Cancer

Question 1

What is cancer defined as

Answer 1

A collection of diseases caused when cells divide uncontrollably and spread into surrounding tissues

Question 2

What is a carcinoma

Answer 2

a type of cancer that affects epithelial tissue often seen in breasts lungs and livers. It is the most common form of cancer.

Question 3

What is Sarcoma

Answer 3

A cancer that affects the connective tissue often seen in bones and muscle

Question 4

what is a hematological malignancy

Answer 4

a type of tumor caused by the disruption of normal hematopoeitic function e.g. myeloma, lymphoma and leukemia

Question 5

what is myeloma

Answer 5

a type of hematological malignancy that can be seen in plasma cells in the bone marrow tissue

Question 6

what is leukaemia

Answer 6

a type of hematological malignancy that affects the white blood cells and red blood cells in the bone marrow

Question 7

If a condition ends in the term oma what does this indicate

Answer 7

lipoma and adenoma are examples of this convention and highlights a benign tumour

Question 8

what is a benign tumour

Answer 8

stay in their primary location without invading other tissues

Question 9

what is a malignant tumur

Answer 9

tumors that spread beyond their initial site and are considered more dangerous

Question 10

define the term neoplasm

Answer 10

a new disorganized growth often related to cancer where there is a net increase in cells.

Question 11

what is carcinogenesis

Answer 11

the prcess of forming a cancer

Question 12

what is a proto-oncogene

Answer 12

Genes that normally help cells grow and divide to make new cells and when mutated can cause cells to become cancerous.

Question 13

What is an oncogene

Answer 13

term given to genes which when mutated or are over expressed can cause cancer.

Question 14

Describe the phases of the cell cycle

Answer 14

M phase: mitosis and cytokinesis

G0 Resting cells

G1 RNA and protein synthesis req’d for s phase

S phase DNA synthesis

G2 RNA and protein synthesis required for Mitosis and cytokinesis

Question 15

what are the different parts of M phase

Answer 15

within the mitosis stage before cytokinesis there are 4 stages

Prophase,
metaphase,
anaphase,
telophase

Question 16

describe the prophase stage

Answer 16

the chromosomes condense while centrosome assemble with the nuclear membrane begins to break down

Question 17

describe the metaphase stage

Answer 17

the chromosomes align and attach to the spindle

Question 18

describe the anaphase stage

Answer 18

chromotids pull apart and migrate to poles

Question 19

describe telophase stage

Answer 19

chromotids de condense and new nuclear membrane forms

Question 20

describe the four stages of mitosis and what happens during cytokinesis

Answer 20

During prophase the chromosomes condense and the centrosome assemble. The nuclear membrane then begins to break down before metaphase begins.

The chromosomes then align and attach to the spindle as anaphase causes chromotids to pull apart and migrate the chromosomes to poles of the cell

the telophase then occurs which involves the chromotids de condensing and new nuclear membrane forms before cytokinesis

cytokinesis is the act of a contractile pinching and dividing the mother and daughter cell before entering into g0 of the cell cycle.

Question 21

Describe the 6 hallmarks of cancer

Answer 21

Self sufficiency in growth signals - losing the need for growth factors. This often due to a change in the receptor or signaling pathway.

Insensitivity to growth inhibitors - cells lose the ability to control abnormal cell proliferation which may result from the loss of tumour suppressor genes e.g. pRB or the upregulation of positive cell cycle regulators.

evading apoptosis - under normal conditions it is triggered in cells by dna damage and infection and are avoided through the gain of function of pro survival factors.

limitless replicative potential - under normal conditions cell proliferation limited by telomere length. In tumor cells they can rebuild their telomeres using the enzyme telomerase.

sustained angiogenesis - an increased level of angiogenesis provides blood to the tumor to keep the

tissue invasion and metastasis - metastasis is the spread of he cancer to different sites.

Question 22

Describe how mutation of the RAS oncogene can lead to continuous cell proliferation

Answer 22

In the presence of growth signals RAS (oncogene) is activated and triggers other signaling events that lead to cell proliferation.

When it is mutated it is switched on all the time leading to a constant proliferation even in the absence of a growth factor

Question 23

What are some other notable oncogenes

Answer 23

BCR-ABL
myc
SRC
PI3 Kinase
RAS

Question 24

Name 3 Tumour suppression genes

Answer 24

pRB,p53 BRCA

Question 25

Explain how cancer can cause us harm

Answer 25

Cancer can cause us harm through 3 methods

Disrupting organ function
Interfering with metabolic processes
Muscle wasting

Cancers can disrupt organ function through obstructing them, depriving them of nutrients or apply unwanted physical pressure

Cancers can disrupt metabolic processes by causing malnutrition or calcium changes,

by disrupting the production of blood cells or hormones

and through interfering with the liver enzyme function

Question 26

Describe why cancer can take a while to develop

Answer 26

A single mutation is not enough to lead to the progression of cancer

in actuality a cell will need to undergo multiple mutations to gain most of the hallmarks of cancer in order to progress

Question 27

Define what a mutation is

Answer 27

A mutation is a change that occurs to DNA, there are multiple types of mutation that alter the DNA sequence e.g. point mutation, alteration and deletions

Question 28

Name the 5 different types of mutation

Answer 28

Point mutations, insertions and deletions can occur in gene coding regions

Alterations in transcription/splicing

Amplification/deletions of chromosomal regions

Chromosomal trasnlocations

DNA modification e.g. methylation

Question 29

describe what factors can cause mutations

Answer 29

UV + other radiation

Free radicals

Viruses

Chemicals

Repair errors

Question 30

what cancers are affiliated with the papovavirus family

Answer 30

warts
carcinoma of the uterine cervix

Question 31

what cancers are affiliated with the hepadnavirus family (hep b and c)

Answer 31

liver cancer

Question 32

what cancers are affiliated with herpesvirus

Answer 32

burkitts lymphoma
nasopharyngeal carcinoma

Question 33

what cancers are affiliated with the retrovirus family

Answer 33

t cell leukemia and lymphoma

kaposi’s sarcoma

Question 34

what are the three stages of cancer

Answer 34

initiation where the first mutations promoting a increased proliferation occurs

promotion in which additional mutations promote further proliferation

initiation and promotion are part of carcinogenesis (process of developing a cancer)

progression which sees the growth and the invasion of a tumour

Question 35

Describe why survival rates are improving amongst cancer patients

Answer 35

Earlier diagnosis attribute to a higher survival rate through better screening and scanning for biomarkers

Better treatments through surgery,chemo and radiotherapy

Question 36

what are some risk factors for cancer

Answer 36

smoking
lack of physical activity
obesity
alchohol
diet
infection