I searched, but didn’t find a recent post labelled Genomic testing to use as a dumping ground. My apologies if I missed something!
Anyway, here is the summary from Foundation One.
Genomic Alteration CDKN2A/B loss
The CDKN2A gene encodes 2 different, unrelated tumor suppressor proteins, p16INK4a and p14ARF. p16INK4a binds to and inhibits CDK4 and CDK6, thereby maintaining the growth-suppressive activity of the Rb tumor suppressor; loss or inactivation of p16INK4a contributes to dysregulation of the CDK4/6-Cyclin-Rb pathway and loss of cell cycle control.. The tumor suppressive functions of p14ARF involve stabilization and activation of p53 via a mechanism that involves MDM2 inhibition. Loss of CDKN2A ablate both p16INK4a and p14ARF. CDKN2B encodes the p15INK4b tumor suppressor, which functions similarly to p16INK4a. Promoter methylation of CDKN2A/p14ARF, CDKN2A/p16INK4a, and CDKN2B has been reported in 25-40% 50-76%, and 49-50% of cholangiocarcinomas respectively.
A bit more detail…
Because proteins encoded by CDKN2A and CDKN2B inhibit Cdk4……… May be sensitive to CDK4/6 inhibitors……… Tumors with p14ARF loss or inactivation may also be sensitive to MDM2 inhibitors.
There are trials underway, which may be beneficial… And one of these is for breast cancer patients, so there is funding for the trial. Dr. D is fairly excited about this trial in particular.