Direct in vivo comparison of SuperCD vs YCD vs BCD suicide gene effectiveness. Approximately 1×107 cells of the four cell-lines MH naїve, MH BCD, MH YCD, and MH SuperCD were injected subcutaneously into male ACI rats. After 15 d, prodrug application started with twice weekly ip injections of 283 mg of 5-FC/kg body weight as indicated by black diamonds in panel B. Panel A: Depiction of tumor volumes of all four cell lines in all animals at four time points after implantation. Panel B: Median tumor volume regression lines by analysis of covariance of log tumor volumes. As a result, significant reductions in median tumor volumes under low dose 5-FC application were observed only for the MH SuperCD tumors.