Facilitator Questions

1. Why is there unlikely to be a single, “magic bullet” cure for cancer?
   


2. Mutations in genes that normally function to promote cell proliferation can cause cancer. These are called oncogenes. For example, mutations in the Ras oncogene can allow for constitutive growth factor signaling and the inappropriate cell proliferation characteristic of tumors. Conversely, mutations in genes that normally function to restrict proliferation can also cause cancer. These are called tumor suppressor genes. An example is Retinoblasoma (Rb), which normally functions to prevent excessive cell growth by inhibiting cell cycle progression. How must the nature of mutations in oncogenes and tumor suppressor genes differ, in order for both groups to promote tumor growth?
   


3. If a person inherits a heterozygous mutation in the tumor suppressor gene APC, they still have one functioning, normal copy of this gene. However, all of these individuals develop colon polyps, and nearly all go on to develop colon cancer at a young age (in the absence of treatment). How does this occur?
   


4. Why does cancer tend to be more prevalent in elderly populations than among the young?
   


5. Anoikis is a type of apoptosis (programmed cell death) that takes place when normal integrin-based cell attachments are lost. How might anoikis contribute to cancer progression?