aging and disease lecture 5- cancer 2

Question 1

what are the hallmarks of cancer?

Answer 1

eight, acquired, functional capabilities that allow cancer cells to survive, proliferate and disseminate
First proposed by Hanahan and Weinberg in 2000

Question 2

what are the emerging hallmarks of cancer in 2011?

Answer 2

-deregulating cellular energetics
-avoiding immune destruction

Question 3

what are the first hallmarks of cancer?

Answer 3

-resisting cell death
-sustaining proliferative signalling
-evading growth suppressors
-activating invasion and metastasis
-enabling replicative immortality
-inducing angiogenesis

Question 4

what are the enabling characteristics of hallmarks?

Answer 4

-genome instability and mutation
-tumor promoting inflammation

Question 5

how do cancer cells evade growth suppressors?

Answer 5

the signals to stop the proliferation fail

Question 6

what does tumour suppressor inactivation cause in cancer cells?

Answer 6

means that cellular proliferation is unchecked and cellular defence mechanisms no longer function

Question 7

how is enabling replicative immunity occur?

Answer 7

-In normal cells telomeres progressively shorten with each cell division
-In most cancer cells there is an increase in activity of telomere-extending enzyme telomerase
-Cancer cells acquire unlimited replicative potential: cellular immortality

Question 8

what is telomere shortening?

Answer 8

-In normal cells telomeres progressively shorten with each cell division
-Apoptosis can be initiated

Question 9

what does the presence of telomerase in cancer cells allow?

Answer 9

allows them to maintain telomere length while they proliferate

Question 10

what is angiogenesis? and why do cancer cells need this process?

Answer 10

Angiogenesis is a normal process in growth and development, as well as in wound healing.
Cancer cells require new blood vessel formation to survive and grow: angiogenesis is switched on

Question 11

what regulates hundreds of genes that induce angiogenesis?

Answer 11

Hypoxia-inducible transcription factor (HIF) system eg VEGF

Question 12

how do cancer cells activate invasion and metastasis?

Answer 12

Carcinomas developed alterations in shape as well as in their attachment to other cells

Question 13

what are stats about cancer treatments

Answer 13

-50% survive cancer for 10 or more years
-cancer survival in the uk has doubled in the last 40 years
-there is a huge variation in survival between cancer types

Question 14

what are cancer treatments?

Answer 14

Conventional-
surgery
radiation therapy
chemotherapy

Alternative-
gene therapy
Antiangiogenesis
Targetted chemotherapy

Question 15

what can cancer therapies target?

Answer 15

Drugs targeted at pathways, processes and physiology which are uniquely disrupted in cancer cells:
Receptors
Genes
Angiogenesis
There should be few side effects since these therapies are specifically targeted to cancer cells

Question 15

what is anastrozole?

Answer 15

they are drugs that can halve breast cancer risk offered to 289,000 women in England
they block oestrogen production by inhibiting aromatase

Question 16

what is the HER2 gene and what’s its relationship to breast cancer?

Answer 16

HER2 gene amplification or receptor overexpression occurs in ~ 25% of metastatic breast cancers

HER-2 Oncogene: amplified and overexpressed in 20-25% of breast cancer

HER2 positive tumours are associated with poor prognosis and shortened survival

HER2 receptor provides an extracellular taret for novel and specific anti cancertreatment using monoclonal antibodies

Question 17

what is Herceptin?

Answer 17

anti-HER2 antibody
attaches to her2 receptors and may stop them signalling the cell to grow
Targets HER2 oncoprotein
High affinity and specificity

Question 18

what is the relationship between tamoxifen and cancer?

Answer 18

1- Oestrogen molecule binds to estrogen receptor
2-Oestrogen receptor acquires changed shape
3-Oestrogen receptor binds to co-oactivators
4-Tamoxifen molecule binds to oestrogen receptor
5-Tamoxifen receptor does not acquire changed shape
6-Tamoxifen receptor cannot bind to co-oactivators

Question 19

read screenshot of how hallmarks of cancer cells are caused