Gen Path Final - Tobacco Flashcards
__________ chemicals (xenobiotics) are absorbed through inhalation, ingestion, or skin contact
Exogenous
Exogenous chemicals can be _________ through exhalation or cause local damage (direct-acting) and/or absorption into blood and distributed throughout body
eliminated
Many exogenous chemicals are _________, requiring metabolism to a water-soluble product (detoxification) and excretion in urine or feces
lipophilic
Some exogenous chemicals are chemically changed to a _________ ___________; this is an indirect-acting chemical
toxic metabolite
1 cause of preventable death in the US
Smoking-related illness
What are the 3 fates of a xenobiotic once it has entered the body?
Storage
Excretion
Toxicity
Xenobiotics that have become toxic have effects on __________ ___________ such as enzymes, receptors, membranes, DNA
cellular molecules
T/F: More than 10x as many people in the US have died as a result of cigarette smoking than have died in all the wars fought by the United States in its entire history
True
Main components of tobacco
Nicotine
Formaldehyde
CO
> 60 carcinogens
Which component of tobacco?
Basis for addiction, not carcinogenic
Nictoine
Which component of tobacco?
Toxic to cilia
Formaldehyde
Which component of tobacco?
Causes hypoxia
CO
Which component of tobacco?
2 biggest groups are polycyclic aromatic hydrocarbons + nitrosamines
Carcinogens
What are the 2 key steps of carcinogenesis?
Initiation
Promotion
Initiation or promotion?
Tobacco’s chemicals form adducts mainly w/ DNA (covalently bound)
Initiation
Initiation or promotion?
If unrepaired, DNA replication predisposes to mutation; oncogenes (RAS) + tumor suppressor genes (p53) are common targets
Initiation
Initiation or promotion?
Do not cause mutations, but they induce cell proliferation of initiated/mutated cells
Promotion
Initiation or promotion?
Increased division of mutated cells predisposes to new mutations that can lead to cancer formation
Promotion
Initiation or promotion?
Examples: hormones, drugs, chronic inflammation
Promotion
What is associated with the following cancers?
Lung, oral, laryngeal, esophagus, stomach, pancreas, kidney, bladder, cervix, bone marrow, liver, colon
Tobacco smoke
Relative cancer risk is dose dependent, increasing with ________. Expressed as pack-years. Packs smoked each day multiplied by number of years smoking
time
T/F: There is a multiplicative/synergistic risk of cancer from cigs when combined with alcohol
True