Antitumor effect of CCI-779. Mice (8-14 per group) challenged subcutaneously with OPM-2 (A) or 8226 (B) cells. When tumor size reached 200 mm³, mice were randomly assigned to receive vehicle alone or varying doses of CCI-779 intraperitoneally for 10 days, as described in “Materials and methods.” Results are tumor size (mean ± SEM). Solid bars on x-axis denote days of intraperitoneal treatment.