TSC2 and neoplasm: Although rapamycin and CCI-779 are similar, we have recently shown that rapamycin (8 mg/kg IP 5 days per week) is more effective than CCI-779 (8 mg/kg IP 5 days per week) in the Tsc2-/- subcutaneous tumor model, raising the possibility that the difference is due to rapamycin's higher efficacy as compared to CCI-779 rather than the addition of prolonged weekly maintenance dosing.