Tumour Biology Flashcards
What is Cancer ?
An uncontrolled proliferation of cells
How many cells do we have ?
37.2 trillion
How badly your body regenerates?
Every 7 years
What do cells do and what do cancer cells do ?
Cells divide continuously to replace damaged or dead cells. There are control mechanisms to regulate cellular growth rate and differentiation.
In cancer, these mechanisms fail and cells grow without control and without a useful function, leading to unchecked growth that progresses toward limitless expansion
In average how many mutations make a cancer cell ?
Six
Why is cancer potentially dangerous ?
because it can spread through your body
What are the Properties of Beningn Tumour ?
Slow - Growth Rate
Expansion -Character of Growth
Remains Localized - Tumour Spread
Well Differentiated - Cell Differentiated
What are the properties of Malignant Tumour ?
Rapid - Growth Rate
Character of growth - Infiltration
Tumour Spread - Metastasis
Cell Differentiation - Poorly differentiated
how many mutations does it take to make a cancer cell?
6
What is Replaced with what ?
The cells lining the stomach are replaced every five days.
-Cells in the epidermis last about a week.
-Red blood cells live for four months
. -Hepatocytes live for about five months.
- A bone completely remodels itself and replaces all of its cells every ten years or so.
- Cells in the intestinal tract and certain muscles last for about fifteen years.
- Cells that rarely—if ever—turn over: oocytes, cardio myocytes and neurons.
Why do cells continue to divide ?
Cells divide continuously to replace damaged or dead cells.
There are control mechanisms to regulate cellular growth rate and differentiation.
In cancer, these mechanisms fail and cells grow without control and without a useful function, leading to unchecked growth that progresses toward limitless expansion
Examples of Normal Growth : The skin ( The epidermis)
The epidermis is roughly a dozen cells thick, cells in the bottom row of this layer (the basal layer) divide to replenish the cells shed from the surface of the skin
Every division produce a basal cell (to maintain the basal layer) and another cell that loses the capacity to divide and migrates out of the basal layer.
Examples of Cancer growth : The skin ( the epidermis )
During skin cancer, the basal cells divide faster than is needed to replenish the cells being shed from the surface of the skin.
Each time one of these basal cells divides, the two newly formed cells will often retain the capacity to divide
Regardless of the growth rate, tumors ultimately increase in size until the normal organization of the tissue gradually becomes disrupted.
What is Apoptosis ?
Is the death of cells which occurs as a normal and controlled parts of an organism growth or development they are form of programmed cell death .
Which help remove cells during development , eliminating any cancerous or virus infected cells /maintains balance in the body .
What is Malignant ?
They are tumours that may invade its surrounding tissues or spread around the body .