TRPC4 and tuberous sclerosis: In the case of three outlier underexpressed DEPs, the protein levels of the first of these, PLCD1 (phosphoinositide phospholipase C; underexpressed DEP with −11.04 FC), and its downstream factor transient receptor potential channel 4 (TRPC4), which colocalize with glutamatergic and GABAergic neurons, were elevated in focal cortical dysplasia type II and tuberous sclerosis complexes, which are well-known causes of chronic refractory epilepsy in children [91].