The study investigates the role of p53 acetylation in tumor suppression, focusing on its effects on cell cycle arrest, apoptosis, and senescence. Researchers generated mice with mutations at key acetylation sites of p53, specifically K117R and KR (K117, K161, K162). While p53K117R cells retained cell cycle arrest and senescence but not apoptosis, p53KR cells lost all three processes. Despite this, neither p53K117R nor p53KR mice developed early-onset tumors, unlike p53-null mice. This suggests that p53's tumor suppression functions beyond cell cycle arrest, apoptosis, and senescence. p53KR retained the ability to regulate energy metabolism and reactive oxygen species (ROS) production, indicating that these unconventional functions are critical for tumor suppression. The findings highlight the importance of acetylation in modulating p53 responses and suggest that p53's metabolic and antioxidant activities are essential for suppressing early-onset spontaneous tumorigenesis. The study challenges the traditional view that p53's tumor suppression relies solely on cell cycle arrest, apoptosis, and senescence.The study investigates the role of p53 acetylation in tumor suppression, focusing on its effects on cell cycle arrest, apoptosis, and senescence. Researchers generated mice with mutations at key acetylation sites of p53, specifically K117R and KR (K117, K161, K162). While p53K117R cells retained cell cycle arrest and senescence but not apoptosis, p53KR cells lost all three processes. Despite this, neither p53K117R nor p53KR mice developed early-onset tumors, unlike p53-null mice. This suggests that p53's tumor suppression functions beyond cell cycle arrest, apoptosis, and senescence. p53KR retained the ability to regulate energy metabolism and reactive oxygen species (ROS) production, indicating that these unconventional functions are critical for tumor suppression. The findings highlight the importance of acetylation in modulating p53 responses and suggest that p53's metabolic and antioxidant activities are essential for suppressing early-onset spontaneous tumorigenesis. The study challenges the traditional view that p53's tumor suppression relies solely on cell cycle arrest, apoptosis, and senescence.