Establishment of a visualized mouse orthotopic model of nasopharyngeal carcinoma.

e18048 Background: Nasopharyngeal carcinoma, one of the most common head and neck tumors, is particularly prevalent in Southeast Asia and is characterized by high rates of metastasis and recurrence. Although mouse orthotopic tumor models are commonly employed in studies investigating the mechanisms underlying tumor development and progression, as well as preclinical treatment, currently no such model exists for nasopharyngeal carcinoma. The aim of the current study is to, therefore, establish an orthotopic murine model for nasopharyngeal carcinoma. Methods: To this end, human nasopharyngeal carcinoma C666-1-luc cells, stably expressing the firefly luciferase gene, were injected subcutaneously into the right axilla of BALB/C nude mice. Four weeks later, the resulting subcutaneous tumors were cut into small blocks and grafted into the nasopharynx of immunodeficient BALB/C nude mice to induce tumor formation. Tumor growth was monitored by bioluminescence imaging and small animal magnetic resonance imaging. The histological and immunological antigen expression associated with orthotopic nasopharyngeal carcinoma were analyzed by tissue section analysis and immunohistochemistry (IHC). Results: The tumor formation rate was over 90%. Fluorescence signal detection, micro-magnetic resonance imaging and hematoxylin and eosin staining revealed the successful growth of tumors in the nasopharynx of nude mice. Moreover, IHC analysis detected positive CK, CK5/6, P40 and P63 expression in the mouse orthotopic tumors, which is consistent with the reported antigen expression in the nasopharyngeal tumors of patients. Conclusions: Hence, we successfully established a mouse orthotopic model of nasopharyngeal carcinoma that is highly reproducible, and simple in operation, with low mortality and high tumor formation rates. Moreover, this model facilitates real-time monitoring of tumor growth via in vivo imaging technology, thus, providing a platform for researching nasopharyngeal carcinoma that is more conducive to preclinical research.