Drug Delivery Flashcards
What is cancer?
Cells have the ability to divide.
The rate of that division is controlled by external cues.
Cancer results when mechanisms in cells that regulate division lose control
How do cell division rates vary?
Embryo - every 20 minutes
skin - 12-24 hours
liver - every year or so
How do rates of cancer change with age?
when 0-4, 31% of cases are leukaemia and 25% are CNS, drops to 13% and 18% respectively when 15-19
What is stage 1 cancer?
small invasive mass found, no spread from areas
What is stage 2 cancer?
Starting to spread to nearby tissues, and/or lymph nodes, mass may be slightly larger
What is stage 3 cancer?
Greater effect on surrounding tissues and/or lymph nodes, mass grown further
What is stage 4 cancer?
Metastatic cencer that has spread to lymph nodes and other tissues/organs
How does cancer kill?
Via metastatic cancer
- primary sites can be ressected
- in severe stage 4, patient dies from metastatic burden n=and primary site remains unidentified
- cancer will have hallmarks of original cell tyoe, which defines the likely metastatic behaviour
What are the common preferential spread sites?
Lung to brain, bone and adrenal
Melanoma to brain
Breast to bone brain lung and liver
Pancreatic to lung and liver
Why are humans so susceptible to cancer?
poor genetics: Somatic defects, epigenetics
humans and viruses: transposable elements, proto-oncogenes
hyper-mutatable genone
Epigenetics in oncology
- variations in outcome between patients
- epigenetics can alter outcoems for indentical twins
Epigenetic treatments
What are writers?
Add modifications
Epigenetic treatments
What are erasers?
removal of post-translocational modifications
Epigenetic treatments
What are readers?
Detecting modifications
Epigenetic treatments
What are movers?
Shifting a histone modification to another DNA region
Epigenetic treatments
What are shapers?
mutation of a histone protein itself that alters function
Epigenetic treatments
What are insulators?
boundaries lost by mutation
How do tumours develop?
- uncontrolled growth
- breakdown in normal mechanisms of checkpoints that regulate cell growth
- a disease of self, immune system doesnt react
What are the hallmarks of cancer?
- Avoiding immune destruction
- Enabling replicative immortality
- Tumour promoting inflammation
- Activating invasiona nd metastasis
- Inducing angiogenesis
- Genome instability
- Resisting death
- Evading growth supressors
Cancer and age
- primaroly a disease of old age
you need 3 mutations to devlop cancer, most have 7 by diagnosis
tissues with higher turnover rates have increased rates of cancer
