Exam #1: Obesity, Energy Balance & Cancer Flashcards
How do food and nutrition lead to the development of cancer?
Food & nutrient availability influences genetic material within cells
What are the six hallmarks of cancer?
1) Growth signal autonomy
2) Evasion of growth inhibitory signals
3) Evasion of apoptosis
4) Unlimited replication
5) Sustained angiogenesis
6) Invasion and metastasis
Describe the broad dietary problem of our age.
Overnourished macroscopically; undernourished microscopically
What is the relationship between metabolic syndrome & cancer?
Inflammatory state of metabolic syndrome/ obesity promotes genetic instability
What does nutrient excess lead to the production of?
ROS, which creates oxidative stress that can damage cell structures
Generally, what are the three maladaptive responses to nutrient excess?
1) ROS
2) Impaired ER giving rise to unfolded proteins
3) Accumulation of long-chain fatty acids
Why is chronically elevated insulin bad?
Insulin is associated with cell growth, carcinogenesis, & tumor promotion
Serum levels of what hormone are associated with poor prognosis of many cancers?
Insulin or C- peptide
Describe the mechanism by which hyperinsulinemia leads to carcinogenesis.
- High insulin= upregulation of IGF-1 (liver)
- IGF-1 suppresses apoptosis & initiates cell cycle progression from G1 to S-phase
What is the association between VEGF & obesity?
VEGF (angiogenesis) is produced by both adiopocytes & tumor cells
At the cellular level, what is the cellular composition of obesity?
Macrophages surrounding necrotic adipocytes
What study in mice demonstrated the role of obesity in tumor growth?
- Tumor cells transplanted into under fed and overfed mice
- Underfed had slower growing tumors
What hormone links post-menopausal breast cancer & obesity?
Increased ESTROGEN production via adipocytes
What proportion of cancers are related to being overweight, obese, or physical inactivity?
1/3
What is the largest “medical disaster” of the past 100 years?
Low fat/ high carbohydrate diet
*Food pyramid 1974