MAP KINASES /ERK
THE MAP KINASES OR MITOGEN ACTIVATED PROTEIN KINASE WHICH WE SPOKE ABOUT RECENTLY AS THEY RELATE TO PANCREATIC, RENAL, AND BRAIN TUMORS,
are downstream from the Epidermal Growth Factor (EGFR) pathways.  When speaking about a pathway,  it is  like a dance where A will dance with B,  A will flirt with B, and B will then leave A and go dance with C and flirt again, and C will the move to D and Flirt and so on.  With each Flirting, there is an exchange of all kinds of things including emotions (and I am not kidding) . Down this pathway is found Molecule involved with Schizoaffective disoders such as bipolar state.  The Actual Pathways is as follow:

EGF--EGFR--GRB2--SOS (My favorite Sons Of the Sevenless) which switch on or excite RAS--RAF--MEK--MAPK (our MITOGEN Activated Protein) which switch a number of Molecules depending on location including MYC and the action goes into the Nucleus to stimulate transcription genes and production of growth proteins.

At each flirt contact, we can intervene and spoil the moment with a Target therapy.
At RAS-RAf we can spoil it by sending Sorafenib or Vemurafenib and treat lung cancer.
At the Raf-MEK, we can send in Selumetinib or Trametinib to inhibit MEK and so on.

At each level, the flirting is actually a chemical reaction mostly involving phosphorylation.  Spoiling the language of phosphorylation is achievable but the challenge is that even normal cells uses this language so it is hard to be selective.  Altering phosphorylation will affect many other normal functions of cells including energy production.  This is an area of intense investigation. It would be a lack of respect if we did not of memtion EGFR inhibition which is the main action in treatment of many important cancer from Head and neck to lung, colon, gastric and so on so forth. And you know the drugs!