p53 peptides drill for tumors

As the key controller of DNA repair and cell cycle arrest, p53 has long been considered the guardian of the genome, resulting in efforts to develop p53-based cancer therapies. In an article in the Proceedings of the National Academy of Sciences,researchers push the p53 envelope by showing that p53-derived peptides can specifically kill tumor cells through necrosis independent of p53, rather than via the expected p53-specific apoptotic pathway.

Researchers at the State University of New York Downstate Medical Center (Brooklyn, N.Y.) and colleagues fused amino acids 12-26 of p53 to the penetratin polypeptide to enable transport across the cell membrane. The engineered p53 peptides were cytotoxic to cancer cells expressing normal p53 and mutant p53 as well as p53 null cancer cells in a dose responsive manner, but did not alter the growth characteristics of normal cells in culture. Control peptides fused to penetratin had no effect. ...