Role of the Senescence-Associated Factor Dipeptidyl Peptidase 4 in the Pathogenesis of SARS-CoV-2 Infection.

During cellular senescence, persistent growth arrest and changes in protein expression programs are accompanied by a senescence-associated secretory phenotype (SASP). In this study, we detected the upregulation of the SASP-related protein dipeptidyl peptidase 4 (DDP4) in human primary lung cells rendered senescent by exposure to ionizing radiation. DPP4 is an exopeptidase that plays a crucial role in the cleavage of various proteins, resulting in the loss of N-terminal dipeptides and proinflammatory effects.

It's About Time: Advances in Understanding the Circadian Regulation of DNA Damage and Repair in Carcinogenesis and Cancer Treatment Outcomes.

The circadian rhythm is established by a coordinated network of peripheral clocks interlocked and regulated by a central pacemaker. This network is maintained by the rhythmic expression of core clock genes, which in turn generate oscillatory expression patterns of different sets of target proteins in a tissue-specific manner. Precise regulation of biological processes driven by the body's circadian network in response to periodic changes in the environment determines healthy life.