Carcinogenesis & Genotoxicity deel 2 Flashcards
What are differences between benign and malignant neoplasms?
benign
- non invasive
-highly differentiated
- mitosis rare
-slow growth
-no metastasis
malignant
-invasive
-poorly differntiated
-mitosis common
-rapid growth
-metastases
What are 3 steps in metastasis?
- detachment of tumor cells
- attachment to matrix cells
- degradation of extracellular matrix
What is the 1 cause of cancer?
lifestyle: smoking and diet
What are other causes of cancer?
chemicals, DNA viruses, radiation, genetics, fibers
What are some chemical carcinogens?
- polycyclic aromatic hydrocarbons (PAH, PAK)
- aromatic amines
-mycotoxins
-alkylating agents
Hoe kan Benzopyrene een mutatie veroorzaken?
Benzopyrene is een PAH. Door metabolisme komen er groepen aan benzopyrene die kunnen binden aan DNA
Wat is een bron van Polycyclic aromatic hydrocarbons? (PAH) en op welke orgaan richten ze zich?
-roken
-uitlaatgassen
-vuur
-huid en longen
Wat is een bron van aromatic amines en op welk orgaan richten ze zich?
roken
verbrand vlees
kleurstoffen
aromatic amines = blaas
heterocyclic = darmen
What are carcinogenic mycotoxins?
-toxins produced by fungi
-secodary metabolites
What is aflatoxin?
-Mycotoxin
-found in moldy products, spices, milk, eggs
-category 1 carcinogen
How are carcinogens metabolized?
from procarcinogen to ultimate carcinogen
phase 1:activate or detoxify
phase 2: make metabolite more polar so it can be exctreted.
What gene can affect cancer susceptibility differences?
CYP = Cytochrome P450
What is chemoprevention?
The use of substances
to stop or prevent
cancer development
What causes promotion of iniated cells?
-repeated injury
-viruses
-hormones
-surgery
-chemicals
What is the difference between genotoxic and non-genotoxic tumor?
Genotoxic is caused by a carcinogen
non-genotoxic is caused by spontaneous DNA damage
Which 4 genes are involved in carcinogenesis?
- Proto-Oncogenes
- Tumour Suppressor genes
- DNA Repair genes
- Apoptosis regulating genes
What are Proto-Oncogenes?
-accelerators of cell division
-stop for apoptosis
-dominant allel
What are Tumor Supressors?
-inhibitors of cell division
- HELP for apoptosis
-recessive allel
What is a mutation?
Alteration in the genetic code, that may result in altered population of cells or
organisms.
What are mutagens:
chemicals that cause a mutation
What is the role of mutations?
-adaptation/survival/speciation
-disease/death
What are possible effects of mutations in genes?
-no effect
-change in gene expression
-change in protein structure
-disease
-altered cell function
-improper biochemical process
What are examples of genotoxic factors?
UV light
radiation
virusus
biotoxins
chemicals
What is ANEUPLOIDY?
loss or addition of extra copy of chromosome
What are three types of human Carcinogens?
Physical; uv, radiation
Biological; virus
Chemical
