Rapamycin inhibits mTORC1-transduced cell signaling and proliferation of CTCL cells. (A) The CTCL cell lines (left) and mitogen preactivated primary leukemic CTCL cells (right) were cultured for 30 minutes with medium or 100 U of IL-2, as indicated, in the presence of rapamycin at 5nM or its solvent and analyzed for phosphorylation of mTORC1 targets S6rp and 4E-BP1 using phospho-Akt, phospho-ERK1/2, and actin as negative controls. (B) The CTCL cell lines and native, mitogen-primed cells were exposed to medium containing rapamycin at the indicated doses or solvent alone and examined for the apoptotic (B) and proliferative (C) cell rate after 24-hour and 48-hour cultures, respectively. Error bars are SEM.