Bevacizumab and ranibizumab on microvascular endothelial cells: A comparative study

Abstract

Given its broad effects in endothelium, vascular endothelial growth factor (VEGF) represents the primary rate-limiting step of angiogenesis. Therefore, VEGF targeting therapies were soon developed. Bevacizumab and ranibizumab are two of these therapeutic agents already in clinical use. Bevacizumab was first used for cancer treatment, whereas ranibizumab was designed to target choroidal neovascularization, the main cause of blindness in age-related macular degeneration. The present study aims to compare the multiple effects of bevacizumab and ranibizumab in human microvascular endothelial cells (HMECs). HMEC cultures were established and treated during 24 h with the anti-VEGF agents within the intravitreal-established concentration range or excipients. Analyses of VEGF content in cell media and VEGF receptor-2 (VEGFR-2) expression in cell lysates were performed. No cell cytotoxicity (MTS assay) was found in anti-VEGF-treated cultures at any concentration. Apoptosis (TUNEL assay) was significantly increased and cell proliferation (BrdU assay), migration (transwell assay) and assembly into vascular structures were significantly reduced by incubation with both agents at the two doses used. These findings were accompanied by a strong decrease in VEGF release, and in phosphorylated VEGFR-2 and Akt expression for both agents at the clinical concentration. Interestingly, phosphorylated Erk was only significantly reduced upon bevacizumab treatment. In addition, proliferation was more affected by ranibizumab, whereas migration, capillary formation, and phosphorylated VEGFR2 expression were significantly reduced by bevacizumab as compared to ranibizumab. Therefore, although both agents presented anti-angiogenic actions, distinct effects were exerted by the two molecules in HMEC. These findings suggest that a careful confirmation of these effects in clinical settings is mandatory.

Binding and neutralization of vascular endothelial growth factor (VEGF) and related ligands by VEGF Trap, ranibizumab and bevacizumab

“…Consistent with the high potency of VEGF Trap to neutralize VEGF receptor activation, VEGF Trap was highly effective at blocking HUVEC migration induced by VEGF-A 165 . In agreement with previous reports [38, 54], ranibizumab and bevacizumab were also effective at decreasing HUVEC migration, though they were less potent than VEGF Trap, such that a 10- to 100-fold molar excess of ranibizumab or bevacizumab was required to completely block VEGF-induced HUVEC migration, while VEGF Trap was effective at equimolar concentrations.…”

PLGA Microparticles Entrapping Chitosan-Based Nanoparticles for the Ocular Delivery of Ranibizumab

“…Suramin standard, an inhibitor of tubule growth, caused 93 ± 0.3% tubule length inhibition which was similar to a recent study, reporting 90% inhibition (113) . Native ranibizumab has been shown to cause a 50 -70% inhibition of tubule formation at a therapeutic concentration of 125 -200 µg/mL (102,114,115) . This is similar to the ranibizumab used in this study showing an inhibition of 61 ± 4.5%.…”

Preclinical aspects of anti-VEGF agents for the treatment of wet AMD: ranibizumab and bevacizumab

“…In vitro studies in human microvascular endothelial cells demonstrated ranibizumab and bevacizumab to be non-cytotoxic, increase apoptosis, decrease cellular proliferation, migration, vascular assembly and VEGF secretion, and also to decrease VEGF receptor expression and activity. 38 Ranibizumab can reverse VEGF-induced proliferation and migration, and delocalization of tight junction proteins in immortalized bovine retinal cells. 39 It has been demonstrated that at clinical doses, bevacizumab and ranibizumab are equally potent at neutralizing VEGF, and that to neutralize VEGF completely in porcine RPE, a fraction of the clinical dose is needed.…”