文档介绍：Cancer – What is it?
What is the difference between a benign tumor and a malignant tumor?
What is the difference between a sarcoma and a carcinoma?
Cancer forms most commonly in what tissues?
What are some common mechanisms thought to “cause’ cancer?
Are some types of cancer more “curable” than others?
True/False?
Most cancers are derived from a single abnormal cell
Most cancers develop due to a single mutation in a cell’s DNA
Name at least three key properties that make cells capable of cancerous growth.
Tumors are generally traced to a single cell that has undergone a heritable change that gives it the ability to outgrow its neighbors.
Detectable at about a billion cells or more
Due to a genetic change (mutation) or an epigenetic change?
Genes from maternal or paternal side, can influence the production or inhibition of other genes.
Normal incidence of mutation:
10-6 mutations per gene per cell division
Lifetime accumulation of mutations:
1010 mutations in each gene
So Why Isn’t Cancer More Common?
Tumors may progressively accumulate mutations
They may grow sporadically, increasing in size when a particular advantageous mutation gives a cell a selective advantage over its neighbors
Tumors may also regress if advantageous mutations do not occur and the existing cells cannot survive in the environment they create
What characteristics give cancer cells an advantage?
Genetic instability
Defective control of cell death or cell differentiation
Loss of proliferation controls
Ability to survive in an alien environment
Proto-oncogenes
Tumor suppressor genes