A novel peptide motif binding to and blocking the intracellular activity of the human papillomavirus E6 oncoprotein.
Specific types of human papillomaviruses (HPVs) cause cervical cancer. The viral E6 oncogene is a critical factor for maintaining the malignant phenotype of HPV-positive tumour cells. By yeast two-hybrid screening of a randomised peptide expression library, we isolated linear short peptides, which specifically bind to the HPV16 E6 oncoprotein. Sequence alignments and mutational analyses of the peptides identified a hitherto undiscovered E6-binding motif. Intracellular expression of a peptide containing the novel E6-binding motif resulted in inhibition of colony formation capacity, specifically of HPV16-positive cancer cells. A solubility-optimised variant of the peptide was created, which binds to HPV16 E6 with high affinity. Its intracellular expression efficiently induced apoptosis in HPV16-positive cancer cells. This was linked to restoration of intracellular p53 activities. Thus, this newly identified E6-binding motif could form a novel basis for the development of rational strategies for the treatment of HPV16-positive preneoplastic and neoplastic lesions.
Dymalla
Susanne
S
German Cancer Research Center, Im Neuenheimer Feld, Heidelberg, Germany.
Scheffner
Martin
M
Weber
Elvira
E
Sehr
Peter
P
Lohrey
Claudia
C
Hoppe-Seyler
Felix
F
Hoppe-Seyler
Karin
K
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D000074288:Discs Large Homolog 1 Protein; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D020287:In Situ Nick-End Labeling; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000378:metabolism*; D019151:Peptide Library; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D054875:Ubiquitination
D048868:Adaptor Proteins, Signal Transducing; C513314:DLG1 protein, human; D000074288:Discs Large Homolog 1 Protein; C068651:E6 protein, Human papillomavirus type 16; D008565:Membrane Proteins; D009856:Oncogene Proteins, Viral; D019151:Peptide Library; D010455:Peptides; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D016159:Tumor Suppressor Protein p53; D049452:Green Fluorescent Proteins