chapter 11 cancer biology Flashcards
define cancer
unregulated and abnormal proliferation of cells
What causes cancer?
- mutation caused by genetic aging
what are the two types of cancers
- maligant
- benigine
Malignant cancers are
- invasive
- poorly differentiated
- have a high refractive index
- non encapsulated
- metastasize
- grow rapidly
- originate from cells
benigine cancers are
-non-invasive
- well differentiated
- low miotic index
- well encapsulated
- do not metastasize
- slow growth
- originate from tissue
examples of benign cancer
lipoma
leiomyoma
meningioma
Examples of malignant cancers are
- leukemia—- blood-forming cells
- lymphoma —-lymph tissue
- sarcoma—-mesenchymal tissue
- carcinoma—-epithelial tissue
adenocarcinoma—-duct or glandular tissue
carcinoma in situ
is a pre-invasive epithelial tumor that has not escaped the basal membrane of the epithelial tissue
- can metastasize or disappear all together
What are the three stages of cancer?
- tumor initiation
- tumor promotion
- tumor progression
Tumor initiation is —
the formation or initiation of cancer cells
Tumor promotion is
expanding in the population of cancer cells
tumor progression is
process that leads to spread of the tumor to adjacent and distal sites ( metastasis)
what are the main four classification of hallmarks of cancer
- primary genomic alteration
- secondary genomic alteration
- tumor resistance to destruction
- culmination of other hallmarks
primary genomic alteration include
- sustained proliferative signaling
- evading growth suppression
- genomic instability
- replicative immortality
sustained (continuing) proliferative signaling is
- is uncontrolled cellular proliferation
contains mutated or overexpressed proto-oncogenes - causes autocrine stimulation of growth factors
- activates oncogenes which causes point mutation in RAS gene converts from regulated to unregulated
- gene amplification
- excess and inappropriate production of a proliferation factor
- promotion of growth promoting proteins
