The human p27Kip1 C-terminus PIM-1 phosphorylation site- (Thr198) containing sequence is synthesized with an N-terminal Arg octamer/R8-containing sequence to facilitate its use as a cell-permeable, substrate-competitive PIM-1 inhibitor. Reported to completely prevents human prostate carcinoma DU145-derived tumor expansion for up to 17 days (0.5umol/animal on days 0 & 5; intratumoral injection) in mice in vivo when combined with a single Taxol dosage on day zero (60mg/kg; i.p.). Studies using FITC-conjugated R8-T198wt demonstrate that R8-T198wt-induced cell cycle arrest and apoptosis in PIM-1-expressing DU145 cells are direct consequences of inhibition of PIM-1-mediated p27Kip1 Thr198 and Bad Ser112 phosphorylation, respectively.Formula:C₁₁₁H₂₁₁N₅₉O₂₆S₁Sequence:H-Gly-Gly-Gly-Arg-Arg-Arg-Arg-Arg-Arg-Arg-Arg-Gly-Cys-Lys-Lys-Pro-Gly-Leu-Arg-Arg-Arg-Gln-Thr-OHMolecular Weight:2820.4Solubility:DMSO (50mg/ml, clear, colorless solution)Storage and Stability:Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.