Senescence is a cellular stress response triggered by diverse stressors, including oncogene activation, where it serves as a bona-fide tumour suppressor mechanism. Senescence can be transmitted to neighbouring cells, known as paracrine secondary senescence. Secondary senescence was initially described as a paracrine mechanism, but recent evidence suggests a more complex scenario involving juxtacrine communication between cells. In addition, single-cell studies described differences between primary and secondary senescent end-points, which have thus far not been considered functionally distinct. Here we discuss emerging concepts in senescence transmission and heterogeneity in primary and secondary senescence on a cellular and organ level.
- CCAAT-Enhancer-Binding Protein-beta/metabolism
- Cellular Senescence/physiology
- Jagged-1 Protein/metabolism
- Paracrine Communication
- Receptors, Notch/metabolism
- Signal Transduction
- Transforming Growth Factor beta/metabolism