How can the phenotypic effects of a tumor suppressor mutation be silenced?
This is more of a comment



Mutation in tumour suppressor is a recessive trait and there is no active "silencing" of the mutation. If a tumour suppressor is a TF then a mutation in the DNA binding domain can have no effect if there is a complementary mutation in its binding site. This is just a theoretical possibility and I have not heard of any examples as such. I don't think any other mechanisms exist for "silencing" any loss of function mutation.