I was given the following as an example for a quiz question but i don't understand the answer. Any help will be most welcome:
Question: Iressa is a Tyrosine Kinase Inhibitor. As a young oncologe, to whome of the patients will you recommand not to take this treatment:
a. Biopsia has shown that the EGF receptor is mutant
b. Biopsia has shown that the RAS protein is mutant
c. Biopsia has shown that the MAP Kinase stays in the nucleuous permanently
d. The treatment can help each of a,b,c, cases.
The right answer should be a. Can someone see why and help here?
I know that tyrosine kinase receptor is the inside part of the EGF receptor (where the two monomeres become a dimer and phosphorelate each other). So, if the EGF receptor is mutant, shuldn't it help inhibiting it's continuation inside the cell and thus prevent to many EGF cascades?