Metaplasia part 1

Question 1

What is transdifferentiation?

Answer 1

The conversion of one differentiated cell type to another (e.g. pancreatic cell to a liver cell)

Question 2

What is metaplasia?

Answer 2

The conversion of one cell type to another

Question 3

Diff between transdifferentiation and metaplasia?

Answer 3

Metaplasia can include conversion of one tissue stem cell to another

Question 4

Other name for Barretts Metaplasia?

Answer 4

Barrett’s Oesophagus

Question 5

What is Barrett’s Metaplasia?

Answer 5

The conversion of normal stratified squamous epithelium to columnar-line intestinal epithelium, in the oesophagus

Question 6

Where in the body does Barrett’s Metaplasia occur?

Answer 6

Oesophagus

Question 7

Which type of epithelium usually lines the oesphagus?

Answer 7

Stratified squamous epithelium

Question 8

What is the only known precursor to oesophageal adenocarcinoma?

Answer 8

Barrett’s Metaplasia

Question 9

What is Stratified Squamous Epithelium?

Answer 9

Flattened scale-like multi-layered epithelium

Question 10

Where in the oesophagus does Barrett’s occur?

Answer 10

Lower end

Question 11

What is an adenocarcinoma?

Answer 11

A malignant tumour of epithelial glandular origin

Question 12

What are some possible indicators of Barrett’s Metaplasia?

Answer 12

Difficulty swallowing combined w/ weight loss

Question 13

Where other than the oesophagus is SSQE found?

Answer 13

Skin and parts of the cervix

Question 14

Functions of SSQE in the oesophagus?

Answer 14

Protects against mechanical friction (food and liquid)
Protects against stomach acid which

Question 15

What happens in the oesophagus that allows stomach acid to enter?

Answer 15

The lower esophageal sphincter relaxes, allowing the acid to enter the oesophagus

Question 16

Which markers identify the basal layer of oesophageal SSQE

Answer 16

p63 TF, cytokeratins 5 and 14

Question 17

What is p63?

Answer 17

Master TF for SSQE

Question 18

What happens if p63 is knocked out in mice?

Answer 18

They don’t develop SSQE

Question 19

What kind of pairs are the cytokeratin pairs?

Answer 19

Acidic and basic pairs

Question 20

Which cytokeratin pairs are expressed higher up in the SSQE?

Answer 20

Cytokeratin 4/13, or 5/10

Question 21

What is expressed in the terminally differentiated SSQE cells?

Answer 21

Involucrin and loricrin

Question 22

Which cell types are present in the intestine?

Answer 22

Enterocyte, enteroendocrine, goblet cells, pitt cells, pallas cells

Question 23

Role of enterocyte in the intestine?

Answer 23

Absorption of nutrients into the blood

Question 24

Where are enterocytes found in the intestine?

Answer 24

Tips of the villus

Question 25

Which enzyme do enterocyte express?

Answer 25

Glucose-6-phosphatase

Question 26

Role of enteroendocrine cells?

Answer 26

Secretion of endocrine hormones--> e.g. glucagon-like peptide 1

Question 27

Which drug is a synthetic GLP1?

Answer 27

Ozempic

Question 28

Role of goblet cells?

Answer 28

Secretion of mucus

Question 29

Role of mucus in the intestine?

Answer 29

Lubrication of the contents of the intestine, protective layer over intestinal epithelium--> against stomach acid

Question 30

Role of pitt cells?

Answer 30

Unknown, believed to be involved in immune system

Question 31

Role of pallas cells?

Answer 31

Secrete lysosomes--> bactericidal agent

Question 32

What are pallas cells associated with?

Answer 32

Intestinal stem cell