A p21(Waf1/Cip1)carboxyl-terminal peptide exhibited cyclin-dependent kinase-inhibitory activity and cytotoxicity when introduced into human cells.
In the present study, we report the cyclin-dependent kinase (Cdk)-inhibitory activity of a series of p21waf1/cip1 (p21) peptide fragments spanning the whole protein against the cyclin D1/Cdk4 and cyclin E/Cdk2 enzymes. The most potent p21 peptide tested in our initial peptide series, designated W10, spanned amino acids 139 to 164, a region of p21 that has been found independently to bind to proliferating cell nuclear antigen and also to inhibit Cdk activity. We go on to report the importance of putative beta-strand and 3(10)-helix motifs in the W10 peptide for cyclin-dependent kinase-inhibitory activity. We also describe the cellular activity of W10 and derivatives that were chemically linked to an antennapedia peptide, the latter segment acting as a cell membrane carrier. We found that the W10AP peptide exhibited growth inhibition that resulted from necrosis in human lymphoma CA46 cells. Furthermore, regions in the W10 peptide responsible for Cdk-inhibition were also important for the degree of this cellular activity. These studies provide insights that may eventually, through further design, yield agents for the therapy of cancer.
Laboratory of Molecular Pharmacology, National Cancer Institute, NIH, Bethesda, Maryland 20892-4255, USA.
M
M
Mutoh
F D
FD
Lung
Y Q
YQ
Long
P P
PP
Roller
R S
RS
Sikorski
P M
PM
O'Connor
D000595:Amino Acid Sequence; D051943:Antennapedia Homeodomain Protein; D002051:Burkitt Lymphoma / Q000201:enzymology* / Q000473:pathology; D002462:Cell Membrane / Q000378:metabolism; D019938:Cyclin D1 / Q000037:antagonists & inhibitors*; D019927:Cyclin E / Q000037:antagonists & inhibitors*; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D005434:Flow Cytometry; D018398:Homeodomain Proteins / Q000494:pharmacology; D006801:Humans; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009336:Necrosis; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors*; D009687:Nuclear Proteins; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013329:Structure-Activity Relationship; D014157:Transcription Factors; D014407:Tumor Cells, Cultured / Q000187:drug effects
D051943:Antennapedia Homeodomain Protein; C493956:CDKN1A protein, human; D019927:Cyclin E; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D018398:Homeodomain Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D010446:Peptide Fragments; D018809:Proliferating Cell Nuclear Antigen; D014157:Transcription Factors; D019938:Cyclin D1