SLC1A7 and breast cancer: These findings were quite remarkable, because (1) expression of EAAT2 is thought to be restricted to only some BC types and (2) although it is well accepted that EAAT2 and EAAT5 coexist in rod and cone photoreceptors, co-expression of EAAT2 and EAAT5 in any certain type of BCs rarely has been reported in previous studies.