Neoplasia 3

Question 1

What binds cells to each other?

Answer 1

• cadherins

Question 2

How do cells degrade the basement membrane?

Answer 2

• release proteases, that cleave the basement membrane

Question 3

How does the cell migrate through the basement membrane?

Answer 3

• autocrine signalling (effect yourself)
  
  • this moves the cell forward through the membrane
  • the cell starts to express different binding proteins, so can bind different substances

Question 4

Describe the mechanism(s) of invasion and metastasis (use example of how tumour spreads into bloodstream)

Answer 4

• cell breaks through basement membrane
• subclone of tumour formed- now wants to migrate
• now in ECM
• invades through ECM - and it hopes it reaches a blood vessel
• invades through basement membrane etc. to get into bloodstream
• tumour cells interact with wbcs, and can trigger platelets to stick to them = form an embolus to move through blood
• adheres to endothelium
• may hijack wbcs to get out of blood vessel
• recruit more blood vessels
• now have metastatic tumour

Question 5

What are the metastatic pathways?

Answer 5

• lymphatic spread
• haematogenous spread
• transcoelomic spread
• and direct invasion

Question 6

• What are the white spaces around blue circles
• and what is this slide showing?
• What is the type of all the cells shown?
• What type of tumour is shown?

Answer 6

• white spaces = sinus (where lymph comes in to be filtered)
• slide = lymphatics (drain tissue)/ top is the capsule)
• all cells are epithelial = so it is a carcinoma in a lymph node

Question 7

How are most carcinomas spread?

Answer 7

• through lymphatics

Question 8

How are most sarcomas spread?

Answer 8

• through bloodstream (haematogenous)

Question 9

What is this showing?

Answer 9

• metastatic haemangiosarcoma

Question 10

What is transcoelomic spread?

Answer 10

• direct spread across cavities or surfaces

Question 11

What is Carcinomatosis?

Answer 11

• spread of epithelial tumours (ovarian/pancreatic) across body cavities

Question 12

What is this showing?

Answer 12

• ovarian tumour in chicken
• all of white - tumour

Question 13

What does paraneoplastic effect mean?

Answer 13

• clinical sign that occurs because of the tumour (may not be direct)