GLUL and non-proliferative diabetic retinopathy: After differentially expressed proteins being identified between all groups, it was possible to found that 10 proteins (CALML3, CALML5, GLUL, SET/SETSIP, APOBEC3A, CTSL, GLRX, NAMPT, ABHD14B, and PDIA3) were common among NPDR and PDR, when performed a comparison between each diabetic subgroup to the control group or in multiple comparison, and 13 proteins are common to NPDR and PDR groups (Figure 4B).