The role of matrix metalloproteinase 2 on the survival of patients with non-small cell lung cancer: a systematic review with meta-analysis

Metabolism and Anticancer Mechanisms of Selocompounds: Comprehensive Review

Selenium (Se) is an essential micronutrient with several functions in cellular and molecular anticancer processes. There is evidence that Se depending on its chemical form and the dosage use could act as a modulator in some anticancer mechanisms. However, the metabolism of organic and inorganic forms of dietary selenium converges on the main pathways. Different selenocompounds have been reported to have crucial roles as chemopreventive agents, such as antioxidant activity, activation of apoptotic pathways, selective cytotoxicity, antiangiogenic effect, and cell cycle modulation. Nowadays, great interest has arisen to find therapies that could enhance the antitumor effects of different Se sources. Herein, different studies are reported related to the effects of combinatorial therapies, where Se is used in combination with proteins, polysaccharides, chemotherapeutic agents or as nanoparticles. Another important factor is the presence of single nucleotide polymorphisms in genes related to Se metabolism or selenoprotein synthesis which could prevent cancer. These studies and mechanisms show promising results in cancer therapies. This review aims to compile studies that have demonstrated the anticancer effects of Se at molecular levels and its potential to be used as chemopreventive and in cancer treatment.

Thrombospondin-2 acts as a bridge between tumor extracellular matrix and immune infiltration in pancreatic and stomach adenocarcinomas: an integrative pan-cancer analysis

Background

Thrombospondin-2 (THBS2) is a versatile glycoprotein that regulates numerous biological functions, including the apoptosis-proliferation balance in endothelial cells, and it has been linked to tumor angiogenesis. However, the exact role of THBS2 in human cancer remains unknown. This study aimed to determine THBS2 expression in a pan-cancer analysis and its association with pan-cancer prognosis and to further identify its possible roles in tumor immunity and the extracellular matrix (ECM).

Methods

Data on THBS2 expression in cancers and normal tissues were downloaded from the Genotype-Tissue Expression portal and UCSC Xena visual exploration tool and analyzed using the ONCOMINE database, Perl programming language, and Gene Expression Profiling and Interactive Analyses vision 2 webserver. In addition, survival prognosis was analyzed using the survival, survminer, limma, and forestplot packages in R v. 4.0.3.Immune and matrix components were also analyzed using R v. 4.0.3. Most importantly, we partially validated the role and mechanism of THBS2 in pancreatic and gastric cancers in vitro using PANC1 and BGC-823 cell lines.

Results

THBS2 was significantly overexpressed in 17 of the 33 investigated cancers and linked to a poor prognosis in pan-cancer survival analysis. High THBS2 expression was an independent unfavorable prognostic factor in kidney renal papillary cell, mesothelioma, and stomach and pancreatic adenocarcinomas. Immune infiltration and THBS2 expression were also related. THBS2 expression has been linked to immune and stromal scores and immune checkpoint markers in various cancers. The protein–protein interaction network revealed that THBS2 is associated with multiple ECM and immune proteins. THBS2 knockdown decreased the expression of CD47 and matrix metallopeptidase 2 (MMP-2) as well as the proliferation, migration, and invasion of PANC1 and BGC-823 cells in vitro.

Conclusions

Our findings suggested that THBS2 might promote cancer progression by remodeling the tumor microenvironment, affecting CD47-mediated signaling pathways, activating the pro-tumor functions of a disintegrin and metalloproteinase with thrombospondin motifs, and enhancing MMP-2 expression. Furthermore, it functions as a bridge between the ECM and immune infiltration in cancer and serves as a potential prognostic biomarker for several cancers, especially pancreatic and gastric adenocarcinomas.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02622-x.

Prognostic Role of Matrix Metalloproteinases in Cervical Cancer: A Meta-Analysis

OBJECTIVE

Studies have published the association between the expression of matrix metalloproteinases (MMPs) and the outcome of cervical cancer. However, the prognostic value in cervical cancer remains controversial. This meta-analysis was conducted to evaluate the prognostic functions of MMP expression in cervical cancer.

METHODS

A comprehensive search of PubMed, Embase, and Web of Science databases was conducted to identify the eligible studies according to defined selection and excluding criteria and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Fixed and random effects models were evaluated through the hazard ratios (HRs) and 95% confidence intervals (CIs) to estimate the overall survival (OS), recurrence-free survival (RFS), and progress-free survival (PFS).

RESULTS

A total of 18 eligible studies including 1967 patients were analyzed for prognostic value. Totally 16 selected studies including 21 tests were relevant to the cervical cancer OS, 4 studies focused on RFS, and 1 study on PFS. The combined pooled HRs and 95% CIs of OS were calculated with random-effects models (HR = 1.64, 95% CI = 1.01-2.65, P = .000). In the subgroup analysis for OS, there was no heterogeneity in MMP-2 (I² = .0%, P = .880), MMP-1 (I² = .0%, P = .587), and MMP-14 (I² = 28.3%, P = .248). In MMP-7 and MMP-9, the heterogeneities were obvious (I² = 99.2% (P = .000) and I² = 77.9% (P = .000), respectively). The pooled HRs and 95% CIs of RFS were calculated with fixed-effects models (HR = 2.22, 95% CI = 1.38-3.58, P = .001) and PFS (HR = 2.29, 95% CI = 1.14-4.58, P = .035).

CONCLUSIONS

The results indicated that MMP overexpression was associated with shorter OS and RFS in cervical cancer patients. It suggested that MMP overexpression might be a poor prognostic marker in cervical cancer. Research Registry Registration Number: reviewregistry 1159.

The Role of Cell Proliferation and Extracellular Matrix Accumulation Induced by Food Additive Butylated Hydroxytoluene in Uterine Leiomyoma

Leiomyoma is the most common benign uterine tumor in reproductive-age women. Increasing numbers of studies are focusing on the effects of environmental exposure on the incidence and progression of tumors. One major step taken in the food industry is the addition of food preservatives to maintain freshness. Butylated hydroxytoluene (BHT) is a synthetic phenolic antioxidant, which is widely used as an additive to develop fat-soluble characteristics, as well as in cosmetics and rubber. Previous studies also highlighted that BHT may be related to increased fibrosis capacity and carcinogenic effects. In this study, we explored the effects of the commonly used food additive BHT on leiomyoma progression, and the related mechanism. The exposure of the ELT-3 leiomyoma cell line to BHT for 48 h increased the proliferative effect. Since leiomyoma progression is related to increases in extracellular matrix (ECM) accumulation and matrix metalloproteinase (MMP), BHT could effectively increase ECM-related protein expression, as well as MMP-2 and MMP-9 protein expression. This increase in ECM, in response to BHT, may be linked to the activation of the phosphoinositide 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) signaling pathway. Through PI3K inhibition, BHT’s effect on leiomyoma progression could be partially modulated. These results suggest the harmful effect of BHT exposure on leiomyoma progression may relate to PI3K modulation. However, an in vivo study is necessary to confirm these findings.

Diallyl Disulfide Attenuates Ionizing Radiation-Induced Migration and Invasion by Suppressing Nrf2 Signaling in Non-small-Cell Lung Cancer

Non–small-cell lung cancer (NSCLC) is the leading cause of cancer-associated deaths. Radiotherapy remains the primary treatment method for NSCLC. Despite great advances in radiotherapy techniques and modalities, recurrence and resistance still limit therapeutic success, even low-dose ionizing radiation (IR) can induce the migration and invasion. Diallyl disulfide (DADS), a bioactive component extracted from garlic, exhibits a wide spectrum of biological activities including antitumor effects. However, the effect of DADS on IR-induced migration and invasion remains unclear. The present study reported that IR significantly promoted the migration and invasion of A549 cells. Pretreatment with 40 μM DADS enhanced the radiosensitivity of A549 cells and attenuated IR-induced migration and invasion. In addition, 40 μM DADS inhibited migration-related protein matrix metalloproteinase-2 and 9 (MMP-2/9) expression and suppressed IR-aggravated EMT by the upregulation of the epithelial marker, E-cadherin, and downregulation of the mesenchymal marker, N-cadherin, in A549 cells. Furthermore, DADS was found to inhibit the activation of Nrf2 signaling. Based on our previous results that knockdown of Nrf2 by siRNA suppressed IR-induced migration and invasion in A549 cells, we speculated that DADS attenuated IR-induced migration and invasion by suppressing the activation of Nrf2 signaling in A549 cells.

Cadmium-Associated Molecular Signatures in Cancer Cell Models

The exposure of cancer cells to cadmium and its compounds is often associated with the development of more malignant phenotypes, thereby contributing to the acceleration of tumor progression. It is known that cadmium is a transcriptional regulator that induces molecular reprogramming, and therefore the study of differentially expressed genes has enabled the identification and classification of molecular signatures inherent in human neoplastic cells upon cadmium exposure as useful biomarkers that are potentially transferable to clinical research. This review recapitulates selected studies that report the detection of cadmium-associated signatures in breast, gastric, colon, liver, lung, and nasopharyngeal tumor cell models, as specifically demonstrated by individual gene or whole genome expression profiling. Where available, the molecular, biochemical, and/or physiological aspects associated with the targeted gene activation or silencing in the discussed cell models are also outlined.

Clinical and prognostic features of MMP-2 and VEGF in AEG patients

Adenocarcinoma of the esophagogastric junction (AEG) has been increased in recent years and has become a worldwide problem that seriously affects human health. The purpose of the study is to investigate the clinical and prognostic characteristics of the matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) expression in AEG patients. A total of 69 patients were enrolled in this study. The result showed that the high expression of MMP-2 was significantly associated with tumor differentiation (P < 0.05) and depth of invasion (pT, P < 0.05). The high expression of VEGF was significantly associated with pT (P < 0.05) and lymph node metastasis (pN, P < 0.05). There was a positive correlation between MMP-2 and VEGF expression (P < 0.01). The 5-year survival rate for the 69 AEG patients was 40.6% and it was significantly associated with tumor differentiation (P < 0.05), pN (P < 0.01), pTNM stage (P < 0.01), MMP-2 expression (P < 0.05), and VEGF expression (P < 0.05). Cox multivariate regression demonstrated that tumor differentiation and pN were independent factors for the 5-year survival rate. Our study showed that MMP-2 and VEGF could work synergistically in AEG development.

Exosomes and Lung Cancer: Roles in Pathophysiology, Diagnosis and Therapeutic Applications

Lung cancer is a malignancy with a high morbidity and mortality rate, and affected patients have low survival and poor prognosis. The therapeutic approaches for the treatment of this cancer, including radiotherapy and chemotherapy, are not particularly effective partly due to late diagnosis. Therefore, the search for new diagnostic and prognostic tools is a critical issue. Novel biomarkers, such as exosomes, could be considered as potential diagnostic tools for malignancies, particularly lung cancer. Exosomes are nanovesicles, which are associated with different physiological and pathological conditions. It has been shown that these particles are released from many cells, such as cancer cells, immune cells and to some degree normal cells. Exosomes could alter the behavior of target cells through intercellular transfer of their cargo (e.g. DNA, mRNA, long non-coding RNAs, microRNAs and proteins). Thus, these vehicles may play pivotal roles in various physiological and pathological conditions. The current insights into lung cancer pathogenesis suggest that exosomes are key players in the pathogenesis of this cancer. Hence, these nanovesicles and their cargos could be used as new diagnostic, prognostic and therapeutic biomarkers in the treatment of lung cancer. Besides the diagnostic roles of exosomes, their use as drug delivery systems and as cancer vaccines is under investigation. The present review summarizes the current information on the diagnostic and pathogenic functions of exosomes in lung cancer.

Identification of four methylation-driven genes as candidate biomarkers for monitoring single-walled carbon nanotube-induced malignant transformation of the lung

Long-term exposure to carbon nanotubes (CNTs) has been reported to induce malignant transformation. This study aimed to screen candidate biomarkers for monitoring occupational workers to prevent the development of lung cancer. mRNA (GSE56104) and methylation (GSE153246) profiles of lung epithelial BEAS-2B cells exposed to malignant transformation dose of single-walled CNTs or control medium were downloaded from Gene Expression Omnibus database. A total of 1513 differentially expressed genes (DEGs) and 912 differentially methylated genes (DMGs) were identified using LIMMA method. The weighted correlation network analysis identified blue and turquoise modules were associated with malignant transformation of BEAS-2B cells, 124 DMGs of which were overlapped with DEGs. The mRNA and methylation levels of four methylation-driven DEGs were validated in both lung adenocarcinoma (LUAD) and squamous cell carcinomas (LUSC) of The Cancer Genome Atlas dataset and they were associated with overall survival of LUAD patients. Downregulation of PXMP4 and MCOLN2, while upregulation of MET was confirmed in both LUSC and LUAD via Human Protein Atlas analysis. PXMP4 and MET protein levels were also supported in the proteomic analysis of LUAD. Receiver operating characteristic (ROC) curve analysis showed the combination of four genes may be the optimal biomarker for predicting lung cancer, with the area under ROC curve >0.9. Function analysis revealed BARX2 may interact with CCND1 to regulate cell cycle; MET and PXMP4/MCOLN2 may positively correlate with CCR5/IL-6 or GATA3/HLA-DPB1/HLA-DPA1 to involve immune regulation. In conclusion, these four methylation-driven genes may be candidate prognostic and diagnostic biomarkers for single-walled CNT-related lung cancer.

EpCAM-Targeted 3WJ RNA Nanoparticle Harboring Delta-5-Desaturase siRNA Inhibited Lung Tumor Formation via DGLA Peroxidation

Knocking down delta-5-desaturase (D5D) expression by D5D small interfering RNA (siRNA) has been reported that could redirect the cyclooxygenase-2 (COX-2)-catalyzed dihomo-γ-linolenic acid (DGLA) peroxidation from producing prostaglandin E2 to 8-hydroxyoctanoic acid (8-HOA), resulting in the inhibition of colon and pancreatic cancers. However, the effect of D5D siRNA on lung cancer is still unknown. In this study, by incorporating epithelial cell adhesion molecule (EpCAM) aptamer and validated D5D siRNA into the innovative three-way junction (3WJ) RNA nanoparticle, target-specific accumulation and D5D knockdown were achieved in the lung cancer cell and mouse models. By promoting the 8-HOA formation from the COX-2-catalyzed DGLA peroxidation, the 3WJ-EpCAM-D5D siRNA nanoparticle inhibited lung cancer growth in vivo and in vitro. As a potential histone deacetylases inhibitor, 8-HOA subsequently inhibited cancer proliferation and induced apoptosis via suppressing YAP1/TAZ nuclear translocation and expression. Therefore, this 3WJ-RNA nanoparticle could improve the targeting and effectiveness of D5D siRNA in lung cancer therapy.

Irisin, an exercise myokine, potently suppresses tumor proliferation, invasion, and growth in glioma

Glioblastoma multiforme is the most common and aggressive glial tumor with poor prognosis. Importantly, effective treatment options for glioblastoma are unmet needs. Obesity and low physical activity have been linked with a high risk of cancer, and exercise is related to delayed cancer development and progression. Epidemiological studies have revealed a correlation between exercise and the survival rate of patients with glioblastoma. Nevertheless, the mechanisms by which exercise exerts its anticancer effects in glioblastoma remain unclear. Here, we found that irisin, an exercise-induced myokine, induced G₂ /M cell cycle arrest and increased p21 levels in glioblastoma cells, leading to the inhibition of cell proliferation. In addition, irisin inhibited glioblastoma cell invasion by upregulating TFPI-2 and even reversed the aggressive tumor phenotype promoted by co-cultivation with cancer-associated adipocytes. Furthermore, irisin retarded xenograft glioblastoma tumor growth, and radiolabeled irisin demonstrated specific tumor-targeting capability in vivo. Therefore, this study identified one potential molecular mechanism by which exercise prevents cancer progression via irisin. Intriguingly, irisin has the potential to be developed as a molecular imaging and therapeutic anticancer agent.

Targeting vasculogenic mimicry by phytochemicals: A potential opportunity for cancer therapy

Vasculogenic mimicry (VM) is regarded as a process where very aggressive cancer cells generate vascular-like patterns without the presence of endothelial cells. It is considered as the main mark of malignant cancer and has pivotal role in cancer metastasis and progression in various types of cancers. On the other hand, resistance to the antiangiogenesis therapies leads to the cancer recurrence. Therefore, development of novel chemotherapies and their combinations is urgently needed for abolition of VM structures and also for better tumor therapy. Hence, identifying compounds that target VM structures might be superior therapeutic factors for cancers treatment and controlling the recurrence and metastasis. In recent times, naturally occurring compounds, especially phytochemicals have obtained great attention due to their safe properties. Phytochemicals are also capable of targeting VM structure and also their main signaling pathways. Consequently, in this review article, we illustrated key signaling pathways in VM, and the phytochemicals that affect these structures including curcumin, genistein, lycorine, luteolin, columbamine, triptolide, Paris polyphylla, dehydroeffusol, jatrorrhizine hydrochloride, grape seed proanthocyanidins, resveratrol, isoxanthohumol, dehydrocurvularine, galiellalactone, oxacyclododecindione, brucine, honokiol, ginsenoside Rg3, and norcantharidin. The recognition of these phytochemicals and their safety profile may lead to new therapeutic agents' development for VM elimination in different types of tumors.

Matrix Metalloproteinase-2 Single Nucleotide Polymorphism in Egyptian Non-Hodgkin Lymphoma Patients: Correlation with Clinicopathological Characteristics and Outcome

Non-Hodgkin's lymphoma (NHL) is an exceedingly diversified group of lymphoproliferative neoplasms emerging from B-, T- or natural killer -lymphocytes. This study was done to detect Matrix metalloproteinase-2 (MMP2)-735C/T gene polymorphism in patients with NHL and its relation to the clinicopathological characteristics of the studied patients in addition to detection the association between it and NHL disease susceptibility and progression. Clinico-hematological profiles were done on 50 NHL patients. The genotypes and allelic frequencies of MMP-2 polymorphisms were recognized utilizing Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). PCR products after adding restriction endonuclease were analyzed using QIAxcel advanced (automated) instrument. The CT + TT genotypes and T allele of MMP2 735C/T were statistically significant in patients having advanced clinical stages III/IV compared to patients with stages I/II. Another significance was observed in patients with intermediate high/high IPI score and BM infiltration. Interestingly, patients with MMP2-735C/T genotype exhibit lower rate of survival. Our results demonstrated that MMP2-735C/T polymorphism may potentially affect the progression of NHL. Further larger scale studies are needed.

Matrix metalloproteinase-2: Not (just) a "hero" of the past

The 72-kDa type IV collagenase or gelatinase A is the second member of the matrix metalloproteinase family, MMP-2. Since the discovery of its first two substrates within components of the extracellular matrix, denatured interstitial type I collagen and native type IV collagen, the roles and various levels of regulation of MMP-2 have been intensively studied, mainly in vitro. Its (over)expression in most if not all tumors was considered a hallmark of cancer aggressiveness and boosted investigations aiming at its inhibition. Unfortunately, the enthusiasm subsided like a soufflé after clinical trial failures, mostly because of insufficient knowledge of in vivo MMP-2 activities and detrimental side effects of broad-spectrum MMP inhibition. Nowadays, MMP-2 remains a major topic of interest in research, the second in the MMP family after MMP-9. This review presents a broad overview of the major features of this protease. This knowledge is crucial to identify diagnostic or therapeutic strategies focusing on MMP-2. In this sense, recent publications and clinical trials underline the potential value of measuring circulating or tissular MMP-2 levels as diagnostic or prognostic tools, or as a useful secondary outcome for therapies against other primary targets. Direct MMP-2 inhibition has benefited from substantial progress in the design of more specific inhibitors but their in vivo application remains challenging but certainly worth the efforts it receives.

MicroRNA-130b functions as an oncomiRNA in non-small cell lung cancer by targeting tissue inhibitor of metalloproteinase-2

Non-small cell lung cancer (NSCLC) is the most frequent cause of cancer-related death worldwide. Although many molecular-targeted drugs for NSCLC have been developed in recent years, the 5-year survival rate of patients with NSCLC remains low. Therefore, an improved understanding of the molecular mechanisms underlying the biology of NSCLC is essential for developing novel therapeutic strategies for the treatment of NSCLC. In this study, we examined the role of miR-130b in NSCLC. Our results showed that high expression of miR-130b in clinical specimens was significantly associated with poor overall survival in patients with NSCLC. Moreover, miR-130b expression was significantly increased in NSCLC clinical specimens from patients with vascular and lymphatic invasion. Consistent with this, overexpression of miR-130b promoted invasion and matrix metalloproteinase-2 (MMP-2) activity in A549 cells. Argonaute2 immunoprecipitation and gene array analysis identified tissue inhibitor of metalloproteinase-2 (TIMP-2) as a target of miR-130b. Invasion activity promoted by miR-130b was attenuated by TIMP-2 overexpression in A549 cells. Furthermore, TIMP-2 concentrations in serum were inversely correlated with relative miR-130b expression in tumor tissues from the same patients with NSCLC. Overall, miR-130b was found to act as an oncomiR, promoting metastasis by downregulating TIMP-2 and invasion activities in NSCLC cells.

Antimetastatic effects of Terminalia catappa leaf extracts on cervical cancer through the inhibition of matrix metalloprotein-9 and MAPK pathway

The effects of Terminalia catappa leaf extracts (TCE) have been widely investigated, including its antioxidative, anti-inflammatory, and antidiabetic activity, as well as its antimetastatic effects on several types of human cancer. However, no study has examined the antimetastatic potential of TCE in cervical cancer cells. This study aimed to elucidate the potential antimetastatic properties of ethanol extracts of Terminalia catappa in 12-O-tetradecanoylphorbol-13-acetate treated human cervical cancer cells and investigate the signaling pathway of this process. We demonstrated that TCE elicited very low cytotoxicity and significantly inhibited cellular migration and invasion in human HeLa and SiHa cervical cancer cells. Moreover, the gelatin zymography, reverse transcription-polymerase chain reaction (RT-PCR), and real-time PCR analysis revealed that the activity and mRNA level of matrix metalloproteinase-9 (MMP-9) were inhibited by TCE in a concentration-dependent manner. The Western blot results demonstrated that the highest concentration of TCE (100 μg/ml) reduced the phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) by 46% in the HeLa cell lines. In conclusion, it was revealed that TCE exerted antimetastatic effects on cervical cancer cells by inhibiting the expression of MMP-9 through the ERK1/2 pathway.

HMGA2 promotes glioma invasion and poor prognosis via a long-range chromatin interaction

To identify the function and underlying mechanisms of HMGA2 on the prognosis and invasion of gliomas, HMGA2 was detected by immunohistochemistry. The Kaplan‐Meier and Cox's regression analysis results showed that higher HMGA2 level predicted the poorer outcomes of glioma patients. ChIP‐qPCR, DNA electrophoretic mobility shift assay, chromosome conformation capture, and co‐immunoprecipitation were applied to identify HMGA2‐activated target sites, which were further verified by mRNA and protein expression detection. Transwell and orthotopic implantation were used to investigate the roles of HMGA2 in glioma cells. HMGA2 shRNA transfection inhibited glioblastoma invasion. Mechanistically, we first discovered that HMGA2, together with GCN5, facilitated the invasion of glioma cells via inducing chromatin conformational remodeling of the MMP2 gene promoter and epigenetically activating MMP2 gene transcription. Our results indicated that HMGA2, as a novel GCN5 recognition partner and histone acetylation modulator, may be novel prognostic indicator and promising glioma treatment target.

Anti-metastatic effects of isolinderalactone via the inhibition of MMP-2 and up regulation of NM23-H1 expression in human lung cancer A549 cells

Metastatic lung cancer is a leading cause of mortality and has a mortality rate of ≥90%. Isolinderalactone (ILL) is a sesquiterpene lactone compound that has been used in traditional Chinese medicine. Research has demonstrated that ILL has anti-inflammatory and anti-proliferative properties; however, to the best of our knowledge, studies investigating whether ILL can inhibit lung cancer cell metastasis have not been conducted. In the present study, 1-10 µM ILL was applied in the culturing of the A549 lung cancer cell line to investigate the effects of ILL on the invasion and migration of lung cancer cells, including whether the possible mechanisms of ILL are associated with the expression of matrix metalloproteinase (MMP)-2 and NME/NM23 nucleoside diphosphate kinase 1 (NM23-H1) genes. The results of the present study indicated that ILL inhibited the invasion and migration of the A549 cancer cells and exhibited a dose-response association. ILL also significantly inhibited the protein expression and activity of MMP-2 (P<0.05), exhibiting a trend similar to that of its invasion- and migration-associated properties. Further research revealed that ILL significantly increased the expression of NM23-H1 protein and inhibited the expression of β-catenin protein (P<0.05). The results of the present study is, to the best of our knowledge, the first to confirm that ILL can inhibit the invasion and migration of A549 cancer cells, with the possible mechanisms potentially involving the inhibition of MMP-2 and β-catenin protein expression resulting from the up regulation of NM23-H1 expression.

The effect of the Progesterone-Induced Blocking Factor (PIBF) on E-cadherin expression, cell motility and invasion of primary tumour cell lines

In addition to being immunomodulatory, Progesterone-Induced Blocking Factor (PIBF) plays a role in cell cycle regulation and invasion. The full length protein is associated with the pericentriolar satellites and as such, it is crucial for maintaining the integrity of spindle poles during mitosis. Another suggestive evidence for the involvement of PIBF in tumour progression is the fact that the PIBF gene has been identified on chromosome 13 in the region associated with breast cancer susceptibility. Earlier we showed that PIBF differentially regulates the invasiveness of trophoblast and tumour cell lines. The aim of the present study was to further investigate the role of PIBF in tumour development, using primary ovarian- (OC) and primary lung carcinoma (LC) cell cultures, and JEG-3 choriocarcinoma cell line. In the cultured cells PIBF was knocked down by siRNA treatment, and the impact of PIBF deficiency on MMP-9 activity and E-cadherin expression as well as on invasive and migratory capacity of the cells was tested. In conditioned media of PIBF-deficient JEG-3 cells, LC cells and OC cells MMP-9 activity was reduced to 36% 35%, and 65% respectively compared to controls. Though PIBF knock down did not affect migration, in JEG-3 cells, LC primary cells and OC primary cells PIBF deficiency resulted 20%, 50% and 50% decrease of invasion respectively. PIBF silencing resulted in increased E-cadherin expression, suggesting that by down regulating E-cadherin expression, PIBF might interfere with the cell-cell adhesion mechanisms and by increasing MMP activity induced extracellular matrix degradation, facilitates the invasion of tumour cells.

Selenoproteins and Metastasis

Cancer survival is largely impacted by the dissemination of cancer cells from the original tumor site to secondary tissues or organs through metastasis. Targets for antimetastatic therapies have recently become a focus of research, but progress will require a better understanding of the molecular mechanisms driving metastasis. Selenoproteins play important roles in many of the cellular activities underlying metastasis including cell adhesion, matrix degradation and migration, invasion into the blood and extravasation into secondary tissues, and subsequent proliferation into metastatic tumors along with the angiogenesis required for growth. In this review the roles identified for different selenoproteins in these steps and how they may promote or inhibit metastatic cancers is discussed. These roles include selenoenzyme modulation of redox tone and detoxification of reactive oxygen species, calcium homeostasis and unfolded protein responses regulated by endoplasmic reticulum selenoproteins, and the multiple physiological responses influenced by other selenoproteins.

STIM1 silencing inhibits the migration and invasion of A549 cells

The present study aimed to explore the effects of stromal interaction molecule 1 (STIM1) knockdown on the migration, invasion and metastasis of A549 cells in vitro and in vivo. Western blotting and immunohistochemistry were used to detect protein expression levels. Wound healing and Transwell invasion assays were used to assess the migratory and invasive abilities of A549 cells transfected with STIM1-specific short hairpin (sh)RNA (shSTIM1). In addition, a tail vein metastatic assay was performed. The results demonstrated that the frequency of STIM1 high-expression was significantly increased in metastatic lung cancer tissues (72.2%) compared with in non-metastatic lung cancer tissues (33.0%). STIM1 knockdown inhibited A549 cell migration and invasion in vitro and tumor metastasis in vivo. The protein expression levels of Snail1, Vimentin, matrix metalloproteinase (MMP) 2 and MMP9 were markedly decreased in A549-shSTIM1 compared with in A549 cells transfected with control shRNA (shcon). In addition, the protein expression levels of E-cadherin were markedly increased in A549-shSTIM1 cells compared with in A549-shcon cells. These results suggested that STIM1 knockdown may inhibit the migration and invasion of A549 cells in vitro, and metastasis in vivo.

Blood Droplet-Based Cancer Diagnosis via Proteolytic Activity Measurement in Cancer Progression

Matrix metalloproteinase (MMP) is a key marker and target molecule for cancer diagnosis, as MMP is able to cleave peptide chains resulting in degradation of extracellular matrix (ECM), a necessary step for cancer development. In particular, MMP2 has recently been recognized as an important biomarker for lung cancer. Despite the important role of detecting MMP molecules in cancer diagnosis, it is a daunting task to quantitatively understand a correlation between the status of cancer development and the secretion level of MMP in a blood droplet. Here, we demonstrate a nanoscale cancer diagnosis by nanomechanical quantitation of MMP2 molecules under cancer progression with using a blood droplet of lung cancer patients. Specifically, we measured the frequency dynamics of nanomechanical biosensor functionalized with peptide chains mimicking ECM in response to MMP2 secreted from tumors in lung with different metastasis level. It is shown that the frequency shift of the biosensor, which exhibits the detection sensitivity below 1 nM, enables the quantitation of the secretion level of MMP2 molecules during the progression of cancer cells or tumor growth. More importantly, using a blood droplet of lung cancer patients, nanomechanical biosensor is shown to be capable of depicting the correlation between the secretion level of MMP2 molecules and the level of cancer metastasis, which highlights the cantilever-based MMP2 detection for diagnosis of lung cancer. Our finding will broaden the understanding of cancer development activated by MMP and allow for a fast and point-of-care cancer diagnostics.

Inhibition of MMP-2 Expression Enhances the Antitumor Effect of Sorafenib in Hepatocellular Carcinoma by Suppressing the PI3K/AKT/mTOR Pathway

Sorafenib has been globally approved as the standard treatment for patients with advanced hepatocellular carcinoma (HCC). However, the response rate of HCC patients to sorafenib is limited because of tumor recurrence and metastasis. Therefore, seeking combined therapeutic strategies with sorafenib is necessary to improve the antitumor efficiency. Here we demonstrated that expression of MMP-2 is positively correlated with the migration ability of HCC cells. Cells with a higher MMP-2 expression (SK-HEP-1 cells) were less sensitive to sorafenib than those with lower MMP-2 expression (HepG2 cells). Cotreatment of cells with SB-3CT and sorafenib more strongly inhibited migration ability than with sorafenib treatment alone in both HCC cells with high and low expression of MMP-2. In vivo cell metastasis experiments confirmed the synergistic effects of sorafenib and SB-3CT in reducing lung metastasis of SK-HEP-1 cells. Mechanistically, we showed that the synergistic antitumor effect may be attributed to inhibition of the PI3K/AKT/mTOR signaling pathway, but not the RAF/MEK/ERK signaling pathway. With these results taken together, the current study demonstrates that inhibiting MMP-2 expression can enhance the antitumor effect of sorafenib in HCC cells with a high MMP-2 expression, which may provide a novel strategy to improve therapeutic efficiency in HCC.

Role of Proteases in Lung Disease: A Brief Overview

Proteases play an important role in health and disease of the lung. In the normal lungs, proteases maintain their homeostatic functions that regulate processes like its regeneration and repair. Dysregulation of proteases–antiproteases balance is crucial in the manifestation of different types of lung diseases. Chronic inflammatory lung pathologies are associated with a marked increase in protease activities. Thus, in addition to protease activities, inhibition of anti-proteolytic control mechanisms are also important for effective microbial infection and inflammation in the lung. Herein, we briefly summarize the role of different proteases and to some extent antiproteases in regulating a variety of lung diseases.

Contribution of mammalian selenocysteine-containing proteins to carcinogenesis

Oxidative stress caused by a sharp growth of free radicals in the organism is a major cause underlying the occurrence of all kinds of malignant formations. Selenium is an important essential trace element found in selenoproteins in the form of selenocysteine, an amino acid differing from cysteine for the presence of selenium instead of sulfur and making such proteins highly active. To date the role of selenium has been extensively investigated through studying the functions of selenoproteins in carcinogenesis. Analysis of the obtained results clearly demonstrates that selenoproteins can act as oncosuppressors, but can also, on the contrary, favor the formation of malignant tumors.

Unique roles of Akt1 and Akt2 in IGF-IR mediated lung tumorigenesis

AKT is a serine-threonine kinase that becomes hyperactivated in a number of cancers including lung cancer. Based on AKT's association with malignancy, molecules targeting AKT have entered clinical trials for solid tumors including lung cancer. However, the AKT inhibitors being evaluated in clinical trials indiscriminately inhibit all three AKT isoforms (AKT1-3) and it remains unclear whether AKT isoforms have overlapping or divergent functions. Using a transgenic mouse model where IGF-IR overexpression drives lung tumorigenesis, we found that loss of Akt1 inhibited while loss of Akt2 enhanced lung tumor development. Lung tumors that developed in the absence of Akt2 were less likely to appear as discrete nodules and more frequently displayed a dispersed growth pattern. RNA sequencing revealed a number of genes differentially expressed in lung tumors lacking Akt2 and five of these genes, Actc1, Bpifa1, Mmp2, Ntrk2, and Scgb3a2 have been implicated in human lung cancer. Using 2 human lung cancer cell lines, we observed that a selective AKT1 inhibitor, A-674563, was a more potent regulator of cell survival than the pan-AKT inhibitor, MK-2206. This study suggests that compounds selectively targeting AKT1 may prove more effective than compounds that inhibit all three AKT isoforms at least in the treatment of lung adenocarcinoma.

Non-small cell lung cancer is characterised by a distinct inflammatory signature in serum compared with chronic obstructive pulmonary disease

Development of lung cancer is closely related to smoking in a majority of patients. Most smokers, however, do not develop lung cancer in spite of a high mutational load accumulating in the lung tissue. Here we investigate whether a cancer-specific footprint can be revealed by investigating circulating inflammatory markers in patients with non-small cell lung cancer (NSCLC) compared with patients with chronic obstructive pulmonary disease (COPD), both cohorts characterised by similar smoking history. Serum concentrations of 57 cytokines and matrix metalloproteinases (MMPs) from 43 patients with advanced NSCLC were evaluated by multiplex immunoassays and compared with serum samples from 35 patients with COPD. Unsupervised hierarchical clustering and non-parametric analyses were performed. False discovery rate was used to adjust for multiple testing. Clustering of cytokine and MMP concentrations in the serum revealed a distinct separation of the NSCLC patients from the COPD group. Individual concentrations of thymus and activation-regulated cytokine (C-C motif chemokine ligand 17), Gro-b (C-X-C motif chemokine ligand 2 (CXCL2)), CXCL13, interleukin (IL)-1ra, IL-6, IL-8 (CXCL8), IL-16, IL-17A, macrophage migration inhibitory factor (MIF), granulocyte colony-stimulating factor, platelet-derived growth factor subunit B, MMP-2, MMP-8 and MMP-12 were significantly different in serum from NSCLC and COPD patients. Moreover, the interferon-γ/IL-10 ratio was lower in cancer patients compared with COPD patients, consistent with a cytokine milieu favouring tumour tolerance. Our results suggest that NSCLC is characterised by a distinct inflammatory signature in serum. The different cytokine profiles in NSCLC and COPD patients may represent tumour-promoting and tumour-suppressing immune responses developing in response to mucosal inflammation and mutations induced by smoking.

Migration and epithelial-to-mesenchymal transition of lung cancer can be targeted via translation initiation factors eIF4E and eIF4GI

Metastasis underlies cancer morbidity and accounts for disease progression and significant death rates generally and in non-small cell lung cancer (NSCLC) particularly. Therefore, it is critically important to understand the molecular events that regulate metastasis. Accumulating data portray a central role for protein synthesis, particularly translation initiation (TI) factors eIF4E and eIF4G in tumorigenesis and patients' survival. We have published that eIF4E/eIF4GI activities and consequently NSCLC cell migration are modulated by bone-marrow mesenchymal stem cell secretomes, suggesting a role for TI in metastasis. Here, we aimed to expand our understanding of the TI factors significance to NSCLC characteristics, particularly epithelial-to-mesenchymal transition (EMT) and migration, supportive of metastasis. In a model of NSCLC cell lines (H1299, H460), we inhibited eIF4E/eIF4GI's expressions (siRNA, ribavirin) and assessed NSCLC cell lines' migration (scratch), differentiation (EMT, immunoblotting), and expression of select microRNAs (qPCR). Initially, we determined an overexpression of several TI factors (eIF4E, eIF4GI, eIF4B, and DHX29) and their respective targets in NSCLC compared with normal lung samples (70-350%↑, P<0.05). Knockdown (KD) of eIF4E/eIF4GI in NSCLC cell lines (70%↓, P<0.05) also manifested in decreased target levels (ERα, SMAD5, NFkB, CyclinD1, c-MYC, and HIF1α) (20-50%↓, P<0.05). eIF4E/eIF4GI KD also attenuated cell migration (60-75%↓, P<0.05), EMT promoters (15-90%↓, P<0.05), and enhanced EMT suppressors (30-380%↑, P<0.05). The importance of eIF4E KD to NSCLC phenotype was further corroborated with its inhibitor, ribavirin. Changes in expression of essential microRNAs implicated in NSCLC cell migration concluded the study (20-100%, P<0.05). In summary, targeting eIF4E/eIF4GI reduces migration and EMT, both essential for metastasis, thereby underscoring the potential of TI targeting in NSCLC therapy, especially the already clinically employed agents (ribavirin/4EGI). Comparison of these findings with previously reported effects of eIF4E/eIF4GI KD in multiple myeloma suggests a collective role for these TI factors in cancer progression.

CD147 and matrix-metalloproteinase-2 expression in metastatic and non-metastatic uveal melanomas

Background

Extracellular matrix remodelling regulated by matrix-metalloproteinase (MMP) inducer (CD147) is a crucial process during tumor cell invasion and regulation of blood supply. In this study, we evaluated the correlation of CD147 and MMP-2 expression with major prognostic factors for uveal melanoma and the development of metastasis.

Methods

The expression of CD147 and MMP-2 was analyzed in 49 samples of uveal melanomas. Triple immunofluorescence stainings using markers against glial cells (GFAP), endothelial cells (CD34) and macrophages (CD68) were performed to further analyse the exact localisation of CD147 and MMP-2 positivity. In 28 cases clinical metastatic disease were found. The remaining 21 cases showed no signs of metastatic disease for an average follow-up of 10 years. Correlation analysis (Pearson correlation) was performed to analyse the association of CD147 and MMP-2 expression with known prognostic factors, vasculogenic mimicry (VM), the mature vasculature (von Willebrand Factor) and tumor induced angiogenesis (by means of Endoglin expression).

Results

CD147 and MMP-2 were expressed in 47 (96.0 %) of the uveal melanomas. CD147 up-regulation was significantly correlated with a higher MMP-2 expression. The overall expression analysis revealed no significant difference in the metastatic (p = 0.777) and non-metastatic subgroup (p = 0.585). No correlation of CD147 expression and any system of blood supply was evident. In the non-metastatic sub-group a significant correlation of clustered CD147 positive cells with largest basal diameter (p = 0.039), height (p = 0.047) and TNM-stage (p = 0.013) was evident.

Conclusions

These data may indicate that CD147 regulates MMP-2 expression in uveal melanoma cells.

TM4SF1 Promotes Proliferation, Invasion, and Metastasis in Human Liver Cancer Cells

Transmembrane 4 superfamily member 1 (TM4SF1) is a member of tetraspanin family, which mediates signal transduction events regulating cell development, activation, growth and motility. Our previous studies showed that TM4SF1 is highly expressed in liver cancer. HepG2 cells were transfected with TM4SFl siRNA and TM4SF1-expressing plasmids and their biological functions were analyzed in vitro and in vivo. HepG2 cells overexpressing TM4SF1 showed reduced apoptosis and increased cell migration in vitro and enhanced tumor growth and metastasis in vivo, whereas siRNA-mediated silencing of TM4SF1 had the opposite effect. TM4SF1 exerts its effect by regulating a few apoptosis- and migration-related genes including caspase-3, caspase-9, MMP-2, MMP-9 and VEGF. These results indicate that TM4SF1 is associated with liver tumor growth and progression, suggesting that TM4SF1 may be a potential target for treatment of liver cancer in future.

Proteases as prognostic markers in human and canine cancers

The extracellular matrix (ECM) is composed of several types of proteins, which interact and form dynamic networks. These components can modulate cell behaviour and actively influence the growth and differentiation of tissues. ECM is also important in several pathological processes, such as cancer invasion and metastasis, by creating favourable microenvironments. Proteolysis in neoplastic tissues is mediated by proteinases, whose regulation involves complex interactions between neoplastic cells and non-neoplastic stromal cells. In this review, we discuss aspects of proteinase expression and tumor behaviour in humans and dogs. Different classes of proteases are summarized, with special emphasis being placed on molecules that have been shown to correlate with prognosis, reinforcing the need for a better understanding of the regulation of this microenvironment and its influences in tumor progression and metastasis, which should significantly aid the development of improved prognosis and treatment.

Quercetin metabolites inhibit MMP-2 expression in A549 lung cancer cells by PPAR-γ associated mechanisms

Our previous study demonstrated that quercetin-metabolite-enriched plasma (QP) but not quercetin itself upregulates peroxisome proliferator-activated receptor gamma (PPAR-γ) expression to induce G2/M arrest in A549 cells. In the present study, we incubated A549 cells with QP as well as quercetin-3-glucuronide (Q3G) and quercetin-3'-sulfate (Q3'S), two major metabolites of quercetin, to investigate the effects of quercetin metabolites on cell invasion and migration, the possible mechanisms and the role of PPAR-γ. We also compared the effects of QP with those of quercetin and troglitazone (TGZ), a PPAR-γ ligand. The results showed that QP significantly suppressed cell invasion and migration, as well as matrix metalloproteinases (MMPs)-2 activity and expression in a dose-dependent manner. The effects of 10% QP on those parameters were similar to those of 10μM quercetin and 20μM TGZ. However, QP and TGZ rather than quercetin itself increased the expressions of nm23-H1 and tissue inhibitor of metalloproteinase (TIMP-2). Furthermore, we demonstrated that Q3G and Q3'S also inhibited the protein expression of MMP-2. GW9662, a PPAR-γ antagonist, significantly diminished such an effect of Q3G and Q3'S. Silencing PPAR-γ expression in A549 cells also significantly diminished the suppression effect of Q3G and Q3'S on MMP-2 expression. Taken together, our study demonstrated that QP inhibited cell invasion and migration through nm23-H1/TIMP-2/MMP-2 associated mechanisms. The upregulation of PPAR-γ by quercetin metabolites such as Q3G and Q3'S could play an important role in the effects of QP.

Exosomal miRNAs as biomarkers of recurrent lung cancer

Prognosis of lung cancer still remains grim largely due to recurrence and aggressive metastasis of the disease. In this study, we examined the potential of exosomal miRNAs as biomarkers of recurrent lung cancer. Initially, in vitro miRNA profiles of normal lung (Beas-2b) and lung cancer (H1299) cells and of exosomes isolated from conditioned media were determined. In vivo study involved establishing subcutaneous primary and recurrent lung cancer xenografts in nude mouse model and examining tumor and serum exosomal miRNA alteration in secondary/recurrent lung tumors. A total of 77 miRNAs were observed to be significantly modulated in the H1299 cells (47 miRNA upregulated and 30 downregulated) compared to the Beas-2b cells. The exosomes isolated from conditioned media indicated several miRNAs which were in agreement with cells of origin. A similarity was also observed between miRNAs from serum exosomes and tumors, indicating their origin from the lung tumors. Two miRNAs, miR-21 and miR-155, were found to be significantly upregulated in recurrent tumors compared to primary tumors. These miRNAs were also upregulated in serum exosomes of recurrent tumor-bearing animals versus non-tumor- or primary tumor-bearing animals. Increased expression of the recurrent disease markers were also observed in recurrent tumors compared with primary tumors. Serum exosomes from recurrent tumor mice mirrored its tumor profile in expressing higher levels of these proteins compared with exosomes from primary tumor mice. Our data suggest that exosomal miRNA signatures may be a true representation of a pathological profile of lung cancer; thus, miRNAs could serve as promising biomarkers for non-invasive diagnosis of the disease.

The prognostic role of tissue and serum MMP-1 and TIMP-1 expression in patients with non-small cell lung cancer

PURPOSE

Matrix metalloproteinase (MMP) and tissue inhibitor of matrix metalloproteinase (TIMP) play an important role in tumor invasion and progression. The aim of this study was to evaluate the prognostic role of MMP-1 and TIMP-1 in non-small cell lung cancer (NSCLC). To find out a potential serum biomarker, tissue and serum levels were investigated together.

PATIENTS AND METHODS

For 85 surgically resected NSCLC patients who had pre-operative serum samplings, MMP-1 and TIMP-1 expression were investigated using immunohistochemistry in tumor tissue and ELISA in serum. Tumor cells and surrounding stromal cells were assessed separately.

RESULTS

Higher expression of MMP-1 in tumor cells comparing to stromal cells was related to male gender (P=0.006), ever smoker (P=0.004), and pooly differentiated tumor (P=0.043). For TIMP-1, adenocarcinoma showed higher tumor cell expression, while squamous cell carcinoma showed higher stromal expression (P=0.007). Patients with high carcinoembryonic antigen (CEA) level, the presence of vascular invasion, recurrence or death showed higher serum MMP-1 level. There was no correlation between the tissue and serum levels of MMP-1 and TIMP-1. A tumor/stroma TIMP-1 intensity ratio ≥1 was strongly associated with early recurrence in multivariate analysis (hazard ratio=280.55, 95% confidence intervals; 11.12-7080.45; P=0.001). High serum MMP-1 (≥3,500pg/ml) showed a trend for short overall survival (P=0.080). When serum MMP-1 was combined with CEA level or presence of vascular invasion, its prognostic implication was statistically significant (P=0.045 and P=0.015, respectively).

CONCLUSION

The tumor/stroma TIMP-1 intensity ratio in tissue is useful to predict tumor recurrence. Serum MMP-1 level showed a possibility as a prognostic biomarker.

The role of SOX-2 on the survival of patients with non-small cell lung cancer

BACKGROUND

Lung cancer is the most commonly diagnosed cancer as well as the leading cause of cancer death worldwide. Observational studies on the prognostic role of SOX-2 in non-small-cell lung cancer (NSCLC) are controversial.

METHODS

To clarify the impact of SOX-2 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios and their corresponding 95% confidence intervals (95% CI) were calculated in terms of overall survival.

RESULTS

A total of seven studies with 1,944 patients were evaluable for this meta-analysis. The studies were categorized by histology, disease stage and patient race. Our results suggested that SOX-2 overexpression had a favorable impact on survival of patients with NSCLC, the HR (95% CI) was 0.57 (0.48 to 0.65). However, highly significant heterogeneity was detected among these studies (I(2)=76.7%, P=0.000).

CONCLUSIONS

SOX-2 overexpression indicates a favorable prognosis for patients with NSCLC.

Plasminogen Activator Inhibitor-2 Plays a Leading Prognostic Role among Protease Families in Non-Small Cell Lung Cancer

Background

In lung cancer, uPA, its receptor (uPAR), and the inhibitors PAI-1 and PAI-2 of the plasminogen activator family interact with MMP-2 and MMP-9 of the MMP family to promote cancer progression. However, it remains undetermined which of these markers plays the most important role and may be the most useful indicator to stratify the patients by risk.

Methods

We determined the individual prognostic value of these 6 markers by analyzing a derivation cohort with 98 non-small cell lung cancer patients by immunohistochemical staining. The correlation between the IHC expression levels of these markers and disease prognosis was investigated, and an immunohistochemical panel for prognostic prediction was subsequently generated through prognostic model analysis. The value of the immunohistochemical panel was then verified by a validation cohort with 91 lung cancer patients.

Results

In derivation cohort, PAI-2 is the most powerful prognostic factor (HR = 2.30; P = 0.001), followed by MMP-9 (HR = 2.09; P = 0.019) according to multivariate analysis. When combining PAI-2 and MMP-9, the most unfavorable prognostic group (low PAI-2 and high MMP-9 IHC expression levels) showed a 6.40-fold increased risk of a poor prognosis compared to the most favorable prognostic group (high PAI-2 and low MMP-9 IHC expression levels). PAI-2 and MMP-9 IHC panel could more precisely identify high risk patients in both derivation and validation cohort.

Conclusions

We revealed PAI-2 as the most powerful prognostic marker among PA and MMP protease family even after considering their close relationships with each other. By utilizing a combination of PAI-2 and MMP-9, more precise prognostic information than merely using pathological stage alone can be obtained for lung cancer patients.

Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer.

MicroRNA-29b attenuates non-small cell lung cancer metastasis by targeting matrix metalloproteinase 2 and PTEN

BACKGROUND

Our pilot study using miRNA PCR array found that miRNA-29b (miR-29b) is differentially expressed in primary cultured CD133-positive A549 cells compared with CD133-negative A549 cells.

METHODS

Ten human non-small cell lung cancer (NSCLC) cell lines and samples from thirty patients with NSCLC were analyzed for the expression of miR-29b by quantitative RT-PCR. Bioinformatics analysis combined with tumor metastasis PCR array showed the potential target genes for miR-29b. miR-29b lentivirus and inhibitors were transfected into NSCLC cells to investigate its role on regulating cell proliferation which was measured by CCK-8 assay in vitro and nude mice xenograft tumor assay in vivo. Cell motility ability was evaluated by transwell assay. The target genes of miR-29b were determined by luciferase assay, quantitative RT-PCR and western blot.

RESULTS

Bioinformatics analysis combined with tumor metastasis PCR array showed that matrix metalloproteinase 2 (MMP2) and PTEN could be important target genes of miR-29b. The expression of miR-29b was down regulated in NSCLC tissues compared to the normal tissues. Clinicopathological analysis demonstrated that miR-29b had significant negative correlation with lymphatic metastasis. The gain-of-function studies revealed that ectopic expression of miR-29b decreased cell proliferation, migration and invasion abilities of NSCLC cells. In contrasts, loss-of-function studies showed that inhibition of miR-29b promoted cell proliferation, migration and invasion of NSCLC cells in vitro. Nude mice xenograft tumor assay confirmed that miR-29b inhibited lung cancer growth in vivo. High-invasion (A549-H) and low-invasion (A549-L) NSCLC cell sublines from A549 cells were created by using the repeated transwell assay aimed to confirm the effect of miR-29b on migration and invasion of NSCLC. Furthermore, the dual-luciferase reporter assay demonstrated that miR-29b inhibited the expression of the luciferase gene containing the 3'-UTRs of MMP2 and PTEN mRNA. Western blotting and quantitative RT-PCR indicated that miR-29b down-regulated the expression of MMP2 at the protein and mRNA levels.

CONCLUSION

Taken together, our results demonstrate that miR-29b serves as a tumor metastasis suppressor, which suppresses NSCLC cell metastasis by directly inhibiting MMP2 expression. The results show that miR-29b may be a novel therapeutic candidate target to slow NSCLC metastasis.

SRF-miR‑29b-MMP2 axis inhibits NSCLC invasion and metastasis

MicroRNAs play key roles in tumour metastasis. miR‑29b was previously reported to act as a tumour suppressor or an oncogene in diverse cancers. However, its accurate function and mechanism in metastasis of no-small cell lung cancer (NSCLC) are not well known. In this study, we describe the function of miR‑29b in NSCLC metastasis and its regulatory mechanisms. We found that miR‑29b is downregulated in high-metastatic NSCLC cells and low-expression of miR‑29b in primary NSCLC tissue was correlated with lymph node metastasis. Both gain- and loss-of-function study indicated overexpression of miR‑29b could suppress migration and invasion abilities of high-metastatic NSCLC cells, while downregulation of miR‑29b expression promoted migration and invasion of low-metastatic NSCLC cells in vitro. Moreover, introduction of miR‑29b inhibited high‑metastatic NSCLC cells, in vivo, metastasis to liver and lungs. Mechanistically, miR‑29b, induced by the transcription factor SRF, posttranscriptionally downregulates MMP2 expression by directly targeting its 3'-untranslated regions. These findings indicate a new regulatory mode, whereby miR‑29b, which is inhibited by its upstream transcription factor SRF, was able to promote its direct target MMP2 leading to NSCLC invasion and metastasis.

Prognostic significance of matrix metalloproteinase-7 in gastric cancer survival: a meta-analysis

The prognostic role of matrix metalloproteinase-7 in gastric cancer survival has been widely evaluated. However, the results are controversial. We aimed to set up a meta-analysis to reach a conclusion on the prognostic significance of metalloproteinase-7 in gastric cancer survival as well as its association with clinicopathological parameters. We searched popular databases from 1988 until October 2014 to gather eligible peer-reviewed papers addressing the prognostic effect of matrix metalloproteinase-7 in gastric cancer patients' survival. The CASP check list was used for quality appraisal. Pooled hazard ratio (HR) for survival and odds ratio (OR) for association with their 95% confidence interval (CI) were considered as summary measurements. Finally, 1208 gastric cancer patients from nine studies were included in the meta-analysis. Pooled HR estimate for survival was 2.01 (95% CI = 1.62 – 2.50, P < 0.001), which indicated a significant poor prognostic effect for matrix metalloproteinase-7. Sensitivity analysis detected no dominancy for any study. No publication bias was detected according to Egger’s and Begg’s tests. Clinicopathological assessment revealed that higher matrix metalloproteinase-7 expression is associated with deeper invasion (pooled OR = 3.20; 95% CI = 1.14 – 8.96; P = 0.026), higher TNM stage (pooled OR = 3.67; 95% CI = 2.281-5.99; P<0.001), lymph node metastasis (pooled OR = 2.84; 95% CI = 1.89 – 4.25; P<0.001), and distant metastasis (pooled OR = 3.68; 95% CI = 1.85 – 7.29; P<0.001), but not with histological grade. This meta-analysis indicated a significant poor prognostic effect of matrix metalloproteinase-7 in gastric cancer survival. Additionally it was associated with aggressive tumor phenotype.

Prognostic value of tissue inhibitor of metalloproteinase-2 expression in patients with non-small cell lung cancer: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Tissue inhibitor of metalloproteinase-2 (TIMP-2) is a small secretory glycoprotein with anti-matrix metalloproteinase activity. Data on the value of TIMP-2 as a prognostic factor in non-small cell lung cancer (NSCLC) are discordant and remain controversial. A systematic review and meta-analysis was performed to explore this issue.

METHODS

We identified the relevant literature by searching the PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure, SinoMed, and Wanfang Data databases (search terms: "non-small cell lung cancer" or "NSCLC" or "Lung Carcinoma, Non-Small-Cell", "Tissue Inhibitor of Metalloproteinase-2" or "TIMP-2", and "prognosis" or "prognostic" or "survive") for updates prior to March 1, 2014. The pooled hazard ratio (HR) of overall survival with a 95% confidence interval (95% CI) was used to evaluate the strength of the association between positive TIMP-2 expression and survival in patients with NSCLC.

RESULTS

We included 12 studies in our systematic review; five studies involving 399 patients with NSCLC were meta-analyzed. The pooled HR of all included patients was 0.57 (95% CI: 0.43-0.77), and the HRs of subgroup analysis according to stage (I-IV), testing method (immunohistochemistry) and high TIMP-2 expression percentage (<50%) were 0.63 (95% CI: 0.43-0.92), 0.55 (95% CI: 0.41-0.74), and 0.50 (95% CI: 0.28-0.88), respectively. These data suggested that high TIMP-2 expression is associated with favorable prognosis in NSCLC. The meta-analysis did not reveal heterogeneity or publication bias.

CONCLUSIONS

TIMP-2 expression indicates favorable prognosis in patients with NSCLC; as a protective factor, it could help predict outcome and may guide clinical therapy in the future.

SNAI2/SLUG and estrogen receptor mRNA expression are inversely correlated and prognostic of patient outcome in metastatic non-small cell lung cancer

Background

Epithelial-mesenchymal transition (EMT) is involved in important malignant features of cancer cells, like invasion, metastatic potential, anti-apoptotic and stem-cell like phenotypes. Among several transcription factors, SNAI2/SLUG is supposed to play an essential role for EMT.

Methods

Paraffin embedded tumor samples from 63 patients with metastatic non-small cell lung cancer, enrolled in a randomized phase II trial, were prospectively collected, 53 samples qualified for further analysis. Automated RNA extraction from paraffin and RT-quantitative PCR was used for evaluation of SNAI2/SLUG, estrogen receptor 1 (ESR1) and matrix-metalloproteinases (MMP) mRNA expression.

Results

Clinical features like age, gender, performance status, histological subtype and stage were similarly distributed among SNAI2/SLUG positive and negative patients. SNAI2/SLUG was significantly, inversely correlated with ESR1 mRNA expression (p < 0.0001). In contrast, MMP2 (p = 0.387), MMP7 (p = 0.396) and MMP9 mRNA expression (p = 0.366) did not correlate with SNAI2/SLUG. Patients with high SNAI2/SLUG expression (grouped by median expression) had a worse outcome. Median overall survival in patients with high SNAI2/SLUG expression was 5.7 months versus 11.6 months with low SNAI2/SLUG expression (p = .038). Inversely, patients with high ESR1 expression (grouped by median expression) had an improved median OS with 10.9 months vs. 5.0 months in the low expression group (p = .032). In multivariate analysis, SNAI2/SLUG2 (p = .022) and ESR1 (p = .017) separately were independent prognostic factors for survival.

Conclusion

SNAI2/SLUG is prognostic of patients’ outcome. The strong inverse correlation with ESR1 indicates a significant impact of estrogen receptor pathway regarding these malignant features.

PD-L1 over-expression and survival in patients with non-small cell lung cancer: a meta-analysis

BACKGROUND

Observational studies on the prognostic role of programmed cell death-ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) are controversial.

METHODS

To clarify the impact of PD-L1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios (HR) and their corresponding 95% confidence intervals (CIs) were calculated in terms of overall survival.

RESULTS

A total of five studies with 877 patients were evaluable for this meta-analysis. Our results suggested that PD-L1 overexpression had a poor impact on survival of patients with NSCLC, the HR (95% CI) was 1.43 (1.24-1.63) overall, 1.51 (1.24-1.7954) in Asian patients, 1.35 (1.08-1.63) in non-Asian patients. Moreover, there was no heterogeneity between the studies.

CONCLUSIONS

PD-L1 overexpression indicates a poor prognosis for patients with NSCLC.

Prognostic value of TTF-1 expression in patients with non-small cell lung cancer: A meta-analysis

BACKGROUND

Observational studies on the prognostic role of thyroid transcription factor 1 (TTF-1) in non-small-cell lung cancer (NSCLC) are controversial.

METHODS

To clarify the impact of TTF-1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios and their corresponding 95% confidence intervals were calculated in terms of overall survival.

RESULTS

A total of 17 studies with 2235 patients were evaluable for this meta-analysis. The studies were categorized by histology, disease stage and patient race. Our results suggested that TTF-1 overexpression had a favorable impact on survival of patients with NSCLC, the HR (95% CI) was 0.49 (0.42 to 0.55) overall, 0.46 (0.38-0.54) in Asian patients, 0.52 (0.42-0.63) in non-Asian patients, 0.45 (0.38-0.52) in adenocarcinoma, 0.63 (0.39-0.86) in stage I NSCLC, and 0.43 (0.33-0.53) in stage IIIb-IV NSCLC. The data collected were not sufficient to determine the prognostic value of VEGF in patients with squamous cell lung carcinomas. But there was a high heterogeneity between the studies.

CONCLUSION

TTF-1 overexpression indicates a favorable prognosis for patients with NSCLC, this effect appears also significant when the analysis is restricted in lung AC patients, stage I and stage IIIb-IV NSCLC.

Capn4 promotes non-small cell lung cancer progression via upregulation of matrix metalloproteinase 2

The expression of calpain small subunit 1 (Capn4) is correlated with the invasion of several types of tumors. However, the roles of Capn4 in non-small cell lung cancer (NSCLC) remain unclear. In this study, we found that the expression of Capn4 in NSCLC tissues was much higher than that in nontumorous samples. High levels of Capn4 expression were associated with lymph node metastasis and large tumor size in NSCLC patients. The 5-year overall survival rate in the Capn4(high) group was significantly lower than that in the Capn4(low) group. In multivariate analysis, Capn4 was identified as an independent prognostic factor for overall survival. Moreover, in an in vitro analysis, downregulation of Capn4 expression by siRNA suppressed the invasive potential of lung cancer cells. Finally, we demonstrated that Capn4 enhanced the invasion ability of lung cancer cells by upregulating the expression of matrix metalloproteinase 2. Our findings indicated that Capn4 may represent a potential therapeutic target and a novel prognostic marker of NSCLC.

Damnacanthal, a noni anthraquinone, inhibits c-Met and is a potent antitumor compound against Hep G2 human hepatocellular carcinoma cells

Damnacanthal, an anthraquinone present in noni plants, targets several tyrosine kinases and has antitumoral effects. This study aims at getting additional insight on the potential of damnacanthal as a natural antitumor compound. The direct effect of damnacanthal on c-Met was tested by in vitro activity assays. Additionally, Western blots of c-Met phosphorylation in human hepatocellular carcinoma Hep G2 cells were performed. The antitumor effects of damnacanthal were tested by using cell growth, soft agar clonogenic, migration and invasion assays. Their mechanisms were studied by Western blot, and cell cycle, apoptosis and zymographic assays. Results show that damnacanthal targets c-Met both in vitro and in cell culture. On the other hand, damnacanthal also decreases the phosphorylation levels of Akt and targets matrix metalloproteinase-2 secretion in Hep G2 cells. These molecular effects are accompanied by inhibition of the growth and clonogenic potential of Hep G2 hepatocellular carcinoma cells, as well as induction of Hep G2 apoptosis. Since c-Met has been identified as a new potential therapeutical target for personalized treatment of hepatocellular carcinoma, damnacanthal and noni extract supplements containing it could be potentially interesting for the treatment and/or chemoprevention of hepatocellular carcinoma through its inhibitory effects on the HGF/c-Met axis.

Melanoma expression of matrix metalloproteinase-23 is associated with blunted tumor immunity and poor responses to immunotherapy

BACKGROUND

Matrix metalloproteinase-23 (MMP-23) can block the voltage-gated potassium channel Kv1.3, whose function is important for sustained Ca(2+) signaling during T cell activation. MMP-23 may also alter T cell activity and phenotype through cleavage of proteins affecting cytokine and chemokine signaling. We therefore tested the hypothesis that MMP-23 can negatively regulate the anti-tumor T cell response in human melanoma.

METHODS

We characterized MMP-23 expression in primary melanoma patients who received adjuvant immunotherapy. We examined the association of MMP-23 with the anti-tumor immune response - as assessed by the prevalence of tumor-infiltrating lymphocytes and Foxp3(+) regulatory T cells. Further, we examined the association between MMP-23 expression and response to immunotherapy. Considering also an in trans mechanism, we examined the association of melanoma MMP-23 and melanoma Kv1.3 expression.

RESULTS

Our data revealed an inverse association between primary melanoma MMP-23 expression and the anti-tumor T cell response, as demonstrated by decreased tumor-infiltrating lymphocytes (TIL) (P = 0.05), in particular brisk TILs (P = 0.04), and a trend towards an increased proportion of immunosuppressive Foxp3(+) regulatory T cells (P = 0.07). High melanoma MMP-23 expression is also associated with recurrence in patients treated with immune biologics (P = 0.037) but not in those treated with vaccines (P = 0.64). Further, high melanoma MMP-23 expression is associated with shorter periods of progression-free survival for patients receiving immune biologics (P = 0.025). On the other hand, there is no relationship between melanoma MMP-23 and melanoma Kv1.3 expression (P = 0.27).

CONCLUSIONS

Our data support a role for MMP-23 as a potential immunosuppressive target in melanoma, as well as a possible biomarker for informing melanoma immunotherapies.

Targeting antitumor effect of rhTNF-α fusion protein mediated by matrix metalloproteinase-2

The aim of this study was to examine the tumor therapy, targeting effects and side effects of tumor-targeting rhTNF-α fusion protein mediated by matrix metalloproteinase-2 in an animal model in order to provide experimental data for future development of drugs. The median lethal dose (LD50) was obtained from acute toxicity experiments. The A549 lung cancer xenograft model was established, and then randomly divided into the saline, standard substance, and low-, middle- and high-dose fusion protein experiment groups. Each group was administered drugs for 18 days. The length and width of the xenografts were measured every three days, after which the xenograft growth curve was drawn. The mice were sacrificed in each group following treatment and the tumor volume and weight were measured. The targeting, effectiveness and toxicity of the transformed fusion protein, and pathological changes of tumor and organ tissues were examined by hematoxylin and eosin (H&E) staining. Additionally, biochemical markers were used to detect damage of various organs after protein processing. Cell apoptosis and angiogenesis were determined using terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL) testing and immunohistochemistry, respectively, in different dose groups. Tumor growth was markedly retarded in the high-dose experimental and standard hTNF-α groups with antitumor rates of 85.91 and 72.25%, respectively, as compared with the control group. Furthermore, the tumor tissue showed obvious apoptosis (the apoptotic index was 78.78 and 66.65%, respectively) and pathological changes in the high-dose experimental and standard hTNF-α groups. Tumor angiogenesis in each fusion protein group was inhibited (P<0.01) and the biochemical markers of various organs were greatly reduced in the high-dose experimental group (P<0.05). This finding indicated that slight toxic effects of fusion proteins were evident for the heart, liver and kidney. The reforming fusion protein can therefore target tumor tissues and efficiently kill tumor cells, with few side effects.