Cell Signalling and Oncogenes Flashcards Preview

SSC- Biology of Cancer > Cell Signalling and Oncogenes > Flashcards

Flashcards in Cell Signalling and Oncogenes Deck (81)
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1

What do cells respond to?

Specific chemicals that signal them to divide 

2

What do the pathways for cell signalling utilised by cells have in common? 

They all display the same fundamental characteristics 

3

What do all signalling pathways involve? 

  • Chemical messenger
  • Receptor
  • Cellular response

 

4

What is signal transduction? 

Essentially, the transmission of a signal from the outside of a cell to the nucleus 

 

5

What can the signal transduced from the outside of the cell to the inside result in? 

Alterations in cell metabolism, gene transcription, and/or cell shape 

6

What does alteration in gene transcription lead to? 

Changes in protein expression 

7

What are proto-oncogenes? 

Genes coding for proteins that help regulate cell growth and differentiation 

8

In what physiological process are proto-oncogenes fundamental? 

Homeostasis 

9

What happens to proto-oncogenes in malignancy? 

They become activated to an oncogene due to mutations, or increased expression 

10

Where is oncogene activation an important mechanism? 

In human cancers 

11

What are the types of mutations that can cause cancer? 

  • Deletion 
  • Insertion
  • Substitution
  • Amplification 
  • Translocation 

 

12

What can be deleted in mutations? 

  • Base pair(s)
  • Genes
  • Chromosomes 

 

13

What can be inserted in mutations? 

  • Repeats of base pair(s)
  • Novel insertions
  • Viruses

 

 

14

What can be substituted in mutations?

Base pairs . 

15

What can be amplified in mutations? 

  • Genes
  • Regions
  • Chromosomes

 

16

What can be translocated in mutations? 

Chromosomes 

 

17

What kind of proteins are encoded for by oncogenes?

  • Growth factors
  • Growth factor receptors
  • Protein kinases/proteins that activate protein kinases
  • Proteins that control the cell cycle 
  • Proteins that affect apoptosis 
  • Transcription factors 

 

18

What do growth factors do? 

Stimulate cells to divide 

19

Give an example of a growth factor 

PDGF

20

What do growth factor receptors do? 

Transduce signals from the outside of the cell to the inside 

 

21

Give an example of a growth factor receptor

EGF receptor (erbB)

22

Give two examples of protein kinases

  • Src
  • Ras

 

23

Give an example of a protein that activates protein kinases

Raf

24

Give an example of a protein that controls the cell cycle

Cyclin D 

25

Give an example of a protein that affects apoptosis

Bcl-2 

26

Give an example of a transcription factor

Myc 

27

What is the significance of Myc in malignancy? 

It is one of the most commonly altered oncogenes 

28

What are the mechanisms of oncogene activation? 

  • Insertional mutagenesis
  • Chromosomal translocation
  • Chromosomal amplification
  • Point mutation
  • Ras signalling

29

What happens in insertional mutagenesis? 

DNA viruses incorporate a viral oncogene, which is inserted into the host DNA

30

Give two examples of viruses capable of insertional mutagenesis

  • Human papillomavirus 16/18
  • Hepatitis B