この作品は、NIHのディレクターの新イノベーター賞プログラム（ED）からの助成金によってサポートされていました。 AAは国立がん研究所、国立科学財団からの学部賞によって部分的にサポートされていました。

1.ウイルスベクターを作る目的の遺伝子、ならびに陽性および陰性対照のためのコード配列は、従来のクローニング法（PCR増幅、制限消化およびライゲーション）によってpBABEpuroに挿入される。 BamHIでSnaBIで、EcoRIおよびSalIで：DNAを挿入することができるベクター上の4つの制限部位がある。 <ol><li> QIAGENプラスミドミディキットを使用してコンピテント細胞からトランスフェクショングレードのプラスミドDNAを準備します。 </li><li> NanoDrop2000分光光度計を用いてDNA濃度を測定します。 </li></ol> 2.レトロウイルス生産のPlat-Eパッケージング細胞株は、NIH 3T3細胞に目的のcDNAを送達するエコトロピックレトロウイルスを産生するために使用される。 <ol><li>凍結細胞からのPlat-Eの文化の確立<ol><li>すぐに37℃の水浴中でのPlat-E細胞を解凍し、15mlのコニカルチューブに移す。ゆっくりとのPlat-E培地9ml（デュを追加lbecco改変イーグル培地（DMEM）+ 10％ウシ胎児血清（FBS）+ペニシリン及びストレプトマイシン）。 </li><li> 180 xでのチューブを遠心 gで5分間、上清を捨てる。 </li><li>再懸濁のPlat-E培地及び10cmの培養皿に移し、10 mlの細胞。 </li><li>それらは80〜90％コンフルエント（約2日）になるまで37℃、5％CO 2インキュベーター中で細胞をインキュベートする。 </li></ol></li><li>セル分割<ol><li>メディアを吸引除去し、PBSで細胞を1回洗浄します。 </li><li> 0.05％トリプシンEDTAの2ミリリットルを加え、室温で1分間インキュベートする。 </li><li>指タッピングによって細胞を剥離、ぷらっと-E培地10mlを追加し、15ミリリットルチューブに細胞懸濁液を移す。 </li><li> 180 xでのチューブを遠心 gで5分間、上清を捨てる。 </li><li>ぷらっと-E培地10mlで細胞を再懸濁し、1から新しい料理でそれらをシード：4-1：6の希釈。 </li></ol></li><li> PLAT-Eシードおよびトランスフェクション<ol><li>シード2×10 6任意の抗生物質を含まないのPlat-E培地を用いて10cmの培養皿当たり細胞。 </li><li> 37℃、5％CO 2インキュベーター中で細胞をO / Nでインキュベートする。 </li><li>翌日、1.5mlマイクロチューブにのOpti-MEM300μlのを転送する。 </li><li>のOpti-MEMでプリペアチューブに、ポリエチレンイミンの27μL（PEI）、費用対効果の高いトランスフェクション試薬12を追加します。指タッピングにより穏やかに混合し、室温で5分間インキュベートする。 </li><li> 、のOpti-MEM / PEIチューブにトランスフェクショングレードのプラスミドDNAの9μgのを追加し、ボルテックスにより穏やかに混合し、室温で15分間インキュベートする。 </li><li>追加DNA / PEIのPlat-E皿に、37℃でO / Nインキュベート複雑なワイズドロップ、5％のCO 2。 </li><li>翌日、トランスフェクション試薬を含む培地を吸引し、（抗生物質を含まない）新鮮なのPlat-E培地10mlを追加します。 </li><li>インキュベーターにセルを返します。 </li></ol></li></ol> 3. NIH 3T3細胞と感染<ol><li> NIHの確立3T3文化や播種<ol><li>すぐに37℃の水浴中でNIH 3T3細胞を解凍し、15mlチューブに移す。ゆっくりとNIH 3T3培地（DMEM + 10％FBS）の9ミリリットルを追加します。 </li><li> 180 xでのチューブを遠心 gで5分間、上清を捨てる。 </li><li> 10cmの培養皿にNIH 3T3媒体と転送10mlで細胞を再懸濁。 </li><li> 37℃、5％CO 2インキュベーター中で細胞をインキュベートする。これは、自発的な変換（および病巣形成の、したがって基礎レベル）の周波数として文化がコンフルエントに達すると増加、NIH 3T3細胞は常にunderconfluent（百分の50から60）を保持していることが非常に重要です。 </li><li>シード3×10 10 cmディッシュあたり5個の細胞と、翌日感染のためにO / Nインキュベートする。 </li></ol></li><li>感染<ol><li>孔径0.45μmのナイロン膜フィルターを介して濾過する10mlの使い捨てシリンジを使用し、そして15mlにそれを転送することによってのPlat-E皿からレトロウイルス上清を収穫チューブ。 </li><li> （抗生物質を含まない）を細胞に新鮮なのPlat-E培地10mlを追加し、インキュベーターに戻す。 </li><li>感染していることがNIH 3T3細胞ディッシュから培地を吸引し、ウイルス含有濾過した上清の5の正規NIH 3T3培地1mlと5ミリリットルを追加します。 </li><li> 610μg/ mlの濃度で、皿にポリブレンを追加します。 </li><li> 37℃、5％CO 2で細胞をO / Nでインキュベートする。 </li><li>感染の第二ラウンドのために3.2.5 - 次の日、繰り返して3.2.1を繰り返します。 </li><li>定期的なNIH 3T3培地でウイルス含有培地を交換してください。 </li><li> NIH 3T3細胞は、必要に応じて培地を交換、2-3週間成長できるようにします。レプリカプレートから全細胞溶解物に従来のタンパク質電気泳動およびイムノブロットにより、目的のタンパク質の発現を確認してください。 </li></ol></li></ol> 4.染色および定量<ol><li>クリスタルバイオレット染色<ol><li> NIH 3T3培地を吸引し、食器を置く氷の上で。 </li><li>氷冷PBSで2回皿を洗う。 </li><li> 10分間氷冷メタノールで細胞を固定します。 </li><li>氷から皿を外し、メタノールを吸引し、25％のメタノール（RT）で行われた、0.5％クリスタルバイオレット溶液の3ミリリットルを追加します。 </li><li> RTで5分間皿をインキュベートする。 </li><li>クリスタルバイオレット溶液を吸引し、色がリンスに外れなくなるまで注意深くのMilli-Q H 2 Oとの皿をすすぐ。 </li><li>料理はベンチトップ（発見）にO / Nを乾燥することができます。 </li></ol></li><li>病巣の定量<ol><li>料理が乾燥したら、プレート上の細胞の暗色コレクションを測定するために定規を使用しています。として、直径5ミリメートルよりも大きくされているもののみをカウント &quot;巣&quot;を病巣の数を記録し、対照と比較して平均値と有意性を計算。 </li></ol></li></ol>

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著者らは、開示することは何もない。

FFAは、in vitroでの悪性形質転換を評価するための迅速かつ容易な方法を提供する。これは、候補遺伝子の比較的多数のスクリーニングに適用され、その控えめな技術的要件は、費用対効果を高める。さらに、2つ以上の遺伝子を共発現させることができる組み合わせの腫瘍形成能を評価するために（時には「協力」アッセイと呼ばれる）。このアッセイの利点は、その単純な手法、定量...

腫瘍細胞は、遺伝子発現のパターンの形態学的および増殖性の変化にエピゲノミクスに、変化の広い範囲によってそれらの正常な対応物と区別することができる。後者の中では、、、接触の損失（密度）阻害を血清への依存を軽減足場非依存性増殖の取得と、最終的には、動物に注射した場合に腫瘍を形成する能力は、悪性形質転換3の有効、測定可能な指標である。 in vitroおよびin vivoアッセイにおけるいくつかの細胞の形質転換のために開発されてきた。 インビトロアッセイは、（成長速度、飽和密度）及び増殖因子（低血清成長）、培養形態（フォーカス形成アッセイ）の変化を識別し、測定時に培養ダイナミクスを目指すまたは要件アンカレッジ（ソフトアガーでの成長）。細胞型の悪性の性質を決定するためのゴールドスタンダードは、実験動物における腫瘍形成（異種移​​植片）のままである。しかし、T彼は、コストとのインビボ研究の長さは、常に候補癌遺伝子の最初の検証ステップまたはスクリーニング、それらに正当ことはありません。何のin vitroアッセイは、遺伝子の発癌性の明確な評価を提供していないが、これらは、生体内の研究で未来を絞り込むことが発癌性への洞察を提供します。 インビトロでの発癌性を評価するための最も広く使用されているシステムの一つはフォーカス形成アッセイ2である。このアプローチは、NIH 3T3マウス線維芽細胞、強く接触阻害を示し、非形質転換細胞株の使用に依存している。密度依存性増殖の損失の癌遺伝子の過剰発現。形質転換された細胞は、次に簡単に非形質転換細胞のバックグラウンド単層に対して可視化「病巣」を形成する、複数の層で成長することができる。フォーカス形成アッセイは、その後、コンタクトInhibが喪失によって証明されるように、悪性形質転換を誘導する候補癌遺伝子の能力を測定する測定可能な表現型としてition。 FFAは、プロテインキナーゼ（ 例えば 、Srcの4、BRAF 5）の過剰発現により形質転換を評価するために使用されている、転写因子（ 例えば 、N-mycの6）、Gタンパク質共役受容体（ 例えば 、P2RY8 7）およびGTPアーゼ（ 例えばとりわけラス1）。このアッセイの相対的な容易さは、遺伝子の過剰発現は、インビトロで NIH 3T3マウス線維芽細胞を形質転換するのに十分であるか否かを迅速かつ視覚的に明確な答えを提供する適切な選択肢となる。 FFAは、このプロトコルに記載のレトロウイルスを産生するウイルスパッケージングタンパク質を提供するのPlat-Eパッケージング細胞株8、およびレトロウイルスベクターpBABEpuro 9（Addgeneプラスミド1764）を使用する。目的の遺伝子を含むpBABEpuro構築物でトランスフェクションした後、のPlat-E細胞株は、NIH 3T3細胞を感染させるために使用することができるエコトロピックレトロウイルスを産生する。 T遺伝子送達の彼のウイルスの方法は、従来の化学的なトランスフェクション法よりも効率的であり、それは持続的に遺伝子10を表現する方法を提供しています。 NIH 3T3細胞のゲノムに組み込まれると、目的の遺伝子の過剰発現は、ウイルスの長い末端反復（LTR）プロモーター11によって駆動される。この定数式は、NIH 3T3細胞に、病巣の形成によって測定されるように、目的の遺伝子は、発癌活性を有するかどうかを決定するために使用することができる。

<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は、MYC / MAX / MADネットワークのメンバーである塩基性ヘリックス - ループ - ヘリックスロイシンジッパー（bHLHZ）転写因子である。それは、MADファミリー13-15の異型メンバーであり、発癌16,17に関与することが報告されている。 pBABEpuro（陰性対照）およびMYC（陽性対照）と比較した場合、MXD3を過剰発現させたNIH 3T3料理が著しく少ない病巣（ 図1A）を有してい?...

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

フォーカス形成アッセイは、候補癌遺伝子の形質転換能を評価するための簡単​​な方法を提供する。

フォーカス形成：細胞ベースのアッセイ遺伝子の発癌性を決定するために、

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 ビュー.  University of California, Davis. フォーカス形成アッセイは、候補癌遺伝子の形質転換能を評価するための簡単​​な方法を提供する。 

ビデオ: 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.

PTSDの、ニューラル血液学的および行動的相関関係を明らかにするための動物モデルにおけるバイオマーカー

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

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.

胎児のマウスモデルにおける生物活性剤の気管内投与のための新しい手術アプローチ

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.

ハイスループットフローサイトメトリー細胞ベースのアッセイN-メチル-D-アスパラギン酸受容体またはヒト血清中のドーパ​​ミン-2受容体に対する抗体を検出する

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.

変更された<em&gt;インビトロ</em媒介する癌細胞浸潤におけるホルモン、サイトカインおよび/または成長因子の潜在的な役割を決定するために&gt;浸潤アッセイ

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.

小説<em&gt; in vivoで</em&gt;遺伝子導入技術と<em&gt; in vitroで</em筋骨格障害における骨損失の検討のための&gt;細胞ベースのアッセイ

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.

三次元（3D）腫瘍スフェロイド浸潤アッセイ

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.

乳癌細胞における腫瘍形成の阻害剤を同定するための軟寒天コロニー形成アッセイの活用

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遺伝子サイレンシング：潜在的ながん治療薬の七量体型スモールガイドRNAライブラリーのスクリーニング

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.

同系マウスメラノーマ細胞の注入は、肺におけるそれらの転移能を決定するために、

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.

ヒトの血液脳脊髄液関門の脈絡叢上皮細胞ベースのモデルは、基底外側からの細菌感染症を研究するために、

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