The authors would like to thank Safia Zahma for her help with the preparation of tissue sections.

All experimental protocols as outlined below follow ethical guidelines and were approved by the Austrian Federal Ministry of Science, Research and Economy.
NOTE: The protocol here describes an orthotopic transplantation model of mouse lung adenocarcinoma cells into syngeneic recipients. Cells may be isolated from tumor-bearing lungs of KrasLSL-G12D:p53fl/fl (KP) mice7,18, if available in-house, and transplanted into mice of the same background and sex. If cells were provided from other research groups and the exact background remains unknown, we recommend the use of the F1 generation of a cross between C57BL/6 and 129S mice as transplant recipients to guarantee maximal tolerance.
1. Cell Preparation
<ol>
	<li>Seed KP cells 24 h before transplantation at approximately 50% confluency in RPMI supplemented with 10% fetal calf serum (FCS), glutamine, and 100 U/mL penicillin and 100 &#956;g/mL streptomycin (hereafter referred to as standard culture medium). Incubate the cell cultures at 37&#176; C, 5% CO2, and around 95% relative humidity.</li>
	<li>On the next day, harvest cells using 1 mL of trypsin-EDTA (0.05% in phosphate-buffered saline [PBS]) for 5 min per 10 cm plate and, subsequently, resuspend detached cells with 9 mL of standard culture medium.</li>
	<li>Count the cells in a hemocytometer and transfer the number of cells needed for the experiments in a 50-mL conical centrifuge tube. 
	NOTE: We recommend transplanting between 2.5 x 105 and 1 x 106 KP cells per mouse, but this might be adapted based on the researcher&#39;s needs.</li>
	<li>Subsequently, centrifuge the cells for 5 min at 300 x g, aspirate the supernatant, and, using a pipette, resuspend the cells at a density of 2 x 107/mL (for the inhalation of 1 x 106 KP cells per mouse) in serum and antibiotic-free RPMI, supplemented with 0.01 M ethylenediaminetetraacetic acid (EDTA).</li>
	<li>Keep the cells on ice until transplantation.</li>
</ol>
2. Orthotopic Transplantation via Intratracheal Delivery
<ol>
	<li>Sedate a mouse (8 - 12 weeks of age) by a subcutaneous injection of a mixture of ketamine (100 mg/kg of body weight) and xylazine (10 mg/kg of body weight).</li>
	<li>While the anesthesia sets in, prepare the catheter for intubation. Therefore, blunt the needle of a catheter by simply cutting the end with scissors. Afterward, push the catheter completely over the end of the needle.</li>
	<li>Confirm the appropriate level of anesthesia by pedal reflex via firm toe pinching and apply ophthalmic ointment to the eyes.</li>
	<li>Fix the mouse on the intubation platform (Figure 1A) by hooking its upper incisors over a suture and confirm that the chest is vertical underneath the suture.</li>
	<li>Place a fiber optic cable in between the front legs to illuminate the chest (Figure 1B).</li>
	<li>Carefully open the mouth of the mouse and pull out the tongue using disinfected flat forceps. Look for the emission of white light to locate the larynx and visualize the epiglottis and arytenoid cartilages (Figure 1C).</li>
	<li>Once the opening of the trachea is clearly visible, gently slide the catheter into the trachea (Figure 1D). The length of the catheter to be inserted depends on the age and size of the animal, since it should not go below the bifurcation to guarantee an even distribution of the lung adenocarcinoma cells within the lung. Quickly remove the needle from the catheter.</li>
	<li>The proper placement of the catheter in the trachea is indicated by the white light shining through the catheter (Figure 1E). In order to confirm the placement of the catheter in the trachea, attach a 1-mL syringe containing water to the catheter. The water in the syringe will rapidly move up and down in accordance with the breathing (Figure 1F). 
	NOTE: This step can be omitted by experienced researchers.</li>
	<li>Warm up the cell suspension by holding the tube in hand and, subsequently, pipette 50 &#181;L of the suspension containing 1 x 106 cells (the number of cells may be variable) into the center of the catheter hub. The suspension will be aspirated immediately. Subsequently, attach a 1 mL syringe and dispense 300 &#181;L of air to assure a consistent distribution within the lungs.</li>
	<li>Gently remove the catheter, remove the mouse from the intubation platform, and put it on a heat pad until it recovers from the anesthesia.</li>
</ol>
3. Lung Preparation for Flow Cytometry
<ol>
	<li>At the desired experimental endpoint, sedate the mouse by a subcutaneous injection of a mixture of ketamine (100 mg/kg of body weight) and xylazine (10 mg/kg of body weight) and euthanize it by cervical dislocation.</li>
	<li>Soak the carcass in 70% ethanol and secure the mouse on a dissection board using tape.</li>
	<li>Make a ventral midline incision and gently invert the skin to expose the thoracic wall muscles and the abdominal organs. Puncture the diaphragm and cut the ribs with scissors to expose the thoracic cavity.</li>
	<li>Perfuse the lungs 3x with 6 - 8 mL of ice-cold PBS through the right ventricle using a 27 G needle after cutting a small opening in the left ventricle to allow blood to leave. The lungs should be cleared of blood and turn completely white.</li>
	<li>Take out the lungs and mince the lobes into small pieces using scissors. Transfer the lung pieces to a 2 mL microcentrifuge tube and incubate it in 1.5 mL of lung digestion buffer (RPMI, 5% FCS, 150 U/mL collagenase I, and 50 U/mL DNase I).</li>
	<li>Incubate the lung pieces 30 - 60 min at 37 &#176;C and with constant shaking.</li>
	<li>Transfer the lung cell suspension through a 70 &#181;m cell strainer into a 50 mL tube. Clear the strainer with the back of a sterile 10-mL syringe and rinse the strainer with 15 mL of PBS with 2% FCS.</li>
	<li>Centrifuge the cells at 300 x g for 5 min at 4 &#176;C and aspirate the supernatant. Resuspend the cells in 1 mL of ammonium-chloride-potassium (ACK) lysing buffer and incubate them for 5 min at room temperature for the lysis of residual erythrocytes.</li>
	<li>Centrifuge the cells at 300 x g for 5 min at 4 &#176;C and resuspend the cells in 1 mL of PBS with 2% FCS and proceed with the desired staining protocol for flow cytometry23. 
	NOTE: Alternatively, the cells may be resuspended in RPMI containing 30% FCS and 10% DMSO and frozen using a freezing container for later analysis.</li>
</ol>

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The authors have nothing to disclose.

To study lung physiologic and pathologic events in the lung, invasive and non-invasive intratracheal intubation methods for the instillation of various reagents are widely used26,27,28,29,30,31,32. In the cancer field, researchers use the intratracheal (and intranasal) instillation of Cre-re...

Lung cancer is still by far the biggest cancer-related killer in both men and women1. Indeed, according to the American Cancer Society, every year more people die of lung cancer than of breast, prostate, and colon cancer together1. Until recently, the majority of patients suffering from non-small cell lung cancer (NSCLC), which is the most abundant subtype of lung cancer, were treated with platinum-based chemotherapy in a first-line setting, mostly with the addition of angiogenesis inhibitors2. Only a subset of patients harbors oncogenic mutations in the epidermal growth factor receptor (EGFR), in anaplastic lymphoma kinase (ALK), or in ROS1, and can be treated with available targeting drugs3,4. With the advent of immune checkpoint inhibitors, new hope for lung cancer patients has arisen, although until now, only 20&#8211;40% of patients respond to immune therapy5. Hence, further research is required to improve this outcome by fine-tuning immune checkpoint therapy and investigating combinatory treatment options.
To study lung cancer, a vast array of preclinical models are available, including spontaneous models triggered by chemicals and carcinogens and genetically engineered mouse models (GEMM) where autochthonous tumors arise following the conditional activation of oncogenes and/or the inactivation of tumor suppressor genes6,7,8. These models are of particular value to investigate fundamental processes in lung tumor development, but they also require extensive mice breeding, and experiments are time-consuming. Therefore, many studies evaluating potential inhibitors take advantage of subcutaneous (patient-derived) xenograft models where human lung cancer cell lines are subcutaneously injected into immunodeficient mice9.
In these models, the micromilieu of tumors is not represented accordingly; hence, researchers also use orthotopic transplantation models, where tumor cells are injected intravenously, intrabronchially, or directly into the lung parenchyma10,11,12,13,14,15,16,17,18,19,20. Some of these methods are technically challenging, difficult to be reproduced, and require intensive training of the researchers.21 Here we adapted a non-invasive orthotopic, intratracheal transplantation method in immunocompetent mice, where tumors develop within 3-5 weeks and exhibit significant similarities to human tumors, to induce the expression of the T-cell suppressor Programmed death-ligand 1 (PD-L1) on tumor cells.11,12,20 The use of mouse tumor cells derived from GEMM models and syngeneic recipient mice allows proper studying of the tumor microenvironment including immune cells. Furthermore, gene editing tools like CRISPR/Cas9 technology22 can be used in vitro before transplantation which facilitates the investigation of the impact of genetic factors in lung tumorigenesis.

<table><tbody><tr><td>mouse lung adenocarcinoma cell line</td><td></td><td></td><td>isolated in house</td></tr><tr><td>C57Bl/6 mice</td><td></td><td></td><td>F1 of the cross of the two backgrounds may be used (8-12 weeks)</td></tr><tr><td>129S mice</td><td></td><td></td><td></td></tr><tr><td>RPMI 1640 Medium</td><td>Life Technologies</td><td>11544446</td><td></td></tr><tr><td>Fetal Calf Serum</td><td>Life Technologies</td><td>11573397</td><td></td></tr><tr><td>Penicillin/Streptomycin Solution</td><td>Life Technologies</td><td>11548876</td><td></td></tr><tr><td>L-Glutamine</td><td>Life Technologies</td><td>11539876</td><td></td></tr><tr><td>Trypsin, 0.25% (1x) with EDTA</td><td>Life Technologies</td><td>11560626</td><td></td></tr><tr><td>UltraPure 0.5 M EDTA, pH 8.0</td><td>Thermo Fisher Scientific</td><td>15575020</td><td></td></tr><tr><td>Ketasol (100 mg/mL Ketamine)</td><td>Ogris Pharma</td><td>8-00173</td><td></td></tr><tr><td>Xylasol (20 mg/mL Xylazine)</td><td>Ogris Pharma</td><td>8-00178</td><td></td></tr><tr><td>BD Insyste (22 GA 1.00 IN)</td><td>BD</td><td>381223</td><td></td></tr><tr><td>Blunt forceps</td><td>Roboz</td><td>RS8260</td><td></td></tr><tr><td>Leica CLS150 LED</td><td>Leica</td><td>30250004</td><td>Fibre Light Illuminator</td></tr><tr><td>Student Iris Scissors</td><td>Fine Science Tools</td><td>91460-11</td><td></td></tr><tr><td>DNase I (RNase-Free)</td><td>New England Biolabs</td><td>M0303S</td><td></td></tr><tr><td>Collagenase Type I</td><td>Life Technologies</td><td>17100017</td><td></td></tr><tr><td>ACK Lysing Buffer</td><td>Lonza</td><td>10-548E</td><td></td></tr><tr><td>CD274 (PD-L1, B7-H1) Monoclonal Antibody (MIH5), PE-Cyanine7</td><td>eBioscience</td><td>25-5982-82</td><td></td></tr><tr><td>Rat IgG2a kappa Isotype Control, PE-Cyanine7</td><td>eBioscience</td><td>25-4321-82</td><td></td></tr></tbody></table>

orthotopic transplantation of syngeneic lung adenocarcinoma cells to study pd-l1 expression

The use of mouse models is indispensable for studying the pathophysiology of various diseases. With respect to lung cancer, several models are available, including genetically engineered models as well as transplantation models. However, genetically engineered mouse models are time-consuming and expensive, whereas some orthotopic transplantation models are difficult to reproduce. Here, a non-invasive intratracheal delivery method of lung tumor cells as an alternative orthotopic transplantation model is described. The use of mouse lung adenocarcinoma cells and syngeneic graft recipients allows studying tumorigenesis under the presence of a fully active immune system. Furthermore, genetic manipulations of tumor cells before transplantation makes this model an attractive time-saving approach to study the impact of genetic factors on tumor growth and tumor cell gene expression profiles under physiological conditions. Using this model, we show that lung adenocarcinoma cells express increased levels of the T-cell suppressor programmed death-ligand 1 (PD-L1) when grown in their natural environment as compared to cultivation in vitro.

We used the orthotopic transplantation model via intratracheal tumor cell delivery to test whether the tumor microenvironment stimulates PD-L1 expression. Therefore, we isolated mouse lung AC cells from the autochthonous KP model (KP cells), 10 weeks following tumor induction via Cre-recombinase-expressing adenovirus (Ad.Cre) delivery24. Subsequently, we labeled the lung AC cells using a green fluorescent protein (GFP)-expressing lentivirus25</sup...

Watch this Scientific Journal Video about Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression at JoVE.com

Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression

Here we describe a minimally invasive syngeneic orthotopic transplantation model of mouse lung adenocarcinoma cells as a time- and cost-reducing model to study non-small cell lung cancer.

The use of mouse models is indispensable for studying the pathophysiology of various diseases. With respect to lung cancer, several models are available, ...

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JoVE Journal

Cancer Research

16.8K Views.  Medical University of Vienna. De orthotopische transplantatie van muislongadenocarcinoomcellen in syngeneic graft ontvangers maakt het mogelijk om tumorigenese te bestuderen in aanwezigheid van een volledig actief immuunsysteem onder fysiologische omstandigheden. Natuurlijk ontwikkelen de tumoren zich tot een immunocompetentiemuizen en dit is veel fysiologischer dat als je een transplantatie uitvoert bij immunodeficiënte muizen. Genbewerking van de tumorcellen vóór een transplantatie maakt dit model een directe en tijd...

Video: Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to inhibit tumor growth must be performed in a suitable animal model. The type of animal model that is best for this purpose is a topic of intense discussion. Some evidence indicates that preclinical trials examining drug effects on tumors arising in transgenic mice are more predictive of clinical outcome1and so candidate therapeutic agents are often tested in these models. Unfortunately, transgenic models are not available for many tumor types. Further, transgenic models often have other limitations such as concerns as to how well the mouse tumor models its human counterpart, incomplete penetrance of the tumor phenotype and an inability to predict when tumors will develop.
Consequently, many investigators use xenograft models (human tumor cells grafted into immunodeficient mice) for preclinical trials if appropriate transgenic tumor models are not available. Even if transgenic models are available, they are often partnered with xenograft models as the latter facilitate rapid determination of therapeutic ranges. Further, this partnership allows a comparison of the effectiveness of the agent in transgenic tumors and genuine human tumor cells. Historically, xenografting has often been performed by injecting tumor cells subcutaneously (ectopic xenografts). This technique is rapid and reproducible, relatively inexpensive and allows continuous quantitation of tumor growth during the therapeutic period2. However, the subcutaneous space is not the normal microenvironment for most neoplasms and so results obtained with ectopic xenografting can be misleading due to factors such as an absence of organ-specific expression of host tissue and tumor genes. It has thus been strongly recommended that ectopic grafting studies be replaced or complemented by studies in which human tumor cells are grafted into their tissue of origin (orthotopic xenografting)2. Unfortunately, implementation of this recommendation is often thwarted by the fact that orthotopic xenografting methodologies have not yet been developed for many tumor types.
Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that occur sporadically or in association with neurofibromatosis type 13and most commonly arise in the sciatic nerve4. Here we describe a technically straightforward method in which firefly luciferase-tagged human MPNST cells are orthopically xenografted into the sciatic nerve of immunodeficient mice. Our approach to assessing the success of the grafting procedure in individual animals and subsequent non-biased randomization into study groups is also discussed.

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

A method for reliably grafting luciferase-tagged human malignant peripheral nerve sheath tumor cells into the sciatic nerve of immunodeficient mice is described. The use of bioluminescence imaging to demonstrate proper establishment of tumor grafts and criteria for random segregation of animals into study groups are also discussed.

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to ...

Medicine

Immunophenotyping of Orthotopic Homograft (Syngeneic) of Murine Primary KPC Pancreatic Ductal Adenocarcinoma by Flow Cytometry

Homograft (syngeneic) tumors are the workhorse of today&#39;s immuno-oncology (I/O) preclinical research. The tumor microenvironment (TME), particularly its immune-components, is vital to the prognosis and prediction of treatment outcomes, especially those of immunotherapy. TME immune-components are composed of different subsets of tumor-infiltrating immune cells assessable by multi-color FACS. Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest malignances lacking good treatment options, thus an urgent and unmet medical need. One important reason for its non-responsiveness to various therapies (chemo-, targeted, I/O) has been its abundant TME, consisting of fibroblasts and leukocytes that protect tumor cells from these therapies. Orthotopically implanted PDAC is believed to more accurately recapture the TME of human pancreatic cancers than conventional subcutaneous (SC) models.
Homograft tumors (KPC) are transplants of mouse spontaneous PDAC originating from genetically engineered KPC-mice (KrasG12D/+/P53-/-/Pdx1-Cre) (KPC-GEMM). The primary tumor tissue is cut into small fragments (~2 mm3) and transplanted subcutaneously (SC) to the syngeneic recipients (C57BL/6, 7&#8211;9 weeks old). The homografts were then surgically orthotopically transplanted onto the pancreas of new C57BL/6 mice, along with SC-implantation, which reached tumor volumes of 300&#8211;1,000 mm3 by 17 days. Only tumors of 400&#8211;600 mm3 were harvested per approved autopsy procedure and cleaned to remove the adjacent non-tumor tissues. They were dissociated per protocol using a tissue dissociator into single-cell suspensions, followed by staining with designated panels of fluorescently-labeled antibodies for various markers of different immune cells (lymphoid, myeloid and NK, DCs). The stained samples were analyzed using multi-color FACS to determine numbers of immune cells of different lineages, as well as their relative percentage within tumors. The immune profiles of orthotopic tumors were then compared to those of SC tumors. The preliminary data demonstrated significantly elevated infiltrating TILs/TAMs in tumors over the pancreas, and higher B-cell infiltration into orthotopic rather than SC tumors.

Immunophenotyping of Orthotopic Homograft Syngeneic of Murine Primary KPC Pancreatic Ductal Adenocarcinoma by Flow Cytometry

The experimental procedure on the immunophenotyping of murine orthotopic PDAC homografts aims at profiling the tumor immuno-microenvironment. Tumors are orthotopically implanted via surgery. Tumors of 200&#8211;600 mm3 in size were harvested and dissociated to prepare single-cell suspensions, followed by multi-immune marker FACS analysis using different fluorescently-labeled antibodies.

Homograft (syngeneic) tumors are the workhorse of today&#39;s immuno-oncology (I/O) preclinical research. The tumor microenvironment (TME), particularly ...

Ultrasound-Guided Orthotopic Implantation of Murine Pancreatic Ductal Adenocarcinoma

The recent success of immune checkpoint blockade in melanoma and lung adenocarcinoma has galvanized the field of immuno-oncology as well as revealed the limitations of current treatments, as the majority of patients do not respond to immunotherapy. Development of accurate preclinical models to quickly identify novel and effective therapeutic combinations are critical to address this unmet clinical need. Pancreatic ductal adenocarcinoma (PDA) is a canonical example of an immune checkpoint blockade resistant tumor with only 2% of patients responding to immunotherapy. The genetically engineered KrasG12D+/-;Trp53R172H+/-;Pdx-1 Cre (KPC) mouse model of PDA recapitulates human disease and is a valuable tool for assessing therapies for immunotherapy resistant in the preclinical setting, but time to tumor onset is highly variable. Surgical orthotopic tumor implantation models of PDA maintain the immunobiological hallmarks of the KPC tissue-specific tumor microenvironment (TME) but require a time-intensive procedure and introduce aberrant inflammation. Here, we use an ultrasound-guided orthotopic tumor implantation model (UG-OTIM) to non-invasively inject KPC-derived PDA cell lines directly into the mouse pancreas. UG-OTIM tumors grow in the endogenous tissue site, faithfully recapitulate histological features of the PDA TME, and reach enrollment-sized tumors for preclinical studies by four weeks after injection with minimal seeding on the peritoneal wall. The UG-OTIM system described here is a rapid and reproducible tumor model that may allow for high throughput analysis of novel therapeutic combinations in the murine PDA TME.

We describe a protocol for the ultrasound guided implantation of murine-derived pancreatic ductal adenocarcinoma cell lines directly into the native tumor site. This approach resulted in pancreatic tumors detectable by ultrasound scanning within 2-4 weeks of injection, and significantly reduced the proportion tumor cell seeding on the peritoneal wall as compared to surgical orthotopic implantation.

The recent success of immune checkpoint blockade in melanoma and lung adenocarcinoma has galvanized the field of immuno-oncology as well as revealed the ...

Syngeneic Mouse Orthotopic Allografts to Model Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a very complex disease characterized by a heterogeneous tumor microenvironment made up of a diverse stroma, immune cells, vessels, nerves, and extracellular matrix components. Over the years, different mouse models of PDAC have been developed to address the challenges posed by its progression, metastatic potential, and phenotypic heterogeneity. Immunocompetent mouse orthotopic allografts of PDAC have shown good promise owing to their fast and reproducible tumor progression in comparison to genetically engineered mouse models. Moreover, combined with their ability to mimic the biological features observed in autochthonous PDAC, cell line-based orthotopic allograft mouse models enable large-scale in vivo experiments. Thus, these models are widely used in preclinical studies for rapid genotype-phenotype and drug-response analyses. The aim of this protocol is to provide a reproducible and robust approach to successfully inject primary mouse PDAC cell cultures into the pancreas of syngeneic recipient mice. In addition to the technical details, important information is given that must be considered before performing these experiments.

Syngeneic mouse orthotopic allografts of pancreatic ductal adenocarcinoma (PDAC) recapitulate the biology, phenotypes, and therapeutic responses of disease subtypes. Owing to their fast, reproducible tumor progression, they are widely used in preclinical studies. Here, we show common practices to generate these models, injecting syngeneic murine PDAC cultures into the pancreas.

Pancreatic ductal adenocarcinoma (PDAC) is a very complex disease characterized by a heterogeneous tumor microenvironment made up of a diverse stroma, ...

Reprogramming PDAC and Pancreatic Cells into Induced Pluripotent Stem Cells

Reprogramming Pancreatic Ductal Adenocarcinoma to Pluripotency

The generation of induced pluripotent stem cells (iPSCs) using transcription factors has been achieved from almost any differentiated cell type and has proved highly valuable for research and clinical applications. Interestingly, iPSC reprogramming of cancer cells, such as pancreatic ductal adenocarcinoma (PDAC), has been shown to revert the invasive PDAC phenotype and override the cancer epigenome. The differentiation of PDAC-derived iPSCs can recapitulate PDAC progression from its early pancreatic intraepithelial neoplasia (PanIN) precursor, revealing the molecular and cellular changes that occur early during PDAC progression. Therefore, PDAC-derived iPSCs can be used to model the earliest stages of PDAC for the discovery of early-detection diagnostic markers. This is particularly important for PDAC patients, who are typically diagnosed at the late metastatic stages due to a lack of reliable biomarkers for the earlier PanIN stages. However, reprogramming cancer cell lines, including PDAC, into pluripotency remains challenging, labor-intensive, and highly variable between different lines. Here, we describe a more consistent protocol for generating iPSCs from various human PDAC cell lines using bicistronic lentiviral vectors. The resulting iPSC lines are stable, showing no dependence on the exogenous expression of reprogramming factors or inducible drugs. Overall, this protocol facilitates the generation of a wide range of PDAC-derived iPSCs, which is essential for discovering early biomarkers that are more specific and representative of PDAC cases.

Author Spotlight: Reprogramming Cancer Cells to iPSCs to Study Disease Progression and Treatment Targets

The present protocol describes the reprogramming of Pancreatic Ductal Adenocarcinoma (PDAC) and normal pancreatic ductal epithelial cells into induced pluripotent stem cells (iPSCs). We provide an optimized and detailed, step-by-step procedure, from preparing lentivirus to establishing stable iPSC lines.

The generation of induced pluripotent stem cells (iPSCs) using transcription factors has been achieved from almost any differentiated cell type and has ...

Intrapulmonary Inoculation of Multicellular Spheroids to Model Orthotopic NSCLC

Construction of An Orthotopic Xenograft Model of Non-Small Cell Lung Cancer Mimicking Disease Progression and Predicting Drug Activities

Non-small cell lung cancer (NSCLC) is a highly lethal disease with a complex and heterogeneous tumor microenvironment. Currently, common animal models based on subcutaneous inoculation of cancer cell suspensions do not recapitulate the tumor microenvironment in NSCLC. Herein we describe a murine orthotopic lung cancer xenograft model that employs the intrapulmonary inoculation of three-dimensional multicellular spheroids (MCS). Specifically, fluorescent human NSCLC cells (A549-iRFP) were cultured in low-attachment 96-well microplates with collagen for 3 weeks to form MCS, which were then inoculated intercostally into the left lung of athymic nude mice to establish the orthotopic lung cancer model.
Compared with the original A549 cell line, MCS of the A549-iRFP cell line responded similarly to anticancer drugs. The long-wavelength fluorescent signal of the A549-iRFP cells correlated strongly with common markers of cancer cell growth, including spheroid volume, cell viability, and cellular protein level, thus allowing dynamic monitoring of the cancer growth in vivo by fluorescent imaging. After inoculation into mice, the A549-iRFP MCS xenograft reliably progressed through phases closely resembling the clinical stages of NSCLC, including the expansion of the primary tumor, the emergence of neighboring secondary tumors, and the metastases of cancer cells to the contralateral right lung and remote organs. Moreover, the model responded to the benchmark antilung cancer drug, cisplatin with the anticipated toxicity and slower cancer progression. Therefore, this murine orthotopic xenograft model of NSCLC would serve as a platform to recapitulate the disease&#39;s progression and facilitate the development of potential anticancer drugs.

Author Spotlight: Establishing a Murine Non-Small Cell Lung Cancer Model for Developing Nanoformulations of Anticancer Drugs

This study presents an orthotopic non-small cell lung cancer (NSCLC) model based on intrapulmonary inoculation of multicellular spheroids of fluorescent A549-iRFP cells. The model recapitulates clinical NSCLC stages and responds to cisplatin, according to dynamic in vivo monitoring of long-wavelength fluorescence.

Non-small cell lung cancer (NSCLC) is a highly lethal disease with a complex and heterogeneous tumor microenvironment. Currently, common animal models ...

Orthotopic Implantation and Peripheral Immune Cell Monitoring in the II-45 Syngeneic Rat Mesothelioma Model

The enormous upsurge of interest in immune-based treatments for cancer such as vaccines and immune checkpoint inhibitors, and increased understanding of the role of the tumor microenvironment in treatment response, collectively point to the need for immune-competent orthotopic models for pre-clinical testing of these new therapies. This paper demonstrates how to establish an orthotopic immune-competent rat model of pleural malignant mesothelioma. Monitoring disease progression in orthotopic models is confounded by the internal location of the tumors. To longitudinally monitor disease progression and its effect on circulating immune cells in this and other rat models of cancer, a single tube flow cytometry assay requiring only 25 &#181;l whole blood is described. This provides accurate quantification of seven immune parameters: total lymphocytes, monocytes and neutrophils, as well as the T-cell subsets CD4 and CD8, B-cells and Natural Killer cells. Different subsets of these parameters are useful in different circumstances and models, with the neutrophil to lymphocyte ratio having the greatest utility for monitoring disease progression in the mesothelioma model. Analyzing circulating immune cell levels using this single tube method may also assist in monitoring the response to immune-based treatments and understanding the underlying mechanisms leading to success or failure of treatment.

The generation of an orthotopic rat model of pleural malignant mesothelioma by implantation of II-45 mesothelioma cells into the pleural cavity of immune competent rats is presented. A flow cytometric method to analyze seven immune cell subsets in these animals from a 25 &#181;l&#160;blood sample is also described.

The enormous upsurge of interest in immune-based treatments for cancer such as vaccines and immune checkpoint inhibitors, and increased understanding of ...

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.

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

Pre-Conditioning the Airways of Mice with Bleomycin Increases the Efficiency of Orthotopic Lung Cancer Cell Engraftment

Lung cancer is a deadly treatment refractory disease that is biologically heterogeneous. To understand and effectively treat the full clinical spectrum of thoracic malignancies, additional animal models that can recapitulate diverse human lung cancer subtypes and stages are needed. Allograft or xenograft models are versatile and enable the quantification of tumorigenic capacity in vivo, using malignant cells of either murine or human origin. However, previously described methods of lung cancer cell engraftment have been performed in non-physiological sites, such as the flank of mice, due to the inefficiency of orthotopic transplantation of cells into the lungs. In this study, we describe a method to enhance orthotopic lung cancer cell engraftment by pre-conditioning the airways of mice with the fibrosis inducing agent bleomycin. As a proof-of-concept experiment, we applied this approach to engraft tumor cells of the lung adenocarcinoma subtype, obtained from either mouse or human sources, into various strains of mice. We demonstrate that injuring the airways with bleomycin prior to tumor cell injection increases the engraftment of tumor cells from 0-17% to 71-100%. Significantly, this method enhanced lung tumor incidence and subsequent outgrowth using different models and mouse strains. In addition, engrafted lung cancer cells disseminate from the lungs into relevant distant organs. Thus, we provide a protocol that can be used to establish and maintain new orthotopic models of lung cancer with limiting amounts of cells or biospecimen and to quantitatively assess the tumorigenic capacity of lung cancer cells in physiologically relevant settings.

We describe a method to significantly enhance orthotopic engraftment of lung cancer cells into the murine lungs by pre-conditioning the airways with injury. This approach may also be applied to study stromal interactions within the lung microenvironment, metastatic dissemination, lung cancer co-morbidities, and to more efficiently generate patient derived xenografts.

Lung cancer is a deadly treatment refractory disease that is biologically heterogeneous. To understand and effectively treat the full clinical spectrum of ...

Mouse Lung Preparation for Flow Cytometry: Generating Cell Suspension from Lung Tissue for Flow Cytometric Analysis

Source: Moll, H. P., et al. <a href="https://www.jove.com/v/58101/orthotopic-transplantation-syngeneic-lung-adenocarcinoma-cells-to">Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression.</a> J. Vis. Exp. (2019).
This video describes the preparation of mouse lung cell suspension for flow cytometric analysis to study PD-L1 expression of lung adenocarcinoma cells.

Source: Moll, H. P., et al. Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression. J. Vis. Exp. (2019).
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Orthotopic Transplantation of Syngeneic Lung Adenocarcinoma Cells to Study PD-L1 Expression

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