Leucine rich α2 glycoprotein 1 derived from malignant pleural mesothelioma cells facilitates macrophage M2 phenotypes.

Background: Macrophages constitute the main part of infiltrating immune cells in Malignant pleural mesothelioma (MPM) and abnormally high ratios of M2 macrophages are present in both pleural effusion and tissue samples of MPM patients. Whether MPM cells affect formation of M2 macrophages is poorly understood. In this study, we focused on identification of MPM-cells-derived soluble factors with M2-promoting effects. Methods: Media of malignant pleural mesothelioma cells were collected and soluble factors affecting macrophages were analyzed by mass spectrometry. TGF-ß receptor inhibitor SB431542 was used as the entry point to explore the downstream mechanism of action by qRT-PCR, WB and immunofluorescence. Results: The serum-free culture media collected from the human MPM cells Meso1 and Meso2 significantly enhanced expression of the M2 signature molecules including IL-10, TGF-ß and CD206 in the human macrophages THP-1, while the culture medium of the human MPM cells H2452 did not show such M2-promoting effects. Analysis of proteins by mass spectrometry and ELISA suggested that Leucine rich α2 glycoprotein 1(LRG1) was a potential candidate. LRG1 time- and dose-dependently increased expression of the M2 signature molecules, confirming its M2-promoting effects. Furthermore, LRG1's M2-promoting effects were reduced by the TGF-ß receptor inhibitor SB431542, and LRG1 increased phosphorylation of Smad2, indicating that M2-promoting effects of LRG1 were via the TGF-ß receptor/Smad2 signaling pathway. Conclusions: Our results provide a potential M2-promoting new member, LRG1, which contributes to the immune escape of MPM via the TGF-ß receptor/Smad2 signaling pathway.

Dihydrotanshinone I inhibits gallbladder cancer growth by targeting the Keap1-Nrf2 signaling pathway and Nrf2 phosphorylation.

BACKGROUND: Gallbladder cancer (GBC) poses a significant risk to human health. Its development is influenced by numerous factors, particularly the homeostasis of reactive oxygen species (ROS) within cells. This homeostasis is crucial for tumor cell survival, and abnormal regulation of ROS is associated with the occurrence and progression of many cancers. Dihydrotanshinone I (DHT I), a biologically effective ingredient isolated from Salvia miltiorrhiza, has exhibited cytotoxic properties against various tumor cells by inducing apoptosis. However, the precise molecular mechanisms by which dht I exerts its cytotoxic effects remain unclear. PURPOSE: To explore the anti-tumor impact of dht I on GBC and elucidate the potential molecular mechanisms. METHODS: The proliferation of GBC cells, NOZ and SGC-996, was assessed using various assays, including CCK-8 assay, colony formation assay and EdU staining. We also examined cell apoptosis, cell cycle progression, ROS levels, and alterations in mitochondrial membrane potential to delve into the intricate molecular mechanism. Quantitative PCR (qPCR), immunofluorescence staining, and Western blotting were performed to evaluate target gene expression at both the mRNA and protein levels. The correlation between nuclear factor erythroid 2-related factor 2 (Nrf2) and kelch-like ECH-associated protein 1 (Keap1) were examined using co-immunoprecipitation. Finally, the in vivo effect of dht I was investigated using a xenograft model of gallbladder cancer in mice. RESULTS: Our research findings indicated that dht I exerted cytotoxic effects on GBC cells, including inhibiting proliferation, disrupting mitochondrial membrane potential, inducing oxidative stress and apoptosis. Our in vivo studies substantiated the inhibition of dht I on tumor growth in xenograft nude mice. Mechanistically, dht I primarily targeted Nrf2 by promoting Keap1 mediated Nrf2 degradation and inhibiting protein kinase C (PKC) induced Nrf2 phosphorylation. This leads to the suppression of Nrf2 nuclear translocation and reduction of its target gene expression. Moreover, Nrf2 overexpression effectively counteracted the anti-tumor effects of dht I, while Nrf2 knockdown significantly enhanced the inhibitory effect of dht I on GBC. Meanwhile, PKC inhibitors and nuclear import inhibitors increased the sensitivity of GBC cells to dht I treatment. Conversely, Nrf2 activators, proteasome inhibitors, antioxidants and PKC activators all antagonized dht I induced apoptosis and ROS generation in NOZ and SGC-996 cells. CONCLUSION: Our findings indicated that dht I inhibited the growth of GBC cells by regulating the Keap1-Nrf2 signaling pathway and Nrf2 phosphorylation. These insights provide a strong rationale for further investigation of dht I as a potential therapeutic agent for GBC treatment.

Demethylase FTO enhances the PI3K/Akt signaling to promote gastric cancer malignancy.

Enhanced expression of fat mass and obesity-associated protein (FTO) has been reported in gastric cancer (GC). Bioinformatical studies indicate that FTO expression is correlated with the patients' overall survival (OS). How FTO exerts its promotion effects on GC development and affects OS remains largely unknown. In this study, the prognostic relevance of FTO expression in human GC tissues and the molecular mechanisms underlying FTO's promotion roles were investigated. Kaplan-Meier survival curve analysis revealed that the patients with high FTO levels had shorter OS compared to those with low FTO expression (p < 0.0001). Univariate and multivariate COX regression analyses showed that the patients' OS was affected by FTO status (p < 0.0001, p = 0.001, respectively). FTO knockdown in HGC27 cells by shRNAs reduced cell proliferation, colony formation, migration and invasion, while FTO overexpression in AGS cells had reverse effects. FTO knockdown in HGC27 cells also suppressed the tumor growth in a mouse xenograft model. High-throughput transcriptome sequencing indicated that FTO enhanced the PI3K/Akt signaling, which was confirmed in vitro. In summary, our research revealed that FTO is a potent prognostic biomarker of GC. FTO enhances the PI3K/Akt signaling and thus, promotes GC development.

Tumor-activated neutrophils promote metastasis in breast cancer via the G-CSF-RLN2-MMP-9 axis.

The immune component of the tumor microenvironment is essential for the regulation of cancer progression. In breast cancer (BC), a patient's tumor mass is frequently infiltrated by neutrophils (tumor-associated neutrophils, TANs). Our study addressed the role of TANs and their mechanism of action in BC. Using quantitative IHC, ROC, and Cox analysis, we demonstrated that a high density of TANs infiltrating the tumor parenchyma was predictive of poor prognosis and of decreased progression-free survival of patients with BC, who underwent surgical tumor removal without previous neoadjuvant chemotherapy, in 3 different cohorts: training, validation, and independent cohorts. Conditioned medium from human BC cell lines prolonged the lifespan of healthy donor neutrophils ex vivo. Neutrophils activated by the supernatants of BC lines demonstrated an increased ability to stimulate proliferation, migration, and invasive activity of BC cells. Cytokines involved in this process were identified using antibody arrays. The relationship between these cytokines and the density of TANs was validated by ELISA and IHC in fresh BC surgical samples. It was determined that tumor-derived G-CSF significantly extended the lifespan and increased the metastasis-promoting activities of neutrophils via the PI3K-AKT and NF-κB pathways. Simultaneously, TAN-derived RLN2 promoted the migratory abilities of MCF7 cells via PI3K-AKT-MMP-9. Analysis of tumor tissues from 20 patients with BC identified a positive correlation between the density of TANs and the activation of the G-CSF-RLN2-MMP-9 axis. Finally, our data demonstrated that TANs in human BC have detrimental effects, supporting malignant cell invasion and migration.

Agonists Specific for κ-Opioid Receptor Induces Apoptosis of HCC Cells Through Enhanced Endoplasmic Reticulum Stress.

Cancer pain is an important factor affecting life quality of patients especially in the advanced stage and relieving pain is one of fundamental strategies for cancer treatment. Opioids such as morphine are the most widely used in clinics. However, they have been reported to be associated with the occurrence and development of several types of cancer. Thus, search for an opioid that has analgesic effect and can retard cancer progress simultaneously is critical for cancer management. In this study, we first examined the expression of µ and κ (MOR and KOR) in cell lines and tumor tissues of hepatocellular carcinoma (HCC), a malignant tumor with high mortality, and then compared the effects of opioid receptors-specific agonists on malignant phenotypes of HCC cells in vitro and tumor growth in an HCC xenograft mouse model. KOR and MOR were found to be highly expressed in HCC cell lines and HCC tissues. The KOR-specific agonist U50488h, oxycodone (agonist for both KOR and MOR) and the MOR-specific agonist morphine inhibited HCC cell proliferation, while only U50488h and oxycodone suppressed colony formation and migration of HCC cells. U50488h and oxycodone, but not morphine, induced HCC apoptosis. Further detection of PERK, GRP78 and CHOP revealed that PERK signaling was upregulated by treatment with U50488h, while treatment with the PERK inhibitor GSK2656157 partially reversed the promotion of apoptosis and inhibition of cell proliferation by U50488h, indicating that endoplasmic reticulum stress is associated with its suppressing effect on HCC malignant phenotypes. Similar to the in vitro results, HCC growth was significantly reduced by administration of U50488h and oxycodone, but not by morphine, in the HCC xenograft mouse model. PERK and caspase-3 in the HCC tissues were up-regulated by U50488h treatment as detected by immunohistochemistry and western blotting. Taken together, our results revealed that activation of KOR by U50488h inhibited malignant phenotypes of HCC both in vitro and in vivo, while activation of MOR by morphine did not have such effect. Because of their dual roles in the relief of pain and in the suppression of malignant phenotypes, opioids such as U50488h that act on KOR should be considered as the first choice for HCC management.

Assessment of the toxicity and carcinogenicity of double-walled carbon nanotubes in the rat lung after intratracheal instillation: a two-year study.

BACKGROUND: Considering the expanding industrial applications of carbon nanotubes (CNTs), safety assessment of these materials is far less than needed. Very few long-term in vivo studies have been carried out. This is the first 2-year in vivo study to assess the effects of double walled carbon nanotubes (DWCNTs) in the lung and pleura of rats after pulmonary exposure. METHODS: Rats were divided into six groups: untreated, Vehicle, 3 DWCNT groups (0.12 mg/rat, 0.25 mg/rat and 0.5 mg/rat), and MWCNT-7 (0.5 mg/rat). The test materials were administrated by intratracheal-intrapulmonary spraying (TIPS) every other day for 15 days. Rats were observed without further treatment until sacrifice. RESULTS: DWCNT were biopersistent in the rat lung and induced marked pulmonary inflammation with a significant increase in macrophage count and levels of the chemotactic cytokines CCL2 and CCL3. In addition, the 0.5 mg DWCNT treated rats had significantly higher pulmonary collagen deposition compared to the vehicle controls. The development of carcinomas in the lungs of rats treated with 0.5 mg DWCNT (4/24) was not quite statistically higher (p = 0.0502) than the vehicle control group (0/25), however, the overall incidence of lung tumor development, bronchiolo-alveolar adenoma and bronchiolo-alveolar carcinoma combined, in the lungs of rats treated with 0.5 mg DWCNT (7/24) was statistically higher (p < 0.05) than the vehicle control group (1/25). Notably, two of the rats treated with DWCNT, one in the 0.25 mg group and one in the 0.5 mg group, developed pleural mesotheliomas. However, both of these lesions developed in the visceral pleura, and unlike the rats administered MWCNT-7, rats administered DWCNT did not have elevated levels of HMGB1 in their pleural lavage fluids. This indicates that the mechanism by which the mesotheliomas that developed in the DWCNT treated rats is not relevant to humans. CONCLUSIONS: Our results demonstrate that the DWCNT fibers we tested are biopersistent in the rat lung and induce chronic inflammation. Rats treated with 0.5 mg DWCNT developed pleural fibrosis and lung tumors. These findings demonstrate that the possibility that at least some types of DWCNTs are fibrogenic and tumorigenic cannot be ignored.

Long Noncoding RNA Metastasis-Associated Lung Adenocarcinoma Transcript 1 in Extracellular Vesicles Promotes Hepatic Stellate Cell Activation, Liver Fibrosis and ß-Catenin Signaling Pathway.

Evidence shows that the long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (Lnc-MALAT1) is associated with activation of hepatic stellate cells (HSCs) and liver fibrosis in animal and in vitro studies. However, its roles in human liver fibrosis and the underlying mechanism in HSC activation are not yet defined. In our current study, the expression of Lnc-MALAT1 in the fibrotic liver tissues and in the plasma extracelllar vesicles (EVs) of liver fibrosis patients was detected by FISH and qRT-PCR. The results revealed that enhanced expression of Lnc-MALAT1 was co-localized with increased expression of the fibrotic markers (collagen I and α-SMA) and the Wnt/ß-catenin signaling proteins (ß-catenin, cyclinD1 and c-myc) in the fibrotic liver tissues. The level of Lnc-MALAT1 in the plasma EVs isolated from 60 liver fibrosis patients was significantly increased compared with that of the 46 control patients, and area under receiver operating curve (AUROC) analysis showed that plasma EVs-Lnc-MALAT1 was a potential diagnostic marker for liver fibrosis, especially for high liver fibrosis. Plasma EVs with highly expressed Lnc-MALAT1 derived from high liver fibrosis patients up-regulated the expression of the fibrotic markers and enhanced the Wnt/ß-catenin signaling in human hepatic stellate cells LX-2, and the fibrogenic effects in LX-2 were inhibited by Lnc-MALAT1 knock-down. Interestingly, TGF-ß1, a potent pro-fibrotic cytokine, promoted the expression of Lnc-MALAT1 in LX-2 and its pro-fibrotic effects were also abolished by siRNA for Lnc-MALAT1, suggesting that Lnc-MALAT1 probably functions as a common mediator in the activation and fibrogenesis of HSCs. Our results indicate that enhanced expression of Lnc-MALAT1 in the fibrotic liver stimulate the activation of HSCs and thus promote their fibrogenic activity. These results also provide evidences that Lnc-MALAT1 is a potential therapeutic target and plasma EVs-Lnc-MALAT1 is a potential diagnostic biomarker for liver fibrosis.

Posterior tibial nerve stimulation improves neurogenic bladder in rats with spinal cord injury through transient receptor potential/P2X signaling pathway.

BACKGROUND: To study the influences of posterior tibial nerve stimulation (PTNS) on neurogenic bladder and the expression of transient receptor potential (TRP) channels and P2X receptors in rats with spinal cord injury (SCI) and explore the possible mechanism. METHODS: SCI model was established by modified Allen's method and PTNS was performed. Urodynamic indexes and Haematoxylin and Eosine staining of bladder tissue were used to evaluate the therapeutic effect. The expression of TRP channels and P2X receptors in the bladder and dorsal root ganglia (DRG) was detected by real-time PCR and Western blot. RESULTS: The low compliance of bladder in treatment group was significantly improved compared with SCI group, and the infiltration of inflammatory cells in bladder tissue was significantly reduced. At the same time, the expression of TRP and P2X in bladder and DRG was partially restored after the treatment of PTNS. CONCLUSIONS: PTNS is an effective therapy for SCI-induced neurogenic bladder via the TRP/P2X signaling pathway.

Surfactant Proteins A/D-CD14 on Alveolar Macrophages Is a Common Pathway Associated With Phagocytosis of Nanomaterials and Cytokine Production.

Alveolar macrophages are responsible for clearance of airborne dust and pathogens. How they recognize and phagocytose a variety of engineered nanomaterials (ENMs) with different properties is an important issue for safety assessment of ENMs. Surfactant-associated proteins, specifically existing in the pulmonary surfactant, are important opsonins for phagocytosis of airborne microorganisms. The purposes of the current study are to understand whether opsonization of ENMs by surfactant-associated proteins promotes phagocytosis of ENMs and cytokine production, and to determine whether a common pathway for phagocytosis of ENMs with different properties exists. For these purposes, four ENMs, MWCNT-7, TiO2, SiO2, and fullerene C60, with different shapes, sizes, chemical compositions, and surface reactivities, were chosen for this study. Short-term pulmonary exposure to MWCNT-7, TiO2, SiO2, and C60 induced inflammation in the rat lung, and most of the administered ENMs were phagocytosed by alveolar macrophages. The ENMs were phagocytosed by isolated primary alveolar macrophages (PAMs) in vitro, and phagocytosis was enhanced by rat bronchioalveolar lavage fluid (BALF), suggesting that proteins in the BALF were associated with phagocytosis. Analysis of proteins bound to the 4 ENMs by LC/MS indicated that surfactant-associated proteins A and D (SP-A, SP-D) were common binding proteins for all the 4 ENMs. Both BALF and SP-A, but not SP-D, enhanced TNF-α production by MWCNT-7 treated PAMs; BALF, SP-A, and SP-D increased IL-1ß production in TiO2 and SiO2 treated PAMs; and BALF, SP-A, and SP-D enhanced IL-6 production in C60 treated PAMs. Knockdown of CD14, a receptor for SP-A/D, significantly reduced phagocytosis of ENMs and SP-A-enhanced cytokine production by PAMs. These results indicate that SP-A/D can opsonize all the test ENMs and enhance phagocytosis of the ENMs by alveolar macrophages through CD14, suggesting that SP-A/D-CD14 is a common pathway mediating phagocytosis of ENMs. Cytokine production induced by ENMs, however, is dependent on the type of ENM that is phagocytosed. Our results demonstrate a dual role for surfactant proteins as opsonins for both microbes and for inhaled dusts and fibers, including ENMs, allowing macrophages to recognize and remove the vast majority of these particles, thereby, greatly lessening their toxicity in the lung.

Exogenous L-carnitine ameliorates burn-induced cellular and mitochondrial injury of hepatocytes by restoring CPT1 activity.

BACKGROUND: Impaired hepatic fatty acid metabolism and persistent mitochondrial dysfunction are phenomena commonly associated with liver failure. Decreased serum levels of L-carnitine, a amino acid derivative involved in fatty-acid and energy metabolism, have been reported in severe burn patients. The current study aimed to evaluate the effects of L-carnitine supplementation on mitochondrial damage and other hepatocyte injuries following severe burns and the related mechanisms. METHODS: Serum carnitine and other indicators of hepatocytic injury, including AST, ALT, LDH, TG, and OCT, were analyzed in severe burn patients and healthy controls. A burn model was established on the back skin of rats; thereafter, carnitine was administered, and serum levels of the above indicators were evaluated along with Oil Red O and TUNEL staining, transmission electron microscopy, and assessment of mitochondrial membrane potential and carnitine palmitoyltransferase 1 (CPT1) activity and expression levels in the liver. HepG2 cells pretreated with the CPT1 inhibitor etomoxir were treated with or without carnitine for 24 h. Next, the above indicators were examined, and apoptotic cells were analyzed via flow cytometry. High-throughput sequencing of rat liver tissues identified several differentially expressed genes (Fabp4, Acacb, Acsm5, and Pnpla3) were confirmed using RT-qPCR. RESULTS: Substantially decreased serum levels of carnitine and increased levels of AST, ALT, LDH, and OCT were detected in severe burn patients and the burn model rats. Accumulation of TG, evident mitochondrial shrinkage, altered mitochondrial membrane potential, decreased ketogenesis, and reduced CPT1 activity were detected in the liver tissue of the burned rats. Carnitine administration recovered CPT1 activity and improved all indicators related to cellular and fatty acid metabolism and mitochondrial injury. Inhibition of CPT1 activity with etomoxir induced hepatocyte injuries similar to those in burn patients and burned rats; carnitine supplementation restored CPT1 activity and ameliorated these injuries. The expression levels of the differentially expressed genes Fabp4, Acacb, Acsm5, and Pnpla3 in the liver tissue from burned rats and etomoxir-treated hepatocytes were also restored by treatment with exogenous carnitine. CONCLUSION: Exogenous carnitine exerts protective effects against severe burn-induced cellular, fatty-acid metabolism, and mitochondrial dysfunction of hepatocytes by restoring CPT1 activity.

Lung Adenocarcinoma Cells Promote Self-Migration and Self-Invasion by Activating Neutrophils to Upregulate Notch3 Expression of Cancer Cells.

Background: Invasion and migration of cancer cells play a key role in lung cancer progression and metastasis. Tumor-associated neutrophils (TANs) are related to poor prognosis in many types of cancer. However, the role of TANs in lung cancer is controversial. In this study, we investigated the effect of TANs on the invasion and migration of lung adenocarcinoma. Methods: Immunohistochemistry was performed to detect the density of infiltrating TANs and the expression of Notch3 in 100 lung adenocarcinoma tissues. Flow cytometry was used to observe the viability of neutrophils, which were isolated from healthy peripheral blood and then exposed to the supernatant of cultured lung adenocarcinoma cell lines. After treating with tumor-associated neutrophils culture supernatant, NeuCS (supernatant of cultured neutrophils), tumor cells culture supernatant, Medium (serum-free medium), respectively, the migration and invasion of the lung cancer cells before and after transfected by si-Notch3 were detected by transwell assay and wound healing assay. Kaplan-Meier plotter (http://kmplot.com/analysis/index.php?p) was used to analyze the prognostic role of the density of TANs on lung adenocarcinoma and TIMER ((http://cistrome.dfci.harvard.edu/TIMER/) was used to detect the expression of Notch3 on lung adenocarcinoma. Results: The infiltration of TANs was observed in the parenchyma and stroma of the lung adenocarcinoma, the density of TANs was positively related to the TNM stage and negatively related to the differentiation and prognosis. Notch3 expression of cancer cells was negatively related to the tumor differentiation and prognosis. Compared to quiescent neutrophils, the viability of TCCS-activated neutrophils was enhanced. Both migration and invasion of A549 and PC9 cells were significantly promoted by TANs, while after knocking down Notch3, the migration and invasion of the cancer cells were not affected by TANs. Bioinformatics analysis showed that the density of TANs and the expression of Notch3 were related to the poor prognosis. Conclusion: The results indicated that lung adenocarcinoma cells promote self-invasion and self-migration by activating neutrophils to upregulate the Notch3 expression of cancer cells. The density of infiltrating TANs may be a novel marker for the poor prognosis of lung adenocarcinoma. Targeting TANs might be a potential therapeutic strategy for lung cancer treatment.

Comparative carcinogenicity study of a thick, straight-type and a thin, tangled-type multi-walled carbon nanotube administered by intra-tracheal instillation in the rat.

BACKGROUND: Multi-walled carbon nanotubes can be divided into two general subtypes: tangled and straight. MWCNT-N (60 nm in diameter) and MWCNT-7 (80-90 nm in diameter) are straight-type MWCNTs, and similarly to asbestos, both are carcinogenic to the lung and pleura when administered to rats via the airway. Injection of straight-type MWCNTs into the peritoneal cavity also induces the development of mesothelioma, however, injection of tangled-type MWCNTs into the peritoneal cavity does not induce carcinogenesis. To investigate these effects in the lung we conducted a 2-year comparative study of the potential carcinogenicities of a straight-type MWCNT, MWCNT-A (approximately 150 nm in diameter), and a tangled-type MWCNT, MWCNT-B (7.4 nm in diameter) after administration into the rat lung. Crocidolite asbestos was used as the reference material, and rats administered vehicle were used as the controls. Test materials were administered by intra-Tracheal Intra-Pulmonary Spraying (TIPS) once a week over a 7 week period (8 administrations from day 1 to day 50), followed by a 2-year observation period without further treatment. Rats were administered total doses of 0.5 or 1.0 mg MWCNT-A and MWCNT-B or 1.0 mg asbestos. RESULTS: There was no difference in survival between any of the groups. The rats administered MWCNT-A or asbestos did not have a significant increase in bronchiolo-alveolar hyperplasia or tumors in the lung. However, the rats administered MWCNT-B did have significantly elevated incidences of bronchiolo-alveolar hyperplasia and tumors in the lung: the incidence of bronchiolo-alveolar hyperplasia was 0/20, 6/20, and 9/20 in the vehicle, 0.5 mg MWCNT-B, and 1.0 mg MWCNT-B groups, respectively, and the incidence of adenoma and adenocarcinoma combined was 1/19, 5/20, and 7/20 in the vehicle, 0.5 mg MWCNT-B, and 1.0 mg MWCNT-B groups, respectively. Malignant pleural mesothelioma was not induced in any of the groups. CONCLUSIONS: The results of this initial study indicate that tangled-type MWCNT-B is carcinogenic to the rat lung when administered via the airway, and that straight-type MWCNT-A did not have higher carcinogenic potential in the rat lung than tangled-type MWCNT-B.

Pleural translocation and lesions by pulmonary exposed multi-walled carbon nanotubes.

Carbon nanotubes (CNTs) are recently developed tubular nanomaterials, with diameters ranging from a few nanometers to tens of nanometers, and the length reaching up to several micrometers. They can be either single-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs). Due to their nano-scaled structure, CNTs have a unique set of mechanical, electrical, and chemical properties that make them useful in information technologies, optoelectronics, energy technologies, material sciences, medical technologies, and other fields. However, with the wide application and increasing production of CNTs, their potential risks have led to concerns regarding their impact on environment and health. The shape of some types of CNTs is similar to asbestos fibers, which suggests that these CNTs may cause characteristic pleural diseases similar to those found in asbestos-exposed humans, such as pleural plaques and malignant mesothelioma. Experimental data indicate that CNTs can induce lung and pleural lesions, inflammation, pleural fibrosis, lung tumors, and malignant mesothelioma upon inhalation in the experimental animals. In this review, we focus on the potential of MWCNTs to induce diseases similar to those by asbestos, molecular and cellular mechanisms associated with these diseases, and we discuss a method for evaluating the pleural toxicity of MWCNTs.

NK cells contribute to hepatic CD8+ T cell failure in hepatitis B virus-carrier mice after alcohol consumption.

Despite the fact that both Hepatitis B virus (HBV) infection and excessive alcohol consumption represent health problems worldwide, the mechanism by which alcohol affected the progression of HBV-associated liver disease are not completely understood. Therefore, we studied how alcohol affects the development of HBV infection and the role of T cells and NK cells in the antiviral response. Mononuclear cells (MNCs) derived from HBV-carrier mice and wild type (WT) mice were characterized for phenotype by flow cytometry, HBV antigen and gene expression were detected by Radio Immunoassay (RIA), immunohistochemistry and quantitative real-time (qRT)-PCR. Metabolomics changes were detected in mice liver tissue based on ultra high performance liquid tandem chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOFMS). The mice after ethanol consumption shows higher levels of HBV surface Ag (HBsAg), HBV core antigen (HBcAg) and HBV 3.5 kb RNA expression, and a lower level of CD8+ T cells during HBV persistence, with an increased lymphocyte activation gene-3 (LAG-3) expression on CD8+ T cell. In addition, the energy metabolism was downregulated and the oxidative stress was upregulated in the liver tissue. Furthermore, NK cells depletion results in a lower levels of HBV surface Ag (HBsAg) and HBV 3.5 kb RNA expression, and a higher level of CD8+ T cells with reduced expression of LAG-3. In conclusion, alcohol abuse induces CD8+ T cells failure after acute HBV infection, but depletion of NK cells could retore CD8+ T cell activity. Moreover, downregulation of energy metabolism and upregulation of oxidative stress may also contribute to CD8+ T cell failure.

The CRD of Frizzled 7 exhibits chondroprotective effects in osteoarthritis via inhibition of the canonical Wnt3a/ß-catenin signaling pathway.

Osteoarthritis (OA) is a chronic inflammatory joint disease without effective drugs. Frizzled 7 (FzD7) binds its ligand Wnt3a through an extracellular cysteine-rich domain (CRD) to transduce the canonical Wnt/ß-catenin signaling pathway, which has been strongly implicated in OA pathogenesis. Effects of recombinant protein of FzD7 CRD on Wnt/ß-catenin signaling and chondral destruction was evaluated in this study. Firstly, increased protein levels of FzD7, Wnt3a and ß-catenin were detected in human OA cartilage implying that the canonical Wnt/ß-catenin signaling mediated by Wnt3a and FzD7 executes an essential role in OA. Then we showed that FzD7 CRD antagonized the Wnt3a/ß-catenin signaling pathway in a dose-dependent manner by binding Wnt3a. In addition, FzD7 CRD increased the expression of glycosaminoglycans (GAGs), Collagen II, aggrecan and reduced the expression of matrix metalloproteinase (MMP)-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5) in Wnt3a-stimulated human chondrocytes. Furthermore, a single intra-articular injection of the FzD7 CRD was efficacious in destabilization of the medial meniscus (DMM) mouse OA model, significantly improving Osteoarthritis Research Society International (OARSI) histology scores compared to mice treated with PBS. The results indicate that the FzD7 CRD exhibits chondroprotective effects by binding Wnt3a to suppress the Wnt3a/ß-catenin signaling. Targeting the FzD7 CRD may be a novel therapy for the treatment of OA.

IQGAP2 Inhibits Migration and Invasion of Gastric Cancer Cells via Elevating SHIP2 Phosphatase Activity.

Previous studies have shown reduced expression of Src homology 2-containing inositol 5-phosphatase 2 (SHIP2) and its tumor-suppressive role in gastric cancer (GC). However, the precise role of SHIP2 in the migration and invasion of GC cells remains unclear. Here, an IQ motif containing the GTPase-activating protein 2 (IQGAP2) as a SHIP2 binding partner, was screened and identified by co-immunoprecipitation and mass spectrometry studies. While IQGAP2 ubiquitously expressed in GC cells, IQGAP2 and SHIP2 co-localized in the cytoplasm of GC cells, and this physical association was confirmed by the binding of IQGAP2 to PRD and SAM domains of SHIP2. The knockdown of either SHIP2 or IQGAP2 promoted cell migration and invasion by inhibiting SHIP2 phosphatase activity, activating Akt and subsequently increasing epithelial-mesenchymal transition (EMT). Furthermore, knockdown of IQGAP2 in SHIP2-overexpressing GC cells reversed the inhibition of cell migration and invasion by SHIP2 induction, which was associated with the suppression of elevated SHIP2 phosphatase activity. Moreover, the deletion of PRD and SAM domains of SHIP2 abrogated the interaction and restored cell migration and invasion. Collectively, these results indicate that IQGAP2 interacts with SHIP2, leading to the increment of SHIP2 phosphatase activity, and thereby inhibiting the migration and invasion of GC cells via the inactivation of Akt and reduction in EMT.

Scutellarin ameliorates cartilage degeneration in osteoarthritis by inhibiting the Wnt/ß-catenin and MAPK signaling pathways.

Osteoarthritis (OA) is a chronic inflammatory disease that is the basis of cartilage extracellular matrix degeneration and joint inflammation. Scutellarin is an herbal flavonoid glucuronide, isolated from the Chinese traditional herb Erigeron breviscapus, has been reported to have anti-inflammatory effect. Here, we showed that Scutellarin could inhibit inflammation and protects cartilage from degeneration in vitro and in vivo. Scutellarin downregulate the mRNA and protein expression of MMP1, MMP13, and ADAMTS-5, Wnt3a, Frizzled7 and promote the expression of Collagen II and Aggrecan. Moreover, scutellarin inhibit the migration of ß-catenin and phosphorylation of p38 into the nucleus, which may relate to the mediation of the Wnt/ß-catenin and MAPK signaling pathway. Furthermore, scutellarin significantly inhibit the cartilage degradation of DMM-induced OA mice by safranin-O and fast green staining. In conclusion, our study indicates that scutellarin may be a potential drug for the treatment of OA.

Knockdown of SGK1 alleviates the IL-1ß-induced chondrocyte anabolic and catabolic imbalance by activating FoxO1-mediated autophagy in human chondrocytes.

Osteoarthritis (OA) is a common joint disease characterized by the progressive degeneration of articular cartilage with no effective treatment methods available. Cartilage degeneration is closely related to an anabolic and catabolic imbalance in chondrocytes, and accumulating evidence has revealed that autophagy is a crucial protective mechanism that maintains the balance of anabolic and catabolic activities. Therefore, studies aiming to identify additional genes that regulate autophagy as a promising therapeutic strategy for OA are needed. In this study, we analyzed the GSE113825 datasets from Gene Expression Omnibus and validated that serum- and glucocorticoid-regulated kinase 1 (SGK1) was upregulated in OA cartilage. Based on the results from loss-of-function studies, SGK1 silencing promoted the deposition of glycosaminoglycans in interleukin 1 beta (IL-1ß)-treated chondrocytes, and significantly alleviated IL-1ß-induced downregulation of Collagen II and Aggrecan, as well as the upregulation of a disintegrin and metalloproteinase with thrombospondin motifs 5 and matrix metalloproteinase-13. Furthermore, SGK1 knockdown reversed the IL-1ß-induced chondrocyte anabolic and catabolic imbalance by activating autophagy. Moreover, SGK1 directly bound to forkhead box protein O1 (FoxO1) and increased its phosphorylation, which in turn resulted in its translocation from the nucleus. The decreased FoxO1 levels led to a decrease in LC3-I/LC3-II conversion and Beclin-1 levels, subsequently inhibiting autophagosome formation and increasing P62 levels, thus indicating a downregulation of autophagy. Taken together, we identified a critical role of SGK1 in the IL-1ß-induced chondrocyte anabolic and catabolic imbalance, which may represent a potential novel therapeutic target for OA.

Serum levels of the chemokine CCL2 are elevated in malignant pleural mesothelioma patients.

BACKGROUND: Malignant pleural mesothelioma (MPM) is a debilitating disease of the pleural cavity. It is primarily associated with previous inhalation of asbestos fibers. These fibers initiate an oxidant coupled inflammatory response. Repeated exposure to asbestos fibers results in a prolonged inflammatory response and cycles of tissue damage and repair. The inflammation-associated cycles of tissue damage and repair are intimately involved in the development of asbestos-associated cancers. Macrophages are a key component of asbestos-associated inflammation and play essential roles in the etiology of a variety of cancers. Macrophages are also a source of C-C motif chemokine ligand 2 (CCL2), and a variety of tumor-types express CCL2. High levels of CCL2 are present in the pleural effusions of mesothelioma patients, however, CCL2 has not been examined in the serum of mesothelioma patients. METHODS: The present study was carried out with 50 MPM patients and 356 subjects who were possibly exposed to asbestos but did not have disease symptoms and 41 healthy volunteers without a history of exposure to asbestos. The levels of CCL2 in the serum of the study participants was determined using ELISA. RESULTS: Levels of CCL2 were significantly elevated in the serum of patients with advanced MPM. CONCLUSIONS: Our findings are consistent with the premise that the CCL2/CCR2 axis and myeloid-derived cells play an important role in MPM and disease progression. Therapies are being developed that target CCL2/CCR2 and tumor resident myeloid cells, and clinical trials are being pursued that use these therapies as part of the treatment regimen. The results of trials with patients with a similar serum CCL2 pattern as MPM patients will have important implications for the treatment of MPM.

Dopamine delays articular cartilage degradation in osteoarthritis by negative regulation of the NF-κB and JAK2/STAT3 signaling pathways.

BACKGROUND: The progressive loss of cartilage matrix and the breakdown of articular cartilage induced by inflammation play an essential role in osteoarthritis (OA) pathogenesis. Dopamine (DA) is a critical neurotransmitter that is not only involved in controlling exercise, emotion, cognition and neuroendocrine activity but also has anti-inflammatory effects. This study aimed to investigate the effects of DA on OA in vitro and in vivo. METHODS: OA progression was evaluated in a mouse model with surgically induced destabilization of the medial meniscus. Cartilage degradation and OA were analyzed using Safranin O/Fast Green staining. Additionally, qRT-PCR and Western blotting were applied to detect catabolic and anabolic factors involved in cartilage degeneration and underlying mechanisms in OA chondrocytes treated with Interleukin-1ß. RESULTS: In vitro, DA treatment inhibited the production of inducible nitric oxide synthase, cyclooxygenase-2, matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13, while increasing type II collagen and glycosaminoglycan content. Mechanistically, DA reversed IL-1ß-treated nuclear factor-kappa B activation and JAK2/STAT3 phosphorylation. Furthermore, DA suppressed the degradation of cartilage matrix and reduced Osteoarthritis Research Society International scores in the surgically induced OA models. CONCLUSION: DA may be a novel therapeutic agent for OA treatment.