The senescence-inhibitory p53 isoform Δ133p53α: enhancing cancer immunotherapy and exploring novel therapeutic approaches for senescence-associated diseases.

Δ133p53α is a naturally occurring isoform of the tumor suppressor protein p53. Δ133p53α functions as a physiological dominant-negative inhibitor of the full-length p53 protein (commonly referred to as p53). Δ133p53α preferentially inhibits p53-mediated cellular senescence, while it does not inhibit, or may even promote, p53-mediated DNA repair. Owing to this selective inhibitory activity that preserves genome stability, Δ133p53α represents a promising target for enhancement in the prevention and treatment of diseases associated with increased senescence of normal cells. These diseases include Alzheimer's and other neurodegenerative diseases, premature aging diseases such as Hutchinson-Gilford progeria syndrome (HGPS), and idiopathic pulmonary fibrosis (IPF). Current cell-based therapies, which are limited by increased cellular senescence, may also benefit from Δ133p53α-mediated improvements. As an initial application of Δ133p53α in improving therapeutic cells, we here introduce Δ133p53α-armored chimeric antigen receptor (CAR)-T cells. Based on our previous and ongoing studies using various types of senescent human cells in vitro, we also discuss the importance of further exploring the therapeutic potentials of Δ133p53α, with particular focus on HGPS and IPF. The development of mouse models facilitates in vivo evaluation of the therapeutic effects of Δ133p53α, potentially leading to future clinical applications.