Hi, You can download the normalized expression value from the protein atlas, or on TCGA. On TCGA webportal itself you can create a hiearchial cluster of genes of your interest or you can also download the RNA expression value for genes of your interest from human protein atlas database. Important thing, all depend on the condition in which you want to check. Expression can change depend on the situation. Another thing is you can create corrleation network for genes of your network after downloading the expression counts. It will give you better idea, whether their expression is corrleated among themselves or not.