"Onco-questions"
Final questions for the course.

1. Are oncogenes normally in human chromosomes, or are they only brought in by oncoviruses? If the former, how come there aren't more cases of cancer?

   

2. Are there cancers of all human tissues? Are some never involved because of some sort of selectivity? If an onco virus infects a brain cell and a brain tumor results, would that same virus produce liver cancer were it to have infected a hepatic cell? What about metastasis - if a brain tumor cell metastasizes to the liver, does it result in a liver tumor, or in a transposed brain tumor?

   

3. Why do isolated places, such as the mountain areas in Tennessee, have higher melanoma rates than other areas of the United States?

   

4. Cancers of primary and secondary sexual tissues (ovaries, breasts; prostate, testes) have a total equal percentage (about 42%) in both males and females, and are the most common cancers. Why these tissues?

   

5. A retrovirus has only three genes plus one optional other one. The optional onc-gene can be in two diferent places in the viral genome - at the end, or in the middle of the "pol" gene. What kind of difference can this make? How can the second one survive?