All animal procedures were performed in accordance with an approved institutional animal care and use committee (IACUC) protocol of the University of Colorado Denver (protocol # 00250).
1. Tumor Cell Culture
NOTE: B4B8 and LY2 cell lines were used to generate orthotopic HNSCC tumors: B4B8 tumor cells were derived from carcinogen-transformed mucosal keratinocytes (from BALB/C mice)11. LY2 tumor cells were derived from lymph node...

<ol>
	<li>Chaturvedi, A. K., 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=Worldwide+trends+in+incidence+rates+for+oral+cavity+and+oropharyngeal+cancers.">Worldwide trends in incidence rates for oral cavity and oropharyngeal cancers.</a> Journal of Clinical Oncology. 31 (36), 4550-4559 (2013).</li><li>Ang, K. K., Sturgis, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+papillomavirus+as+a+marker+of+the+natural+history+and+response+to+therapy+of+head+and+neck+squamous+cell+carcinoma.">Human papillomavirus as a marker of the natural history and response to therapy of head and neck squamous cell carcinoma.</a> Seminars in Radiation Oncology. 22 (2), 128-142 (2012).</li><li>Amin, M. B., 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=The+Eighth+Edition+AJCC+Cancer+Staging+Manual:+Continuing+to+build+a+bridge+from+a+population-based+to+a+more+&amp;#34;personalized&amp;#34;+approach+to+cancer+staging.">The Eighth Edition AJCC Cancer Staging Manual: Continuing to build a bridge from a population-based to a more &amp;#34;personalized&amp;#34; approach to cancer staging.</a> CA: A Cancer Journal for Clinicians. 67 (2), 93-99 (2017).</li><li>Salley, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+carcinogenesis+in+the+cheek+pouch+of+the+Syrian+hamster.">Experimental carcinogenesis in the cheek pouch of the Syrian hamster.</a> Journal of Dental Research. 33 (2), 253-262 (1954).</li><li>Morris, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+influencing+experimental+carcinogensis+in+the+hamster+cheek+pouch.">Factors influencing experimental carcinogensis in the hamster cheek pouch.</a> Journal of Dental Research. 40, 3-15 (1961).</li><li>MacDonald, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+epithelial+dysplasia+in+hamster+cheek+pouch+carcinogenesis+and+human+oral+mucosa.">Comparison of epithelial dysplasia in hamster cheek pouch carcinogenesis and human oral mucosa.</a> Journal of Oral Pathology &amp; Medicine. 10 (3), 186-191 (1981).</li><li>Hawkins, B. 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=4NQO+carcinogenesis:+a+mouse+model+of+oral+cavity+squamous+cell+carcinoma.">4NQO carcinogenesis: a mouse model of oral cavity squamous cell carcinoma.</a> Head &amp; Neck. 16 (5), 424-432 (1994).</li><li>Tang, X. H., Knudsen, B., Bemis, D., Tickoo, S., Gudas, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oral+cavity+and+esophageal+carcinogenesis+modeled+in+carcinogen-treated+mice.">Oral cavity and esophageal carcinogenesis modeled in carcinogen-treated mice.</a> Clinical Cancer Research. 10 (1 Pt 1), 301-313 (2004).</li><li>Vered, M., Yarom, N., Dayan, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=4NQO+oral+carcinogenesis:+animal+models,+molecular+markers+and+future+expectations.">4NQO oral carcinogenesis: animal models, molecular markers and future expectations.</a> Oral Oncology. 41 (4), 337-339 (2005).</li><li>Bornstein, S., 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=Smad4+loss+in+mice+causes+spontaneous+head+and+neck+cancer+with+increased+genomic+instability+and+inflammation.">Smad4 loss in mice causes spontaneous head and neck cancer with increased genomic instability and inflammation.</a> Journal of Clinical Investigation. 119 (11), 3408-3419 (2009).</li><li>Thomas, G. R., Chen, Z., Oechsli, M. N., Hendler, F. J., Van Waes, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decreased+expression+of+CD80+is+a+marker+for+increased+tumorigenicity+in+a+new+murine+model+of+oral+squamous-cell+carcinoma.">Decreased expression of CD80 is a marker for increased tumorigenicity in a new murine model of oral squamous-cell carcinoma.</a> International Journal of Cancer. 82 (3), 377-384 (1999).</li><li>Yuspa, S. H., Hawley-Nelson, P., Koehler, B., Stanley, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+survey+of+transformation+markers+in+differentiating+epidermal+cell+lines+in+culture.">A survey of transformation markers in differentiating epidermal cell lines in culture.</a> Cancer Research. 40 (12), 4694-4703 (1980).</li><li>Chen, Z., Smith, C. W., Kiel, D., Van Waes, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metastatic+variants+derived+following+in+vivo+tumor+progression+of+an+in+vitro+transformed+squamous+cell+carcinoma+line+acquire+a+differential+growth+advantage+requiring+tumor-host+interaction.">Metastatic variants derived following in vivo tumor progression of an in vitro transformed squamous cell carcinoma line acquire a differential growth advantage requiring tumor-host interaction.</a> Clinical &amp; Experimental Metastasis. 15 (5), 527-537 (1997).</li><li>Euhus, D. M., Hudd, C., LaRegina, M. C., Johnson, F. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+measurement+in+the+nude+mouse.">Tumor measurement in the nude mouse.</a> Journal of Surgical Oncology. 31 (4), 229-234 (1986).</li><li>Tomayko, M. M., Reynolds, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+subcutaneous+tumor+size+in+athymic+(nude)+mice.">Determination of subcutaneous tumor size in athymic (nude) mice.</a> Cancer Chemotherapy and Pharmacology. 24 (3), 148-154 (1989).</li><li>Yushkevich, P. 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=User-guided+3D+active+contour+segmentation+of+anatomical+structures:+significantly+improved+efficiency+and+reliability.">User-guided 3D active contour segmentation of anatomical structures: significantly improved efficiency and reliability.</a> NeuroImage. 31 (3), 1116-1128 (2006).</li><li>Dutta, S., 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=The+relationship+between+tumour+necrosis,+tumour+proliferation,+local+and+systemic+inflammation,+microvessel+density+and+survival+in+patients+undergoing+potentially+curative+resection+of+oesophageal+adenocarcinoma.">The relationship between tumour necrosis, tumour proliferation, local and systemic inflammation, microvessel density and survival in patients undergoing potentially curative resection of oesophageal adenocarcinoma.</a> Britisch Journal of Cancer. 106 (4), 702-710 (2012).</li><li>Li, H., 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=Genomic+analysis+of+head+and+neck+squamous+cell+carcinoma+cell+lines+and+human+tumors:+a+rational+approach+to+preclinical+model+selection.">Genomic analysis of head and neck squamous cell carcinoma cell lines and human tumors: a rational approach to preclinical model selection.</a> Molecular Cancer Research. 12 (4), 571-582 (2014).</li><li>Walsh, N. C., 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=Humanized+Mouse+Models+of+Clinical+Disease.">Humanized Mouse Models of Clinical Disease.</a> Annual Review of Pathology. 12, 187-215 (2017).</li><li>Oweida, 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=Ionizing+radiation+sensitizes+tumors+to+PD-L1+immune+checkpoint+blockade+in+orthotopic+murine+head+and+neck+squamous+cell+carcinoma.">Ionizing radiation sensitizes tumors to PD-L1 immune checkpoint blockade in orthotopic murine head and neck squamous cell carcinoma.</a> OncoImmunology. 6 (10), e1356153 (2017).</li><li>Ferris, R., 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=Further+evaluations+of+nivolumab+(nivo)+versus+investigator&#8217;s+choice+(IC)+chemotherapy+for+recurrent+or+metastatic+(R/M)+squamous+cell+carcinoma+of+the+head+and+neck+(SCCHN):+CheckMate+141.">Further evaluations of nivolumab (nivo) versus investigator&#8217;s choice (IC) chemotherapy for recurrent or metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN): CheckMate 141.</a> Journal of Clinical Oncology. 34, (2016).</li><li>Ferris, R. 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=Nivolumab+for+Recurrent+Squamous-Cell+Carcinoma+of+the+Head+and+Neck.">Nivolumab for Recurrent Squamous-Cell Carcinoma of the Head and Neck.</a> The New England Journal of Medicine. 375 (19), 1856-1867 (2016).</li><li>Harrington, K. 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=Nivolumab+versus+standard,+single-agent+therapy+of+investigator's+choice+in+recurrent+or+metastatic+squamous+cell+carcinoma+of+the+head+and+neck+(CheckMate+141):+health-related+quality-of-life+results+from+a+randomised,+phase+3+trial.">Nivolumab versus standard, single-agent therapy of investigator's choice in recurrent or metastatic squamous cell carcinoma of the head and neck (CheckMate 141): health-related quality-of-life results from a randomised, phase 3 trial.</a> The Lancet Oncology. 18 (8), 1104-1115 (2017).</li><li>Kiyota, N., 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=A+randomized,+open-label,+Phase+III+clinical+trial+of+nivolumab+vs.+therapy+of+investigator's+choice+in+recurrent+squamous+cell+carcinoma+of+the+head+and+neck:+A+subanalysis+of+Asian+patients+versus+the+global+population+in+checkmate+141.">A randomized, open-label, Phase III clinical trial of nivolumab vs. therapy of investigator's choice in recurrent squamous cell carcinoma of the head and neck: A subanalysis of Asian patients versus the global population in checkmate 141.</a> Oral Oncology. 73, 138-146 (2017).</li><li>Ling, D. C., Bakkenist, C. J., Ferris, R. L., Clump, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+Immunotherapy+in+Head+and+Neck+Cancer.">Role of Immunotherapy in Head and Neck Cancer.</a> Seminars in Radiation Oncology. 28 (1), 12-16 (2018).</li><li>Perri, 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=Radioresistance+in+head+and+neck+squamous+cell+carcinoma:+Biological+bases+and+therapeutic+implications.">Radioresistance in head and neck squamous cell carcinoma: Biological bases and therapeutic implications.</a> Head &amp; Neck. 37 (5), 763-770 (2015).</li><li>Yamamoto, V. N., Thylur, D. S., Bauschard, M., Schmale, I., Sinha, U. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overcoming+radioresistance+in+head+and+neck+squamous+cell+carcinoma.">Overcoming radioresistance in head and neck squamous cell carcinoma.</a> Oral Oncology. 63, 44-51 (2016).</li><li>Bonner, J. 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=Radiotherapy+plus+cetuximab+for+locoregionally+advanced+head+and+neck+cancer:+5-year+survival+data+from+a+phase+3+randomised+trial,+and+relation+between+cetuximab-induced+rash+and+survival.">Radiotherapy plus cetuximab for locoregionally advanced head and neck cancer: 5-year survival data from a phase 3 randomised trial, and relation between cetuximab-induced rash and survival.</a> The Lancet Oncology. 11 (1), 21-28 (2010).</li><li>Bhatia, S., 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=Inhibition+of+EphB4-Ephrin-B2+Signaling+Enhances+Response+to+Cetuximab-Radiation+Therapy+in+Head+and+Neck+Cancers.">Inhibition of EphB4-Ephrin-B2 Signaling Enhances Response to Cetuximab-Radiation Therapy in Head and Neck Cancers.</a> Clinical Cancer Research. 24 (18), 4539-4550 (2018).</li><li>Bhatia, S., 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=Enhancing+radiosensitization+in+EphB4+receptor-expressing+Head+and+Neck+Squamous+Cell+Carcinomas.">Enhancing radiosensitization in EphB4 receptor-expressing Head and Neck Squamous Cell Carcinomas.</a> Scientific Reports. 6, 38792 (2016).</li><li>Tang, C., 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=Combining+radiation+and+immunotherapy:+a+new+systemic+therapy+for+solid+tumors?.">Combining radiation and immunotherapy: a new systemic therapy for solid tumors?.</a> Cancer Immunology Research. 2 (9), 831-838 (2014).</li><li>Oweida, 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=Resistance+to+radiotherapy+and+PD-L1+blockade+is+mediated+by+TIM-3+upregulation+and+regulatory+T-cell+infiltration.">Resistance to radiotherapy and PD-L1 blockade is mediated by TIM-3 upregulation and regulatory T-cell infiltration.</a> Clinical Cancer Research. , (2018).</li></ol>

Rigorous analysis and characterization of the tumor microenvironment represent an important strategy for understanding mechanisms of tumor development, progression, and metastases and for the development of effective therapies. Head and neck cancer is a complex disease that can originate from multiple anatomical sites within the head and neck region. A major impediment to understanding disease mechanisms and improving therapy has been a lack of murine mouse cell lines that resemble the aggressive and metastatic nature of...

HNSCC is the fifth most common malignancy globally, with over 600,000 patients diagnosed annually1. Despite aggressive treatment involving chemotherapy and radiotherapy (RT), the overall survival (OS) rate for HNSCC patients without human papillomavirus (HPV) infection remains below 50% after 5 years2. This is largely attributed to a highly complex tumor microenvironment as tumors can originate from several distinct anatomical sites within the head and neck region, including the buccal mucosa, tongue, floor of the mouth, nasal cavity, oral cavity, pharynx, oropharynx, and hypopharynx. In addition, the head and neck region is highly vascularized and contains nearly half of all lymph nodes in the body3. A majority of studies investigating head and neck tumor biology rely on tumor models in the flank region. Such models can offer insight into tumor-intrinsic mechanisms, but the lack of the native head and neck microenvironment can significantly impact the translational potential of such findings. One method that has been used to induce oral tumors is through exposure to the carcinogen 9,10-dimethyl-1,2-benzanthracene (DMBA)4. However, this method is associated with a lengthy process, induces tumors in rats and hamsters but not in mice, and the resulting tumors do not possess many of the histological features of differentiated SCCs5,6. The introduction of the carcinogen4-nitroquinoline 1-oxide (4-NQO), a water-soluble quinolone derivative, resulted in mouse oral tumors when applied orally but also suffered from long exposure times (16 weeks) and a limited take rate within and between batches of mice7,8,9. In order to develop clinically relevant models, several groups utilized genetically engineered models involving the manipulation of driver oncogenes or tumor suppressor genes, including TP53, TGFB, KRAS, HRAS, and SMAD410. These models can offer insight into tumors with known driver genes but do not recapitulate the complex heterogeneity of human HNSCCs.
In this work, we demonstrate the feasibility of performing an intramucosal inoculation of squamous cell carcinoma cells in mice. Inoculated cells develop into aggressive tumors within 1 week of injection. Similar to human HNSCCs, the tumors metastasize to the regional lymph nodes. We characterize histological and clinical features of the disease and provide insight into the tumor immune microenvironment. We propose that this orthotopic model of HNSCC has applications in cancer biology, tumor immunology, and preclinical studies. Mechanisms of immune evasion, tumor progression, treatment resistance, and metastases represent areas of clinical significance that can be addressed using the proposed model.

<table border="0" cellpadding="0" cellspacing="0" style="width:991px;" width="991">
	<tbody>
		<tr height="40">
			<td height="40" style="height:40px;width:327px;">Collagenase III</td>
			<td style="width:217px;">Worthington Biochemical Corp.</td>
			<td style="width:120px;">LS004183</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">DNase I</td>
			<td>Worthington Biochemical Corp.</td>
			<td>LS006328</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Fc Block (CD16/32)</td>
			<td>BD Biosciences</td>
			<td>553141</td>
			<td style="width:327px;">&#160;Clone 2.4G2&#160;</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Flow Cytometry Staining Buffer</td>
			<td>eBioscience</td>
			<td>00-4222-26</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">HBSS</td>
			<td>ThermoFisher Scientific</td>
			<td>14175079</td>
			<td style="width:327px;">no calcium, no magnesium, no pheno red</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Helois mass cytometer</td>
			<td>Fluidigm</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Matrigel membrane matrix</td>
			<td>Corning&#160;</td>
			<td>CB-40234B</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">MRI Scanner</td>
			<td>Bruker</td>
			<td>NA</td>
			<td>7.4 Tesla</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">RBC lysis buffer</td>
			<td>BioLegend</td>
			<td>420301</td>
			<td style="width:327px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Trypsin inhibitor</td>
			<td>Worthington Biochemical Corp.</td>
			<td>LS002830</td>
			<td style="width:327px;"></td>
		</tr>
	</tbody>
</table>

intramucosal inoculation of squamous cell carcinoma cells in mice for tumor immune profiling and treatment response assessment

Head and neck squamous cell carcinoma (HNSCC) is a debilitating and deadly disease with a high prevalence of recurrence and treatment failure. To develop better therapeutic strategies, understanding tumor microenvironmental factors that contribute to the treatment resistance is important. A major impediment to understanding disease mechanisms and improving therapy has been a lack of murine cell lines that resemble the aggressive and metastatic nature of human HNSCCs. Furthermore, a majority of murine models employ subcutaneous implantations of tumors which lack important physiological features of the head and neck region, including high vascular density, extensive lymphatic vasculature, and resident mucosal flora. The purpose of this study is to develop and characterize an orthotopic model of HNSCC. We employ two genetically distinct murine cell lines and established tumors in the buccal mucosa of mice. We optimize collagenase-based tumor digestion methods for the optimal recovery of single cells from established tumors. The data presented here show that mice develop highly vascularized tumors that metastasize to regional lymph nodes. Single-cell multiparametric mass cytometry analysis shows the presence of diverse immune populations with myeloid cells representing the majority of all immune cells. The model proposed in this study has applications in cancer biology, tumor immunology, and preclinical development of novel therapeutics. The resemblance of the orthotopic model to clinical features of human disease will provide a tool for enhanced translation and improved patient outcomes.

The in vitro assessment of LY2 and B4B8 cell proliferation showed that both cell lines have similar doubling times (21 h and 23 h, respectively). In vivo, both cell lines formed a single, visible, and palpable mass within 1 week of inoculation (Figure 1A). In mice bearing LY2 tumors, the jaw was displaced by 3 weeks due to tumor burden (Figure 1A). Control mice that did not receive tumor cells did not develop tumors as anticipate...

Watch this Scientific Journal Video about Intramucosal Inoculation of Squamous Cell Carcinoma Cells in Mice for Tumor Immune Profiling and Treatment Response Assessment at JoVE.com

Intramucosal Inoculation of Squamous Cell Carcinoma Cells in Mice for Tumor Immune Profiling and Treatment Response Assessment

Here we present a reproducible method for developing an orthotopic murine model of head and neck squamous cell carcinoma. Tumors demonstrate clinically relevant histopathological features of the disease, including necrosis, poor differentiation, nodal metastases, and immune infiltration. Tumor-bearing mice develop clinically relevant symptoms including dysphagia, jaw displacement, and weight loss.

Head and neck squamous cell carcinoma (HNSCC) is a debilitating and deadly disease with a high prevalence of recurrence and treatment failure. To develop ...

Cancers of the head and neck region are becoming increasingly prevalent. Yet, there's limited understanding of the tumor microenvironment and the mechanisms of treatment resistance in this region. This technique can be used to recapitulate the native microenvironment of head/neck tumors in an accessible manner and produces clinical manifestations similar to those seen in humans.When the tumor cell culture has reached 70%confluency, wash the cells three times with cold PBS per wash and attach the cells with enough 0.25%trypsin to cover the bottom surface of the culture flask. After three to four minutes in the cell culture incubator, confirm detachment under a light microscope and neutralize the trypsin with 12 milliliters of DMEM F12 medium, supplemented with fetal bovine serum. Transfer the cell suspension into a 50 milliliter conical tube and mix the cells three to four times by inversion.Then collect the cells by centrifugation and re-suspend the pellet in serum and antibiotic-free DMEM at a one times 10 to the sixth tumor cells per 50 microliters of medium concentration on ice. Immediately before the injection, mix the cells at a one to one tumor cells suspension to basement membrane matrix ratio on ice. Load one 0.5 milliliter syringe equipped with a 23-gauge needle with 100 microliters of cells per recipient animal.Place the syringes on ice and confirm a lack of response to toe pinch in an anesthetized mouse. Next, insert the needle into the right or left buccal region through the available open space on either side of the mouth keeping the syringe parallel to the buccal region while it is inside the oral cavity to facilitate injection of the full 100 microliter volume of the cell basement membrane matrix suspension over a period of five seconds. Keep the syringe in place for an additional five seconds to ensure that all of the material has been injected before withdrawing the syringe gently.The tumors will become grossly visible in about a week. One week after the injection, use calipers to measure the length and width of each tumor to determine the tumor volume one to two times a week. And measure the weight of each animal to assess the effects of the tumor growth on feeding.At the appropriate experimental endpoint, use sharp scissors and blunt forceps to make a skin incision through the midline in the neck. And insert the scissors gently under the skin covering the tumor to create air pockets by pushing the scissors across and into the skin. Once the skin is sufficiently detached from the tumor, excise the draining lymph nodes to avoid having the tumor tissue confounded by the presence of lymph tissue and cut through the borders of the tumor until the entire volume is detached.To process the tumor for downstream analysis, cut the tumor into one to two millimeter sized pieces and place the pieces into a 50 milliliter conical tube containing collagenase three, DNAs one, and trypsin inhibitor. After incubating the tumor pieces at 37 degrees Celsius for 30 minutes, with shaking every 10 minutes, add 20 milliliters of HBSS to the tube and pass the suspension containing the tumor pieces through a 70 micrometer pour nylon strainer. Use a five milliliter syringe plunger to mash the tumor pieces in the strainer and add an additional 10 milliliters of HBSS through the strainer.Spin down the cells by centrifugation. Re-suspend the pellet in two to three milliliters of red blood cell lysis buffer with rigorous pipetting, neutralizing the lysis with 20 milliliters of fresh HBSS after two minutes at room temperature. Then re-suspend the cells in an additional 20 milliliters of HBSS for another centrifugation and strain the cells through a 40 micrometer pour filter to remove any final debris from the tumor cell suspension.LY2 tumors grow at a higher rate, compared to B4B8 tumors. And mice that exhibit jaw displacement rapidly develop weight loss, due to dysphagia. The median survival in LY2 mice is also less than half that observed for B4B8 tumor-bearing mice.Magnetic resonance imaging of tumor-bearing mice shows well-demarcated tumors extending into the inner layer of the buccal mucosa, but not into the tongue or other nearby organs. Histologic examination indicates that all LY2 tumor-bearing mice develop poorly differentiated squamous cell carcinoma, while mice bearing B4B8 tumors develop moderately differentiated squamous cell carcinoma. All LY2 tumor bearing mice also have histologically confirmed necrosis, with the majority demonstrating moderate to severe necrosis.In this representative experiment, a LY2 tumor was harvested and processed three weeks after buccal region tumor cell injection, as demonstrated. CD45-positive immune cells represented 7.3%of the total tumor cell population. CD11b-positive myeloid cells represented 37.8%of all of the CD45-positive cells, the majority of which were determined to be F480-positive macrophages, with small populations of neutrophils and myeloid-derived suppressor cells also observed.T cells comprised 15.9%of the CD45-positive immune cell population, 53.4%of which were CD4-positive FoxP3-positive regulatory T cells. Natural killer cells comprised less than 2%of all all of the CD45-positive cells. It is important to practice injection in order to develop confidence and comfort in holding the needle and the recipient mouse and in exposing the mouth of the animal.Once the procedure has been successfully performed, experiments involving the assessment of tumor response to therapy or assessment of the tumor intrinsic and microenvironmental factors can be performed. This technique has paved the way in designing an investigator-initiated clinical trial, assessing the effects of combining radiotherapy with anti-PL1 therapy in head and neck cancer patients.

intramucosal-inoculation-squamous-cell-carcinoma-cells-mice-for-tumor

Research

JoVE Journal

Cancer Research

11.3K ビュー.  University of Colorado Denver - Anschutz Medical Campus. 頭頸部の癌は、ますます普及しつつある。しかし、この地域の腫瘍微小環境と治療抵抗のメカニズムに関する理解は限られています。この技術は、アクセス可能な方法で頭頸部腫瘍のネイティブ微小環境を再現するために使用することができ、ヒトに見られるものと同様の臨床症状を生成する。腫瘍細胞培養が70%の合流度に達したら、細胞を1回の洗浄で冷たいPBSで...