2. Mechanisms Of Angiogensis I

Question 1

What does H&E stain and what does it stand for

Answer 1

• hematoxylin and eosin
• stains cytoplasm/membranes

Question 2

List some types of cells that make up the tumour stroma

Answer 2

• cancer-associated fibroblasts
• endothelial cells
• neo-angiogenic endothelial cells
• macrophages
• lymphocytes

Question 3

Which cell type forms the blood vessel lining?

Answer 3

Endothelial

Question 4

Explain the angiogenic switch concept

Answer 4

When dormant, anti-/pro- apoptotic factors remain balance, with an abundance of anti angiogenic factors
In a tumour, the balance is shifted; the switch.

Question 5

What are some aniogenic activators and inhibitors

Answer 5

Activators: VEGFs, FGFs, PDGFB, EGF, LPA
Inhibitors: Thrombospodin1, angiostatin, endostatin, canstatin, tumstatin

Question 6

What stage does embryonic vasculogenesis occur?

Answer 6

E8.5

Question 7

What is vasculogenesis

Answer 7

Growth of primitive vessels from original angioplast source

Question 8

What is vessel-caption an when is it seen

Answer 8

Tumours growing along existing blood vessels
Seen frequently in gliomas and following anti-angiogenic therapy

Question 9

What are mouse retinas studied at 5 days old?

Answer 9

The eyes have fully formed but have not opened yet, so angiogenesis is pronounced, but oxygen must be from he mouse’s own vasculature

Question 10

In what ways may growing ECs behave differently to non-growing ECs?

Answer 10

• proliferation
• migration
• change in mural support
• change in lumenisation
• change in metabolism
• different interactions with surrounding cells and ECM

Question 11

What are some features of tip cells?

Answer 11

• at the end of growing spout
• filopedia rich
• covered in growth factor receptors
• highly motile
• not perfused
• ‘pathfinding’

Question 12

What techniques can be used to study endothelial cells

Answer 12

• immunohistochemistry: fluorescent antibodies
• single cell RNAseq: analyse transcriptome of endothelial cells

Question 13

How can you isolate endothelial cells to perform RNAseq?

Answer 13

Using a panEC marker and immunopurification

Question 14

What % of endothelial cells do tip cells make up?

Answer 14

5%

Question 15

Why is the fact that angiogenic ECs are highly immunospenic important?

Answer 15

They may be able to modulate immune response by delivering immune cells to the tumour