Tumor angiogenesis is a complex process involving multiple biological mechanisms that enable tumors to grow and spread. Tumors require oxygen and nutrients, which they obtain through blood vessels. The process of tumor angiogenesis is initiated by pro-angiogenic signals, leading to the formation of new blood vessels. Anti-angiogenic therapies, such as antibodies and tyrosine kinase inhibitors, have been developed to block this process, but their effectiveness has been limited due to factors like resistance and alternative angiogenic pathways. Tumor vessels often differ significantly from normal vessels, with heterogeneous structures and functions that complicate treatment. Understanding the molecular and cellular mechanisms of tumor angiogenesis is crucial for developing more effective therapies. Key factors involved in tumor angiogenesis include vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), and angiopoietins. These factors regulate blood vessel formation, maintenance, and function, and their dysregulation contributes to tumor progression. Additionally, other pro-angiogenic factors, such as apelin and chemokines, play roles in tumor angiogenesis. Hypoxia, a common feature of tumors, also contributes to angiogenesis by stabilizing hypoxia-inducible factors (HIFs), which promote the expression of pro-angiogenic genes. Immune cells also contribute to tumor angiogenesis by influencing vascular development and function. Overall, the complexity of tumor angiogenesis presents significant challenges for therapeutic intervention, requiring a deeper understanding of the underlying mechanisms to develop more effective treatments.Tumor angiogenesis is a complex process involving multiple biological mechanisms that enable tumors to grow and spread. Tumors require oxygen and nutrients, which they obtain through blood vessels. The process of tumor angiogenesis is initiated by pro-angiogenic signals, leading to the formation of new blood vessels. Anti-angiogenic therapies, such as antibodies and tyrosine kinase inhibitors, have been developed to block this process, but their effectiveness has been limited due to factors like resistance and alternative angiogenic pathways. Tumor vessels often differ significantly from normal vessels, with heterogeneous structures and functions that complicate treatment. Understanding the molecular and cellular mechanisms of tumor angiogenesis is crucial for developing more effective therapies. Key factors involved in tumor angiogenesis include vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), and angiopoietins. These factors regulate blood vessel formation, maintenance, and function, and their dysregulation contributes to tumor progression. Additionally, other pro-angiogenic factors, such as apelin and chemokines, play roles in tumor angiogenesis. Hypoxia, a common feature of tumors, also contributes to angiogenesis by stabilizing hypoxia-inducible factors (HIFs), which promote the expression of pro-angiogenic genes. Immune cells also contribute to tumor angiogenesis by influencing vascular development and function. Overall, the complexity of tumor angiogenesis presents significant challenges for therapeutic intervention, requiring a deeper understanding of the underlying mechanisms to develop more effective treatments.