p28 is an amphipathic, α-helical, cell penetrating peptide composed of amino acids Leu50-Asp77 of azurin, a redox protein secreted from the opportunistic pathogen pseudomonas aeruginosa. p28 is a post translational, multitarget anticancer agent that preferentially enters a wide variety of solid tumour cells. On entry, p28 binds to both wild-type and mutant p53 protein, inhibiting constitutional morphogenic protein 1 (cop1) mediated ubiquitination and proteasomal degradation of p53, increasing levels of p53 which induce cell cycle arrest at G2/M and causing apoptosis that results in tumour cell shrinkage and death.
Mehta et al (2011) A cell penetrating peptide derived from azurin inhibits angiogenesis and tumor growth by inhibiting phosphorylation of VEGFR-2, FAK and Akt. Angiogenesis 14(3) 355 PMID: 21667138
Yamada et al (2013) p28, a first in class peptide inhibitor of cop1 binding to p53. Br J Cancer. 108(12) 2495 PMID: 23736031
Yaghoubi et al (2020) p28 Bacterial Peptide, as an Anticancer Agent. Front Oncol. 2020 10 1303 PMID: 32850408