IntroductionPluripotent stem cells are increasingly used to build therapeutic models, including the transplantation of neural progenitors derived from human embryonic stem cells (hESCs). Recently, long non-coding RNAs (lncRNAs), including delta-like homolog 1 gene and the type III iodothyronine deiodinase gene (DLK1-DIO3) imprinted locus-derived maternally expressed gene 3 (MEG3), were found to be expressed during neural development. The deregulation of these lncRNAs is associated with various neurological diseases. The imprinted locus DLK1-DIO3 encodes abundant non-coding RNAs (ncRNAs) that are regulated by differential methylation of the locus. We aim to study the correlation between the DLK1-DIO3-derived ncRNAs and the capacity of hESCs to differentiate into neural lineages.MethodsWe classified hESC sublines into MEG3-ON and MEG3-OFF based on the expression levels of MEG3 and its downstream microRNAs as detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). A cDNA microarray was used to analyze the gene expression profiles of hESCs. To investigate the capacity of neural differentiation in MEG3-ON and MEG3-OFF hESCs, we performed neural lineage differentiation followed by neural lineage marker expression and neurite formation analyses via qRT-PCR and immunocytochemistry, respectively. MEG3-knockdown via small interfering RNA (siRNA) and small hairpin RNA (shRNA) was used to investigate the potential causative effect of MEG3 in regulating neural lineage-related gene expression.ResultsDLK1-DIO3-derived ncRNAs were repressed in MEG3-OFF hESCs compared with those in the MEG3-ON hESCs. The transcriptome profile indicated that many genes related to nervous system development and neural-type tumors were differentially expressed in MEG3-OFF hESCs. Three independent MEG3-knockdown assays using different siRNA and shRNA constructs consistently resulted in downregulation of some neural lineage genes. Lower expression levels of stage-specific neural lineage markers and reduced neurite formation were observed in neural lineage-like cells derived from MEG3-OFF-associated hESCs compared with those in the MEG3-ON groups at the same time points after differentiation.ConclusionsRepression of ncRNAs derived from the DLK1-DIO3 imprinted locus is associated with reduced neural lineage differentiation potential in hESCs.Electronic supplementary materialThe online version of this article (doi:10.1186/scrt535) contains supplementary material, which is available to authorized users.

Tumor microenvironment plays a critical role in regulating tumor progression by secreting factors that mediate cancer cell growth. Stromal fibroblasts can promote tumor growth through paracrine factors; however, restraint of malignant carcinoma progression by the microenvironment also has been observed. The mechanisms that underlie this paradox remain unknown. Here, we report that the tumorigenic potential of breast cancer cells is determined by an interaction between the Robo1 receptor and its ligand Slit2, which is secreted by stromal fibroblasts. The presence of an active Slit2/Robo1 signal blocks the translocation of β-catenin into nucleus, leading to down-regulation of c-myc and cyclin D1 via the PI3K pathway. Clinically, high Robo1 expression in the breast cancer cells correlates with increased survival in breast cancer patients, and low Slit2 expression in the stromal fibroblasts is associated with lymph node metastasis. Together, our findings explain how a specific tumor microenvironment can restrain a given type of cancer cell from progression and demonstrate that both stromal fibroblasts and tumor cell heterogeneity affect breast cancer outcomes.

Purpose: Cysteine-rich 61 (Cyr61/CCN1) is involved in many different types of tumor development and progression. Nonetheless, the role of Cyr61 in human gastric cancer has not yet been fully characterized. Experimental design: We addressed the issue by immunohistochemical staining of 81 gastric adenocarcinoma specimens. Liposome-mediated transfection was used to introduce a Cyr61 expression vector into gastric cancer AGS cell lines. Transfectants were tested in invasion assay by a Boyden chamber. Furthermore, a cyclooxygenase-2 (COX-2) reporter assay and gel mobility shift assay were done to investigate the potential signal pathway of Cyr61. Results: Patients with gastric adenocarcinoma whose tumor displayed high expression of Cyr61 correlated well with aggressive lymph node metastasis, more advanced tumor stage, histologic diffuse type, and early recurrence. Stable transfection of Cyr61 into the AGS cell line strongly enhanced its invasive activity. The overexpression of Cyr61into AGS cells significantly increased the expression of COX-2 mRNA, protein, and enzymatic activity. Gel mobility shift assays further showed that the nuclear factor-nB (NF-nB) pathway was evidently activated in Cyr61-expressing AGS cells. Function-neutralizing antibody to avh3 but not avh5 effectively suppressed Cyr61-mediated NF-nB activation, COX-2 gene expression, and cell invasiveness. Conclusions: Cyr61may contribute to the malignant progression of gastric cancer by promoting tumor cell motility/invasion through up-regulation of the functional COX-2 via an integrin avh3/ NF-nB-dependent pathway.

Background: The early secreted antigenic target 6-kDa protein (ESAT-6) of Mycobacterium tuberculosis (Mtb) not only acts as a key player for virulence but also exhibits a strong immunotherapeutic potential against Mtb. However, little is known about the molecular basis for its potential in immunotherapy. The present study was designed to unravel the role of miRNA-155 in ESAT-6-mediated enhancement of host immunity and apoptosis in macrophages. Methods: Lentivirus-mediated miR-155 sponge and miR-155 and SOCS1 overexpression vectors were developed in macrophages. TLR2- or p65-specific siRNA knockdown was employed to silence TLR2 or p65. Quantitative polymerase chain reaction and western blotting analyses were performed to determine mRNA and protein expression levels, respectively. Macrophage apoptosis was analyzed by flow cytometry. Results: ESAT-6 significantly increased miR-155 expression, which was dependent on TLR2/NF-κB activation in macrophages. Induced expression of miRNA-155 was required for the ESAT-6-mediated protective immune response and macrophage apoptosis. ESAT-6 promoted macrophage apoptosis by targeting the miR-155-SOCS1 pathway. The differential expression levels of TLR2, BIC, and SOCS1 were involved in regulating the immune response in human peripheral blood mononuclear cells of patients with active tuberculosis (TB) and latent TB (LTB). Conclusion: ESAT-6 promotes apoptosis of macrophages via targeting the miRNA155-SOCS1 interaction.

Trastuzumab emtansine (T-DM1) is an antibody drug conjugate (ADC) that was recently approved for the treatment of HER-2-positive metastatic breast cancer. The drug sensitivity of ADCs depends mainly on the internalization efficiency of the drug. Caveolin-1 was shown to promote T-DM1 internalization and enhance drug sensitivity. Whether caveolin-1 can be overexpressed to improve T-DM1 efficacy is interesting and has the potential for clinical application. In this study, diabetes drug metformin was investigated in terms of induction of caveolin-1 expression for increased efficacy of subsequent T-DM1 application. BT-474 cells were pretreated with metformin, followed by combined therapy with metformin and T-DM1. The T-DM1 internalization and drug efficacy were determined, and the protein expressions for signal transduction were also monitored. Caveolin-1 shRNA was applied to suppress endogenous caveolin-1 expression, and the ability of metformin to promote T-DM1 efficacy was investigated. Result showed that in BT-474 cells pretreated with metformin, cellular caveolin-1 overexpression was induced, which then promoted drug efficacy by enhancing T-DM1 internalization. As cellular caveolin-1 was suppressed by shRNA, the effect of metformin-enhanced T-DM1 cytotoxicity was decreased. This study demonstrated that metformin can be applied prior to T-DM1 treatment to improve the clinical efficacy of T-DM1 by enhancing caveolin-1-mediated endocytosis.

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Cysteine-rich 61 (Cyr61; CCN1) plays an important role in tumor development and progression in many kinds of human malignancies. Here, we further show the enforced expression of the Cyr61 gene or treatment with recombinant Cyr61 protein enhanced expression of chemokine receptors CXCR1 and CXCR2 in gastric cancer AGS cells. Attenuation of Cyr61 levels in MKN-45 cells by transfecting with antisense Cyr61 significantly reduced the level of CXCR1 and CXCR2. It is suggested that Cyr61 tightly regulates the downstream genes CXCR1 and CXCR2 in gastric cancer cells. Supportively, reverse transcription -PCR and immunohistochemical analysis of human gastric adenocarcinoma showed that there was a high correlation between the expression level of Cyr61 and CXCR1/CXCR2. The up-regulated functionality of CXCR1 andCXCR2 in Cyr61-overexpressing AGS cells could facilitate their chemotactic migration toward interleukin-8, a physiologic ligand of CXCR1 and CXCR2. In addition, the Cyr61-mediated up-regulation of CXCR1/CXCR2 also contributed to transendothelial migration, as well as intravasation in a chick embryo model. Pharmacologic and genetic approaches revealed that phosphoinositide 3-kinase (PI3K)/Akt, but not extracellular signal-regulated kinase 1/2 or p38, signaling pathway is requisite for the up-regulation of CXCR1/CXCR2 mRNA and protein induced by Cyr61. Function-neutralizing antibody to integrin AvB3, but not A 2 B 1 , effectively abolished Cyr61-elicited Src activation and the subsequent PI3K/ Akt pathway. Antagonists toward integrin AvB3, Src kinase, and PI3K/Akt not only suppressed CXCR1/ CXCR2 elevation but also blocked chemotactic migration induced by Cyr61. In conclusion, we suggest that Cyr61 promotes interleukin-8 -dependent chemotaxis, transendothelial migration, and intravasation by induction of CXCR1/CXCR2 through integrin AvB3/Src/PI3K/Akt -dependent pathway.

Coronavirus disease 2019 (COVID-19) is now pandemic worldwide and has heavily overloaded hospitals in Wuhan City, China during the time between late January and February. We reported the clinical features and therapeutic characteristics of moderate COVID-19 cases in Wuhan that were treated via the integration of traditional Chinese medicine (TCM) and Western medicine. We collected electronic medical record (EMR) data, which included the full clinical profiles of patients, from a designated TCM hospital in Wuhan. The structured data of symptoms and drugs from admission notes were obtained through an information extraction process. Other key clinical entities were also confirmed and normalized to obtain information on the diagnosis, clinical treatments, laboratory tests, and outcomes of the patients. A total of 293 COVID-19 inpatient cases, including 207 moderate and 86 (29.3%) severe cases, were included in our research. Among these cases, 238 were discharged, 31 were transferred, and 24 (all severe cases) died in the hospital. Our COVID-19 cases involved elderly patients with advanced ages (57 years on average) and high comorbidity rates (61%). Our results reconfirmed several well-recognized risk factors, such as age, gender (male), and comorbidities, as well as provided novel laboratory indications (e.g., cholesterol) and TCM-specific phenotype markers (e.g., dull tongue) that were relevant to COVID-19 infections and prognosis. In addition to antiviral/antibiotics and standard supportive therapies, TCM herbal prescriptions incorporating 290 distinct herbs were used in 273 (93%) cases. The cases that received TCM treatment had lower death rates than those that did not receive TCM treatment (17/273 = 6.2% vs. 7/20 = 35%, P = 0.0004 for all cases; 17/77 = 22% vs. 7/9 = 77.7%, P = 0.002 for severe cases). The TCM herbal prescriptions used for the treatment of COVID-19 infections mainly consisted of Pericarpium Citri Reticulatae, Radix Scutellariae, Rhizoma Pinellia, and their combinations, which reflected the practical TCM principles (e.g., clearing heat and dampening phlegm). Lastly, 59% of the patients received treatment, including antiviral, antibiotics, and Chinese patent medicine, before admission. This situation might have some effects on symptoms, such as fever and dry cough. By using EMR data, we described the clinical features and therapeutic characteristics of 293 COVID-19 cases treated via the integration of TCM herbal prescriptions and Western medicine. Clinical manifestations and treatments before admission and in the hospital were investigated. Our results preliminarily showed the potential effectiveness of TCM herbal prescriptions and their regularities in COVID-19 treatment.