SH3GL2 and MMP17 as lung adenocarcinoma biomarkers: a machine-learning based approach.

Objective: Using bioinformatics machine learning methods, our research aims to identify the potential key genes associated with Lung adenocarcinoma (LUAD). Methods: We obtained two gene expression profiling microarrays (GSE68571 and GSE74706) from the public Gene Expression Omnibus (GEO) database at the National Centre for Biotechnology Information (NCBI). The purpose was to identify Differentially Expressed Genes (DEGs) between the lung adenocarcinoma group and the healthy control group. The limma R package in R was utilized for this analysis. For the differential gene diagnosis of lung adenocarcinoma, we employed the least absolute shrinkage and selection operator (LASSO) regression and SVM-RFE screening crossover. To evaluate the performance, ROC curves were plotted. We performed immuno-infiltration analysis using CIBERSORT. Finally, we validated the key genes through qRT-PCR and Western-blot verification, then downregulated MMP17 gene expression, upregulated SH3GL2 gene expression, and performed CCK8 experiments. Results: A total of 32 Differentially Expressed Genes (DEGs) were identified. Two diagnostic marker genes, SH3GL2 and MMP17, were selected by employing LASSO and SVM-RFE machine learning methods. In Lung adenocarcinoma cells, the expression of MMP17 was observed to be elevated compared to normal lung epithelial cells in the control group (P < 0.05). In contrast, a down-regulation of SH3GL2 was found in Lung adenocarcinoma cells (P < 0.05). Finally, we downregulated MMP17 and upregulated SH3GL2 gene expression, then the CCK8 showed that the proliferation of both lung cancer cells was inhibited. Conclusion: SH3GL2 and MMP17 are expected to be potential biomarkers for Lung adenocarcinoma.

Lycium barbarum polysaccharide reverses drug resistance in oxaliplatin-resistant colon cancer cells by inhibiting PI3K/AKT-dependent phosphomannose isomerase.

Objective: Here, we aimed to explore the effect of LBP in combination with Oxaliplatin (OXA) on reversing drug resistance in colon cancer cells through in vitro and in vivo experiments. We also aimed to explore the possible mechanism underlying this effect. Finally, we aimed to determine potential targets of Lycium barbarum polysaccharide (LBP) in colon cancer (CC) through network pharmacology and molecular docking. Methods: The invasion ability of colon cancer cells was assessed using the invasion assay. The migration ability of these cells was assessed using the migration assay and wound healing assay. Cell cycle analysis was carried out using flow cytometry. The expression levels of phosphomannose isomerase (PMI) and ATP-binding cassette transport protein of G2 (ABCG2) proteins were determined using immunofluorescence and western blotting. The expression levels of phosphatidylinositol3-kinase (PI3K), protein kinase B (AKT), B-cell lymphoma 2 (Bcl-2), and BCL2-Associated X (Bax) were determined using western blotting. Forty BALB/c nude mice purchased from Weitong Lihua, Beijing, for the in vivo analyses. The mice were randomly divided into eight groups. They were administered HCT116 and HCT116-OXR cells to prepare colon cancer xenograft models and then treated with PBS, LBP (50 mg/kg), OXA (10 mg/kg), or LBP + OXA (50 mg/kg + 10 mg/kg). The tumor weight and volume of treated model mice were measured, and organ toxicity was evaluated using hematoxylin and eosin staining. The expression levels of PMI, ABCG2, PI3K, and AKT proteins were then assessed using immunohistochemistry. Moreover, PMI and ABCG2 expression levels were analyzed using immunofluorescence and western blotting. The active components and possible targets of LBP in colon cancer were explored using in silico analysis. GeneCards was used to identify CC targets, and an online Venn analysis tool was used to determine intersection targets between these and LBP active components. The PPI network for intersection target protein interactions and the PPI network for interactions between the intersection target proteins and PMI was built using STRING and Cytoscape. To obtain putative targets of LBP in CC, we performed GO function enrichment and KEGG pathway enrichment analyses. Results: Compared with the HCT116-OXR blank treatment group, both invasion and migration abilities of HCT116-OXR cells were inhibited in the LBP + OXA (2.5 mg/mL LBP, 10 µΜ OXA) group (p < 0.05). Cells in the LBP + OXA (2.5 mg/mL LBP, 10 µΜ OXA) group were found to arrest in the G1 phase of the cell cycle. Knockdown of PMI was found to downregulate PI3K, AKT, and Bcl-2 (p < 0.05), while it was found to upregulate Bax (p < 0.05). After treatment with L. barbarum polysaccharide, 40 colon cancer subcutaneous tumor models showed a decrease in tumor size. There was no difference in the liver index after LBP treatment (p > 0.05). However, the spleen index decreased in the OXA and LBP + OXA groups (p < 0.05), possibly as a side effect of oxaliplatin. Immunohistochemistry, immunofluorescence, and western blotting showed that LBP + OXA treatment decreased PMI and ABCG2 expression levels (p < 0.05). Moreover, immunohistochemistry showed that LBP + OXA treatment decreased the expression levels of PI3K and AKT (p < 0.05). Network pharmacology analysis revealed 45 active LBP components, including carotenoids, phenylpropanoids, quercetin, xanthophylls, and other polyphenols. It also revealed 146 therapeutic targets of LBP, including AKT, SRC, EGFR, HRAS, STAT3, and MAPK3. KEGG pathway enrichment analysis showed that the LBP target proteins were enriched in pathways, including cancer-related signaling pathways, PI3K/AKT signaling pathway, and IL-17 signaling pathways. Finally, molecular docking experiments revealed that the active LBP components bind well with ABCG2 and PMI. conclusion: Our in vitro experiments showed that PMI knockdown downregulated PI3K, AKT, and Bcl-2 and upregulated Bax. This finding confirms that PMI plays a role in drug resistance by regulating the PI3K/AKT pathway and lays a foundation to study the mechanism underlying the reversal of colon cancer cell drug resistance by the combination of LBP and OXA. Our in vivo experiments showed that LBP combined with oxaliplatin could inhibit tumor growth. LBP showed no hepatic or splenic toxicity. LBP combined with oxaliplatin could downregulate the expression levels of PMI, ABCG2, PI3K, and AKT; it may thus have positive significance for the treatment of advanced metastatic colon cancer. Our network pharmacology analysis revealed the core targets of LBP in the treatment of CC as well as the pathways they are enriched in. It further verified the results of our in vitro and in vivo experiments, showing the involvement of multi-component, multi-target, and multi-pathway synergism in the drug-reversing effect of LBP in CC. Overall, the findings of the present study provide new avenues for the future clinical treatment of CC.

Umbilical cord mesenchymal stem cell-derived exosomes inhibits fibrosis in human endometrial stromal cells via miR-140-3p/FOXP1/Smad axis.

Endometrial fibrosis is the histologic appearance of intrauterine adhesion (IUA). Emerging evidences demonstrated umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-exo) could alleviate endometrial fibrosis. But the specific mechanism is not clear. In this study, we explored the effect of UCMSC-exo on endometrial fibrosis, and investigated the possible role of miR-140-3p/FOXP1/Smad axis in anti-fibrotic properties of UCMSC-exo. UCMSC-exo were isolated and identified. Transforming growth factor-ß (TGF-ß) was used to induce human endometrial stromal cell (HESC) fibrosis. Dual luciferase assay was performed to verify the relationship between miR-140-3p and FOXP1. The expressions of fibrotic markers, SIP1, and p-Smad2/p-Smad3 in HESCs stimulated with UCMSC-exo were detected by western blot. In addition, the effects of miR-140-3p mimic, miR-140-3p inhibitor and FOXP1 over-expression on endometrial fibrosis were assessed. The isolated UCMSC-exo had a typical cup-shaped morphology and could be internalized into HESCs. The expressions of fibrotic markers were significantly increased by TGF-ß, which was reversed by UCMSC-exo. MiR-140-3p in UCMSC-exo ameliorated TGf-ß-induced HESCs fibrosis. FOXP1 was identified as the direct target of miR-140-3p, which could inversely regulate miR-140-3p's function on HESCs fibrosis. Furthermore, we demonstrated that miR-140-3p in UCMSC-exo regulated Smad signal pathway to exert the anti-fibrotic effect in HESCs. The anti-fibrotic effect of UCMSC-derived exosomes against HESC fibrosis was at least partially achieved by miR-140-3p/FOXP1/Smad axis.

[IL-1ß inhibits macrophage M2 polarization by down-regulating CD200 expression in human umbilical cord mesenchymal stem cells].

Objective To investigate the regulation of IL-1ß on the expression of CD200 in human umbilical cord mesenchymal stem cells (hUC-MSCs), its role in macrophage polarization and the underlying mechanism. Methods hUC-MSCs were isolated and cultured in serum-free medium. Morphological observation and the expressions of CD73, CD90, CD105, CD14, CD34, CD45 and HLA-DR were detected by flow cytometry to confirm the properties of mesenchymal stem cells. hUC-MSCs were treated with IL-1ß at the final concentration of 20 ng/mL for 24 hours. The proportion of CD200 positive cells was measured by flow cytometry. Real-time quantitative PCR and Western blot analysis were used to detect CD200 mRNA and protein expression levels. hUC-MSCs infected with CD200 overexpression (OE-CD200) and its negative control (OE-NC) lectin virus were treated with IL-1ß and co-cultured with PMA-activated THP-1 macrophages. The proportion of CD11c and CD206 positive cells was measured by flow cytometry. hUC-MSCs were treated with IL-1ß in combination with PD98059, and the expression of MAPK signaling pathway-related proteins and its effect on CD200 expression were detected by Western blot analysis. Results IL-1ß significantly down-regulated the expression of CD200 protein and the proportion of CD200 positive cells. Overexpression of CD200 significantly up-regulated the expression of CD200 in hUC-MSCs, and increased the proportion of CD206-positive macrophages. IL-1ß activated the ERK1/2 signaling pathway in hUC-MSCs, and PD98059 up-regulated the expression of CD200 protein in hUC-MSCs treated with IL-1ß. Conclusion IL-1ß inhibits the expression of CD200 by activating ERK1/2 signaling pathway, and reduces the immunosuppressive effect of hUC-MSCs on regulating the M2-type polarization of macrophages.

Catalytic pyrolysis of liquor-industry waste: Product and mechanism analysis.

The effects of three catalysts, namely Ni/γ-Al2O3, Fe/γ-Al2O3, and Mg/γ-Al2O3, on the three-phase products of liquor-industry waste pyrolysis were investigated in this study. Results indicated that the catalytic performance of Ni/γ-Al2O3 outperformed those of Fe/γ-Al2O3 and Mg/γ-Al2O3 significantly. The application of Ni/γ-Al2O3 facilitated the reformation of pyrolysis volatiles, leading to increased yields of H2 (174.1 mL/g), CH4 (80.7 mL/g), and CO (88.2 mL/g) by 980.00 %, 133.24 %, and 83.37 %, respectively. compared to catalyst-free conditions. The Ni/γ-Al2O3 also increased the low-level calorific value of biogas by 109.3 % compared to that under non-catalyst conditions. Moreover, Ni/γ-Al2O3 enhanced the relative concentrations of hydrocarbons in tar by 23.15 % while reducing the relative concentrations of O-species by 15.73 % compared to catalyst-free conditions through induced deoxygenation, decarboxylation, decarbonylation reactions as well as efficient steam reforming processes for tar and syngas upgrading purposes. Thus, incorporating Ni/γ-Al2O3 into the pyrolysis process represents a renewable approach for waste-to-energy conversion.

Autophagy inhibition restores CD200 expression under IL-1ß microenvironment in placental mesenchymal stem cells of fetal origin and improves its pulmonary fibrosis therapeutic potential.

BACKGROUND: Mesenchymal stem cells (MSCs) are promising remedies for various inflammatory disease including pulmonary fibrosis (PF). However, the properties of MSCs in PF pathological microenvironment remain unclear. In this study, the efficacy of autophagy in placental mesenchymal stem cells of fetal origin (fPMSCs) in either IL-1ß treatment or BLM induced pulmonary fibrosis mice model was examined. METHODS: The characteristic of fPMSCs was identified by morphological observation, flow cytometry and differentiation potential. In vitro experiments, fPMSCs were stimulated with IL-1ß, to mimic inflammatory microenvironment of pulmonary fibrosis. The immunosuppressive properties and autophagic function in fPMSCs treated with IL-1ß were evaluated by both macrophage cells THP-1 activation and the expression of CD200 situation, autophagy marker and MAPK signaling pathway. The in vivo anti-fibrotic activity of fPMSCs interfering autophagy was evaluated by using BLM induced pulmonary fibrosis mice model. RESULTS: fPMSCs belonged to CD73+CD90+CD105+/CD14- CD34-CD45-HLA-DR- cells, and capable differentiation to adipogenic, osteogenic and chondrogenic cells. In addition, immunoinhibitory activity of fPMSCs for macrophage was restrained by IL-1ß treatment in CD200 dependent manner. Suppression of autophagy by sh-Atg5 lentivirus increased the expression of CD200 and ratio of CD200 positive fPMSCs, and enhanced fPMSCs immunosuppression for THP-1 activation. Mechanistically, IL-1ß induced autophagy regulated by p38 signaling cascade. In vivo, autophagy inhibition induced by Atg5 knockdown in fPMSCs resulted in strengthening antifibrotic effects on PF mice model. CONCLUSIONS: Collectively, autophagy derived from inflammatory microenvironment hampered the immunoinhibitory properties of MSCs. Based on this, adjustment of autophagy may be a valid approach to facilitate their immunomodulatory and anti-fibrotic efficacy.

Flavokawain B Weakens Gastric Cancer Progression via the TGF-ß1/SMAD4 Pathway and Attenuates M2 Macrophage Polarization.

This study was designed to observe the treatment effects of flavokawain B (FKB) on gastric cancer both in SGC-7901 cells and nude mice. When SGC-7901 cells were exposed to 10 µg/mL FKB, cellular proliferative and apoptotic capacities and cell cycle were detected utilizing CCK-8 and flow cytometry assays. The results showed that FKB treatment induced cell apoptosis and G2/M arrest and suppressed cell proliferation for SGC-7901 cells. Western blot results showed that FKB upregulated proapoptotic proteins as well as downregulated antiapoptotic and cell cycle-related proteins in SGC-7901 cells. SMAD4, TGF-ß1, and TSPAN12 proteins were tested in FKB-induced SGC-7901 cells. Following exposure to FKB, SMAD4, TGF-ß1, and TSPAN12 expression was augmented in SGC-7901 cells. si-SMAD4 transfection weakened cell apoptosis and accelerated cell proliferation. Furthermore, FKB reversed the change in apoptotic and cell cycle-related proteins induced by si-SMAD4. A nude mouse tumorigenesis model was constructed, which was treated by FKB. In the nude mouse tumorigenesis model, FKB activated the TSPAN12 expression and TGF-ß1/SMAD4 pathway. Also, FKB treatment prolonged the survival time of nude mice and lowered tumor weight. iNOS and CD86 expression was significantly enhanced, and Arg-1 and CD206 expression was significantly decreased in THP-1 cells cultured in conditioned media from FKB-treated SGC-7901 cells. Additionally, FKB-treated SGC-7901 cells weakened macrophage migration. Collectively, this evidence suggested that FKB accelerated apoptosis and suppressed the proliferation of gastric cancer cells and attenuated M2 macrophage polarization, thereby exerting an anticancer effect on gastric cancer.

Oxymatrine promotes hypertrophic scar repair through reduced human scar fibroblast viability, collagen and induced apoptosis via autophagy inhibition.

Scars are common complications of burns and trauma, resulting in mental trauma, physical pain, and a heavy financial burden for patients. Specific and effective anti-scarring drugs are lacking in clinical practice. Phytochemicals are easily accessible, low in toxicity, and have various biological and pharmacological properties. Oxymatrine is a phytochemical that regulates autophagy networks. Autophagy is closely related to the maintenance, activity, differentiation, and life-death of skin fibroblasts during wound repair, which results in pathological scars. We hypothesised that oxymatrine may promote hypertrophic scar repair by inhibiting fibroblast autophagy. In vitro studies showed that inhibition of autophagy by oxymatrine decreased viability and collagen metabolism, and increased apoptosis of human scar fibroblasts (HSFs). In vivo studies showed that inhibition of autophagy by oxymatrine promoted scar repair, resulting in a significantly improved final outcome of the hypertrophic scars, a smaller scar area, decreased epidermal and dermal thickness, and a significant downregulation of CK10, P63, collagen I, α-SMA, and TGF-ß1. In summary, oxymatrine promoted hypertrophic scar repair by decreasing HSF viability and collagen, and inducing apoptosis via autophagy inhibition. This study provides a new perspective on the mechanism of hypertrophic burn scar formation, as well as key scientific data for the application of the phytochemical oxymatrine as a new method for the prevention and treatment of hypertrophic scars.

Depiction of Aging-Based Molecular Phenotypes With Diverse Clinical Prognosis and Immunological Features in Gastric Cancer.

OBJECTIVE: Aging acts as a dominating risk factor for human cancers. Herein, we systematically dissected the features of transcriptional aging-relevant genes in gastric cancer from multiple perspectives. METHODS: Based on the transcriptome profiling of prognostic aging-relevant genes, patients with gastric cancer in The Cancer Genome Atlas (TCGA) stomach adenocarcinoma (TCGA-STAD) cohort were clustered with a consensus clustering algorithm. Mutational landscape and chemotherapeutic responses were analyzed and immunological features (immunomodulators, immune checkpoint molecules, cancer immunity cycle, and tumor-infiltrating immune cells) were systematically evaluated across gastric cancer. Weighted gene co-expression network (WGCNA) was conducted for screening aging molecular phenotype-relevant genes, and key genes were identified with Molecular Complex Detection (MCODE) analyses. Expressions of key genes were examined in 20 paired tumors and controls with RT-qPCR and Western blotting. Proliferation and apoptosis were investigated in two gastric cancer cells under MYL9 deficiency. RESULTS: Three aging-based molecular phenotypes (namely, C1, C2, and C3) were conducted in gastric cancer. Phenotype C1 presented the most prominent survival advantage and highest mutational frequencies. Phenotype C2 indicated low responses to sorafenib and gefitinib, while C3 indicated low responses to vinorelbine and gemcitabine. Additionally, phenotype C2 was characterized by enhanced immune and stromal activation and an inflamed tumor microenvironment. Seven aging molecular phenotype-relevant key genes (ACTA2, CALD1, LMOD1, MYH11, MYL9, MYLK, and TAGLN) were identified, which were specifically upregulated in tumors and in relation to dismal prognosis. Among them, MYL9 deficiency reduced proliferation and enhanced apoptosis in gastric cancer cells. CONCLUSION: Collectively, aging-based molecular subtypes may offer more individualized therapy recommendations and prognosis assessment for patients in distinct subtypes.

The role of Nrf2/PIWIL2/purine metabolism axis in controlling radiation-induced lung fibrosis.

NF-E2-related factor 2 (Nrf2) is a key transcription factor recently implicated in the control of radiation-induced lung fibrosis (RILF). However, the molecular mechanism of Nrf2 in the pathogenesis of RILF is still unclear. The purpose of this study was to evaluate the regulatory effect and mechanism of Nrf2 in the pathogenesis of RILF. The effects of different Nrf2 expression levels on RILF were explored in vitro and in vivo. The RILF model of Nrf2 knockout mice was established for in vivo study. In the study of the mechanism of action, ChIP-seq assay and metabolomics analysis were performed. The discovered mechanism of Nrf2-mediated RILF alleviation was further validated in vitro and in vivo. We found that overexpression of Nrf2 significantly alleviated the fibrosis caused by irradiation in vivo and in vitro. Conversely, Nrf2 silencing strongly aggravated the development of RILF. Mechanistically, Nrf2 signaling increased the expression of piwi-like RNA-mediated gene silencing 2 (PIWIL2), leading to the alteration of purine metabolism and contributing to the relief of RILF. These results suggest that Nrf2 promotes the attenuation of RILF in vivo and in vitro by directly targeting PIWIL2 and activating purine metabolism.

LncRNA FLJ33360 accelerates the metastasis in hepatocellular carcinoma by targeting miRNA-140/MMP9 axis.

This study aims to detect expression level of long non-coding RNA (lncRNA) FLJ33360 in hepatocellular carcinoma (HCC) and its regulatory effects on accelerating malignant progression of HCC. Expression levels of FLJ33360 in 29 matched HCC tissues and paracancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). After transfection of sh-FLJ33360#1 in Bel-7402 and HepG2 cells, changes in migratory and invasive capacities were evaluated by Transwell and wound healing assay. Potential miRNAs targeting FLJ33360 were verified. The correlation between expression levels of FLJ33360 and miRNA-140 in HCC tissues was determined. At last, potential influences of FLJ33360/miRNA-140 regulatory loop on HCC phenotypes were determined by rescue experiments. FLJ33360 was upregulated in HCC tissues relative to paracancerous ones. After knockdown of FLJ33360, migratory and invasive capacities in Bel-7402 and HepG2 cells were attenuated. There were five miRNA candidates predicted to bind FLJ33360, and miRNA-140 was the most differentially expressed by FLJ33360 regulation. Dual-luciferase reporter gene assay confirmed the binding between FLJ33360 and miRNA-140. Besides, their expression levels were negatively correlated in HCC tissues. Moreover, knockdown of miRNA-140 could stimulate metastatic ability in HCC. At last, rescue experiments verified the involvement of miRNA-140 in FLJ33360-regulated HCC progression. LncRNA FLJ33360 is upregulated in HCC. It accelerates the metastasis of HCC through targeting miRNA-140/MMP9 axis.

[Hepatocyte growth factor paracrined from human placental mesenchymal stem cells of fetal origin alleviates the injury of human pulmonary microvascular endothelial cells induced by lipopolysaccharide].

Objective To investigate the protective function of paracrine hepatocyte growth factor (HGF) derived from human placental mesenchymal stem cells of fetal origin (hfPMSCs) cultured in serum-free medium against endothelial cell injury induced by lipopolysaccharide (LPS). Methods The hfPMSCs were cultured in serum-free medium and surface antigen CD73, CD90, CD105, CD14, CD34, CD45 and HLA-DR were analyzed by flow cytometry. Using TranswellTM co-culture system [human pulmonary microvascular endothelial cell (HPMECs) were added into the upper chambers of TranswellTM inserts, and hfPMSCs were added into the lower chambers of TranswellTM inserts], the influence of hfPMSCs paracrine HGF on the permeability of HPMECs in LPS condition was identified. Then four different co-culture conditions were used as follows: 100 ng/mL LPS treatment group; hfPMSCs co-culture group; HGF neutralization group; HPMECs normal control. After 100 µg FITC-dextran was added into the upper chambers of TranswellTM inserts, the effect of stain permeability was detected by fluorescence microplate reader. The expression of VE-cadherin, caveolin-1 and cleaved caspase-3, cleaved PARP-1 in HPMECs were measured by Western blot analysis. Results The hfPMSCs showed the classic morphology of mesenchymal stem cells and expressed the surface markers CD73, CD90 and CD105, but did not express CD14, CD34, CD45 and HLA-DR. Compared with LPS treatment group, the co-culture with hfPMSCs dramatically inhibited the permeability of HPMECs, significantly up-regulated the expression of VE-cadherin, and reduced the expression of caveolin-1, cleaved caspase-3, cleaved PARP1. In contrast, neutralizing HGF with anti-HGF antibody reversed the above effects of hfPMSCs-HPMECs co-culture. Conclusion Owing to paracrine HGF, hfPMSCs possess the capability to availably inhibit the permeability of HPMECs induced by LPS.

Thalidomide (THD) alleviates radiation induced lung fibrosis (RILF) via down-regulation of TGF-ß/Smad3 signaling pathway in an Nrf2-dependent manner.

Radiation-induced lung fibrosis (RILF) is a complication of radiotherapy in thoracic cancer patients. Thalidomide (THD) has a therapeutic effect on fibrotic and inflammatory disorders. The purpose of the current study was to investigate the therapeutic effect of THD on RILF in mice and better understand the underlying regulatory mechanisms of the therapeutic effect. We found that THD mitigated the fibrosis caused by irradiation in mice. The action of THD on RILF was related to the elevation of low levels reactive oxygen species (ROS), which inhibited the transforming growth factor­ß (TGF­ß)/Smad3 signaling pathway through activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Analysis of the therapeutic effect of THD using Nrf2-/- mouse model confirmed the role of Nrf2 in vivo. In addition, no radioprotective effect of THD on thoracic cancer cell lines was observed. In conclusion, these data showed that THD attenuated RILF in mice, which was mediated by Nrf2-dependent down-regulation of the TGF-ß/Smad3 pathway, suggesting THD as a potential novel agent for RILF prevention.

Wnt5a Increases Properties of Lung Cancer Stem Cells and Resistance to Cisplatin through Activation of Wnt5a/PKC Signaling Pathway.

The development of chemoresistance to cisplatin regimens causes a poor prognosis in patients with advanced NSCLC. The role of noncanonical Wnt signaling in the regulation of properties of lung cancer stem cells and chemoresistance was interrogated, by accessing capacities of cell proliferation, migration, invasion, and clonogenicity as well as the apoptosis in A549 cell lines and cisplatin-resistant A549 cells treated with Wnt5a conditional medium or protein kinase C (PKC) inhibitor GF109203X. Results showed that the noncanonical Wnt signaling ligand, Wnt5a, could promote the proliferation, migration, invasion, and colony formation in A549 lung adenocarcinoma cells and cisplatin-resistant A549/DDP cells and increase the fraction of ALDH-positive cell in A549/DDP cells. An exposure of cells to Wnt5a led to a significant reduction of A549/DDP cell apoptosis but not A549 cells. An addition of GF109203X could both strikingly increase the baseline apoptosis and resensitize the Wnt5a-inhibited cell apoptosis. Interestingly, an inhibition of Wnt/PKC signaling pathway could reduce properties of lung cancer stem cells, promote cell apoptosis, and resensitize cisplatin-resistant cells to cisplatin via a caspase/AIF-dependent pathway. These data thus suggested that the Wnt5a could promote lung cancer cell mobility and cisplatin-resistance through a Wnt/PKC signaling pathway and a blockage of this signaling may be an alternative therapeutic strategy for NSCLC patients with resistance to chemotherapies.

[Human placental mesenchymal stem cells of fetal origin relieves mouse pulmonary fibrosis via downregulating MyD88 and TGF-ß signaling pathway].

Objective To investigate the therapeutic effect and mechanism of human placental mesenchymal stem cells of fetal origin (hfPMSCs) cultured in serum-free medium on mouse pulmonary fibrosis induced by bleomycin treatment. Methods Human hfPMSCs were cultured and identified by flow cytometry. Fifteen 6-week-old male SPF C57BL/6J mice were divided into 3 groups: bleomycin treatment group, hfPMSCs transplantation group and negative control group. Pulmonary fibrosis model was induced in the mice of bleomycin treatment group and hfPMSCs transplantation group with bleomycin (1 µg/L, 50 µL) via intratracheal instillation. The mice in negative control group were instilled with PBS (50 µL) through the same manner of the other two groups. Three days post-modelling, 200 µL containing 5×105 hfPMSCs were injected into hfPMSCs transplantation group via tail vein. All the mice were sacrificed at day 21 after modeling in batch. Lung tissues were collected for analyzing the pathological changes by HE staining and Masson staining as well as detecting collagen content. The total protein of lung tissues was extracted for observing the expressions of myeloid differentiation factor 88 (MyD88) and transforming growth factor-ß (TGF-ß); the level of TGF-ß in sera was determined by Western blotting. Results The hfPMSCs possessed the morphology of mesenchymal stem cells and expressed the surface markers CD73, CD90 and CD105, but did not express CD14, CD34 and CD45. HE and Masson staining showed that hfPMSCs transplantation significantly reduced the degree of pulmonary fibrosis compared with bleomycin treatment group. The collagen content and the expression levels of MyD88 and TGF-ß in bleomycin treatment group were obviously higher than those in hfPMSCs transplantation group and negative control group. Conclusion hfPMSCs possess the capability of alleviating pulmonary fibrosis by down-regulating the expressions of MyD88 and TGF-ß.

[Comparison of immunosuppressive effects between human placental MSCs derived from fetal and maternal origins on the rejection of allogenic skin grafts in mice].

OBJECTIVE: To compare the immunosuppressive effects of maternal and fetal placental mesenchymal stem cells (mPMSCs and fPMSCs, respectively) on the rejection of allogenic skin transplants in mice, and further to investigate the mechanism underlying this suppression. METHODS: The mPMSCs and fPMSCs were isolated from human term placentas. The expressions of cell surface markers were detected by flow cytometry. Cell proliferation capacity was characterized by MTT colorimetric assay. CD200 protein expressed on fPMSCs was neutralized with streaming monoclonal antibodies, and mPMSCs were infected with adenovirus expression vector carrying CD200 cDNA. For skin transplantation, 60 C57BL/6 mice were randomly divided into 6 groups as skin transplant recipients, and ICR mice served as skin donors. After establishment of the allogenic skin transplants, recipient mice of the 6 groups were intravenous injected respectively with PBS, mPMSCs, fPMSCs, fPMSCs combined with anti-CD200 antibodies, mPMSCs with CD200 expressing vectors, and mPMSCs with empty vectors. The conditions and survival time of the skin grafts were inspected daily, and the expressions of interleukin 17 (IL-17), interferon γ (IFN-γ), tumor necrosis factor α (TNF-α) and interleukin 12 (IL-12) in blood and spleen were measured at the end of the study by ELISA and reverse transcription PCR. RESULTS: The majority (>70%) of fPMSCs were detected CD200 positive, while only a minor fraction (about 2%) of CD-200 positive cells were seen in mPMSCs. In the allogenic skin graft mice, the graft survival time in both mPMSCs- and fPMSCs-treated groups were significantly longer than that in PBS group [(5.6±1.17) days], while the fPMSCs group [(10.6±1.43) days] was more dominant than mPMSCs group [(7.7±1.42) days]. Neutralizing anti-CD200 antibody reduced the graft survival [(8.2±1.14) days] of the fPMSCs group to the level of that in mPMSCs group, while enforced expression of CD200 increased the graft survival [(10.7±1.34) days] of the mPMSCs group to the level of the fPMSCs group. The empty vector-transfected mPMSCs showed a similar effect on graft survival [(7.8±1.32) days] as that in mPMSCs group, longer than PBS group but shorter than fPMSCs and mPMSCs combined with CD200 groups. Comparing with PBS group, the expressions of IL-17, IFN-γ and TNF-α were significantly reduced in mPMSCs and fPMSCs groups. The reduction of these cytokine expressions in the fPMSCs group was neutralized when anti-CD200 antibody was applied, while this reduction in the mPMSCs-treated mice was further enhanced when the mPMSCs were enforced to express CD200. CONCLUSION: The immunosuppressive effect of fPMSCs on the rejection of allogenic skin transplantation was higher than that of mPMSCs, and this difference was partially contributed by CD200 signaling pathway. The mechanism of this suppression may mediate the inhibition of IL-17, IFN-γ, TNF-α and IL-12 expressions. The fPMSCs may be a suitable choice for immunosuppression on skin transplantation.

Alteration of histone acetylation pattern during long-term serum-free culture conditions of human fetal placental mesenchymal stem cells.

Increasing evidence suggests that the mesenchymal stem cells (MSCs) derived from placenta of fetal origin (fPMSCs) are superior to MSCs of other sources for cell therapy. Since the initial number of isolated MSCs is limited, in vitro propagation is often required to reach sufficient numbers of cells for therapeutic applications, during which MSCs may undergo genetic and/or epigenetic alterations that subsequently increase the probability of spontaneous malignant transformation. Thus, factors that influence genomic and epigenetic stability of MSCs following long-term expansions need to be clarified before cultured MSCs are employed for clinical settings. To date, the genetic and epigenetic stability of fPMSCs after long-term in vitro expansion has not been fully investigated. In this report, alterations to histone acetylation and consequence on the expression pattern of fPMSCs following in vitro propagation under serum-free conditions were explored. The results show that fPMSCs maintain their MSC characteristics before they reached a senescent state. Furthermore, acetylation modification patterns were changed in fPMSCs along with gradually increased global histone deacetylase (HDAC) activity and expression of HDAC subtypes HDAC4, HDAC5 and HDAC6, as well as a down-regulated global histone H3/H4 acetylation during in vitro culturing. In line with the acetylation alterations, the expression of oncogenes Oct4, Sox2 and TERT were significantly decreased over the propagation period. Of note, the down-regulation of Oct4 was strongly associated with changes in acetylation. Intriguingly, telomere length in fPMSCs did not significantly change during the propagating process. These findings suggest that human fPMSCs may be a safe and reliable resource of MSCs and can be propagated under serum-free conditions with less risk of spontaneous malignancy, and warrants further validation in clinical settings.

Placental mesenchymal stem cells of fetal origin deposit epigenetic alterations during long-term culture under serum-free condition.

OBJECTIVE: Fetal placental mesenchymal stem cells (fPMSCs) have shown promising cell therapy potentials. However, their genetic and epigenetic stability during in vitro propagation has not been well studied. We thus interrogated the methylation alterations and tumorigenicity of fPMSCs after in vitro expansion using serum-free medium. RESEARCH DESIGN AND METHODS: The properties of fPMSCs cultured in a serum-free medium at passage 3 and passage 8 were ascertained by determining their MSC markers, proliferative capacity, chromosomal stability, activity of global DNA methyltransferases and methylation profile. Their potential of malignant transformation was also evaluated in a severe combined immunodeficiency (SCID) murine model. RESULTS: The fPMSCs could maintain their MSC characteristics but quickly reached a senescent state of proliferation during in vitro expansion. 246 genes with differential DNA methylation of promoters were identified, along with a significantly downregulated global DNA methyltransferase activity. The genes associated with aging and tumorigenesis had a significantly demethylated tendency over in vitro propagation. However, the deposition of epigenetic alterations did not translate into malignant transformation in SCID mice. CONCLUSION: The fPMSCs cultured in serum-free medium have a tendency to deposit methylation modifications over in vitro expansion, therefore the detection of genetic and/or epigenetic alterations is necessary for fPMSCs before they are employed for clinical uses.

Placental mesenchymal stem cells of fetal and maternal origins demonstrate different therapeutic potentials.

INTRODUCTION: Therapeutic potentials of mesenchymal stem cells (MSCs) from different sources have been evaluated in pre-clinical and clinical settings. Although MSCs from different sources share MSC-specific characteristics and functions, inconsistent or controversial results of pre-clinical and clinical applications of such cells are frequently reported. This may be partially due to the fact that MSCs isolated from different origins may differentially express some functions not typical for MSCs, and hence have different therapeutic potentials. The aim of this study is to investigate the differences in human placental MSCs (P-MSCs) of fetal and maternal origins in the aspects of clinical importance. METHODS: P-MSCs of fetal and maternal origins isolated from normal term placentas were characterized for their typical phenotype as well as their expression of receptors and growth factors of clinic interests. P-MSCs that preferentially express hepatocyte growth factor (HGF) and CD200 were evaluated for their therapeutic potentials in models of angiogenesis and allogeneic skin transplantation, in comparison with their HGF and CD200 negative partners. RESULTS: Although all P-MSCs express typical MSC phenotype, fetal but not maternal P-MSCs express high levels of CD200 and HGF. Compared with HGF and CD200 negative P-MSCs, HGF and CD200 positive cells demonstrated significantly high potentials in promoting angiogenesis in vitro and increasing immunosuppressive function in vivo. These therapeutic potentials were at least in part due to their differences in HGF and CD200 expression, respectively. CONCLUSIONS: We conclude that MSC origins may have significant impact on the therapeutic potentials of such cells, and should be taken into consideration in clinical applications.

Apoptosis induced by PGC-1ß in breast cancer cells is mediated by the mTOR pathway.

The peroxisome proliferator-activated receptor-γ (PPAR-γ) coactivator-1ß (PGC-1ß) is a well-established regulator of mitochondrial biogenesis. However, the underlying mechanism of PGC-1ß action remains elusive. This study reveals that knockdown of endogenous PGC-1ß by short-hairpin RNA (shRNA) leads to a decrease in the expression of mammalian target of rapamycin (mTOR) pathway-related genes in MDA-MB-231 cells. After knockdown of PGC-1ß, phosphorylation of AMP-activated protein kinase (AMPK), phosphorylation of Rictor on Thr1135, Raptor and S6 protein was inhibited. However, Akt phosphorylation on Ser473 was upregulated and cell apoptosis occurred. In particular, we demonstrate that the levels of PGC-1ß and mTOR correlated with overall mitochondrial activity. These results provide new evidence that cell apoptosis is orchestrated by the balance between several signaling pathways, and that PGC-1ß takes part in these events in breast cancer cells mediated by the mTOR signaling pathway.