The authors would like to acknowledge the Netherlands Organization for Scientific Research (NWO, grant 17.106.329)

Experimentos em animais foram aprovados pelo comitê de bem-estar dos animais do Centro Médico da Universidade de Leiden (LUMC). 1. Preparação de células, instrumentos e Ratos <ol><li> Um dia antes da operação, raspar a / SCID gamma (NSG) camundongos NOD a partir do quarto mamilo até a linha média e pesar os ratinhos para verificar se todos os ratos têm pesos mais ou menos comparáveis. </li><li> Autoclave uma tesoura, duas pinças e duas pinças de mosquito retas (Figura 1A). </li><li> No dia da operação, lavar o adenocarcinoma da mama humano (MDA-MB-231), as células que irão ser injectados uma vez com solução salina tamponada com fosfato (PBS), pH 7,4 e as células trypsinize. Extingue-se a tripsina por adição de 10 mL contendo soro de meio DMEM por cima das células. Centrifuga-se as células a 1.200 rpm durante 7 minutos à temperatura ambiente para remover o soro por ressuspensão das células quer em PBS ou em meios sem soro. Centrifuga-se de novo para remover vestígios de soro completamente. Ressuspender as células em PBS oumídia. </li><li> Contar as células com um hemocitómetro e calcular a quantidade de células. Use 500.000 células / rato em não mais de 150 mL. Facultativo à PBS ou mídia, voltar a suspender as células em matrigel. NOTA: Determinar a quantidade de células, dependendo do tipo de células utilizado. </li><li> Coloque as células em uma estéreis microtubos e mantê-los no gelo. </li><li> Encher um tubo de centrífuga de 50 mL cónico com 35 ml de PBS pH 7,4 e um outro tubo de centrífuga cónico de 50 mL com etanol a 70%. Mergulhe cotonetes para cada tubo. </li></ol> 2. Injecção ortotópico <ol><li> Realizar a cirurgia num hote estéril para manter um ambiente estéril. Anestesiar o rato por injecção subcutânea mistura xilazina / cetamina na dose de 10 mg / kg, 100 mg / kg de peso corporal, respectivamente. Corrigir o mouse sobre uma almofada de aquecimento. Confirme o sucesso da anestesia com a falta de reação aos pés pinch. NOTA: Se a pessoa não está muito familiarizado com os procedimentos cirúrgicos, a cirurgia pode demorar mais tempo. Organizaras doses de acordo com a anestesia. </li><li> Aplicar pomada oftálmica nos olhos de ratos, para evitar que os olhos sequem. </li><li> Limpe a área raspada, usando o cotonete embebido em álcool preparado no passo 1.6. Alternando esfrega usando betadine e álcool três vezes em uma forma circular rotativo para longe do local da incisão prevista deve ser realizada. Alternativamente, usar ionóforo como um desinfectante. </li><li> Faça uma pequena incisão entre o quarto mamilo e da linha média com uma tesoura e fazer um bolso, inserindo o cotonete umedecido com PBS pH 7,4. </li><li> Utilize uma pinça para expor a almofada de gordura mamaria. Observe a almofada de gordura por sua cor branca. </li><li> Aperte a almofada de gordura com a outra pinça de sua base; ao fazer isso, expor totalmente a almofada de gordura (Figura 1B) para realizar injecções facilmente. </li><li> Homogeneizar a mistura de células por pipetagem cima e para baixo. Suavemente aspirar 50 ul de suspensão de células para uma seringa de insulina e injectara almofada de gordura mamaria, mantendo a agulha horizontalmente. Confirme injeção bem-sucedida verificando para o inchaço da camada de gordura. </li><li> Solte suavemente a almofada de gordura. </li><li> Suturar a incisão utilizando um controlador de agulha. Faça três lances girando a sutura ao redor do motorista agulha no sentido horário, anti-horário e sentido horário. Dois nós por a sutura deve ser usado. NOTA: Certifique-se os nós estão apertados em contrário camundongos pode abrir as suturas. </li><li> Após a cirurgia, injectar um analgésico, tal como a Temgesic 0,05-0,1 mg / kg de peso corporal, por via subcutânea, a fim de aliviar a dor. </li><li> Não deixar os animais sozinhos até que ganhem consciência e manter decúbito externo. Coloque todos os animais em gaiolas diferentes, até que sejam totalmente recuperado. </li><li> Para manter a esterilidade, utilize gaiolas autoclavados e água. Altere as gaiolas cada três dias para manter o ambiente limpo. </li></ol> 3. Extraindo Órgãos para Análise <ol><li> Nodia da colheita, 8 semanas após a implantação das células, preencher 15 ml tubos de centrifugação cónicos com 3 ml de solução de Bouin para cada rato. Além disso, usar dois tubos de 15 ml contendo 5 ml de solução de formol por mouse. </li><li> Anestesiar os animais por injecção de xilazina / cetamina, a uma dose de 10 mg / kg 100 mg / kg de peso corporal por via subcutânea. Aguarde até que o animal perde toe retirada pitada reflexo. </li><li> Corrigir o animal com agulhas em uma base. Faça, uma incisão na linha média longo vertical com uma tesoura. Faça duas incisões horizontais logo abaixo da perna da frente e acima da perna de trás. Expor o tumor fixando a pele para a base. Medir o volume do tumor, utilizando um compasso de calibre. </li><li> Dissociar o tumor da pele com uma tesoura. Encaixe congelar uma parte do tumor em azoto líquido para o isolamento de ARN. Coloque a outra parte, para o tubo de centrífuga cónico preenchidos com formol para realizar imunohistoquímica seguinte inclusão em parafina. </li><li> Gentilmente tirar os pulmões. Coloque apulmão esquerdo em solução de Bouin. Manter o pulmão em solução durante 3 dias. Observe focos metastáticos superficial claramente a olho nu. Opcionalmente, coloque o pulmão direito em formol para verificar micrometastasis usando hematoxilina e eosina (H &amp; E) coloração. NOTA: Embora, metástase pulmonar observado com freqüência em câncer de mama, a pessoa também pode querer recolher ossos, fígado, cérebro e do baço para analisar metástase. As células na área metastático são mais densas e morfologicamente diferentes e, portanto, pode ser facilmente distinguida do tecido do pulmão. </li><li> Um dia após a colheita, aspirar a solução de formol a partir de tubos de 15 ml e substituir com etanol 70%. Incorporar os tecidos em parafina e realizar estudos de imuno-histoquímica. </li><li> Para a análise de sangue, abrir a cavidade torácica com uma tesoura. Retirar 450 sangue ul via punção cardíaca. Coloque amostra de sangue num tubo de microcentrífuga contendo 50 ul de citrato de sódio a 3,2%. Após coletar o sangue, girá-lo a 2.000 xg por 10 min. Armazenar as amostras de plasma a -20 ° C até à sua utilização. NOTA: Existem várias outras técnicas de coleta de sangue geralmente utilizados na prática de 20 ea técnica que precisa ser usado depende de configuração experimental e escolha do cientista. Se a amostra de sangue não é necessário, sacrificar o animal de acordo com o protocolo do animal ou de acordo com as orientações da instituição. </li></ol>

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The authors declare that they have no competing financial interests.

Orthotopic injeção de células de câncer de mama é um modelo poderoso para estudar todos os aspectos do crescimento do câncer. A implantação destas células na almofada de gordura mamaria de ratinhos deve ser realizada cuidadosamente, de modo a evitar variações no crescimento do tumor. Mais importante ainda, injectando a mesma quantidade de células para cada ratinho é crucial. Para fazê-lo, deve-se trypsinize rigorosamente as células sem afectar a viabilidade das células. As células não viáveis ​​de...

O câncer é uma doença muito complexa, que tem sido objeto de estudos há mais de séculos. O câncer de mama é o tipo de câncer mais comum; ela ocorre predominantemente em mulheres, mas esporadicamente também pode ocorrer em homens 27. A doença é provocada, principalmente, pela perda de divisão celular governar mecanismo de controlo que por sua vez leva a um crescimento infinito de células no corpo. Estas avarias podem ser causados ​​por vários mecanismos: primeiro, as células saudáveis ​​necessitam de sinais de crescimento das células vizinhas, de modo a proliferar enquanto que as células do cancro tornam os seus próprios factores de crescimento e aumentar a expressão de receptores do factor de crescimento obtendo-se assim uma taxa de proliferação mais elevada 1; segundo, as células cancerosas são menos suscetíveis aos sinais anti-proliferativa 8; em terceiro lugar, para equilibrar o número de células no processo de morte celular do corpo é também necessário; no entanto, as células cancerosas escapar da morte celular programada, designada apoptose 14; em quarto lugar, as células aderem à matriz extracelulara fim de sobreviver, mas as células tumorais podem crescer sem a necessidade de fixação e apresentam resistência a anoikis 19; em quinto lugar, a activação da telomerase contorna o encurtamento dos telómeros e evita a senescência replicativa 21; por último, mas não menos importante, saltando de DNA controle de qualidade após os resultados de mitose no conteúdo genético alterado 15,16. A fim de identificar os oncogenes ou supressores de tumor, que desempenham um papel neste proliferação desregulada, experiências de crescimento tumoral em ratinhos são cruciais. Crescimento do tumor primário geralmente não é o principal motivo da morte. A migração de células de cancro do local primário para um local secundário, denominado metástase, é a principal causa de morte na maioria dos doentes com cancro 22. Metástase implica invasão das células tumorais, intravasation, viajando através da circulação, evitando ataque imunológico, o extravasamento e crescimento no site secundário. Epitelial para mesenquimal (EMT) é um processo chave nametástase e envolve uma mudança no perfil de expressão produzindo células com maior mobilidade e capacidade de invasão, que são pré-requisitos para a célula metastasizing 12. Como o processo canceroso é o resultante de uma combinação de várias acções, incluindo as interacções recíprocas entre as células cancerosas, células estromais e células pró e anti-inflamatórios, uma abordagem in vitro para o cancro, muitas vezes não fornecer uma visão completa do o processo cancerígeno. Da mesma forma, os tratamentos anti-cancerígenos que afectam a vasculatura do tumor muitas vezes não pode ser estudado in vitro, assim, a utilização de abordagens in vivo é inevitável. Para estudar a progressão do câncer de mama, foram desenvolvidos diferentes métodos experimentais. O modelo mais largamente utilizado é a injecção subcutânea de células de cancro da mama em ratinhos 5. Nesta montagem experimental, o investigador pode apresentar uma ampla gama de alterações a uma linha celular de escolha in vitro (isto é,supra-regulação, a regulação negativa de proteínas) e injectar as células sob a pele. Embora este método seja simples e o processo de injecção é simples, sem qualquer necessidade de se realizar a cirurgia em ratos, o local em que o tumor é injectado não representa o ambiente do tumor mamário local e a ausência desse ambiente pode resultar no desenvolvimento de cancro da mama que difere da observada em patologia humana. Em segundo lugar, ratos geneticamente modificados são usados ​​com freqüência como uma ferramenta in vivo para estudar a progressão do câncer de mama. Neste modelo, oncogene (ou seja, PyMT, Neu) a expressão é conduzida por um promotor específico de tecido mamário que conduz à formação espontânea de tumores da mama s. Esta configuração experimental é útil para estudar o aspecto do tratamento da doença pelo uso de drogas injetáveis ​​ou anticorpos ao verificar o tamanho do tumor em tempo 3. No entanto, a criação destes ratos com outras linhagens de camundongos deficientes ou mutantes em um gene de interesse pode também dar-insights para o papel de proteínas diferentes no crescimento do tumor da mama 24. A desvantagem deste modelo é que ele está propenso a variação no tamanho do tumor e número. Além disso, o nível de expressão do transgene depende do local de integração no genoma e pode mudar de uma estirpe de ratinho para outro 4. Neste modelo, a expressão do transgene pode ser conseguida por todas as células com origem epitelial enquanto que na doença humana, só uma subpopulação de células expressam o oncogene ou infra-regular os níveis de supressão tumoral 26. Para estudar a metástase, células de cancro da mama também pode ser injectado por via intravenosa (um modelo denominado metástase experimental) 25. No entanto, esta abordagem apenas recapitula o processo metastático parcialmente; isto evita a necessidade de células tumorais para invadir e intravasate, e começa a partir do ponto em que as células tumorais são prontamente presentes na circulação. Em nosso trabalho, nós usamos uma injeção orthotopicion modelo para estudar o envolvimento de genes de interesse na progressão do cancro da mama 13. Nós overexpress a proteína em células de câncer de mama humano e injecta-se na almofada de gordura mamária de NOD / SCID gamma (NSG) camundongos. Este método é vantajoso em muitos aspectos: ela permite que as mudanças genéticas muito rápidos e diversificados na linha de células injetadas, que abrange todo o processo de progressão do cancro da mama de crescimento do tumor primário à metástase em locais patologicamente relevantes, e também fornece um bom modelo experimental para estudar o impacto de tratamentos terapêuticos em estágios precoces ou tardias da doença. Além disso, a utilização deste modelo pode-se investigar o papel do estroma contra proteínas derivadas de células de cancro na progressão da doença, utilizando ratos ou células geneticamente modificadas. Embora injecções subcutâneas são mais fáceis de executar, os modelos ortotópicos dar origem a uma população de células de cancro mais tumorigénico e mais metastático. Assim, os resultados obtidos por meio da injecção subcutâneas pode ser falso-negativos ou falso-positivo 6,17 incentivando o uso de modelos ortotópicos para estudar o crescimento do tumor.

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			<td height="17" style="height:17px;width:185px;">Name of material/equipment</td>
			<td style="width:172px;">Company</td>
			<td style="width:95px;">Catalog number</td>
			<td style="width:641px;">Comments/Description</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Bouin&#39;s solution</td>
			<td>Sigma-Aldrich</td>
			<td>HT10132</td>
			<td>Used for investigating the metastasis on lungs</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Formalin solution</td>
			<td>Sigma-Aldrich</td>
			<td>HT501128</td>
			<td>Used to fix the tissues</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Matrigel, growth factor reduced</td>
			<td>Corning</td>
			<td>356230</td>
			<td>Cells can be resuspended in matrigel for injection</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Mosquito forceps</td>
			<td>Fine Science Tools</td>
			<td>13008-12</td>
			<td>Used for stiching</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Angled forceps</td>
			<td>Electron microscopy sciences</td>
			<td>72991-4c</td>
			<td>These make the exposure of mammary fat pad easier</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Scissors</td>
			<td>B Braun Medicals</td>
			<td>BC056R</td>
			<td>Used to cut open the mice</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Straight forceps</td>
			<td>B Braun Medicals</td>
			<td>BD025R</td>
			<td>This is used to open up the skin to expose mammary fat pad</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">NOD scid gamma mice</td>
			<td>Charles River</td>
			<td>005557</td>
			<td>Experimental animal used for experiment</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">MDA-MB-231</td>
			<td>Sigma-Aldrich</td>
			<td>92020424</td>
			<td>Experimental cells used for injections</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Oculentum simplex</td>
			<td>Teva Pharmachemie</td>
			<td></td>
			<td>Opthalmic ointment used to prevent drying out of eyes</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Betadine</td>
			<td>Fischer Scientific</td>
			<td>19-898-859</td>
			<td>Ionophore, used to disinfect the surgical area</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Xylazin/Ketamine</td>
			<td>Sigma-Aldrich</td>
			<td>X1251, K2753</td>
			<td>Use injected anesthesia as 10mg/kg and 100mg/kg body weight respectively</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Temgesic</td>
			<td>Schering-Plough</td>
			<td></td>
			<td>Use the painkiller as 0,05-0,1mg/kg body weight</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">DMEM</td>
			<td>Life sciences</td>
			<td>11995</td>
			<td>For trypsin neutralization,use media with serum(FBS:media 1:10 volume); for injection, use media with no serum</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Buffered sodium citrate</td>
			<td>Aniara</td>
			<td>A12-8480-10</td>
			<td>Use the volume ratio as citrate:blood; 1:9</td>
		</tr>
	</tbody>
</table>

orthotopic injection of breast cancer cells into the mammary fat pad of mice to study tumor growth.

<html> O crescimento do câncer de mama pode ser estudado em ratos usando uma infinidade de modelos. A manipulação genética de células de câncer de mama podem fornecer insights sobre as funções das proteínas envolvidas na progressão oncogênico ou ajuda a descobrir novas supressores de tumor. Além disso, a injecção de células cancerosas em ratos com diferentes genótipos podem proporcionar uma melhor compreensão sobre a importância do compartimento estromal. Muitos modelos pode ser útil para investigar certos aspectos da progressão da doença, mas não recapitular todo o processo cancerígeno. Em contraste, células de cancro da mama enxerto para a almofada de gordura mamaria de ratinhos melhores recapitula o local da doença e na presença do compartimento estromal adequada e, portanto, melhores imita doença cancerosa humana. Neste artigo, nós descrevemos como implantar células de câncer de mama em ratos ortotopicamente e explicar como coletar tecidos para analisar o: 14px; line-height:. 28px; &quot;&gt; meio de tumores e metástases para órgãos distantes Usando esse modelo, muitos aspectos (crescimento, angiogênese e metástase), de câncer pode ser investigado simplesmente fornecendo um ambiente adequado para as células tumorais a crescer.

A aplicação bem sucedida do &quot;modelo ortotópico de cancro da mama&quot; é baseado na injecção de células adequada na almofada de gordura mamaria. Erros experimentais, tais como a inoculação de células imprecisa ou vazamento pode conduzir a variações no tamanho do tumor ou mesmo a ausência de um tumor o que leva à formação de uma estrutura semelhante à procura de uma almofada de gordura mamária injectado com um tampão de controlo (Figura 2A). A taxa de crescimento do tumor é depen...

Watch this Scientific Journal Video about Orthotopic Injection of Breast Cancer Cells into the Mammary Fat Pad of Mice to Study Tumor Growth. at JoVE.com

Orthotopic Injection of Breast Cancer Cells into the Mammary Fat Pad of Mice to Study Tumor Growth.

O cancro é uma doença complexa que é influenciada pelo tecido circundante do tumor, bem como pro- local e anti-inflamatórias mediadores. Portanto, os modelos de injeção ortotrópicas, ao invés de modelos subcutâneos pode ser útil para estudar a progressão do câncer de uma forma que melhor mimetiza patologia humana.

Injeção Orthotopic de células cancerosas da mama na mamária Fat Pad de Ratos para o Estudo de crescimento tumoral.

Breast cancer growth can be studied in mice using a plethora of models. Genetic manipulation of breast cancer cells may provide insights into the ...

orthotopic-injection-breast-cancer-cells-into-mammary-fat-pad-mice-to

Research

JoVE Journal

Medicine

78.3K visualizações.  Leiden University Medical Center.  O cancro é uma doença complexa que é influenciada pelo tecido circundante do tumor, bem como pro- local e anti-inflamatórias mediadores. Portanto, os modelos de injeção ortotrópicas, ao invés de modelos subcutâneos pode ser útil para estudar a progressão do câncer de uma forma que melhor mimetiza patologia humana. 

Vídeo: Orthotopic Injection of Breast Cancer Cells into the Mammary Fat Pad of Mice to Study Tumor Growth.

Performing and Processing FNA of Anterior Fat Pad for Amyloid

Historically, heart, liver, and kidney biopsies were performed to demonstrate amyloid deposits in amyloidosis. Since the clinical presentation of this disease is so variable and non-specific, the associated risks of these biopsies are too great for the diagnostic yield. Other sites that have a lower biopsy risk, such as skin or gingival, are also relatively invasive and expensive. In addition, these biopsies may not always have sufficient amyloid deposits to establish a diagnosis. Fat pad aspiration has demonstrated good clinical correlation with low cost and minimal morbidity. However, there are no standardized protocols for performing this procedure or processing the aspirated specimen, which leads to variable and nonreproducible results. The most frequently utilized modality for detecting amyloid in tissue is an apple-green birefringence on Congo red stained sections using a polarizing microscope. This technique requires cell block preparation of aspirated material. Unfortunately, patients presenting in early stage of amyloidosis have minimal amounts of amyloid which greatly reduces the sensitivity of Congo red stained cell block sections of fat pad aspirates. Therefore, ultrastructural evaluation of fat pad aspirates by electron microscopy should be utilized, given its increased sensitivity for amyloid detection. This article demonstrates a simple and reproducible procedure for performing anterior fat pad aspiration for the detection of amyloid utilizing both Congo red staining of cell block sections and electron microscopy for ultrastructural identification.

Fat pad aspiration is a preferred, minimally invasive, and low cost approach as compared to other methods to detect amyloid for diagnosis of systemic amyloidosis. This video article demonstrates a procedural outline for performing fat pad aspiration with appropriate processing of the specimen for the optimal diagnostic outcome.

Executar e Processamento de FNA Pad Fat Anterior para amilóide

Historically, heart, liver, and kidney biopsies were performed to demonstrate amyloid deposits in amyloidosis.  Since the clinical presentation of this ...

Medicina

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent until many years after removal of the primary tumor and adjuvant therapy. A likely explanation of this phenomenon is that tumor cells have seeded metastatic sites, are resistant to conventional therapies, and remain dormant for long periods of time 1-4.
The existence of dormant cancer cells at secondary sites has been described previously as quiescent solitary cells that neither proliferate nor undergo apoptosis 5-7. Moreover, these solitary cells has been shown to disseminate from the primary tumor at an early stage of disease progression 8-10 and reside growth-arrested in the patients' bone marrow, blood and lymph nodes 1,4,11. Therefore, understanding mechanisms that regulate dormancy or the switch to a proliferative state is critical for discovering novel targets and interventions to prevent disease recurrence. However, unraveling the mechanisms regulating the switch from tumor dormancy to metastatic growth has been hampered by the lack of available model systems.
in vivo and ex vivo model systems to study metastatic progression of tumor cells have been described previously 1,12-14. However these model systems have not provided in real time and in a high throughput manner mechanistic insights into what triggers the emergence of solitary dormant tumor cells to proliferate as metastatic disease. We have recently developed a 3D in vitro system to model the in vivo growth characteristics of cells that exhibit either dormant (D2.OR, MCF7, K7M2-AS.46) or proliferative (D2A1, MDA-MB-231, K7M2) metastatic behavior in vivo . We demonstrated that tumor cells that exhibit dormancy in vivo at a metastatic site remain quiescent when cultured in a 3-dimension (3D) basement membrane extract (BME), whereas cells highly metastatic in vivo readily proliferate in 3D culture after variable, but relatively short periods of quiescence. Importantly by utilizing the 3D in vitro model system we demonstrated for the first time that the ECM composition plays an important role in regulating whether dormant tumor cells will switch to a proliferative state and have confirmed this in in vivo studies15-17. Hence, the model system described in this report provides an in vitro method to model tumor dormancy and study the transition to proliferative growth induced by the microenvironment.

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

A modified 3-D in vitro system is presented in which growth characteristics of several tumor cell lines in reconstituted basement membrane correlate with the dormant or proliferative behavior of the tumor cells at a metastatic secondary site in vivo.

Um In Vitro Sistema para Estudo de dormência Tumor ea Mude para o crescimento metastático

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent ...

An Orthotopic Bladder Tumor Model and the Evaluation of Intravesical saRNA Treatment

We present a novel method for treating bladder cancer with intravesically delivered small activating RNA (saRNA) in an orthotopic xenograft mouse bladder tumor model. The mouse model is established by urethral catheterization under inhaled general anesthetic. Chemical burn is then introduced to the bladder mucosa using intravesical silver nitrate solution to disrupt the bladder glycosaminoglycan layer and allows cells to attach. Following several washes with sterile water, human bladder cancer KU-7-luc2-GFP cells are instilled through the catheter into the bladder to dwell for 2 hours. Subsequent growth of bladder tumors is confirmed and monitored by in vivo bladder ultrasound and bioluminescent imaging. The tumors are then treated intravesically with saRNA formulated in lipid nanoparticles (LNPs). Tumor growth is monitored with ultrasound and bioluminescence. All steps of this procedure are demonstrated in the accompanying video.

Establishing an orthotopic bladder tumor model to evaluate antitumor effects of intravesically delivered saRNA and monitoring tumor growth by ultrasound and bioluminescent imaging.

Um modelo de tumor de bexiga ortotópico e Avaliação de Tratamento de sarna intravesical

We present a novel method for treating bladder cancer with intravesically delivered small activating RNA (saRNA) in an orthotopic xenograft mouse bladder ...

Human Neuroendocrine Tumor Cell Lines as a Three-Dimensional Model for the Study of Human Neuroendocrine Tumor Therapy

Neuroendocrine tumors (NETs) are rare tumors, with an incidence of two per 100,&#x200A;000 individuals per year, and they account for 0.5% of all human malignancies.1 Other than surgery for the minority of patients who present with localized disease, there is little or no survival benefit of systemic therapy. Therefore, there is a great need to better understand the biology of NETs, and in particular define new therapeutic targets for patients with nonresectable or metastatic neuroendocrine tumors. 3D cell culture is becoming a popular method for drug screening due to its relevance in modeling the in vivo tumor tissue organization and microenvironment.2,3 The 3D multicellular spheroids could provide valuable information in a more timely and less expensive manner than directly proceeding from 2D cell culture experiments to animal (murine) models.
To facilitate the discovery of new therapeutics for NET patients, we have developed an in vitro 3D multicellular spheroids model using the human NET cell lines. The NET cells are plated in a non-adhesive agarose-coated 24-well plate and incubated under physiological conditions (5% CO2, 37 &deg;C) with a very slow agitation for 16-24 hr after plating. The cells form multicellular spheroids starting on the 3rd or 4th day. The spheroids become more spherical by the 6th day, at which point the drug treatments are initiated. The efficacy of the drug treatments on the NET spheroids is monitored based on the morphology, shape and size of the spheroids with a phase-contrast light microscope. The size of the spheroids is estimated automatically using a custom-developed MATLAB program based on an active contour algorithm. Further, we demonstrate a simple method to process the HistoGel embedding on these 3D spheroids, allowing the use of standard histological and immunohistochemical techniques. 
This is the first report on generating 3D spheroids using NET cell lines to examine the effect of therapeutic drugs. We have also performed histology on these 3D spheroids, and displayed an example of a single drug's effect on growth and proliferation of the NET spheroids. Our results support that the NET spheroids are valuable for further studies of NET biology and drug development.

We present a simple agarose overlay platform to grow 3D multicellular spheroids using neuroendocrine cancer cell lines. This method provides a very convenient way to examine the effect of therapeutic drugs on the neuroendocrine tumor cells. It could also help us establish human neuroendocrine tumor spheroids for cancer therapy.

Humanos Linhas tumor neuroendócrino de células como um modelo tridimensional para o estudo da terapia de tumores humanos Neuroendócrino

Neuroendocrine tumors (NETs) are rare tumors, with an incidence of two per 100,&#x200A;000 individuals per year, and they account for 0.5% of all human ...

Orthotopic Aortic Transplantation in Mice for the Study of Vascular Disease

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. This is largely true, but there are a number of important principles that can reduce the difficulty of these procedures and enhance reproducibility. Orthotopic aortic transplantation is an excellent procedure in which to learn these principles because it involves only two end-to-end anastomoses, but requires good suturing technique and handling of the vessels for consistent success. This procedure begins with the procurement of a length of abdominal aorta from a donor animal, followed by division of the native aorta in the recipient. The procured aorta is then placed between the divided ends of the recipient aorta and sutured into place using end-to-end anastomoses. To accomplish this objective successfully requires a high degree of concentration, good tools, a steady hand, and an appreciation of how easily the vasculature of a mouse can be damaged, resulting in thrombosis. Learning these important principles is what occupies most of the beginner's time when learning microsurgery in small rodents. Throughout this protocol, we refer to these important points. This model can be used to study vascular disease in a variety of different experimental systems1-8. In the context shown here, it is most often used for the study of post-transplant vascular disease, a common long-term complication of solid organ transplantation in which intimal hyperplasia occurs within the allograft. The primary advantage of the model is that it facilitates quantitative morphometric analyses and the transplanted vessel lies contiguous to the endogenous vessel, which can serve as an additional control9. The technique shown here is most often used for mice weighing 18-25 grams. We have accumulated most of our experience using the C57BL/6J, BALB/cJ, and C3H/HeJ strains.

We describe a technique in which a section of the abdominal aorta from a mouse is transplanted orthotopically to just below the renal arteries in an allogeneic or syngeneic recipient. This technique can be useful in studies in which transplantation of large arteries of uniform size is deemed advantageous.

Transplante ortotópico de aorta em camundongos para o Estudo da Doença Vascular

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. ...

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a novel platform that allows for direct long-term visualization of tissue structure changes intracranially. Imaging at a single cell resolution in a real-time fashion provides supplementary dynamic information beyond that provided by standard end-point histological analysis, which looks solely at 'snap-shot' cross sections of tissue.
Establishing this intravital imaging technique in fluorescent chimeric mice, we are able to image four fluorescent channels simultaneously. By incorporating fluorescently labeled cells, such as GFP+ bone marrow, it is possible to track the fate of these cells studying their long-term migration, integration and differentiation within tissue. Further integration of a secondary reporter cell, such as an mCherry glioma tumor line, allows for characterization of cell:cell interactions. Structural changes in the tissue microenvironment can be highlighted through the addition of intra-vital dyes and antibodies, for example CD31 tagged antibodies and Dextran molecules.
Moreover, we describe the combination of our ICW imaging model with a small animal micro-irradiator that provides stereotactic irradiation, creating a platform through which the dynamic tissue changes that occur following the administration of ionizing irradiation can be assessed.
Current limitations of our model include penetrance of the microscope, which is limited to a depth of up to 900 &mu;m from the sub cortical surface, limiting imaging to the dorsal axis of the brain. The presence of the skull bone makes the ICW a more challenging technical procedure, compared to the more established and utilized chamber models currently used to study mammary tissue and fat pads 5-7. In addition, the ICW provides many challenges when optimizing the imaging.

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We describe a novel in vivo imaging technique that couples fluorescent chimeric mice with intracranial windows and high-resolution 2-photon microscopy. This imaging platform aids studies of dynamic changes in brain tissue and microvasculature, at a single-cell level, following pathological insults and is adaptable to assess intracranial drug delivery and distribution.

A Novel de alta resolução<em&gt; In vivo</em&gt; Técnica de Imagem para estudar a resposta dinâmica de estruturas intracranianas ao crescimento do tumor e Terapêutica

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a ...

Three Dimensional Cultures: A Tool To Study Normal Acinar Architecture vs. Malignant Transformation Of Breast Cells

Invasive breast carcinomas are a group of malignant epithelial tumors characterized by the invasion of adjacent tissues and propensity to metastasize. The interplay of signals between cancer cells and their microenvironment exerts a powerful influence on breast cancer growth and biological behavior1. However, most of these signals from the extracellular matrix are lost or their relevance is understudied when cells are grown in two dimensional culture (2D) as a monolayer. In recent years, three dimensional (3D) culture on a reconstituted basement membrane has emerged as a method of choice to recapitulate the tissue architecture of benign and malignant breast cells. Cells grown in 3D retain the important cues from the extracellular matrix and provide a physiologically relevant ex&#160;vivo system2,3. Of note, there is growing evidence suggesting that cells behave differently when grown in 3D as compared to 2D4. 3D culture can be effectively used as a means to differentiate the malignant phenotype from the benign breast phenotype and for underpinning the cellular and molecular signaling involved3. One of the distinguishing characteristics of benign epithelial cells is that they are polarized so that the apical cytoplasm is towards the lumen and the basal cytoplasm rests on the basement membrane. This apico-basal polarity is lost in invasive breast carcinomas, which are characterized by cellular disorganization and formation of anastomosing and branching tubules that haphazardly infiltrates the surrounding stroma. These histopathological differences between benign gland and invasive carcinoma can be reproduced in 3D6,7. Using the appropriate read-outs like the quantitation of single round acinar structures, or differential expression of validated molecular markers for cell proliferation, polarity and apoptosis in combination with other molecular and cell biology techniques, 3D culture can provide an important tool to better understand the cellular changes during malignant transformation and for delineating the responsible signaling.

Three dimensional culture of mammary epithelial cells on a reconstituted basement membrane is a useful method to recapitulate the in vivo architecture of the benign breast, and to differentiate the malignant phenotype from the benign breast phenotype. Importantly, this system can be applied to study invasive carcinomas in other tissues.

Três Culturas dimensionais: Uma ferramenta para o estudo normal Acináceo Arquitetura vs transformação maligna das células de mama

Invasive breast carcinomas are a group of malignant epithelial tumors characterized by the invasion of adjacent tissues and propensity to metastasize. The ...

Tracking the Mammary Architectural Features and Detecting Breast Cancer with Magnetic Resonance Diffusion Tensor Imaging

Breast cancer is the most common cause of cancer among women worldwide. Early detection of breast cancer has a critical role in improving the quality of life and survival of breast cancer patients. In this paper a new approach for the detection of breast cancer is described, based on tracking the mammary architectural elements using diffusion tensor imaging (DTI). 
The paper focuses on the scanning protocols and image processing algorithms and software that were designed to fit the diffusion properties of the mammary fibroglandular tissue and its changes during malignant transformation. The final output yields pixel by pixel vector maps that track the architecture of the entire mammary ductal glandular trees and parametric maps of the diffusion tensor coefficients and anisotropy indices. 
The efficiency of the method to detect breast cancer was tested by scanning women volunteers including 68 patients with breast cancer confirmed by histopathology findings. Regions with cancer cells exhibited a marked reduction in the diffusion coefficients and in the maximal anisotropy index as compared to the normal breast tissue, providing an intrinsic contrast for delineating the boundaries of malignant growth. Overall, the sensitivity of the DTI parameters to detect breast cancer was found to be high, particularly in dense breasts, and comparable to the current standard breast MRI method that requires injection of a contrast agent. Thus, this method offers a completely non-invasive, safe and sensitive tool for breast cancer detection.

We describe how to obtain parametric and vector maps of the diffusion tensor of the breast using magnetic resonance imaging. The protocol and final output following imaging processing are tailored for tracking breast architectural features and detecting breast malignancy.

Acompanhando as mamárias elementos arquitectónicos e detecção do câncer de mama com Ressonância Magnética Tensor Difusão de imagens

Breast cancer is the most common cause of cancer among women worldwide. Early detection of breast cancer has a critical role in improving the quality of ...

Assessment of Viability of Human Fat Injection into Nude Mice with Micro-Computed Tomography

Lipotransfer is a vital tool in the surgeon&#8217;s armamentarium for the treatment of soft tissue deficits of throughout the body. Fat is the ideal soft tissue filler as it is readily available, easily obtained, inexpensive, and inherently biocompatible.1 However, despite its burgeoning popularity, fat grafting is hampered by unpredictable results and variable graft survival, with published retention rates ranging anywhere from 10-80%. 1-3
To facilitate investigations on fat grafting, we have therefore developed an animal model that allows for real-time analysis of injected fat volume retention. Briefly, a small cut is made in the scalp of a CD-1 nude mouse and 200-400 &#181;l&#160;of processed lipoaspirate is placed over the skull. The scalp is chosen as the recipient site because of its absence of native subcutaneous fat, and because of the excellent background contrast provided by the calvarium, which aids in the analysis process. Micro-computed tomography (micro-CT) is used to scan the graft at baseline and every two weeks thereafter. The CT images are reconstructed, and an imaging software is used to quantify graft volumes.
Traditionally, techniques to assess fat graft volume have necessitated euthanizing the study animal to provide just a single assessment of graft weight and volume by physical measurement ex vivo. Biochemical and histological comparisons have likewise required the study animal to be euthanized. This described imaging technique offers the advantage of visualizing and objectively quantifying volume at multiple time points after initial grafting without having to sacrifice the study animal. The technique is limited by the size of the graft able to be injected as larger grafts risk skin and fat necrosis. This method has utility for all studies evaluating fat graft viability and volume retention. It is particularly well-suited to providing a visual representation of fat grafts and following changes in volume over time.

Fat grafting is an essential technique for reconstructing soft tissue deficits. However, it remains an unpredictable procedure characterized by variable graft survival. Our goal was to devise a mouse model that utilizes a novel imaging method to compare volume retention between differing techniques of fat graft preparation and delivery.

Avaliação da viabilidade de gordura humana injecção em ratinhos nu com Micro-Tomografia Computadorizada

Lipotransfer is a vital tool in the surgeon&#8217;s armamentarium for the treatment of soft tissue deficits of throughout the body. Fat is the ideal soft ...

An Ex vivo Model to Study Hormone Action in the Human Breast

The study of hormone action in the human breast has been hampered by lack of adequate model systems. Upon in vitro culture, primary mammary epithelial cells tend to lose hormone receptor expression. Widely used hormone receptor positive breast cancer cell lines are of limited relevance to the in vivo situation. Here, we describe an ex vivo model to study hormone action in the human breast. Fresh human breast tissue specimens from surgical discard material such as reduction mammoplasties or mammectomies are mechanically and enzymatically digested to obtain tissue fragments containing ducts and lobules and multiple stromal cell types. These tissue microstructures kept in basal medium without growth factors preserve their intercellular contacts, the tissue architecture, and remain hormone responsive for several days. They are readily processed for RNA and protein extraction, histological analysis or stored in freezing medium. Fluorescence activated cell sorting (FACS) can be used to enrich for specific cell populations. This protocol provides a straightforward, standard approach for translational studies with highly complex, varied human specimens.

An Ex vivo Model to Study Hormone Action in the Human Breast

We have developed a novel ex vivo model to study hormone action in the human breast. It is based on tissue microstructures isolated from surgical breast tissue specimens which preserve tissue architecture, intercellular interactions, and paracrine signaling.

Um<em&gt; Ex vivo</em&gt; Modelo para estudar a ação do hormônio no peito humano

The study of hormone action in the human breast has been hampered by lack of adequate model systems. Upon in vitro culture, primary mammary epithelial ...