Nutrition and cancer Flashcards
What are the 5 types of cancer?
Carcinoma, adenocarcinoma, sarcoma, leukemia, lymphoma
What types of DNA damage mechanisms can be induced by genotoxic carcinogens?
point mutations, deletions and insertions, recombinations, rearrangements, amplification, chromosome aberration, DNA adducts
Genotoxic = \_\_\_components Non-genotoxic = \_\_component
Genotoxic = Microcomponents Non-geno = Macrocomponents
Give some examples of toxic microcomponents
- Heterocyclic amines
- Polycyclic aromatic hydrocarbons
- N-Nitrosamines
- Aflatoxin B1
- Alcohol
What food product are heterocyclic amines found in?
What do they do in vivo?
Found in muscle meets at high cooking temperatures (bbq etc)
They form adducts with DNA bases and induce nitrnium ions -> bind to guanine and alter DNA sequence
How are heterocyclic amines formed (biochemically)
Pyrolysis of proteins/amino acids/creatine
What are the target organs of heterocyclic amines?
Stomach, oesophagus, colon, breast, prostate
1) What is the genetic influence of HCA’s?
2) What are the activating enzymes?
3) What are the detoxifying enzymes?
1) Genetic polymorphisms in the genes that encode metabolizing enzymes for HCA activation or detoxificaion
E.g. NAT1, NAT2, GSTM1, GSTT1, SULTA1
2) Cyt P450 (CYP1A2), N-acetyl transferase
3) N-acetyl transferase (NAT2)
How are N-Nitrosamines formed?
Binding of Nitrites and Nitrates to amino acids
What does the GCP nutraceutical stand for and what is it’s medical use?
Genistein combined polysaccharide
Anti-cancer, anti-inflammatory, anti-angiogenesis
What nutraceuticals have been tested for coronary heart disease?
Soy protein (genistein)
Stanol/sterol esters
Omega-3 oil
B-glucans
What is the role of vitamin E in prostate cancer?
What are the food sources of vitamin E
Tocopherols and Tocotrienols?
Mitochondria-triggered intrinsic apoptosis (pro-apoptotic)
Tocopherols: nuts & vegetable oils
Tocotrienols: palm oil, oat, rye, wheat, rice bran
What is the role of lycopene in preventing prostate cancer?
It is a cartotenoid antioxidant
Most efficient cartoenoid for scavenging oxygen radicals and interferes with cancer cell signalling
found in tomatoes
What is the role of soy and isoflavones (found in tofu) in prostate cancer?
They are phytochemicals
Activa component - genistein
Genistein inhibits the enzyme tyrosine kinase - pro-apoptotic, inhibits prostate cancer cell growth
What is the major catechin in green tea?
Epigallocatechin-3-gallate (EGCG)
What are the common mechanisms of chemoprevention? (8)
Inhibit cell signalling Anti-angiogenesis Anti-invasive Pro-apoptosis Anti-proliferative Anti-inflammatory Anti-oxidative Anti-tumour
What are some potential problems with nutraceuticals?
Only 1% tested Contradictory information Interactions unknown Oral bioavailability Metabolism Specific tissue targetting
What are the different types of nanoparticles? (4)
Polymer
Dendrimer
Liposomal
Iron oxide
What cancer does poppy seeds, basil leaves and cumin seeds reduce?
squamous cell carcinoma
Why is there increased risk of oral and oesophagael cance in india?
Reverse smoking and Paan chewing Salted tea with sodium bicarbonate Sundried veg and chillies (high nitrosamine content) Kalakhar from banana skin
What is in deep fried vegetables and salted/sun-dried fish that can cause cervical cancer?
polycyclic aromatic hydrocarbons
What are the components of a traditional Mediterranean diet?
high monounsaturated to saturated lipid ratio
- high fruit consumption
- high vegetable consumption
- high legume consumption
- high cereal consumption
- moderate-to-high fish consumption
- low-to-moderate milk/dairy consumption
- moderate ethanol consumption
2-point increase in an Mediterranean Diet score associated with __% reduction in overall cancer mortality
2-point increase in an MD score associated with:
24% reduction in overall cancer mortality
