There are various similarities between quiescent and senescent cells. Both are two states of stable cell cycle arrest. Quiescent cells temporarily stop their progression through the cell cycle, while senescent cells permanently enter a state of cell cycle arrest. Another similarity is that senescent and quiescent cells exist in the G0 state, which is an inactive state. Additionally, both quiescent and senescent cells remain viable and metabolically active throughout their process in the cell cycle. Quiescent cells have reduced metabolic activity to conserve energy, while senescent cells exhibit metabolic alterations corresponding with SASP (after severe DNA damage). Another similarity is that both types of cells are resistant to apoptosis. Their resistance contributes to the survival of these cells in tissues. Quiescent and senescent cells also both exhibit specific signaling pathways and gene expression pathways. For example, both states are involved in the activation of tumor suppressor genes. It has been demonstrated that p53 suppresses cellular senescence, converting it into a state of quiescence.