Breast remodelling

Question 1

Mammary gland

Answer 1

Laminin rich BM
Stromal collagen matrix
Mammary ducts and lobular alveoli that produce milk

Question 2

What cells produce milk?

Answer 2

Luminal epithelial cells

Question 3

What surrounds mammary glands?

Answer 3

Adipose fat pad

Question 4

BM composition

Answer 4

Laminins
Collagen
Nidogen/Entactin
Proteoglycans

Question 5

Integrin

Answer 5

TMR linking ECM to focal adhesion complex

Question 6

Deletion of B1 integrin`

Answer 6

Decreased alveoli proliferation

Question 7

Milk production

Answer 7

Prolactin stim Jak/STAT pathway and milk is produced (measure B-casein levels)

Question 8

ECM in milk production - experiment

Answer 8

No milk on unpermissive substrate

Laminin - milk production

Question 9

B1 KO

Answer 9

Smaller pups - decreased milk fat and milk pt

Question 10

KO FAK

Answer 10

no effect - not req for lactational differentiation

Question 11

KO ILK

Answer 11

Decreased pup weight and milk fat

Down-stream of B1

Question 12

Rac1 experiments

Answer 12

ILK and B1 KO - decreased Rac1
CA Rac1 rescues milk expression in ILK defective MEC organoids
CA Rac1 stim B-casein exp on non-permissive substrate
KO Rac1 = decreased diff of alv

Question 13

B1 integrin KO and lumen

Answer 13

Abnormal lumen formation

Question 14

What happens to apical-basal polarity in B1 KO

Answer 14

Reversed - cells don’t remodel their membranes
B1 needed for
- reorientation of apical polarity
- maintaining this polarity