Lecture 1 - Tumorigenesis and Hallmarks Flashcards
A benign tumour is
- a growth that is confined to a specific site within a tissue and gives no evidence of invading adjacent tissue
- an epithelial growth that has not penetrated through the basement membrane
- require little treatment
A malignant tumour is
- a growth that shows evidence of being locally invasive and possibly even metastatic
- Less well differentiated cells and grow and divide rapidly
- More difficult to treat
What are the 4 main types of cancer
- carcinoma
- sarcoma
- leukaemia
- lymphoma
What is a carcinoma and the types
- a cancer of epithelial tissues in internal and external linings
- Adenocarcinoma - develop in an organ or a gland
- Squamous cell carcinoma - from squamous epithelial organs
Examples of Adenocarcinoma
Breast, lung, liver, colon prostate etc
Example of squamous cell carcinoma
skin, oesophogus, lung oral
Names of the benign carcinomas
Adenocarcinoma - adenoma
Squamous cell carcinoma - papilloma
What is leukaemia
Cancer of the blood originating in the bone marrow
What is a lymphoma
Cancer of the lymphatic system (lymphocytes)
The basic 4 steps in progression of cancer in the skin
- Hyperplasia - where cells proliferate more
- Dysplasia - where cells morphologically change such as nuclei
- Carcinoma in situ
- Invasive carcinoma
What is a CIS
Carcinoma in situ
- Cells grow in uncontrolled but are contained at the moment
- have a high potential to become invasive
Subtypes of lung cancer and their occurrence
Small cell lung cancer 15%
Non small cell lung cancer 85%
- Lung Adenocarcinoma
- Lung Squamous cell carcinoma
- Large-cell carcinoma
Majority of cancers are due to which type of mutations
Somatic mutations
Only 5-10% are germline mutations
Cancer progression evolution can be described as
Branched rather than linear
How is cancer metastasis potential determined?
- Clonal selection theory
- Predetermined genetic predisposition theory
- The host predisposition theory
Overview of clonal selection theory
- Metastasis is a late event in cancer progression
- Some cells mutate over time allowing them to metastasise
Overview of predetermined genetic predisposition
- The metastatic potential of a cancer is predetermined into early tumours
- Able to predict from the beginning of a tumour whether it has the ability or not to metastasise
- Due to the genotype
Overview of the host predisposition theory
- Factors such as single polynucleotide morphisms may increase the likelihood of metastasis
- Tumours arising in individuals with a certain host genotype have a higher probability of metastasis
Aspects of the tumour microenvironment
- Endothelial cells
- Lymphocytes
- Macrophages
- Cancer-associated fibroblasts
- ECM
