Biology - Stem Cells and Cancer

What is cancer

group of diseases where cells divide uncontrollably.

Occur bc of mutations in DNA that control checkpoints, errors not found/dealt with and tumours form

Benign VS Malignant tumour

Tumour = Abnormal growth of tissue, can develop anywhere at any stage of life

• Benign: Non cancerous

  • encapsulated and easy to remove

  • only puts pressure on surrounding tissue

• Malignant: Cancerous

  • not encapsulated, hard to remove

  • interferes with neigbouring cells and can lead to organ failure

Metastasis

Process of cancer cells breaking away from primary tumour (where it first develops) and establishing secondary tumour elsewhere in body. Travels through bloodstream

2 types of stem cells

Embryonic Stem Cell = Pluripotent, differentiate into many types of cell

Tissue/Adult stem cell = exist within specialized tissue, are unipotent, only differentiate into cell of tissue it came from

3 sources of stem cells + their pros and cons

Embryo - can be created by therapeutic cloning

• pros = unlimited growth potential, can be obtained from IVF programs

• cons = higher tumour risk, can only be obtained through destroying an embryo

Cord Blood - umbilical cord / placenta of newborn

• Pros = lower tumour risk, easily obtained and stored

• Cons = reduced growth potential, limited quantities available, umbilical cord is removed at birth and discarded whether stem cells harvested or not, only becomes different types of blood cells

Adult Tissue

• pros = lower tumour risk, adult patient can give extraction permission

• cons = reduced growth potential, difficult to obtain bc very few and buried very deep in tissue

Whats a stem cell, whats its use? Differentiation?

Stem Cells = Unspecialized cells that can continuously divide and replicate, and have capacity to differentiate into specialized cell types

Differentiation = process where newly formed cells become more specialized and distinct from one another as they mature, by chemical signals activating specific instructions on their DNA

Specialized cell and levels

A cell that can perform a specific function

Totipotent - differentiates into ANY type of cell

Pluripotent - MANY types of cell

Multipotent - FEW CLOSELY RELATED types of cell

Unipotent - can regenerate, only differentiate into ASSOCIATED cell type