13. Tumour Markers, Cell Cycle, Carcinogenesis

Question 1

Why is carcinogenesis associated with old age?

Answer 1

Enough time to be exposed to many carcinogens

The elderly are also mildly immunosuppressed

Question 2

Why do some cancers occur in childhood?

Answer 2

Due to inherited mutations

Question 3

What are tumour markers?

Answer 3

Antigens made by or on the surface of the tumour

Question 4

Why are tumour markers clinically useful?

Answer 4

Diagnosis
Follow up
Screening

Question 5

What tumours produce CEA?

Answer 5

Colon
Stomach
Pancreas

Question 6

What tumour marker is made by a choriocarcinoma?

Answer 6

hCG

Question 7

What tumour marker is produced by a hepatocellular carcinoma or yolk sac tumour?

Answer 7

AFP

Question 8

What tumour marker is produced in a prostatic carcinoma?

Answer 8

PSA

Question 9

What samples can tumour markers be found in?

Answer 9

Blood
Urine
Tissue section

Question 10

What immunohistochemical stain is used to show a carcinoma?

Answer 10

Cytokeratin

Question 11

What immunohistochemical stain is used to show a sarcoma?

Answer 11

Vimentin

Question 12

What immunohistochemical stain is used to show a lymphoma?

Answer 12

CD45

Question 13

What immunohistochemical stains are used to show a melanoma?

Answer 13

S100P

Melan A

Question 14

What immunohistochemical stain is used to show a thyroid tumour?

Answer 14

Thyroglobulin

Question 15

What proteins control the cell cycle?

Answer 15

Oncoproteins

Tumour suppressor proteins

Question 16

What is hyperplasia?

Answer 16

Increased cell proliferation due to a controlled response to a stimulus
Stops when the stimulus is withdrawn

Question 17

Give the stages of the cell cycle

Answer 17

G0
G1
S
G2
M

Question 18

What is metaplasia?

Answer 18

1 adult epithelium changes to another type

Normally protective but can have malignant potential

Question 19

Give an example of metaplasia

Answer 19

Barrett’s oesophagus

Question 20

Which gene is altered in familial breast cancer?

Answer 20

BRAC 1 or 2

Question 21

What is the normal role of proto-oncogenes?

Answer 21

Regulate normal cell proliferation

Question 22

What is another name for an active proto-oncogene?

Answer 22

Cellular proto-oncogene

Question 23

What processes can cause proto-oncogenes to be upregulated?

Answer 23

Point mutation
Amplification
Translocation
Insertion of viral DNA
Methylation (environmental)

Question 24

How does the Epstein-Barr virus cause Burkitt’s lymphoma?

Answer 24

Causes a translocation which activates c-myc proto-oncogene

Question 25

What is the normal role of tumour suppressor gene?

Answer 25

Suppress cell proliferation

Question 26

How can tumour suppressor genes be inactivated?

Answer 26

Deletion
Mutation
Translocation

Question 27

Name 2 tumour suppressor genes

Answer 27

APC (lost in familial colon cancer)

P53

Question 28

What is the function of repair genes?

Answer 28

Repair DNA defects

Question 29

What is the role of anti-apoptotic genes in carcinogenesis?

Answer 29

Give a survival advantage to tumour cells

Question 30

Name an anti-apoptotic gene

Answer 30

BCL2

Question 31

How do tumour cells evade immune detection?

Answer 31

Tolerance
Local suppression of immune cells
Dysfunction in T cell signalling

Question 32

What receptor on lymphocytes allows tumour cells to suppress them?

Answer 32

PD1

Question 33

What are the classes of carcinogens?

Answer 33

Chemicals
Radiation
Hormones
Viruses
Chronic inflammation
Parasites