The regulation of tumor angiogenesis by p53-induced degradation of hypoxia-inducible factor 1α (HIF-1α) is a critical mechanism in cancer progression. This study demonstrates that the p53 tumor suppressor gene promotes the degradation of HIF-1α, a key transcription factor involved in hypoxia-induced angiogenesis. In human cancer cells, homozygous deletion of p53 leads to increased HIF-1α levels and enhanced vascular endothelial growth factor (VEGF) expression, which promotes tumor angiogenesis and growth. The study shows that p53 inhibits HIF-1α by targeting it for ubiquitination and proteasomal degradation, thereby suppressing hypoxia-induced angiogenesis. Conversely, loss of p53 function enhances HIF-1α stability and HIF-1-dependent VEGF expression, contributing to the angiogenic switch during tumorigenesis. The findings indicate that p53-mediated inhibition of HIF-1α is a novel mechanism by which p53 suppresses tumor angiogenesis. The study also shows that the E6 oncoprotein of human papillomavirus 16 promotes HIF-1α stability and VEGF expression under hypoxic conditions, further supporting the role of p53 in regulating angiogenesis. Overall, the study highlights the importance of p53 in controlling tumor angiogenesis through its regulation of HIF-1α and VEGF expression.The regulation of tumor angiogenesis by p53-induced degradation of hypoxia-inducible factor 1α (HIF-1α) is a critical mechanism in cancer progression. This study demonstrates that the p53 tumor suppressor gene promotes the degradation of HIF-1α, a key transcription factor involved in hypoxia-induced angiogenesis. In human cancer cells, homozygous deletion of p53 leads to increased HIF-1α levels and enhanced vascular endothelial growth factor (VEGF) expression, which promotes tumor angiogenesis and growth. The study shows that p53 inhibits HIF-1α by targeting it for ubiquitination and proteasomal degradation, thereby suppressing hypoxia-induced angiogenesis. Conversely, loss of p53 function enhances HIF-1α stability and HIF-1-dependent VEGF expression, contributing to the angiogenic switch during tumorigenesis. The findings indicate that p53-mediated inhibition of HIF-1α is a novel mechanism by which p53 suppresses tumor angiogenesis. The study also shows that the E6 oncoprotein of human papillomavirus 16 promotes HIF-1α stability and VEGF expression under hypoxic conditions, further supporting the role of p53 in regulating angiogenesis. Overall, the study highlights the importance of p53 in controlling tumor angiogenesis through its regulation of HIF-1α and VEGF expression.