Molecular Basis of Neoplasia - Nelson Flashcards
What is the key difference between benign and malignant neoplasms
Benign neoplasms cannot spread to other tissues and malignant neoplasms have th capability to metastasize
What four types of mutations cause cancer?
1) Growth-promoting proto-oncogenes
2) Growth-inhibiting tumor supressor genes
3) Genes that regulate apoptosis
4) Genes involved in DNA repair
1) Self-sufficiency in Growth Signals
Proliferate without external stimuli, usually a consequence of proto-oncogene activation (need to lose only one allele)
2) Insensitivity to growth-inhibitory signals
Inactivation of tumor suppressor genes (need to lose both alleles)
3) Altered cellular metabolism
Aerobic Glycolysis (the Warberg effect)
4) Evasion of apoptosis
Resistant to programmed cell death via upregulation of Bcl-2
5) Limitless replicative potential
Immortality (a stem-cell like property)
6) Sustained angiogenesis
Tumor growth necessity
7) Ability to invade and metastasize
Processes that are intrinsic to the tumor cells and signals that are initiated from the tissue environment
8) Ability to evade host immune response
These are the 8 hallmarks of cancer
Define Oncogene
Mutated, overexpressed proto-oncogene
Define Oncoprotein
Mutated protein that can’t be regulated
Define Tumor Supressor Gene
Inhibits cellular proliferation and prevents cell growth; regulates cell cycle, transcription and cellular differentiation; both alleles need to be mutated
Define Proto-oncogene
Only one allele needs to be mutated to cause uncontrolled cell growth and proliferation
Describe the Warburg Effect
Cancer cells use aerobic glycolysis as a form of cellular respiration characterized by high glucose uptaek and increased conversion of glucose to lactose (fermentation)
