Matrix metalloproteinases and gastrointestinal cancers: Impacts of dietary antioxidants

Natural Products as Regulators against Matrix Metalloproteinases for the Treatment of Cancer

Cancers are currently the major cause of mortality in the world. According to previous studies, matrix metalloproteinases (MMPs) have an impact on tumor cell proliferation, which could lead to the onset and progression of cancers. Therefore, regulating the expression and activity of MMPs, especially MMP-2 and MMP-9, could be a promising strategy to reduce the risk of cancers. Various studies have tried to investigate and understand the pathophysiology of cancers to suggest potent treatments. In this review, we summarize how natural products from marine organisms and plants, as regulators of MMP-2 and MMP-9 expression and enzymatic activity, can operate as potent anticancer agents.

Redox Biomarkers and Matrix Remodeling Molecules in Ovarian Cancer

Ovarian cancer (OC) has emerged as the leading cause of death due to gynecological malignancies among women. Oxidative stress and metalloproteinases (MMPs) have been shown to influence signaling pathways and afflict the progression of carcinogenesis. Therefore, the assessment of matrix-remodeling and oxidative stress intensity can determine the degree of cellular injury and often the severity of redox-mediated chemoresistance. The study group comprised 27 patients with serous OC of which 18% were classified as Federation of Gynecology and Obstetrics (FIGO) stages I/II, while the rest were diagnosed grades III/IV. The control group comprised of 15 ovarian tissue samples. The results were compared with genetic data from The Cancer Genome Atlas. Nitro-oxidative stress, inflammation and apoptosis biomarkers were measured colorimetrically/fluorometrically or via real-time PCR in the primary ovarian tumor and healthy tissue. Stratification of patients according to FIGO stages revealed that high-grade carcinoma exhibited substantial alterations in redox balance, including the accumulation of protein glycoxidation and lipid peroxidation products. TCGA data demonstrated only limited prognostic usefulness of the studied genes. In conclusion, high-grade serous OC is associated with enhanced tissue oxidative/nitrosative stress and macromolecule damage that could not be overridden by the simultaneously augmented measures of antioxidant defense. Therefore, it can be assumed that tumor cells acquire adaptive mechanisms that enable them to withstand the potential toxic effects of elevated reactive oxygen species.

Tumor Targeting via siRNA-COG3 to Suppress Tumor Progression in Mice and Inhibit Cancer Metastasis and Angiogenesis in Ovarian Cancer Cell Lines

BACKGROUND

The COG complex is implicated in the tethering of retrograde intra-Golgi vesicles, which involves vesicular tethering and SNAREs. SNARE complexes mediate the invasion and metastasis of cancer cells through MMPs which activate growth factors for ECM fragments by binding to integrin receptors. Increasing MMPs is in line with YKL40 since YKL40 is linked to promoting angiogenesis through VEGF and can increase ovarian cancer (OC) resistance to chemotropic and cell migration.

OBJECTIVE

The aim of this study is an assessment of siRNA-COG3 on proliferation, invasion, and apoptosis of OC cells. In addition, siRNA-COG3 may prevent the growth of OC cancer in mice with tumors.

METHODS

Primary OC cell lines will be treated with siRNA-COG3 to assay YKL40 and identified angiogenesis by Tube-like structure formation in HOMECs. The Golgi morphology was analyzed using Immunofluorescence microscopy. Furthermore, the effects of siRNA-COG3 on the proliferation and apoptosis of cells were evaluated using MTT and TUNEL assays. Clones of the HOSEpiC OC cell line were subcutaneously implanted in FVB/N mice. Mice were treated after two weeks of injection of cells using siRNA-COG3. Tumor development suppression was detected by D-luciferin. RT-PCR and western blotting analyses were applied to determine COG3, MT1- MMP, SNAP23, and YKL40 expression to investigate the effects of COG3 gene knockdown.

RESULTS

siRNA-COG3 exhibited a substantial effect in suppressing tumor growth in mice. It dramatically reduced OC cell proliferation and triggered apoptosis (all p < 0.01). Inhibition of COG3, YKL-40, and MT1-MPP led to suppression of angiogenesis and reduction of microvessel density through SNAP23 in OC cells.

CONCLUSION

Overall, by knockdown of the COG3 gene, MT1-MMP and YKL40 were dropped, leading to suppressed angiogenesis along with decreasing migration and proliferation. SiRNACOG3 may be an ideal agent to consider for clinical trial assessment therapy for OC, especially when an antiangiogenic SNAR-pathway targeting drug.

Dietary total antioxidant capacity is associated with lower disease severity and inflammatory and oxidative stress biomarkers in patients with knee osteoarthritis

BACKGROUND

This study was designed to evaluate the association between dietary total antioxidant capacity and clinical and biochemical variables in patients with osteoarthritis.

METHODS

This cross-sectional study was conducted among 160 patients with mild-to-moderate knee osteoarthritis. The Likert version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC Index) was used to assess the severity of clinical symptoms in patients with knee osteoarthritis. The secondary outcomes included inflammatory and oxidative stress biomarkers. The participants' usual diets were assessed using a food frequency questionnaire (FFQ), and the dietary total antioxidant capacity (TAC) was calculated based on the ferric reducing antioxidant power method. Additionally, clinical and biochemical variables were evaluated using standard methods.

RESULTS

The mean age of the participants was 57.2 ± 8.1 years, and 55.6% of them were females. The dietary TAC scores in this study ranged from 3.67 to 24.72, with a mean of 12.05 ± 5.3. We found a significant inverse trend between the dietary TAC score and the total Western Ontario and McMaster Universities Osteoarthritis (WOMAC) score (P = 0.001), as well as the WOMAC stiffness (P = 0.008) and WOMAC physical function scores (P = 0.001). Furthermore, dietary TAC was inversely associated with serum concentrations of interleukin-6 (IL-6) (β = - 0.18, P = 0.020), tumor necrosis factor-α (TNF-α) (β = - 0.67, P < 0.001), matrix metalloproteinase-1 (MMP-1) (β = - 0.33, P < 0.001), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) (β = - 0.22, P = 0.005) levels.

CONCLUSION

The results of this study demonstrate an inverse association between dietary total antioxidant capacity and clinical and biochemical variables in patients with osteoarthritis.

Induction of MMP-3 and MMP-9 expression during Helicobacter pylori infection via MAPK signaling pathways

BACKGROUND AND AIMS

Helicobacter pylori (H. pylori)-induced gastric pathology involves remodeling of extracellular matrix mediated by aberrant activity of matrix metalloproteinases (MMPs). We have previously shown that in vitro H. pylori infection leads to MMP-3 and MMP-9 overexpression, associated with phosphorylation of bacterial oncoprotein CagA. We extended these findings in an in vivo model of H. pylori infection and further assessed the involvement of MAPK pathways in MMP expression.

MATERIALS AND METHODS

C57BL/6 mice were infected with H. pylori strains HPARE, HPARE ΔCagA, and SS1, for 6 and 9 months. Transcriptional expression of Mmp-3 and Mmp-9 was evaluated via qPCR while respective protein levels in the gastric mucosa were determined immunohistochemically. Epithelial cell lines AGS and GES-1 were infected with H. pylori strain P12 in the presence of chemical inhibitors of JNK, ERK1/2, and p38 pathways, for 24 h. mRNA and protein expression of MMP-3 and MMP-9 were determined via qPCR and Western blot, respectively.

RESULTS

We observed transcriptional activation of Mmp-3 and Mmp-9 as well as aberrant MMP-3 and MMP-9 protein expression in murine gastric tissue following H. pylori infection. CagA expression was associated with MMP upregulation, particularly during the early time points of infection. We found that inhibition of ERK1/2 resulted in reduced mRNA and protein expression of MMP-3 and MMP-9 during H. pylori infection, in both cell lines. Expressed protein levels of both MMPs were also found reduced in the presence of JNK pathway inhibitors in both cell lines. However, p38 inhibition resulted in a more complex effect, probably attributed to the accumulation of phospho-p38 and increased phospho-ERK1/2 activity due to crosstalk between MAPK pathways.

CONCLUSIONS

H. pylori colonization leads to the upregulation of MMP-3 and MMP-9 in vivo, which primarily involves ERK1/2 and JNK pathways. Therefore, their inhibition may potentially offer a protective effect against gastric carcinogenesis and metastasis.

The Anti-Helicobacter pylori effects of Limosilactobacillus reuteri strain 2892 isolated from Camel milk in C57BL/6 mice

Helicobacter pylori infection (H. pylori) is associated with chronic gastritis, peptic ulcers, and gastric cancer. The present study provides information on the protective effects of Limosilactobacillus reuteri strain 2892 (L. reuteri 2892) isolated from camel's milk against H. pylori-induced gastritis in the stomach tissue of animal models. Animal assays revealed that L. reuteri 2892 pretreatment significantly downregulated the virulence factor cagA gene expression. It upregulated the expression level of tight junction molecules [zona occludens (ZO-1), claudin-4] and suppressed metalloproteinase (MMP)-2 and MMP-9 expressions. L. reuteri 2892 exhibited immunomodulatory effects on cytokine profile, as it reduced the serum concentrations of pro-inflammatory cytokines interleukin (IL)-6, IL-1β, and INF-γ and increased the anti-inflammatory cytokine, IL-10. In addition, L. reuteri 2892 showed anti-oxidative stress activity by regulating the levels of oxidative stress-associated markers [superoxide dismutase (SOD) and malondialdehyde (MDA)]. Our findings suggest that L. reuteri 2892 attenuates H. pylori-induced gastritis.

The comparative evaluation of the effects of quercetin, α-tocopherol, and chlorhexidine dentin pretreatments on the durability of universal adhesives

OBJECTIVE

The aim of this study was to evaluate and compare the effects of chlorhexidine, quercetin, and α-tocopherol on the shear bond strength of universal adhesives in the short (24h) and long term (6 months).

MATERIAL AND METHODS

Ninety-six extracted sound molars were collected and divided randomly into four groups: control (no treatment), 2% chlorhexidine, 10% α-tocopherol, and 1% quercetin. The solutions were prepared and applied to the teeth for 60 s, followed by application of All-Bond universal adhesive and composite build-up. Half of the specimens in each group (n = 12) were tested for shear bond strength (SBS) after 24 h of storage and the other half were kept in distilled water for 6 months and then tested for shear bond strength. The shear bond strength test was performed and the failure modes were determined using a stereomicroscope. The data were analyzed using two-way analysis of variance and Tukey's post hoc tests with p ˂ .05 as the significance level.

RESULTS

The results of the two-way analysis of variance test showed that there was no significant difference in immediate SBS, and after 6 months, α-tocopherol had the lowest SBS in comparison to the control and CHX subgroups (p < .05). The t-test showed that the shear bond strength in the α-tocopherol and quercetin groups was significantly decreased after 6 months.

CONCLUSION

It can be concluded that the solutions used in this study had no adverse effect on immediate SBS. After 6 months, the CHX could preserve SBS in comparison to other groups.

Cancer Stem Cells in Tumor Microenvironment of Adenocarcinoma of the Stomach, Colon, and Rectum

Gastrointestinal adenocarcinomas are one of the world's deadliest cancers. Cancer stem cells and the tissue microenvironment are highly regulated by cell and molecular mechanisms. Cancer stem cells are essential for maintenance and progression and are associated with resistance to conventional treatments. This article reviews the current knowledge of the role of the microenvironment during the primary establishment of gastrointestinal adenocarcinomas in the stomach, colon, and rectum and its relationship with cancer stem cells. We also describe novel developments in cancer therapeutics, such as targeted therapy, and discuss the advantages and disadvantages of different treatments for improving gastrointestinal cancer prognosis.

The effect of opine on matrix metalloproteinase expression in mice with breast cancer

Regarding the anti-inflammatory and anti-tumour effects of arginine and its derivatives, this study evaluates matrix metalloproteinase (MMPs) expression in an animal model of breast cancer following administration of octopine. In this study, 40 animals of Balb/C mice were divided into 5 groups: the healthy control, the cancer control, the cancer group receiving 50 mg of octopine, the cancer group receiving 100 mg of octopine and the cancer group receiving 150 mg of octopine for 3 weeks. 4T1 cell line was used to induce cancer. Biopsy specimens were enrolled from mice and MMP-1, MMP-3 and MMP-9 gene expression evaluated using real-time PCR, while these protein amounts were measured using immunohistochemistry and ELISA methods. Data were analysed using one-way ANOVA, Kruskal-Wallis and Mann-Whitney U tests (p < .05). The results showed that 100 mg octopine consumption had significant decreasing effect on MMP-9 expression (p = .02) in the treatment group compared with cancerous non-treated mice. Furthermore, results from immunohistochemistry and ELISA confirmed this effect, the protein amount of MMP-9 was significantly decreased in group treating with 100 mg octopine (.005). The use of octopine has a beneficial effect on reducing MMP-9 in mice breast cancer.

Redox regulation of DUBs and its therapeutic implications in cancer

Reactive oxygen species (ROS) act as a double-edged sword in cancer, where low levels of ROS are beneficial but excessive accumulation leads to cancer progression. Elevated levels of ROS in cancer are counteracted by the antioxidant defense system. An imbalance between ROS generation and the antioxidant system alters gene expression and cellular signaling, leading to cancer progression or death. Post-translational modifications, such as ubiquitination, phosphorylation, and SUMOylation, play a critical role in the maintenance of ROS homeostasis by controlling ROS production and clearance. Recent evidence suggests that deubiquitinating enzymes (DUBs)-mediated ubiquitin removal from substrates is regulated by ROS. ROS-mediated oxidation of the catalytic cysteine (Cys) of DUBs, leading to their reversible inactivation, has emerged as a key mechanism regulating DUB-controlled cellular events. A better understanding of the mechanism by which DUBs are susceptible to ROS and exploring the ways to utilize ROS to pharmacologically modulate DUB-mediated signaling pathways might provide new insight for anticancer therapeutics. This review assesses the recent findings regarding ROS-mediated signaling in cancers, emphasizes DUB regulation by oxidation, highlights the relevant recent findings, and proposes directions of future research based on the ROS-induced modifications of DUB activity.

Mucin 1 as a Molecular Target of a Novel Diisoquinoline Derivative Combined with Anti-MUC1 Antibody in AGS Gastric Cancer Cells

BACKGROUND

The aim of the study was to examine the molecular mechanism of the anticancer action of a monoclonal antibody against MUC1 and a diisoquinoline derivative (OM-86II) in human gastric cancer cells.

METHODS

The cell viability was measured by the MTT assay. The disruption of mitochondrial membrane potential and activity of caspase-8 and caspase-9 was performed by flow cytometry. Fluorescent microscopy was used to confirm the proapoptotic effect of compounds. LC3A, LC3B and Beclin-1 concentrations were analyzed to check the influence of the compounds on induction of autophagy. ELISA assessments were performed to measure the concentration of mTOR, sICAM1, MMP-2, MMP-9 and pro-apoptotic Bax.

RESULTS

The anti-MUC1 antibody with the diisoquinoline derivative (OM-86II) significantly reduced gastric cancer cells' viability. This was accompanied by an increase in caspase-8 and caspase-9 activity as well as high concentrations of pro-apoptotic Bax. We also proved that the anti-MUC1 antibody with OM-86II decreased the concentrations of MMP-9, sICAM1 and mTOR in gastric cancer cells. After 48 h of incubation with such a combination, we observed higher levels of the crucial component of autophagosomes (LC3) and Beclin-1.

CONCLUSIONS

Our study proved that the anti-MUC1 antibody sensitizes human gastric cancer cells to the novel diisoquinoline derivative (OM-86II) via induction of apoptosis and autophagy, and inhibition of selected proteins such as mTOR, sICAM1 and MMP-9.

Bacteriophage manipulation of the microbiome associated with tumour microenvironments-can this improve cancer therapeutic response?

Some cancer treatment failures have been attributed to the tumour microbiota, with implications that microbiota manipulation may improve treatment efficacy. While antibiotics have been used to control bacterial growth, their dysbiotic effects on the microbiome, failure to penetrate biofilms and decreased efficacy due to increasing antimicrobial resistance by bacteria, suggest alternatives are needed. Bacteriophages may provide a precise means for targeting oncobacteria whose relative abundance is increased in tumour tissue microbiomes. Fusobacterium, Streptococcus, Peptostreptococcus, Prevotella, Parvimonas, and Treponema species are prevalent in tumour tissue microbiomes of some cancers. They may promote cancer growth by dampening immunity, stimulating release of proinflammatory cytokines, and directly interacting with cancer cells to stimulate proliferation. Lytic bacteriophages against some of these oncobacteria have been isolated and characterised. The search continues for others. The possibility exists for their testing as adjuncts to complement existing therapies. In this review, we highlight the role of oncobacteria, specifically those whose relative abundance in the intra-tumour microbiome is increased, and discuss the potential for bacteriophages against these micro-organisms to augment existing cancer therapies. The capacity for bacteriophages to modulate immunity and kill specific bacteria makes them suitable candidates to manipulate the tumour microbiome and negate the effects of these oncobacteria.

Untargeted Metabolomics for the Diagnosis of Exocrine Pancreatic Insufficiency in Chronic Pancreatitis

Background and Objectives: The clinical manifestations and course of chronic pancreatitis (CP) are often nonspecific and variable, hampering diagnosis of the risk of exocrine pancreatic insufficiency (EPI). Development of new, reproducible, and non-invasive methods to diagnose EPI is therefore a major priority. The objective of this metabolomic study was to identify novel biomarkers associated with EPI. Materials and Methods: We analyzed 53 samples from patients with CP, 32 with and 21 without EPI, using an untargeted metabolomics workflow based on hydrophilic interaction chromatography coupled to high-resolution mass spectrometry. Principal component and partial least squares-discriminant analyses showed significant between-group differentiation, and univariate and multivariate analyses identified potential candidate metabolites that significantly differed between samples from CP patients with EPI and those without EPI. Results: Excellent results were obtained using a six-metabolic panel to diagnose the presence of EPI in CP patients (area under the ROC curve = 0.785). Conclusions: This study confirms the usefulness of metabolomics in this disease setting, allowing the identification of novel biomarkers to differentiate between the presence and absence of EPI in CP patients.

The complex interplay of gut microbiota with the five most common cancer types: From carcinogenesis to therapeutics to prognoses

The association between human gut microbiota and cancers has been an evolving field of biomedical research in recent years. The gut microbiota is composed of the microorganisms residing in the gastrointestinal system that interact with the host to regulate behaviours and biochemical processes within the gut. This symbiotic physiological interaction between the gut and the microbiota plays a significant role in the modulation of gut homeostasis, in which perturbations to the microbiota, also known as dysbiosis can lead to the onset of diseases, including cancer. In this review, we analysed the current literature to understand the role of gut microbiota in the five most prevalent cancer types, namely colon (colorectal), lung, breast, prostate, and stomach cancers. Recent studies have observed the immunomodulatory and anti-tumoural effects of gut microbiota in cancers. Furthermore, gut microbial dysbiosis can induce the release of toxic metabolites and exhibit pro-tumoural effects in the host. The gut microbiota was observed to have clinical implications in each cancer type in addition to regulating the efficacy of standard chemotherapy and natural anticancer agents. However, further research is warranted to understand the complex role of gut microbiota in the prevention, diagnosis, treatment, and prognoses of cancer.

Isolation and characterization of ergosterol from Monascus anka for anti-lipid peroxidation properties

Unbalanced lipid peroxidation damages the human body, and is associated with the formation of tumors, infections, inflammations, autoimmune diseases, and cardiovascular and cerebrovascular diseases. However, food and drugs that contain anti-lipid peroxidation active substances, can help to protect against these negative health impacts. We observed lipid peroxidation inhibition in the metabolites of fermented Monascus anka, in media with Dendrobium nobile Lindl. The anti-lipid peroxidation ability of the extracts was strongest in ethyl acetate, so this was selected for further purifications. A crystal with strong antioxidant properties was obtained by column chromatography. Based on its spectroscopic analysis by Electron Bombardment Ion Source and Mass Spectrometry (EI-MS), ¹H-Nuclear Magnetic Resonance (¹H-NMR), and ¹³C-Nuclear Magnetic Resonance (¹³C-NMR), the isolated crystal was identified as ergosterol. The inhibition rates of the lipid peroxide due to the ergosterol were 57.42%, at 2μg/mL in vitro. Simultaneously, the survival rates of the damaged cells treated with 0.3mmol/L H₂O₂ were significantly improved with the ergosterol, up to 43.88% (200μg/mL) and 46.64% (400μg/mL), compared to 36.47% for the injured cells. The survival rate of the cells was 78.32% (400μg/mL), with ergosterol as a prevention. Cell injury can increase the level of intracellular ROS, but its levels in the damaged cells were reduced after the ergosterol treatments, and the reduction increased with the increasing concentrations. A 400μg/mL concentration resulted in the lowest fluorescence intensity; 33421.11 AU below the normal level. Ergosterol significantly reduced the ROS levels, to reduce the cell damage. Ergosterol from Monascus anka was thus found to have strong anti-lipid peroxidation and antioxidant capabilities, and the ability to protect and repair damaged cells. It may consequently serve as a potential natural antioxidant and will play an important role in human anti-lipid peroxide.

TNM staging for GIT cancers is correlated with the level of MMPs and TGF-β1

Gastrointestinal (GIT) cancers represent the third common cancers worldwide, characterized by rapid progression and higher mortality rate. Matrix metalloproteinases (MMPs) play an important role in cancer metastases. The present study was conducted to estimate and evaluate the role of MMP-7, -9, -10 and -12 and TGF β1 along with conventional biomarkers (CEA and CA19-9) in gastric (GC), pancreatic (PC) and colorectal cancer (CRC) staging system according to tumor size (T), included lymph node (N) and metastasis (M). Seventy-five patients were divided into GC group (n = 25), PC group (n = 25), CRC group (n = 25) and twenty-five healthy subjects (control group). Serum levels of MMP-7, -10 and -12 were assayed simultaneously using luminex multiplex technique. Also, MMP-9, TGF-β1, CA19-9 and CEA were determined by ELISA. MMP-7,-9,-10, -12, TGF-β1 and CEA levels were significantly (p < 0.001) higher in GIT cancer groups compared with control. CA19-9 was significantly (p < 0.001) higher in PC and CRC groups compared with control. MMP-9 was positively correlated with TNM staging in PC patients. MMP-12 was negatively correlated with T in PC and positively correlated with M in CRC group. CA 19-9 was positively correlated with M grade in CRC. Depending on the estimated cutoff values of area under receiver curve; CA19-9 and MMP-7 were excellent diagnostic markers in PC, CEA and MMP-7 were excellent in CRC, and MMP-7 and MMP-9 were excellent in GC. Our findings indicated the clinical utility of MMPs in diagnosis and TNM staging of GIT cancers along with CEA and CA19-9.

C. perfringens challenge reduces matrix metalloproteinase activity in the jejunal mucosa of Eimeria-infected broiler chickens

Matrix metalloproteinases (MMPs) play an important role in intestinal extracellular matrix homeostasis. An overexpression of MMPs results in tissue destruction and local inflammation and has been associated with multiple inflammatory diseases. These host proteases might also be important in tissue damage caused by infectious agents, such as in intestinal damage in Clostridium perfringens-induced avian necrotic enteritis (NE). The aim of the present study was to elucidate the effect of a C. perfringens infection on the MMP activity in the small intestine of birds with a pre-disposing coccidial infection to obtain a more thorough understanding of the pathogenesis of NE. For this purpose, the gelatinolytic activity present in jejunal tissue of Eimeria infected birds which were challenged with either a pathogenic C. perfringens type G strain or a commensal C. perfringens type A strain was analyzed using substrate zymography. The results show that infection of broilers with Eimeria and different C. perfringens strains, independent of their pathogenicity, decreases the expression of a 40-45 kDa host collagenase in the jejunum, as compared to the expression in Eimeria-infected control birds. It was also shown that the expression of 2 MMPs with molecular weights of approximately 50-60 and 60-70 kDa was significantly lower in necrotic tissue as compared to the activity in macroscopically healthy tissue adjacent to the lesion. These results indicate that host collagenases are not elicited by the C. perfringens infection for permeabilizing the host mucosa to allow penetration of the NetB toxin in Eimeria infected broilers.

The lysine derivative aminoadipic acid, a biomarker of protein oxidation and diabetes-risk, induces production of reactive oxygen species and impairs trypsin secretion in mouse pancreatic acinar cells

We have examined the effects of α-aminoadipic acid, an oxidized derivative from the amino acid lysine, on the physiology of mouse pancreatic acinar cells. Changes in intracellular free-Ca²⁺ concentration, the generation of reactive oxygen species, the levels of carbonyls and thiobarbituric-reactive substances, cellular metabolic activity and trypsin secretion were studied. Stimulation of mouse pancreatic cells with cholecystokinin (1 nM) evoked a transient increase in [Ca²⁺]_i. In the presence of α-amoniadipic acid increases in [Ca²⁺]_i were observed. In the presence of the compound, cholecystokinin induced a Ca²⁺ response that was smaller compared with that observed when cholecystokinin was applied alone. Stimulation of cells with cholecystokinin in the absence of Ca²⁺ in the extracellular medium abolished further mobilization of Ca²⁺ by α-aminoadipic acid. In addition, potential pro-oxidant conditions, reflected as increases in ROS generation, oxidation of proteins and lipids, were noted in the presence of α-aminoadipic acid. Finally, the compound impaired trypsin secretion induced by the secretagogue cholecystokinin. We conclude that the oxidized derivative from the amino acid lysine induces pro-oxidative conditions and the impairment of enzyme secretion in pancreatic acinar cells. α-aminoadipic acid thus creates a situation that could potentially lead to disorders in the physiology of the pancreas.

Secreted Phosphoprotein 1 (SPP1) and Fibronectin 1 (FN1) Are Associated with Progression and Prognosis of Esophageal Cancer as Identified by Integrated Expression Profiles Analysis

Background

Esophageal cancer is a malignant tumor with a complex pathogenesis and a poor 5-year survival rate, which encourages researchers to explore its molecular mechanisms deeper to improve the prognosis.

Material/Methods

DEGs were from 4 Gene Expression Omnibus (GEO) databases (GSE92396, GSE20347, GSE23400, and GSE45168) including 87 esophageal tumor samples and 84 normal samples. We performed Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Protein-Protein interaction (PPI) analysis, and GeneMANIA to identify the DEGs. Gene set enrichment analysis (GSEA) and Kaplan-Meier survival analyses were performed.

Results

There was an overlapping subset consisting of 120 DEGs that was present in all esophageal tumor samples. The DEGs were enriched in extracellular matrix (ECM)-receptor interaction, as well as focal adhesion and transcriptional mis-regulation in cancer. The 2 most crucial regulatory pathways in esophageal cancer were the amebiasis pathway and the PI3K-Akt signaling pathway. Secreted phosphoprotein 1 (SPP1) and fibronectin 1 (FN1) were selected and verified in an independent cohort and samples using the TCGA and GTEx projects. Gene set enrichment analysis (GSEA) showed that proteasome and nucleotide excision repair were 2 most differentially enriched pathways in the SPP1 high-expression phenotype, and ECM-receptor interaction and focal adhesion in FN1 high-expression phenotype. Kaplan-Meier survival analysis showed that SPP1 and FN1 were significantly positively related to overall survival and had the potential to predict patient relapse.

Conclusions

Our analysis is the first to show that SPP1 and FN1 might work as biological markers of progression and prognosis in esophageal carcinoma (ESCA).

Triumph and tumult of matrix metalloproteinases and their crosstalk with eicosanoids in cancer

Cancer development and metastasis are associated to perturbation in metabolic functions of tumor cells and surrounding inflammatory and stromal cell responses. Eicosanoids and lipid mediators, in this regard, attract potential attention during cancer development. Eicosanoids, which include prostaglandin, prostacyclin, thromboxane, and leukotriene, are synthesized from arachidonic acid when cells are stimulated by stress, cytokines, or other growth factors. However, the underlying mechanism of eicosanoids in cancer development, specially their interactions with proto-oncogene factors in tumor microenvironment, remain unexplored. On the other hand, matrix metalloproteinases (MMPs) are a group of zinc-dependent endopeptidases which are involved in degradation of different extracellular matrix (ECM) proteins. MMPs are associated with different physiological responses, including embryogenesis, vasculogenesis, and cellular remodeling, as well as different disease pathogenesis. Induced MMP responses are especially associated with cancer metastasis and secondary tumor development through proteolytic cleavage of several ECM and non-ECM proteins. Although both eicosanoids and MMPs are involved with cancer progression and metastasis, the interrelation between these two molecules are less explored. The present review discusses relevant studies that connect eicosanoids and MMPs and highlight the crosstalk between them offering novel therapeutic approach in cancer treatment.

The Effect of Oral Administration of PUFAs on the Matrix Metalloproteinase Expression in Gastric Adenocarcinoma Patients Undergoing Chemotherapy

OBJECTIVE

Gastric cancer is the third-leading cause of cancer-related mortality and the fifth most common cancer globally. Polyunsaturated fatty acids (PUFAs) are considered as functional ingredients that improve the efficacy of chemotherapeutic drugs. The aim of this study is to investigate the effect of PUFAs administration on matrix metalloproteinases (MMPs).

METHODS

This study was designed as a randomized, double-blind trial. Thirty-four newly diagnosed patients with gastric cancer were randomly divided into two groups: control group (n = 17) and case group (n =17). Both groups received the same dose (75 mg/m²) of cisplatin. Control group received cisplatin plus placebo and the case group received cisplatin plus PUFAs [3600 mg/day, for three courses (each course included 3 weeks)]. The mRNA and protein expression of MMPs determined by real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC), respectively.

RESULTS

The relative gene expression of MMP-1 and MMP-9 was significantly lower in case group than control. The protein expression of MMP-1 and MMP-9 was significantly lower in case group than control.

CONCLUSION

According to the results of this study, PUFAs reduced the expression of MMPs in gastric cancer cells. It seems that PUFAs may have an inhibitory effect on invasion and metastasis of gastric cancer cells.

Knockdown of MON1B Exerts Anti-Tumor Effects in Colon Cancer In Vitro

Background

Colon cancer is one of the most common cancers in the world. We performed the present study to determine the molecular mechanism of MON1B in colon cancer cells.

Material/Methods

Colon cancer tissues and adjacent normal tissues were collected from 34 colon cancer patients. MON1B-silenced LoVo colon cancer cells were constructed. RT-qPCR and Western blot analysis were used to detect mRNA and protein levels, respectively, of colon cancer tissues and cells. Cell counting kit-8 (CCK-8), wound healing, and Transwell assays were used to detect viability, migration, and invasion, respectively, of colon cancer cells.

Results

The mRNA and protein levels of MON1B were higher in colon cancer tissues and human colon cancer cell lines (HT-29, SW480, COLO205, LoVo). Cell proliferation, migration, and invasion abilities were all inhibited when MON1B was silenced in LoVo colon cancer cells. Both the mRNA and protein levels of tissue inhibitor of metalloproteinase (TIMP)-2 and iκB were increased, while that of matrix metalloproteinases (MMP)-2, MMP-9, metastasis-associated genes (MTA)-1, nuclear factor-kappa B (NF-κB), and chemokine receptor type (CXCR)-4 was decreased when MON1B was silenced.

Conclusions

MON1B interference exerted anti-tumor effect in colon cancer in vitro.

Expression analysis and clinical significance of eIF4E, VEGF-C, E-cadherin and MMP-2 in colorectal adenocarcinoma

The underlying mechanisms of colorectal carcinoma (CRC) metastasis remain to be elucidated. The aim of this study is to investigate clinical significance and the expression of eIF4E, VEGF-C, MMP-2, and E-cadherin in the CRC metastasis. We investigated their expressions in 108 patients, analyzed the relationships between their expressions in CRC and evaluated the relationships between their expressions and clinical pathogenic parameters. Furthermore, their roles in patient survival and in CRC metastasis were also investigated. We found that eIF4E, VEGF-C and MMP-2 were up-regulated in CRC, and their expression frequencies (EFs) were higher in cancerous tissues than in adjacent normal tissues. The EF of E-cadherin is lower in cancerous tissues than in adjacent normal tissues. Totally, their EFs were not associated with sex and age of patient, however, their EFs were associated with tumor differentiation, the depth of invasion, lymph node metastasis and tumor stages. Furthermore, eIF4E, VEGF-C, and MMP-2 shortened and E-cadherin prolonged survival in patient-derived CRC xenografts. Similarly, eIF4E, VEGF-C, and MMP-2 promoted and E-cadherin suppressed the lung metastasis of CRC cells. In addition, knockdown of eIF4E inhibited migration of CRC cells, downregulated VEGF-C, MMP-2 and upregulated E-cadherin. In conclusion, eIF4E promoted CRC metastasis via up-regulating the expression of VEGF-C, MMP-2 and suppressing E-cadherin.

Treponema denticola chymotrypsin-like proteinase may contribute to orodigestive carcinogenesis through immunomodulation

Background:

Periodontal pathogens have been linked to oral and gastrointestinal (orodigestive) carcinogenesis. However, the exact mechanisms remain unknown. Treponema denticola (Td) is associated with severe periodontitis, a chronic inflammatory disease leading to tooth loss. The anaerobic spirochete Td is an invasive bacteria due to its major virulence factor chymotrypsin-like proteinase. Here we aimed to investigate the presence of Td chymotrypsin-like proteinase (Td-CTLP) in major orodigestive tumours and to elucidate potential mechanisms for Td to contribute to carcinogenesis.

Methods:

The presence of Td-CTLP within orodigestive tumour tissues was examined using immunohistochemistry. Oral, tonsillar, and oesophageal squamous cell carcinomas, alongside gastric, pancreatic, and colon adenocarcinomas were stained with a Td-CTLP-specific antibody. Gingival tissue from periodontitis patients served as positive controls. SDS–PAGE and immunoblot were used to analyse the immumodulatory activity of Td-CTLP in vitro.

Results:

Td-CTLP was present in majority of orodigestive tumour samples. Td-CTLP was found to convert pro MMP-8 and -9 into their active forms. In addition, Td-CTLP was able to degrade the proteinase inhibitors TIMP-1, TIMP-2, and α-1-antichymotrypsin, as well as complement C1q.

Conclusions:

Because of its presence within tumours and regulatory activity on proteins critical for the regulation of tumour microenvironment and inflammation, the Td-CTLP may contribute to orodigestive carcinogenesis.

The extracellular matrix of the gastrointestinal tract: a regenerative medicine platform

The synthesis and secretion of components that constitute the extracellular matrix (ECM) by resident cell types occur at the earliest stages of embryonic development, and continue throughout life in both healthy and diseased physiological states. The ECM consists of a complex mixture of insoluble and soluble functional components that are arranged in a tissue-specific 3D ultrastructure, and it regulates numerous biological processes, including angiogenesis, innervation and stem cell differentiation. Owing to its composition and influence on embryonic development, as well as cellular and organ homeostasis, the ECM is an ideal therapeutic substrate for the repair of damaged or diseased tissues. Biologic scaffold materials that are composed of ECM have been used in various surgical and tissue-engineering applications. The gastrointestinal (GI) tract presents distinct challenges, such as diverse pH conditions and the requirement for motility and nutrient absorption. Despite these challenges, the use of homologous and heterologous ECM bioscaffolds for the focal or segmental reconstruction and regeneration of GI tissue has shown promise in early preclinical and clinical studies. This Review discusses the importance of tissue-specific ECM bioscaffolds and highlights the major advances that have been made in regenerative medicine strategies for the reconstruction of functional GI tissues.

The constitutive protease release by primary human acute myeloid leukemia cells

INTRODUCTION

Acute myeloid leukemia (AML) cells show constitutive release of matrix metalloproteases and their inhibitors. We now investigated this constitutive release of protease/protease regulators associated with carcinogenesis (ADAM12, uPA, cystatin B), angiogenesis (serpin E1, uPA, CD147), cancer cell migration (uPA, cystatin C), coagulation (ADAM TS13, serpin C1), inflammation (fetuin A, caspase 1, cystatin C), monocytic differentiation (CFD) or regulation of hematopoiesis (neutrophil elastase).

METHODS

AML blasts from 79 consecutive patients were cultured in serum-free medium and mediator levels determined in culture supernatants.

RESULTS

Detectable release of serpin C1 and E1, cystatin B and C, CD147 and uPA was seen for most patients. These mediators together with fetuin A, caspase 1, and CFD were included in a hierarchical clustering analysis and three patient subsets were identified (high, intermediate, and low release). High levels were associated with monocytic differentiation. Global gene expression analyses showed increased levels of several zinc finger proteins for low-release patients and high expression of several cell surface molecules, ATPases, and calcium-binding proteins for high-release patients. Constitutive release of several mediators was also seen for normal hematopoietic cells and mesenchymal stem cells. In cocultures of the latter and AML blasts, the release level for most mediators was altered to resemble the levels of the mesenchymal cells cultured alone.

CONCLUSION

Differences in constitutive release of protease/protease regulators are a part of the disease heterogeneity in AML.

Dietary Antioxidants: Potential Anticancer Agents

There are several extrinsic and intrinsic factors involving reactive oxygen species that play critical roles in tumor development and progression by inducing DNA mutations, genomic instability, and aberrant pro-tumorigenic signaling. There are various essential micronutrients including minerals and vitamins in the diet, which play pivotal roles in maintaining and reinforcing antioxidant performance, affecting the complex network of genes (nutrigenomic approach) and encoding proteins for carcinogenesis. A lot of these antioxidant agents are available as dietary supplements and are predominant worldwide. However, the best antioxidant micronutrient (or a combination of micronutrients) for reducing cancer risks is unknown. The purpose of this review is to survey the literature on modern biological theories of cancer and the roles of dietary antioxidants in cancer. The roles and functions of antioxidant micronutrients, such as vitamin C (ascorbate), vitamin E (alpha-tocopherol), selenium, and vitamin A, provided through diet for the prevention of cancer are discussed in the present work.

Attenuation of Helicobacter pylori-induced gastric inflammation by prior cag- strain (AM1) infection in C57BL/6 mice

BACKGROUND

Helicobacter pylori, colonize in stomach of ~50% of the world population. cag pathogenicity Island of H. pylori is one of the important virulent factors that attributed to gastric inflammation. Coinfection with H. pylori strain with different genetic makeup alters the degree of pathogenicity and susceptibility towards antibiotics. The present study investigates host immunomodulatory effects of H. pylori infection by both cag⁺ strain (SS1) and cag^- strain (AM1). C57BL/6 mice were infected with AM1 or SS1 strain as well as AM1 followed by SS1 (AM1/SS1) and vice versa.

RESULTS

Mice infected with AM1/SS1 strain exhibited less gastric inflammation and reduced proMMP9 and proMMP3 activities in gastric tissues as compared to SS1/SS1 and SS1/AM1 infected groups. The expression of both MMP9 and MMP3 followed similar trend like activity in infected tissues. Both Th1 and Th17 responses were induced by SS1 strain more profoundly than AM1 strain infection which induced solely Th1 response in spleen and gastric tissues. Moreover, IFN-γ, TNF-α, IL-1β and IL-12 were significantly downregulated in mice spleen and gastric tissues infected by AM1/SS1 compared to SS1/SS1 but not with SS1/AM1 coinfection. Surprisingly, IL-17 level was dampened significantly in AM1/SS1 compared to SS1/AM1 coinfected groups. Furthermore, number of Foxp3⁺ T-regulatory (Treg) cells and immunosuppressive cytokines like IL-10 and TGF-β were reduced in AM1/SS1 compared to SS1/SS1 and SS1/AM1 coinfected mice gastric tissues.

CONCLUSIONS

These data suggested that prior H. pylori cag^- strain infection attenuated the severity of gastric pathology induced by subsequent cag⁺ strain in C57BL/6 mice. Prior AM1 infection induced Th1 cytokine IFN-γ, which reduced the Th17 response induced by subsequent SS1 infection. The reduced gastritis in AM1/SS1-infected mice might also be due to enrichment of AM1- primed Treg cells in the gastric compartment which inhibit Th1 and Th17 responses to subsequent SS1 infection. In summary, prior infection by non-virulent H. pylori strain (AM1) causes reduction of subsequent virulent strain (SS1) infection by regulation of inflammatory cytokines and MMPs expression.

The Role of IL-33-Dependent Inflammation in the Tumor Microenvironment

There is compelling evidence that inflammation contributes to tumorigenesis. Inflammatory mediators within the tumor microenvironment can either promote an antitumor immune response or support tumor pathogenesis. Therefore, it is critical to determine the relative contribution of tumor-associated inflammatory pathways to cancer development. Interleukin-33 (IL-33) is a member of the IL-1 family of cytokines that is released upon tissue stress or damage to operate as an alarmin. IL-33 has been primarily implicated in the induction of type-2 immune responses. However, recent findings have shown a role of IL-33 in several cancers where it may exert multiple functions. In this review, we will present the current knowledge on the role of IL-33 in the microenvironment of different tumors. We will highlight which cells produce and which cells are activated by IL-33 in cancer. Furthermore, we will explain how IL-33 modulates the tumor-associated inflammatory microenvironment to restrain or promote tumorigenesis. Finally, we will discuss the issues to be addressed first before potentially targeting the IL-33 pathway for cancer therapy.

Bisdemethoxycurcumin inhibits ovarian cancer via reducing oxidative stress mediated MMPs expressions

As one main active compound of curcuminoids, Bisdemethoxycurcumin (BDMC) possesses several biological activities, such as anti-inflammation and anti-cancer activities. However, the detailed mechanism of BDMC’s anti-metastasis activity in ovarian cancer has not been clearly elucidated yet. In the present study, cell proliferation, wound healing motility, cell adhesion and invasion with or without BDMC were determined. In addition, western blot was used to examine proteins expressions. The lucigenin-enhanced luminescence was introduced to assess cellular oxidative stress. The luciferase reporter gene assay was introduced to evaluate the transcriptional activity of NF-κB. Finally, BDMC significantly inhibited the adhesion, migration, invasion and metastasis of SKOV-3 cells. Moreover, BDMC inhibited expressions of several degradation-associated proteins, such as matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), CD147, urokinase plasminogen activator (uPA), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), whereas increased expression of tissue inhibitor of metalloproteinase-1 (TIMP-1), in a dose-dependent manner. In addition, BDMC reduced generation of cellular superoxide in a dose-dependent manner. Furthermore, BDMC inhibited the phosphorylation levels of NF-κB p65 and IκB-α, and consequently reduced NF-κB-driven luciferase expression. Collectively, BDMC serves as a therapeutic medicine to suppress ovarian cancer, perhaps via inhibiting cellular oxidative stress and subsequently inactivating NF-κB pathway.

Aurora-A modulates MMP-2 expression via AKT/NF-κB pathway in esophageal squamous cell carcinoma cells

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies. It is necessary to identify new markers for predicting tumor progression and therapeutic molecular targets. It has been reported that overexpressions of Aurora-A and matrix metalloproteinases 2 (MMP-2) may promote the malignant development of tumor. However, the relationship between Aurora-A and MMP-2 expression in tumor patients has not been investigated. In addition, the underlying mechanisms that Aurora-A regulates MMP-2 expression are still not fully elucidated. In this study, we demonstrated that Aurora-A and MMP-2 were overexpressed in ESCC tissues compared with paired normal adjacent tissues (P < 0.0001). Overexpression of Aurora-A was associated with the lymph node metastasis of ESCC (P = 0.01). Significantly, Aurora-A protein expression was positively correlated with MMP-2 protein expression in ESCC tissues (r = 0.66, P < 0.0001) as well as in ESCC cell lines. The level of Aurora-A expression was also positively correlated with the invasion capability of ESCC cells. Furthermore, Aurora-A overexpression significantly increased ESCC cell invasion by the upregulation of MMP-2 expression. In addition, Aurora-A overexpression promoted nuclear factor-kappaB (NF-κB) activation, and Aurora-A-mediated MMP-2 upregulation was abrogated by NF-κB inhibitor. Further analysis showed that activation of NF-κB was severely attenuated by AKT inhibitor in cells overexpressing Aurora-A. Taken together, these data indicate that Aurora-A overexpression upregulates MMP-2 expression through activating AKT/NF-κB signaling pathway in ESCC cells. These findings reveal that Aurora-A may be used as an important indicator for the judgment of malignant behavior of ESCC, and may be an attractive target for cancer therapy.

Matrix metalloproteinase (MMP) -2, -7 and -9 promoter polymorphisms in colorectal cancer in ethnic Kashmiri population - A case-control study and a mini review

Matrix metalloproteinases (MMPs) are proteolytic enzymes that play a pivotal role in the transformation and progression of tumors at all stages, especially during the invasion and metastasis. The aim of this study was to determine the genetic association of MMP2, MMP7 and MMP9 promoter polymorphisms with colorectal cancer (CRC) susceptibility and development risk in ethnic Kashmiri population. The genotype frequencies of MMP2-1306C/T, MMP7-181A/G and MMP9-1562C/T SNPs were compared between 142 CRC patients and 184 healthy controls by using PCR-RFLP method. The association between all the three MMP promoter polymorphisms and the modulation of risk of CRC was found to be significant (p≤0.05). The heterozygous genotype (CT) of MMP2-1306C/T SNP and variant genotype (GG) of MMP7-181A/G SNP showed a significant association with decreased risk for the development of CRC [OR, 0.61 (95%CI, 0.37-1.01); p=0.05 and OR, 0.43 (95%CI, 0.20-0.90); p=0.02, respectively] whereas the heterozygous genotype (CT) of MMP9-1562C/T SNP showed a significant association with increased risk for the development of colorectal cancer [OR, 1.88 (95%CI, 1.11-3.18); p=0.02]. Further, the less common MMP9-1562T allele was found to be significantly associated with an increased risk of colorectal cancer [OR, 1.74 (95%CI, 1.15-2.62); p=0.007]. Our results suggest that these MMP2, MMP7 and MMP9 promoter polymorphisms play a role as one of the key modulators of the risk of developing colorectal cancer in Kashmiri population.

Expression of RECK and MMPs in Hepatoblastoma and Neuroblastoma and Comparative Analysis on the Tumor Metastasis

OBJECTIVE

To explore the expression of RECK and relevant matrix metalloproteinases (MMPs) in hepatoblastoma (HB) and neuroblastoma (NB) and their clinical significance in the tumor metastasis.

MATERIALS AND METHODS

Forty-five wax-stone samples of HB and 43 wax-stone samples of NB removed by surgical resection and confirmed by pathology in Linyi Yishui Central Hospital were selected. According to presence and absence of metastasis, both NB and HB samples were divided into metastatic group and non-metastatic group, namely NB metastatic group (n=28), NB non-metastatic group (n=15), HB metastatic group (n=15) and HB non-metastatic group (n=30). The expression of RECK, membrane type-1 matrix metalloproteinase (MT1-MMP) in HB tissue and RECK, MMP-14 in NB tissue was detected using immunohistochemical method, and the correlation between RECK and MT1-MMP, MMP-14 was analyzed.

RESULTS

The metastatic rate of NB was dramatically higher than that of HB, with statistical significance (P=0.003). The positive rate of RECK expression in NB group (30.2%) was slightly lower than in HB group (40.0%), but no significant difference was presented (P=0.338). The positive rate of MMPs expression in NB metastatic group was evidently higher than in HB metastatic group (P=0.024). The results of Spearman correlation analysis revealed that the expression of RECK in HB and NB tissues had a significantly-negative correlation with MT1-MMP and MMP-14, respectively (r=-0.499, P=0.012; r=-0.636, P=0.000).

CONCLUSIONS

In HB and NB tissues, RECK is expressed lowly, while relevant MMPs highly, and RECK inhibits the tumor invasion and metastasis through negative regulation of relevant MMPs.

RNA-binding motif protein 5 inhibits the proliferation of cigarette smoke-transformed BEAS-2B cells through cell cycle arrest and apoptosis

Cigarette smoking has been shown to be the most significant risk factor for lung cancer. Recent studies have also indicated that RNA-binding motif protein 5 (RBM5) can modulate apoptosis and suppress tumor growth. The present study focused on the role of RBM5 in the regulation of cigarette smoke extract (CSE)-induced transformation of bronchial epithelial cells into the cancerous phenotype and its mechanism of action. Herein, we exposed normal BEAS-2B cells for 8 days to varying concentrations of CSE or dimethylsulfoxide (DMSO), followed by a recovery period of 2 weeks. Next, the RBM5 protein was overexpressed in these transformed BEAS-2B cells though lentiviral infection. Later, the morphological changes, cell proliferation, cell cycle, apoptosis, invasion and migration were assessed. In addition, we analyzed the role of RBM5 in xenograft growth. The expression of RBM5 along with the genes related to cell cycle regulation, apoptosis and invasion were also examined. Finally, our results revealed that BEAS-2B cells exposed to 100 µg/ml CSE acquired phenotypic changes and formed tumors in nude mice, indicative of their cancerous transformation and had reduced RBM5 expression. Subsequent overexpression of RBM5 in these cells significantly inhibited their proliferation, induced G1/S arrest, triggered apoptosis and inhibited their invasion and migration, including xenograft growth. Thus, we established an in vitro model of CSE-induced cancerous transformation and concluded that RBM5 overexpression inhibited the growth of these transformed cells through cell cycle arrest and induction of apoptosis. Therefore, our study suggests the importance of RBM5 in the pathogenesis of smoking-related cancer.

Effects of S-Nitrosoglutathione on the Expression of MMP-1 mRNA in HT1080 Cells during Hypoxic Hypoxia

Synthetic antioxidant S-nitrosoglutathione suppressed the expression of MMP-1 mRNA in HT1080 cells exposed to hypoxic hypoxia; hyperexpression of superoxide dismutase 2 increased and hyperexpression of catalase inhibited the expression of MMP-1 mRNA in HT1080 cells.

IGF-binding protein 2 is a candidate target of therapeutic potential in cancer

Insulin-like growth factor (IGF)-binding protein 2(IGFBP2), a key member of IGF family, has been reported as a notable oncogene in most human epithelium cancers. Increasing evidences suggested that IGFBP2 might be a candidate target of therapuetic potential by regulating key cancer metastasis and invasion-associated signaling networks, but there is still confusion about the mechanism on how IGFBP2 takes part in these processes. In this review, we summarized the current points of view that IGFBP2 functions in signaling pathways during tumorigenesis and tumor progression and discussed its potential clinical applications as a therapeutic target.

Development of a Novel PET Tracer [18F]AlF-NOTA-C6 Targeting MMP2 for Tumor Imaging

Background and Objective

The overexpression of gelatinases, that is, matrix metalloproteinase MMP2 and MMP9, has been associated with tumor progression, invasion, and metastasis. To image MMP2 in tumors, we developed a novel ligand termed [¹⁸F]AlF-NOTA-C6, with consideration that: c(KAHWGFTLD)NH₂ (herein, C6) is a selective gelatinase inhibitor; Cy5.5-C6 has been visualized in many in vivo tumor models; positron emission tomography (PET) has a higher detection sensitivity and a wider field of view than optical imaging; fluorine-18 (¹⁸F) is the optimal PET radioisotope, and the creation of a [¹⁸F]AlF-peptide complex is a simple procedure.

Methods

C6 was conjugated to the bifunctional chelator NOTA (1, 4, 7-triazacyclononanetriacetic acid) for radiolabeling [¹⁸F]AlF conjugation. The MMP2-binding characteristics and tumor-targeting efficacy of [¹⁸F]AlF-NOTA-C6 were tested in vitro and in vivo.

Results

The non-decay corrected yield of [¹⁸F]AlF-NOTA-C6 was 46.2–64.2%, and the radiochemical purity exceeded 95%. [¹⁸F]AlF-NOTA-C6 was favorably retained in SKOV3 and PC3 cells, determined by cell uptake. Using NOTA-C6 as a competitive ligand, the uptake of [¹⁸F]AlF-NOTA-C6 in SKOV3 cells decreased in a dose-dependent manner. In biodistribution and PET imaging studies, higher radioactivity concentrations were observed in tumors. Pre-injection of C6 caused a marked reduction in tumor tissue uptake. Immunohistochemistry showed MMP2 in tumor tissues.

Conclusions

[¹⁸F]AlF-NOTA-C6 was easy to synthesize and has substantial potential as an imaging agent that targets MMP2 in tumors.

Effect of Hypoxia on DDR1 Expression in Pituitary Adenomas

Background

Pituitary adenoma is a common intracranial tumor in neurosurgery. Some pituitary adenomas have the characteristics of invasive growth make them unable to be removed completely by surgery leading to easy relapse. Discoidin domain receptor l (DDR1) is a new kind of tyrosine kinase receptor on the cell surface. DDR1 can be activated by tumor microenvironment signal in tumorigenesis, increasing MMP-2/9 expression and promoting the invasive ability of tumor cells. Anoxia can promote tumor growth and metastasis. This study investigated the impact of anoxic environment DDR1 expression in pituitary adenoma.

Material/Methods

A primary hypoxia pituitary adenoma cell model was established and treated with DDR1 inhibitor nilotinib. Real-time PCR and Western blot were used to detect DDR1 mRNA and protein expression. ELISA was used to detect MMP-2/9 changes. MTT method was used to detect pituitary adenoma cell proliferation. We used a transwell chamber to determine pituitary adenoma cell invasion ability.

Results

DDR1 mRNA and protein were significantly overexpressed under hypoxia (P<0.05). MMP-2 and MMP-9 expression was obviously increased in supernatant (P<0.05). Pituitary adenoma cell proliferation and invasive ability improved markedly under hypoxia (P<0.05). Nilotinib could reduce DDR1 expression, decrease MMP-2 and MMP-9 expression, and inhibit pituitary adenoma cells proliferation and invasion.

Conclusions

Hypoxia can increase DDR1 expression in pituitary adenoma cells, leading to improved MMP-2 and MMP-9 secretion, and promoting pituitary adenoma cell proliferation and invasion.

CCL18 promotes the invasion and migration of gastric cancer cells via ERK1/2/NF-κB signaling pathway

CCL18 is a member of CCL chemokines and is frequently overexpressed in cancer. Elevated CCL18 expression has been reported to be associated with poor prognosis of gastric cancer. However, the molecular mechanisms of CCL18 in gastric cancer cells remain elusive. In our study, we found that CCL18 was highly expressed in different gastric cancer cells. CCL18 stimulation dose-dependently enhanced the invasion and migration of MGC-803 cells. Knockdown of endogenous CCL18 inhibited the invasion and migration of MGC-803 cells, whereas overexpression of CCL18 promoted the invasion and migration of MKN28 cells. We further found that CCL18 increased the expressions of MMP-3 and Slug and decreased the expression of E-cadherin in MGC-803 cells. In addition, CCL18 time-dependently induced activation of ERK1/2, IκBα, and NF-κB. These effects of CCL18 were prevented by ERK1/2 selective inhibitor U0126 as well as NF-κB selective inhibitor BAY117082. Taken together, our findings establish a signaling role for CCL18 in gastric cancer cells and identify that the CCL18/ERK1/2/NF-κB signaling pathway is essential for tumor invasiveness in gastric cancer cells. Thus, our data may provide knowledge for using CCL18 as a novel target for effective diagnosis and treatment of gastric cancer.

Targeting of MMP2 activity in malignant tumors with a 68Ga-labeled gelatinase inhibitor cyclic peptide

INTRODUCTION

Elevated levels of gelatinases (matrix metalloproteinases 2/9, i.e., MMP2 and MMP9) are associated with tumor progression, invasion and metastasis, so these enzymes are potential targets for tumor imaging. The peptide c(KAHWGFTLD)NH2 (herein, C6) is a selective gelatinase inhibitor. Cy5.5-C6 has been visualized in many tumor models in vivo. However, the sensitivity and penetrance of optical imaging are poor. It is well known that positron emission tomography (PET) has a high detection sensitivity and Gallium-68 ((68)Ga) is an optimal PET radioisotope. Thus, in the present study, we developed a novel ligand, (68)Ga-NOTA-C6, to image MMP2 activity in tumors.

METHODS

C6 was conjugated with the bifunctional chelator NOTA (1,4,7-triazacyclononanetriacetic acid) and labeled with (68)Ga. In vitro uptake and binding analyses were performed by using SKOV3 cell lines, coincubating with or without the MMP inhibitor doxycycline. The biodistribution and PET imaging were conducted on SKOV3 ovarian tumor models. MMP2 expression in tumors was analyzed by immunohistochemistry (IHC).

RESULTS

The non-decay corrected yield of (68)Ga-NOTA-C6 was 61.8%-63.3%. (68)Ga-NOTA-C6 was stable in both physiological saline and human serum. The uptake of (68)Ga-NOTA-C6 in SKOV3 cells increased with time, and could be blocked by doxycycline in a dose dependent manner. The results of biodistribution and PET imaging showed that high radioactivity concentrations of (68)Ga-NOTA-C6 occurred in tumors. The ratios of tumor to blood, muscle and ovary and oviduct at 30, 60 and 120min p.i. were 2.78±0.54, 3.86±0.65, 0.48±0.14, and 1.73±0.36, 10.31±3.12, 1.22±0.10, and 2.50±0.78, 7.03±1.85, 0.97±0.25, respectively. The tracer was excreted mainly through the renal system, as evidenced by high levels of radioactivity in the kidneys. These data support the possibility of using (68)Ga-NOTA-C6 in PET to visualize tumors that overexpress MMP2.

CONCLUSIONS

(68)Ga-NOTA-C6 is a potential radiopharmaceutical for the imaging of in vivo MMP2 activity in tumors.

Mieap suppresses murine intestinal tumor via its mitochondrial quality control

Mieap, a novel p53-inducible protein, plays a key role in maintaining healthy mitochondria in various pathophysiological states. Here, we show that Mieap deficiency in Apc^Min/+ mice is strikingly associated with the malignant progression of murine intestinal tumors. To understand the role that Mieap plays in in vivo tumorigenesis, we generated Mieap heterozygous (Apc^Min/+ Mieap^+/−) and homozygous (Apc^Min/+ Mieap^−/−) Apc^Min/+ mice. Interestingly, the Apc^Min/+ mice with the Mieap^+/− and Mieap^−/− genetic background revealed remarkable shortening of the lifetime compared to Apc^Min/+ mice because of severe anemia. A substantial increase in the number and size of intestinal polyps was associated with Mieap gene deficiency. Histopathologically, intestinal tumors in the Mieap-deficient Apc^Min/+ mice clearly demonstrated advanced grades of adenomas and adenocarcinomas. We demonstrated that the significant increase in morphologically unhealthy mitochondria and trace accumulations of reactive oxygen species may be mechanisms underlying the increased malignant progression of the intestinal tumors of Mieap-deficient Apc^Min/+ mice. These findings suggest that the Mieap-regulated mitochondrial quality control plays a critical role in preventing mouse intestinal tumorigenesis.

Association and Prognostic Significance of the Functional -1562C/T Polymorphism in the Promoter Region of MMP-9 in Turkish Patients with Gastric Cancer

Matrix metalloproteinases (MMPs) are a group of zinc-dependent peptidases that participate in matrix turnover in solid malignancies. The aim of this study was twofold. First, we sought to investigate under a case-control design the association between the functional -1562C/T polymorphism in the promoter region of MMP-9 and gastric cancer (GC) in a Turkish sample. Second, we examined its prognostic significance in GC patients. A total of 144 subjects were enrolled in the case-control study (79 GC cases and 65 controls). Overall survival (OS) and progression-free survival (PFS) served as the main outcome measures in the longitudinal study. The MMP-9 -1562C/T polymorphism was genotyped using a polymerase chain reaction-restriction fragment length polymorphism method. The odds ratio (OR) of GC for the CC genotype relative to the CT+TT genotypes was not significant (OR = 0.89, 95 % confidence interval [CI] = 0.44-1.82, P = 0.75). These results did not change after allowance for age and sex in multivariable regression analysis (OR = 0.81, 95 % CI = 0.40-1.94, P = 0.84). When the MMP-9 -1562C/T polymorphism was analyzed among GC patients in relation to OS and PFS, we found no significant differences between subjects with the CC and CT+TT genotypes. In conclusion, the results of our study did not point toward a major role of the MMP-9 -1562C/T polymorphism in the pathogenesis and clinical course of GC in Turkish subjects.

Expression of matrix metalloproteinase-9, cyclooxygenase-2 and vascular endothelial growth factor are increased in gastrointestinal stromal tumors

This study is to investigate the expression of matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in gastrointestinal stromal tumor (GIST). Immunohistochemistry was performed to detect the expression of MMP-9, COX-2 and VEGF. The expression of MMP-9, COX-2 and VEGF was compared among different clinicopathological features of GIST. Spearman rank correlation analysis was conducted to analyze the correlation among MMP-9, COX-2 and VEGF. The positive expression rates of MMP-9, COX-2 and VEGF were 76.9%, 84.6% and 82.7%. The expression levels of MMP-9, COX-2 and VEGF were significantly different among the clinicopathological features of growth pattern, tumor diameter, metastasis, mitotic count and central necrosis (P < 0.05). Their expression levels were higher in GIST tissues with higher levels of malignancy, tumor size, metastasis, mitotic count and central necrosis. However, their expression levels were not significantly different among age, gender, primary tumor site or CD117 expression. Additionally, there were positive correlations between COX-2 and VEGF (r = 0.612, P < 0.01), between COX-2 and MMP-9 (r = 0.592, P < 0.05), and between MMP-9 and VEGF (r = 0.690, P < 0.01). MMP-9, COX-2 and VEGF expression levels are increased in GIST tissues and related with clinicopathological features of GIST.