1. POSSIBLE REGULATION OF LDL-RECEPTOR BY NARINGENIN IN HEPG2 HEPATOMA CELL LINE.
作者: Nora A Bawazeer.;Hani Choudary.;Mazin A Zamzami.;Wesam H Abdulaal.;Mustafa Zeyadi.;Ashwag ALbukhari.;Bruce Middleton.;Said S Moselhy.
来源: Afr J Tradit Complement Altern Med. 2017年14卷1期278-287页
High plasma concentration of low-density lipoprotein cholesterol (LDL-c) plays a significant role in the incidence of atherosclerosis and coronary heart diseases (CHD).
2. Substance P-mediated chemokine production promotes monocyte migration.
作者: Sergei Spitsin.;John Meshki.;Angela Winters.;Florin Tuluc.;Tami D Benton.;Steven D Douglas.
来源: J Leukoc Biol. 2017年101卷4期967-973页
The neuropeptide SP has physiologic and pathophysiologic roles in CNS and peripheral tissues and is involved in crosstalk between nervous and immune systems in various conditions, including HIV and SIV infection. Increased SP levels were demonstrated in plasma of HIV+ individuals as well as in the CNS of SIV-infected, nonhuman primates. SP increases HIV infection in macrophages through interaction with its receptor, NK1R. The SP effect on immune system is both pro- and anti-inflammatory and includes up-regulation of a number of cytokines and cell receptors. The main goal of this study was to determine whether there is interplay between monocyte exposure to SP and recruitment into sites of inflammation. We now demonstrate that exposure of either human macrophages or PBMCs to SP leads to increased production of chemokines, including MCP-1, for which expression is limited to cells of the myeloid lineage. This effect is inhibited by the NK1R antagonist, aprepitant. Exposure to conditioned medium derived from SP-treated PBMCs resulted in increased monocyte migration through semipermeable membranes and an in vitro human BBB model. Monocyte migration was blocked by anti-MCP-1 antibodies. Our results suggest that increased SP levels associated with HIV and other inflammatory conditions may contribute to increased monocyte migration into the CNS and other tissues through a MCP-1-dependent mechanism.
3. Methionine-mediated gene expression and characterization of the CmhR regulon in Streptococcus pneumoniae.
This study investigated the transcriptomic response of Streptococcus pneumoniae D39 to methionine. Transcriptome comparison of the S. pneumoniae D39 wild-type grown in chemically defined medium with 0-10 mM methionine revealed the elevated expression of various genes/operons involved in methionine synthesis and transport (fhs, folD, gshT, metA, metB-csd, metEF, metQ, tcyB, spd-0150, spd-0431 and spd-0618). Furthermore, β-galactosidase assays and quantitative RT-PCR studies demonstrated that the transcriptional regulator, CmhR (SPD-0588), acts as a transcriptional activator of the fhs, folD, metB-csd, metEF, metQ and spd-0431 genes. A putative regulatory site of CmhR was identified in the promoter region of CmhR-regulated genes and this CmhR site was further confirmed by promoter mutational experiments.
4. miR-205 mediates the inhibition of cervical cancer cell proliferation using olmesartan.
作者: Zhang Yue.;Zhang Yun-Shan.;Xue Feng-Xia.
来源: J Renin Angiotensin Aldosterone Syst. 2016年17卷3期1470320316663327页
The renin-angiotensin-aldosterone system has become known as a prerequisite for tumor angiogenesis that is now recognized as a crucial step in the development of tumors, including cervical cancer. The Ang II-AT1R pathway is known to play an important role in tumor angiogenesis. MicroRNAs (miRNAs) are a class of small, regulating RNAs that participate in tumor genesis, differentiation and proliferation. The current study focused on the anti-tumor mechanism of olmesartan, a novel angiotensin II antagonist, on cervical cancer cells.
5. Electromechanical Conditioning of Adult Progenitor Cells Improves Recovery of Cardiac Function After Myocardial Infarction.
作者: Aida Llucià-Valldeperas.;Carolina Soler-Botija.;Carolina Gálvez-Montón.;Santiago Roura.;Cristina Prat-Vidal.;Isaac Perea-Gil.;Benjamin Sanchez.;Ramon Bragos.;Gordana Vunjak-Novakovic.;Antoni Bayes-Genis.
来源: Stem Cells Transl Med. 2017年6卷3期970-981页
Cardiac cells are subjected to mechanical and electrical forces, which regulate gene expression and cellular function. Therefore, in vitro electromechanical stimuli could benefit further integration of therapeutic cells into the myocardium. Our goals were (a) to study the viability of a tissue-engineered construct with cardiac adipose tissue-derived progenitor cells (cardiac ATDPCs) and (b) to examine the effect of electromechanically stimulated cardiac ATDPCs within a myocardial infarction (MI) model in mice for the first time. Cardiac ATDPCs were electromechanically stimulated at 2-millisecond pulses of 50 mV/cm at 1 Hz and 10% stretching during 7 days. The cells were harvested, labeled, embedded in a fibrin hydrogel, and implanted over the infarcted area of the murine heart. A total of 39 animals were randomly distributed and sacrificed at 21 days: groups of grafts without cells and with stimulated or nonstimulated cells. Echocardiography and gene and protein analyses were also carried out. Physiologically stimulated ATDPCs showed increased expression of cardiac transcription factors, structural genes, and calcium handling genes. At 21 days after implantation, cardiac function (measured as left ventricle ejection fraction between presacrifice and post-MI) increased up to 12% in stimulated grafts relative to nontreated animals. Vascularization and integration with the host blood supply of grafts with stimulated cells resulted in increased vessel density in the infarct border region. Trained cells within the implanted fibrin patch expressed main cardiac markers and migrated into the underlying ischemic myocardium. To conclude, synchronous electromechanical cell conditioning before delivery may be a preferred alternative when considering strategies for heart repair after myocardial infarction. Stem Cells Translational Medicine 2017;6:970-981.
6. β-Elemene Selectively Inhibits the Proliferation of Glioma Stem-Like Cells Through the Downregulation of Notch1.
作者: Hai-Bin Feng.;Jing Wang.;Hao-Ran Jiang.;Xin Mei.;Yi-Ying Zhao.;Fu-Rong Chen.;Yue Qu.;Ke Sai.;Cheng-Cheng Guo.;Qun-Ying Yang.;Zong-Ping Zhang.;Zhong-Ping Chen.
来源: Stem Cells Transl Med. 2017年6卷3期830-839页
Glioma is the most frequent primary central nervous system tumor. Although the current first-line medicine, temozolomide (TMZ), promotes patient survival, drug resistance develops easily. Thus, it is important to investigate novel therapeutic reagents to solidify the treatment effect. β-Elemene (bELE) is a compound from a Chinese herb whose anticancer effect has been shown in various types of cancer. However, its role in the inhibition of glioma stem-like cells (GSLCs) has not yet been reported. We studied both the in vitro and the in vivo inhibitory effect of bELE and TMZ in GSLCs and parental cells and their combined effects. The molecular mechanisms were also investigated. We also optimized the delivery methods of bELE. We found that bELE selectively inhibits the proliferation and sphere formation of GSLCs, other than parental glioma cells, and TMZ exerts its effects on parental cells instead of GSLCs. The in vivo data confirmed that the combination of bELE and TMZ worked better in the xenografts of GSLCs, mimicking the situation of tumorigenesis of human cancer. Notch1 was downregulated with bELE treatment. Our data also demonstrated that the continuous administration of bELE produces an ideal effect to control tumor progression. Our findings have demonstrated, for the first time, that bELE could compensate for TMZ to kill both GSLCs and nonstem-like cancer cells, probably improving the prognosis of glioma patients tremendously. Notch1 might be a downstream target of bELE. Therefore, our data shed light on improving the outcomes of glioma patients by combining bELE and TMZ. Stem Cells Translational Medicine 2017;6:830-839.
7. Astragaloside IV Enhances Cisplatin Chemosensitivity in Human Colorectal Cancer via Regulating NOTCH3.
Although astragaloside IV exhibits anti-inflammation, immunoregulatory, and anticancer properties, the chemosensitization effects of astragaloside IV in colorectal cancer have never been reported. Our study tested whether astragaloside could increase cisplatin sensitivity in colorectal cancer. CCK-8 assay was used to measure the cell viability of colorectal cancer cells. Quantitative real-time PCR and Western blot were performed to determine the mRNA and protein expression, respectively. Our data revealed that astragaloside IV administration significantly suppressed the cell growth of colorectal cancer cells, whereas no obvious cytotoxicity of astragaloside IV was observed in nonmalignant colonic cells. In addition, combined treatment with astragaloside IV dramatically elevated the chemosensitivity of colorectal cancer cells to cisplatin. Mechanical investigation revealed that the mRNA and protein expression of NOTCH3 was significantly lower in cisplatin and astragaloside IV-treated cells compared with cells treated with cisplatin alone. On the contrary, no obvious changes in tumor cell growth were shown after upregulation of NOTCH3 whether in the presence or absence of astragaloside IV. Thus, our data demonstrate that astragaloside IV increases the chemosensitivity of colorectal cancer cells to cisplatin, at least partly, through inhibition of NOTCH3. This study suggests that combined therapy with astragaloside IV might be a novel therapeutic approach for colorectal cancer.
8. The role of exercise training and the endocannabinoid system in atherosclerotic plaque burden and composition in Apo-E-deficient mice.
作者: Michalis Katsimpoulas.;Nikolaos E Kadoglou.;Petros Moustardas.;Alkistis Kapelouzou.;Eleni Dede.;Nikolaos Kostomitsopoulos.;Panayotis E Karayannacos.;Alkiviadis Kostakis.;Christos D Liapis.
来源: Hellenic J Cardiol. 2016年57卷6期417-425页
We investigated the effect of combining exercise training and treatment with an endocannabinoid receptor 1 inhibitor (Rimonabant) on atherosclerosis burden and composition.
9. B-cells with a FasL expressing regulatory phenotype are induced following successful anti-tuberculosis treatment.
作者: Ilana C van Rensburg.;Léanie Kleynhans.;Alana Keyser.;Gerhard Walzl.;Andre G Loxton.
来源: Immun Inflamm Dis. 2017年5卷1期57-67页
Studies show that B-cells, in addition to producing antibodies and antigen-presentation, are able to produce cytokines as well. These include regulatory cytokines such as IL-10 by regulatory B-cells. Furthermore, a rare regulatory subset of B-cells have the potential to express FasL, which is a death-inducing ligand. This subset of B-cells have a positive role during autoimmune disease, but has not yet been studied during tuberculosis. These FasL-expressing B-cells are induced by bacterial LPS and CpG, thus we hypothesized that this phenotype might be induced during tuberculosis as well.
10. [Research progress on the effect of glucocorticoid receptor signaling pathways in bladder cancer].
作者: Sheng Feng.;Jijun Chen.;Yichun Zheng.
来源: Zhejiang Da Xue Xue Bao Yi Xue Ban. 2016年45卷6期655-660页
Glucocorticoid receptor (GR) is identified as a member of nuclear receptor family. To exert its biological action, the ligand bound GR is translocated from the cytoplasm into the nucleus by regulating transcriptional signals of related genes. In clinical practice, the effects of glucocorticoid are often mediated by GR signaling pathways. An increasing number of studies have indicated that GR signaling pathways play an essential role in the proliferation, invasion and prognosis of bladder cancer. Meanwhile, the new-generation selective GR activator improves its anti-tumor effects, and at the same time reduces the adverse reactions of hormones, which probably raises the prospect for the treatment of bladder cancer.
11. [High glucose dialysate enhances peritoneal fibrosis through upregulating glucose transporters GLUT1 and SGLT1].
作者: Mengqi Hong.;Zhenyu Nie.;Zhengyue Chen.;Xiongwei Yu.;Beiyan Bao.
来源: Zhejiang Da Xue Xue Bao Yi Xue Ban. 2016年45卷6期598-606页
Objective: To investigate the role of glucose transporter 1 (GLUT1) and sodium-glucose cotransporter 1 (SGLT1) in high glucose dialysate-induced peritoneal fibrosis. Methods: Thirty six male SD rats were randomly divided into 6 groups (6 in each):normal control group, sham operation group, peritoneal dialysis group (PD group), PD+phloretin group (PD+T group), PD+phlorizin group (PD+Z group), PD+phloretin+phlorizin group (PD+T+Z group). Rat model of uraemia was established using 5/6 nephrotomy, and 2.5% dextrose peritoneal dialysis solution was used in peritoneal dialysis. Peritoneal equilibration test was performed 24 h after dialysis to evaluate transport function of peritoneum in rats; HE staining was used to observe the morphology of peritoneal tissue; and immunohistochemistry was used to detect the expression of GLUT1, SGLT1, TGF-β1 and connective tissue growth factor (CTGF) in peritoneum. Human peritoneal microvascular endothelial cells (HPECs) were divided into 5 groups:normal control group, peritoneal dialysis group (PD group), PD+phloretin group (PD+T group), PD+phlorezin group (PD+Z group), and PD+phloretin+phlorezin group (PD+T+Z group). Real time PCR and Western blotting were used to detect mRNA and protein expressions of GLUT1, SGLT1, TGF-β1, CTGF in peritoneal membrane and HPECs. Results:In vivo, compared with sham operation group, rats in PD group had thickened peritoneum, higher ultrafiltration volume, and the mRNA and protein expressions of GLUT1, SGLT1, CTGF, TGF-β1 were significantly increased (all P<0.05); compared with PD group, thickened peritoneum was attenuated, and the mRNA and protein expressions of GLUT1, SGLT1, CTGF, TGF-β1 were significantly decreased in PD+T, PD+Z and PD+T+Z groups (all P<0.05). Pearson's correlation analysis showed that the expressions of GLUT1, SGLT1 in peritoneum were positively correlated with the expressions of TGF-β1 and CTGF (all P<0.05). In vitro, the mRNA and protein expressions of GLUT1, SGLT1, TGF-β1, CTGF were significantly increased in HPECs of peritoneal dialysis group (all P<0.05), and those in PD+T, PD+Z, and PD+T+Z groups were decreased (all P<0.05). Pearson's correlation analysis showed that the expressions of GLUT1, SGLT1 in HPECs were positively correlated with the expressions of TGF-β1 and CTGF (all P<0.05). Conclusion: High glucose peritoneal dialysis fluid may promote peritoneal fibrosis by upregulating the expressions of GLUT1 and SGLT1.
12. [Effect of miR-705 on osteogenic differentiation of mouse embryo osteoblast precursor cells MC3T3-E1].
作者: Xiaohong Yang.;Kun Yang.;Li Liao.;Yan Jin.
来源: Zhejiang Da Xue Xue Bao Yi Xue Ban. 2016年45卷6期575-580页
Objective: To investigate the effect of miR-705 on osteogenic differentiation of mouse embryo osteoblast precursor (MC3T3-E1) cells. Methods: miR-705 mimics, inhibitors and negative control were transfected into MC3T3-E1 cells. Alkaline phosphates (ALP) staining were performed and quantified after 7 days of osteogenic medium induction. The mRNA and protein expression levels of runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) were detected by real-time RT-PCR and Western blot after 14 days of osteogenic induction. Alizarin red staining was performed and quantified in MC3T3-E1 cells after 21 days of osteogenic induction. Results: After 7 days of osteogenic induction, ALP staining showed that overexpression of miR-705 significantly reduced ALP activity, whereas knockdown of miR-705 increased ALP activity (all P<0.05). Consistently, after 14 days of osteogenic induction, mRNA and protein expressions of Runx2 and OCN were suppressed by overexpression of miR-705, whereas they were promoted by knockdown of miR-705 (all P<0.05). After 21 days of osteogenic induction, alizarin red staining showed that overexpression of miR-705 significantly reduced the formation of mineralized node, the opposite results were found in miR-705 knockdown group (all P<0.05). Conclusion: miR-705 can inhibit the osteogenic differentiation of MC3T3-E1 cells.
13. PEP-1-GRX-1 Modulates Matrix Metalloproteinase-13 and Nitric Oxide Expression of Human Articular Chondrocytes.
作者: Hyun Sook Hwang.;In Young Park.;Hyun Ah Kim.;Soo Young Choi.
来源: Cell Physiol Biochem. 2017年41卷1期252-264页
The protein transduction domain (PTD) enables therapeutic proteins to directly penetrate the membranes of cells and tissues, and has been increasingly utilized. Glutaredoxin-1 (GRX-1) is an endogenous antioxidant enzyme involved in the cellular redox homeostasis system. In this study, we investigated whether PEP-1-GRX-1, a fusion protein of GRX-1 and PEP-1 peptide, a PTD, could suppress catabolic responses in primary human articular chondrocytes and a mouse carrageenan-induced paw edema model.
14. Anxiety and Hyperlocomotion Induced by Chronic Unpredictable Mild Stress Can Be Moderated with Melatonin Treatment.
Preclinical studies have shown that melatonin exercised antidepressant-like and anxiolyticlike effects in animal models of anxiety. The aim of the present study was to correlate the changes in behaviour induced by melatonin treatment with the activity of the dopaminergic system in the hippocampus of Wistar rats exposed to chronic, unpredictable, mild stress (CUMS). Male Wistar rats, 11 weeks old, were subjected to chronic stress for 28 successive days. Separate groups of control and stressed rats were intraperitoneally injected daily either with melatonin (10 mg/kg/day, i.p.) or placebo (5% ethanol). The open-field and elevated plus-maze tests were used to assess locomotor activities and anxiety levels. The content of dopamine (DA) in the hippocampal tissues was determined using radioenzymatic assay, while changes in tyrosine hydroxylase (TH) mRNA and protein levels in the hippocampus were determined using real-time RT-PCR and Western immunoblotting. Chronic stress led to reduction in the hippocampal dopaminergic content without affecting the levels of TH protein. These changes were accompanied by increased locomotor activity and higher anxiety levels in the open-field test. Administration of melatonin for 28 days resulted in an increase in the hippocampal DA content as a result of elevated TH protein levels. Melatonin showed an improvement in anxiety-like behaviour along with significantly reduced exploration. We could conclude that melatonin may stimulate dopaminergic synthesis in the hippocampus in order to suppress stress-induced behaviour.
15. A high-throughput small molecule screen identifies synergism between DNA methylation and Aurora kinase pathways for X reactivation.
作者: Derek Lessing.;Thomas O Dial.;Chunyao Wei.;Bernhard Payer.;Lieselot L G Carrette.;Barry Kesner.;Attila Szanto.;Ajit Jadhav.;David J Maloney.;Anton Simeonov.;Jimmy Theriault.;Thomas Hasaka.;Antonio Bedalov.;Marisa S Bartolomei.;Jeannie T Lee.
来源: Proc Natl Acad Sci U S A. 2016年113卷50期14366-14371页
X-chromosome inactivation is a mechanism of dosage compensation in which one of the two X chromosomes in female mammals is transcriptionally silenced. Once established, silencing of the inactive X (Xi) is robust and difficult to reverse pharmacologically. However, the Xi is a reservoir of >1,000 functional genes that could be potentially tapped to treat X-linked disease. To identify compounds that could reactivate the Xi, here we screened ∼367,000 small molecules in an automated high-content screen using an Xi-linked GFP reporter in mouse fibroblasts. Given the robust nature of silencing, we sensitized the screen by "priming" cells with the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5azadC). Compounds that elicited GFP activity include VX680, MLN8237, and 5azadC, which are known to target the Aurora kinase and DNA methylation pathways. We demonstrate that the combinations of VX680 and 5azadC, as well as MLN8237 and 5azadC, synergistically up-regulate genes on the Xi. Thus, our work identifies a synergism between the DNA methylation and Aurora kinase pathways as being one of interest for possible pharmacological reactivation of the Xi.
16. Apoptosis of rat hepatic stellate cells induced by diallyl trisulfide and proteomics profiling in vitro.
作者: Yajie Zhang.;Xiaoming Zhou.;Lipeng Xu.;Lulu Wang.;Jinling Liu.;Jing Ye.;Pengxin Qiu.;Qinghua Liu.
来源: Can J Physiol Pharmacol. 2017年95卷5期463-473页
Diallyl trisulfide (DATS), a major garlic derivative, inhibits cell proliferation and triggers apoptosis in a variety of cancer cell lines. However, the effects of DATS on hepatic stellate cells (HSCs) remain unknown. The aim of this study was to analyze the effects of DATS on cell proliferation and apoptosis, as well as the protein expression profile in rat HSCs. Rat HSCs were treated with or without 12 and 24 μg/mL DATS for various time intervals. Cell proliferation and apoptosis were determined using tetrazolium dye (MTT) colorimetric assay, bromodeoxyuridine (5-bromo-2'-deoxyuridine; BrdU) assay, Hoechst 33342 staining, electroscopy, and flow cytometry. Protein expression patterns in HSCs were systematically studied using 2-dimensional electrophoresis and mass spectrometry. DATS inhibited cell proliferation and induced apoptosis of HSCs in a time-dependent manner. We observed clear morphological changes in apoptotic HSCs and dramatically increased annexin V-positive - propidium iodide negative apoptosis compared with the untreated control group. Twenty-one significant differentially expressed proteins, including 9 downregulated proteins and 12 upregulated proteins, were identified after DATS administration, and most of them were involved in apoptosis. Our results suggest that DATS is an inducer of apoptosis in HSCs, and several key proteins may be involved in the molecular mechanism of apoptosis induced by DATS.
17. Human Adipose-Derived Stem Cells Expanded Under Ambient Oxygen Concentration Accumulate Oxidative DNA Lesions and Experience Procarcinogenic DNA Replication Stress.
作者: Rémy Bétous.;Marie-Laure Renoud.;Claire Hoede.;Ignacio Gonzalez.;Natalie Jones.;Michel Longy.;Luc Sensebé.;Christophe Cazaux.;Jean-Sébastien Hoffmann.
来源: Stem Cells Transl Med. 2017年6卷1期68-76页
Adipose-derived stem cells (ADSCs) have led to growing interest in cell-based therapy because they can be easily harvested from an abundant tissue. ADSCs must be expanded in vitro before transplantation. This essential step causes concerns about the safety of adult stem cells in terms of potential transformation. Tumorigenesis is driven in its earliest step by DNA replication stress, which is characterized by the accumulation of stalled DNA replication forks and activation of the DNA damage response. Thus, to evaluate the safety of ADSCs during ex vivo expansion, we monitored DNA replication under atmospheric (21%) or physiologic (1%) oxygen concentration. Here, by combining immunofluorescence and DNA combing, we show that ADSCs cultured under 21% oxygen accumulate endogenous oxidative DNA lesions, which interfere with DNA replication by increasing fork stalling events, thereby leading to incomplete DNA replication and fork collapse. Moreover, we found by RNA sequencing (RNA-seq) that culture of ADSCs under atmospheric oxygen concentration leads to misexpression of cell cycle and DNA replication genes, which could contribute to DNA replication stress. Finally, analysis of acquired small nucleotide polymorphism shows that expansion of ADSCs under 21% oxygen induces a mutational bias toward deleterious transversions. Overall, our results suggest that expanding ADSCs at a low oxygen concentration could reduce the risk for DNA replication stress-associated transformation, as occurs in neoplastic tissues. Stem Cells Translational Medicine 2017;6:68-76.
18. Regeneration of Articular Cartilage by Human ESC-Derived Mesenchymal Progenitors Treated Sequentially with BMP-2 and Wnt5a.
作者: Jason D Gibson.;Michael B O'Sullivan.;Farhang Alaee.;David N Paglia.;Ryu Yoshida.;Rosa M Guzzo.;Hicham Drissi.
来源: Stem Cells Transl Med. 2017年6卷1期40-50页
The success of cell-based therapies to restore joint cartilage requires an optimal source of reparative progenitor cells and tight control of their differentiation into a permanent cartilage phenotype. Bone morphogenetic protein 2 (BMP-2) has been extensively shown to promote mesenchymal cell differentiation into chondrocytes in vitro and in vivo. Conversely, developmental studies have demonstrated decreased chondrocyte maturation by Wingless-Type MMTV Integration Site Family, Member 5A (Wnt5a). Thus, we hypothesized that treatment of human embryonic stem cell (hESC)-derived chondroprogenitors with BMP-2 followed by Wnt5a may control the maturational progression of these cells into a hyaline-like chondrocyte phenotype. We examined the effects of sustained exposure of hESC-derived mesenchymal-like progenitors to recombinant Wnt5a or BMP-2 in vitro. Our data indicate that BMP-2 promoted a strong chondrogenic response leading to terminal maturation, whereas recombinant Wnt5a induced a mild chondrogenic response without promoting hypertrophy. Moreover, Wnt5a suppressed BMP-2-mediated chondrocyte maturation, preventing the formation of fibrocartilaginous tissue in high-density cultures treated sequentially with BMP-2 and Wnt5a. Implantation of scaffoldless pellets of hESC-derived chondroprogenitors pretreated with BMP-2 followed by Wnt5a into rat chondral defects induced an articular-like phenotype in vivo. Together, the data establish a novel role for Wnt5a in controlling the progression from multipotency into an articular-like cartilage phenotype in vitro and in vivo. Stem Cells Translational Medicine 2017;6:40-50.
19. Membrane-bound versus soluble major histocompatibility complex Class I-related chain A and major histocompatibility complex Class I-related chain B differential expression: Mechanisms of tumor eradication versus evasion and current drug development strategies.
Major histocompatibility complex Class I-related chain A/chain B (MICA/MICB) is stress-inducible, highly polymorphic ligands whose expression at the transcript level has been detected in all tissues except the central nervous system. However, their restricted protein expression is due to their regulation at the posttranslational level. Its levels are elevated in virally infected and neoplastically transformed cells. Membrane expression of this NKG2DL marks the aberrant cells for elimination by those immune effector cells that express the cognate NKG2D receptor. Among the evasion strategies developed by tumors, the metalloprotease-dependent shedding of MICA/MICB from tumors (either the free or the exosome form) can contribute to the inhibition of cytolysis by the immune effector cells (all NK cells, most NKT cells; γδ CD8+ T cells and αβ CD8+ T cells, as well as some αβ CD4+ T cells). There are micro-RNA clusters that regulate surface expression and shedding. Polymorphic variants can be used as susceptibility/associative markers and can also possibly be used to correlate with tumor survival as well as staging/grading of tumors. Variations in the expression level require quantification of this marker for diagnostic/prognostic and therapeutic purposes. Mechanism-based studies would provide a better tumor-specific understanding of their relative roles in the processes of tumor cell elimination versus growth and progression. Last but not least, conventional, interlaboratory validated assays (for, e.g., antibody-based methods) should be replaced by robust, reproducible, feasible biophysics-based methods using tumor biopsies. Further, correlative DNA polymorphism-based studies can be done using biological fluids (for, e.g., human saliva) that can be sampled by minimally invasive means.
20. Accumulation and tolerance to cadmium heavy metal ions and induction of 14-3-3 gene expression in response to cadmium exposure in Coprinus atramentarius.
作者: Chengjian Xie.;Liujie Hu.;Yongzhu Yang.;Dunxiu Liao.;Xingyong Yang.
来源: Microbiol Res. 2017年196卷1-6页
Cadmium (Cd), one of the most toxic heavy-metal pollutants, has a strong and irreversible tendency to accumulate. Bioremediation is a promising technology to remedy and control heavy metal pollutants because of its low cost and ability to recycle heavy metals. Coprinus atramentarius is recognized as being able to accumulate heavy metal ions. In this work, C. atramentarius is cultivated on a solid medium containing Cd2+ ions to analyze its ability to tolerate different concentrations of the heavy metal ion. It is found that the growth of C. atramentarius is not significantly inhibited when the concentration of Cd2+ is less than 0.6mgL-1. The accumulation capacity of C. atramentarius at different Cd2+ concentrations also was determined. The results show that 76% of the Cd2+ present can be accumulated even when the concentration of the Cd2+ is 1mgL-1. The different proteins of C. atramentarius exposed to Cd2+ were further analyzed using gel electrophoresis. A 14-3-3 protein was identified and shown to be significantly up-regulated. In a further study, a full-length 14-3-3 gene was cloned containing a 759bp open reading frame encoding a polypeptide consisting of 252 amino acids and 3 introns. The gene expression work also showed that the 14-3-3 was significantly induced, and showed coordinated patterns of expression, with Cd2+ exposure.
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