This work was supported by SAAG and SEED grants from the University of the Pacific. We thank Dr. William Chan for granting access to the Odyssey Infrared Imaging 205 System and Dr. John Livesey for granting access to the SpectraMax iD3 plate reader. We thank Dr. Melanie Felmlee for the technical advice on the animal protocols.

The animal study was performed with the approval of the Institutional Animal Care and Use Committee (IACUC) at the University of the Pacific (Animal Protocols 19R10 and 22R10). Eight Male athymic nude mice aged 5-6 weeks, weighing 20-25 g, bred with the referenced Rodent Diet and housed under pathogen-free (SPF) conditions, were used for the present study. Cages, bedding, and drinking water were autoclaved and changed regularly. A schematic of tumor inoculation in mice is shown in Figure 1. See the Table of Materials for details related to all materials and instruments used in this protocol.
1. Establishment of three-dimensional MCS of A549-iRFP cells
<ol>
	<li>Incubate A549-iRFP cells (human lung adenocarcinoma) in a humidified atmosphere with 5% CO2 at 37 &#176;C and grow them in complete growth medium DMEM containing 10% fetal bovine serum, 1% penicillin-streptomycin, and 1 &#181;g/mL puromycin.</li>
	<li>Seed A549-iRFP cells into 96-well ultra-low attachment, round-bottom spheroid microplate at a seeding density of 4,000 cells/well, using 100 &#181;L of complete growth medium supplemented with 0.3% collagen.</li>
	<li>Centrifuge the microplates at 300 &#215; g for 7 min at 4 &#176;C to facilitate the MCS formation. Examine the MCS morphology under a microscope to ensure cell aggregation after centrifugation.</li>
	<li>After 48 h, add 100 &#181;L of complete growth medium to each well to achieve a total volume of 200 &#181;L of growth medium per well.</li>
	<li>Replace 100 &#181;L of growth medium in each well with fresh complete growth medium every other day.</li>
</ol>
2. Characterization of A549-iRFP MCS
<ol>
	<li>Observe and image the MCS morphology using a microscope and estimate the MCS volume by simulation with the referenced software from MATLAB based on the phase-contrast microscope images.
	<ol>
		<li>Open one MCS image in ImageJ software.</li>
		<li>Use Freehand selections to select the edge of the MCS and add it to ROI Manager.</li>
		<li>Click Edit | Selection | Create Mask.</li>
		<li>Click Edit | Invert.</li>
		<li>Click File | Save As | Tiff.</li>
		<li>Open ReViSP software.</li>
		<li>Open the saved TIFF image by clicking Browse.</li>
		<li>Click Start to complete the MCS simulation.</li>
	</ol>
	</li>
	<li>Measure the iRFP fluorescent signal using the infrared imaging system at the 700 nm channel and quantify the fluorescent signal using software (e.g., Image Studio).
	<ol>
		<li>Open Image Studio software.</li>
		<li>In the Channels tab, select 700 and Intensity = 5.</li>
		<li>In the Scan Controls tab, select 84 &#181;m, Medium, 0.0 mm, and Flip Image. Keep everything else as default.</li>
		<li>Click Start to start scanning.</li>
	</ol>
	</li>
	<li>Assess and quantify cell viability using the 3D cell viability assay according to the vendor protocol.</li>
	<li>Assess and quantify cellular protein using the BCA Assay according to the vendor protocol.</li>
</ol>
3. MCS selection for tumor inoculation
NOTE: After MCS are seeded into spheroid microplates and grown for 2-3 weeks with regular growth medium exchange, select MCS with the following appropriate characteristics for tumor inoculation.
<ol>
	<li>Observe the MCS morphology under a microscope and choose MCS with a round shape with overall smooth edges but with 5-10 rough buddings (arrows in Figure 2F) and a diameter within the range of 700-800 &#181;m.</li>
	<li>Measure the iRFP fluorescence (refer to step 2.2) and select the MCS whose fluorescent signals are within one standard deviation of the average.</li>
</ol>
4. Intrapulmonary MCS inoculation
NOTE: Use 70% isopropyl alcohol spray to clean the surgical station and the tools before handling the animals. The surgeon should wear sterile gloves throughout the surgical procedures.
<ol>
	<li>Anesthetize each mouse with an IP injection of 80 mg/kg ketamine and 12 mg/kg xylazine; pinch the mouse feet with forceps to ensure full anesthesia.</li>
	<li>Inject 0.05 mg/kg of buprenorphine hydrochloride subcutaneously to reduce the pain.</li>
	<li>Apply ophthalmic ointment on the eyes to prevent dryness.</li>
	<li>Place the mouse on an infrared heat pad in a dorsal posture and secure the limbs in a stretching position with tapes. 
	NOTE: Provide heat support to the anesthetized mouse throughout the whole surgical procedure.</li>
	<li>Disinfect the back skin by swabbing with alternating rounds of iodine and alcohol, at least three times each.</li>
	<li>Cut a 0.5-1 cm incision using surgical scissors on the left back side (Figure 1B). Carefully use forceps to separate the muscle and fat tissues until the chest wall and lung motion are visible.</li>
	<li>Transfer one selected MCS from a microplate into a glass Petri dish containing ice-cold PBS, using a pipette.</li>
	<li>Attach a 20 G needle onto a 100 &#181;L glass syringe, precool them on ice, and draw 20 &#181;L of a precooled mixture of PBS and Matrigel (1:1 v/v).</li>
	<li>Use the syringe to quickly aspirate one MCS from the Petri dish in a minimum volume of PBS-Matrigel mixture, keeping the MCS in the metal part of the needle. 
	NOTE: Keep a tight grip on the syringe and plunger to prevent the MCS from slipping out of the needle.</li>
	<li>Gently insert the needle vertically between two rib bones to ~3 mm depth and slowly inject all the 20 &#181;L PBS and Matrigel mixture that contains the MCS. 
	NOTE: Avoid excessive force during the insertion to prevent damage to the lung, vasculature, or heart.</li>
	<li>Carefully remove the needle and apply triple antibiotic ointment to the wound.</li>
	<li>Seal the incision with surgical clips, which are to be removed after 2 weeks. 
	NOTE: Do not suture the incision because the suture lines may interfere with fluorescence imaging. The nude mice are able to heal naturally after surgery.</li>
	<li>Place the animal on an infrared heat pad and cover it with laboratory wipes to maintain the body temperature. Monitor the animal for at least 30-60 min until it wakes up and moves properly.</li>
	<li>Inject 0.05 mg/kg of buprenorphine hydrochloride subcutaneously every 8 h for the first 48 h to reduce the pain.</li>
</ol>
5. Postsurgical monitoring
<ol>
	<li>Measure the body weight every 3-4 days.</li>
	<li>Measure the iRFP fluorescent signal from the tumor xenograft every 3-4 days on a small animal imaging system at 700 nm channel in four postures: left, right, dorsal, and ventral, while the mice are kept under anesthesia by isoflurane inhalation (flow rate: 1.5-2 L/min oxygen containing 1.5% isoflurane) over 2-3 min. 
	NOTE: Use 70% isopropyl alcohol spray to clean the small animal imaging system before putting animal onto the imaging station. The surgeon should wear sterile gloves throughout the surgical procedures.</li>
	<li>Quantify the net fluorescent intensity of the xenograft cancer in vivo using software (e.g., Image Studio).
	<ol>
		<li>Use a fixed rectangle (A1, 200 x 125 pixels) as the sampling window for the chest area of the mice.</li>
		<li>Use the free-hand function to trace the shape of the mice within the rectangle (A1) and measure the fluorescent intensity (F1) in area A1.</li>
		<li>Use another smaller rectangle (A2,&#160;25 x 40 pixels) to measure the background fluorescence (F2) of the mice in the thigh area.</li>
		<li>Use equation (1) to calculate the net fluorescent intensity of the xenograft cancer in each mouse: 
		<img alt="Equation 1" src="/files/ftp_upload/66787/66787eq01.jpg" style="margin: auto;" />&#160; &#160; &#160;(1)</li>
	</ol>
	</li>
</ol>

Intrapulmonary Inoculation of Multicellular Spheroids to Model Orthotopic NSCLC

<ol>
	<li>Siegel, R. L., Miller, K. D., Jemal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+statistics.">Cancer statistics.</a> CA Cancer J Clin. 70 (1), 7-30 (2020).</li><li>Bray, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+cancer+statistics+2018:+Globocan+estimates+of+incidence+and+mortality+worldwide+for+36+cancers+in+185+countries.">Global cancer statistics 2018: Globocan estimates of incidence and mortality worldwide for 36 cancers in 185 countries.</a> CA Cancer J Clin. 68 (6), 394-424 (2018).</li><li>Travis, W. D., Brambilla, E., Riely, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+pathologic+classification+of+lung+cancer:+Relevance+for+clinical+practice+and+clinical+trials.">New pathologic classification of lung cancer: Relevance for clinical practice and clinical trials.</a> J Clin Oncol. 31 (8), 992-1001 (2013).</li><li>Ducote, T. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+artificial+intelligence+to+identify+tumor+microenvironment+heterogeneity+in+non-small+cell+lung+cancers.">Using artificial intelligence to identify tumor microenvironment heterogeneity in non-small cell lung cancers.</a> Lab Invest. 103 (8), 100176 (2023).</li><li>Lim, Z. F., Ma, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Emerging+insights+of+tumor+heterogeneity+and+drug+resistance+mechanisms+in+lung+cancer+targeted+therapy.">Emerging insights of tumor heterogeneity and drug resistance mechanisms in lung cancer targeted therapy.</a> J Hematol Oncol. 12 (1), 134 (2019).</li><li>Wang, D. C., Wang, W., Zhu, B., Wang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lung+cancer+heterogeneity+and+new+strategies+for+drug+therapy.">Lung cancer heterogeneity and new strategies for drug therapy.</a> Annu Rev Pharmacol Toxicol. 58, 531-546 (2018).</li><li>Peterson, J. K., Houghton, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrating+pharmacology+and+in+vivo+cancer+models+in+preclinical+and+clinical+drug+development.">Integrating pharmacology and in vivo cancer models in preclinical and clinical drug development.</a> Eur J Cancer. 40 (6), 837-844 (2004).</li><li>Madero-Visbal, R. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioluminescence+imaging+correlates+with+tumor+progression+in+an+orthotopic+mouse+model+of+lung+cancer.">Bioluminescence imaging correlates with tumor progression in an orthotopic mouse model of lung cancer.</a> Surg Oncol. 21 (1), 23-29 (2012).</li><li>Mclemore, T. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+intrapulmonary+model+for+orthotopic+propagation+of+human+lung+cancers+in+athymic+nude+mice.">Novel intrapulmonary model for orthotopic propagation of human lung cancers in athymic nude mice.</a> Cancer Res. 47 (19), 5132-5140 (1987).</li><li>Zanoni, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3d+tumor+spheroid+models+for+in+vitro+therapeutic+screening:+A+systematic+approach+to+enhance+the+biological+relevance+of+data+obtained.">3d tumor spheroid models for in vitro therapeutic screening: A systematic approach to enhance the biological relevance of data obtained.</a> Sci Rep. 6, 19103 (2016).</li><li>Kim, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+tissue+culture+models+in+cancer+biology.">Three-dimensional tissue culture models in cancer biology.</a> Semin Cancer Biol. 15 (5), 365-377 (2005).</li><li>Chaicharoenaudomrung, N., Kunhorm, P., Noisa, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+cell+culture+systems+as+an+in+vitro+platform+for+cancer+and+stem+cell+modeling.">Three-dimensional cell culture systems as an in vitro platform for cancer and stem cell modeling.</a> World J Stem Cells. 11 (12), 1065-1083 (2019).</li><li>Mehta, G., Hsiao, A. Y., Ingram, M., Luker, G. D., Takayama, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Opportunities+and+challenges+for+use+of+tumor+spheroids+as+models+to+test+drug+delivery+and+efficacy.">Opportunities and challenges for use of tumor spheroids as models to test drug delivery and efficacy.</a> J Control Release. 164 (2), 192-204 (2012).</li><li>Huang, B. W., Gao, J. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+3d+cultured+multicellular+spheroid+tumor+models+in+tumor-targeted+drug+delivery+system+research.">Application of 3d cultured multicellular spheroid tumor models in tumor-targeted drug delivery system research.</a> J Control Release. 270, 246-259 (2018).</li><li>Hirschhaeuser, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multicellular+tumor+spheroids:+An+underestimated+tool+is+catching+up+again.">Multicellular tumor spheroids: An underestimated tool is catching up again.</a> J Biotechnol. 148 (1), 3-15 (2010).</li><li>Sethi, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3d+tumor+tissue+analogs+and+their+orthotopic+implants+for+understanding+tumor-targeting+of+microenvironment-responsive+nanosized+chemotherapy+and+radiation.">3d tumor tissue analogs and their orthotopic implants for understanding tumor-targeting of microenvironment-responsive nanosized chemotherapy and radiation.</a> Nanomedicine. 11 (8), 2013-2023 (2015).</li><li>Valta, M. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spheroid+culture+of+lucap+136+patient-derived+xenograft+enables+versatile+preclinical+models+of+prostate+cancer.">Spheroid culture of lucap 136 patient-derived xenograft enables versatile preclinical models of prostate cancer.</a> Clin Exp Metastasis. 33 (4), 325-337 (2016).</li><li>Huang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrapulmonary+inoculation+of+multicellular+spheroids+to+construct+an+orthotopic+lung+cancer+xenograft+model+that+mimics+four+clinical+stages+of+non-small+cell+lung+cancer.">Intrapulmonary inoculation of multicellular spheroids to construct an orthotopic lung cancer xenograft model that mimics four clinical stages of non-small cell lung cancer.</a> J Pharmacol Toxicol Methods. , 106885 (2020).</li><li>Lemjabbar-Alaoui, H., Hassan, O. U., Yang, Y. W., Buchanan, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lung+cancer:+Biology+and+treatment+options.">Lung cancer: Biology and treatment options.</a> Biochim Biophys Acta. 1856 (2), 189-210 (2015).</li><li>Detterbeck, F. C., Boffa, D. J., Kim, A. W., Tanoue, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+eighth+edition+lung+cancer+stage+classification.">The eighth edition lung cancer stage classification.</a> Chest. 151 (1), 193-203 (2017).</li></ol>

The authors have no conflicts of interest to declare.

The construction of A549-iRFP MCS is a straightforward and highly reproducible lab procedure and can be translated to MCS formation for multiple cell lines. The MCS generated with the aid of centrifugation and collagen exhibits a more integral and solid-tumor-like structure within 3-4 days. This method ensures the formation of robust spheroids that maintain their integral structure for extended periods, typically 2-3 weeks or even longer until small buddings begin to emerge. By employing centrifugation and collagen, we s...

Among all oncological disorders, lung cancer not only inflicts the highest life loss but also claims the second-highest number of new patients every year in the US1. This devastating malignancy stands as a major obstacle in modern healthcare, urging for a deeper understanding of its intricate biology and more efficacious therapeutic modalities2. Non-small cell lung cancer (NSCLC) accounts for 85% of lung cancer and tends to develop into solid tumors3. One of the foremost challenges in lung cancer is the dynamic and heterogeneous tumor microenvironment, which profoundly influences the cancer&#39;s progression and responses to therapeutic interventions4,5,6. A deeper understanding of the interplay between cancer cells and their microenvironment at different stages of NSCLC calls for refined pathological models that recapitulate the histological features of NSCLC progression.
In this regard, orthotopic animal models emerge as a promising avenue for NSCLC research. Unlike commonly employed subcutaneous xenograft models7, orthotopic models feature cancer cells that are directly inoculated into the organ of origin. For lung cancer, this means implanting cancer cells directly into the lung tissue8,9. Consequently, orthotopic models of lung cancer better mimic the native tumor microenvironment, including the neighboring tissues, vessels, and immune components, thus improving their physiological and clinical relevance.
Three-dimensional multicellular spheroids (MCS) represent another promising approach to recapitulating features of the tumor environment. Most cancers are characterized by their complex tumor microenvironment, including the various cell-cell interactions, the extracellular matrix, and the gradients in oxygen and nutrients10,11. Traditional 2D cell cultures lack the spatial and structural complexity to recapitulate these tumor-specific features12. In contrast, MCS of appropriate size feature a heterogeneous structure with a hypoxic and necrotic core, which recapitulates not only the intratumoral microenvironment but also the physiological barrier against drug penetration, which is a major mechanism of drug resistance in anticancer therapy13,14,15.
Taking advantage of both the orthotopic animal models and the MCS culturing techniques, MCS have been inoculated to immune-compromised mice to successfully construct orthotopic models of breast cancer and prostate cancer16,17. Herein, we report the detailed methodology to construct and characterize a murine orthotopic xenograft model of lung cancer. This method employs the intrapulmonary inoculation of 3D MCS derived from fluorescent human lung cancer cells (A549-iRFP)18. This model offers an exceptional opportunity to observe the in vivo progression of lung cancer through stages that closely parallel the four clinical stages of NSCLC. Furthermore, the xenograft cancer of this model responded to the clinically established antilung cancer drug, cisplatin.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>100 &#181;L Glass Syringe</td>
			<td>Hamilton</td>
			<td>Part/REF #80601</td>
			<td></td>
		</tr>
		<tr>
			<td>20 G Needle</td>
			<td>Thermo Fisher Scientific Inc.</td>
			<td>14 826D</td>
			<td></td>
		</tr>
		<tr>
			<td>96-well Ultra-Low-Attachment Spheroid Microplate&#160;</td>
			<td>Corning</td>
			<td>15-100-173</td>
			<td></td>
		</tr>
		<tr>
			<td>A549-iRFP</td>
			<td>Imanis Life Sciences&#160;</td>
			<td>CL082-STAN</td>
			<td></td>
		</tr>
		<tr>
			<td>AIN-93M Mature Rodent Diet&#160;</td>
			<td>Research Diets, Inc.</td>
			<td>D10012M</td>
			<td></td>
		</tr>
		<tr>
			<td>Athymic Nude Mouse</td>
			<td>Charles River Laboratories, Inc.</td>
			<td>Strain Code: 490; homozygous</td>
			<td></td>
		</tr>
		<tr>
			<td>BCA</td>
			<td>Pierce</td>
			<td>23227</td>
			<td></td>
		</tr>
		<tr>
			<td>Buprenorphine Hydrochloride</td>
			<td>Patterson Veterinary</td>
			<td>NDC Number: 42023-179-05</td>
			<td></td>
		</tr>
		<tr>
			<td>CellTiter-Glo 3D Cell Viability Assay</td>
			<td>Promega</td>
			<td>G9683</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen</td>
			<td>Gibco</td>
			<td>A1064401&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Corning</td>
			<td>MT10013CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Cytiva HyClone</td>
			<td>SH3039603</td>
			<td></td>
		</tr>
		<tr>
			<td>ImageJ</td>
			<td>Open source tool (https://imagej.net/ij/)</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Image Studio&#160;</td>
			<td>LI-COR</td>
			<td>Version 5.2</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Patterson Veterinary</td>
			<td>NDC Number: 17033-0091-25</td>
			<td></td>
		</tr>
		<tr>
			<td>Ketamine</td>
			<td>Patterson Veterinary</td>
			<td>NDC Number: 50989-0161-06</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope&#160;</td>
			<td>Keyence</td>
			<td>Model number: BZ-X710</td>
			<td></td>
		</tr>
		<tr>
			<td>Matrigel</td>
			<td>Corning</td>
			<td>CB-40234</td>
			<td></td>
		</tr>
		<tr>
			<td>Odyssey Infrared Imaging 205 System&#160;</td>
			<td>LI-COR</td>
			<td>Model number: 9140</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Corning</td>
			<td>MT21040CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Pearl Trilogy small animal imaging system&#160;</td>
			<td>LI-COR</td>
			<td>Model number: 9430</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin&#160;</td>
			<td>Corning</td>
			<td>MT30002CI</td>
			<td></td>
		</tr>
		<tr>
			<td>Puromycin</td>
			<td>Thermo Fisher Scientific Inc.</td>
			<td>AAJ67236XF</td>
			<td></td>
		</tr>
		<tr>
			<td>ReViSP software from MATLAB&#160;</td>
			<td>Open source tool on Sourceforge (https://sourceforge.net/projects/revisp/)</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical Clips--AutoClip System</td>
			<td>Fine Science Tools</td>
			<td>12020-00</td>
			<td></td>
		</tr>
		<tr>
			<td>Xylazine</td>
			<td>Patterson Veterinary</td>
			<td>NDC Number: 61133-6017-01</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

Characterization of A549-iRFP MCS 
A549-iRFP MCS were successfully cultured in spheroid microplates with the assistance of collagen and centrifugation. When MCS reached a diameter of approximately 500 &#181;m after 1 week, both A549 and A549-iRFP MCS were exposed to a variety of anticancer drugs and formulations for 3 days and then maintained in drug-free growth medium for 4 additional days. The A549-iRFP MCS exhibited a response pattern closely mirroring that of the parent A549 cells. A549 and A549...

Read this Scientific Article Protocol about Construction of An Orthotopic Xenograft Model of Non-small Cell Lung Cancer Mimicking Disease Progression and Predicting Drug Activities at JoVE.com

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.

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 ...

construction-an-orthotopic-xenograft-model-non-small-cell-lung-cancer

Research

JoVE Journal

Cancer Research

813 Views.  University of the Pacific. 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. 

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

Fluorescent Orthotopic Mouse Model of Pancreatic Cancer

Pancreatic cancer remains one of the cancers for which survival has not improved substantially in the last few decades. Only 7% of diagnosed patients will survive longer than five years. In order to understand and mimic the microenvironment of pancreatic tumors, we utilized a murine orthotopic model of pancreatic cancer that allows non-invasive imaging of tumor progression in real time. Pancreatic cancer cells expressing green fluorescent protein (PANC-1 GFP) were suspended in basement membrane matrix, high concentration, (e.g., Matrigel HC) with serum-free media and then injected into the tail of the pancreas via laparotomy. The cell suspension in the high concentration basement membrane matrix becomes a gel-like substance once it reaches room temperature; therefore, it gels when it comes in contact with the pancreas, creating a seal at the injection site and preventing any cell leakage. Tumor growth and metastasis to other organs are monitored in live animals by using fluorescence. It is critical to use the appropriate filters for excitation and emission of GFP. The steps for the orthotopic implantation are detailed in this article so researchers can easily replicate the procedure in nude mice. The main steps of this protocol are preparation of the cell suspension, surgical implantation, and whole body fluorescent in vivo imaging. This orthotopic model is designed to investigate the efficacy of novel therapeutics on primary and metastatic tumors.

A procedure to implant green fluorescent protein-expressing pancreatic cancer cells (PANC-1 GFP) orthotopically into the pancreas of Balb-c Ola Hsd-Fox1nu mice to assess tumor progression and metastasis is presented here.

Pancreatic cancer remains one of the cancers for which survival has not improved substantially in the last few decades. Only 7% of diagnosed patients will ...

Isolation of Circulating Tumor Cells in an Orthotopic Mouse Model of Colorectal Cancer

Despite the advantages of easy applicability and cost-effectiveness, subcutaneous mouse models have severe limitations and do not accurately simulate tumor biology and tumor cell dissemination. Orthotopic mouse models have been introduced to overcome these limitations; however, such models are technically demanding, especially in hollow organs such as the large bowel. In order to produce uniform tumors which reliably grow and metastasize, standardized techniques of tumor cell preparation and injection are critical. 
We have developed an orthotopic mouse model of colorectal cancer (CRC) which develops highly uniform tumors and can be used for tumor biology studies as well as therapeutic trials. Tumor cells from either primary tumors, 2-dimensional (2D) cell lines or 3-dimensional (3D) organoids are injected into the cecum and, depending on the metastatic potential of the injected tumor cells, form highly metastatic tumors. In addition, CTCs can be found regularly. We here describe the technique of tumor cell preparation from both 2D cell lines and 3D organoids as well as primary tumor tissue, the surgical and injection techniques as well as the isolation of CTCs from the tumor-bearing mice, and present tips for troubleshooting.

We describe the establishment of orthotopic colorectal tumors via injection of tumor cells or organoids into the cecum of mice and the subsequent isolation of circulating tumor cells (CTCs) from this model.

Despite the advantages of easy applicability and cost-effectiveness, subcutaneous mouse models have severe limitations and do not accurately simulate ...

Tumor Engraftment in a Xenograft Mouse Model of Human Mantle Cell Lymphoma

B lymphocytes are key players in immune cell circulation and they mainly home to and reside in lymphoid organs. While normal B cells only proliferate when stimulated by T lymphocytes, oncogenic B cells survive and expand autonomously in undefined organ niches. Mantle cell lymphoma (MCL) is one such B cell disorder, where the median survival rate of patients is 4 - 5 years. This calls for the need of effective mechanisms by which the homing and engraftment of these cells are blocked in order to increase the survival and longevity of patients. Therefore, the effort to develop a xenograft mouse model to study the efficacy of MCL therapeutics by blocking the homing mechanism in vivo is of utmost importance. Development of animal recipients for human cell xenotransplantation to test early stage drugs have long been pursued, as relevant preclinical mouse models are crucial to screen new therapeutic agents. This animal model is developed to avoid human graft rejection and to establish a model for human diseases, and it may be an extremely useful tool to study disease progression of different lymphoma types and to perform preclinical testing of candidate drugs for hematologic malignancies, like MCL. We established a xenograft mouse model that will serve as an excellent resource to study and develop novel therapeutic approaches for MCL.

Mantle cell lymphoma (MCL) is a difficult to treat B cell disorder and it is equally difficult to establish a xenograft mouse model of primary MCL to study and develop therapeutics. Here, we describe the successful establishment of MCL xenografts in mice to help understand its underlying biology.

B lymphocytes are key players in immune cell circulation and they mainly home to and reside in lymphoid organs. While normal B cells only proliferate when ...

Using 22C3 Anti-PD-L1 Antibody Concentrate on Biopsy and Cytology Samples from Non-small Cell Lung Cancer Patients

Pembrolizumab monotherapy has been approved for the first- and second-line treatment of patients with PD-L1-expressing advanced non-small cell lung cancer (NSCLC). Testing for PD-L1 expression with the PD-L1 immunohistochemistry (IHC) 22C3 companion diagnostic assay, which gives a tumor proportion score (TPS), has been validated on tumor tissue. We developed an optimized laboratory-developed test (LDT) that uses the 22C3 antibody (Ab) concentrate on a widely available IHC autostainer for biopsy and cytology specimens. The PD-L1 TPS was evaluated with 120 paired whole-tumor tissue sections and biopsy samples and with 70 paired biopsy and cytology samples (bronchial washes, n = 40; pleural effusions, n = 30). The 22C3 Ab concentrate-based LDT showed a high concordance rate between biopsy (~100%) and cytology (~95%) specimens when compared to PD-L1 IHC expression determined using the PD-L1 IHC 22C3 companion assay at both TPS cut points (&#8805;1%, &#8805;50%). The optimized LDT presented here, using the 22C3 Ab concentrate to determine the PD-L1 expression in both tumor tissue and in cytology specimens, will expand the ability of laboratories worldwide to assess the eligibility of patients with NSCLC for treatment with pembrolizumab monotherapy in a reliable and reproducible manner.

To expand the ability of laboratories worldwide to assess the eligibility of patients with lung cancer for treatment with pembrolizumab, in a reliable and reproducible manner, we developed an assay that uses the 22C3 antibody concentrate on a widely available immunohistochemical autostainer, for both biopsy and cytology specimens.

Pembrolizumab monotherapy has been approved for the first- and second-line treatment of patients with PD-L1-expressing advanced non-small cell lung cancer ...

Patient-derived Orthotopic Xenograft Models for Human Urothelial Cell Carcinoma and Colorectal Cancer Tumor Growth and Spontaneous Metastasis

Cancer patients have poor prognoses when lymph node (LN) involvement is present in both high-grade urothelial cell carcinoma (HG-UCC) of the bladder and colorectal cancer (CRC). More than 50% of patients with muscle-invasive UCC, despite curative therapy for clinically-localized disease, will develop metastases and die within 5 years, and metastatic CRC is a leading cause of cancer-related deaths in the US. Xenograft models that consistently mimic UCC and CRC metastasis seen in patients are needed. This study aims to generate patient-derived orthotopic xenograft (PDOX) models of UCC and CRC for primary tumor growth and spontaneous metastases under the influence of LN stromal cells mimicking the progression of human metastatic diseases for drug screening. Fresh UCC and CRC tumors were obtained from consented patients undergoing resection for HG-UCC and colorectal adenocarcinoma, respectively. Co-inoculated with LN stromal cell (LNSC) analog HK cells, luciferase-tagged UCC cells were intra-vesically (IB) instilled into female non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, and CRC cells were intra-rectally (IR) injected into male NOD/SCID mice. Tumor growth and metastasis were monitored weekly using bioluminescence imaging (BLI). Upon sacrifice, primary tumors and mouse organs were harvested, weighed, and formalin-fixed for Hematoxylin and Eosin and immunohistochemistry staining. In our unique PDOX models, xenograft tumors resemble patient pre-implantation tumors. In the presence of HK cells, both models have high tumor implantation rates measured by BLI and tumor weights, 83.3% for UCC and 96.9% for CRC, and high distant organ metastasis rates (33.3% detected liver or lung metastasis for UCC and 53.1% for CRC). In addition, both models have zero mortality from the procedure. We have established unique, reproducible PDOX models for human HG-UCC and CRC, which allow for tumor formation, growth, and metastasis studies. With these models, testing of novel therapeutic drugs can be performed efficiently and in a clinically-mimetic manner.

This protocol describes the generation of patient-derived orthotopic xenograft models by intra-vesically instilling high-grade urothelial cell carcinoma cells or intra-rectally injecting colorectal cancer cells into non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice for primary tumor growth and spontaneous metastases under the influence of lymph node stromal cells, which mimics the progression of human metastatic diseases.

Cancer patients have poor prognoses when lymph node (LN) involvement is present in both high-grade urothelial cell carcinoma (HG-UCC) of the bladder and ...

Patient-derived Heterogeneous Xenograft Model of Pancreatic Cancer Using Zebrafish Larvae as Hosts for Comparative Drug Assessment

Patient-derived tumor xenograft (PDX) and cell-derived tumor xenograft (CDX) are important techniques for preclinical assessment, medication guidance and basic cancer researches. Generations of PDX models in traditional host mice are time-consuming and only working for a small proportion of samples. Recently, zebrafish PDX (zPDX) has emerged as a unique host system, with the characteristics of small-scale and high efficiency. Here, we describe an optimized methodology for generating a dual fluorescence-labeled tumor xenograft model for comparative chemotherapy assessment in zPDX models. Tumor cells and fibroblasts were enriched from freshly-harvested or frozen pancreatic cancer tissue at different culture conditions. Both cell groups were labeled by lentivirus expressing green or red fluorescent proteins, as well as an anti-apoptosis gene BCL2L1. The transfected cells were pre-mixed and co-injected into the 2 dpf larval zebrafish that were then bred in modified E3 medium at 32 &#176;C. The xenograft models were treated by chemotherapy drugs and/or BCL2L1 inhibitor, and the viabilities of both tumor cells and fibroblasts were investigated simultaneously. In summary, this protocol allows researchers to quickly generate a large amount of zPDX models with a heterogeneous tumor microenvironment and provides a longer observation window and a more precise quantitation in assessing the efficiency of drug candidates.

This protocol describes optimization procedures in a virus-based dual fluorescence-labeled tumor xenograft model using larval zebrafish as hosts. This heterogeneous xenograft model mimics the tissue composition of pancreatic cancer microenvironment in vivo and serves as a more precise tool for assessing drug responses in personalized zPDX (zebrafish patient-derived xenograft) models.

Patient-derived tumor xenograft (PDX) and cell-derived tumor xenograft (CDX) are important techniques for preclinical assessment, medication guidance and ...

Semi-automatic PD-L1 Characterization and Enumeration of Circulating Tumor Cells from Non-small Cell Lung Cancer Patients by Immunofluorescence

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL of blood) warrant a poor prognosis and are correlated with shorter overall survival in several cancers (e.g., breast, prostate and colorectal). Currently, the anti-EpCAM-coated magnetic bead-based CTC capturing system is the gold standard test approved by the U.S. Food and Drug Administration (FDA) for enumerating CTCs in the bloodstream. This test is based on the use of magnetic beads coated with anti-EpCAM markers, which specifically target epithelial cancer cells. Many studies have illustrated that EpCAM is not the optimal marker for CTC detection. Indeed, CTCs are a heterogeneous subpopulation of cancer cells and are able to undergo an epithelial-to-mesenchymal transition (EMT) associated with metastatic proliferation and invasion. These CTCs are able to reduce the expression of cell surface epithelial marker EpCAM, while increasing mesenchymal markers such as vimentin. To address this technical hurdle, other isolation methods based on physical properties of CTCs have been developed. Microfluidic technologies enable a label-free approach to CTC enrichment from whole blood samples. The spiral microfluidic technology uses the inertial and Dean drag forces with continuous flow in curved channels generated within a spiral microfluidic chip. The cells are separated based on the differences in size and plasticity between normal blood cells and tumoral cells. This protocol details the different steps to characterize the programmed death-ligand 1 (PD-L1) expression of CTCs, combining a spiral microfluidic device with customizable immunofluorescence (IF) marker set.

The characterization of circulating tumor cells (CTCs) is a popular topic in translational research. This protocol describes a semi-automatic immunofluorescence (IF) assay for PD-L1 characterization and enumeration of CTCs in non-small cell lung cancer (NSCLC) patient samples.

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL ...

Generation of a Liver Orthotopic Human Uveal Melanoma Xenograft Platform in Immunodeficient Mice

In recent decades, subcutaneously implanted patient-derived xenograft tumors or cultured human cell lines have been increasingly recognized as more representative models to study human cancers in immunodeficient mice than traditional established human cell lines in vitro. Recently, orthotopically implanted patient-derived tumor xenograft (PDX) models in mice have been developed to better replicate features of patient tumors. A liver orthotopic xenograft mouse model is expected to be a useful cancer research platform, providing insights into tumor biology and drug therapy. However, liver orthotopic tumor implantation is generally complicated. Here we describe our protocols for the orthotopic implantation of patient-derived liver-metastatic uveal melanoma tumors. We cultured human liver metastatic uveal melanoma cell lines into immunodeficient mice. The protocols can result in consistently high technical success rates using either a surgical orthotopic implantation technique with chunks of patient-derived uveal melanoma tumor or a needle injection technique with cultured human cell line. We also describe protocols for CT scanning to detect interior liver tumors and for re-implantation techniques using cryopreserved tumors to achieve re-engraftment. Together, these protocols provide a better platform for liver orthotopic tumor mouse models of liver metastatic uveal melanoma in translational research.

Orthotopic human liver metastatic uveal melanoma xenograft mouse models were created using surgical orthotopic implantation techniques with patient-derived tumor chunk and needle injection techniques with cultured human uveal melanoma cell lines.

In recent decades, subcutaneously implanted patient-derived xenograft tumors or cultured human cell lines have been increasingly recognized as more ...

Detection of Lung Tumor Progression in Mice by Ultrasound Imaging

With ~1.6 million victims per year, lung cancer contributes tremendously to the worldwide burden of cancer. Lung cancer is partly driven by genetic alterations in oncogenes such as the KRAS oncogene, which constitutes ~25% of lung cancer cases. The difficulty in therapeutically targeting KRAS-driven lung cancer partly stems from having poor models that can mimic the progression of the disease in the lab. We describe a method that permits the relative quantification of primary KRAS lung tumors in a Cre-inducible LSL-KRAS G12D mouse model via ultrasound imaging. This method relies on brightness (B)-mode acquisition of the lung parenchyma. Tumors that are initially formed in this model are visualized as B-lines and can be quantified by counting the number of B-lines present in the acquired images. These would represent the relative tumor number formed on the surface of the mouse lung. As the formed tumors develop with time, they are perceived as deep clefts within the lung parenchyma. Since the circumference of the formed tumor is well-defined, calculating the relative tumor volume is achieved by measuring the length and width of the tumor and applying them in the formula used for tumor caliper measurements. Ultrasound imaging is a non-invasive, fast and user-friendly technique that is often used for tumor quantifications in mice. Although artifacts may appear when obtaining ultrasound images, it has been shown that this imaging technique is more advantageous for tumor quantifications in mice compared to other imaging techniques such as computed tomography (CT) imaging and bioluminescence imaging (BLI). Researchers can investigate novel therapeutic targets using this technique by comparing lung tumor initiation and progression between different groups of mice.

This protocol describes the steps taken to induce KRAS lung tumors in mice as well as the quantification of formed tumors by ultrasound imaging. Small tumors are visualized in early timepoints as B-lines. At later timepoints, relative tumor volume measurements are achieved by the measurement tool in the ultrasound software.

With ~1.6 million victims per year, lung cancer contributes tremendously to the worldwide burden of cancer. Lung cancer is partly driven by genetic ...

Multidimensional Coculture System to Model Lung Squamous Carcinoma Progression

Tumor-stroma interactions play a critical role in the development of lung squamous carcinoma (LUSC). However, understanding how these dynamic interactions contribute to tissue architectural changes observed during tumorigenesis remains challenging due to the lack of appropriate models. In this protocol, we describe the generation of a 3D coculture model using a LUSC primary cell culture known as TUM622. TUM622 cells were established from a LUSC patient-derived xenograft (PDX) and have the unique property to form acinar-like structures when seeded in a basement membrane matrix. We demonstrate that TUM622 acini in 3D coculture recapitulate key features of tissue architecture during LUSC progression as well as the dynamic interactions between LUSC cells and components of the tumor microenvironment (TME), including the extracellular matrix (ECM) and cancer-associated fibroblasts (CAFs). We further adapt our principal 3D culturing protocol to demonstrate how this system could be utilized for various downstream analyses. Overall, this organoid model creates a biologically rich and adaptable platform that enables one to gain insight into the cell-intrinsic and extrinsic mechanisms that promote the disruption of epithelial architectures during carcinoma progression and will aid the search for new therapeutic targets and diagnostic markers.

An in vitro model system was developed to capture tissue architectural changes during lung squamous carcinoma (LUSC) progression in a 3-dimensional (3D) co-culture with cancer-associated fibroblasts (CAFs). This organoid system provides a unique platform to investigate the roles of diverse tumor cell-intrinsic and extrinsic changes that modulate the tumor phenotype.

Tumor-stroma interactions play a critical role in the development of lung squamous carcinoma (LUSC). However, understanding how these dynamic interactions ...