In-vivo models Flashcards
What are ways to create in vitro models?
2-D plates
3-D flask
spheroid
What is the difference between 3D and 2D models?
3D- It’s mimics microenvironment can see drug resistance, intercats with ECM, cell cell contact, diffusion gradient
What is the matrix made up of? How does it work?
Sodium alginate beads, calcium and chitosan.
Alginate beads promote metastasis
True
What is the downside of using invivo models?
Sfety
long time
variation of tumours/low intake rate
What’s the difference between transgenic mouse and mutant mouse?
For mutant it sponateously arises for transgenic a tumour promiting gene is deliberately introduced
What is a must when using rodents as models?
They have to immunodeficient
Does different cell lines have a different response even though same cancer?
Yes
Why doesn’t in vitro models mimic real life tumours envirnoment?
Because there is an increase in cell cycle in established cell lines it’s unregulated which doesn’t necessarily mimic all of the cells in the patient, it takes a lot of time for cancer to develop in the patient versus in vivo
How can micoenvrionment mimic the real one?
Stromal interaaction
hypoxia relevant vasculature
epithelial to mesenchymal transition
cancer stem cells
Why is vascularation important in models?
Because t predics chemo and radio therapy sensitivity
influences drug delievery
mesenchymal trasnition will also be modelled
potentitiates development of CSC
induce VEGF expression
Why is stromal interaction important? How is it modelled?
Because it protects the stem cell niche
injecting human tumour derived fibroblasts, differntiating mesenchymal cells with stromal cells
ECM supplements
How do we add CSC to the model?
We can enrich for these cells in vitro and then study their expansion
What would be a good experimental for studying cancer?What are some challenges should we should focus on to create the perfect model?
Using clinically equivilant doses combination studies resistant cell lines Treatng primary cell lines Timinig of administration, single therapy, levels of drugs and pharmokinetics have to be achievable in patients
How is timing important when administerating the therapy?
The models should have the cancer stage as humans, not early on because in patients alot of cancer is detected at the metastaic stage, findings will be more representative.
What is a way where tumours can mimick the environment?
XENOGRAFT orthotopic transplantaion
How is imaging done for animals?
Optical
How do optimal reporters work? What are the positives and negatives of using it? What are the 2 kinds? What can be used instead to make up for limited luminescence?
Hydrolyzes ATP uses sugar and oxygen Fast, non invasive limted depth, not transfereble to clini, limited useful luminescence fluorescence and luminescence Multispectral technology
How can we model metastasis?
By removing primary tumour-spontaneous
Explain metastatic bone tumour
There is an increase of osteoclasts and osteoblasts whencancer metastasizes there which will increase osteoclasts and osteoblasts leading to lytic lesion and hardening of the bones which will lead to malformation and weakened bones
Metastasis from the same primary tumour responds differently to the same drugs
true
What are ways to insert drug and optical reporter in models?
injection
tracheal implantation via cannula
surgical implantation
iv injection
What are the quantum dots? What is good about it?
They are semi conductors noncrystals with fluorescence probes. They are photostable, many colours, greater depth, accuracy, efficient the higher the wavelength the less teh signal absorption, can detect below infared and after infared
How is signal detected in fluorescence? What is the ratio of quantum efficiency between emission and excitation?
The distance between excitation and emission
1
How are dual reporters injected in cells and what processes do they monitor?
Lentiviral vector mediated delivery and liposome mediated techniques.
Apoptosis, p53 expression, calcium signalling, stem cell morkers
What are problems with quantum dots?
Energy dramatically decreases as the wavelength increases
needs laser and supercooled cameras
What is animal scientific procedures?
It regulates any experiment done to a protected animal that can hurt them, any living vertebrae or immature animals
