Shen Y, et al. - Researchers conducted this cross-sectional study to ascertain vitreous and serum levels of high mobility group box-1 (HMGB-1) in patients with proliferative diabetic retinopathy (PDR) and illustrate their connection with receptor for advanced glycation end products (RAGE), vascular endothelial growth factor (VEGF) and interleukin-1β (IL-1β). Study participants with PDR who had vitrectomy were enlisted and the control group involved non-diabetic eyes. ELISA analyzed vitreous and serum samples for HMGB-1, RAGE, VEGF and IL-1β. A positive correlation was found between serum and vitreous levels of HMGB-1 in patient with PDR. A negative correlation was noted between serum and vitreous levels of VEGF in patient with PDR. The finding indicates the existence in PDR of a pro-inflammatory and angiogenesis state as demonstrated by higher concentrations of HMGB-1, RAGE, VEGF and IL-1β in both the vitreous and serum. HMGB-1 could contribute to the cross-talk connections between angiogenesis and inflammation and could be a novel therapeutic objective for inhibiting PDR progression.