Bassa LM et al. (JAN 2016)
Phytomedicine : international journal of phytotherapy and phytopharmacology 23 1 87--94
Rhodiola crenulata induces an early estrogenic response and reduces proliferation and tumorsphere formation over time in MCF7 breast cancer cells.
BACKGROUND Rhodiola crenulata is a Tibetan mountainous plant,commonly used in Eastern alternative medicine. Many phytochemicals possess estrogenic activity,a critical regulator of proliferation in mammary epithelial cells. We have previously characterized anti-cancer properties of R. crenulata in aggressive triple negative breast cancer cells,lacking the expression of estrogen receptor. Currently,it is unknown whether R. crenulata exerts estrogenic effects and as such consumption may be a concern for women with estrogen receptor positive breast cancer that use Rhodiola sp. to relieve mild to moderate depression. PURPOSE In this study,we wished to determine whether a hydroalcoholic fraction of the R. crenulata root extract exhibits estrogenic activity in estrogen receptor positive (ER+) breast cancer cells in vitro and whether it affects normal mammary epithelial ER target gene expression in vivo. METHODS ER transcriptional activity was analyzed in MCF7 cells expressing an ERE reporter construct and confirmed via qPCR of endogenous ER target genes. We also monitored cellular proliferation over time. Additionally,to assess stem-like properties in MCF7 cells,we performed a tumorsphere formation assay under anchorage independent conditions. We examined whether R. crenulata treatment reduced $$-catenin levels via Western blotting and measured $$-catenin transcriptional activity by a reporter assay. To examine the effects of R. crenulata on normal mammary epithelial cells,we performed immunohistochemical staining of ER and PR in the mammary glands of mice fed R. crenulata for 12 weeks. RESULTS We show an initial activation of ER transcriptional activity by dual reporter assay,qPCR and proliferation of MCF7 ER+ cells in response to 24 h of R. crenulata treatment. However,upon longer treatment basal and R. crenulata induced transcriptional activity was suppressed. There was a decrease in cell doubling times and a decrease in tumorsphere formation. In association with these changes,ER$$ transcript levels were decreased and active $$-catenin levels were reduced in the cells treated for 2 weeks. Finally,we show no change in estrogen targets in normal mammary cells in vivo. CONCLUSION These data suggest that the R. crenulata extract contains components with estrogenic activity. However,R. crenulata treatment could still be protective in ER+ breast cancer cells,as longer treatment reduced the transcriptional activity of $$-catenin and ER responses leading to reduced proliferation and tumorsphere formation. Furthermore,administration of 20 mg/kg/day R. crenulata to mice did not have an observable effect on mammary epithelial ER$$ target gene expression in vivo.
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产品类型：
产品号#：
05620
产品名：
MammoCult™ 人源培养基套装
文献
Wolfrum K et al. (JAN 2010)
PLoS ONE 5 10 e13703
The LARGE principle of cellular reprogramming: lost, acquired and retained gene expression in foreskin and amniotic fluid-derived human iPS cells.
Human amniotic fluid cells (AFCs) are routinely obtained for prenatal diagnostics procedures. Recently,it has been illustrated that these cells may also serve as a valuable model system to study developmental processes and for application in regenerative therapies. Cellular reprogramming is a means of assigning greater value to primary AFCs by inducing self-renewal and pluripotency and,thus,bypassing senescence. Here,we report the generation and characterization of human amniotic fluid-derived induced pluripotent stem cells (AFiPSCs) and demonstrate their ability to differentiate into the trophoblast lineage after stimulation with BMP2/BMP4. We further carried out comparative transcriptome analyses of primary human AFCs,AFiPSCs,fibroblast-derived iPSCs (FiPSCs) and embryonic stem cells (ESCs). This revealed that the expression of key senescence-associated genes are down-regulated upon the induction of pluripotency in primary AFCs (AFiPSCs). By defining distinct and overlapping gene expression patterns and deriving the LARGE (Lost,Acquired and Retained Gene Expression) Principle of Cellular Reprogramming,we could further highlight that AFiPSCs,FiPSCs and ESCs share a core self-renewal gene regulatory network driven by OCT4,SOX2 and NANOG. Nevertheless,these cell types are marked by distinct gene expression signatures. For example,expression of the transcription factors,SIX6,EGR2,PKNOX2,HOXD4,HOXD10,DLX5 and RAXL1,known to regulate developmental processes,are retained in AFiPSCs and FiPSCs. Surprisingly,expression of the self-renewal-associated gene PRDM14 or the developmental processes-regulating genes WNT3A and GSC are restricted to ESCs. Implications of this,with respect to the stability of the undifferentiated state and long-term differentiation potential of iPSCs,warrant further studies.
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产品类型：
产品号#：
85850
85857
产品名：
mTeSR™1
mTeSR™1
文献
Jaramillo M and Banerjee I (MAR 2012)
Journal of visualized experiments : JoVE 61 2--7
Endothelial cell co-culture mediates maturation of human embryonic stem cell to pancreatic insulin producing cells in a directed differentiation approach.
Embryonic stem cells (ESC) have two main characteristics: they can be indefinitely propagated in vitro in an undifferentiated state and they are pluripotent,thus having the potential to differentiate into multiple lineages. Such properties make ESCs extremely attractive for cell based therapy and regenerative treatment applications. However for its full potential to be realized the cells have to be differentiated into mature and functional phenotypes,which is a daunting task. A promising approach in inducing cellular differentiation is to closely mimic the path of organogenesis in the in vitro setting. Pancreatic development is known to occur in specific stages,starting with endoderm,which can develop into several organs,including liver and pancreas. Endoderm induction can be achieved by modulation of the nodal pathway through addition of Activin A in combination with several growth factors. Definitive endoderm cells then undergo pancreatic commitment by inhibition of sonic hedgehog inhibition,which can be achieved in vitro by addition of cyclopamine. Pancreatic maturation is mediated by several parallel events including inhibition of notch signaling; aggregation of pancreatic progenitors into 3-dimentional clusters; induction of vascularization; to name a few. By far the most successful in vitro maturation of ESC derived pancreatic progenitor cells have been achieved through inhibition of notch signaling by DAPT supplementation. Although successful,this results in low yield of the mature phenotype with reduced functionality. A less studied area is the effect of endothelial cell signaling in pancreatic maturation,which is increasingly being appreciated as an important contributing factor in in-vivo pancreatic islet maturation. The current study explores such effect of endothelial cell signaling in maturation of human ESC derived pancreatic progenitor cells into insulin producing islet-like cells. We report a multi-stage directed differentiation protocol where the human ESCs are first induced towards endoderm by Activin A along with inhibition of PI3K pathway. Pancreatic specification of endoderm cells is achieved by inhibition of sonic hedgehog signaling by Cyclopamine along with retinoid induction by addition of Retinoic Acid. The final stage of maturation is induced by endothelial cell signaling achieved by a co-culture configuration. While several endothelial cells have been tested in the co-culture,herein we present our data with rat heart microvascular endothelial Cells (RHMVEC),primarily for the ease of analysis.
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产品类型：
产品号#：
85850
85857
产品名：
mTeSR™1
mTeSR™1
文献
Prabhu VV et al. (APR 2016)
Cancer research 76 7 1989--1999
Small-Molecule Prodigiosin Restores p53 Tumor Suppressor Activity in Chemoresistant Colorectal Cancer Stem Cells via c-Jun-Mediated $$Np73 Inhibition and p73 Activation.
Tumor suppressor p53 is frequently mutated or inactivated in colorectal cancer. In contrast,p53 family member p73 is rarely mutated in colorectal cancer and p73 activation elicits p53-like tumor suppression. Colorectal cancer stem cells (CRCSC) comprise a rare self-renewing subpopulation that contributes to tumor maintenance and chemoresistance. p53 restoration is known to target CRCSCs,but p73 restoration in CRCSCs has not been examined. In this study,we investigated the effects of the small-molecule prodigiosin,which restores the p53 pathway in tumor cells via p73 activation,on CRCSCs in vitro and in vivo Prodigiosin prevented colonosphere formation independent of p53 status and reduced the viability of self-renewing,5-fluorouracil-resistant Aldefluor positive [Aldefluor(+)] CRCSCs in vitro Furthermore,prodigiosin inhibited the growth of xenograft tumors initiated with Aldefluor+ cells without toxic effects and limited the tumorigenic potential of these cells. Consistently,prodigiosin induced activation of a p53-responsive luciferase reporter in colonospheres,Aldefluor(+) cells,and tumor xenografts. Mechanistic studies revealed that prodigiosin increased the levels of p73 and reduced levels of the oncogenic N-terminally truncated isoform $$Np73 in Aldefluor(+) cells. Accordingly,p73 knockdown or $$Np73 overexpression suppressed prodigiosin-mediated inhibition of colonosphere formation. Moreover,prodigiosin increased levels of the transcription factor c-Jun,a regulator of p73 and $$Np73,in both the cytoplasm and nucleus. c-Jun knockdown attenuated prodigiosin-mediated p53-reporter activation,$$Np73 downregulation,p73 activation,and cell death. Collectively,our findings highlight the previously uncharacterized use of p73-activating therapeutics to target CRCSCs. Cancer Res; 76(7); 1989-99. textcopyright2016 AACR.
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Vukovic J et al. (APR 2013)
Journal of Neuroscience 33 15 6603--6613
Immature Doublecortin-Positive Hippocampal Neurons Are Important for Learning But Not for Remembering
It is now widely accepted that hippocampal neurogenesis underpins critical cognitive functions,such as learning and memory. To assess the behavioral importance of adult-born neurons,we developed a novel knock-in mouse model that allowed us to specifically and reversibly ablate hippocampal neurons at an immature stage. In these mice,the diphtheria toxin receptor (DTR) is expressed under control of the doublecortin (DCX) promoter,which allows for specific ablation of immature DCX-expressing neurons after administration of diphtheria toxin while leaving the neural precursor pool intact. Using a spatially challenging behavioral test (a modified version of the active place avoidance test),we present direct evidence that immature DCX-expressing neurons are required for successful acquisition of spatial learning,as well as reversal learning,but are not necessary for the retrieval of stored long-term memories. Importantly,the observed learning deficits were rescued as newly generated immature neurons repopulated the granule cell layer upon termination of the toxin treatment. Repeat (or cyclic) depletion of immature neurons reinstated behavioral deficits if the mice were challenged with a novel task. Together,these findings highlight the potential of stimulating neurogenesis as a means to enhance learning.
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产品类型：
产品号#：
05700
05701
05702
产品名：
NeuroCult™ 基础培养基（小鼠和大鼠）
NeuroCult™ 扩增添加物（小鼠和大鼠）
NeuroCult™扩增试剂盒（小鼠和大鼠）
文献
Stadtfeld M et al. (MAR 2008)
Cell stem cell 2 3 230--40
Defining molecular cornerstones during fibroblast to iPS cell reprogramming in mouse.
Ectopic expression of the transcription factors Oct4,Sox2,c-Myc,and Klf4 in fibroblasts generates induced pluripotent stem (iPS) cells. Little is known about the nature and sequence of molecular events accompanying nuclear reprogramming. Using doxycycline-inducible vectors,we have shown that exogenous factors are required for about 10 days,after which cells enter a self-sustaining pluripotent state. We have identified markers that define cell populations prior to and during this transition period. While downregulation of Thy1 and subsequent upregulation of SSEA-1 occur at early time points,reactivation of endogenous Oct4,Sox2,telomerase,and the silent X chromosome mark late events in the reprogramming process. Cell sorting with these markers allows for a significant enrichment of cells with the potential to become iPS cells. Our results suggest that factor-induced reprogramming is a gradual process with defined intermediate cell populations that contain the majority of cells poised to become iPS cells.
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产品类型：
产品号#：
72742
产品名：
强力霉素(盐酸盐)
文献
Ingersoll MA et al. (JAN 2010)
Blood 115 3 e10--9
Comparison of gene expression profiles between human and mouse monocyte subsets.
Blood of both humans and mice contains 2 main monocyte subsets. Here,we investigated the extent of their similarity using a microarray approach. Approximately 270 genes in humans and 550 genes in mice were differentially expressed between subsets by 2-fold or more. More than 130 of these gene expression differences were conserved between mouse and human monocyte subsets. We confirmed numerous of these differences at the cell surface protein level. Despite overall conservation,some molecules were conversely expressed between the 2 species' subsets,including CD36,CD9,and TREM-1. Other differences included a prominent peroxisome proliferator-activated receptor gamma (PPARgamma) signature in mouse monocytes,which is absent in humans,and strikingly opposed patterns of receptors involved in uptake of apoptotic cells and other phagocytic cargo between human and mouse monocyte subsets. Thus,whereas human and mouse monocyte subsets are far more broadly conserved than currently recognized,important differences between the species deserve consideration when models of human disease are studied in mice.
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EasySep™小鼠TIL（CD45）正选试剂盒
文献
产品手册Small Molecules for Cancer Research
产品手册ELISA Kits for Immunology Research
产品手册STEMvision™ Automated and Standardized Counting of Mouse Bone Marrow CFU Assays
