Screen for chemical modulators of autophagy reveals novel therapeutic inhibitors of mTORC1 signaling.
BACKGROUND Mammalian target of rapamycin complex 1 (mTORC1) is a protein kinase that relays nutrient availability signals to control numerous cellular functions including autophagy,a process of cellular self-eating activated by nutrient depletion. Addressing the therapeutic potential of modulating mTORC1 signaling and autophagy in human disease requires active chemicals with pharmacologically desirable properties. METHODOLOGY/PRINCIPAL FINDINGS Using an automated cell-based assay,we screened a collection of {\textgreater}3,500 chemicals and identified three approved drugs (perhexiline,niclosamide,amiodarone) and one pharmacological reagent (rottlerin) capable of rapidly increasing autophagosome content. Biochemical assays showed that the four compounds stimulate autophagy and inhibit mTORC1 signaling in cells maintained in nutrient-rich conditions. The compounds did not inhibit mTORC2,which also contains mTOR as a catalytic subunit,suggesting that they do not inhibit mTOR catalytic activity but rather inhibit signaling to mTORC1. mTORC1 inhibition and autophagosome accumulation induced by perhexiline,niclosamide or rottlerin were rapidly reversed upon drug withdrawal whereas amiodarone inhibited mTORC1 essentially irreversibly. TSC2,a negative regulator of mTORC1,was required for inhibition of mTORC1 signaling by rottlerin but not for mTORC1 inhibition by perhexiline,niclosamide and amiodarone. Transient exposure of immortalized mouse embryo fibroblasts to these drugs was not toxic in nutrient-rich conditions but led to rapid cell death by apoptosis in starvation conditions,by a mechanism determined in large part by the tuberous sclerosis complex protein TSC2,an upstream regulator of mTORC1. By contrast,transient exposure to the mTORC1 inhibitor rapamycin caused essentially irreversible mTORC1 inhibition,sustained inhibition of cell growth and no selective cell killing in starvation. CONCLUSION/SIGNIFICANCE The observation that drugs already approved for human use can reversibly inhibit mTORC1 and stimulate autophagy should greatly facilitate the preclinical and clinical testing of mTORC1 inhibition for indications such as tuberous sclerosis,diabetes,cardiovascular disease and cancer.
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Jarrard JA et al. (DEC 1998)
Cancer research 58 23 5582--9
MUC1 is a novel marker for the type II pneumocyte lineage during lung carcinogenesis.
Abnormalities in mucin-type glycoprotein expression have been documented in a variety of cancers,identifying these molecules as targets for immunologically based therapies and prognostic/diagnostic assays. We examined the expression of the membrane-bound MUC1 mucin in normal,histologically atypical,and neoplastic lung to determine its potential contribution to lung carcinogenesis. In vivo,intense MUC1 immunoreactivity was present in normal type II pneumocytes as well as in a range of atypical lesions derived from type II cells and textgreater60% of primary and metastatic non-small cell lung cancers. Expression was not associated with altered survival,although it was highly correlated with the adenocarcinoma histology. A carcinogenesis model using 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone-exposed hamsters revealed that MUC1 mRNA increased prior to the histological appearance of tumors. In vitro studies using MUC1 expressing non-small cell lung cancer cell lines revealed that differentiation away from a type II cell lineage was associated with dramatic down-regulation of MUC1. We propose that MUC1 is a powerful new marker for the type II pneumocyte cell lineage that allows us to follow the type II pneumocyte lineage during the process of lung carcinogenesis.
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产品类型:
产品号#:
01423
产品名:
Iverson C et al. ( 2009)
Cancer research 69 17 6839--6847
RDEA119/BAY 869766: a potent, selective, allosteric inhibitor of MEK1/2 for the treatment of cancer.
The RAS-RAF-mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)-ERK pathway provides numerous opportunities for targeted oncology therapeutics. In particular,the MEK enzyme is attractive due to high selectivity for its target ERK and the central role that activated ERK plays in driving cell proliferation. The structural,pharmacologic,and pharmacokinetic properties of RDEA119/BAY 869766,an allosteric MEK inhibitor,are presented. RDEA119/BAY 869766 is selectively bound directly to an allosteric pocket in the MEK1/2 enzymes. This compound is highly efficacious at inhibiting cell proliferation in several tumor cell lines in vitro. In vivo,RDEA119/BAY 869766 exhibits potent activity in xenograft models of melanoma,colon,and epidermal carcinoma. RDEA119/BAY 869766 exhibits complete suppression of ERK phosphorylation at fully efficacious doses in mice. RDEA119/BAY 869766 shows a tissue selectivity that reduces its potential for central nervous system-related side effects. Using pharmacokinetic and pharmacodynamic data,we show that maintaining adequate MEK inhibition throughout the dosing interval is likely more important than achieving high peak levels because greater efficacy was achieved with more frequent but lower dosing. Based on its longer half-life in humans than in mice,RDEA119/BAY 869766 has the potential for use as a once- or twice-daily oral treatment for cancer. RDEA119/BAY 869766,an exquisitely selective,orally available MEK inhibitor,has been selected for clinical development because of its potency and favorable pharmacokinetic profile.
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产品类型:
产品号#:
73372
73374
产品名:
Refametinib
Ji R-R et al. (SEP 2009)
PLoS computational biology 5 9 e1000512
Transcriptional profiling of the dose response: a more powerful approach for characterizing drug activities.
The dose response curve is the gold standard for measuring the effect of a drug treatment,but is rarely used in genomic scale transcriptional profiling due to perceived obstacles of cost and analysis. One barrier to examining transcriptional dose responses is that existing methods for microarray data analysis can identify patterns,but provide no quantitative pharmacological information. We developed analytical methods that identify transcripts responsive to dose,calculate classical pharmacological parameters such as the EC50,and enable an in-depth analysis of coordinated dose-dependent treatment effects. The approach was applied to a transcriptional profiling study that evaluated four kinase inhibitors (imatinib,nilotinib,dasatinib and PD0325901) across a six-logarithm dose range,using 12 arrays per compound. The transcript responses proved a powerful means to characterize and compare the compounds: the distribution of EC50 values for the transcriptome was linked to specific targets,dose-dependent effects on cellular processes were identified using automated pathway analysis,and a connection was seen between EC50s in standard cellular assays and transcriptional EC50s. Our approach greatly enriches the information that can be obtained from standard transcriptional profiling technology. Moreover,these methods are automated,robust to non-optimized assays,and could be applied to other sources of quantitative data.
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Neuronal store-operated calcium entry pathway as a novel therapeutic target for Huntington's disease treatment.
Huntington's disease (HD) is a neurodegenerative disorder caused by a polyglutamine expansion within Huntingtin (Htt) protein. In the phenotypic screen we identified a class of quinazoline-derived compounds that delayed a progression of a motor phenotype in transgenic Drosophila HD flies. We found that the store-operated calcium (Ca(2+)) entry (SOC) pathway activity is enhanced in neuronal cells expressing mutant Htt and that the identified compounds inhibit SOC pathway in HD neurons. The same compounds exerted neuroprotective effects in glutamate-toxicity assays with YAC128 medium spiny neurons primary cultures. We demonstrated a key role of TRPC1 channels in supporting SOC pathway in HD neurons. We concluded that the TRPC1-mediated neuronal SOC pathway constitutes a novel target for HD treatment and that the identified compounds represent a novel class of therapeutic agents for treatment of HD and possibly other neurodegenerative disorders.
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产品类型:
产品号#:
73352
产品名:
QNZ
Sart S et al. ( 2015)
1283 43--52
Labeling pluripotent stem cell-derived neural progenitors with iron oxide particles for magnetic resonance imaging.
Due to the unlimited proliferation capacity and the unique differentiation ability of pluripotent stem cells (PSCs),including both embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs),large numbers of PSC-derived cell products are in demand for applications in drug screening,disease modeling,and especially cell therapy. In stem cell-based therapy,tracking transplanted cells with magnetic resonance imaging (MRI) has emerged as a powerful technique to reveal cell survival and distribution. This chapter illustrated the basic steps of labeling PSC-derived neural progenitors (NPs) with micron-sized particles of iron oxide (MPIO,0.86 $$m) for MRI analysis. The protocol described PSC expansion and differentiation into NPs,and the labeling of the derived cells either after replating on adherent surface or in suspension. The labeled cells can be analyzed using in vitro MRI analysis. The methods presented here can be easily adapted for cell labeling in cell processing facilities under current Good Manufacturing Practices (cGMP). The iron oxide-labeled NPs can be used for cellular monitoring of in vitro cultures and in vivo transplantation.
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产品类型:
产品号#:
05850
05857
05870
05875
85850
85857
85870
85875
产品名:
mTeSR™1
mTeSR™1
Pei Y et al. (MAR 2015)
Scientific reports 5 9205
A platform for rapid generation of single and multiplexed reporters in human iPSC lines.
Induced pluripotent stem cells (iPSC) are important tools for drug discovery assays and toxicology screens. In this manuscript,we design high efficiency TALEN and ZFN to target two safe harbor sites on chromosome 13 and 19 in a widely available and well-characterized integration-free iPSC line. We show that these sites can be targeted in multiple iPSC lines to generate reporter systems while retaining pluripotent characteristics. We extend this concept to making lineage reporters using a C-terminal targeting strategy to endogenous genes that express in a lineage-specific fashion. Furthermore,we demonstrate that we can develop a master cell line strategy and then use a Cre-recombinase induced cassette exchange strategy to rapidly exchange reporter cassettes to develop new reporter lines in the same isogenic background at high efficiency. Equally important we show that this recombination strategy allows targeting at progenitor cell stages,further increasing the utility of the platform system. The results in concert provide a novel platform for rapidly developing custom single or dual reporter systems for screening assays.
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产品类型:
产品号#:
05850
05857
05870
05875
85850
85857
85870
85875
产品名:
mTeSR™1
mTeSR™1
(May 2025)
Frontiers in Nutrition 12
Generation of bovine iPSCs from fetal fibroblasts for in vitro myogenesis and cultured meat
IntroductionEmerging biotechnologies are increasingly being explored for food production,including the development of cell-cultivated meat. Conventional approaches typically rely on satellite cell (SC) biopsies,which present challenges in scalability. Bovine induced pluripotent stem cells (biPSCs) represent a promising alternative due to their capacity for self-renewal and developmental plasticity.MethodsThis study utilized both lentiviral (integrating) and episomal (non-integrating) reprogramming strategies to generate biPSCs suitable for myogenic differentiation. Bovine fetal fibroblasts (bFFs) were reprogrammed using episomal vectors pMaster K and pCXB-EBNA1,leading to the emergence of putative iPSC colonies 13 days post-nucleofection. A clonal line,bFF-iPSCs pMK,was selected for further analysis.ResultsThe bFF-iPSCs pMK line expressed key pluripotency markers including alkaline phosphatase (AP),OCT4,SOX2,and NANOG,and was stably maintained for over 33 passages,although episomal plasmids remained detectable. in vitro myogenic differentiation was assessed by comparing this line to a previously established lentiviral reprogrammed line (bFF-iPSCs mOSKM). Both lines exhibited downregulation of pluripotency markers and upregulation of the early myogenic marker PAX3. By day 30,the bFF-iPSCs pMK line formed elongated,multinucleated cells characteristic of myotubes and displayed a corresponding gene expression profile.DiscussionThese results provide new insights into bovine in vitro myogenesis and its application in cultured meat production. While promising,the study also highlights the difficulty in achieving complete myogenic differentiation,indicating a need for further optimization of differentiation protocols. Graphical abstract
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产品类型:
产品号#:
85850
85857
产品名:
mTeSR™1
mTeSR™1
(Oct 2024)
Nature Communications 15
Centrioles are frequently amplified in early B cell development but dispensable for humoral immunity
Centrioles define centrosome structure and function. Deregulation of centriole numbers can cause developmental defects and cancer. The p53 tumor suppressor limits the growth of cells lacking or harboring additional centrosomes and can be engaged by the “mitotic surveillance” or the “PIDDosome pathway”,respectively. Here,we show that early B cell progenitors frequently present extra centrioles,ensuing their high proliferative activity and related DNA damage. Extra centrioles are efficiently cleared during B cell maturation. In contrast,centriole loss upon Polo-like kinase 4 (Plk4) deletion causes apoptosis and arrests B cell development. This defect can be rescued by co-deletion of Usp28,a critical component of the mitotic surveillance pathway,that restores cell survival and maturation. Centriole-deficient mature B cells are proliferation competent and mount a humoral immune response. Our findings imply that progenitor B cells are intolerant to centriole loss but permissive to centriole amplification,a feature potentially facilitating their malignant transformation. Centrioles organize chromosome segregation,migration,and the immune synapse. Here,Schapfl et al. show that B cell progenitors tolerate centriole overamplification,but not loss,while mature B cells can mount a humoral immune response in their absence.
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产品类型:
产品号#:
19854
19854RF
产品名:
EasySep™小鼠B细胞分选试剂盒
RoboSep™ 小鼠B细胞分选试剂盒
(Oct 2024)
Journal of Translational Medicine 22 10299
FANCA promotes lung adenocarcinoma progression and is a potential target for epitope vaccine immunotherapy
BackgroundFANCA mutations have been detected in a variety of cancers and found to be pro-carcinogenic. However,no functional studies have been identified regarding the involvement of FANCA in the occurrence and the immune response of LUAD.MethodsThe mRNA expression and overall survival rates of FANCA were evaluated by the TIMER,PrognoScan and TCGA database in LUAD tissues,and FANCA expression was further validated by clinical serum samples using ELISA. The correlation between FANCA and immune infiltration level was investigated via TISIDB database and CIBERSORT algorithm. The Kaplan–Meier plotter was used to further evaluate the prognostic value based on the expression levels of FANCA in related immune cells. Then,the influence of FANCA knockout on the proliferation,migration,and invasion of A549 and H1299 cells was validated using CCK8,cloning formation,and Transwell assays. Subsequently,HLA-A2-restricted FANCA antigenic peptides were predicted and synthesized by NetMHC4.0 and SYFPEITHI,and DCs were induced and cultured in vitro. Finally,DCs loaded with HLA-A2-restricted FANCA antigenic peptides were co-cultured with autologous peripheral blood lymphocyte to generate specific CTLs. The killing effects of different CTLs on LUAD cells were studied.ResultsThe results showed that high levels of FANCA in patients with LUAD were significantly correlated with worse OS survival,which was correlated with age,clinical stage,pathological T stage,M stage,and N stage in LUAD. Knockdown of FANCA in A549 and H1299 cells significantly inhibited proliferation,metastasis,and invasion in vitro. In addition,FANCA was significantly related to immune infiltrate,genomic alterations and TMB. FANCA expression infuenced the prognosis of LUAD patients by directly affecting immune cell infltration. Finally,HLA-A2-restricted FANCA antigenic peptides were synthesized. And FANCA 146–154 (SLLEFAQYL) antigenic peptide exhibit a stronger affinity for DCs,and induce CTLs to produce stronger targeted killing ability for LUAD cells at an effector-to-target ratio of 40:1.ConclusionThese results demonstrated that the elevation of FANCA promotes malignant phenotype of LUAD,and the potential peptide P2 (SLLEFAQYL) derived from FANCA may be used as an epitope vaccine for the treatment of LUAD.
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