β-Galactosidase-Activatable Nile Blue-Based NIR Senoprobe for the Real-Time Detection of Cellular Senescence.

Cellular senescence is a stable cell cycle arrest in response to stress or other damage stimuli to maintain tissue homeostasis. However, the accumulation of senescent cells can lead to the progression of various senescence-related disorders. In this paper, we describe the development of a β-galactosidase-activatable near-infrared (NIR) senoprobe, , for the detection of senescent cells based on the use of the FDA-approved Nile blue () fluorophore. was validated in chemotherapeutic-induced senescence cancer models using SK-Mel 103 and 4T1 cell lines. monitoring of cellular senescence was evaluated in orthotopic triple-negative breast cancer-bearing mice treated with palbociclib to induce senescence. In all cases, exhibited a selective tracking of senescent cells mainly ascribed to the overexpressed β-galactosidase enzyme responsible for hydrolyzing the probe generating the highly emissive fluorophore. In this way, has proven to be a qualitative, rapid, and minimally invasive probe that allows the direct detection of senescent cells .