Characterization of a spontaneously arising murine squamous cell carcinoma (SCC VII) as a prerequisite for head and neck cancer immunotherapy

Background. To develop novel therapeutic approaches for patients with head and neck malignancies, poorly immunogenic murine models of squamous cell carcinoma (SCC) need to be defined. Methods. The phenotype, growth characteristics, and responsiveness to tumor-specific T-cell transfer of a spontaneously arising murine SCC (SCC VII) were characterized. Results. SCC VII expresses major histocompatibility complex (MHC) class I molecules yet is resistant to tumor-specific T-cell killing and relatively insensitive to killing mediated by lymphokine-activated killer (LAK) cells. Intradermal tumors are reproducibly established after vaccination of 5 × 10⁴ cells, and systemic micrometastases are apparent after intravenous administration of 2.5 × 10⁴ cells. Immunotherapy of 3-day lung metastases using tumor-specific T cells and systemic interleukin-2 (IL-2) was ineffective in reducing the number of metastases in vivo. Conclusions. SCC VII is a poorly immunogenic murine squamous cell cancer, which represents an ideal model for preclinical testing of immunotherapeutic approaches for patients with SCC of the upper aerodigestive tract.