Cancer

Question 1

Define benign

Answer 1

Non cancerous, remains encapsulated and the same cell type that it began as. Doesn’t invade surrounding tissues.

Question 2

Define adenocarcinoma

Answer 2

Cancer that starts in glandular tissues that make fluid or mucus eg breast

Question 3

Define proliferation

Answer 3

rapid reproduction of cells

Question 4

Define angiogenesis

Answer 4

new blood vessels form from pre existing ones

Question 5

Define oncogenes

Answer 5

Gene in certain circumstances can transform a cell into a tumour cell

Question 6

Define neoplasm

Answer 6

Abnormal cells (tumour). Excessive, uncoordinated and persistent.

Question 7

Define malignant

Answer 7

Cancerous. Neoplasm that is capable of invading surrounding tissues.

Question 8

Define replicative immortality

Answer 8

Normal human cells can only grow and divide a number of times and undergo apoptosis when they are no longer needed

Question 9

Define telomeres

Answer 9

compound structure at the end of chromosome

Question 10

Define metastasis

Answer 10

development of secondary malignant growths at a distance from primary cancer site

Question 11

Define proto oncogenes and oncogenes

Answer 11

Set of genes that normally code for proteins to start the cell cycle and cell proliferation. Oncogenes - activation on, in cancer cells oncogenes have been mutated to be constantly turned on to replicate cells, these are called oncogenes.

Question 12

Define sarcomas

Answer 12

rare form of cancer which grows in connective tissues like bones

Question 13

Define chemotherapy

Answer 13

cancer treatment used to kill cancerous cells

Question 14

Define leukaemia

Answer 14

blood cancer

Question 15

Define lymphoma

Answer 15

Group of blood and lymph tumours that develop from lymphocytes

Question 16

What are the 6 stages of the pathophysiology of cancer

Answer 16

Unlimited proliferation, evading growth suppressors, resistance to cell death, replicative immortality, angiogenesis, invasion and metastasis

Question 17

Explain unlimited proliferation

Answer 17

Cell division without growth stimulatory factors (proto oncogenes), so continuous growth.

Question 18

Explain evading growth suppressors

Answer 18

Cancer cells do not respond to growth inhibitory signals, tumour suppressor gene is off

Question 19

Explain resistance to cell death

Answer 19

Evading cell death - evade apoptosis signals

Question 20

Explain replicative immortality

Answer 20

replicative potential of cancer cells, telomeres maintained

Question 21

Explain angiogenesis

Answer 21

Cancerous cells have alot of new mutations making the cell increase in size, so it will quickly run out of nutrients, oxygen and glucose and will have alot of waste to get rid of. The cells need new method of obtaining nutrients so cells encourage new blood vessel formation and triggers vascular growth.

Question 22

Explain invasion and metastasis

Answer 22

Cancer cells can move to other parts of the body

Question 23

Explain why benign tumours can cause problems

Answer 23

By compression of structures, blood vessels and nerves. Affects organs that secrete hormones that disrupt normal homeostasis.

Question 24

Where do haematological malignancies arise from ?

Answer 24

Blood and bone marrow cells

Question 25

Why are cancerous cells resistant to apoptosis ?

Answer 25

Mutational change in the genes that prevents apoptosis from naturally occurring.

Question 26

Explain replicative immortality

Answer 26

Normally when cell copies DNA you have protective ends on the DNA (telomeres) every time a cell copy is made, telomeres are shortened. Cells usually only have a certain amount of time they can be copied. In cancer mutations telomeres do not shorten or they are constantly getting longer which results in immortality of these cells.

Question 27

What is a risk of angiogenesis ?

Answer 27

Cancerous cells have a rich blood supply so there is a high risk of bleeding.

Question 28

Explain invasion and metastasis

Answer 28

Cancer cells can break away from primary tumour and be carried on the blood and lymphatic system. Cells must pass through the basement membrane. Move through the extracellular space and penetrate the basement membrane of blood or lymphatic vessel. Involves loss of adhesion between cells and release of enzymes that digest the basement membrane. Reaches new tissue and moves through basement membrane. In new tissues cancer cells go through angiogenesis.

Question 29

What are the risk factors for gene damage ?

Answer 29

Mutations occur in the normal process of cell division. The older we are the more cell division we made. Some tissues have more frequent cell division or constant replacement for eg GI tract. Therefore age and certain tissue types put us naturally at a higher risk

Question 30

What are some evidence based risk factors for cancer ?

Answer 30

Over 65, smoker, alcohol, UV, asbestos, radon, diet, physical activity

Question 31

What is the involvement in viruses and bacteria in cancer ?

Answer 31

Thought to influence development of cancer, causing genetic changes.

Question 32

Explain hereditary cancer, giving examples from TP53, BRCA1, BRCA2 and APC genes

Answer 32

Researchers have associated mutations in specific genes with more than 50 hereditary cancers which are disorders that may predispose individuals to developing certain cancers. Most commonly mutated gene in all cancers is TP53 which produces a protein that suppresses the growth of tumours. Inherited mutations in BRCA1 and BRCA2 genes are associated with hereditary breast and ovarian cancer syndrome, these genes are tumour suppressor genes when either of these genes acquire mutations cells are more likely to develop cancer * BRCA1 and BRAC2 are inherited from either a mother or a father * APC gene produces a protein that helps control how often a cell divides APC gene mutation can occur in colorectal cancer

Question 33

Explain Gleason's pattern scale

Answer 33

Describe neoplasm in terms of cell abnormality, cancer cells exhibit degrees of differentiation, how well developed cancer cells are and how they are organised in the tissue

Question 34

Explain the difference between well and poor differentiated

Answer 34

Well - if cells and tissue structures are similar to normal Poor - cells look abnormal and are more likely to invade surrounding tissue

Question 35

What are the 4 differentiating characteristics of cancerous cells ?

Answer 35

Staging - location and pattern of spread Tumour - size and how far it has spread Lymph nodes - whether it has spread to lymph nodes Metastasised - spread to other parts of the body

Question 36

Explain chemotherapy process

Answer 36

* Drugs act on different phases of the cell cycle * Directly interfere with DNA * Inhibit enzymes related to DNA synthesis * Destroy cell proteins * Cell cycle-specific – acting on cells undergoing division within the cell cycle * Mitotic poisons prevent spindle formation * Cell cycle non specific – cells in either dividing or resting phases * Alkylating agents that bind to DNA molecule disabling cell division

Question 37

What are the hallmarks of cancer ?

Answer 37

Acquired capabilities that allow cancer cells to survive, proliferate and spread.

Question 38

Explain cancer as a disease of dividing cells

Answer 38

All of our cells divide at different rates. In order for a cell to divide, cell needs signals to tell the other cell when to divide and when to stop. Every cell has DNA, parts of this DNA are called genes and these code for proteins. For a cell to become abnormal then something has to have grown wrong in the DNA. In cancer cells they have to have multiple genetic mutations