Session 9 - Neoplasia 3 Flashcards
What are the 2 types of factors of neoplasia pathogenesis?
Intrinsic and extrinsic
What are 3 intrinsic factors of carcinogenesis?
Heredity
Age
Sex
What are 2 extrinsic factors that cause carcinogenesis?
Environment and behavior
What are the 5 behavioral and dietary risk factors of cancer?
High BMI Low fruit and vegetable intake Lack of physical activity Smoking Alcohol
What are 3 main categories of extrinsic carcinogens?
Chemicals
Radiation
Infection
What is 2-napthylamine?
Industrial carcinogen used in the dye manufacturing industry
What are 2 processes involved in chemical carcinogenesis?
Initiation and promotion
What are 2 examples of mutagenic chemical carcinogens or initiators?
Aflatoxin
Asbestos
What are 2 examples of radiation that are extrinsic carcinogenic factors?
UV
Ionising radiation
How does ionising radiation cause cancer?
Damage DNA
What are 7 microorganisms that cause infections that can be carcinogenic?
Human papilloma virus Epstein Barr virus Hep B virus Hep C virus Human immunodeficiency virus Helicobacter Pylori Parasites
How does HPV lead to cancer?
Expresses E6 and E7 proteins that inhibit p53 and pRB protein function, allowing cell proliferation
How does Hep B and C cause cancer?
Causes chronic tissue injury and the resulting regeneration acts either as promoter for pre existing mutation or cause new mutations from DNA replication errors
What are proto-oncogenes?
Participates in signaling pathways that drives proliferation
What are oncogenes?
Mutations in proto oncogenes and encode oncoproteoms that promote cell growth in the absence of normal growth promoting signals
What are tumor suppressor genes?
Genes that inhibit neoplastic growth
What is the RAS gene?
First human oncogene, encodes G protein that signals the cell to always go past the cell restriction point
What are 3 examples of oncogenes?
Ras
C-myc
HER-2
What are 2 tumor suppressor genes?
Retinoblastoma
P53
What are caretaker genes?
Genes that maintain genetic stability
What are the 3 stages of cancer evolution?
Initiation - cause mutation
Promotion - proliferation
Progression - steady accumulation of multiple mutations
What are 6 hallmarks of cancer?
Self sufficiency of growth signals
Resistance to growth stop signals
Cell immortalisatipn
Sustained ability to induce new blood vessels
Resistance to apoptosis
Ability to invade and produce new metastases
