这项工作是由美国国立卫生研究院主任的新的创新奖计划（ED）的赠款支持。 AA是由美国国家癌症研究所和美国国家科学基金会本科奖项部分支持。

1.使病毒载体为感兴趣的基因，以及阳性和阴性对照的编码序列，插入pBABEpuro通过传统的克隆方法（PCR扩增，限制性消化和连接）。上有矢量4的限制性位点，其中该DNA可被插入：BamHI位，SnaBI位，EcoRI和SalI位。 <ol><li>从准备使用QIAGEN质粒Midi试剂盒感受态细胞转染级质粒DNA。 </li><li>使用NanoDrop2000分光光度计测量DNA浓度。 </li></ol> 2.逆转录病毒生产该开发平台-E包装细胞系将被用于产生亲嗜性逆转录病毒，将提供感兴趣的NIH 3T3细胞中的cDNA。 <ol><li>建立从冷冻细胞开发平台-E培养<ol><li>迅速解冻开发平台-E细胞在37℃水浴并转移到一个15毫升的锥形管。慢慢加入9毫升开发平台-E介质（杜lbecco改进的Eagle培养基（DMEM）+ 10％胎牛血清（FBS）+青霉素和链霉素）。 </li><li>离心管，在180× 克5分钟，并弃去上清液。 </li><li>重新悬浮细胞用10ml开发平台-E培养基并转移到10cm的培养皿中。 </li><li>孵育所述细胞在37℃，5％CO 2的培养箱中，直到它们80-90％汇合（约2天）。 </li></ol></li><li>细胞分裂<ol><li>吸出培养基，用PBS洗一次细胞。 </li><li>加2ml的0.05％胰蛋白酶-EDTA和孵化在室温1分钟。 </li><li>分离攻丝细胞通过手指，加入10 mL开发平台-E培养基中，将细胞悬液转移到15毫升管。 </li><li>离心管，在180× 克5分钟，并弃去上清液。 </li><li>悬浮细胞10毫升开发平台-E介质和种子在他们的新菜，在1：4-1：6稀释。 </li></ol></li><li>开发平台-E播种和转染<ol><li>种子2×10 6个细胞每使用开发平台-E中无任何抗生素10厘米培养皿。 </li><li>孵育在37°C，5％ 二氧化碳培养箱细胞O / N。 </li><li>次日，转移300微升的Opti-MEM的入1.5mL微管中。 </li><li>添加27微升的聚乙烯亚胺（PEI），具有成本效益的转染试剂12，向制备的管的Opti-MEM。通过手指敲击轻轻混匀，并培育5分钟在室温。 </li><li>添加9微克染同类的质粒DNA导入的Opti-MEM / PEI管，通过涡旋轻轻混匀，并孵育15分钟，在室温。 </li><li>添加DNA / PEI复杂滴进开发平台-E盘，孵化O / N在37℃，5％CO 2。 </li><li>第二天，吸出含有转染试剂的培养基中，并添加10ml新鲜开发平台-E培养基（无抗生素）。 </li><li>返回的细胞培养箱。 </li></ol></li></ol> 3. NIH 3T3细胞和病毒感染<ol><li>建立NIH3T3文化和播<ol><li>迅速解冻NIH 3T3细胞在37℃水浴中，并转移到15毫升管。慢慢加入9毫升NIH 3T3培养基（DMEM + 10％FBS）的。 </li><li>离心管，在180× 克5分钟，并弃去上清液。 </li><li>将细胞重悬于10毫升NIH 3T3介质和传输到10cm的培养皿中。 </li><li>孵育在37℃，5％CO 2培养箱中的细胞。这是非常重要的是，NIH 3T3细胞始终保持underconfluent（50-60％），作为自发变换（和灶形成的，因此基础水平）的频率增加，一旦培养达到汇合。 </li><li>每10 cm培养皿种子3×10 5细胞，并培育O / N感染的第二天。 </li></ol></li><li>感染<ol><li>通过使用10ml的一次性注射器，通过0.45μm孔径的尼龙膜过滤器过滤它，并将其转移到一个15毫升的收获从开发平台-E盘的逆转录病毒上清液管。 </li><li>加入10毫升新鲜开发平台-E中的细胞（无抗生素），并将其返回到孵化器。 </li><li>吸从NIH 3T3细胞中盘被感染的介质，并加入5ml含病毒过滤的上清液的定期NIH 3T3介质和5毫升。 </li><li>加入聚凝胺至培养皿以6微克/ ml的浓度。 </li><li>孵育细胞在o / n 37℃下，5％的CO 2。 </li><li>第二天，重复步骤3.2.1 - 3.2.5第二轮感染。 </li><li>更换含有病毒的培养基定期NIH 3T3中。 </li><li>允许在NIH 3T3细胞中生长2-3周，更换培养基是必要的。检查的目的蛋白质的表达通过常规蛋白电泳和免疫印迹上从复制平板全细胞裂解液。 </li></ol></li></ol> 4.染色和定量<ol><li>结晶紫染色<ol><li>吸出NIH 3T3中，将菜在冰上。 </li><li>用冰冷的PBS两次洗碗。 </li><li>固定的细胞用冰冷的甲醇中10分钟。 </li><li>从冰取出盘子，吸出甲醇，并加入3毫升0.5％结晶紫溶液中的​​25％甲醇（RT）下进行。 </li><li>孵育菜为5分钟在室温。 </li><li>吸出的结晶紫溶液并小心地冲洗用Milli-Q H 2 O的培养皿直至没有颜色在漂洗脱落。 </li><li>让菜干O / N在工作台上（发现）。 </li></ol></li><li>佛慈定量<ol><li>一旦菜是干的，用尺子来测量上盘细胞的深颜色的集合。只计数那些大于5毫米，直径为“焦点”。记录病灶的数量，并计算平均值和与对照相比的显着性。 </li></ol></li></ol>

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作者什么都没有透露。

在FFA提供了一种快速简便的方法来评估在体外恶性转化。它是适合于相对大数目的候选基因的筛选，并且其适度的技术要求，使其符合成本效益。此外，两个或多个基因可以共表达（有时被称为一个“合作”测定）来评价该组合的致瘤潜力。该测定的优势依赖于它的简单的技术，其易于定量和它的相对短的周转时间。然而，必须强调的是，它不构成所有的体外测定法的限制。该测定?...

肿瘤细胞可以从他们的正常对应来区分由范围广泛的改变，从基因表达模式以表观基因组形态学和增生性改变。在后者，降低血清依赖性，接触（密度）抑制损失，收购的锚定非依赖性增殖，最终，当注射到动物形成肿瘤的能力是恶变3是有用的，可衡量的指标。几种体外和体内试验已经开发了用于细胞转化， 在体外测定的目的是识别测定改变培养形态（焦点形成实验），培养动力学（生长率，饱和密度）和生长因子（生长血清减少的）或锚地（生长在软琼脂）的要求。的黄金标准，用于确定细胞类型的恶性性质仍然肿瘤形成（异种移植物）中的实验动物。然而，T他花费和体内研究的长度并不总是使它们正当作为候选癌基因的第一个验证步骤或筛选。虽然没有在体外测定提供了一个基因的致癌潜力的一个明确的评估，它们提供的洞察致癌潜力，可能在体内研究缩小将来。其中最广泛使用的系统，用于在体外评估致癌潜力的是焦点形成分析2。这种方法依赖于使用的NIH 3T3小鼠成纤维细胞，非转化细胞系，显示强烈的接触抑制。在密度依赖性生长的丧失的癌基因的过度表达的结果;然后转化的细胞可以生长在多个层，形成“病灶”，很容易地可视化对未转化细胞的背景单层。焦点形成分析，那么，衡量一个候选人癌基因的能力引起恶变，就证明了接触INHIB损失银行足球比赛作为衡量的表型。 FFA的已使用蛋白激酶的过表达（ 例如 ，Src蛋白4，BRAF 5），转录因子（ 例如 ，N--myc基因6），G-蛋白偶联受体（ 例如 ，P2RY8 7）和GTP酶（ 例如 ，以评估转换，拉斯1），等等。相对容易此测定的使得它一个很好的选择，这将提供一个快速和视觉上明确的答案的基因的过表达是否足以转化的NIH 3T3小鼠成纤维细胞在体外 。 在这个协议中所描述的FFA使用开发平台-E包装细胞系8，它提供了病毒包装蛋白和逆转录病毒载体pBABEpuro 9（Addgene质粒1764）产生逆转录病毒。转染用含有感兴趣的基因的pBABEpuro构建体后，将开发平台-E的细胞系将产生亲嗜性逆转录病毒可以用于感染的NIH 3T3细胞。牛逼基因传递，他的病毒的方法比传统的化学转染方法更高效，它提供了一种可持续表达基因10。一旦掺入NIH 3T3细胞的基因组中，所关注的基因的过表达是由病毒长末端重复序列（LTR）启动子11驱动。这个常量表达式可以被用来确定感兴趣的基因是否具有致癌活性，如通过形成病灶，在NIH 3T3细胞测定。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">pBABE-puro vector</td>
			<td style="width:127px;">Addgene</td>
			<td style="width:123px;">Plasmid 1764</td>
			<td style="width:171px;">cloning vector</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Platinum-E Retroviral Packaging Cell Line, Ecotropic</td>
			<td style="width:127px;">Cell Biolabs, Inc.</td>
			<td style="width:123px;">RV-101</td>
			<td>cell line for viral production</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">NIH 3T3 Cell Line murine</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td style="width:123px;">93061524</td>
			<td>cell line for focus formation assay</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">10 mL BD Luer-Lok tip syringe</td>
			<td style="width:127px;">BD Biosciences</td>
			<td style="width:123px;">309604</td>
			<td>viral production reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">0.45 &#956;m Puradisc Syringe Filter</td>
			<td style="width:127px;">Whatman</td>
			<td style="width:123px;">6750-2504</td>
			<td>viral production reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Polyethylenimine (PEI)</td>
			<td style="width:127px;">Polysciences, Inc.</td>
			<td style="width:123px;">23966-2</td>
			<td>cell transfection reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Polybrene Infection / Transfection Reagent</td>
			<td style="width:127px;">EMD Millipore</td>
			<td style="width:123px;">TR-1003-G</td>
			<td>cell transfection reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Crystal Violet</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td style="width:123px;">C581-25</td>
			<td>cell stain reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Plasmid Plus Midi Kit</td>
			<td style="width:127px;">QIAGEN</td>
			<td style="width:123px;">12945</td>
			<td>plasmid purification</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">BD Falcon Tissue Culture Dishes</td>
			<td style="width:127px;">BD Biosciences</td>
			<td style="width:123px;">353003</td>
			<td>cell culture supplies</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Dulbecco&#39;s Modified Eagle Medium (DMEM)</td>
			<td style="width:127px;">Gibco</td>
			<td style="width:123px;">11995-065</td>
			<td>cell culture media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">0.05% Trypsin-EDTA</td>
			<td style="width:127px;">Gibco</td>
			<td style="width:123px;">25300-054</td>
			<td>cell culture supplies</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Opti-MEM I Reduced Serum Medium</td>
			<td style="width:127px;">Gibco</td>
			<td style="width:123px;">31985-062</td>
			<td>cell culture media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Fetal Bovine Serum (FBS)</td>
			<td style="width:127px;">Gibco</td>
			<td style="width:123px;">16000-044</td>
			<td>cell culture media</td>
		</tr>
	</tbody>
</table>

focus formation: a cell-based assay to determine the oncogenic potential of a gene

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent growth potential, and the ability to form tumors in experimental animals1. In NIH 3T3 cells, the Ras signal transduction pathway is known to trigger many of these events, what is known as Ras transformation. The introduction of an overexpressed gene in NIH 3T3 cells may promote morphological transformation and loss of contact inhibition, which can help determine the oncogenic potential of that gene of interest. An assay that provides a straightforward method to assess one aspect of the transforming potential of an oncogene is the Focus Formation Assay (FFA)2. When NIH 3T3 cells divide normally in culture, they do so until they reach a confluent monolayer. However, in the presence of an overexpressed oncogene, these cells can begin to grow in dense, multilayered foci1 that can be visualized and quantified by crystal violet or Hema 3 staining. In this article we describe the FFA protocol with retroviral transduction of the gene of interest into NIH 3T3 cells, and how to quantify the number of foci through staining. Retroviral transduction offers a more efficient method of gene delivery than transfection, and the use of an ecotropic murine retrovirus provides a biosafety control when working with potential human oncogenes.

MXD3是一个基本的螺旋 - 环 - 螺旋亮氨酸拉链（bHLHZ）转录因子是这样的MYC / MAX / MAD网络中的成员。它是MAD家族13-15的非典型构件，并且它已经被报道参与致癌16,17。相比pBABEpuro（阴性对照）和MYC（阳性对照），美国国立卫生研究院3T3菜肴其中MXD3过表达有显著更少灶（ 图1A）。在图1B中的数据是从多个实验收集的，以确定显着性。 有确?...

Watch this Scientific Journal Video about Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene at JoVE.com

Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene

聚焦形成分析提供了一个简单的方法来评估候选基因的转化潜力。

注重形成：一个基于Cell的检测，以确定一个基因的致癌性

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent ...

focus-formation-cell-based-assay-to-determine-oncogenic-potential

Research

JoVE Journal

Medicine

27.7K 次观看.  University of California, Davis. 聚焦形成分析提供了一个简单的方法来评估候选基因的转化潜力。 

视频: Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene

Biomarkers in an Animal Model for Revealing Neural, Hematologic, and Behavioral Correlates of PTSD

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for objective diagnosis but also for the evaluation of therapeutic efficacy and resilience to trauma. Ongoing research is directed at identifying molecular biomarkers for PTSD, including traumatic stress induced proteins, transcriptomes, genomic variances and genetic modulators, using biologic samples from subjects' blood, saliva, urine, and postmortem brain tissues. However, the correlation of these biomarker molecules in peripheral or postmortem samples to altered brain functions associated with psychiatric symptoms in PTSD remains unresolved. Here, we present an animal model of PTSD in which both peripheral blood and central brain biomarkers, as well as behavioral phenotype, can be collected and measured, thus providing the needed correlation of the central biomarkers of PTSD, which are mechanistic and pathognomonic but cannot be collected from people, with the peripheral biomarkers and behavioral phenotypes, which can.
Our animal model of PTSD employs restraint and tail shocks repeated for three continuous days - the inescapable tail-shock model (ITS) in rats. This ITS model mimics the pathophysiology of PTSD 17, 7, 4, 10. We and others have verified that the ITS model induces behavioral and neurobiological alterations similar to those found in PTSD subjects 17, 7, 10, 9. Specifically, these stressed rats exhibit (1) a delayed and exaggerated startle response appearing several days after stressor cessation, which given the compressed time scale of the rat's life compared to a humans, corresponds to the one to three months delay of symptoms in PTSD patients (DSM-IV-TR PTSD Criterian D/E 13), (2) enhanced plasma corticosterone (CORT) for several days, indicating compromise of the hypothalamopituitary axis (HPA), and (3) retarded body weight gain after stressor cessation, indicating dysfunction of metabolic regulation.
The experimental paradigms employed for this model are: (1) a learned helplessness paradigm in the rat assayed by measurement of acoustic startle response (ASR) and a charting of body mass; (2) microdissection of the rat brain into regions and nuclei; (3) enzyme-linked immunosorbent assay (ELISA) for blood levels of CORT; (4) a gene expression microarray plus related bioinformatics tools 18. This microarray, dubbed rMNChip, focuses on mitochondrial and mitochondria-related nuclear genes in the rat so as to specifically address the neuronal bioenergetics hypothesized to be involved in PTSD.

We describe a rat model of post traumatic stress disorder (PTSD) that reveals the persistent alterations in neuroendocrine function and the delayed long-term, exaggerated fear response, characteristic of PTSD patients. The animal model and methods described here are useful for correlating biomarkers in brain nuclei, which are mechanistic but cannot be measured in patients, with biomarkers in peripheral white blood cells, which can.

在动物模型揭示神经，血液，创伤后应激障碍和行为相关因素的生物标志物

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for ...

科研

医学

A Novel Surgical Approach for Intratracheal Administration of Bioactive Agents in a Fetal Mouse Model

Prenatal pulmonary delivery of cells, genes or pharmacologic agents could provide the basis for new therapeutic strategies for a variety of genetic and acquired diseases. Apart from congenital or inherited abnormalities with the requirement for long-term expression of the delivered gene, several non-inherited perinatal conditions, where short-term gene expression or pharmacological intervention is sufficient to achieve therapeutic effects, are considered as potential future indications for this kind of approach. Candidate diseases for the application of short-term prenatal therapy could be the transient neonatal deficiency of surfactant protein B causing neonatal respiratory distress syndrome1,2 or hyperoxic injuries of the neonatal lung3. Candidate diseases for permanent therapeutic correction are Cystic Fibrosis (CF)4, genetic variants of surfactant deficiencies5 and &alpha;1-antitrypsin deficiency6.
Generally, an important advantage of prenatal gene therapy is the ability to start therapeutic intervention early in development, at or even prior to clinical manifestations in the patient, thus preventing irreparable damage to the individual. In addition, fetal organs have an increased cell proliferation rate as compared to adult organs, which could allow a more efficient gene or stem cell transfer into the fetus. Furthermore, in utero gene delivery is performed when the individual's immune system is not completely mature. Therefore, transplantation of heterologous cells or supplementation of a non-functional or absent protein with a correct version should not cause immune sensitization to the cell, vector or transgene product, which has recently been proven to be the case with both cellular and genetic therapies7.
In the present study, we investigated the potential to directly target the fetal trachea in a mouse model. This procedure is in use in larger animal models such as rabbits and sheep8, and even in a clinical setting9, but has to date not been performed before in a mouse model. When studying the potential of fetal gene therapy for genetic diseases such as CF, the mouse model is very useful as a first proof-of-concept because of the wide availability of different transgenic mouse strains, the well documented embryogenesis and fetal development, less stringent ethical regulations, short gestation and the large litter size.
Different access routes have been described to target the fetal rodent lung, including intra-amniotic injection10-12, (ultrasound-guided) intrapulmonary injection13,14 and intravenous administration into the yolk sac vessels15,16 or umbilical vein17. Our novel surgical procedure enables researchers to inject the agent of choice directly into the fetal mouse trachea which allows for a more efficient delivery to the airways than existing techniques18.

We developed a novel surgical approach for intratracheal administration of bioactive agents into the mouse fetus. The delivery route is more efficient in targeting the fetal mouse lungs than the commonly used intra-amniotic injection. This procedure has to date not been described in a mouse model.

一种新的手术方法气管内注射生物活性剂在胎鼠模型

Prenatal pulmonary delivery of cells, genes or pharmacologic agents could provide the basis for new therapeutic strategies for a variety of genetic and ...

High-throughput Flow Cytometry Cell-based Assay to Detect Antibodies to N-Methyl-D-aspartate Receptor or Dopamine-2 Receptor in Human Serum

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders.

Over the recent years, live cell-based assays have been used successfully to detect antibodies against surface and conformational antigens. Here, we describe a method using high-throughput flow cytometry enabling the analysis of large cohorts of patients. Detection of novel antibodies will improve diagnosis and treatment of immune-mediated disorders.

高通量流式细胞仪检测细胞为基础的试验检测抗体，以N-甲基-D-天冬氨酸受体或多巴胺2受体在人血清

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases ...

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the actual molecules towards which the cells migrate remain elusive. This modified invasion assay has been developed to identify targets which drive cell migration and invasion. This technique compares the invasion index under three conditions to determine whether a specific hormone, growth factor, or cytokine plays a role in mediating the invasive potential of a cancer cell. These conditions include i) normal fetal bovine serum (FBS), ii) charcoal-stripped FBS (CS-FBS), which removes hormones, growth factors, and cytokines and iii) CS-FBS + molecule (denoted &#8220;X&#8221;). A significant change in cell invasion with CS-FBS as compared to FBS, indicates the involvement of hormones, cytokines or growth factors in mediating the change. Individual molecules can then be added back to CS-FBS to assay their ability to reverse or rescue the invasion phenotype. Furthermore, two or more factors can be combined to evaluate the additive or synergistic effects of multiple molecules in driving or inhibiting invasion. Overall, this method enables the investigator to determine whether hormones, cytokines, and/or growth factors play a role in cell invasion by serving as chemoattractants or inhibitors of invasion for a particular type of cancer cell or a specific mutant. By identifying specific chemoattractants and inhibitors, this modified invasion assay may help to elucidate signaling pathways that direct cancer cell invasion.

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

This video article describes a modified in vitro method to examine the role of hormones, cytokines and/or growth factors in driving cancer cell invasion.

一种改进<em&gt;在体外</em&gt;入侵检测，以确定激素，在调节肿瘤细胞侵袭的细胞因子和/或生长因子的潜在作用

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the ...

A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders

Differentiation and activation of osteoclasts play a key role in the development of musculoskeletal diseases as these cells are primarily involved in bone resorption. Osteoclasts can be generated in vitro from monocyte/macrophage precursor cells in the presence of certain cytokines, which promote survival and differentiation. Here, both in vivo and in vitro techniques are demonstrated, which allow scientists to study different cytokine contributions towards osteoclast differentiation, signaling, and activation. The minicircle DNA delivery gene transfer system provides an alternative method to establish an osteoporosis-related model is particularly useful to study the efficacy of various pharmacological inhibitors in vivo. Similarly, in vitro culturing protocols for producing osteoclasts from human precursor cells in the presence of specific cytokines enables scientists to study osteoclastogenesis in human cells for translational applications. Combined, these techniques have the potential to accelerate drug discovery efforts for osteoclast-specific targeted therapeutics, which may benefit millions of osteoporosis and arthritis patients worldwide.

A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders

Differentiation of precursor cells into osteoclasts is regulated by cytokines and growth factors. Here, a novel gene transfer technique for differentiation of osteoclasts in vivo and cell culture protocols for differentiating precursor cells into osteoclasts in vitro as a method to study the effects of cytokines on osteoclastogenesis are described.

一种新型的<em&gt;在体内</em&gt;基因转移技术和<em&gt;在体外</em&gt;细胞分析为肌肉骨骼疾病骨质流失的研究

Differentiation and activation of osteoclasts play a key role in the development of musculoskeletal diseases as these cells are primarily involved in bone ...

Three-Dimensional (3D) Tumor Spheroid Invasion Assay

Invasion of surrounding normal tissues is generally considered to be a key hallmark of malignant (as opposed to benign) tumors. For some cancers in particular (e.g., brain tumors such as glioblastoma multiforme and squamous cell carcinoma of the head and neck &#8211; SCCHN) it is a cause of severe morbidity and can be life-threatening even in the absence of distant metastases. In addition, cancers which have relapsed following treatment unfortunately often present with a more aggressive phenotype. Therefore, there is an opportunity to target the process of invasion to provide novel therapies that could be complementary to standard anti-proliferative agents. Until now, this strategy has been hampered by the lack of robust, reproducible assays suitable for a detailed analysis of invasion and for drug screening. Here we provide a simple micro-plate method (based on uniform, self-assembling 3D tumor spheroids) which has great potential for such studies. We exemplify the assay platform using a human glioblastoma cell line and also an SCCHN model where the development of resistance against targeted epidermal growth factor receptor (EGFR) inhibitors is associated with enhanced matrix-invasive potential. We also provide two alternative methods of semi-automated quantification: one using an imaging cytometer and a second which simply requires standard microscopy and image capture with digital image analysis.

Three-Dimensional 3D Tumor Spheroid Invasion Assay

Invasion of surrounding normal tissues is a defining characteristic of malignant tumors. We provide here a simple, semi-automated micro-plate assay of invasion into a natural 3D biomatrix that has been exemplified with a number of models of advanced human cancers.

三维（3D）肿瘤球体侵袭试验

Invasion of surrounding normal tissues is generally considered to be a key hallmark of malignant (as opposed to benign) tumors. For some cancers in ...

Utilization of the Soft Agar Colony Formation Assay to Identify Inhibitors of Tumorigenicity in Breast Cancer Cells

Given the inherent difficulties in investigating the mechanisms of tumor progression in vivo, cell-based assays such as the soft agar colony formation assay (hereafter called soft agar assay), which measures the ability of cells to proliferate in semi-solid matrices, remain a hallmark of cancer research. A key advantage of this technique over conventional 2D monolayer or 3D spheroid cell culture assays is the close mimicry of the 3D cellular environment to that seen in vivo. Importantly, the soft agar assay also provides an ideal tool to rigorously test the effects of novel compounds or treatment conditions on cell proliferation and migration. Additionally, this assay enables the quantitative assessment of cell transformation potential within the context of genetic perturbations. We recently identified peptidylarginine deiminase 2 (PADI2) as a potential breast cancer biomarker and therapeutic target. Here we highlight the utility of the soft agar assay for preclinical anti-cancer studies by testing the effects of the PADI inhibitor, BB-Cl-amidine (BB-CLA), on the tumorigenicity of human ductal carcinoma in situ (MCF10DCIS) cells.

Here, we document the use of the soft agar colony formation assay to test the effects of a peptidylarginine deiminase (PADI) enzyme inhibitor, BB-Cl-amidine, on breast cancer tumorigenicity in vitro.

软琼脂集落形成实验利用识别的致瘤性乳腺癌细胞抑制剂

Given the inherent difficulties in investigating the mechanisms of tumor progression in vivo, cell-based assays such as the soft agar colony formation ...

TRUE Gene Silencing: Screening of a Heptamer-type Small Guide RNA Library for Potential Cancer Therapeutic Agents

TRUE gene silencing (termed after tRNase ZL-utilizing efficacious gene silencing) is one of the RNA-directed gene silencing technologies, which utilizes an artificial small guide RNA (sgRNA) to guide tRNA 3&#8242; processing endoribonuclease, tRNase ZL, to recognize a target RNA. sgRNAs can be taken up by cells without any transfection reagents and can downregulate their target RNA levels and/or induce apoptosis in human cancer cells. We have screened an sgRNA library containing 156 heptamer-type sgRNAs for the effect on viability of human myeloma and leukemia cells, and found that 20 of them can efficiently induce apoptosis in at least one of the cancer cell lines. Here we present a protocol for screening of a heptamer-type sgRNA library for potential therapeutic drugs against blood cancers. The protocol includes how to construct the sgRNA library, how to assess the effect of each sgRNA on cell viability, and how to further evaluate the effective sgRNAs by flow cytometry. Around 2,000 hits would be expected to be obtained by screening the full-scale sgRNA library composed of 16,384 heptamers.

Here we present a protocol for screening of a heptamer-type sgRNA library for potential therapeutic drugs against blood cancers.

TRUE基因沉默：一个七聚物型小导RNA库的筛选潜在的癌症治疗药

TRUE gene silencing (termed after tRNase ZL-utilizing efficacious gene silencing) is one of the RNA-directed gene silencing technologies, which utilizes ...

Injection of Syngeneic Murine Melanoma Cells to Determine Their Metastatic Potential in the Lungs

Approximately 90% of human cancer deaths are linked to metastasis. Despite the prevalence and relative harm of metastasis, therapeutics for treatment or prevention are lacking. We report a method for the establishment of pulmonary metastases in mice, useful for the study of this phenomenon. Tail vein injection of B57BL/6J mice with B16-BL6 is among the most used models for melanoma metastases. Some of the circulating tumor cells establish themselves in the lungs of the mouse, creating "experimental" metastatic foci. With this model it is possible to measure the relative effects of therapeutic agents on the development of cancer metastasis. The difference in enumerated lung foci between treated and untreated mice indicates the efficacy of metastases neutralization. However, prior to the investigation of a therapeutic agent, it is necessary to determine an optimal number of injected B16-BL6 cells for the quantitative analysis of metastatic foci. Injection of too many cells may result in an overabundance of metastatic foci, impairing proper quantification and overwhelming the effects of anti-cancer therapies, while injection of too few cells will hinder the comparison between treated and controls.

Metastasis plays a profound role in the virulence of cancer, accounting for an estimated 90% of deaths. We report a protocol for a metastatic melanoma model in mice that is useful for determining the efficacy of therapeutic agents against this clinical phenomenon.

同基因小鼠黑色素瘤细胞注射，以确定其在肺转移潜能

Approximately 90% of human cancer deaths are linked to metastasis.  Despite the prevalence and relative harm of metastasis, therapeutics for treatment or ...

A Choroid Plexus Epithelial Cell-based Model of the Human Blood-Cerebrospinal Fluid Barrier to Study Bacterial Infection from the Basolateral Side

The epithelial cells of the choroid plexus (CP), located in the ventricular system of the brain, form the blood-cerebrospinal fluid barrier (BCSFB). The BCSFB functions in separating the cerebrospinal fluid (CSF) from the blood and restricting the molecular exchange to a minimum extent. An in vitro model of the BCSFB is based on cells derived from a human choroid plexus papilloma (HIBCPP). HIBCPP cells display typical barrier functions including formation of tight junctions (TJs), development of a transepithelial electrical resistance (TEER), as well as minor permeabilities for macromolecules. There are several pathogens that can enter the central nervous system (CNS) via the BCSFB and subsequently cause severe disease like meningitis. One of these pathogens is Neisseria meningitidis (N. meningitidis), a human-specific bacterium. Employing the HIBCPP cells in an inverted cell culture filter insert system enables to study interactions of pathogens with cells of the BCSFB from the basolateral cell side, which is relevant in vivo. In this article, we describe seeding and culturing of HIBCPP cells on cell culture inserts. Further, infection of the cells with N. meningitidis along with analysis of invaded and adhered bacteria via double immunofluorescence is demonstrated. As the cells of the CP are also involved in other diseases, including neurodegenerative disorders like Alzheimer`s disease and Multiple Sclerosis, as well as during the brain metastasis of tumor cells, the model system can also be applied in other fields of research. It provides the potential to decipher molecular mechanisms and to identify novel therapeutic targets.

The epithelial cells of the choroid plexus (CP) form the blood-cerebrospinal fluid barrier (BCSFB). An in vitro model of the BCSFB employs human choroid plexus papilloma (HIBCPP) cells. This article describes culturing and basolateral infection of HIBCPP cells using a cell culture filter insert system.

人体血液，脑脊液屏障的脉络丛上皮基于Cell的产品型号从基底外侧面研究细菌感染

The epithelial cells of the choroid plexus (CP), located in the ventricular system of the brain, form the blood-cerebrospinal fluid barrier (BCSFB). The ...