Cancer Biology 1 - Types of Cancer, Mutations and Viral Oncogenesis

Question 1

What is Cancer

Answer 1

Abnormal growth of cells in an uncontrolled way that can spread of metastasise into other tissues

Question 2

What are the 2 types of tumours?

Answer 2

Benign and Malignant Tumours

Question 3

What are Benign Tumours?

Answer 3

Benign tumours are abnormal growths that are no longer under normal regulation

Question 4

What are Malignant Tumours?

Answer 4

Poorly differentiated cells, growing in a rapid, disorganised manner and can invade surrounding tissues and are become metastatic (initiating the growth of similar tumours in distant organs).

Question 5

What are the 4 types of cancers based on cell origin?

Answer 5

1. Carcinomas
2. Sarcomas
3. Lymphomas
4. Leukaemias

Question 6

Which is the most common type of cancer and what’s its percentage rate?

Answer 6

• Carcinomas (85%)
• Carcinomas cancer arises from the cells that cover external and internal body surfaces

Question 7

What are the 4 most frequent Carcinomas Cancers?

Answer 7

• Lung
• Breast
• Colon
• Adenocarcinoma (Glandular epithelial tissue)

Question 8

What percentage of Cancers are Sarcomas

Answer 8

12%

Question 9

From which cells does Sarcomas Cancer originate from?

Answer 9

From cells found in the supporting tissues of the body (mesenchymal layer-derived) such as bone, cartilage, fat, connective tissue, and muscle. It is highly malignant.

Question 10

What percentage of Cancers for Lymphomas and Leukaemia’s make up?

Answer 10

3%

Question 11

What is Lymphoma?

Answer 11

Lymphomas are cancers that arise in the lymph nodes and tissues of the body immune system (B, T and NK cells) that can spread to intestine, spinal cord, bone or brain.

Question 12

What is Leukaemia?

Answer 12

Leukaemia is cancer of immature white blood cells that proliferate in the bone marrow and accumulate in the bloodstream.

Question 13

What 5 factors is staging of cancer based on?

Answer 13

• Site of primary tumour
• Tumour size
• How far it has invaded into local tissues and structures
• Whether it has spread to regional lymph nodes
• Whether it has metastasised to other regions of the body

Question 14

What is Grading in Cancer

Answer 14

• Based on differences in microscopic cellular appearance, doctors assign a numerical “grade” to most cancers.
• A low number grade (Grade I or II) refers to cancers with fewer cell abnormalities that those with higher grades (Grade III or IV)

Question 15

Carcinogenesis is a multistep process resulting from the ______________ ____ ____________

Answer 15

Accumulation of mutations

Question 16

Normal cells evolve into cancer cells through what process?

Answer 16

Tumour Progression

Question 17

What is Tumour Progression driven by?

Answer 17

It is driven by a series of random mutations and epigenetic alteration (changes in DNA methylation) of DNA that affects the genes controlling proliferation and survival.

Question 18

Viruses can also cause cancer. True or False

Answer 18

True

Question 19

What are the 2 viral mechanisms of carcinogenesis?

Answer 19

Indirect and Direct

Question 20

All tumour viruses probably present direct and indirect mechanisms. True or False

Answer 20

True

Question 21

Which virus family does the virus EBV belong to?

Answer 21

Herpesviridae

Question 22

Which virus family does the virus HTLV-I belong to?

Answer 22

Retroviridae

Question 23

Which virus family does the virus HHV-8d belong to?

Answer 23

Herpesviridae

Question 24

Which virus family does the virus HBV belong to?

Answer 24

Hepadnaviridae

Question 25

Which virus family does the virus HCV belong to?

Answer 25

Flaviviridae

Question 26

Which virus family does the virus HPV belong to?

Answer 26

Papovaviridae

Question 27

Which virus family does the virus JCVe belong to?

Answer 27

Papovaviridae

Question 28

Which cells are infected by the EBV virus?

Answer 28

B cells, Oropharyngeal epithelial cells, lymphoid cells

Question 29

Which cells are infected by the HTLV-I virus?

Answer 29

T cells

Question 30

Which cells are infected by the HHV-8d virus?

Answer 30

Endothelial cells

Question 31

Which cells are infected by the HBV virus?

Answer 31

Hepatocytes

Question 32

Which cells are infected by the HCV virus?

Answer 32

Hepatocytes

Question 33

Which cells are infected by the HPV virus?

Answer 33

Cervical epithelial

Question 34

Which cells are infected by the JCVe virus?

Answer 34

Cells in the Central Nervous System

Question 35

What are 4 causes DNA mutations?

Answer 35

1. Mistakes in DNA replication 2. Nucleotides within DNA molecules undergo chemical changes spontaneously 3. Effect of mutagenic agents 4. Viruses

Question 36

What are the 2 types of mutagenic agents?

Answer 36

1. Physical agents (X-rays, UV rays etc) 2. Chemical agents (Vinyl chloride, nitrosamines etc)

Question 37

Name 3 DNA viruses

Answer 37

HBV, EBV, HPV

Question 38

Can one mutation cause cancer? yes or no

Answer 38

- No - Many mutations are required for cancer - Cancer is a multi-step process - 3-20 mutations are required to develop cancer

Question 39

What is Hyperplasia?

Answer 39

Increase in the number of cells but all cells exhibit normal regulatory control mechanisms.

Question 40

What is Neoplasia?

Answer 40

After dysplasia and metaplasia (cells become another less differentiated cell) ; neoplastic growth is rapid and results in a tumour, metastasis and acquisition of more mutations.