Introduction to Cancer Flashcards
What is Cancer?
A name for a group of diseases characterized by:
- Abnormal Cell proliferation
- Tumour formation
- Invasion of neighbouring normal tissue
- Metastasis
What increases risks to developing cancer?
- Smoking
- Alcohol
- Obesity and Weight
- Hormones
- Sun and UV
- Infections and HPV
- Air pollution and radiation
- Inherited genes
What reduces risk of cancer?
- Physical activity
- Diet and Healthy eating
What are carcinomas?
Cancer that occurs in epithelial tissue
What are sarcomas
Cancers in mesoderm cells( Bone and Muscle)
What are adenocarcinomas
Cancer found in glandular tissue
What is cancer a disease of?
Age- More mutations in the body over time
What is surveillance?
Recognition of cancer cells by the immune system
What are the two types of mutation?
Germline mutation and Somatic mutation
What is germline mutation?
Mutation in the egg or sperm cell and is inheritable.
It increases the risk of developing cancer
What is Somatic Mutation?
Mutation in cells in a tissue. Non inheritable but can be passed onto daughter cells.
What is the initiation of the development of cancer?
Clonal
How do tumours evolve
Sub clonal Selection which allows for a growth advantage and heterogeneity of cells
What are the consequence of evolved tumours
Resistance to treatments
What are 4 types of carcinogens
Chemical, Physical, inherited, Viral
How is there a balance of cell numbers
Balance in cell division and apoptosis
What can affect the balance in cell numbers
Mutations in genes that regulate the pathway of division and apoptosis.
What are proto-oncogenes?
A normal gene activated to be oncogenic. They stimulate growth and division in a cell.
What is a mutated proto oncogene called?
An oncogene
What are tumour suppressor genes?
Genes that inhibit growth and tumour formation. They act as braking signals during G1 before S phase in the cycle.
What happens if a tumour suppressor gene is mutated?
No normal break and there will be uncontrolled growth of a cell.
What do normal cells require to divide?
Growth factors?
What are cancer cells not dependent on?
Growth factors, they have mutated to allow uncontrolled growth.
What do normal cells respond to?
Inhibitory signals.
How do cancer cells evade growth suppressors?
They have mutations which interfere with these inhibitory pathways.
What happens when a tumour evades the immune system?
The tumour enters a stage of cancer progression and forms a clinically detectable cancer
How does the immune system work to prevent cancer?
Eliminated pathogens such as tumour inducing viruses, and identifies and eliminates tumour cells (Immune surveillance)
