Platelet-type 12-lipoxygenase induces MMP9 expression and cellular invasion via activation of PI3K/Akt/NF-κB

Research progress on the role of lipoxygenase and its inhibitors in prostate cancer

Prostate cancer (PCa) has become a common disease among middle-aged and elderly men. The lipoxygenase (LOX) pathway plays a crucial role in the occurrence, development, invasion and metastasis of PCa and is therefore considered a new target for the prevention and treatment of PCa. 5-LOX and 12-LOX have a promoting effect on the occurrence, development, invasion and metastasis of PCa. 15-LOX-2 has an inhibitory effect on PCa. LOX inhibitors can effectively inhibit the metabolic activity of LOX. The research aims to review the mechanism of action and inhibitors of LOX in PCa, in order to provide relevant references for the prevention and treatment of PCa.

PI3K/AKT/mTORC1 signalling pathway regulates MMP9 gene activation via transcription factor NF-κB in mammary epithelial cells of dairy cows

Matrix metalloproteinase 9 (MMP9) plays a pivotal role in mammary ductal morphogenesis, angiogenesis and glandular tissue architecture remodeling. However, the molecular mechanism of MMP9 expression in mammary epithelial cells of dairy cows remains unclear. This study aimed to explore the underlying mechanism of MMP9 expression. In this study, to determine whether the PI3K/AKT/mTORC1/NF-κB signalling pathway participates in the regulation of MMP9 expression, we treated mammary epithelial cells with specific pharmacological inhibitors of PI3K (LY294002), mTORC1 (Rapamycin) or NF-κB (Celastrol), respectively. Western blotting results indicated that LY294002, Rapamycin and Celastrol markedly decreased MMP9 expression and P65 nuclear translocation. Furthermore, we found that NF-κB (P65) overexpression resulted in elevated expression of MMP9 protein and activation of MMP9 promoter. In addition, we observed that Celastrol markedly decreases P65-overexpression-induced MMP9 promoter activity. Moreover, the results of the promoter assay indicated that the core regulation sequence for MMP9 promoter activation may be located at -420 ∼ -80 bp downstream from the transcription start site. These observations indicated that the PI3K/AKT/mTORC1 signalling pathway is involved in MMP9 expression by regulating MMP9 promoter activity via NF-κB in the mammary epithelial cells of dairy cows.

PTEN-Long inhibits the biological behaviors of glioma cells

OBJECTIVES

PTEN-Long is a translational variant of phosphatase and tensin homolog (PTEN). This study aimed to assess the effect of PTEN-Long on the biological characteristics of glioma cells and related mechanisms.

METHODS

A vector stably expressing PTEN-Long was established and transfected into cells, serving as the overexpression group, while a set of empty vectors served as the negative control group. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and western blot were used to detect the expression of PTEN-Long and phosphatidylinositol 3-kinase, Protein kinase B, andnuclear factor-κB (PI3K-AKT-NF-κB). Cell proliferation was assessed with the Cell Counting Kit 8 (CCK8) assay, migration through the scratch test, and invasion by the transwell chamber assay. Cell cycle analysis was performed using flow cytometry. The volume and weight of subcutaneous tumors in nude mice were also evaluated.

RESULTS

PTEN-Long expression led to downregulation of p-Akt, NF-κB p65, p-NF-κB p65, and Bcl-xl, and up-regulation of IκBα. In addition, it inhibited glioma cell proliferation, induced cell cycle arrest in the G0/G1 phase, and reduced cell migration and invasion. Moreover, PTEN-Long inhibited the growth of subcutaneous glioma in nude mice.

CONCLUSIONS

PTEN-Long inhibits the proliferation, migration, and invasion and induces apoptosis in glioma cells by inhibiting PI3K-AKT-NF-κb signaling, implying that PTEN-Long may be a new target for glioma treatment.

Integrated network pharmacology and pharmacological investigations to explore the potential mechanism of Ding-Chuan-Tang against chronic obstructive pulmonary disease

ETHNOPHARMACOLOGICAL RELEVANCE

Ding-Chuan-Tang (Abbreviated as DCT) is frequently prescribed for treatment of respiratory diseases, including chronic obstructive pulmonary disease (COPD), which is characterized by coughing, wheezing, and chest tightness in traditional Chinese medicine (TCM). However, the potential mechanism of DCT has not been investigated.

AIM OF STUDY

The aim of the study is to explore the efficiency of DCT in the treatment of COPD in vivo and in vitro, and to illustrate the possible mechanism against COPD.

METHODS

COPD model was induced by exposure of mice to cigarette smoke (CS) for 16 weeks. Enzyme-linked immunosorbent assay (ELISA), immunofluorescence assay, Western blot, etc., were used to explore the efficiency and mechanisms of DCT. Network pharmacology analysis, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, etc., was performed to explore the potential targets in the treatment of DCT on COPD.

RESULTS

DCT significantly alleviated pulmonary pathological changes in mouse COPD model, and inhibited inflammatory response induced by CS and LPS in vivo and in vitro. Network pharmacology analysis suggested that DCT alleviated COPD via inhibiting inflammation by regulating PI3K-AKT pathway. In cell-based models, DCT suppressed the phosphorylation of PI3K and AKT, which further regulated its downstream targets Nrf2 and NF-κB, and inhibited inflammatory response.

CONCLUSIONS

DCT effectively attenuated COPD in the mouse model induced by CS. The therapeutic mechanism of DCT against COPD was closely associated with the regulation of PI3K-AKT pathway and its downstream transcription factors, Nrf2 and NF-κB.

DIAMMONIUM GLYCYRRHIZINATE INHIBITED INFLAMMATORY RESPONSE AND MODULATED SERUM METABOLISM IN POLY(I:C)-INDUCED PNEUMONIA MODEL MICE

ABSTRACT

Currently, the coronavirus disease 2019 (COVID-19) is becoming a serious threat to human health worldwide. Therefore, there is a great need to develop effective drugs against viral pneumonia. Diammonium glycyrrhizinate (DG), derived from Glycyrrhiza glabra L., has been demonstrated with significant anti-inflammatory properties. However, the therapeutic effects and mechanisms of DG on pneumonia require further clarification. In this study, mice received intratracheal injection of polyinosinic-polycytidylic acid (poly(I:C)) to induce pneumonia and were treated with DG. First, we evaluated the therapeutic potential of DG on poly(I:C)-induced pneumonia. Second, the anti-inflammatory and antioxidative activities and the impact of DG on the toll-like receptor 3 (TLR3) pathway were investigated. Third, the mechanism of DG was analyzed through untargeted metabolomics techniques. Our results revealed that DG intervention decreased permeability and reduced abnormal lung alterations in poly(I:C)-induced pneumonia model mice. DG intervention also downregulated cytokine levels in bronchoalveolar lavage fluid. Moreover, DG treatment inhibited the activation of TLR3 pathway. Furthermore, untargeted metabolomics analysis revealed that DG intervention could modulate serum metabolites involved in amino and nucleotide sugar metabolism, fructose and mannose metabolism, tyrosine metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis pathways. In conclusion, our study showed that DG could ameliorate poly(I:C)-induced pneumonia by inactivating the TLR3 pathway and affecting amino and nucleotide sugar, fructose and mannose metabolism, as well as tryptophan, phenylalanine, and tyrosine biosynthesis.

The TRPM4 channel inhibitor 9-phenanthrol alleviates cerebral edema after traumatic brain injury in rats

Cerebral edema (CE) exerts an important effect on brain injury after traumatic brain injury (TBI). Upregulation of transient receptor potential melastatin 4 (TRPM4) in vascular endothelial cells (ECs) results in damage to capillaries and the blood-brain barrier (BBB), which is critical for the development of CE. Many studies have shown that 9-phenanthrol (9-PH) effectively inhibits TRPM4. The current study aimed to investigate the effect of 9-PH on reducing CE after TBI. In this experiment, we observed that 9-PH markedly reduced brain water content, BBB disruption, proliferation of microglia and astrocytes, neutrophil infiltration, neuronal apoptosis and neurobehavioral deficits. At the molecular level, 9-PH significantly inhibited the protein expression of TRPM4 and MMP-9, alleviated the expression of apoptosis-related molecules and inflammatory cytokines, such as Bax, TNF-α and IL-6, near injured tissue, and diminished serum SUR1 and TRPM4 levels. Mechanistically, treatment with 9-PH inhibited activation of the PI3K/AKT/NF-kB signaling pathway, which was reported to be involved in the expression of MMP-9. Taken together, the results of this study indicate that 9-PH effectively reduces CE and alleviates secondary brain injury partly through the following possible mechanisms: ①9-PH inhibits TRPM4-mediated Na + influx and reduces cytotoxic CE; ②9-PH hinders the expression and activity of MMP-9 by inhibiting the TRPM4 channel and decreases disruption of the BBB, thereby preventing vasogenic cerebral edema. ③9-PH reduces further inflammatory and apoptotic damage to tissues.

Biology and pharmacology of platelet-type 12-lipoxygenase in platelets, cancer cells, and their crosstalk

Platelet-type lipoxygenase (pl12-LOX), encoded by ALOX12, catalyzes the production of the lipid mediator 12S-hydroperoxyeicosa-5,8,10,14-tetraenoic acid (12S-HpETE), which is quickly reduced by cellular peroxidases to form 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid (12S-HETE). Platelets express high levels of pl12-LOX and generate considerable amounts of 12S-HETE from arachidonic acid (AA; C20:4, n-6). The development of sensitive chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods has allowed the accurate quantification of 12S-HETE in biological samples. Moreover, advances in the knowledge of the mechanism of action of 12S-HETE have been achieved. The orphan G-protein-coupled receptor 31 (GPR31) has been identified as the high-affinity 12S-HETE receptor. Moreover, upon platelet activation, 12S-HETE is produced, and significant amounts are found esterified to membrane phospholipids (PLs), such as phosphatidylethanolamine (PE) and phosphatidylcholine (PC), promoting thrombin generation. Platelets play many roles in cancer metastasis. Among them, the platelets' ability to interact with cancer cells and transfer platelet molecules by the release of extracellular vesicles (EVs) is noteworthy. Recently, it was found that platelets induce epithelial-mesenchymal transition(EMT) in cancer cells, a phenomenon known to confer high-grade malignancy, through the transfer of pl12-LOX contained in platelet-derived EVs. These cancer cells now generate 12-HETE, considered a key modulator of cancer metastasis. Interestingly, 12-HETE was mainly found esterified in plasmalogen phospholipids of cancer cells. This review summarizes the current knowledge on the regulation and functions of pl12-LOX in platelets and cancer cells and their crosstalk.Novel approaches to preventing cancer and metastasis by the pharmacological inhibition of pl12-LOX and the internalization of mEVs are discussed.

lncRNA MEG3 Inhibits the Proliferation and Growth of Glioma Cells by Downregulating Bcl-xL in the PI3K/Akt/NF-κB Signal Pathway

This study was conducted to investigate the impact and mechanisms of lncRNA MEG3 on glioma cells. lncRNA MEG3 was lowly expressed in glioma cells as compared to noncancer cells. Overexpression of MEG3 significantly downregulated the expression of Bcl-xL, slightly upregulated the expression of NF-κB p65 and IκBα, and reduced the proliferation of glioma cells with increased apoptosis and the migration and invasion ability. Subsequently, glioma cells overexpressing MEG3 had less tumorgenicity in xenograft mouse models. It is likely that MEG3 induces apoptosis in glioma cells via downregulating the Bcl-xL gene in the PI3K/Akt/NF-κB signal pathway to reduce the development of glioma.

Extracellular vesicles in β cell biology: Role of lipids in vesicle biogenesis, cargo, and intercellular signaling

BACKGROUND

Type 1 diabetes (T1D) is a complex autoimmune disorder whose pathogenesis involves an intricate interplay between β cells of the pancreatic islet, other islet cells, and cells of the immune system. Direct intercellular communication within the islet occurs via cell surface proteins and indirect intercellular communication has traditionally been seen as occurring via secreted proteins (e.g., endocrine hormones and cytokines). However, recent literature suggests that extracellular vesicles (EVs) secreted by β cells constitute an additional and biologically important mechanism for transmitting signals to within the islet.

SCOPE OF REVIEW

This review summarizes the general mechanisms of EV formation, with a particular focus on how lipids and lipid signaling pathways influence their formation and cargo. We review the implications of EV release from β cells for T1D pathogenesis, how EVs and their cargo might be leveraged as biomarkers of this process, and how EVs might be engineered as a therapeutic candidate to counter T1D outcomes.

MAJOR CONCLUSIONS

Islet β cells have been viewed as initiators and propagators of the cellular circuit giving rise to autoimmunity in T1D. In this context, emerging literature suggests that EVs may represent a conduit for communication that holds more comprehensive messaging about the β cells from which they arise. As the field of EV biology advances, it opens the possibility that intervening with EV formation and cargo loading could be a novel disease-modifying approach in T1D.

Inflammation and Cancer: From the Development of Personalized Indicators to Novel Therapeutic Strategies

Colorectal (CRC) and hepatocellular carcinoma (HCC) are associated with chronic inflammation, which plays a role in tumor development and malignant progression. An unmet medical need in these settings is the availability of sensitive and specific noninvasive biomarkers. Their use will allow surveillance of high-risk populations, early detection, and monitoring of disease progression. Moreover, the characterization of specific fingerprints of patients with nonalcoholic fatty liver disease (NAFLD) without or with nonalcoholic steatohepatitis (NASH) at the early stages of liver fibrosis is necessary. Some lines of evidence show the contribution of platelets to intestinal and liver inflammation. Thus, low-dose Aspirin, an antiplatelet agent, reduces CRC and liver cancer incidence and mortality. Aspirin also produces antifibrotic effects in NAFLD. Activated platelets can trigger chronic inflammation and tissue fibrosis via the release of soluble mediators, such as thromboxane (TX) A2 and tumor growth factor (TGF)-β, and vesicles containing genetic material (including microRNA). These platelet-derived products contribute to cyclooxygenase (COX)-2 expression and prostaglandin (PG)E2 biosynthesis by tumor microenvironment cells, such as immune and endothelial cells and fibroblasts, alongside cancer cells. Enhanced COX-2-dependent PGE2 plays a crucial role in chronic inflammation and promotes tumor progression, angiogenesis, and metastasis. Antiplatelet agents can indirectly prevent the induction of COX-2 in target cells by inhibiting platelet activation. Differently, selective COX-2 inhibitors (coxibs) block the activity of COX-2 expressed in the tumor microenvironment and cancer cells. However, coxib chemopreventive effects are hampered by the interference with cardiovascular homeostasis via the coincident inhibition of vascular COX-2-dependent prostacyclin biosynthesis, resulting in enhanced risk of atherothrombosis. A strategy to improve anti-inflammatory agents' use in cancer prevention could be to develop tissue-specific drug delivery systems. Platelet ability to interact with tumor cells and transfer their molecular cargo can be employed to design platelet-mediated drug delivery systems to enhance the efficacy and reduce toxicity associated with anti-inflammatory agents in these settings. Another peculiarity of platelets is their capability to uptake proteins and transcripts from the circulation. Thus, cancer patient platelets show specific proteomic and transcriptomic expression profiles that could be used as biomarkers for early cancer detection and disease monitoring.

Molecular Mechanisms and Clinical Challenges of Glioma Invasion

Glioma is the most common primary brain tumor, and its prognosis is poor. Glioma cells are highly invasive to the brain parenchyma. It is difficult to achieve complete resection due to the nature of the brain tissue, and tumors that invade the parenchyma often recur. The invasiveness of tumor cells has been studied from various aspects, and the related molecular mechanisms are gradually becoming clear. Cell adhesion factors and extracellular matrix factors have a strong influence on glioma invasion. The molecular mechanisms that enhance the invasiveness of glioma stem cells, which have been investigated in recent years, have also been clarified. In addition, it has been discussed from both basic and clinical perspectives that current therapies can alter the invasiveness of tumors, and there is a need to develop therapeutic approaches to glioma invasion in the future. In this review, we will summarize the factors that influence the invasiveness of glioma based on the environment of tumor cells and tissues, and describe the impact of the treatment of glioma on invasion in terms of molecular biology, and the novel therapies for invasion that are currently being developed.

Validating Cell Surface Proteases as Drug Targets for Cancer Therapy: What Do We Know, and Where Do We Go?

Cell surface proteases (also known as ectoproteases) are transmembrane and membrane-bound enzymes involved in various physiological and pathological processes. Several members, most notably dipeptidyl peptidase 4 (DPP4/CD26) and its related family member fibroblast activation protein (FAP), aminopeptidase N (APN/CD13), a disintegrin and metalloprotease 17 (ADAM17/TACE), and matrix metalloproteinases (MMPs) MMP2 and MMP9, are often overexpressed in cancers and have been associated with tumour dysfunction. With multifaceted actions, these ectoproteases have been validated as therapeutic targets for cancer. Numerous inhibitors have been developed to target these enzymes, attempting to control their enzymatic activity. Even though clinical trials with these compounds did not show the expected results in most cases, the field of ectoprotease inhibitors is growing. This review summarizes the current knowledge on this subject and highlights the recent development of more effective and selective drugs targeting ectoproteases among which small molecular weight inhibitors, peptide conjugates, prodrugs, or monoclonal antibodies (mAbs) and derivatives. These promising avenues have the potential to deliver novel therapeutic strategies in the treatment of cancers.

Evaluation of the anti-inflammatory and antioxidant pharmcodynamic compoents of naoxintong capsules as a basis of broad spectrum effects

CONTEXT

Naoxintong capsule (NXT) is one of the most prevalent Traditional Chinese Medicine formulations in the treatment of coronary heart disease (CHD), yet the action of pharmacodynamic components remains unclear.

OBJECTIVE

To determine the basis by which pharmacodynamic components of NXT may be effective in the treatment of CHD.

MATERIALS AND METHODS

The protective effect of NXT (0.01-100 μg/mL) on 293 T and hy926 cells was determined by MTT assay for 24 h. Afterwards, to investigate the pharmacodynamic material basis of NXT in anti-inflammatory and antioxidant effects, based on previous UPLC/Q-TOF analysis, 293 T and hy926 cells were divided into control (treated with solvent), model (incubated with TNF-α, LPS or H₂O₂), intervention (treated with UPLC components) and positive groups. After 24 h of treatment, all cells were tested to verify the screening results. MOE software was applied to dock bioactive compounds with phosphoinositide 3-kinase (PI3K), then the protein expression and phosphate levels were determined by western blotting.

RESULTS

NXT could significantly inhibit the expression of NF-κB, MMP-9 and NO in cells with IC₅₀ values of 0.1178, 0.1182 and 0.1094 μg/mL. Based on the screening results, six components of NXT were identified (calycosin, ferulic acid, salvianolic acid B, ononin, salvianolic acid E, and salvianolic acid F) which can inhibit NF-κB, MMP-9, and NO simultaneously, while exerting cytoprotective effects by inhibiting the activation of the PI3K/AKT pathway under different conditions by virtue of their advantageous interaction with PI3K.

CONCLUSIONS

These ingredients have outstanding therapeutic potential and may provide a scientific basis for the future application and research of NXT.

Lipopeptide Pepducins as Therapeutic Agents

Pepducins are lipidated peptides that target the intracellular loops of G protein-coupled receptors (GPCRs) in order to modulate transmembrane signaling to internally located effectors. With a wide array of potential activities ranging from partial, biased, or full agonism to antagonism, pepducins represent a versatile class of compounds that can be used to potentially treat diverse human diseases or be employed as novel tools to probe complex mechanisms of receptor activation and signaling in cells and in animals. Here, we describe a number of different pepducins including an advanced compound, PZ-128, that has successfully progressed through phase 2 clinical trials in cardiac patients demonstrating safety and efficacy in suppressing myonecrosis and arterial thrombosis.

Hexokinases 2 promoted cell motility and distant metastasis by elevating fibronectin through Akt1/p-Akt1 in cervical cancer cells

Background

Hexokinases 2 (HK2) is a member of the hexokinases, linking with malignant tumor growth and distant metastasis. However, evidence regarding the potential role of HK2 in regulating cell motility and tumor metastasis during the cervical cancer malignant progression remains limited.

Methods

In vitro migration and invasion assay, in vivo metastasis experiments were performed to detect the effective of HK2 on regulating cell motility and tumor metastasis in cervical cancer cells. RNA-Seq was performed to explore the potential molecules that participate in HK2-mediated cell motility and tumor metastasis in cervical cancer cells. The correlation between HK2 and Akt1, p-Akt1, FN1 expression in cervical cancer cells and human squamous cervical carcinoma (SCC) samples was verified in this study.

Results

In this study, cervical cancer cells with exogenous HK2 expression exhibited enhanced cell motility and distant metastasis. Transcriptome sequencing analysis revealed that fibronectin (FN1) was significantly increased in HK2-overexpressing HeLa cells, and the PI3K/Akt signaling pathway was identified by KEGG pathway enrichment analysis. Further studies demonstrated that this promotion of cell motility by HK2 was probably a result of it inducing FN1, MMP2 and MMP9 expression by activating Akt1 in cervical cancer cells. Additionally, HK2 expression was altered with the changing of Akt1/p-Akt1 expression, implying that HK2 expression is also modulated by Akt1/p-Akt1. Moreover, the positive correlation between HK2 and Akt1, p-Akt1, FN1 expression in human squamous cervical carcinoma (SCC) samples was verified by using Pearson correlation analysis.

Conclusions

This study demonstrated that HK2 could activate Akt1 in cervical cancer cells, subsequently enhancing cell motility and tumor metastasis by inducing FN1, MMP2 and MMP9 expression. There likely exists an interactive regulatory mechanism between HK2 and Akt1 during the malignant process of cervical cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02312-0.

Reveals of candidate active ingredients in Justicia and its anti-thrombotic action of mechanism based on network pharmacology approach and experimental validation

Thrombotic diseases seriously threaten human life. Justicia, as a common Chinese medicine, is usually used for anti-inflammatory treatment, and further studies have found that it has an inhibitory effect on platelet aggregation. Therefore, it can be inferred that Justicia can be used as a therapeutic drug for thrombosis. This work aims to reveal the pharmacological mechanism of the anti-thrombotic effect of Justicia through network pharmacology combined with wet experimental verification. During the analysis, 461 compound targets were predicted from various databases and 881 thrombus-related targets were collected. Then, herb-compound-target network and protein-protein interaction network of disease and prediction targets were constructed and cluster analysis was applied to further explore the connection between the targets. In addition, Gene Ontology (GO) and pathway (KEGG) enrichment were used to further determine the association between target proteins and diseases. Finally, the expression of hub target proteins of the core component and the anti-thrombotic effect of Justicia's core compounds were verified by experiments. In conclusion, the core bioactive components, especially justicidin D, can reduce thrombosis by regulating F2, MMP9, CXCL12, MET, RAC1, PDE5A, and ABCB1. The combination of network pharmacology and the experimental research strategies proposed in this paper provides a comprehensive method for systematically exploring the therapeutic mechanism of multi-component medicine.

Platelets induce free and phospholipid-esterified 12-hydroxyeicosatetraenoic acid generation in colon cancer cells by delivering 12-lipoxygenase

Platelets promote tumor metastasis by inducing promalignant phenotypes in cancer cells and directly contributing to cancer-related thrombotic complications. Platelet-derived extracellular vesicles (EVs) can promote epithelial-mesenchymal transition (EMT) in cancer cells, which confers high-grade malignancy. 12S-hydroxyeicosatetraenoic acid (12-HETE) generated by platelet-type 12-lipoxygenase (12-LOX) is considered a key modulator of cancer metastasis through unknown mechanisms. In platelets, 12-HETE can be esterified into plasma membrane phospholipids (PLs), which drive thrombosis. Using cocultures of human platelets and human colon adenocarcinoma cells (line HT29) and LC-MS/MS, we investigated the impact of platelets on cancer cell biosynthesis of 12S-HETE and its esterification into PLs and whether platelet ability to transfer its molecular cargo might play a role. To this aim, we performed coculture experiments with CFSE[5-(and-6)-carboxyfluorescein diacetate, succinimidyl ester]-loaded platelets. HT29 cells did not generate 12S-HETE or express 12-LOX. However, they acquired the capacity to produce 12S-HETE mainly esterified in plasmalogen phospholipid forms following the uptake of platelet-derived medium-sized EVs (mEVs) expressing 12-LOX. 12-LOX was detected in plasma mEV of patients with adenomas/adenocarcinomas, implying their potential to deliver the protein to cancer cells in vivo. In cancer cells exposed to platelets, endogenous but not exogenous 12S-HETE contributed to changes in EMT gene expression, mitigated by three structurally unrelated 12-LOX inhibitors. In conclusion, we showed that platelets induce the generation of primarily esterified 12-HETE in colon cancer cells following mEV-mediated delivery of 12-LOX. The modification of cancer cell phospholipids by 12-HETE may functionally impact cancer cell biology and represent a novel target for anticancer agent development.

RAD001 targeted HUVECs reverses 12-lipoxygenase-induced angiogenesis in oesophageal squamous cell carcinoma

12‐LOX plays an important role in the progression of various malignancies. However, the underlying mechanisms of the action of 12‐LOX and tumour treatment strategies remain not fully defined. In this study, we investigated the possible roles of 12‐LOX in ESCC and explored the new therapeutic target. Approximately 73% of ESCC tissues showed marked up‐regulation of 12‐LOX, which was associated with poor prognosis. 12‐LOX overexpression was positively correlated with the malignant progression of ESCC as demonstrated both in vitro and in vivo. Up‐regulation of 12‐LOX significantly increased the proliferation of ESCC cells and the xenograft volume. Moreover, 12‐LOX up‐regulation promoted tube formation of HUVECs and tumour angiogenesis in xenografts. Mechanism investigation indicated that 12‐LOX overexpression led to activation of the PI3K/AKT/mTOR pathway and the up‐regulation of VEGF in ESCC cells. Subsequent analysis indicated that the RAD001 could reverse the 12‐LOX‐induced promoting effect on ESCC. Specifically, the application of RAD001 inhibited the proliferation of ESCC cells and the tube‐forming ability of HUVECs. In the drug group, the xenografts exhibited significant volume reduction and angiogenesis inhibition. We demonstrated that RAD001 could inhibit HUVEC migration. These findings presented the evidence that RAD001 had distinct roles on HUVECs and could exert anti‐tumour effects by targeting not only the PI3K/AKT/mTOR pathway but the angiogenesis in ESCC.

Prediction of the Therapeutic Effects of Pembrolizumab and Nivolumab in Advanced Non-Small Cell Lung Cancer by Platelet-Derived Microparticles in Circulating Blood

BACKGROUND

There are limited methods to predict the therapeutic effect of immune checkpoint inhibitors (ICIs). The purpose of this study was to explore the value of circulating microparticles (MPs) in predicting thetherapeutic effects of immunotherapy.

METHODS

A prospective study was conducted at the cancer center of PLA general hospital, including all patients with advanced non-small cell lung cancer (NSCLC) who were treated with pembrolizumab or nivolumab from December 2018 to December 2019. The patients were divided into an immune-related objective response (iOR) group and an immune-related disease progression (iPD) group.The numbers of total MPs, platelet-derived microparticles (PMPs) and T-lymphocyte-derived microparticles (T-LyMPs) at baseline and after immunotherapy were detected using a flow cytometer. Univariate analysis and multivariate logistic regression analysis were used to determine the independent influencing factors.

RESULTS

We identified 32 patients in the iOR group and 18 patients in the iPD group. No significant difference were found intotal MPs, PMPs and T-LyMPs at the baseline between the 2 groups. While total MPs, PMPs and T-LyMPs in the iPD group were significantly higher than those in the iOR group after immunotherapy(P < 0.05). In the multivariate logistic regression analysis, PMPs ≥80 events/µL after immunotherapy(OR, 7.270; 95% CI, 1.092-48.404, P = 0.04) were associated with disease progression in advanced NSCLC and could independently predict the therapeutic effect of immunotherapy.

CONCLUSIONS

PMPs after immunotherapy independently predicted the therapeutic effects of ICIs, making it possible to monitor the therapeutic effect in real time and rapidly adjust treatment regimens. In addition, this study found for the first time that elevated circulating T-LyMPs were associated with disease progression in advanced NSCLC.

Inhibition of PI3K/Akt/NF-κB signaling by Aloin for ameliorating the progression of osteoarthritis: In vitro and in vivo studies

Osteoarthritis (OA) is a progressive and degenerative joint disease. Aloin is a bitter and yellow-brown-coloured compound from the Aloe plant and is allowed for use in foods as a "natural flavour". In our study, we examined the protective effects of Aloin on the inhibition of OA development as well as its underlying mechanism in both in vitro and vivo experiments. In in-vitro experiments, the protective effect of aloin on the anabolism and catabolism of the extracellular matrix (ECM) induced by IL-1 β in chondrocytes by inhibiting the expression of pro-inflammatory factors, including TNF-α (p = 0.016), IL-6 (p = 0.006), iNOS (p = 0.001) and COX-2 (p = 0.006). Mechanistically, Aloin suppressed the IL-1β-induced activation of the PI3K/Akt/NF-κB signalling pathway cascades. Moreover, molecular docking studies demonstrated that Aloin bound strongly to PI3K. In vivo, Aloin ameliorated the OA process in the destabilization of the medial meniscus (DMM) model. In summary, our findings demonstrate that Aloin ameliorates the progression of OA via the PI3K/Akt/NF-κB signalling pathways, which supports Aloin as a promising therapeutic agent for the treatment of OA.

Radiotherapy Increases 12-LOX and CCL5 Levels in Esophageal Cancer Cells and Promotes Cancer Metastasis via THP-1-Derived Macrophages

BACKGROUND

Dioxygenase 12-lipoxygenase (12-LOX) plays an important role in tumorigenesis and promotes angiogenesis and proliferation in several tumors, including prostate and breast tumors. Radiotherapy enhances the expression of 12-LOX in esophageal squamous cell carcinoma (ESCC). Two types of macrophages can be found in the tumor microenvironment. The M2 subtype accelerates tumor progression; however, the relationship between 12-LOX and macrophages is not well established. Here, we explore this interaction and its effect on ESCC to induce tumor progression.

METHODS AND RESULTS

RT-qPCR and Western blot analyses were used to evaluate the mRNA and protein expression levels of 12-LOX and chemokine (C-C motif) ligand 5 (CCL5) in ESCC after radiotherapy. CCL5 expression was increased by 12-LOX upregulation but was suppressed by the well-established 12-LOX inhibitor, baicalein. Furthermore, CCL5 attracted and repolarized human myeloid leukemia mononuclear cells (THP-1)-derived macrophages. Finally, ESCC co-culture with THP-1-derived macrophages led to a strong cancer migratory capacity.

CONCLUSION

Radiation-induced 12-LOX overexpression in ESCC upregulates CCL5 expression, thereby attracting THP-1-derived macrophages and promoting their polarization to the M2 subtype, which enhances cellular metastasis.

Huoxuezhitong capsule ameliorates MIA-induced osteoarthritis of rats through suppressing PI3K/ Akt/ NF-κB pathway

Huoxuezhitong capsule (HXZT, activating blood circulation and relieving pain capsule), has been applied for osteoarthritis since 1974. It consists of Angelica sinensis (Oliv.) Diels, Panax notoginseng (Burkill) F. H. Chen ex C. H., Boswellia sacra, Borneol, Eupolyphaga sinensis Walker, Pyritum. However, the direct effects of HXZT on osteoarthritis and the underlying mechanisms were poorly understood. In this study, we aimed to explore the analgesia effect of HXZT on MIA-induced osteoarthritis rat and the underlying mechanisms. The analgesia and anti-inflammatory effect of HXZT on osteoarthritis in vivo were tested by the arthritis model rats induced by monosodium iodoacetate (MIA).. Mechanistic studies confirmed that HXZT could inhibit the activation of NF-κB and down-regulate the mRNA expression of related inflammatory factors in LPS-induced RAW264.7 and ATDC5 cells. Furtherly, in LPS-induced RAW264.7 cells, HXZT could suppress NF-κB via inhibiting PI3K/Akt pathway. Taken together, HXZT capsule could ameliorate MIA-induced osteoarthritis of rats through suppressing PI3K/ Akt/ NF-κB pathway.

HER4 promotes the growth and metastasis of osteosarcoma via the PI3K/AKT pathway

Osteosarcoma is the most common primary malignant bone tumor, which occurs in adolescents. As reported by our previous studies, HER4 indicates a poor prognosis of primary osteosarcoma. However, its mechanisms in the pathogenesis of osteosarcoma have not yet been studied. The purpose of this study was to investigate the role of HER4 in osteosarcoma and whether the PI3K/AKT pathway is involved. In this study, western blot analysis was used to investigate the expression of HER4 protein in osteosarcoma tissues and cell lines. CCK8 and transwell assays were used to detect the effects of HER4 on the proliferation, migration, and invasion of osteosarcoma cells in vitro. The effects of HER4 on the growth and metastasis of osteosarcoma in vivo were detected by tumor formation and immunofluorescence in nude mice. The role of the PI3K/AKT pathway in HER4 regulation of the growth and metastasis of osteosarcoma was examined by western blot analysis and immunofluorescence assay. We found that HER4 protein was highly expressed in clinical osteosarcoma specimens and osteosarcoma cells. HER4 markedly promoted the proliferation, migration, and invasion of osteosarcoma cells in vitro as well as the growth and metastasis of osteosarcoma in vivo. HER4 overexpression upregulated the expression of phosphorylated protein kinase B (pAKT), proliferation marker antigen Ki67, and metastasis cell marker matrix metalloproteinase 9 (MMP9). Notably, PI3K/AKT inhibitor LY294002 significantly inhibited the effects of HER4 via the downregulation of pAKT, Ki67, and MMP9. Moreover, LY294002 markedly blocked the effects of HER4-induced upregulation of tumor malignancy. The present study suggests that HER4 may promote the growth and metastasis of osteosarcoma via the PI3K/AKT pathway. The HER4/PI3K/AKT pathway could serve as a potential target for the treatment of osteosarcoma.

12-lipoxygenase promotes tumor progress by TGF-β1-mediated epithelial to mesenchymal transition and predicts poor prognosis in esophageal squamous cell carcinoma

Purpose

To clarify the effect of 12-lipoxygenase/12-hydroxyeicosatetraeonic acid (12-LOX/12-HETE) on progress of esophageal squamous cell carcinoma (ESCC) and the possible mechanism.

Patients and methods

We performed cell experiments including chemical treatment, transfection, Western blotting and transwell assay to investigate the function of 12-LOX/12-HETE. Slices of tumor tissues were obtained from ESCC patients treated in Qilu Hospital of Shandong University. Immunohistochemical (IHC) staining was done to find their correlation with prognosis and clinicopathological characteristics.

Results

In ESCC cells, inhibition of 12-LOX caused a decrease in transforming growth factor-β1 (TGF-β1)-mediated epithelial-mesenchymal transition (EMT) level, and abilities of migration and invasion were also inhibited. Nevertheless, the inhibition could be partly relieved when treated with 12-HETE or TGF-β1. Analyses of IHC staining indicated a positive correlation between the expression of 12-LOX and EMT level, and an inverse correlation between 12-LOX and overall survival (OS). Univariate and multivariate analyses further suggested that 12-LOX was an independent prognostic factor for ESCC patients.

Conclusion

In conclusion, our study proved that 12-LOX/12-HETE-promoted tumor migration and invasion might partly be through TGF-β1-mediated EMT in ESCC, and 12-LOX could be a promising biomarker for predicting prognosis in ESCC patients.

12-Lipoxygenase promotes epithelial-mesenchymal transition via the Wnt/β-catenin signaling pathway in gastric cancer cells

Background

12-Lipoxygenase (12-LOX) plays a major role in the progression and metastasis of various types of cancer. In gastric cancer (GC), the expression level of 12-LOX is significantly up-regulated; however, its function, and underlying mechanism of action remain unclear.

Methods

The mRNA and protein expression levels of 12-LOX were assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analyses, respectively, in GC cell lines. 12-LOX expression was stably up-regulated using lentiviral vector in BGC823 and MGC803 cells, and cell-counting kit-8 (CCK8), colony formation, and invasion assays were performed to verify the function of 12-LOX in proliferation and metastasis. In addition, the expression levels of epithelial-mesenchymal transition (EMT) differentiation markers and downstream targets of the Wnt/β-catenin signaling pathway were examined by Western blotting. A nude mouse model of tumor growth and metastasis was established to investigate the role of 12-LOX in vivo.

Results

Our findings demonstrate that 12-LOX mRNA and protein were highly expressed in GC cell lines. 12-LOX overexpression promoted GC cell proliferation, migration, and invasion both in vitro and in vivo. In addition, up-regulation of 12-LOX promoted the EMT in GC cells, as reflected by a decrease in E-cadherin expression and an increase in N-cadherin and Snail expression. 12-LOX overexpression in GC cells also increased the expression of multiple downstream targets of the Wnt/β-catenin signaling pathway.

Conclusion

These findings revealed that 12-LOX functions as an oncogene in promoting GC cell proliferation and metastasis in vitro and in vivo. In addition, 12-LOX might regulate the EMT via the Wnt/β-catenin signaling pathway, indicating a potential role for 12-LOX as a target in GC treatment.

MMP-9 secreted by tumor associated macrophages promoted gastric cancer metastasis through a PI3K/AKT/Snail pathway

PURPOSE

The distant metastasis in gastric has become an obstacle for treatment in clinic. However, the underlying mechanism is not well illustrated. Here, our aim is to reveal the mechanism and try to explore the potential strategy to overcome the distant metastasis.

MATERIALS AND METHODS

IHC was used to detect the expressions of target proteins. H&E staining was used to evaluate the lung metastasis. Using qRT-PCR and ELISA, we detected the expression of target genes and secreted proteins. Western bolt was used to examine the target proteins expression. Wound healing and transwell assay were used to examine the ability of cell to invasion and migration. Using IF, PI3K/AKT/Snail was examined. Animal models were applied to evaluate the killing efficiency in vivo.

RESULTS

Here, we observed accumulated CD68 (a marker of TAMs) in samples from gastric cancer patients with metastasis compared with that in samples from non-metastasis patients. And the expression of CD68 was negatively correlated with patients' survival time. Then, we found that TAMs enhanced the ability of cancer cells to migration and invasion in vitro and in vivo. Further, we revealed that the distant metastasis was induced by TAMs through secreting MMP-9, which induced epithelial to mesenchymal transition (EMT) process through the transcription factor Snail. Further, applying proenzyme inhibitor of MMP-9 significantly enhanced the killing efficiency of chemotherapeutic drugs and reduced the lung metastasis.

CONCLUSION

Our data showed that TAMs facilitate the EMT process via an MMP-9/PI3K/AKT/Snail dependent pathway, while blocking this signaling pathway with MMP-9 proenzyme inhibitor could suppress distant metastasis in gastric cancer.

The role of the 12(S)-HETE/GPR31/12-HETER axis in cancer and ischemia-reperfusion injury

The G protein-coupled receptors (GPCRs) constitute a large superfamily of seven transmembrane-spanning receptors that are activated by several classes of ligands, including bioactive lipids. GPCRs are attractive therapeutic targets for the treatment of human diseases, as they finely regulate a wide array of cellular functions. In this minireview, we summarized what is currently known about the G protein-coupled receptor GPR31/12-HETER. We highlighted, in particular, its structural similarity with human homologs, the biological functions of its recognized ligand 12(S)-hydroxyeicosatetraenoic acid (HETE), an arachidonic acid metabolite, and the role that GPR31/12-HETER-mediated signals play in cancer cell growth, invasion and metastasis, and in liver ischemia-reperfusion (IR) injury. Recent studies shed light and interest on the 12(S)-HETE/GPR31/12-HETER-activated signaling pathways and functions. The full spectrum of GPR31/12-HETER-mediated biological functions has yet to be characterized. Further studies are needed to identify other potential ligands, i.e. other than 12(S)-HETE. Another important remaining question is whether the multiple 12(S)-HETE-induced biological activities, including its role in diabetes, neurodegeneration, neuroprotection, and platelet function, occur via GPR31/12-HETER and/or involve the activation of other receptor molecules and pathways.

Oleic acid induces migration through a FFAR1/4, EGFR and AKT-dependent pathway in breast cancer cells

Free fatty acids (FFAs) are an energy source, and induce activation of signal transduction pathways that mediate several biological processes. In breast cancer cells, oleic acid (OA) induces proliferation, matrix metalloproteinase-9 (MMP-9) secretion, migration and invasion. However, the signal transduction pathways that mediate migration and invasion induced by OA in breast cancer cells have not been studied in detail. We demonstrate here that FFAR1 and FFAR4 mediate migration induced by OA in MDA-MB-231 and MCF-7 breast cancer cells. Moreover, OA induces migration, invasion, AKT1 and AKT2 activation, 12-LOX secretion and an increase of NFκB-DNA binding activity in breast cancer cells. Cell migration requires FFAR1, FFAR4, EGFR, AKT and PI3K activity, whereas invasion is mediated though a PI3K/Akt-dependent pathway. Furthermore, OA promotes relocalization of paxillin to focal contacts and it requires PI3K and EGFR activity, whereas NFκB-DNA binding activity requires PI3K and AKT activity.

Contributions of 12/15-Lipoxygenase to Bleeding in the Brain Following Ischemic Stroke

Ischemic strokes are caused by one or more blood clots that typically obstruct one of the major arteries in the brain, but frequently also result in leakage of the blood-brain barrier and subsequent hemorrhage. While it has long been known that the enzyme 12/15-lipoxygenase (12/15-LOX) is up-regulated following ischemic strokes and contributes to neuronal cell death, recent research has shown an additional major role for 12/15-LOX in causing this hemorrhagic transformation. These findings have important implications for the use of 12/15-LOX inhibitors in the treatment of stroke.

Overexpression of G protein-coupled receptor 31 as a poor prognosticator in human colorectal cancer

AIM

To investigate the expression of G protein-coupled receptor 31 (GPR31) and its clinical significance in human colorectal cancer (CRC).

METHODS

To determine the association between the GPR31 expression and the prognosis of patients, we obtained paraffin-embedded pathological specimens from 466 CRC patients who underwent initial resection. A total of 321 patients from the First Affiliated Hospital of Sun Yat-sen University from January 1996 to December 2008 were included as a training cohort, whereas 145 patients from the Sixth Affiliated Hospital of Sun Yat-sen University from January 2007 to November 2008 were included as a validation cohort. We examined GPR31 expression levels in CRC tissues from two independent cohorts via immunohistochemical staining. All patients were categorized into either a GPR31 low expression group or a GPR31 high expression group. The clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group were compared.

RESULTS

We compared the clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group. Significant differences were observed in the number of patients in pM classification between patients in the GPR31 low expression group and GPR31 high expression group (P = 0.007). The five-year survival and tumor-free survival rates of patients were 84.3% and 82.2% in the GPR31 low expression group, respectively, and both rates were 59.7% in the GPR31 high expression group (P < 0.05). Results of the Cox proportional hazard regression model revealed that GPR31 upregulation was associated with shorter overall survival and tumor-free survival of patients with CRC (P < 0.05). Multivariate analysis identified GPR31 expression in colorectal cancer as an independent predictive factor of CRC patient survival (P < 0.05).

CONCLUSION

High GPR31 expression levels were found to be correlated with pM classification of CRC and to serve as an independent predictive factor of poor survival of CRC patients.

LncRNA NKILA suppresses TGF-β-induced epithelial-mesenchymal transition by blocking NF-κB signaling in breast cancer

TGF-β plays a central role in mediating epithelial-mesenchymal transition (EMT) by activating the Smad pathway. In addition, accumulating evidence suggests that TGF-β-induced EMT is NF-κB-dependent in various cancer types. However, it is largely unclear if NF-κB mediates TGF-β-induced EMT in breast cancer, and if this mediation occurs, the regulatory mechanisms are unknown. In our study, we found that TGF-β activates the NF-κB pathway. Inhibition of NF-κB signaling markedly abrogates TGF-β-induced EMT. By studying the regulatory mechanism of TGF-β-induced NF-κB signaling, we found that lncRNA NKILA was upregulated by TGF-β and was essential for the negative feedback regulation of the NF-κB pathway. Accordingly, overexpression of NKILA significantly reduced TGF-β-induced tumor metastasis in vivo. Consistent with the results from mice, the expression of NKILA was negatively correlated with EMT phenotypes in clinical breast cancer samples. Collectively, our study indicated that the NKILA-mediated negative feedback affects TGF-β-induced NF-κB activation and that NKILA may be a therapeutic molecule in breast cancer metastasis via inhibition of EMT.

Fatty Acids and Calcium Regulation in Prostate Cancer

Prostate cancer is a widespread malignancy characterized by a comparative ease of primary diagnosis and difficulty in choosing the individualized course of treatment. Management of prostate cancer would benefit from a clearer understanding of the molecular mechanisms behind the transition to the lethal, late-stage forms of the disease, which could potentially yield new biomarkers for differential prognosis and treatment prioritization in addition to possible new therapeutic targets. Epidemiological research has uncovered a significant correlation of prostate cancer incidence and progression with the intake (and often co-intake) of fatty acids and calcium. Additionally, there is evidence of the impact of these nutrients on intracellular signaling, including the mechanisms mediated by the calcium ion as a second messenger. The present review surveys the recent literature on the molecular mechanisms associated with the critical steps in the prostate cancer progression, with special attention paid to the regulation of these processes by fatty acids and calcium homeostasis. Testable hypotheses are put forward that integrate some of the recent results in a more unified picture of these phenomena at the interface of cell signaling and metabolism.

The Platelet Lifeline to Cancer: Challenges and Opportunities

Besides their function in limiting blood loss and promoting wound healing, experimental evidence has highlighted platelets as active players in all steps of tumorigenesis including tumor growth, tumor cell extravasation, and metastasis. Additionally, thrombocytosis in cancer patients is associated with adverse patient survival. Due to the secretion of large amounts of microparticles and exosomes, platelets are well positioned to coordinate both local and distant tumor-host crosstalk. Here, we present a review of recent discoveries in the field of platelet biology and the role of platelets in cancer progression as well as challenges in targeting platelets for cancer treatment.

Candidate Biomarkers for Oral Squamous Cell Carcinoma: Differential Expression of Oxidative Stress-Related Genes

Background:

Alteration in the biotransformation of exogenous compounds can result in production of reactive oxygen species (ROS), which can predispose cells to malignant transformation in the head and neck. This study aimed to evaluate the expression of genes involved in antioxidant metabolism in the oral squamous cell carcinoma (OSCC).

Methods:

The expression of eighty-four genes was evaluated in OSCC and non-tumor tissues by quantitative real-time polymerase chain reaction using the TaqMan Gene Expression Array. The biological mechanisms related to the differentially expressed genes were investigated using Gene – NCBI, KEGG, UNIPROT and REACTOME databases.

Results:

Twenty-one genes encoding enzymes involved in antioxidant metabolism were differentially expressed in the OSCC case. Four genes (ATOX1, PRDX4, PRNP, and SOD2) were up-regulated, and seventeen (ALOX12, CAT, CSDE1, DHCR24, DUOX1, DUOX2, EPHX2, GLRX2, GPX3, GSR, GSTZ1, MGST3, PRDX1, OXR1, OXSR1, SOD1, and SOD3) were down-regulated. We identified 14 possible novel biomarkers for OSCC. The differentially expressed genes appeared related to important biological processes involved in carcinogenesis, such as inflammation, angiogenesis, apoptosis, genomic instability, invasion, survival, and cell proliferation.

Conclusions:

Our study identified novel biomarkers which might warrant further investigation regarding OSCC pathogenesis since the altered expression in the genes can modulate biological processes related to oxidative stress and predispose cells to malignant transformation in the oral cavity.

12-Lipoxygenase promotes invasion and metastasis of human gastric cancer cells via epithelial-mesenchymal transition

The role of 12-lipoxygenase (12-LOX) in tumorigenesis has been well established in several types of human cancer, including gastric cancer. It was reported that epithelial-mesenchymal transition (EMT) contributes to tumor invasion and metastasis. However, whether 12-LOX promotes the invasion and metastasis of human gastric cancer cells via EMT remains to be elucidated. In the present study, the expression of 12-LOX and EMT markers, N-cadherin and E-cadherin, was evaluated in gastric cancer and adjacent normal mucosa samples by immunohistochemical analysis. 12-LOX-overexpressing gastric cancer cells were established via lentiviral transfection of SCG-7901 cells. Wound-healing and Transwell assays were performed to examine the regulation of cell metastasis and invasion by 12-LOX. Furthermore, the regulation of N-cadherin expression by 12-LOX was evaluated using reverse transcription-quantitative polymerase chain reaction and western blotting. The results revealed that the expression of 12-LOX and N-cadherin was significantly higher in gastric cancer compared with that in adjacent normal mucosa tissues (P<0.05). By contrast, the expression of E-cadherin was significantly decreased in gastric cancer compared with that in adjacent normal mucosa tissues (P<0.05). Furthermore, the expression of 12-LOX was positively associated with N-cadherin expression in gastric cancer tissues. 12-LOX-overexpressing gastric cancer cells exhibited significantly increased invasion and migration abilities compared with the empty vector and control groups. The expression of N-cadherin in 12-LOX-overexpressing gastric cancer cells was increased compared with that in the empty vector and control groups. The present study suggests that EMT may be involved in the promotion of the invasion and metastasis of human gastric cancer cells by 12-LOX.

BCL6B suppresses proliferation and migration of colorectal carcinoma cells through inhibition of the PI3K/AKT signaling pathway

B‑cell CLL/lymphoma 6 member B (BCL6B), a BCL6‑homologous gene, has been reported to be a tumor suppressor that is silenced in a variety of human cancers, including colorectal cancer (CRC). Although it was recently demonstrated that reduced expression of BCL6B is associated with tumor stage and lymph node metastasis in CRC, little is known on whether BCL6B contributes to CRC development, or the related underlying mechanism. The aim of the present study was to detect BCL6B expression in CRC cells, and determine the molecular mechanisms underlying the role of BCL6B in CRC development by investigating cell proliferation and migration in vitro. As a result, BCL6B expression was found to be notably repressed in CRC cells compared with normal intestinal epithelial cells by reverse transcription‑polymerase chain reaction and western blot analysis. CRC cell proliferation was significantly inhibited by BCL6B upregulation, as indicated by MTT and colony‑forming assays. Cell apoptosis was markedly induced, as indicated by flow cytometry, and BCL6B‑transfected CRC cells exhibited decreased migration ability. Additionally, BCL6B overexpression diminished the phosphorylation level of AKT in CRC cells. These effects of BCL6B were empowered by treatment with the specific phosphoinositide 3 kinase (PI3K)/AKT inhibitor LY294002. Furthermore, overexpression of BCL6B resulted in upregulation of E‑cadherin and downregulation of cyclin D1 and matrix metalloproteinase‑9, which were strongly enhanced by LY294002. In conclusion, the findings of the present study demonstrated that BCL6B suppressed the proliferation and migration of CRC cells indirectly, via inhibition of PI3K.

Antiplatelet agents for cancer treatment: a real perspective or just an echo from the past?

The association between coagulation and cancer development has been observed for centuries. However, the connection between inflammation and malignancy is also well-recognized. The plethora of evidence indicates that among multiple hemostasis components, platelets play major roles in cancer progression by providing surface and granular contents for several interactions as well as behaving like immune cells. Therefore, the anticancer potential of anti-platelet therapy has been intensively investigated for many years. Anti-platelet agents may prevent cancer, decrease tumor growth, and metastatic potential, as well as improve survival of cancer patients. On the other hand, there are suggestions that antiplatelet treatment may promote solid tumor development in a phenomenon described as "cancers follow bleeding." The controversies around antiplatelet agents justify insight into the subject to establish what, if any, role platelet-directed therapy has in the continuum of anticancer management.

Is heterotopic ossification getting nervous?: The role of the peripheral nervous system in heterotopic ossification

Heterotopic ossification (HO), or de novo bone formation in soft tissue, is often observed following traumatic injury. Recent studies suggest that peripheral nerves may play a key functional role in this process. The results supporting a neurological basis for HO are examined in this article. Evidence supports the fact that BMPs released from bone matrix possess the capacity to induce HO. However, the process cannot be recapitulated using recombinant proteins without extremely high doses suggesting other components are required for this process. Study of injuries that increase risk for HO, i.e. amputation, hip replacement, elbow fracture, burn, and CNS injury suggests that a likely candidate is traumatic injury of adjacent peripheral nerves. Recent studies suggest neuroinflammation may play a key functional role, by its ability to open the blood-nerve barrier (BNB). Barrier opening is characterized by a change in permeability and is experimentally assessed by the ability of Evans blue dye to enter the endoneurium of peripheral nerves. A combination of BMP and barrier opening is required to activate bone progenitors in the endoneurial compartment. This process is referred to as "neurogenic HO".

NCOA5 promotes proliferation, migration and invasion of colorectal cancer cells via activation of PI3K/AKT pathway

The nuclear receptor coactivator 5 (NCOA5) displays both coactivator and corepressor functions. Previous studies showed that alteration of NCOA5 participates in carcinogenesis and progression. However, its roles in colorectal cancer (CRC) remain unknown. Herein, we demonstrated that expression of NCOA5 in human CRC tissues was notably higher than that in adjacent tissues, which significantly correlated with clinicopathological features such as length of tumor, regional lymph node staging and cancer staging. Knockdown of NCOA5 markedly suppressed proliferation, migration and invasion of SW620 high malignant CRC cells. Silencing of NCOA5 also inhibited in vivo growth of SW620 CRC subcutaneously xenografted tumors in athymic BALB/c nude mice. Meanwhile, Overexpression of NCOA5 facilitated these processes in SW480 low malignant CRC cells. Furthermore, knockdown of NCOA5 induced cell cycle G1 phase arrest in SW620 cells, whereas overexpression of NCOA5 promoted G1 to S phase transition in SW480 cells. Mechanistic studies revealed that NCOA5 upregulated phospho-protein kinase B (p-PKB/AKT), Cyclin D1 and matrix metalloproteinase 9 (MMP9) as well as downregulated P27 in CRC cells. Notably, PI3K inhibitor LY294002 obviously attenuated the effects of NCOA5 on p-AKT, Cyclin D1, P27 and MMP9. Moreover, LY294002 and knockdown of Cyclin D1 or MMP9 remarkably blocked the tumor-promoting activity of NCOA5. Collectively, NCOA5 promoted CRC cell proliferation, migration and invasion by upregulating Cyclin D1 and MMP9 while downregulating P27 to a great extent via activating PI3K/AKT signaling pathway. These findings suggested that NCOA5 exhibits an oncogenic effect in human CRC and represents a novel therapeutic target for CRC.

12-Lipoxygenase and 12-hydroxyeicosatetraenoic acid regulate hypoxic angiogenesis and survival of pulmonary artery endothelial cells via PI3K/Akt pathway

Dysfunction and injury of endothelial cells play critical roles in pulmonary arterial hypertension, including aberrant proliferation, suppressed apoptosis, and excessive angiogenesis. The 12-lipoxygenase and 12-hydroxyeicosatetraenoic acid pathway, which has been considered as a crucial mediator, elevates pulmonary vascular resistance and pulmonary arterial pressure. However, the mechanisms underlying the bioactivity of 12-hydroxyeicosatetraenoic acid in pulmonary vasculature, especially in endothelial cells, are still elusive. Thus we aim to determine the key role of 12-lipoxygenase/12-hydroxyeicosatetraenoic acid in angiogenesis and survival of pulmonary artery endothelial cells and ascertain the signaling pathways participating in the pathological process. Here we establish that hypoxia increases the formation of endogenous 12-hydroxyeicosatetraenoic acid through stimulation of 12-lipoxygenase. Furthermore, we put forward new information that 12-hydroxyeicosatetraenoic acid promotes endothelial cell migration and tube formation, whereas it inhibits the serum deprivation-induced apoptotic responses under hypoxia. Particularly, the regulatory effects of 12-lipoxygenase/12-hydroxyeicosatetraenoic acid on pulmonary artery endothelial cells, at least in part, depend on phosphatidylinositol 3-kinase (PI3K)/Akt signaling activation. Taken together, these results may have significant implications for understanding of pulmonary hypertension and offer a potential therapeutic concept focusing on the 12-lipoxygenase/12-hydroxyeicosatetraenoic acid signaling system.

Lysophosphatidic Acid Is Associated with Atherosclerotic Plaque Instability by Regulating NF-κB Dependent Matrix Metalloproteinase-9 Expression via LPA2 in Macrophages

Lysophosphatidic acid (LPA), one of the simplest phospholipid signaling molecules, participates in formation and disruption of atherosclerotic plaque. Matrix metalloproteinases (MMPs) contribute to atherosclerotic plaque rupture by involving in extracellular matrix (ECM) degradation and then thinning fibrous cap. Our previous study demonstrated that macrophage-derived MMP-9 was associated with coronary plaque instability, but the relationship between LPA and MMP-9 remains unclear. The present work therefore aimed at elucidating association between LPA and MMP-9 and the regulation mechanism of LPA on MMP-9 in macrophages. We found that plasma LPA and MMP-9 levels were correlated positively (r = 0.31, P < 0.05) and both elevated significantly in patients with acute myocardial infarct (AMI). Consistent with peripheral blood levels, histochemical staining indicated that autotaxin (ATX), LPA-producing ectoenzyme, and MMP-9 were expressed frequently in the necrotic core and fibrous cap of human unstable plaques, which might increase the instability of plaque. Experiments in vitro were done with THP-1-derived macrophages and showed that LPA enhanced the expression, secretion and activity of MMP-9 in a time- and dose-dependent manner. Induction of LPA on pro-MMP-9 and active-MMP-9 was confirmed in human peripheral blood monocyte-derived macrophages. PDTC, NF-κB inhibitor, but not inhibitor of AP-1 and PPARγ, effectively prevented LPA-induced MMP-9 expression and NF-κB p65 siRNA decreased MMP-9 transcription, confirming that LPA might induce MMP-9 elevation by activating NF-κB pathway. In addition, knockdown of LPA₂ attenuated LPA-induced MMP-9 expression and nucleus p65 levels. These findings revealed that LPA upregulated the expression of MMP-9 through activating NF-κB pathway in the LPA₂ dependent manner, hence blocking LPA receptors signaling may provide therapeutic strategy to target plaque destabilization.

Baicalein Inhibits the Migration and Invasion of B16F10 Mouse Melanoma Cells through Inactivation of the PI3K/Akt Signaling Pathway

Baicalein, a natural flavonoid obtained from the rhizome of Scutellaria baicalensis Georgi, has been reported to have anticancer activities in several human cancer cell lines. However, its antimetastatic effects and associated mechanisms in melanoma cells have not been extensively studied. The current study examined the effects of baicalein on cell motility and anti-invasive activity using mouse melanoma B16F10 cells. Within the noncytotoxic concentration range, baicalein significantly inhibited the cell motility and invasiveness of B16F10 cells in a concentration-dependent manner. Baicalein also reduced the activity and expression of matrix metalloproteinase (MMP)-2 and -9; however, the levels of tissue inhibitor of metalloproteinase-1 and -2 were concomitantly increased. The inhibitory effects of baicalein on cell motility and invasiveness were found to be associated with its tightening of tight junction (TJ), which was demonstrated by an increase in transepithelial electrical resistance and downregulation of the claudin family of proteins. Additionally, treatment with baicalein markedly reduced the expression levels of lipopolysaccharide-induced phosphorylated Akt and the invasive activity in B16F10 cells. Taken together, these results suggest that baicalein inhibits B16F10 melanoma cell migration and invasion by reducing the expression of MMPs and tightening TJ through the suppression of claudin expression, possibly in association with a suppression of the phosphoinositide 3-kinase/Akt signaling pathway.

Convergence of eicosanoid and integrin biology: Role of Src in 12-LOX activation

12-Lipoxygenase (12-LOX) metabolizes arachidonic acid to 12(S)-hydroxyeicosatetraenoic acid, or 12(S)-HETE, a proinflammatory bioactive lipid implicated in tumor angiogenesis, growth, and metastasis. The mechanisms underlying 12-LOX-mediated signaling in cancer progression are still ill-defined. In the present study we demonstrate that 12-LOX phosphorylation and subsequent enzymatic activity occurs after integrin β4 stimulation and Src kinase recruitment to the integrin subunit. Inhibition of Src activity by PP2 or Src dominant-negative mutants reduced 12-LOX tyrosine phosphorylation and 12(S)-HETE production in response to integrin β4 stimulation in A431 cells. The pertinent Src-targeted residues for 12-LOX activity were mapped to Y19 and Y614, where 12-LOX mutants Y19F and Y614F showed 70% less enzymatic activity. Furthermore, we have shown that the 12-LOX activity modulated by these residues impacts migration. To our knowledge, this is the first report that c-Src kinase activity is required for β4-integrin-mediated phosphorylation of 12-LOX.

Thrombin-unique coagulation system protein with multifaceted impacts on cancer and metastasis

The association between blood coagulation and cancer development is well recognized. Thrombin, the pleiotropic enzyme best known for its contribution to fibrin formation and platelet aggregation during vascular hemostasis, may also trigger cellular events through protease-activated receptors, PAR-1 and PAR-4, leading to cancer progression. Our pioneering findings provided evidence that thrombin contributes to cancer metastasis by increasing adhesive potential of malignant cells. However, there is evidence that thrombin regulates every step of cancer dissemination: (1) cancer cell invasion, detachment from primary tumor, migration; (2) entering the blood vessel; (3) surviving in vasculature; (4) extravasation; (5) implantation in host organs. Recent studies have provided new molecular data about thrombin generation in cancer patients and the mechanisms by which thrombin contributes to transendothelial migration, platelet/tumor cell interactions, angiogenesis, and other processes. Though a great deal is known regarding the role of thrombin in cancer dissemination, there are new data for multiple thrombin-mediated events that justify devoting focus to this topic with a comprehensive approach.

Protease-activated receptors (PARs)--biology and role in cancer invasion and metastasis

Although many studies have demonstrated that components of the hemostatic system may be involved in signaling leading to cancer progression, the potential mechanisms by which they contribute to cancer dissemination are not yet precisely understood. Among known coagulant factors, tissue factor (TF) and thrombin play a pivotal role in cancer invasion. They may be generated in the tumor microenvironment independently of blood coagulation and can induce cell signaling through activation of protease-activated receptors (PARs). PARs are transmembrane G-protein-coupled receptors (GPCRs) that are activated by a unique proteolytic mechanism. They play important roles in vascular physiology, neural tube closure, hemostasis, and inflammation. All of these agents (TF, thrombin, PARs—mainly PAR-1 and PAR-2) are thought to promote cancer invasion and metastasis at least in part by facilitating tumor cell migration, angiogenesis, and interactions with host vascular cells, including platelets, fibroblasts, and endothelial cells lining blood vessels. Here, we discuss the role of PARs and their activators in cancer progression, focusing on TF- and thrombin-mediated actions. Therapeutic options tailored specifically to inhibit PAR-induced signaling in cancer patients are presented as well.

Anti-cancer effects of baicalein in non-small cell lung cancer in-vitro and in-vivo

Background

Baicalein is a widely used Chinese herbal medicine derived from Scutellaria baicalenesis, which has been traditionally used as anti-inflammatory and anti-cancer therapy. In this study we examined the anti-tumour pathways activated following baicalein treatment in non-small cell lung cancer (NSCLC), both in-vitro and in-vivo.

Methods

The effect of baicalein treatment on H-460 cells in-vitro was assessed using both BrdU assay (cell proliferation) and High Content Screening (multi-parameter apoptosis assay). A xenograft nude mouse model was subsequently established using these cells and the effect of baicalein on tumour growth and survival assessed in-vivo. Tumours were harvested from these mice and histological tissue analysis carried out. VEGF, 12-lipoxygenase and microvessel density (CD-31) were assessed by immunohistochemistry (IHC), while H and E staining was carried out to assess mitotic index. Gene expression profiling was carried out on corresponding RNA samples using Human Cancer Pathway Finder Arrays and qRT-PCR, with further gene expression analysis carried out using qRT-PCR.

Results

Baicalein significantly decreased lung cancer proliferation in H-460 cells in a dose dependent manner. At the functional level, a dose-dependent induction in apoptosis associated with decreased cellular f-actin content, an increase in nuclear condensation and an increase in mitochondrial mass potential was observed. Orthotopic treatment of experimental H-460 tumours in athymic nude mice with baicalein significantly (p < 0.05) reduced tumour growth and prolonged survival. Histological analysis of resulting tumour xenografts demonstrated reduced expression of both 12-lipoxygenase and VEGF proteins in baicalein-treated tumours, relative to untreated. A significant (p < 0.01) reduction in both mitotic index and micro-vessel density was observed following baicalein treatment. Gene expression profiling revealed a reduction (p < 0.01) in both VEGF and FGFR-2 following baicalein treatment, with a corresponding increase (p < 0.001) in RB-1.

Conclusion

This study is the first to demonstrate efficacy of baicalein both in-vitro and in-vivo in NSCLC. These effects may be mediated in part through a reduction in both cell cycle progression and angiogenesis. At the molecular level, alterations in expression of VEGF, FGFR-2, and RB-1 have been implicated, suggesting a molecular mechanism underlying this in-vivo effect.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2740-0) contains supplementary material, which is available to authorized users.

Regulation of Dipeptidyl Peptidase IV in the Post-stroke Rat Brain and In Vitro Ischemia: Implications for Chemokine-Mediated Neural Progenitor Cell Migration and Angiogenesis

Cerebral ischemia evokes abnormal release of proteases in the brain microenvironment that spatiotemporally impact angio-neurogenesis. Dipeptidyl peptidase IV (DPPIV), a cell surface and secreted protease, has been implicated in extracellular matrix remodeling by regulating cell adhesion, migration, and angiogenesis through modifying the functions of the major chemokine stromal-derived factor, SDF1. To elucidate the possible association of DPPIV in ischemic brain, we examined the expression of DPPIV in the post-stroke rat brain and under in vitro ischemia by oxygen glucose deprivation (OGD). We further investigated the effects of DPPIV on SDF1 mediated in vitro chemotactic and angiogenic functions. DPPIV protein and mRNA levels were significantly upregulated during repair phase in the ischemic cortex of the rat brain, specifically in neurons, astrocytes, and endothelial cells. In vitro exposure of Neuro-2a neuronal cells and rat brain endothelial cells to OGD resulted in upregulation of DPPIV. In vitro functional analysis showed that DPPIV decreases the SDF1-mediated angiogenic potential of rat brain endothelial cells and inhibits the migration of Neuro-2a and neural progenitor cells. Western blot analyses revealed decreased levels of phosphorylated ERK1/2 and AKT in the presence of DPPIV. DPPIV inhibitor restored the effects of SDF1. Proteome profile array screening further revealed that DPPIV decreases matrix metalloproteinase-9, a key downstream effector of ERK-AKT signaling pathways. Overall, delayed induction of DPPIV in response to ischemia/reperfusion suggests that DPPIV may play an important role in endogenous brain tissue remodeling and repair processes. This may be mediated through modulation of SDF1-mediated cell migration and angiogenesis.

Causes and consequences of nuclear envelope alterations in tumour progression

Morphological changes in the size and shape of the nucleus are highly prevalent in cancer, but the underlying molecular mechanisms and the functional relevance remain poorly understood. Nuclear envelope proteins, which can modulate nuclear shape and organization, have emerged as key components in a variety of signalling pathways long implicated in tumourigenesis and metastasis. The expression of nuclear envelope proteins is altered in many cancers, and changes in levels of nuclear envelope proteins lamins A and C are associated with poor prognosis in multiple human cancers. In this review we highlight the role of the nuclear envelope in different processes important for tumour initiation and cancer progression, with a focus on lamins A and C. Lamin A/C controls many cellular processes with key roles in cancer, including cell invasion, stemness, genomic stability, signal transduction, transcriptional regulation, and resistance to mechanical stress. In addition, we discuss potential mechanisms mediating the changes in lamin levels observed in many cancers. A better understanding of cause-and-effect relationships between lamin expression and tumour progression could reveal important mechanisms for coordinated regulation of oncogenic processes, and indicate therapeutic vulnerabilities that could be exploited for improved patient outcome.