L01 What is cancer?

Question 1

What is cancer

Definition of cancer? L01

Answer 1

Uncontrolled growth of abnormal cells in a tissue, invasive and metastasising

Question 2

What is cancer

What is a carcinoma? L01

Answer 2

Cancer of epithelial cells

Question 3

What is cancer

What is an adenocarcinoma? L01

Answer 3

A carcinoma featuring microscopic glandular-related tissue cytology, tissue architecture, and/or gland-related molecular products

Question 4

What is cancer

What is a squamous cell carcinoma? L01

Answer 4

Refers to a carcinoma with observable features and characteristics indicative of squamous differentiation (intercellular bridges, keratinisation, squamous pearls)

Question 5

What is cancer

List the three most common sites of adenocarcinoma? L01

Answer 5

Lung
Colon
Breast

Question 6

What is cancer

List the three most common sites of squamous cell carcinoma? L01

Answer 6

Skin
Nasal cavity
Oropharynx

Question 7

What is cancer

What is a sarcoma? L01

Answer 7

Cancer of cells of mesenchymal origin e.g. osteosarcoma (osteoblasts), fibrosarcoma (fibroblasts), chondrosarcoma (chondroblasts)

Question 8

What is cancer

What is a leukaemia? L01

Answer 8

Cancer of leukocytes that usually begins in bone marrow

Question 9

What is cancer

What is a lymphoma? L01

Answer 9

Cancer of lymphocytes

Question 10

What is cancer

What is a cancer of the plasma cells called? L01

Answer 10

Myeloma

Question 11

What is cancer

What are four types of leukaemia? L01

Answer 11

Acute lymphocytic
Acute myelogenous
Chronic lymphocytic
Chronic myelogenous

Question 12

What is cancer

What is a cancer of the central and peripheral nervous system called? L01

Answer 12

Neuroectodermal tumours

Question 13

What is cancer

What is a glioblastoma multiforme? L01

Answer 13

A highly progressed cancer of the astrocytes

Question 14

What is cancer

What is an ependymoma? L01

Answer 14

Cancer of cells lining the ventricles of the brain

Question 15

What is cancer

What are the types of gene that normally initiate cancer? L01

Answer 15

Genes that control:

• growth
• the cell cycle
• stem cells
• integrity of genome + repair

Question 16

What is cancer

How do mutations arise? L01

Answer 16

Copying errors during DNA replication
Spontaneous depurination
Exposure to different agents e.g. UV light, tobacco, background ionising radiation

Question 17

What is cancer

Of what clonal growth is cancer? L01

Answer 17

Monoclonal

Question 18

What is cancer

What is a tumour suppressor gene’s function? L01

Answer 18

Negative regulator of cell growth (prevents growth), even when one allele is mutated. Need to lose both alleles to lose suppressor effect

Question 19

What is cancer

What is the function of an oncogene? L01

Answer 19

Positive regulator of cell growth, makes cells grow, even when one allele is mutated

Question 20

What is cancer

What are the six hallmarks of cancer? L01

Answer 20

Resisting cell death
Sustaining proliferative signalling
Evading growth suppressors
Activating invasion and metastasis
Inducing angiogenesis
Enabling replicative immortality

Question 21

What is cancer

Explain how cancer cells are self-sufficient in growth signals. L01

Answer 21

Ligand independent firing; they can signal without extracellular factors
Autocrine signalling; they secrete their own GFs

Question 22

What is cancer

What is the function of Ras protein? L01

Answer 22

It controls intracellular signalling pathways including proliferation, differentiation, cell adhesion, apoptosis and cell migration

Question 23

What is cancer

What is the significance of Ras protein in cancers? L01

Answer 23

Ras and Ras-related proteins are often deregulated in cancers, leading to invasion and metastasis, and decreased apoptosis

Question 24

What is cancer

How are cancer cells insensitive to anti-growth signals? L01

Answer 24

Disruption of pRB pathway. pRB controls the restriction point in the cell cycle from G0 to S stages. It is normally determined by tumour suppressor genes but cancer cells evade this mechanism.

Question 25

# What is cancer How do cancer cells evade apoptosis? L01

Answer 25

They increase anti-apoptotic regulators e.g. P13K | They decrease pro-apoptotic regulators e.g. cytochrome C, p53, through loss or mutations

Question 26

# What is cancer What is the function of p53? L01

Answer 26

p53 causes cell cycle arrest, DNA repair, angiogenesis block, and apoptosis. It is a pro-apoptotic regulator

Question 27

# What is cancer How do cancer cells create a limitless replicative potential? L01

Answer 27

They escape crisis by adding telomeres to the ends of DNA. They bypass senescence.

Question 28

# What is cancer How do cancer cells sustain angiogenesis? L01

Answer 28

Control the transcription of angiogenic activators and down-regulate angiogenic inhibitors

Question 29

# What is cancer Example of angiogenic activators? L01

Answer 29

VEGF-A, -B, -C | FGF1, FGF2

Question 30

# What is cancer Example of angiogenic inhibitors? L01

Answer 30

``` Thrombospondin-1, -2 INFalpha and beta Angiostatin Endostatin Collagen IV fragments ```

Question 31

# What is cancer Define metastasis. L01

Answer 31

Multistep process leading to the spread of cancer to distant organs

Question 32

# What is cancer What are the two emerging hallmarks of cancer? L01

Answer 32

Deregulating cellular energetics (glycolytic switch) | Avoiding immune destruction (secrete immunosuppressive factor)

Question 33

# What is cancer What are the two enabling characteristics of cancer? L01

Answer 33

Genome instability and mutation | Tumour-promoting inflammation

Question 34

# What is cancer How does growth occur in cancerous cells? L01

Answer 34

Selective clonal selection