[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [General pathology](https://durgical.com/en/general-pathology/) › [Neoplasia](https://durgical.com/en/general-pathology/#a-neoplasia) › Tumour angiogenesis [General pathology](https://durgical.com/en/general-pathology/) · [Neoplasia](https://durgical.com/en/general-pathology/#a-neoplasia) # Tumour angiogenesis - Mechanism A tumour cannot grow beyond a tiny size without its own blood vessels, so it learns to order new ones, mainly through VEGF. Updated 2026-11-01 ## Key points - Hypoxia stabilises HIF-1 alpha, which induces VEGF. - VHL normally degrades HIF: VHL loss makes clear cell renal carcinoma highly vascular. - RAS and MYC increase VEGF; p53 induces the inhibitor thrombospondin-1, so p53 loss favours angiogenesis. - Tumour vessels are leaky and chaotic: they cause bleeding, oedema and easy entry of tumour cells into the blood. - Anti-VEGF drugs can cause hypertension, bleeding, thrombosis, proteinuria and poor wound healing. ## What it is Oxygen and nutrients diffuse only a short distance, so a tumour larger than a few millimetres needs new vessels. The angiogenic switch occurs when pro-angiogenic signals (VEGF, FGF) outweigh inhibitors (thrombospondin-1, angiostatin), driven by hypoxia through HIF and by oncogenes. Tumour vessels are leaky, tortuous and disorganised, which helps metastasis and makes them a target for anti-VEGF therapy. ## Structure - Glioblastoma shows microvascular (glomeruloid) proliferation and necrosis with pseudopalisading tumour cells. - Clear cell renal carcinoma has a delicate, rich network of thin vessels around nests of clear cells. - Hepatocellular carcinoma has arterialised blood supply, which explains its imaging pattern. ## Step by step - As a tumour grows, cells far from vessels become hypoxic. - Hypoxia stabilises HIF-1 alpha, which enters the nucleus. - HIF induces VEGF and other angiogenic factors; oncogenes add more. - VEGF binds receptors on nearby endothelium, which sprouts and proliferates. - Proteases clear a path; new capillaries grow into the tumour. - The tumour now grows beyond its diffusion limit and gains access to the circulation. ## Clinical notes - Highly vascular tumours (renal cell carcinoma, hepatocellular carcinoma) often enhance in the arterial phase of imaging. - Anti-angiogenic therapies include antibodies against VEGF and small molecules against VEGF receptors. - Kaposi sarcoma, a vascular tumour linked to HHV-8, is a reminder that some tumours are made of vessels themselves. ## Memory aid No road, no city: a tumour stays a village until HIF and VEGF build the highway. ## Test yourself Think of the answer, then tap the question to see it. ## Which transcription factor links hypoxia to VEGF? HIF-1 alpha, which is stabilised in hypoxia and induces VEGF. ## Why is clear cell renal cell carcinoma so vascular? Loss of VHL prevents HIF degradation, so HIF continuously induces VEGF and other angiogenic genes. ## How does p53 loss favour angiogenesis? p53 normally induces anti-angiogenic factors such as thrombospondin-1; without p53 the balance tips toward angiogenesis. ## What are two adverse effects of anti-VEGF therapy? Hypertension and impaired wound healing (also bleeding, thrombosis and proteinuria). [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/general-pathology/tumour-angiogenesis/) ## Related - [The hallmarks of cancer](https://durgical.com/en/general-pathology/the-hallmarks-of-cancer/) - [Invasion and metastasis: the metastatic cascade, step by step](https://durgical.com/en/general-pathology/invasion-and-metastasis-the-metastatic-cascade-step-by-step/) - [Tumour suppressor genes: RB, TP53, APC, BRCA and the two-hit hypothesis](https://durgical.com/en/general-pathology/tumour-suppressor-genes-rb-tp53-apc-brca-and-the-two-hit-hypothesis/) - [Oncogenes: RAS, MYC, HER2, BCR-ABL and the table to know](https://durgical.com/en/general-pathology/oncogenes-ras-myc-her2-bcr-abl-and-the-table-to-know/) ## Related conditions - [Renal cell carcinoma](https://durgical.com/en/conditions/renal-cell-carcinoma/) - [Glioblastoma](https://durgical.com/en/conditions/glioblastoma/) - [Hepatocellular carcinoma](https://durgical.com/en/conditions/hepatocellular-carcinoma/) - [Colorectal cancer](https://durgical.com/en/conditions/colorectal-cancer/) - [Kaposi sarcoma](https://durgical.com/en/conditions/kaposi-sarcoma/) - [Lung cancer](https://durgical.com/en/conditions/lung-cancer/) - [Phaeochromocytoma](https://durgical.com/en/conditions/phaeochromocytoma/) - [Hereditary paraganglioma and pheochromocytoma (SDH)](https://durgical.com/en/conditions/hereditary-paraganglioma-and-pheochromocytoma/) ## Elsewhere in DurgiPedia - [Blood vessels: artery, vein and capillary layers](https://durgical.com/en/histology/blood-vessels-artery-vein-and-capillary-layers/) - [Receptor tyrosine kinases](https://durgical.com/en/biochemistry/topics/receptor-tyrosine-kinases/) - [Warburg effect (aerobic glycolysis in cancer)](https://durgical.com/en/biochemistry/topics/warburg-effect/) - [Local and humoral control of blood flow](https://durgical.com/en/physiology/local-and-humoral-control-of-blood-flow/) [← All of general pathology](https://durgical.com/en/general-pathology/) Educational content on the mechanisms of disease; not a diagnostic or treatment guide and no substitute for a health professional's advice. No doses are given. Sources: [Angiogenesis Inhibitors](https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/angiogenesis-inhibitors-fact-sheet) (National Cancer Institute (NCI), 2026); [VHL gene: MedlinePlus Genetics](https://medlineplus.gov/genetics/gene/vhl/) (MedlinePlus, US National Library of Medicine, 2026); [Metastatic Cancer: When Cancer Spreads](https://www.cancer.gov/types/metastatic-cancer) (National Cancer Institute (NCI), 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/general-pathology/tumour-angiogenesis/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/general-pathology/tumour-angiogenesis/