Effects of EGFR overexpression in the generated oral keratinocytes. Equal amounts of protein for OKF6, OKF6-D1, OKF6-dnp53, OKF6-D1/dnp53, OKF6-D1/dnp53/empty, and OKF6-D1/dnp53/EGFR were separated on a 6% SDS/PAGE. The level of EGFR overexpression was compared by subsequent immunoblot analysis using a polyclonal EGFR antibody (1005). EGFR overexpression is indicated as fold increase compared to parental OKF6 cells.