metastasis 1

Question 1

what is metastasis

Answer 1

the process where cancer cells that originate in one part of the body end up in other places and form secondary tumours

Question 2

where do prostate cancer cells normally metastasise to

Answer 2

bone marrow

Question 3

where do colon cancer cells normally metastasise to

Answer 3

liver

Question 4

where do breast cancer cells normally metastasise to

Answer 4

lungs and bone marrow

Question 5

where do pancreatic cancer cells normally metastasise to

Answer 5

liver

Question 6

overview of metastasis - 6 steps

Answer 6

primary tumour forms, the tumour cells invade into surrounding tissue, they meet barriers e.g. blood vessel walls and so they start to break through (intravasation), they interact with blood platelets and immune cells when in blood, they attach to the blood vessel wall and do extravasation. they then multiply and form a micrometastasis from there colonization occurs where a 2º tumour forms

Question 7

why do cancer cells have to invade surrounding tissues

Answer 7

they divide more than they need to and they arent dying so there is a big mass of cells

Question 8

what is intravasation

Answer 8

to invade across a blood vessel barrier and get into the blood supply

Question 9

what is extravasation

Answer 9

moving out the blood vessel

Question 10

what is a micrometastasis

Answer 10

a very small collection of tumour cells that are in a different location

Question 11

what happens to most micrometastasis’

Answer 11

they invade new tissue and form and don’t grow

Question 12

what is another name for 2º tumours

Answer 12

macrometastasis

Question 13

define epithelial cell

Answer 13

cells that line tube structures

Question 14

properties of epithelial cells (4)

Answer 14

polygonal/columnar shape, apico-basolateral polarisation, strong cell-cell adhesion, limited migratory potential

Question 15

what is apico-basolateral polarisation

Answer 15

a type of cell polarity specific to epithelial cells, they have different faces

Question 16

what cell is an example of a mesenchymal cell

Answer 16

white blood cell

Question 17

difference between epithelial and mesenchymal cells in relation to movement

Answer 17

mesenchymal cells move around whereas epithelial cells stay in the same place

Question 18

what are the markers for epithelial cells (4)

Answer 18

E-cadherin, certain cytokertins, occludin, claudin

Question 19

what is e-cadherin

Answer 19

cell surface protein that acts as a molecular ‘velcro’ that sticks cells together

Question 20

properties of mesenchymal cells (4)

Answer 20

spindle shape, anterior-posterior polarization, focal cell-cell contacts, strong migratory potential

Question 21

markers for mesenchymal cells (3)

Answer 21

vimentin, N-Cadherin, fibronectin

Question 22

what does apical mean

Answer 22

top surface

Question 23

what does basolateral mean

Answer 23

side surfaces

Question 24

what does “spindle-shaped” mean

Answer 24

pointy

Question 25

what does anterior-posterior polarisation

Answer 25

they have a head and a tail, they have a directionality

Question 26

what are focal cell-cell contacts

Answer 26

grabbing onto something and pulling themselves along, make and break contact

Question 27

epithelial gene expression programme

Answer 27

epithelial cells have the ability to make all the proteins they need to be epithelial cells

Question 28

what type of protein is E-cadherin

Answer 28

transmembrane protein

Question 29

what does it mean when you say E-cadherin can dimerise

Answer 29

a molecule of E-cadherin can interact with a molecule of E-cadherin from another epithelial cell

Question 30

what happens to epithelial cells in cancer

Answer 30

they can change into mesenchymal cells and start interacting with the extra cellular matrix

Question 31

what do epithelial cells lose when they become cancerous (4)

Answer 31

cytokeratin expression, tight junctions and junctions involving e-cadherin, epithelial cell polarity, epithelial gene expression program

Question 32

what do epithelial cells acquire when they become cancerous (6)

Answer 32

fibroblast-like shape, motility, invasiveness, increased resistance to apoptosis, mesenchymal gene expression program, mesenchymal adherens junction protein (N-cadherin)

Question 33

what makes a cell be able to change its gene expression program

Answer 33

transcription factors

Question 34

what do most EMT (epithelial-mesenchymal transition) transcription factors do

Answer 34

repress E-cadherin expression

Question 35

what does TWIST transcription factor do

Answer 35

binds to DNA and represses the promotor of the CDH1 gene which produces e-cadherin. Cell becomes mesenchymal

Question 36

TWIST cancer association

Answer 36

lots of cancer cells have high levels of TWIST, it induces cells to migrate to different places and its meant to be just in the embryo but cancer cells produce it anywau

Question 37

3 other examples of genes/proteins that repress E-cadherin

Answer 37

Goosecoid, Slug (SNAI2), Snail (SNAI1)

Question 38

what is the basement membrane made of

Answer 38

proteins - collagen fibre network

Question 39

how do cancer cells get through the basement membrane

Answer 39

they produce matrix metalloproteinases (MMP-1)

Question 40

what is MMP-1

Answer 40

a gene that encodes collagenase-1

Question 41

what does collagenase do

Answer 41

breaks down collagen, can break up collagen fibres in basement membrane

Question 42

what does the degradation of the extra cellular matrix produce

Answer 42

growth factors, which can then help cells to grow