Cancer NUTR Flashcards
What is the most significant factor contributing to cancer ?
Aging
What’s the most prevalent cancer in female and in male in CA?
breast and prostate
what is the most deadly cancer in female and in male in CA?
both is lung
def. mutation
- structure change
- in the base pair sequence of DNA
what are two types of mutation
- inherited ( BRCA1–> breast & ovarian cancer)
- exogenous factors
polymorohyisms is
- structure of gene varies among individuals
- weaker (probably silence) but more common than mutation
2 types of epigenetic change and example
- methylation: at the promoter region of tumor suppressor genes
- acetylation: chromatin folding
what is “nutritional genomics and proteomics”?
the interaction between diet and genes and their products
when and what the common modification behaviours occur”nutritional genomics and proteomics”?
epigenomics: protein transcription stage
and post translation modification
what are the top two factors affecting the genetic variability
tobacco
diet 7 obesity
differentiate incidence and prevalence
incidence= new cases Prevalence = all cases
why although breast/prostate cancer are the highest incidence, but they have lower death rate in CA?
they have early sign, so it is easier to monitor and find at early stage
what is the general trend terms of cancer incidence in CA?
after age standardized decreases in M and slightly increases in F
what is the general conclusion in terms of cancer incidence in CA?
Compared to the adjusted data, there is no big change since 1987
what is the general trend terms of cancer mortality in CA? why?
- The mortality is decreased in both gender (after age-adjustment)
- better treatment and diagnosis
what is/are the top deadly cancer(s) [no less than 15%] for pop younger than 29
brain and blood-type cancers
what is/are the top deadly cancer(s) [ no less than 10%] for pop older than 30
*30-49: breast, lung and colorectal
50+: lung
what is/are the top deadly cancer(s) for pop older than 30
*30-49: breast and lung
50+: lung
what is the trend of death due to in terms of aging?
from young to old, more and more (increased prevalence)
what is the general trend of cancer incidence in developed vs developing countires? any exception (2+1)?
- higher incidence in developed countries
- yes. Liver cancer and oesophagus cancer (in female, + cervix cancer)
what is descriptive study addressing diet and cancer? what’s the limitation?
- compare the cancer rate in population with different diets
- just for general hypothesis, b/c there are many viarables
what is case-control study addressing diet and cancer? what’s the limitation?
- compared the diets between the cancer pt’s (previous) and the control’s (no cancer)
- possible recall bias and selection bias
- hard to measure rapidly fatal cancers
what is prospective cohort study addressing diet and cancer? what’s the limitation?
- incidence of cancer is compared in people whose diet (or other factors) is determined before follow-up begins
- the cost of time and money would be high. It would be a large sample size with very long timeline. it is hard for rare types of cancer.
what is interventional study addressing diet and cancer? what’s the limitation?
- incidence of cancer in 2 groups randomised to specific interventions is compared
- adherence is difficult
- hard to keep the blinding
- may involve the ethical issue of dosage, etc
rank the 4 studies strength of association (diet & cancer)
D C P I
which type of study can really establish the causal relationship between the diet and cancer development
interventional
three types of common research methods
FFQ
biomarker
systemetic review & meta-analysis
when is more susceptible period to cancer?
fast growth periods:
conceptus to fetus, pre-puberty
adult height reflects ___
pre-adult nutrition
adult weight reflects ___
positive energy balance later in life
why saying the taller people may expose to higher risk of cancer?
taller = better pre-adult nutrition = more susceptible to breast and colon cancer
why saying the women with earlier menarche may expose to higher risk of breast cancer?
early menarche = good nutrition during pre-puberty= more susceptible to cancer
F/T obesity to the female increases risk of breast cancer
F
only after menopause
what are top 3 cancers associated with obesity in the female
- breast (post-meno)
- corpus uteri
- colon
CN women from 65 counties vs US women–> fat & breast cancer: What’s type of study?
prospective
fat intake & breast cancer: conclusions (3)
- no association between fat intake and breast cancer
- one study: positive study between animal fat intake and breast cancer
- low-fat diet does not helpful
T/F High fat intake is associated with high risk of cancer
F
colon cancer
fat intake & colon cancer: conclusion (1)
maybe more relate to excess energy intake => ++ weight, – PA
Meat vs colorectal cancer: conclusion (2) & mechanisms respectively
red meat + colorectal cancer risk (+12-17%, 100g/day): 1) heme promotes formation of N-nitroso compounds 2) cooking methods: generate poly-cyclic aromatic hydrocarbons & hetero-cyclic amines
processed meat + colorectal cancer(25g/day, + ~49%): preservatives–> nitrates, salt
T/F choosing lean lean to prevent the cancer
unknown
no recommendation yet
Pt Mr. XO: so do I have to stop eating red meat b/c of the increased risk of cancer?
You:__
Not necessary. Based on the original risk of cancer to general people, which is low, the increase is very small.
T/F animal products in general diet usually increases the risk of cancer
F:
consumption of milk and dairy products inversely associates with colon cancer.
T/F Eating a lot F/V is a very good way to prevent cancer
T but the evidence in epidemiological studies is not very strong. Prospective studies found a weak association.
Dietary fibres vs cancer: conclusion
- high fibre intake, low rate of colon cancer
Dietary fibres vs cancer: mechanism
dilute or bind potential carcinogens, limit contact w/ mucosa, serve as a substrate to flora producing short-chain fatty acids
EtOH vs cancer: conclusion(2) and mechanisms
- it causes upper-GI cancer and liver, especially combined with cigarette smoking:
direct contact and toxicity in the liver - increase risk of breast an colon cancer: anti-folate effet of EtOH in methyl-poor diet
Ca vs cancer: conclusion and mechanism
Ca intake - colon cancer risk: binding toxic secondary bile acids and ionized FAs (prevent reabsorption), reduce proliferation and induce apoptosis in mucosal cells
Vitamin D vs Cancer: conclusion(2)
- interest generated by observations of low risks of breast, colon and prostate CA in pop. w/ greater sun exposure
- also might be important to limit cancer progression
T/F vitamin D intake is the main evidence that are generally inversely related to the cancer
F
Circulating level of 25(OH)D is the main evidence that are generally inversely related to breast, prostate and colon cancer. Data for other types of cancer are less consistent
Vitamin C, E and selenium vs Cancer: conclusion
- potential have antioxidant effect that can lower the risk
- but epigenetic studies and interventional trials trials did not show a support role to cancer risk
folate vs Cancer: conclusion (2)
- lower the risk of colon, breast and cervical cancer
- supplementation does not support the beneficial role
T/F folate supplements benefit the one with colon cancer
F
it can be harmful b/c it may incr. the recurrence of adenomas
beta-carotene vs Cancer: conclusion
- intake of supplments –> null or increase the risk in smokers and and other adverse effects especially when combined with EtOH
