22 Tumour behaviour Flashcards
What are the mechanisms of tumour invasion?
Increased motility.
Decreased adhesion.
Proteolytic enzyme secretion.
Mechanical pressure.
Which molecule controls cell to cell adhesion?
E-cadherin.
Which molecule controls cell to matrix adhesion?
Integrins.
Differentiate between epithelial and mesenchymal cells.
Epithelial: tightly connected, polarised and tethered.
Mesenchymal: loosely connected and able to migrate.
Which proteolytic enzymes do invasive neoplasms produce?
Matrix metalloproteinases.
What do interstitial collagenases break down?
Collagen type I, II, III.
What do gelatinases break down? (2).
Collagen type IV.
Gelatin.
What do stomolysins break down? (2).
Collagen type IV.
Proteoglycans.
How does mechanical pressure aid tumour invasion?
Tumour forms mass, occludes vessel, atrophies surrounding tissue and invades along lines of least resistance.
What are the eight stages of metastasis?
Detachment. Invasion. Intravasation (gets into blood vessels) Survival against host defences. Adherence. Extravasation (gets out of blood vessels). Growth. Angiogenesis.
What are the two theories surrounding tumour metastasis?
Mechanical: anatomy driven.
Seed and soil hypothesis.
What are the two types of bone mets?
Where does each come from?
Lytic: lung.
Sclerotic: prostate.
Which proteins inhibit angiogenesis? (4).
ECM proteins.
Thrombospondin.
Canstatin.
Endostatin.
What is the stage of a cancer?
How advanced is the tumour?
Where has it spread to?
What is the grade of a cancer?
How aggressive is it?
How different does it look from the tissue of origin?
