Molecular Pathology of Tumours

Question 1

What are the properties of malignant tumours?

Answer 1

Disordered proliferation
Disordered apoptosis
Disordered differentiation
Disordered relationship between proliferating cells and surrounding environment (invasion, metastasis, angiogenesis)

Question 2

Gene amplification

Answer 2

A normal protein is wildly overexpressed

Question 3

What is the effect of a mutation in the coding sequence on clonality?

Answer 3

A hyperactive protein is made in normal amounts = more cancer

Question 4

What is the effect of chromosome rearrangement on clonality?

Answer 4

normal protein overproduced or fusion to actively transcribed gene produces hyperactive fusion protein

Question 5

What are the general functions of caretaker proteins?

Answer 5

Maintains the integrity of the genome by promoting DNA repair

Question 6

What is the general function of gatekeeper proteins?

Answer 6

Inhibits unnecessary proliferation

Question 7

P53 Protein

Answer 7

DNA binding protein that is key in regulating when a cell proliferates and when it dies

Question 8

Stein Model of Tumour Evolution

Answer 8

Normal Epithelia > tumour suppressor gene lost > excessive epithelial proliferation > oncogene activated > small tumour > another suppressor gene lost > large tumour > p53 lost > invasive tumour > rapid accumulation of mutations > metastasis