PNC-27, a Chimeric p53-Penetratin Peptide Binds to HDM-2 in a p53 Peptide-like Structure, Induces Selective Membrane-Pore Formation and Leads to Cancer Cell Lysis
Ehsan Sarafraz-Yazdi,
Stephen Mumin,
Diana Cheung,
Daniel Fridman,
Brian Lin,
Lawrence Wong,
Ramon Rosal,
Rebecca Rudolph,
Matthew Frenkel,
Anusha Thadi,
William F. Morano,
Wilbur B. Bowne,
Matthew R. Pincus,
Josef Michl
Affiliations
Ehsan Sarafraz-Yazdi
NomoCan Pharmaceuticals LLC, New York Blood Center, 310 East 67th Street, New York, NY 10065, USA
Stephen Mumin
NomoCan Pharmaceuticals LLC, New York Blood Center, 310 East 67th Street, New York, NY 10065, USA
Diana Cheung
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
Daniel Fridman
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
Brian Lin
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
Lawrence Wong
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
Ramon Rosal
Department of Health of New York City, 455 First Avenune, New York, NY 10016, USA
Rebecca Rudolph
Microscopy and Imaging Department, American Museum of Natural History, Central Park West and 79th Street, New York, NY 10024, USA
Matthew Frenkel
Microscopy and Imaging Department, American Museum of Natural History, Central Park West and 79th Street, New York, NY 10024, USA
Anusha Thadi
Department of Surgery, Drexel University College of Medicine, 230 North Broad Street, Philadelphia, PA 19102, USA
William F. Morano
Department of Surgery, Drexel University College of Medicine, 230 North Broad Street, Philadelphia, PA 19102, USA
Wilbur B. Bowne
Department of Surgery, Drexel University College of Medicine, 230 North Broad Street, Philadelphia, PA 19102, USA
Matthew R. Pincus
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
Josef Michl
Department of Pathology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
PNC-27, a 32-residue peptide that contains an HDM-2 binding domain and a cell-penetrating peptide (CPP) leader sequence kills cancer, but not normal, cells by binding to HDM-2 associated with the plasma membrane and induces the formation of pores causing tumor cell lysis and necrosis. Conformational energy calculations on the structure of PNC-27 bound to HDM-2 suggest that 1:1 complexes form between PNC-27 and HDM-2 with the leader sequence pointing away from the complex. Immuno-scanning electron microscopy was carried out with cancer cells treated with PNC-27 and decorated with an anti-PNC-27 antibody coupled to 6 nm gold particles and an anti-HDM-2 antibody linked to 15 nm gold particles. We found multiple 6 nm- and 15 nm-labeled gold particles in approximately 1:1 ratios in layered ring-shaped structures in the pores near the cell surface suggesting that these complexes are important to the pore structure. No pores formed in the control, PNC-27-treated untransformed fibroblasts. Based on the theoretical and immuno-EM studies, we propose that the pores are lined by PNC-27 bound to HDM-2 at the membrane surface with the PNC-27 leader sequence lining the pores or by PNC-27 bound to HDM-2.
