Neoplasia 2

Question 1

what are the two main factors of carcinogenesis?

Answer 1

genetic and environmental

Question 2

what are the important genes in carcinogenesis?

Answer 2

oncogenes, tumour suppressory genes, DNA repair genes, miRNAs

Question 3

what does DNA damage lead to?

Answer 3

altered gene expression and then altered cell function

Question 4

what are proto-oncogenes?

Answer 4

normal genes which regulate cell division

Question 5

what are the roles of proto-oncogenes?

Answer 5

growth factors, growth factor receptors, signal transducers, control of gene expression

Question 6

what do oncogenes produce?

Answer 6

oncoproteins

Question 7

what are abnormal variants of proto-oncogenes called?

Answer 7

oncogenes

Question 8

if tight regulation is lost, what can oncogenes do

Answer 8

mutations, excess activity of product, enhanced transcription

Question 9

what do the mutations in the oncogenes cause?

Answer 9

increased activity of the product

Question 10

what is the cause of excess amounts of the normal product?

Answer 10

duplication of the gene, viral product

Question 11

what occurs in enhanced transcription?

Answer 11

translocation or chromosome rearrangement

Question 12

what do tumour suppressor genes do?

Answer 12

act to inhibit cell division and suppress growth

Question 13

what do tumour suppressor genes require?

Answer 13

loss of both alleles

Question 14

give an example of a tumour suppressor gene

Answer 14

retinoblastoma gene

Question 15

what are the inherited factors of cancer?

Answer 15

inherited cancer syndromes, familial cancer, defective DNA repair

Question 16

what are the inherited cancer syndromes?

Answer 16

single mutant genes, often tumour suppressor genes, retinoblastoma, some colon cancers

Question 17

what are the familial cancers?

Answer 17

family clusters, genes and pattern of inheritance, breast, ovary and colon

Question 18

what results due to defective DNA repair

Answer 18

increased sensitivity to carcinogens and general increased cancer risk

Question 19

give an example of a defective DNA repair cancer

Answer 19

xeroderma pigmentosum

Question 20

what is P53?

Answer 20

the guardian of the genome

Question 21

when does P53 act?

Answer 21

just before the restriction point in the cell cycle

Question 22

what are the 2 main functions of P53 in response to damaged DNA

Answer 22

stops the cell cycle to allow DNA repair or apoptosis (if repair is not possible)

Question 23

what happens to P53 during cancer?

Answer 23

it is often inactivated by mutation or deletion or viral proteins (HPV)

Question 24

what is affected if P53 is mutated/deleted?

Answer 24

other cell division controls, DNA repair mechanisms, apoptosis inhibited, stimulation of blood vessel formation, destructive enzymes activated, cell motility increased

Question 25

what are the hallmarks of cancer?

Answer 25

insensitivity to anti-growth signals, tissue invasion and metastasis, limitless replicative potential, sustained angiogenesis, evading apoptosis, self-sufficiency in growth signals

Question 26

what is the process of carcinogenesis?

Answer 26

multistep - initiation, promotion, progression

Question 27

what are the modes of spread of malignant tumours?

Answer 27

local spread, lymphatic spread, blood spread (haematogenous), transcoelomic spread, intraepithelial spread

Question 28

what is metastasis?

Answer 28

the spread of malignant cells to distant organ forming secondary tumours

Question 29

how do carcinomas spread?

Answer 29

lymphatic and later blood

Question 30

how do sarcomas spread

Answer 30

blood (lymphatic spread is rare)

Question 31

where do cancers of the lung spread to?

Answer 31

local nodes, liver, bone and brain

Question 32

where do cancers of the tongue spread to?

Answer 32

neck nodes, later lung and spine

Question 33

what are the steps of metastasis?

Answer 33

intravasation, survival in the circulation, arrest in organ, extravasation, survival of cells after extravasation, initial growth of cells after extravasation, persistence of growth

Question 34

what can tumour cells do?

Answer 34

alter adhesion molecules, make poor basement membrane, increase protease production or reduce inhibitors, alter extracellular matrix

Question 35

when talking about grading and staging, what does grade mean?

Answer 35

biological nature of the tumour (histopathology)

Question 36

when talking about grading and staging, what does stage mean?

Answer 36

extent of spread (clinical)

Question 37

what is grading?

Answer 37

a histological assessment of invasion into underlying tissue and cellular atypia

Question 38

what does cellular atypia include?

Answer 38

mitotic activity, nuclear pleomorphism, differentiation, necrosis

Question 39

what are the methods of grading?

Answer 39

numerical, low/intermediate/high, degree of differentiation (SCC)

Question 40

what type of grading is used for squamous cell carcinomas?

Answer 40

degree of differentiation

Question 41

what does pleomorphism cover?

Answer 41

variation in cell shape and size, variation in nuclear shape and size

Question 42

what can be seen in cells of a malignant tumour?

Answer 42

numerous mitoses, abnormal mitoses, variable differentiation

Question 43

what does staging mean?

Answer 43

the extent or severity of a persons cancer

Question 44

what does knowing the staging of the cancer help?

Answer 44

planning treatment and estimating the persons prognosis

Question 45

what is used to determine staging?

Answer 45

physical exams, imaging procedures, laboratory tests, pathology and surgical reports

Question 46

what system is used for staging of oral cancer?

Answer 46

TNM

Question 47

what does T stand for in TNM?

Answer 47

tumour size

Question 48

what does N stand for in TNM?

Answer 48

lymph node involvement

Question 49

what does M stand for in TNM?

Answer 49

presence of metastases

Question 50

what are the clinical effects of lung cancer?

Answer 50

cough, haemoptysis, chest pain, pneumonia

Question 51

what are the systemic effects of cancer often caused by?

Answer 51

cytokines or hormones released by tumour cells or dysfunction of the organ

Question 52

what are the systemic effects of cancer?

Answer 52

fever, anorexia, weight loss/cachexia, neurological problems e.g. neuropathy, endocrine sydromes e.g. Cushings syndrome, metabolic effects e.g. hypercalcaemia

Question 53

how do you treat malignant tumours?

Answer 53

surgery, chemotherapy and radiotherapy

Question 54

what is tumour immunology?

Answer 54

immune surveillance

Question 55

what can tumour immunology do?

Answer 55

suppress or enhance carcinogenesis

Question 56

what is elimination-equilibrium-escape

Answer 56

how does the immune system recognise tumour cells

Question 57

what are the tumour associated antigens?

Answer 57

products of mutated genes, overexpressed proteins, viral proteins, oncofetal antigens

Question 58

what is elimination?

Answer 58

cell mediated immune response

Question 59

what immune cells contribute to elimination?

Answer 59

CD8+, NKC (first line of defence against tumour cells), macrophages

Question 60

what can immunodeficiency lead to?

Answer 60

an increased incidence of malignant tumours

Question 61

what does elimination lead to?

Answer 61

escape

Question 62

what is escape

Answer 62

how do tumour cells evade the immune response

Question 63

how do tumour cells escape?

Answer 63

acquire molecular changes such as alter tumour antigen expression (lack of T cell recognition), activation of immunoregulatory pathways leading to T cell unresponsiveness and apoptosis, immunosuppressive factors e.g. cytokines (inhibit T cell response)

Question 64

what is immunotherapy?

Answer 64

using the patients own immune response to control and destroy malignant cells

Question 65

what are the methods of immunotherapy?

Answer 65

active immunisation, reversal of immunosuppression, adopted cell transfer, strengthening natural immune responses

Question 66

when is immunotherapy used?

Answer 66

in advanced stage of disease

Question 67

when is immunotherapy most successful?

Answer 67

in haematological malignancies