared with nonmalignant tissues at both transcriptional and protein levels, indicating its positive role in the development of gastric cancer. In addition, increased matrix metalloproteinase 11 expression levels were associated with advanced-stage and high-grade tumors, suggesting its involvement in the progression of gastric cancer. More importantly, increased matrix metalloproteinase 11 expression in gastric cancer specimens was correlated with increased expression of IGF-1, a molecule known to stimulate the proliferation, enhanced survival, and migration of cancer cells. Our results demonstrate that matrix metalloproteinase 11 is a novel factor in the development and progression of gastric cancer and suggest that matrix metalloproteinase 11 is a marker for advanced gastric cancer.

Overexpression of VCC-1 gene in human hepatocellular carcinoma cells promotes cell proliferation and invasion

Vascular endothelial growth factor-correlated chemokine 1 (VCC-1), a novel chemokine, is hypothesized to be associated with carcinogenesis. VCC-1 is expressed in hepatocellular carcinoma (HCC) cells, but its function remains unknown. To investigate the molecular effects of VCC-1 on HCC cells, the HCC cell line SMMC7721 was stably transfected with the recombinant plasmid pcDNA3.1/VCC-1. Our data demonstrated that overexpression of VCC-1 in SMMC7721 cells significantly enhanced the cellular proliferation, invasive ability, and tumor growth, when compared with both empty vector control cells and parental cells. These results strongly suggest that VCC-1 plays an important role in SMMC7721 invasion and tumor growth, and indicate that VCC-1 may serve as a potential biomarker for anti-HCC therapies.

MMP11: a novel target antigen for cancer immunotherapy

PURPOSE

Matrix metalloproteinases (MMP) are zinc-dependent endopeptidases that mediate numerous physiologic and pathologic processes, including matrix degradation, tissue remodeling, inflammation, and tumor metastasis. To develop a vaccine targeting stromal antigens expressed by cancer-associated fibroblasts, we focused on MMP11 (or stromelysin 3). MMP11 expression correlates with aggressive profile and invasiveness of different types of carcinoma.

EXPERIMENTAL DESIGN

To show the efficacy of a vaccine targeting MMP11, we constructed a series of plasmid DNA vectors expressing murine MMP11. Mice were vaccinated by i.m. injection followed by in vivo DNA electroporation. A chemically induced, MMP11-overexpressing colon cancer model was established and characterized. Antibody and T-cell responses were determined, and immunoreactive epitopes were characterized. To analyze the possible use of MMP11 as tumor-associated antigen in cancer patients, HLA-A2.1 transgenic mice (HHD) were used to identify reactive epitopes as tools to assess immunogenicity in humans.

RESULTS

Using microarray, we confirmed the overexpression of MMP11 mRNA in a large panel of human tumor samples. MMP11 vaccine induced cell mediated and antibody immune response and exerted significant antitumoral protection in mice with colon cancer in prophylactic and therapeutic settings. HHD transgenic mice were vaccinated with a plasmid encoding human MMP11, and a HLA-A2.1--restricted epitope (hMMP(237)) was identified. hMMP(237) was shown to be immunogenic in human peripheral blood mononuclear cells (PBMC) by in vitro priming.

CONCLUSION

Our study describes the identification of MMP11 as a novel broadly expressed tumor associated antigen as target candidate for cancer immunotherapy.

Cancer cells, adipocytes and matrix metalloproteinase 11: a vicious tumor progression cycle

This brief review focuses on the emerging role of matrix metalloproteinase 11 (MMP-11) in cancer progression. It has recently been shown that MMP-11 is induced in adipose tissue by cancer cells as they invade their surrounding environment. MMP-11 negatively regulates adipogenesis by reducing pre-adipocyte differentiation and reversing mature adipocyte differentiation. Adipocyte dedifferentiation in turn leads to the accumulation of nonmalignant peritumoral fibroblast-like cells, which favor cancer cell survival and tumor progression. This MMP-11-mediated bi-directional cross-talk between invading cancer cells and adjacent adipocytes/pre-adipocytes highlights the central role that MMP-11 plays during tumor desmoplasia and represents a molecular link between obesity and cancer.

Identification of matrix metalloproteinase 11 as a predictive tumor marker in serum based on gene expression profiling

PURPOSE

Prognostic markers discovery is a strategy for early diagnosis and individualization therapy for human cancer. In this study, we focus to integrate different methods to identify specific biomarker and elucidate its clinical significance.

EXPERIMENTAL DESIGN

A powerful tool named Digital Gene Expression Display online was applied to isolate differentially expressed genes correlated with gastric cancer. Matrix metalloproteinase 11 (MMP11) was selected and confirmed at both mRNA and protein level in 10 cell lines, 123 cases of tumor tissues, and 305 cases of gastric cancer serum specimen by semiquantitative PCR, immunohistochemistry staining, and ELISA techniques, respectively.

RESULTS

Our data showed that overexpression of MMP11 at mRNA and protein level was consistently detected in cell lines and primary tumors compared with matched normal tissues. Importantly, serum MMP11 levels were also significantly elevated in gastric cancer patients compared with those of the control subjects (P < 0.001), and the positive expression was well correlated with metastasis in gastric cancer patients (P = 0.009). Furthermore, we have shown that overexpression of MMP11 was associated with the malignant proliferation of AGS cells.

CONCLUSIONS

Combination of gene expression profiling and specific clinical resource is a promising approach to validate gene expression patterns associated with malignant phenotype. As a secreted protein, MMP11 may play an important role in carcinogenesis and has potential implication as a biomarker for the diagnosis and prognosis of human cancers including gastric cancer.

Identification and characterization of a novel p42.3 gene as tumor-specific and mitosis phase-dependent expression in gastric cancer

Multiple genetic alterations are attributed to gastric cancer (GC); however, only a few critical genes have been identified so far. In this study, we isolated and characterized a novel gene p42.3, represented as tumor-specific and mitosis phase-dependent expression protein in GC cell line BGC823. Our data showed that the expression of p42.3 was cell cycle-dependent in GC cell lines. Moreover, p42.3 was specifically expressed in primary GC tissues but not in the matched normal mucosa of stomach, and this gene was expressed in diverse embryonic tissues. Furthermore, significant suppression of cell proliferation and tumorigenicity were detected and G(2)/M phase arrest was observed in cell line BGC823 depleted of p42.3 expression by RNAi technique, and we confirmed the expression changes of cyclin B1 and Chk2 following the silence of p42.3. Taken together, we cloned and characterized p42.3 gene that was specifically expressed in GC tumors but not in normal gastric mucosa, and the gene was associated with M-phase regulation. Moreover, p42.3 might be involved in cell proliferation and tumorigenesis; therefore, this gene might have potential applications in the diagnosis or treatment of GC.

Identification of carboxypeptidase of glutamate like-B as a candidate suppressor in cell growth and metastasis in human hepatocellular carcinoma

PURPOSE

We have previously done large-scale cDNA transfection screening on human hepatocellular carcinoma (HCC) cells and have identified 3,806 cDNA genes that possess the ability of either stimulating or inhibiting cell growth. In this study, we characterized one of these growth suppressor genes, carboxypeptidase of glutamate like-B (CPGL-B), in HCC.

EXPERIMENTAL DESIGN

Semiquantitative reverse-transcription PCR was used to examine the expression levels of CPGL-B. The cellular localization and functions of CPGL-B were investigated by enforced expression of CPGL-B in HCC cells.

RESULTS

From our previous cDNA transfection screening, we identified a gene named CPGL and its isoform, CPGL-B. With computational analysis, CPGL was located at chromosome 18q22.3 and was a homologue of peptidase family M20. CPGL was expressed in all adult and fetal tissues, whereas its isoform, CPGL-B, lacking exons 3 and 4, was expressed in all fetal tissues but only in liver and placenta of adult tissues. In HCC, CPGL-B was frequently underexpressed (35 of 90, 38.9%) in tumorous tissues compared with the corresponding nontumorous livers. Intriguingly, the underexpression was significantly associated with the presence of venous invasion (P=0.018) and tumor microsatellite formation (P=0.004). Stable transfection of CPGL-B in SMMC7721 HCC cells showed significant inhibition in cell viability, colony formation, cell invasion, and tumor formation in nude mice. CPGL-B also down-regulated CXCR3, matrix metalloproteinase 11, and CD44s, which are involved in cell growth and cell migration.

CONCLUSIONS

These findings suggest that the frequent underexpression of CPGL-B may be associated with cell growth and metastasis of HCC.

Stromelysin-3 over-expression enhances tumourigenesis in MCF-7 and MDA-MB-231 breast cancer cell lines: involvement of the IGF-1 signalling pathway

BACKGROUND

Stromelysin-3 (ST-3) is over-expressed in the majority of human carcinomas including breast carcinoma. Due to its known effect in promoting tumour formation, but its impeding effect on metastasis, a dual role of ST-3 in tumour progression, depending on the cellular grade of dedifferentiation, was hypothesized.

METHODS

The present study was designed to investigate the influence of ST-3 in vivo and in vitro on the oestrogen-dependent, non-invasive MCF-7 breast carcinoma cell line as well as on the oestrogen-independent, invasive MDA-MB-231 breast carcinoma cell line. Therefore an orthotopic human xenograft tumour model in nude mice, as well as a 3D matrigel cell culture system, were employed.

RESULTS

Using both in vitro and in vivo techniques, we have demonstrated that over-expression of ST-3 in MCF-7 and MDA-MB-231 cells leads to both increased cell numbers and tumour volumes. This observation was dependent upon the presence of growth factors. In particular, the enhanced proliferative capacity was in MCF-7/ST-3 completely and in MDA-MB-231/ST-3 cells partially dependent on the IGF-1 signalling pathway. Microarray analysis of ST-3 over-expressing cells revealed that in addition to cell proliferation, further biological processes seemed to be affected, such as cell motility and stress response. The MAPK-pathway as well as the Wnt and PI3-kinase pathways, appear to also play a potential role. Furthermore, we have demonstrated that breast cancer cell lines of different differentiation status, as well as the non-tumourigenic cell line MCF-10A, have a comparable capability to induce endogenous ST-3 expression in fibroblasts.

CONCLUSION

These data reveal that ST-3 is capable of enhancing tumourigenesis in highly differentiated "early stage" breast cancer cell lines as well as in further progressed breast cancer cell lines that have already undergone epithelial-mesenchymal transition. We propose that ST-3 induction in tumour fibroblasts leads to the stimulation of the IGF-1R pathway in carcinoma cells, thus enhancing their proliferative capacity. In addition, further different cellular processes seem to be activated by ST-3, possibly accounting for the dual role of ST-3 in tumour progression and metastasis.

Tissue fibrosis and carcinogenesis: divergent or successive pathways dictate multiple molecular therapeutic targets for oligo decoy therapies

The extracellular matrix (ECM) is composed of several families of macromolecular components: fibrous proteins such as collagens, type I collagen (COL1), type III collagen (COL3), fibronectin, elastin, and glycoconjugates such as proteoglycans and matrix glycoproteins. Their receptors on the cell membrane, most of which in the case of the ECM belong to the integrins, which are heterodimeric proteins composed of alpha and beta chains. COL1 is the major fibrous collagen of bone, tendon, and skin; while COL3 is the more pliable collagen of organs like liver. Focus will not only be given to the regulation of synthesis of several fibrogenic parameters but also modulation of their degradation during growth factor-induced tissue fibrosis and cancer development. Evidence will be provided that certain tissues, which undergo fibrosis, also become cancerous. Why does there exist a divergency between tissues, which undergo frank fibrosis as an endpoint, and those tissues that undergo fibrosis and subsequently are susceptible to carcinogenicity; resulting from the etiological factor(s) causing the initial injury? For example, why does a polyvinyl alcohol (PVA) sponge implant become encapsulated and filled with fibrous tissue then fibrosis tissue growth stops? Why does the subcutaneous injection of a fibrogenic growth factor cause a benign growth and incisional wounding results in fibrosis and ultimately scarring? There are many examples of tissues, which undergo fibrosis as a prerequisite to carcinogenesis. Is there a cause-effect relationship? If you block tissue fibrosis in these precancerous tissues, would you block cancer formation? What are the molecular targets for blocking fibrosis and ultimately carcinogenesis? How can oligo decoys may be used to attenuate carcinogenesis and which oligo decoys specifically attenuate fibrogenesis as a prelude to carcinogenesis? What are other molecular targets for oligo decoy therapy in carcinogenesis?

Cellular prion protein promotes invasion and metastasis of gastric cancer

Cellular prion protein (PrPc) is a glycosylphosphatidylinositol (GPI) -anchored membrane protein that is highly conserved in mammalian species. PrPc has the characteristics of adhesive molecules and is thought to play a role in cell adhesion and membrane signaling. Here we investigated the possible role of PrPc in the process of invasiveness and metastasis in gastric cancers. PrPc was found to be highly expressed in metastatic gastric cancers compared to nonmetastatic ones by immunohistochemical staining. PrPc significantly promoted the adhesive, invasive, and in vivo metastatic abilities of gastric cancer cell lines SGC7901 and MKN45. PrPc also increased promoter activity and the expression of MMP11 by activating phosphorylated ErK1/2 in gastric cancer cells. MEK inhibitor PD98059 and MMP11 antibody (Ab) significantly inhibited in vitro invasive and in vivo metastatic abilities induced by PrPc. N-terminal fragment (amino acid 24-90) was suggested to be an indispensable region for signal transduction and invasion-promoting function of PrPc. Taken together, the present work revealed a novel function of PrPc that the existence of N-terminal region of PrPc could promote the invasive and metastatic abilities of gastric cancer cells at least partially through activation of MEK/ERK pathway and consequent transactivation of MMP11.

Tumour microenvironment - opinion: validating matrix metalloproteinases as drug targets and anti-targets for cancer therapy

The matrix metalloproteinases (MMPs) mediate homeostasis of the extracellular environment. They have multiple signalling activities that are commonly altered during tumorigenesis and that might serve as intervention points for anticancer drugs. However, there are many criteria to consider in validating MMPs as drug targets and for the development of MMP inhibitors. The inhibition of some MMPs could have pro-tumorigenic effects (making them anti-targets), counterbalancing the benefits of target inhibition. These effects might partially account for the failure of MMP inhibitors in clinical trials. What are the major challenges in MMP target validation and MMP-inhibitor-drug development?