Effect of Collagen Type I or Human Fibronectin on Imatinib Cytotoxicity in Oral Squamous Cell Carcinoma

Extracellular matrix (ECM) components are critical for all aspects of cell proliferation, adhesion, and morphological alteration. Recent progress has yielded multiple molecular drugs that specifically target gene products which are expressed at high levels in tumor cells. We investigated whether the sensitivity of tumor cells to molecular target drugs could be altered when cells were cultured on surfaces with various coating conditions such as lysine, laminin, Matrigel, collagen type I, and human fibronectin (HFN). This study evaluates the IC50 values of imatinib in oral squamous cell carcinoma (OSCC) cell lines when cells are cultured on plates coated with ECM components such as collagen type I and HFN. Four OSCC cell lines—SQUU-A, SQUU-B, SAS, and NA— are used. Cell proliferation was assessed using WST-8 reagent. Collagen type I and HFN significantly enhanced OSCC cell proliferation compared with control. Imatinib cytotoxicity was demonstrated following culture of OSCCs in culture plates coated with collagen type I or HFN. However, there were no significant changes in imatinib IC50 values between collagen type I and HFN. These results indicate that some molecular target drugs exhibit cancer cell cytotoxicity without being influenced by cell environment factors such as the ECM. These results may aid in the search for molecular target drugs to apply in the clinical chemotherapy of OSCC.