2013 Volume 76 Issue 2 Pages 110-114
It is thought that elucidation of the proliferation potential of oral squamous cell carcinoma (OSCC) will contribute to progress in anticancer therapy. We investigated the proliferation potential of the OSCC cell lines HSC3 and HSC4. 5× 103 cells per well were cultured on a nonadhesive 96-well plate at serum concentrations between 0% and 10%. HSC3 proliferated at a serum concentration of 5%, and showed low level proliferation at 1%. However, no proliferation was seen with a serum concentration of 0%. When HSC4 cells were cultured at concentrations between 1×103 to 2×104 cells per well under serum-free conditions, there was no proliferation at 1×103 cells per well. However, the proliferation increased in a concentration dependent manner up to 2×104 cells per well. Furthermore, when TAPI-2 (Sheddase inhibitor) and DAPT (γ-secretase inhibitor) were added in the HSC4 culture medium, proliferation was reduced only by TAPI-2. Moreover, proliferation was decreased when AG1478, which is an EGFR inhibitor, was added.
These results suggest that HSC4 promotes autonomous proliferation in a serum-free culture based on the autocrine-loop mechanism of the EGFR ligand, which is the growth factor emitted by ectodomain shedding. However, HSC3 had no effect on this system.
