Abstract
Our study investigated the histogenesis and biological significance of spindle cell carcinoma (SpCC) by comparing with moderately-well-differentiated squamous cell carcinoma (SCC) cell lines. Snail mRNA expression was readily detectable in the SpCC cell line, while E-cadherin was undetectable. SpCC cells showed lower proliferative and invasive activities than two other SCC cell lines. Culturing under air-liquid interface conditions promoted squamous cell differentiation, whereas fibroblastic differentiation after submerged culture with collagen, suggesting that the microenvironment may be a regulating factor of spindle cell differentiation as well as Snail expression and spindle cell change may not always entail the invasive behavior.