Establishment and characterization of a rabbit oral squamous cell carcinoma cell line as a model for in vivo studies.

The incidence of oral squamous cell carcinoma (SCC) is increasing but the long-term survival rate remains low. An animal model would therefore be helpful for evaluation of new treatment modalities for oral SCC. Hamster is small animal, therefore, the cancer of hamster cheek pouch is not optimal for tumor imaging. The VX2 cell line has been used in many carcinoma-related studies, including oral SCC research, but it is derived from cutaneous tissue and not mucosa. We chemically induced tongue squamous cell carcinoma in rabbits and subsequently established a rabbit squamous cell line. The cells grew in multiple layers without contact inhibition for 60 passages over 2 years and were positive for cytokeratin (CK). Electron microscopy revealed that cells were polygonal with rich microvilli on the surface, and there were desmosomes between cells and bundles of tonofibril beside the cell membrane. The chromosome number ranged from 71 to 272, with a modal value of 145 (12.4%). The cells were transplantable into nude mice subcutaneously or rabbit submucosally and produced carcinomas in all the animals. The cell line should be a useful tool for the study of the biological characteristics of oral SCC, especially tongue SCC.