Activation of matrix metalloproteinase-9 (MMP-9) by neurotensin promotes cell invasion and migration through ERK pathway in gastric cancer. Tumour Biol. 2015;36:6053-6062. [PMID: 25724188 DOI: 10.1007/s13277-015-3282-9]

Comprehensive review of signaling pathways and therapeutic targets in gastrointestinal cancers

Targeted therapy, the milestone in the development of human medicine, originated in 2004 when the FDA approved the first targeted agent bevacizumab for colorectal cancer treatment. This new development has resulted from drug developers moving beyond traditional chemotherapy, and several trials have popped up in the last two decades with an unprecedented speed. Specifically, EGF/EGFR, VEGF/VEGFR, HGF/c-MET, and Claudin 18.2 therapeutic targets have been developed in recent years. Some targets previously thought to be undruggable are now being newly explored, such as the RAS site. However, the efficacy of targeted therapy is extremely variable, especially with the emergence of new drugs and the innovative use of traditional targets for other tumors in recent years. Accordingly, this review provides an overview of the major signaling pathway mechanisms and recent advances in targeted therapy for gastrointestinal cancers, as well as future perspectives.

The role of celastrol in inflammation and diseases

Celastrol is one of the main active ingredients extracted from the plant Tripterygium wilfordii Hook F. A growing number of studies have shown that celastrol has various pharmacological effects, including anti-inflammation, anti-rheumatism, treatment of neurodegenerative diseases, and anti-tumor. This article systematically summarized the mechanism and role of celastrol in lipid metabolism and obesity, rheumatoid arthritis (RA), osteoarthritis (OA), gouty arthritis, inflammatory bowel disease, neurodegenerative diseases, and cancer and other diseases (such as diabetes, respiratory-related diseases, atherosclerosis, psoriasis, hearing loss, etc.). The celastrol played roles in inflammation response, cell apoptosis, autophagy, ferroptosis, and lipid metabolism mainly by acting on chondrocytes, macrophages, mitochondria, and endoplasmic reticulum (ER) through NF-κB, STAT, MAPK, TLR, PI3K-AKT-mTOR, and other signal pathways. This review could provide a reference for the clinical application and further development and utilization of celastrol.

Effect of combined blue light and 5-ALA on mitochondrial functions and cellular responses in B16F1 melanoma and HaCaT cells

In this study, we investigated the effects of blue light and 5-aminolevulinic acid (5-ALA) co-treatment on B16F1 melanoma cells and HaCaT keratinocytes. We focused on cellular responses, including mitochondrial function, DNA integrity, and gene expression. Co-treatment significantly damaged the mitochondria, altered their morphology, induced mitochondrial membrane depolarization, increased intracellular reactive oxygen species, and led to cardiolipin peroxidation in both cell types. This approach promoted DNA fragmentation and apoptosis. However, blue light and co-treatment with 5-ALA did not enhance the formation of cyclobutane pyrimidine dimers, 6-4 photoproducts, or Dewar photoproducts. Moreover, it triggered complex, time-dependent changes in gene expression, particularly the upregulation of MMP-1 and p21 in HaCaT cells. Our findings revealed that blue light and 5-ALA co-treatment caused substantial cellular stress and damage, suggesting their therapeutic potential against melanoma and highlighting the need for caution and precision in their application to avoid harming normal cells. This underscores the necessity for further research to refine therapeutic approaches.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-024-00654-x.

Theranostic Approaches for Gastric Cancer: An Overview of In Vitro and In Vivo Investigations

Gastric cancer (GC) is the second most common cause of cancer-related death worldwide and a serious public health concern. This high death rate is mostly caused by late-stage diagnoses, which lead to poor treatment outcomes. Radiation immunotherapy and targeted therapies are becoming increasingly popular in GC treatment, in addition to surgery and systemic chemotherapy. In this review, we have focused on both in vitro and in vivo research, which presents a summary of recent developments in targeted therapies for gastric cancer. We explore targeted therapy approaches, including integrin receptors, HER2, Claudin 18, and glutathione-responsive systems. For instance, therapies targeting the integrin receptors such as the αvβ3 and αvβ5 integrins have shown promise in enhancing diagnostic precision and treatment efficacy. Furthermore, nanotechnology provides novel approaches to targeted drug delivery and imaging. These include glutathione-responsive nanoplatforms and cyclic RGD peptide-conjugated nanoparticles. These novel strategies seek to reduce systemic toxicity while increasing specificity and efficacy. To sum up, the review addresses the significance of personalized medicine and advancements in gastric cancer-targeted therapies. It explores potential methods for enhancing gastric cancer prognosis and treatment in the future.

Progress and prospects of biomarker-based targeted therapy and immune checkpoint inhibitors in advanced gastric cancer

Gastric cancer and gastroesophageal junction cancer represent the leading cause of tumor-related death worldwide. Although advances in immunotherapy and molecular targeted therapy have expanded treatment options, they have not significantly altered the prognosis for patients with unresectable or metastatic gastric cancer. A minority of patients, particularly those with PD-L1-positive, HER-2-positive, or MSI-high tumors, may benefit more from immune checkpoint inhibitors and/or HER-2-directed therapies in advanced stages. However, for those lacking specific targets and unique molecular features, conventional chemotherapy remains the only recommended effective and durable regimen. In this review, we summarize the roles of various signaling pathways and further investigate the available targets. Then, the current results of phase II/III clinical trials in advanced gastric cancer, along with the superiorities and limitations of the existing biomarkers, are specifically discussed. Finally, we will offer our insights in precision treatment pattern when encountering the substantial challenges.

Streptococcus anginosus promotes gastric inflammation, atrophy, and tumorigenesis in mice

Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse stomach and induced acute gastritis. S. anginosus infection spontaneously induced progressive chronic gastritis, parietal cell atrophy, mucinous metaplasia, and dysplasia in conventional mice, and the findings were confirmed in germ-free mice. In addition, S. anginosus accelerated GC progression in carcinogen-induced gastric tumorigenesis and YTN16 GC cell allografts. Consistently, S. anginosus disrupted gastric barrier function, promoted cell proliferation, and inhibited apoptosis. Mechanistically, we identified an S. anginosus surface protein, TMPC, that interacts with Annexin A2 (ANXA2) receptor on gastric epithelial cells. Interaction of TMPC with ANXA2 mediated attachment and colonization of S. anginosus and induced mitogen-activated protein kinase (MAPK) activation. ANXA2 knockout abrogated the induction of MAPK by S. anginosus. Thus, this study reveals S. anginosus as a pathogen that promotes gastric tumorigenesis via direct interactions with gastric epithelial cells in the TMPC-ANXA2-MAPK axis.

Novel Matrix Metalloproteinase-9 (MMP-9) Inhibitors in Cancer Treatment

Matrix metalloproteinases (MMPs) belong to a family of zinc-dependent proteolytic metalloenzymes. MMP-9, a member of the gelatinase B family, is characterized as one of the most intricate MMPs. The crucial involvement of MMP-9 in extracellular matrix (ECM) remodeling underscores its significant correlation with each stage of cancer pathogenesis and progression. The design and synthesis of MMP-9 inhibitors is a potentially attractive research area. Unfortunately, to date, there is no effective MMP-9 inhibitor that passes the clinical trials and is approved by the FDA. This review primarily focuses on exploring the diverse strategies employed in the design and advancement of MMP-9 inhibitors, along with their anticancer effects and selectivity. To illuminate the essential structural characteristics necessary for the future design of novel MMP-9 inhibitors, the current narrative review highlights several recently discovered MMP-9 inhibitors exhibiting notable selectivity and potency.

NTSR1 glycosylation and MMP dependent cleavage generate three distinct forms of the protein

NTSR1 abnormal expression by cancer cells makes it a strategic target for antitumoral therapies, such as compounds that use NTSR1 binding probes to deliver cytotoxic agents to tumor cells. Success of these therapies relies on NTSR1 protein availability and accessibility; therefore, understanding the protein's biology is crucial. We studied NTSR1 protein in exogenously and endogenously expressing non-tumoral and tumoral cells. We found NTSR1 to be expressed as three distinct protein forms: the NTSR1-high form, a glycosylated protein; the NTSR1-low form, a N-terminally cleaved and de-glycosylated protein; and the NTSR1-LP protein with the MW size predicted by its NTSR1 amino acid sequence. We show that the NTSR1-high form is cleaved by MMPs to generate the NTSR1-low form, a process that is promoted by the Neurotensin (NTS) ligand. In addition, NTS induced the internalization of plasma membrane localized NTSR1 and degradation of NTSR1-low form via the proteasome. Importantly, we found NTSR1-low form to be the most abundant form in the tumoral cells and in PDAC Patient Derived Xenograft, demonstrating its physiopathological relevance. Altogether, our work provides important technical and experimental tools as well as new crucial insights into NTSR1 protein biology that are required to develop clinically relevant NTSR1 targeting anti-tumoral therapies.

In situ quantitative measurements on MMP-9 activity in single living cells by single molecule fluorescence correlation spectroscopy

Matrix metalloproteinase-9 (MMP-9) plays an important role in tumor progression. It is of great significance to establish a sensitive in situ assay strategy for MMP-9 activity in single living cells. Here a novel in situ single molecule spectroscopy method based on the fluorescence correlation spectroscopy (FCS) technique was proposed for measuring the MMP-9 activity at different locations within single living cells, using a fluorescent specific peptide and a reference dye as dual probes. The measurement principle is based on the decrease of the ratiometric translational diffusion time of dual probes in the detection volume due to the peptide cleavage caused by MMP-9. The peptide probe was designed to be composed of an MMP-9 cleavage and cell-penetrating peptide sequence that was labeled with a fluorophore and conjugated with a streptavidin (SAV) molecule. The ratiometric translational diffusion time was used as the measurement parameter to eliminate the effect of intracellular uncertain viscosity. The linear relationship between the ratiometric diffusion time and MMP-9 activity was established, and applied to the determination of enzymatic activity in cell lysates as well as the evaluation of the inhibitory effects of different inhibitors on MMP-9. More importantly, the method was successfully used to dynamically determine MMP-9 activity in single living cells or under the stimulation with phorbol 12-myristate 13-acetate (PMA) and inhibitors.

The Effect of Citrus aurantium on Non-Small-Cell Lung Cancer: A Research Based on Network and Experimental Pharmacology

Purpose

To screen the main active components of Citrus aurantium through a network pharmacology approach, construct a component-disease target network, explore its molecular mechanism for the treatment of non-small-cell lung cancer (NSCLC), and validate it experimentally.

Methods

The active ingredients in Citrus aurantium and the targets of Citrus aurantium and NSCLC were collected through the Traditional Chinese Medicine Systematic Pharmacology Database and Analysis Platform (TCMSP), GeneCards, and OMIM databases. The protein interaction network was constructed using the STRING database, and the component-disease relationship network graph was analyzed using Cytoscape 3.9.1. The Metascape database can be used for GO and KEGG enrichment analyses. The Kaplan-Meier plotter was applied for overall survival analysis of key targets of Citrus aurantium in the treatment of NSCLC. Real-time PCR (RT-PCR) and Western blotting were used to determine the mRNA and protein levels of key targets of Citrus aurantium for the treatment of NSCLC.

Results

Five active ingredients of Citrus aurantium were screened, and 54 potential targets for the treatment of NSCLC were found, of which the key ingredient was nobiletin and the key targets are TP53, CXCL8, ESR1, PPAR-α, and MMP9. GO and KEGG enrichment analyses indicated that the mechanism of nobiletin in treating NSCLC may be related to the regulation of cancer signaling pathway, phosphatidylinositol-3 kinase (PI3K)/protein kinase B (Akt) signaling pathway, lipid and atherosclerosis signaling pathway, and neurodegenerative signaling pathway. The experimental results showed that nobiletin could inhibit the proliferation of NSCLC cells and upregulate the levels of P53 and PPAR-α and suppress the expression of MMP9 (P < 0.05).

Conclusion

Citrus aurantium can participate in the treatment of NSCLC through multiple targets and pathways.

Neurotensin expression, regulation, and function during the ovulatory period in the mouse ovary†

The luteinizing hormone (LH) surge induces paracrine mediators within the ovarian follicle that promote ovulation. The present study explores neurotensin (NTS), a neuropeptide, as a potential ovulatory mediator in the mouse ovary. Ovaries and granulosa cells (GCs) were collected from immature 23-day-old pregnant mare serum gonadotropin primed mice before (0 h) and after administration of human chorionic gonadotropin (hCG; an LH analog) across the periovulatory period (4, 8, 12, and 24 h). In response to hCG, Nts expression rapidly increased 250-fold at 4 h, remained elevated until 8 h, and decreased until 24 h. Expression of Nts receptors for Ntsr1 remained unchanged across the periovulatory period, Ntsr2 was undetectable, whereas Sort1 expression (also called Ntsr3) gradually decreased in both the ovary and GCs after hCG administration. To better understand Nts regulation, inhibitors of the LH/CG signaling pathways were utilized. Our data revealed that hCG regulated Nts expression through the protein kinase A (PKA) and p38 mitogen-activated protein kinase (p38MAPK) signaling pathways. Additionally, epidermal-like-growth factor (EGF) receptor signaling also mediated Nts induction in GCs. To elucidate the role of NTS in the ovulatory process, we used a Nts silencing approach (si-Nts) followed by RNA-sequencing (RNA-seq). RNA-seq analysis of GCs collected after hCG with or without si-Nts identified and qPCR confirmed Ell2, Rsad2, Vps37a, and Smtnl2 as genes downstream of Nts. In summary, these findings demonstrate that hCG induces Nts and that Nts expression is mediated by PKA, p38MAPK, and EGF receptor signaling pathways. Additionally, NTS regulates several novel genes that could potentially impact the ovulatory process.

Signaling pathways and therapeutic interventions in gastric cancer

Gastric cancer (GC) ranks fifth in global cancer diagnosis and fourth in cancer-related death. Despite tremendous progress in diagnosis and therapeutic strategies and significant improvements in patient survival, the low malignancy stage is relatively asymptomatic and many GC cases are diagnosed at advanced stages, which leads to unsatisfactory prognosis and high recurrence rates. With the recent advances in genome analysis, biomarkers have been identified that have clinical importance for GC diagnosis, treatment, and prognosis. Modern molecular classifications have uncovered the vital roles that signaling pathways, including EGFR/HER2, p53, PI3K, immune checkpoint pathways, and cell adhesion signaling molecules, play in GC tumorigenesis, progression, metastasis, and therapeutic responsiveness. These biomarkers and molecular classifications open the way for more precise diagnoses and treatments for GC patients. Nevertheless, the relative significance, temporal activation, interaction with GC risk factors, and crosstalk between these signaling pathways in GC are not well understood. Here, we review the regulatory roles of signaling pathways in GC potential biomarkers, and therapeutic targets with an emphasis on recent discoveries. Current therapies, including signaling-based and immunotherapies exploited in the past decade, and the development of treatment for GC, particularly the challenges in developing precision medications, are discussed. These advances provide a direction for the integration of clinical, molecular, and genomic profiles to improve GC diagnosis and treatments.

Key Genes Associated With Non-Alcoholic Fatty Liver Disease and Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is the most common metabolic and endocrinopathies disorder in women of reproductive age and non-alcoholic fatty liver (NAFLD) is one of the most common liver diseases worldwide. Previous research has indicated potential associations between PCOS and NAFLD, but the underlying pathophysiology is still not clear. The present study aims to identify the differentially expressed genes (DEGs) between PCOS and NAFLD through the bioinformatics method, and explore the associated molecular mechanisms. Methods: The microarray datasets GSE34526 and GSE63067 were downloaded from Gene Expression Omnibus (GEO) database and analyzed to obtain the DEGs between PCOS and NAFLD with the GEO2R online tool. Next, the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis for the DEGs were performed. Then, the protein-protein interaction (PPI) network was constructed and the hub genes were identified using the STRING database and Cytoscape software. Finally, NetworkAnalyst was used to construct the network between the targeted microRNAs (miRNAs) and the hub genes. Results: A total of 52 genes were identified as DEGs in the above two datasets. GO and KEGG enrichment analysis indicated that DEGs are mostly enriched in immunity and inflammation related pathways. In addition, nine hub genes, including TREM1, S100A9, FPR1, NCF2, FCER1G, CCR1, S100A12, MMP9, and IL1RN were selected from the PPI network by using the cytoHubba and MCODE plug-in. Then, four miRNAs, including miR-20a-5p, miR-129-2-3p, miR-124-3p, and miR-101-3p, were predicted as possibly the key miRNAs through the miRNA-gene network construction. Conclusion: In summary, we firstly constructed a miRNA-gene regulatory network depicting interactions between the predicted miRNA and the hub genes in NAFLD and PCOS, which provides novel insights into the identification of potential biomarkers and valuable therapeutic leads for PCOS and NAFLD.

AIM2 Promotes Gastric Cancer Cell Proliferation via the MAPK Signaling Pathway

Background

Gastric cancer (GC) is a highly prevalent tumor type. The dysregulated expression of melanoma deficiency factor 2 (AIM2) has been observed in a range of tumor types. Herein, we explore the role of AIM2 in the regulation of GC progression.

Methods

Gastric cancer cells BGC-823 and MGC-803 in logarithmic growth phase were divided into blank group (control), Control group (NC) and SH-AIM2 group, respectively. Control group and SH-AIM2 group were transfected with AIM2 NC and SH-AIM2, respectively. Nude mice were divided into blank group (control) and SH-AIM2 group, and the treatment methods were the same as above. Differential AIM2 expression in GC tissues was assessed via bioinformatics analyses, after which western blotting was used for analyzing the AIM2 levels in tumor and paracancerous tissues from five stomach cancer patients. In addition, qPCR and protein imprinting were used to assess AIM2 expression levels in GC cells, and AIM2 knockdown was conducted in MGC-803 and BGC-823cells, after which colony formation and EdU incorporation assay were utilized to assess cell proliferation. The oncogenic role of AIM2 was then assessed in mice and validated through immunohistochemical analyses.

Results

GC tissues and cell lines exhibited marked AIM2 overexpression. AIM2 knockdown significantly impaired GC cell proliferation and migration, as confirmed through in vitro assays. In vivo experiments showed that both the increment ability and invasion and migration ability of AIM2 knockdown group were significantly lower than that of control and NC the change of AIM2 protein level would affect the change of MAPK pathway related protein level.

Conclusions

AIM2 knockdown markedly suppresses the proliferation, migration, as well as invasion of GC cells via the inhibition of MAPK signaling, thereby slowing tumor progression. Overall, these results suggest that further analyses of AIM2 may offer clinically valuable insights that can aid in the treatment of human GC.

Anti-Inflammatory Effects of Rhamnetin on Bradykinin-Induced Matrix Metalloproteinase-9 Expression and Cell Migration in Rat Brain Astrocytes

Bradykinin (BK) has been shown to induce matrix metalloproteinase (MMP)-9 expression and participate in neuroinflammation. The BK/MMP-9 axis can be a target for managing neuroinflammation. Our previous reports have indicated that reactive oxygen species (ROS)-mediated nuclear factor-kappaB (NF-κB) activity is involved in BK-induced MMP-9 expression in rat brain astrocytes (RBA-1). Rhamnetin (RNT), a flavonoid compound, possesses antioxidant and anti-inflammatory effects. Thus, we proposed RNT could attenuate BK-induced response in RBA-1. This study aims to approach mechanisms underlying RNT regulating BK-stimulated MMP-9 expression, especially ROS and NF-κB. We used pharmacological inhibitors and siRNAs to dissect molecular mechanisms. Western blotting and gelatin zymography were used to evaluate protein and MMP-9 expression. Real-time PCR was used for gene expression. Wound healing assay was applied for cell migration. 2',7'-dichlorodihydrofluorescein diacetate (H2DCF-DA) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) were used for ROS generation and NOX activity, respectively. Promoter luciferase assay and chromatin immunoprecipitation (ChIP) assay were applied to detect gene transcription. Our results showed that RNT inhibits BK-induced MMP-9 protein and mRNA expression, promoter activity, and cell migration in RBA-1 cells. Besides, the levels of phospho-PKCδ, NOX activity, ROS, phospho-ERK1/2, phospho-p65, and NF-κB p65 binding to MMP-9 promoter were attenuated by RNT. In summary, RNT attenuates BK-enhanced MMP-9 upregulation through inhibiting PKCδ/NOX/ROS/ERK1/2-dependent NF-κB activity in RBA-1.

An integrated analysis of DNA promoter methylation, microRNA regulation, and gene expression in gastric adenocarcinoma

Background

Gastric adenocarcinoma (GAC), a common type of gastric cancer, poses a significant public health threat worldwide. This study aimed to determine the transcriptional regulatory mechanisms of GAC.

Methods

HTSeq-FPKM raw data were obtained from The Cancer Genome Atlas Stomach Adenocarcinoma data collection. Subsequently, the limma package in R was used to identify differentially expressed genes (DEGs). Differentially methylated genes (DMGs), DEGs, and differentially expressed microRNAs (miRNAs) in normal, and tumor tissues of the same patients were screened and compared using R software tools. A functional enrichment analysis was performed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) for various DEGs, DMGs, promoter methylation, and miRNAs. DEG-specific methylation and transcription factors were analyzed using ENCODE ChIP-seq.

Results

DEGs were centrally modified by the histone trimethylation of lysine 27 on histone H3 (H3K27me3). Upstream transcription factors of DEGs were enriched in different ChIP-seq clusters, such as Forkhead Box M1, E2F Transcription Factor 4, and suppressor of zest 12. Integrated regulatory networks of DEGs, promoter methylation, and miRNAs were constructed. Two miRNAs (hsa-mir-1 and hsa-mir-133a) and four DEGs (A disintegrin and metalloproteinase domain 12, transcription factor AP-2 alpha, solute carrier family 5 member 7, and cadherin 19) separately played important roles in the integrated regulatory network. Therefore, these DEGs, DMGs, promoter methylation, and miRNAs may play an important role in GAC pathogenesis.

Conclusions

In summary, the present study results provide insights into the oncogenesis and progression of GAC, thus accelerating the development of novel targeted GAC therapies.

An Immune-Related Signature Predicted Survival in Patients With Kidney Papillary Cell Carcinoma

Immune-related genes are important factors in tumor progression. The main aim of this study was to identify the immune-related genes in kidney papillary cell carcinoma (pRCC) patients. We downloaded RNAseq data and clinical information of pRCC patients from the TCGA database and retrieved the immune-related genes list from Immport. From the data, we mined out 2,468 differential expression genes (DEGs) and 183 immune-related DEGs. Four hub DEGs (NTS, BIRC5, ELN, and CHGA) were identified after conducting Cox analysis and LASSO analysis. Moreover, the prognostic value of the signature based on four hub DEGs was verified using Kaplan–Meier analysis (P = 0.0041 in the training set and p = 0.021 in the test set) and ROC analysis (AUC: 0.957 in 1 year, 0.965 in 2 years, and 0.901 in 3 years in the training set, and 0.963 in 1 year, 0.898 in 2 years, and 0.742 in 3 years in the test set). Furthermore, we found that the high-risk score group had a higher percentage of B cells in the immune component, a higher expression of immune-related genes (CTLA4, LAG3, PDCD1LG2, and TIGIT), and a better immunotherapy response.

Racially Disparate Expression of mTOR/ERK-1/2 Allied Proteins in Cancer

Recent studies revealed that ethnic differences in mechanistic target of rapamycin (mTOR) and extracellular signal-regulated kinase (ERK-1/2) signaling pathways might be associated with the development and progression of different human malignancies. The African American (AA) population has an increased rate of cancer incidence and mortality compared to the Caucasian American (CA) population. Although the socioeconomic differences across different ethnic groups contribute to the disparity in developing different cancers, recent scientific evidence indicates the association of molecular and genetic variations in racial disparities of different human malignancies. The mTOR and ERK-1/2 signaling pathways are one of the well-known oncogenic signaling mechanisms that regulate diverse molecular and phenotypic aspects of normal as well as cancer cells in response to different external or internal stimuli. To date, very few studies have been carried out to explore the significance of racial disparity with abnormal mTOR and ERK-1/2 kinase signaling pathways, which may contribute to the development of aggressive human cancers. In this review, we discuss the differential regulation of mTOR and ERK-1/2 kinase signaling pathways across different ethnic groups, especially between AA and CA populations. Notably, we observed that key signaling proteins associated with mTOR and ERK-1/2 pathway including transforming growth factor-beta (TGF-β), Akt, and VEGFR showed racially disparate expression in cancer patients. Overall, this review article encompasses the significance of racially disparate signaling molecules related to mTOR/ERK1/2 and their potential in developing tailor-made anti-cancer therapies.

Neurotensin: A novel mediator of ovulation?

The midcycle luteinizing hormone (LH) surge initiates a cascade of events within the ovarian follicle which culminates in ovulation. Only mural granulosa cells and theca cells express large numbers of LH receptors, and LH-stimulated paracrine mediators communicate the ovulatory signal within the follicle. Recent reports identified the neuropeptide neurotensin (NTS) as a product of granulosa cells. Here, we demonstrate that granulosa cells were the primary site of NTS expression in macaque ovulatory follicles. Granulosa cell NTS mRNA and protein increased after human chorionic gonadotropin (hCG) administration, which substitutes for the LH surge. To identify ovulatory actions of NTS, a NTS-neutralizing antibody was injected into preovulatory macaque follicles. hCG administration immediately followed, and ovaries were removed 48 hours later to evaluate ovulatory events. Follicles injected with control IgG ovulated normally. In contrast, 75% of NTS antibody-injected follicles failed to ovulate, containing oocytes trapped within unruptured, hemorrhagic follicles. Serum progesterone was unchanged. Of the three NTS receptors, SORT1 was highly expressed in follicular granulosa, theca, and endothelial cells; NTSR1 and NTSR2 were expressed at lower levels. Excessive blood cells in NTS antibody-injected follicles indicated vascular anomalies, so the response of monkey ovarian endothelial cells to NTS was evaluated in vitro. NTS stimulated endothelial cell migration and capillary sprout formation, consistent with a role for NTS in vascular remodeling associated with ovulation. In summary, we identified NTS as a possible paracrine mediator of ovulation. Further investigation of the NTS synthesis/response pathway may lead to improved treatments for infertility and novel targets for contraception.

Neurotensin receptor 1 signaling promotes pancreatic cancer progression

Pancreatic cancer is one of the cancers with the poorest prognosis, with a 5-year survival rate of approximately 5-10%. Thus, it is urgent to identify molecular targets for the treatment of pancreatic cancer. Using serial transplantations in a mouse pancreatic orthotopic inoculation model, we previously produced highly malignant pancreatic cancer sublines with increased tumor-forming abilities in vivo. Here, we used these sublines to screen molecular targets for the treatment of pancreatic cancer. Among the genes with increased expression levels in the sublines, we focused on those encoding cell surface receptors that may be involved in the interactions between cancer cells and the tumor microenvironment. Based on our previous RNA-sequence analysis, we found increased expression levels of neurotensin (NTS) receptor 1 (NTSR1) in highly malignant pancreatic cancer sublines. Furthermore, re-analysis of clinical databases revealed that the expression level of NTSR1 was increased in advanced pancreatic cancer and that high NTSR1 levels were correlated with a poor prognosis. Overexpression of NTSR1 in human pancreatic cancer cells Panc-1 and SUIT-2 accelerated their tumorigenic and metastatic abilities in vivo. In addition, RNA-sequence analysis showed that MAPK and NF-κB signaling pathways were activated upon NTS stimulation in highly malignant cancer sublines and also revealed many new target genes for NTS in pancreatic cancer cells. NTS stimulation increased the expression of MMP-9 and other pro-inflammatory cytokines and chemokines in pancreatic cancer cells. Moreover, the treatment with SR48692, a selective NTSR1 antagonist, suppressed the activation of the MAPK and NF-κB signaling pathways and induction of target genes in pancreatic cancer cells in vitro, while the administration of SR48692 attenuated the tumorigenicity of pancreatic cancer cells in vivo. These findings suggest that NTSR1 may be a prognostic marker and a molecular target for pancreatic cancer treatment.

TMF, a natural dihydroflavonoid isolated from Scutellaria javanica Jungh, stimulates anticancer activity of s180 cancer-bearing mice, induces apoptosis, inhibits invasion and migration on HepG-2 cells

ETHNOPHARMACOLOGICAL RELEVANCE

5-hydroxy-7,8,2',6'-tetramethoxy flavanone (TMF) is a dihydroflavonoid extracted from Scutellaria javanica Jungh. It is a species of genus Scutellaria, and a representative southern herb and Li nationality medicine. The plant has been used as an ethnic medicine in treating cancer and the main components are dihydroflavonoids. However, the underlying mechanisms are yet to be elucidated.

AIM OF THE STUDY

The present study aimed at investigating the efficacy of TMF in cancer and the underlying mechanisms.

MATERIALS AND METHODS

The s180 cancer-bearing mice experiment in vivo was designed to study the tumor growth inhibition of TMF. Also, we investigated the latent mechanism of TMF induced apoptosis and the inhibitory action of TMF on the metastasis and proliferation in HepG-2 cells. The in vitro experimental groups were treated with TMF or hydroxycamptothecine (HCPT) for 24 h. Apoptosis was detected by flow cytometry. Caspase-3 activity was detected by ELISA. The expressions of PCNA, Bcl-2, Bax, p53, E-Cadherin, MMP-9, MMP-2, STAT3, p-STAT3, JAK2, p-JAK2, AKT, p-AKT, ERK1/2 and p-ERK1/2 were examined by Western blot.

RESULTS

After oral administration of TMF in s180 cancer-bearing mice, tumor growth in vivo was suppressed significantly. The MTT assay result and the reduction of PCAN proved that TMF could inhibit HepG-2 cells proliferation. TMF also caused dose-dependent apoptosis on HepG-2 cells. The experimental results showed that the expression of Bcl-2 was reduced, and the expressions of caspase-3, Bax and p53 were increased. Therefore, we speculated that TMF-induced apoptosis might be achieved by regulating the p53-Bcl-2/Bax-caspase-3 pathways. Transwell cell migration and invasion assay showed that treatment with TMF inhibited the invasion and migration in HepG-2 cells. The expressions of MMP-9 and MMP-2 were decreased while that of E-cadherin was enhanced significantly by TMF. Additionally, the expressions of p-JAK2, p-STAT3, p-AKT and p-ERK1/2 were decreased, but those of JAK2, STAT3, AKT and ERK1/2 remained unchanged. Thus, it is indicated that TMF induced apoptosis and inhibited proliferation and metastasis on HepG-2 cells via JAK2/STAT3, MAPK/ERK and PI3K/AKT pathways.

CONCLUSION

The present results demonstrated that TMF could stimulate anticancer activity of s180 cancer-bearing mice, induce apoptosis, and inhibit invasion and migration on HepG-2 cells. Our findings displayed a systematic insight into the mechanisms underlying anticancer action of TMF, and provided a better understanding of its use for cancer.

Neurotensin pathway in digestive cancers and clinical applications: an overview

Initially, NEUROTENSIN (NTS) has been shown to play physiological and biological functions as a neuro-transmitter/modulator in the central nervous system and as an endocrine factor in the periphery, through its binding to two kinds of receptors: NTSR1 and 2 (G protein-coupled receptors) and NTSR3/sortilin (a vacuolar protein-sorting 10-domain receptor). NTS also plays oncogenic roles in many types of cancer, including digestive cancers. In tumor tissues, NTS and NTSR1 expression is higher than in healthy ones and is associated with poor prognosis. NTS and NTRS1 promote cancer progression and play key functions in metastatic processes; they modulate several signaling pathways and they contribute to changes in the tumor microenvironment. Conversely, NTRS2 involvement in digestive cancers is poorly understood. Discovered for mediating NTS biological effects, sortilin recently emerged as a promising target as its expression was found to be increased in various types of cancers. Because it can be secreted, a soluble form of sortilin (sSortilin) appears as a new serum biomarker which, on the basis of recent studies, promises to be useful in both the diagnosis and tumor progression monitoring. More precisely, it appears that soluble sortilin can be associated with other receptors like TRKB. These associations occur in exosomes and trigger the aggressiveness of cancers like glioblastoma, leading to the concept of a possible composite theranostic biomarker. This review summarizes the oncogenic roles of the NTS signaling pathways in digestive cancers and discusses their emergence as promising early diagnostic and/or prognostic biomarkers and therapeutic targets.

Functional Analysis of O-GlcNAcylation in Cancer Metastasis

One common and reversible type of post-translational modification (PTM) is the addition of O-linked β-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), and its dynamic balance is controlled by O-GlcNAc transferase (OGT) and glycoside hydrolase O-GlcNAcase (OGA) through the addition or removal of O-GlcNAc groups. A large amount of research data confirms that proteins regulated by O-GlcNAcylation play a pivotal role in cells. In particularly, imbalanced levels of OGT and O-GlcNAcylation have been found in various types of cancers. Recently, increasing evidence shows that imbalanced O-GlcNAcylation directly or indirectly impacts the process of cancer metastasis. This review summarizes the current understanding of the influence of O-GlcNAc-proteins on the regulation of cancer metastasis. It will provide a theoretical basis to further elucidate of the molecular mechanisms underlying cancer emergence and progression.

MAP Kinases Pathways in Gastric Cancer

Gastric cancer (GC) is turning out today to be one of the most important welfare issues for both Asian and European countries. Indeed, while the vast majority of the disease burden is located in China and in Pacific and East Asia, GC in European countries still account for about 100,000 deaths per year. With this review article, we aim to focus the attention on one of the most complex cellular pathways involved in GC proliferation, invasion, migration, and metastasis: the MAP kinases. Such large kinases family is to date constantly studied, since their discovery more than 30 years ago, due to the important role that it plays in the regulation of physiological and pathological processes. Interactions with other cellular proteins as well as miRNAs and lncRNAs may modulate their expression influencing the cellular biological features. Here, we summarize the most important and recent studies involving MAPK in GC. At the same time, we need to underly that, differently from cancers arising from other tissues, where MAPK pathways seems to be a gold target for anticancer therapies, GC seems to be unique in any aspect. Our aim is to review the current knowledge in MAPK pathways alterations leading to GC, including H. pylori MAPK-triggering to derail from gastric normal epithelium to GC and to encourage researches involved in MAPK signal transduction, that seems to definitely sustain GC development.

Changes in plasma levels of cholecystokinin, neurotensin, VIP and PYY in gastric and colorectal cancer - Preliminary results

Physiological roles of enterohormones such as secretion, absorption and digestion were supported by clinical data. Overexpression of cholecystokinin (CCK), neurotensin (NT) and vasoactive intestinal peptide (VIP) receptors occur in gastrointestinal (GI) malignancies. The aim of the paper was to compare plasma levels of CCK, peptide YY (PYY), VIP and NT in patients with gastrointestinal malignancies and healthy controls. The study included 80 patients (37 men and 43 women) with GI malignancies (20 with gastric and 60 with colorectal cancers). Median age of the patients was 62.9 years (range: 40-85 years). Control group was comprised of 30 healthy persons with median age 59.8 years (range: 40-82 years). Fasting plasma concentrations of CKK, PYY, NT, and VIP were determined at rest, using ELISA kits for automated systems. Comparative analysis of enterohormone levels in patients with various types of gastrointestinal malignancies demonstrated presence of some cancer-specific alterations. Patients with gastric cancers presented with lower plasma concentrations of CCK than healthy controls and individuals from colorectal cancers (p = 0.02). The highest plasma concentrations of neurotensin was found in colorectal cancer patients in comparison to gastric (p = 0.02). The plasma levels of VIP observed in gastric cancer group were lower than in colorectal cancer patients (p = 0.01). Patients with GI malignancies may present with tumor-specific alterations in plasma enterohormone levels.

Ginkgo Biloba Extract Inhibits Metastasis and ERK/Nuclear Factor kappa B (NF-κB) Signaling Pathway in Gastric Cancer

Background

Ginkgo biloba extract (EGb761), a standard extract of the Chinese traditional medicine Ginkgo biloba, plays an anti-tumor role in various cancers. However, whether EGb761 is involved in the invasion and metastasis of gastric cancer remains unclear.

Material/Methods

In the current study, cell viability assay, Western blotting, wound-healing assay, Transwell invasion assay, and orthotopic transplantation model were performed to explore the effects of EGb761 on gastric cancer.

Results

In vitro, the results showed that EGb761 suppressed the proliferation of gastric cancer cells in a dose-dependent manner. Furthermore, the migration and invasiveness were weakened and the protein levels of p-ERK1/2, NF-κB P65, NF-κB p-P65, and MMP2 were decreased by EGb761 or U0126 (an inhibitor of ERK signaling pathway) exposure in gastric cancer cells. Moreover, the combined treatment with EGb761 and U0126 significantly inhibited ERK, NF-κB signaling pathway, and the expression of MMP2 than those of single drug. In vivo, EGb761 inhibited the tumor growth and hepatic metastasis of gastric cancer in the mouse model. Results of immunohistochemistry indicated that the expression of ERK1/2, NF-κB P65 and MMP2 were decreased by EGb761 in the tumor tissues.

Conclusions

EGb761 plays a vital role in the suppression of metastasis and ERK/NF-κB signaling pathway in gastric cancer.

TRIB3 suppresses proliferation and invasion and promotes apoptosis of endometrial cancer cells by regulating the AKT signaling pathway

Objective

The aim of this study was to examine the effect of TRIB3 on proliferation, apoptosis, and migration of endometrial cancer (EC) cells and explore the relationship between TRIB3 and AKT signaling pathway in EC progression.

Methods

Immunohistochemical analysis was performed to measure the expression level of TRIB3 in normal endometrium tissues and EC tissues. Overexpression and shRNA knockdown techniques were applied by transfecting EC cells (ISK and AN3CA), and the effect of TRIB3 on EC cell biological behaviors was evaluated. Cell Counting Kit-8 and colony formation assays were utilized to investigate EC cell proliferation ability, and flow cytometry was performed to assess the apoptosis of EC cells. Moreover, the migration and invasion of EC cells were detected by transwell assay, and the levels of MMP-2 and MMP-9 were measured by ELISA. Additionally, Western blot analysis was carried out to determine the levels of AKT and p-AKT.

Results

The expression level of TRIB3 was higher in EC than normal endometrium tissues, and its overexpression promoted apoptosis and suppressed proliferation of EC cells. Furthermore, TRIB3 retarded the migration and invasion of EC cells and decreased the levels of MMP-2 and MMP-9. Conversely, TRIB3 inhibition enhanced the expression levels of MMP-2 and MMP-9, and proliferation and migration of EC cells but suppressed their apoptosis. Similarly, TRIB3 overexpression reduced while its knockdown increased the level of p-AKT.

Conclusion

TRIB3 inhibited proliferation and migration and promoted apoptosis of EC cells probably through regulating AKT signaling pathway.

High-throughput sequencing identifies aetiology-dependent differences in ductular reaction in human chronic liver disease

Ductular reaction (DR) represents the activation of hepatic progenitor cells (HPCs) and has been associated with features of advanced chronic liver disease; yet it is not clear whether these cells contribute to disease progression and how the composition of their micro-environment differs depending on the aetiology. This study aimed to identify HPC-associated signalling pathways relevant in different chronic liver diseases using a high-throughput sequencing approach. DR/HPCs were isolated using laser microdissection from patient samples diagnosed with HCV or primary sclerosing cholangitis (PSC), as models for hepatocellular or biliary regeneration. Key signals were validated at the protein level for a cohort of 56 patients (20 early and 36 advanced stage). In total, 330 genes were significantly differentially expressed between the HPCs in HCV and PSC. Recruitment and homing of inflammatory cells were distinctly different depending on the aetiology. HPCs in PSC were characterised by a response to oxidative stress (e.g. JUN, VNN1) and neutrophil-attractant chemokines (CXCL5, CXCL6, IL-8), whereas HPCs in HCV were identified by T- and B-lymphocyte infiltration. Moreover, we found that communication between HPCs and macrophages was aetiology driven. In PSC, a high frequency of CCL28-positive macrophages was observed in the portal infiltrate, already in early disease in the absence of advanced fibrosis, while in HCV, HPCs showed a strong expression of the macrophage scavenger receptor MARCO. Interestingly, DR/HPCs in PSC showed more deposition of ECM (e.g. FN1, LAMC2, collagens) compared to HCV, where an increase of pro-invasive genes (e.g. PDGFRA, IGF2) was observed. Additionally, endothelial cells in the vicinity of DR/HPCs showed differential immunopositivity (e.g. IGF2 and INHBA expression). In conclusion, our data shine light on the role of DR/HPCs in immune signalling, fibrogenesis and angiogenesis in chronic liver disease. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

TCF21 inhibits proliferation and chemoresistance through the AKT pathway in human gastric cancer

In a previous study, we showed that transcription factor 21 (TCF21) is methylated and downregulated in human gastric cancer samples and serves as an independent prognostic factor. However, its biological role and potential mechanism in gastric cancer cells remain unexplored. In the current study, we examined TCF21 expression in 6 gastric cancer cell lines. The BGC-823 and SGC-7901 cell lines were selected for small interfering RNA and plasmid transfection, respectively. The results of the Cell Counting Kit-8 assay demonstrated that TCF21 inhibited gastric cancer cell proliferation. Cell cycle analysis suggested that TCF21 inhibited cell cycle progression in gastric cancer cells. The Matrigel invasion assay demonstrated that TCF21 negatively regulated invasion. The cell adhesion assay showed that TCF21 increased cell adhesion. Gastric cancer cells were treated with cisplatin to explore the role of TCF21 in chemoresistance. Cell Counting Kit-8 assay and AnnexinV/propidium iodide analyses showed that TCF21 overexpression sensitized SGC-7901 cells to cisplatin, whereas its depletion reduced sensitivity in BGC-823 cells. JC-1 staining was performed to measure the effect of TCF21 on mitochondrial potential. TCF21 downregulated mitochondrial membrane potential after treatment with cisplatin. Western blot analysis showed that TCF21 overexpression negatively regulated Bcl-xL, phosphorylated extracellular signal regulated kinase, and phosphorylated AKT expression and induced caspase 3 cleavage. LY294002, an AKT inhibitor, blocked the effect of TCF21 on Bcl-xL, caspase 3 and CDDP-induced apoptosis. Nude mice experiments demonstrated that TCF21 inhibited gastric cancer growth in vivo. In conclusion, our results suggest that TCF21 inhibits gastric cancer growth and chemoresistance possibly through the AKT signaling pathway.

miR-516b functions as a tumor suppressor by directly modulating CCNG1 expression in esophageal squamous cell carcinoma

BACKGROUND

miR-516b, as a tumor suppressor in several tumors, its regulatory role in esophageal squamous cell carcinoma (ESCC) hasn't been previously reported.

OBJECTIVE

This study was to investigate the potential role of miR-516b in ESCC.

METHODS

miR-516b expression was measured in ESCC tumor specimens and matched adjacent non-cancerous tissues from 80 ESCC patients. The association between miR-516b and clinicopathological features of these patients was analyzed. The effect of miR-516b was evaluated by cell proliferation, migration, invasion and apoptosis assays in ESCC cell line EC9706 and TE-9. The role of miR-516b in vivo was further studied by constructing ESCC xenograft mice model. The direct target of miR-516b was predicted by public miRNA database and confirmed by luciferase reporter assay. The regulation of miR-516b on the target gene was further confirmed in vitro and in vivo. The expressions of proteins related to cell cycle and apoptosis were analyzed by western blot analysis, and cell migration and invasion were assessed by transwell assays.

RESULTS

miR-516b expression was reduced in ESCC tissues and cells, and correlated with advanced TNM stage, depth of invasion, lymphatic metastasis and poorer overall survival in ESCC patients. miR-516b was upregulated by miR-516b mimics repressing cell proliferation, and inducing G1 cell cycle arrest and apoptosis. miR-516b upregulation also suppressed the growth of ESCC xenograft tumor in nude mice and the invasion of ESCC cells via regulating the epithelial-mesenchymal transition pathway. CCNG1 was identified as a direct downstream target of miR-516b.

CONCLUSION

The results demonstrated miR-516b functions as a tumor suppressor by directly modulating CCNG1 expression in ESCC cells, and may be a novel therapeutic and prognostic biomarker for ESCC.

Bioengineered Submucosal Organoids for In Vitro Modeling of Colorectal Cancer

The physical nature of the tumor microenvironment significantly impacts tumor growth, invasion, and response to drugs. Most in vitro tumor models are designed to study the effects of extracellular matrix (ECM) stiffness on tumor cells, while not addressing the effects of ECM's specific topography. In this study, we bioengineered submucosal organoids, using primary smooth muscle cells embedded in collagen I hydrogel, which produce aligned and parallel fiber topography similar to those found in vivo. The fiber organization in the submucosal organoids induced an epithelial phenotype in spheroids of colorectal carcinoma cells (HCT-116), which were embedded within the organoids. Conversely, unorganized fibers drove a mesenchymal phenotype in the tumor cells. HCT-116 cells in organoids with aligned fibers showed no WNT signaling activation, and conversely, WNT signaling activation was observed in organoids with disrupted fibers. Consequently, HCT-116 cells in the aligned condition exhibited decreased cellular proliferation and reduced sensitivity to 5-fluorouracil chemotherapeutic treatment compared to cells in the unorganized construct. Collectively, the results establish a unique colorectal tumor organoid model to study the effects of stromal topography on cancer cell phenotype, proliferation, and ultimately, chemotherapeutic susceptibility. In the future, such organoids can utilize patient-derived cells for precision medicine applications.

Validation of Neurotensin Receptor 1 as a Therapeutic Target for Gastric Cancer

Gastric cancer is the fifth most common type of malignancy worldwide, and the survival rate of patients with advanced-stage gastric cancer is low, even after receiving chemotherapy. Here, we validated neurotensin receptor 1 (NTSR1) as a potential therapeutic target in gastric cancer. We compared NTSR1 expression levels in sixty different gastric cancer-tissue samples and cells, as well as in other cancer cells (lung, breast, pancreatic, and colon), by assessing NTSR1 expression via semi-quantitative real-time reverse transcription polymerase chain reaction, immunocytochemistry and western blot. Following neurotensin (NT) treatment, we analyzed the expression and activity of matrix metalloproteinase-9 (MMP-9) and further determined the effects on cell migration and invasion via wound-healing and transwell assays. Our results revealed that NTSR1 mRNA levels were higher in gastric cancer tissues than non-cancerous tissues. Both of NTSR1 mRNA levels and expression were higher in gastric cancer cell lines relative to levels observed in other cancer-cell lines. Moreover, NT treatment induced MMP-9 expression and activity in all cancer cell lines, which was significantly decreased following treatment with the NTSR1 antagonist SR48692 or small-interfering RNA targeting NTSR1. Furthermore, NT-mediated metastases was confirmed by observing epithelial-mesenchymal transition markers SNAIL and E-cadherin in gastric cancer cells. NT-mediated invasion and migration of gastric cancer cells were reduced by NTSR1 depletion through the Erk signaling. These findings strongly suggested that NTR1 constitutes a potential therapeutic target for the inhibition of gastric cancer invasion and metastasis.

NRAGE confers poor prognosis and promotes proliferation, invasion, and chemoresistance in gastric cancer

Neurotrophin receptor-interacting melanoma antigen-encoding protein (NRAGE) is a type II melanoma-associated antigen that plays an essential role in various processes, including cell differentiation and apoptosis. NRAGE has been shown to act as a cancer-related protein, with complex and apparently contradictory functions in a variety of cancers. In the current study, we examined the expression of NRAGE protein in 169 gastric cancer samples. NRAGE upregulation was correlated with advanced TNM stage, local invasion, and poor survival. Importantly, NRAGE could serve as an independent prognostic factor in patients with gastric cancer. We also examined the expression of NRAGE protein in GES-1 normal gastric epithelial cells and in six gastric cancer cell lines. Inhibition of NRAGE expression by transfection with small interfering RNA reduced the proliferation and invasion of MGC-803 and HGC-27 cells, as demonstrated by CCK-8 and Matrigel invasion assays. NRAGE depletion also sensitized HGC-27 and MGC-803 cells to cisplatin, as shown by CCK-8 and Annexin V/propidium iodide analyses. Western blot analysis also showed that NRAGE depletion negatively regulated Bcl-2 and p-ERK and upregulated ZO-1 and p27 expression levels. In conclusion, our results suggest that NRAGE acts as a tumor promoter in gastric cancer by facilitating cancer invasion and chemoresistance, possibly through regulation of p-ERK and Bcl-2.

Oncogenic role of neurotensin and neurotensin receptors in various cancers

Neurotensin (NTS) has long been recognized as a neurotransmitter or neuromodulator in the central nervous system and as an endocrine agent in the periphery via actions mediated through neurotensin receptors (NTSRs). Many studies support a role for NTS in the endocrine, autocrine and paracrine growth stimulation of cancer, with oncogenic actions described for NTS in different types of cancers and cancer cell lines at each step of cancer progression, ranging from tumour growth and survival to metastatic spread. The mechanisms underlying the effects of the NTS/NTSR system in cell proliferation, migration and invasion, as well as the anti-apoptotic effects of this system, have been elucidated in different types of cancers, and include mitogen-activated protein kinases, phosphatidylinositol 3-kinase and RhoGTPases. The present mini review summarizes recent findings relating to the oncogenic function of the NTS/NTSR system.

NTS/NTR1 co-expression enhances epithelial-to-mesenchymal transition and promotes tumor metastasis by activating the Wnt/β-catenin signaling pathway in hepatocellular carcinoma

Neurotensin (NTS) is a neuropeptide distributed in central nervous and digestive systems. In this study, the significant association between ectopic NTS expression and tumor invasion was confirmed in hepatocellular carcinoma (HCC). In primary HCC tissues, the NTS and neurotensin receptor 1 (NTR1) co-expression (NTS⁺NTR1⁺) is a poor prognostic factor correlated with aggressive biological behaviors and poor clinical prognosis. Enhanced epithelial-to-mesenchymal transition (EMT) features, including decreased E-cadherin, increased β-catenin translocation and N-cadherin expression, were identified in NTS⁺NTR1⁺ HCC tissues. Varied NTS-responsible HCC cell lines were established using NTR1 genetically modified Hep3B and HepG2 cells which were used to elucidate the molecular mechanisms regulating NTS-induced EMT and tumor invasion in vitro. Results revealed that inducing exogenous NTS stimulation and enhancing NTR1 expression promoted tumor invasion rather than proliferation by accelerating EMT in HCC cells. The NTS-induced EMT was correlated with the remarkable increase in Wnt1, Wnt3, Wnt5, Axin, and p-GSK3β expression and was significantly reversed by blocking the NTS signaling via the NTR1 antagonist SR48692 or by inhibiting the activation of the Wnt/β-catenin pathway via specific inhibitors, such as TSW119 and DKK-1. SR48692 also inhibited the metastases of NTR1-overexpressing HCC xenografts in the lungs in vivo. This finding implied that NTS may be an important stimulus to promote HCC invasion and metastasis both in vitro and in vivo, and NTS signaling enhanced the tumor EMT and invasion potentials by activating the canonical Wnt/β-catenin signaling pathway. Therefore, NTS may be a valuable therapeutic target to prevent tumor progression in HCC.

Role of matrix Metalloproteinases in pituitary adenoma invasion

Though pituitary adenomas are benign tumors in most cases, a considerable fraction of PAs behave in a malignant-like manner and invade to the adjacent structures in sellar region, especially the cavernous sinuses. Cancer-cell invasion and metastasis remain a great challenge for physicians and surgeons in spite of emerging advances in drug therapy and surgical Treatment. matrix metalloproteinases, as a family of zinc-dependent endopeptidases, have long been known to be associated with tumor invasion and metastasis mainly via breaking down basement membrane in different tissues. Aberrant expression and activation of matrix metalloproteinases have been detected in invasive pituitary adenomas as in malignancy and correlated to tumor invasion. Therefore, matrix metalloproteinases are considered as promising biomarkers for predicting tumor behavior and even drug targets for novel therapeutic strategies. In this review, we give an overview of the expression, function, regulation and clinical prospects of matrix metalloproteinases, especially focusing on the biological network in which matrix metalloproteinases may be abnormally activated in promoting pituitary adenoma invasion.

New extracellular factors in glioblastoma multiforme development: neurotensin, growth differentiation factor-15, sphingosine-1-phosphate and cytomegalovirus infection

Recent years have seen considerable progress in understanding the biochemistry of cancer. For example, more significance is now assigned to the tumor microenvironment, especially with regard to intercellular signaling in the tumor niche which depends on many factors secreted by tumor cells. In addition, great progress has been made in understanding the influence of factors such as neurotensin, growth differentiation factor-15 (GDF-15), sphingosine-1-phosphate (S1P), and infection with cytomegalovirus (CMV) on the 'hallmarks of cancer' in glioblastoma multiforme. Therefore, in the present work we describe the influence of these factors on the proliferation and apoptosis of neoplastic cells, cancer stem cells, angiogenesis, migration and invasion, and cancer immune evasion in a glioblastoma multiforme tumor. In particular, we discuss the effect of neurotensin, GDF-15, S1P (including the drug FTY720), and infection with CMV on tumor-associated macrophages (TAM), microglial cells, neutrophil and regulatory T cells (T_reg), on the tumor microenvironment. In order to better understand the role of the aforementioned factors in tumoral processes, we outline the latest models of intratumoral heterogeneity in glioblastoma multiforme. Based on the most recent reports, we discuss the problems of multi-drug therapy in treating glioblastoma multiforme.

Knockdown of Arf6 increases drug sensitivity and inhibits proliferation, migration and invasion in gastric cancer SGC-7901 cells

ADP-ribosylation factor 6 (Arf6), a member of the ADP-ribosylation factor family, is overexpressed in different types of cancer cell and promotes invasion, metastasis and drug resistance. However, the potential functions of Arf6 in gastric cancer (GC), and the molecular mechanism underlying these functions, remain to be fully elucidated. In the present study, the results demonstrated that in vitro knockdown of Arf6 decreased proliferation, colony formation, migration and invasion in SGC-7901 cells. Arf6 knockdown also markedly decreased the activity of the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. Furthermore, knockdown of Arf6 was associated with elevated chemosensitivity of SGC-7901 cells to 5-fluorouracil through inactivation of the ERK1/2 signaling pathway. Taken together, these results suggest that Arf6 is involved in regulating proliferation, migration, invasion and drug resistance in GC, and may be a potential therapeutic target for the treatment of GC.

Transcriptome profiling of cancer tissues in Chinese patients with gastric cancer by high-throughput sequencing

Gastric cancer (GC) is the fifth most common malignancy and the third leading cause of cancer-associated mortality worldwide. Therefore, there is a requirement to identify sufficiently sensitive biomarkers for GC. Genome-wide screening of transcriptome dysregulation among cancerous and normal tissues may provide insights into the underlying molecular mechanisms of GC initiation and progression. At present, high-throughput sequencing techniques have begun to innovate biomedical studies. The RNA-seq method has become an advanced approach in medical studies; it is capable of the accurate detection of gene expression levels. The present study used RNA-seq to evaluate the transcriptional changes between tumor and matched normal samples, and these changes were confirmed by differentially expressed genes in larger samples using the results of sequencing. In total, the upregulation of 28 mRNAs and downregulation of 22 mRNAs between cancerous and normal tissue samples were identified. Subsequently, five differentially expressed genes were selected to verify in large samples and cadherin-1 (CDH1) was selected to detect protein expression levels. The results revealed that CDH1, cyclooxygenase-2 and matrix metalloproteinase genes had significantly higher expression levels, whereas the expression levels of dermatopontin and transforming growth factor β receptor 2 were decreased in GC samples. In particular, CDH1 demonstrated a 36-fold higher expression level in cancer tissues. The western blotting results also revealed high CDH1 expression levels in the validation cohorts. Furthermore, these genes are highly enriched in certain gene ontology categories, including the digestive system process, secretion and digestion. The present study provided a preliminary survey of the transcriptome of Chinese patients with GC, which may improve the detection of aberrant gene expression in GC and the understanding of the mechanisms of tumorigenesis.

Expression and function of transforming growth factor‑β‑activated protein kinase 1 in gastric cancer

The present study aimed to investigate the expression and role of transforming growth factor (TGF) ‑β‑activated protein kinase 1 (TAK1) in human gastric cancer. Immunohistochemistry was performed to investigate the expression of TAK1 in surgical specimens of human gastric cancer tissue and adjacent normal tissue. The association between TAK1 and clinicopathologic factors was analyzed and the association between TAK1 expression and the overall survival rates was evaluated using Kaplan‑Meier curves. In addition, the effect of the TAK1 selective inhibitor 5Z‑7‑oxozeaenol (OZ) on the biological characteristics of MGC803 human gastric cancer cells in vitro were investigated. The role of TAK1 in gastric cancer cell proliferation, apoptosis and invasion were determined by cell proliferation assays, flow cytometry analysis and transwell invasion assays, respectively. The findings of the present study demonstrated that the positive expression rate of TAK1 in gastric cancer and adjacent normal tissues was 70.5 and 25.9%, respectively. Furthermore, TAK1 expression was significantly associated with advanced N stage and pathological stage (P<0.05). Survival analysis of 139 patients with gastric cancer indicated a lower overall survival rate of patients in the TAK1‑positive group compared with the TAK1‑negative group (P<0.05). In addition, treatment with the TAK1 selective inhibitor OZ reduced the proliferation and invasion abilities of MGC803 cells and significantly reduced the expression levels of phosphorylated‑TAK1 (Thr187), nuclear p65, cyclin D1, Bcl‑2 apoptosis regulator and matrix metallopeptidase (MMP)9 (P<0.05). OZ treatment significantly increased the expression levels of cytosolic cytochrome c and cleaved caspase 3 and the apoptosis rate in MGC803 cells (P<0.05). In conclusion, these findings suggest that increased TAK1 expression may be involved in the progression of gastric cancer; therefore, TAK1 may be used as a future therapeutic target for gastric cancer treatment.

Sensitive Detection of MMP9 Enzymatic Activities in Single Cell-Encapsulated Microdroplets as an Assay of Cancer Cell Invasiveness

Matrix metalloproteinases (MMPs) are typically up-regulated in cancer cells, and play a critical role in assisting metastasis by the breakdown of the extracellular matrix. Here we report an effective strategy for cell invasiveness assay by integrating MMP9 functional activity analysis with single cell-encapsulated microdroplets. A flow focusing capillary microfluidic device has been assembled using "off-the-shelf" fluidic components for high-throughput generation of microdroplets. Tumor cells, MMP9 specific peptides, and other cofactors can be loaded into the device and encapsulated into individual droplets as dynamic microreactors for proteolytic cleavage of the substrate. This design allows for rapid and robust detection of MMP9 enzymatic activities by fluorescent signals in a few minutes. It represents the first demonstration of quantifying MMP9 enzymatic activities at the single cell level with a high throughput performance. This new technique promises functional evaluation of cancer cell invasiveness for important diagnostic or prognostic applications.

Evidence of a Cell Surface Role for Hsp90 Complex Proteins Mediating Neuroblast Migration in the Subventricular Zone

In most mammalian brains, the subventricular zone (SVZ) is a germinative layer that maintains neurogenic activity throughout adulthood. Neuronal precursors arising from this region migrate through the rostral migratory stream (RMS) and reach the olfactory bulbs where they differentiate and integrate into the local circuitry. Recently, studies have shown that heat shock proteins have an important role in cancer cell migration and blocking Hsp90 function was shown to hinder cell migration in the developing cerebellum. In this work, we hypothesize that chaperone complexes may have an important function regulating migration of neuronal precursors from the subventricular zone. Proteins from the Hsp90 complex are present in the postnatal SVZ as well as in the RMS. Using an in vitro SVZ explant model, we have demonstrated the expression of Hsp90 and Hop/STI1 by migrating neuroblasts. Treatment with antibodies against Hsp90 and co-chaperone Hop/STI1, as well as Hsp90 and Hsp70 inhibitors hinder neuroblast chain migration. Time-lapse videomicroscopy analysis revealed that cell motility and average migratory speed was decreased after exposure to both antibodies and inhibitors. Antibodies recognizing Hsp90, Hsp70, and Hop/STI1 were found bound to the membranes of cells from primary SVZ cultures and biotinylation assays demonstrated that Hsp70 and Hop/STI1 could be found on the external leaflet of neuroblast membranes. The latter could also be detected in conditioned medium samples obtained from cultivated SVZ cells. Our results suggest that chaperones Hsp90, Hsp70, and co-chaperone Hop/STI1, components of the Hsp90 complex, regulate SVZ neuroblast migration in a concerted manner through an extracellular mechanism.

Inhibition of neurotensin receptor 1 induces intrinsic apoptosis via let-7a-3p/Bcl-w axis in glioblastoma

Backgroud:

Glioblastoma is a kind of highly malignant and aggressive tumours in the central nervous system. Previously, we found that neurotensin (NTS) and its high-affinity receptor 1 (NTSR1) had essential roles in cell proliferation and invasiveness of glioblastoma. Unexpectedly, cell death also appeared by inhibition of NTSR1 except for cell cycle arrest. However, the mechanisms were remained to be further explored.

Methods:

Cells treated with SR48692, a selective antagonist of NTSR1, or NTSR1 shRNA were stained with Annexin V-FITC/PI and the apoptosis was assessed by flow cytometry. Cytochrome c release was detected by using immunofluorescence. Mitochondrial membrane potential (MMP, ΔΨm) loss was stained by JC-1 and detected by immunofluorescence or flow cytometry. Apoptosis antibody array and microRNA microarray were performed to seek the potential regulators of NTSR1 inhibition-induced apoptosis. Interaction between let-7a-3p and Bcl-w 3′UTR was evaluated by using luciferase assay.

Results:

SR48692 induced massive apoptosis, which was related to mitochondrial cytochrome c release and MMP loss. Knockdown of NTSR1 induced slight apoptosis and significant MMP loss. In addition, NTSR1 inhibition sensitised glioblastoma cells to actinomycin D or doxorubicin-induced apoptosis. Consistently, NTSR1 inhibition-induced mitochondrial apoptosis was accompanied by downregulation of Bcl-w and Bcl-2. Restoration of Bcl-w partly rescued NTSR1 deficiency-induced apoptosis. In addition, NTSR1 deficiency promoted higher let-7a-3p expression and inhibition let-7a-3p partly rescued NTSR1 inhibition-induced apoptosis. In addition, let-7a-3p inhibition promoted 3′UTR activities of Bcl-w and the expression of c-Myc and LIN28, which were the upstream of let-7a-3p, decreased after NTSR1 inhibition.

Conclusions:

NTSR1 had an important role in protecting glioblastoma from intrinsic apoptosis via c-Myc/LIN28/let-7a-3p/Bcl-w axis.

Sanguinarine inhibits growth and invasion of gastric cancer cells via regulation of the DUSP4/ERK pathway

Sanguinarine, a bioactive benzophenanthridine alkaloid extracted from plants of the Papaveraceae family, has shown antitumour effects in multiple cancer cells. But the therapeutic effects and regulatory mechanisms of sanguinatine in gastric cancer (GC) remain elusive. This study was aimed to investigate the correlation of dual‐specificity phosphatase 4 (DUSP4) expression with clinicopathologic features and overall survival in patients with GC and explore the effects of sanguinarine on tumour growth and invasion in GC cells (SGC‐7901 and HGC‐27) and underlying molecular mechanisms. Immunohistochemical analysis showed that decreased DUSP4 expression was associated with the sex, tumour size, depth of invasion and distant metastasis in patients with GC. Functional experiments including CCK‐8, Transwell and flow cytometry analysis indicated that sanguinarine or DUSP4 overexpression inhibited GC cell viability and invasive potential, and induced cell apoptosis and cycle arrest in S phase, but DUSP4 knockdown attenuated the antitumour activity of sanguinarine. Further observation demonstrated that sanguinarine up‐regulated the expression of DUSP4 and Bcl‐2‐associated X protein (Bax), but down‐regulated phosphorylated extracellular signal‐regulated kinase (p‐ERK), proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 2 (MMP‐2) and B‐cell lymphoma 2 (Bcl‐2) expression. Taken together, our findings indicate that sanguinarine inhibits growth and invasion of GC cells through regulation of the DUSP4/ERK pathway, suggesting that sanguinarine may have potential for use in GC treatment.

Epigenetically downregulated Semaphorin 3E contributes to gastric cancer

Axon guidance protein Semaphorin 3E (Sema3E) promotes tumor metastasis and suppresses tumor cell death. Here, we demonstrated that Sema3E was decreased in gastric cancer. Its levels were inversely associated with tumor progression. Levels of Sema3E were associated with low p300 and high class I histone deacetylase (class I HDAC). Ectopic expression of Sema3E inhibited proliferation and colony formation of gastric cancer cell lines in vitro and xenografts in vivo. Sema3E overexpression inhibited migration and invasion of gastric cancer cells, which was associated with induction of E-cadherin and reduction of Akt and ERK1/2 phosphorylation. We suggest that silencing of Sema3E contributes to the pathogenesis of gastric cancer.

Tspan9 inhibits the proliferation, migration and invasion of human gastric cancer SGC7901 cells via the ERK1/2 pathway

Tetraspanins are a heterogeneous group of 4-transmembrane proteins that recruit other cell surface receptors and signaling proteins into tetraspanin-enriched microdomains (TEMs). TEMs of various types are involved in the regulation of cell growth, migration and invasion of several tumor cell types, both as suppressors or promotors. Tetraspanin 9 (Tspan9, NET-5, PP1057), a member of the transmembrane 4 superfamily (TM4SF) of tetraspanins, reportedly regulates platelet function in concert with other platelet tetraspanins and their associated proteins. Our previous study demonstrated that Tspan9 is also expressed in gastric cancer (GC), but the role of Tspan9 in GC has not been well characterized. In this study, we investigated the influence of Tspan9 on proliferation, migration and invasion of human gastric cancer SGC7901 cells using CCK-8 assay, cell cycle analysis, wound-healing assay and Transwell assay. Western blot analysis and ELISA assay were also performed to identify the potential mechanisms involved. The proliferation, migration and invasion of human gastric cancer SGC7901 cells were significantly inhibited by overexpression of Tspan9. In addition, Tspan9 downregulated the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and the secretion levels of proteins related to tumor metastasis, such as matrix metalloproteinase-9 (MMP-9) and urokinase plasminogen activator (uPA). Our study indicated that Tspan9 inhibited SGC7901 cell proliferation, migration and invasion through the ERK1/2 pathway.