The Biology Project > Cell Biology > Cell Signaling > Problem Set

Cell Signaling Problem Set

Problem 12: Cancer Therapy

A new drug, STI-571 or Gleevec specifically inhibits the Abl tyrosine kinase that is mutated in chronic myeloid leukemia. Treating patients with the drug dramatically improves survival, but people with a "blast crisis" form of the cancer begin to develop resistance. Which of the following statements are important conclusions from studies on the use of STI-571 in cancer treatment?

A.	Inhibiting signaling pathways can benefit people with cancer.
B.	Rapidly dividing cancer cells that have lost checkpoint systems insuring genome fidelity can develop resistance to specific anti-cancer drugs.
C.	Acquisition of resistance to STI-571 shows that the same specific enzyme changes occur, suggesting that developing new drugs that target mutations leading to resistance may further improve patient survival.
D.	All of the above. Yes, the new results are very promising for some forms of cancer. Many believe this is the first of drugs that target the specific signaling pathways that are altered by mutation in cancer. It will still be necessary to develop treatments for further mutations, especially when the cancer is rapidly dividing and has altered properties.

The Biology Project > Cell Biology > Cell Signaling > Problem Set