4. Personalised Cancer medicine Flashcards
(54 cards)
what does heterogeneous mean?
a tumour is made up of more the 1 cell type with different mutations.
why are heterogeneous tumours bad?
they present an obstacle to treatment
are all tumour heterogenous?
no but most are especially metastatic tumours
why is relapse much more likely in heterogeneous tumours?
because not all cells in the tumour are killed by the treatment and the remaining cells can repopulate the tumour
why do we need personalised medicine?
current cancer treatment doesn’t account for the individual tumour and are broad specturm medicines
what current broad spectrum cancer treatments do we use?
drugs that target mitosis like taxol
these still have a role but they don’t differentiate between normal and tumour cells very well.
tumour cells are more susceptible to these treatments due to fast replication
what can personalised treatment do?
it accounts for specific mutations and can target them
each patient can have tailored treatment for their tumour with less side effects
what is an example of personalised cancer treatment?
if a tumour has BCR-ABL mutation specific drugs can be used to target it
what is BCR-ABL mutation?
it is a fusion protein made by chromosomal translocation from chromosome 9 and chromosome 22
it phosphorylates things that are not normally
what can effect different tumour biomarkers?
genetic and epigenetic factors
what 2 cell types are all breast cancers derived from?
- luminal epithelial cells
- basal cells
what are the differences between luminal derived cancers and basal derived cancers?
- they responsed differently to signals
- they responsed differently to treatments
- basal cell cancers are normally receptor negative
what is basal luminal cell cancer?
a intermediate stage of cancer that tend to still have high levels of HER2 expression
what are 40% of luminal cancers?
Estrogen and progesterone receptor positive
what is triple negative breast cancer?
it makes up 15-20% of breast cancer
poor prognosis
Estrogen, progesterone and HER2 receptor negative
not as responsive to treatment
what does HER2 over expression lead to?
can be well treated with specific drugs
what happens in estrogen receptor positive breast cancer?
- estrogen stimulates receptors
- activation of transcription factors
- causes cell proliferation
how can we treat estrogen receptor positive breast cancer?
- tamoxifen blocks the binding of estrogen to the receptor
- prevents the cell proliferation signals
- used as a treatment to prevent cancer cell proliferation
what is the HER2 receptor?
a tyrosine kinase that activates a number of kinase pathways
what can the HER2 tyrosine kinase pathways influence in the cancer cell?
- adhesion
- differentiation
- cell growth
- migration
- apoptosis
how can we prevent HER2 signalling pathway stimulation?
using monoclonal antibodies like trastuzumab
what are the BRCA proteins involved in?
DNA repair
what happens in DNA repair in normal cells?
there are lots of different DNA repair mechanisms and if one doesnt work then the other pathways can compensate
what happens in BRCA1/2 DNA repair in tumour cells?
- either BRCA1 or BRCA2 pathways will be lost to start the cancer cell
- the cell is mutated enough that only 1 repair pathway left
- if we block the remaining repair pathway we can kill the cancer cells as the DNA becomes too damaged to replicate and survive
