B/15 Flashcards
What are the 2 types of carcinogens?
- direct acting carcinogens
- indirect acting carcinogens
Examples of direct acting carcinogens? (4)
- alkylating agents
- nitrogen mustard
- benzyl chloride
- metals
Characteristics of direct acting carcinogens (2)
- acting without metabolic transitions
- weak carcinogens
Characteristics of indirect acting carcinogens (2)
- Metabolic transition is required
- Metabolic transition by cytochrome p450
Steps of chemical carcinogenesis (3)
- Initiation
- Promotion
- Progression
What happens in the promotion step of chemical carcinogenesis? (2)
- mutated clone expansion
- activate protein kinases
What is the promotion step dependant on?
on promotion stimulus
What is the initiation step dependant on?
it is dose dependant
Characteristics of polycyclic aromatic hydrocarbons? (2)
- originate from carbon tar
- cause cancer at the site used
Characteristics of alkylating agents (2)
- come from chemotherapeutic drugs : cisplatin
- transfer alkyl groups on macromolecules to cause DNA damage
Which metals cause carcinogenesis?
bivalent metal cations like Ni2+, Co2+
How do metals cause carcinogenesis?
react with guanine and phosphate groups of DNA
Types of radiation carcinogenesis?
- ionizing radiation
- non ionizing radiation
Which cancers have high vulnerability to ionizing radiation?
AML, CML
Which non ionizing radiation is carcinogenic?
UV-B
