Fig. 1.

Senescence‐associated secretory phenotype (SASP) exhibits both tumour‐promoting and tumour‐suppressing roles. Senescent cells secrete a number of factors. including growth factors, MMPs, interleukins, chemokines and cytokines, which can play many complex roles in the tumour microenvironment (TME). The red arrows highlight tumour‐promoting roles, including increases in epithelial‐to‐mesenchymal (EMT) initiation, cancer cell stemness, invasion and metastasis, angiogenesis, immunosuppression, fibroblast activation and therapy resistance. The green arrows highlight tumour‐suppressive roles of SASP, including cell cycle arrest and an increase in immune surveillance resulting in improved cancer cell clearing by the immune system.