Cancer Chemoprevention Flashcards
Cure is better than prevention, true or false?
False, prevention is better than cure
What percentage of patients can be cured of cancer?
~50%
Once cancer has occurred, what can be the downsides to treatment?
It may be unpleasant, ineffective and extremely expensive
Who do cancer treatments impact?
Patients
Families
Society
Give an example of how cancer cells can induce angiogenesis
Through the production of VEGF
Give an example of how cancer cells can activate invasion and metastasis
Though the inactivation of E-cadherin
Give an example of how cancer cells can cause tumour-promoting inflammation
Through COX overexpression
Give an example of how cancer cells can enable replicative immortality
By turning on telomerase
Give an example of how cancer cells can avoid immune destruction
By infiltrating tumour-promoting inflammatory cells
Give an example of how cancer cells can evade growth suppressors
Through the loss of the Rb suppresssor
Give an example of how cancer cells can sustain proliferative signalling
Through the activation of Ras oncogenes
Give an example of how cancer cells can deregulate cellular energetics
By increasing glycolysis
Give an example of how cancer cells can resist cell death
Through the production of IGF survival factors
Give an example of how cancer cells can acquire genomic instability and mutations
Through an increase in mutation rate
What are the 4 biggest causes of cancer?
Tobacco
Diet
Overweight and obesity
Alcohol
What are the eight recommendations to decrease cancer risk?
- Be as lean as possible without becoming underweight
- Be physically active for at least 30 minutes every day
- Avoid sugary drinks and limit consumption of energy-dense foods (particularly process foods high in sugar, or low in fibre, or high in fat)
- Eat more variety of vegetables, fruits, wholegrains and pulses such as beans
- Limit consumption of red meats and avoid processed meats
- If consumed at all, limit alcoholic drinks to 2 for men and 1 for women a day
- Limit consumption of salty foods and food processed with salt (sodium)
- Don’t use supplements to protect against cancer
Define chemoprevention
Use of natural or synthetic compounds to reverse, suppress, prevent or delay carcinogenic progression to invasive cancer
What should the ideal chemopreventative agent have?
High efficacy No or low toxicity Known mechanism(s) Acceptance by humans Oral formulation Low cost
Define blocking agents
Compounds which inhibit carcinogenesis by preventing carcinogens from being generated or from reaching, or reacting with, critical target sites in tissues
Define suppressing agents
Compounds which act after carcinogenic exposure by suppressing the expression of neoplasia
What would the use of surrogate endpoint biomarkers allow?
Smaller trials, quicker assessment of efficacy without waiting for tumours
What would the use of surrogate endpoint biomarkers require?
A detailed understanding of the cancer process in any given tissue
A detailed understanding of the mechanism of action of the chemopreventive agent
What percentage of high risk women saw a reduction in breast cancer after treatment with tamoxifen?
38%
Tamoxifen has no real adverse effects, true or false?
False, it can have serious adverse effects including endometrial cancer and venous thromboembolic events
During the development of cancers, at what stages are there opportunities for prevention?
Between a cell changing from normal to hyperproliferating
Between an adenomatous polyp changing from small to large
Between a pre-cancerous polyp to an adenocarcinoma
