Role of Epiregulin in Lung Tumorigenesis and Therapeutic Resistance.

Epidermal growth factor (EGF) signaling regulates multiple cellular processes and plays an essential role in tumorigenesis. Epiregulin (EREG), a member of the EGF family, binds to the epidermal growth factor receptor (EGFR) and ErbB4, and it stimulates EGFR-related downstream pathways. Increasing evidence indicates that both the aberrant expression and oncogenic function of EREG play pivotal roles in tumor development in many human cancers, including non-small cell lung cancer (NSCLC). EREG overexpression is induced by activating mutations in the EGFR, KRAS, and BRAF and contributes to the aggressive phenotypes of NSCLC with oncogenic drivers. Recent studies have elucidated the roles of EREG in a tumor microenvironment, including the epithelial-mesenchymal transition, angiogenesis, immune evasion, and resistance to anticancer therapy. In this review, we summarized the current understanding of EREG as an oncogene and discussed its oncogenic role in lung tumorigenesis and therapeutic resistance.

Transferrin Receptor-Targeted Iduronate-2-sulfatase Penetrates the Blood-Retinal Barrier and Improves Retinopathy in Mucopolysaccharidosis II Mice.

Mucopolysaccharidoses (MPSs) make up a group of lysosomal storage diseases characterized by the aberrant accumulation of glycosaminoglycans throughout the body. Patients with MPSs display various signs and symptoms, such as retinopathy, which is also observed in patients with MPS II. Unfortunately, retinal disorders in MPS II are resistant to conventional intravenous enzyme-replacement therapy because the blood-retinal barrier (BRB) impedes drug penetration. In this study, we show that a fusion protein, designated pabinafusp alfa, consisting of an antihuman transferrin receptor antibody and iduronate-2-sulfatase (IDS), crosses the BRB and reaches the retina in a murine model of MPS II. We found that retinal function, as assessed by electroretinography (ERG) in MPS II mice, deteriorated with age. Early intervention with repeated intravenous treatment of pabinafusp alfa decreased heparan sulfate deposition in the retina, optic nerve, and visual cortex, thus preserving or even improving the ERG response in MPS II mice. Histological analysis further revealed that pabinafusp alfa mitigated the loss of the photoreceptor layer observed in diseased mice. In contrast, recombinant nonfused IDS failed to reach the retina and hardly affected the retinal disease. These results support the hypothesis that transferrin receptor-targeted IDS can penetrate the BRB, thereby ameliorating retinal dysfunction in MPS II.

Effective treatment with mepolizumab in a patient with severe eosinophilic granulomatosis with polyangiitis complicated with small intestine perforation.

Eosinophilic granulomatosis with polyangiitis (EGPA) is systemic vasculitis caused by eosinophilia affecting small to medium-sized blood vessels, which damages the organs. Antineutrophil cytoplasmic antibody-associated vasculitis EGPA treatment guidelines added anti-interleukin-5 antibody mepolizumab to the standard treatment protocol for active-non-severe EGPA based on the MIRRA study. Nevertheless, the role of mepolizumab in treating patients with active severe EGPA has not been established. We treated a patient with EGPA complicated with small intestine perforation using steroid pulse intravenous, high-dose glucocorticoids, intravenous high-dose immunoglobulin therapy, and mepolizumab without immunosuppression agents; the patient went into remission, suggesting that mepolizumab is an effective therapeutic agent that could lead to remission in severe EGPA.

Effect of triamcinolone acetonide on retinal inflammation and angiogenesis induced by pericyte depletion in mouse.

Triamcinolone acetonide (TA) has been shown to improve morphological and functional outcome in diabetic macular edema (DME) patients. However, the functional mechanism of TA has not been elucidated yet. In this study we investigated the detailed functional mechanism of TA using culture cells and retinopathy mouse models in which retinal inflammation and abnormal angiogenesis were induced by pericyte depletion. TA significantly prevented retinal hemorrhage, edema and partially improved abnormal angiogenesis. TA decreased retinal vascular endothelial growth factor (VEGF) concentration, presumably by preventing recruitment of macrophages into retina and TA also inhibited expression of inflammatory cytokines in retina. TA inhibited proliferation/migration of vascular endothelial cells and vessel sprouting. No direct inhibition of VEGF receptor 2 (VEGFR2) autophosphorylation was observed by TA. These results suggested that TA improved inflammatory retinal events which were induced in pericyte-deleted mice by mainly decreasing macrophage-derived VEGF and expression of inflammatory cytokines followed by attenuation of vascular permeability and proliferation/migration of endothelial cells. Furthermore, in these processes, translocation of glucocorticoid receptor (GR) was partially involved.

A pregnant woman with severe dyspnoea.

Preterm delivery is a feasible option in the third trimester of pregnancy in the treatment of pregnant women with acute respiratory distress syndrome due to miliary tuberculosis with respiratory failure https://bit.ly/3stKOzj.

Randomized phase 2 study comparing irinotecan versus amrubicin as maintenance therapy after first-line induction therapy for extensive disease small cell lung cancer (HOT1401/NJLCG1401).

BACKGROUND: A cisplatin plus irinotecan (CPT-11) regimen is used for patients with extensive disease small cell lung cancer (ED-SCLC). Amrubicin (AMR) is primarily used for relapsed SCLC. The HOT1401/NJLCG1401 trial, an open-label randomized phase II trial, was designed to assess the benefit of maintenance therapy in patients with ED-SCLC who responded to induction therapy. METHODS: Patients with histologically- or cytologically-confirmed ED-SCLC were included and were treated with an induction therapy of four cycles of cisplatin (60 mg/m2 on day 1) plus CPT-11 (60 mg/m2 on days 1, 8, and 15) every four weeks. After induction therapy, patients who had nonprogressive disease were randomized to receive either maintenance CPT-11 (60 mg/m2 on days 1 and 8) every three weeks, or AMR (35 mg/m2 on days 1-3) every three weeks. RESULTS: A total of 34 patients were enrolled; 20 patients had progressive disease or received incomplete induction chemotherapy. Finally, 14 patients were randomly assigned to receive CPT-11 (n = 7) or AMR (n = 7). This study was terminated prematurely because of low patient accrual. The overall objective response rate was 73%, the median PFS was 5.7 months (95% confidence interval [CI]: 3.6-11.8), and the median overall survival was 20.1 months (95% CI: 13.7-not reached). No statistically significant difference in progression-free survival (PFS) were noted between patients treated with CPT-11 and those treated with AMR. There were no treatment-related deaths in this study. CONCLUSIONS: Maintenance therapy with CPT-11 or AMR after induction therapy might be effective in some patients.

Excess adiponectin in eyes with progressive ocular vascular diseases.

Anti-vascular endothelial growth factor (VEGF) therapies are now the first-line treatment for many ocular diseases, but some patients are non-responders to these therapies. The purpose of this study was to determine whether the level of adiponectin increased the pathogenesis of retinal edema and neovascularization in the retina of progressive ocular vascular diseases. We examined the role played by adiponectin in two types of cells and animal models which are retinal vein occlusion (RVO) and oxygen-induced retinopathy (OIR) mice. Our results showed that an injection of anti-adiponectin antibody ameliorated the retinal edema and ischemia through the depression of the expression level of VEGF-related factors and tight junction-related proteins in the retina of RVO mice. The intravitreal injection of anti-adiponectin antibody also decreased the degree of retinal neovascularization in an OIR mice. In addition, exposure of human retinal microvascular endothelial cells and human brain microvascular pericytes in culture to adiponectin increased both the vascular permeability and neovascularization through the increase of inflammatory factor and the dropout of the pericytes. These findings indicate that adiponectin plays a critical role in retinal edema and neovascularization, and adiponectin is a potential therapeutic target for the treatment of diabetic macular edema, proliferative diabetic retinopathy, and RVO.

Effects of progranulin on the pathological conditions in experimental myocardial infarction model.

Progranulin is a secreted growth factor associated with multiple physiological functions in ischemic pathophysiology. However, it is still not fully understood how progranulin is involved in ischemic lesion and cardiac remodeling after myocardial infarction (MI). In this study, we investigated the effects of progranulin on myocardial ischemia and reperfusion injury. We investigated progranulin expression using Western blotting and immunostaining after permanent left coronary artery (LCA) occlusion in mice. Infarct size and the number of infiltrating neutrophils were measured 24 h after permanent LCA occlusion. Recombinant mouse progranulin was administered before LCA occlusion. In addition, we evaluated cardiac function using cardiac catheterization and echocardiography, and fibrosis size by Masson's trichrome staining after myocardial ischemia/reperfusion in rabbits. Recombinant human progranulin was administered immediately after induction of reperfusion. Progranulin expression increased in the myocardial ischemic area 1, 3, and 5 days after permanent LCA occlusion in mice. The administration of recombinant mouse progranulin significantly attenuated infarct size and infiltrating neutrophils 24 h after permanent LCA occlusion in mice. We also found that administration of recombinant human progranulin ameliorated the deterioration of cardiac dysfunction and fibrosis after myocardial ischemia/reperfusion in rabbits. These findings suggest that progranulin may protect myocardial ischemia/reperfusion injury.

Successful afatinib rechallenge in a patient with non-small cell lung cancer harboring EGFR G719C and S768I mutations.

Recent studies have indicated that afatinib is beneficial for patients with non-small cell lung cancer (NSCLC) harboring uncommon epidermal growth factor receptor (EGFR) mutations, while the effectiveness of afatinib rechallenge has not been fully defined. Here, we report a long-term survival case of NSCLC harboring concomitant EGFR G719C and S768I mutations who received afatinib rechallenge followed by chemotherapy. The present case suggests that combined therapeutic strategies such as afatinib plus sequential chemotherapy would be beneficial based on appropriately timed rebiopsies from recurrent lesions. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY AND WHAT THIS STUDY ADDS: A NSCLC patient carrying EGFR G719X/S768I mutations survived for a long period of time with afatinib rechallenge followed by chemotherapy. Combined therapeutic strategies should be considered based on rebiopsies in appropriate timing in NSCLC with uncommon EGFR mutations.

Prospective Feasibility Study of Amrubicin and Bevacizumab Therapy for Patients With Previously Treated Advanced NSCLC.

BACKGROUND/AIM: The efficacy of the combination of amrubicin and bevacizumab against advanced non small-cell lung cancer (NSCLC), as a second or third-line treatment, was evaluated. PATIENTS AND METHODS: Amrubicin was administered for 3 days to patients with previously treated advanced NSCLC, whereas bevacizumab was administered on day 1 of each cycle; this regimen was repeated every 3 weeks. RESULTS: Among the 16 patients, an overall response rate of 12.5% (for two patients) was achieved, and the overall disease control rate was 93.7%. Progression free survival and overall survival were 8.5 and 16.6 months, respectively. Grade 3 or 4 haematological toxicities were leukopenia, neutropenia, and febrile neutropenia. Grade 3 proteinuria and infection were the non haematological adverse events. CONCLUSION: The combination of amrubicin and bevacizumab is a promising regimen in the second or third-line treatment for advanced non-squamous NSCLC; however, physicians must recognise the risk of proteinuria related with this regimen.

Administration of docetaxel plus ramucirumab with primary prophylactic pegylated-granulocyte colony-stimulating factor for pretreated non-small cell lung cancer: a phase II study.

PURPOSE: Although docetaxel plus ramucirumab has shown superior treatment efficacy over docetaxel monotherapy for patients with non-small cell lung cancer (NSCLC), the high rate of febrile neutropenia (FN) presents a clinical problem. This study aimed to validate the primary prophylactic use of pegfilgrastim with docetaxel and ramucirumab treatment in Japanese patients with NSCLC. METHODS: Patients with NSCLC with progression after at least one round of chemotherapy were enrolled and administered docetaxel (60 mg/m2) plus ramucirumab (10 mg/kg) intravenously on day 1, followed by pegylated-granulocyte colony-stimulating factor (3.6 mg) on day 2 of a 21-day treatment cycle. The primary study endpoint was the percentage of patients who developed FN. Secondary endpoints included overall survival, progression-free survival, overall response rate, and safety. RESULTS: Overall, 20 patients (15 men and 5 women) were enrolled, of whom one developed FN, resulting in an overall FN rate of 5%. The response and disease control rates were 40% and 85%, respectively. The median progression-free survival was 6.6 (95% confidence interval [CI], 0.5-NR) months. The median overall survival was 18.4 (95% CI, 2.2-11.0) months. Six patients aged over 75 years were included in this study, and although most adverse events were durable, ramucirumab-associated adverse events occurred more frequently in these patients. CONCLUSIONS: We observed a 5% FN rate using primary prophylactic pegylated-granulocyte colony-stimulating factor with docetaxel plus ramucirumab in Japanese patients with NSCLC. While most adverse events were durable, elderly patients should be closely monitored.

Anti-VEGFR2 Antibody-modified Micelle for Triggered Drug Delivery and Effective Therapy of Choroidal Neovascularization.

OBJECTIVE: This study aimed to examine whether DC101 (anti-VEGFR2 antibody)- modified micelles have applications as novel drug delivery devices, which allow small molecule antiangiogenic agents to deliver to angiogenic sites on a murine laser-induced choroidal neovascularization (CNV) model. MATERIALS AND METHODS: CNV was induced by photocoagulation on the unilateral eye of each mouse under anesthesia. Immediately after laser coagulation, E7974-loaded DC101-modified micelles and motesanib-loaded DC101-modified micelles were intravitreally administrated. Two weeks after photocoagulation, CNV was visualized using fluorescein-conjugated dextran (MW=2,000 kDa), and the CNV area was measured in retinal pigment epithelium (RPE)-choroidal flat mounts. RESULTS: Intravitreal administration of both DC101-modified micelles loaded with E7974 at 2 µM and motesanib at 2 µM significantly reduced CNV area in the murine laser-induced CNV model at a clearly lower concentration than the effective dose of each agent. CONCLUSION: These results suggest that DC101-modified micelle might be effective drug carrier system for treating CNV and other ocular angiogenic diseases.

Nrf2 Activator RS9 Suppresses Pathological Ocular Angiogenesis and Hyperpermeability.

Purpose: Ocular angiogenesis, including retinopathy of prematurity, diabetic retinopathy, and exudative age-related macular degeneration, are closely related to oxidative stress. Many reports have shown that the cellular protective mechanism against oxidative stress and inflammatory response has nuclear factor-erythroid 2-related factor-2 (Nrf2) activity. The aim of this study was to investigate the effectiveness and mechanism of Nrf2 activation in treating the ocular diseases with abnormal vessels. Methods: The effects of Nrf2 activators, bardoxolone methyl (BARD) and RS9, were evaluated against vascular endothelial growth factor (VEGF)-induced cell migration in human retinal microvascular endothelial cells (HRMECs). We measured the expression of the Nrf2 target genes, Ho-1 and Nqo-1 mRNA, in mouse retinas after a single injection of BARD and RS9. The effects and mechanisms of RS9 against retinal angiogenesis were evaluated using an oxygen-induced retinopathy (OIR) model in mice. Moreover, the effect of RS9 against choroidal neovascularization (CNV) was evaluated in a laser-induced CNV monkey model. Results: Both BARD and RS9 decreased VEGF-induced cell migration, and significantly increased Ho-1 mRNA expression; however, only RS9 significantly increased Nqo-1 mRNA. RS9 decreased retinal neovascularization through suppressing VEGF expression and increasing Nrf2, HO-1, platelet-derived growth factor receptor (PDGFR)-ß, and tight junction proteins in OIR murine retinas. Furthermore, RS9 showed a tendency toward decreasing CNV lesions, and improved vascular leakage in a CNV monkey model. Conclusions: These data indicate that a Nrf2 activator might be a candidate for treatment of ocular diseases characterized by pathophysiological angiogenesis and hyperpermeability.

Dual inhibition of MEK and p38 impairs tumor growth in KRAS-mutated non-small cell lung cancer.

Despite the high frequency of KRAS mutations in non-small cell lung cancer (NSCLC), therapeutic modalities targeting KRAS-mutated NSCLC have not been established. Based on our previous findings that mutant KRAS knockdown sensitized NSCLC cells to a p38 inhibitor, the growth-inhibitory effect of dual MEK and p38 inhibition on tumor growth in NSCLC cells harboring KRAS mutations was investigated. In KRAS-mutated NSCLC cells, the MEK inhibitor, selumetinib, inhibited cell growth in a dose-dependent manner, and its growth-inhibitory effect was enhanced by combined treatment with the p38 inhibitor LY2228820. Similarly, another pair of MEK and p38 inhibitors also exhibited antitumor activity. Small interfering RNAs (siRNAs) against MAPK14, which encodes p38α MAPK, enhanced the growth-inhibitory effect of the MEK inhibitors in NSCLC cells with KRAS mutations. Notably, MEK inhibitors reduced p38 expression levels but increased p38 phosphorylation levels, resulting in sensitization to p38 inhibitors in KRAS-mutated NSCLC cells. These results provide evidence that dual MEK and p38 inhibition could be a potent therapeutic strategy against oncogenic KRAS-driven NSCLC.

Both Autocrine Signaling and Paracrine Signaling of HB-EGF Enhance Ocular Neovascularization.

OBJECTIVE: The incidence of blindness is increasing because of the increase in abnormal ocular neovascularization. Anti-VEGF (vascular endothelial growth factor) therapies have led to good results, although they are not a cure for the blindness. The purpose of this study was to determine what role HB-EGF (heparin-binding epidermal growth factor-like growth factor) plays in ocular angiogenesis. APPROACH AND RESULTS: We examined the role played by HB-EGF in ocular neovascularization in 2 animal models of neovascularization: laser-induced choroidal neovascularization (CNV) and oxygen-induced retinopathy. We also studied human retinal microvascular endothelial cells in culture. Our results showed that the neovascularization was decreased in both the CNV and oxygen-induced retinopathy models in HB-EGF conditional knockout mice compared with that in wild-type mice. Moreover, the expressions of HB-EGF and VEGF were increased after laser-induced CNV and oxygen-induced retinopathy, and their expression sites were located around the neovascular areas. Exposure of human retinal microvascular endothelial cells to HB-EGF and VEGF increased their proliferation and migration, and CRM-197 (cross-reactive material-197), an HB-EGF inhibitor, decreased the HB-EGF-induced and VEGF-induced cell proliferation and migration. VEGF increased the expression of HB-EGF mRNA. VEGF-dependent activation of EGFR (epidermal growth factor receptor)/ERK1/2 (extracellular signal-regulated kinase 1/2) signaling and cell proliferation of endothelial cells required stimulation of the ADAM17 (a disintegrin and metalloprotease) and ADAM12. CRM-197 decreased the grades of the fluorescein angiograms and size of the CNV areas in marmoset monkeys. CONCLUSIONS: These findings suggest that HB-EGF plays an important role in the development of CNV. Therefore, further investigations of HB-EGF are needed as a potential therapeutic target in the treatment of exudative age-related macular degeneration.

Apolipoprotein E2 and E3, but Not E4, Promote Retinal Pathologic Neovascularization.

Purpose: To determine the relationship between the different isoforms of apolipoprotein E (ApoE) and retinal neovascularization. Methods: The concentrations of ApoE and VEGF in vitreous humor samples with either a macular hole (MH), or diabetic macular edema (DME), or proliferative diabetic retinopathy (PDR) with or without intravitreal injection of bevacizumab (IVB) were measured by ELISA. The effects of each isoform of ApoE on human retinal microvascular endothelial cells (HRMECs) in culture or on the retina of oxygen-induced retinopathy (OIR) mice were investigated. Results: The concentrations of ApoE and VEGF were significantly higher in the vitreous humor of patients with PDR and DME than in patients with an MH. There was a significant positive correlation between the concentrations of ApoE and VEGF in vitreous humor of patients. In vitro assays showed that ApoE2 and ApoE3, but not ApoE4, promoted the VEGF-induced cell proliferation and migration. In vivo assays showed that intravitreal injections of ApoE2 and ApoE3 increased the number and area of nodes in the retina of OIR mice. Moreover, ApoE was expressed in the vascular endothelial cell in both normal and OIR retinas, but their expression levels were different at postnatal day (P) 12 and P17. Conclusions: These results demonstrate that ApoE2 and ApoE3, but not ApoE4, have proangiogenic effects, and the increased expression of ApoE in the vitreous humor of patients with PDR and DME indicates that ApoE2 and ApoE3 are involved in the development of retinal neovascularization in eyes.

Retinal Diseases Associated with Oxidative Stress and the Effects of a Free Radical Scavenger (Edaravone).

Oxidative stress plays a pivotal role in developing and accelerating retinal diseases including age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and retinal vein occlusion (RVO). An excess amount of reactive oxygen species (ROS) can lead to functional and morphological impairments in retinal pigment epithelium (RPE), endothelial cells, and retinal ganglion cells (RGCs). Here we demonstrate that edaravone, a free radical scavenger, decreased apoptotic cell death, oxidative damage to DNA and lipids, and angiogenesis through inhibiting JNK and p38 MAPK pathways in AMD, glaucoma, DR, and RVO animal models. These data suggest that the therapeutic strategy for targeting oxidative stress may be important for the treatment of these ocular diseases, and edaravone may be useful for treating retinal diseases associated with oxidative stress.

Evaluation of gefitinib efficacy according to body mass index, body surface area, and body weight in patients with EGFR-mutated advanced non-small cell lung cancer.

PURPOSE: In patients with epidermal growth factor receptor (EGFR)-mutated, advanced, non-small cell lung cancer (NSCLC), common gefitinib-sensitive EGFR mutations that predict a greater response to therapy include the exon 19 deletion and L858R point mutation. The objective of this study was to evaluate whether body surface area (BSA), body weight (BW), and body mass index (BMI) affect gefitinib efficacy in such patients. METHODS: The medical charts of 138 consecutive patients with advanced NSCLC harboring sensitive EGFR mutations, who underwent gefitinib treatment, were reviewed. The median BSA and BW were used as cutoff values to evaluate their impact on gefitinib efficacy. BMI was categorized as underweight (<18.5 kg/m2), normal (18.5-25 kg/m2), and overweight (≥25 kg/m2). RESULTS: The median BSA and BW were 1.48 m2 and 53 kg, respectively. The overall response rate, progression-free survival (PFS), and overall survival (OS) were 65.2%, 12.2, and 24.2 months, respectively. There were no significant differences in clinical outcomes according to BSA, BW, or BMI alone. Subgroup analysis based on the mutation type and BSA revealed no significant differences in PFS between the groups; however, the median OS in those with exon 19 deletion combined with low BSA was significantly favorable compared with the other groups. CONCLUSIONS: Gefitinib efficacy in patients with NSCLC harboring sensitive EGFR mutations did not differ according to BSA, BW, and BMI. However, OS was superior in patients with both the exon 19 deletion and low BSA.

Topical Diclofenac-Loaded Liposomes Ameliorate Laser-Induced Choroidal Neovascularization in Mice and Non-Human Primates.

This study aimed to evaluate the effect of liposomes loaded with diclofenac, a potent cyclooxygenase (COX)-1 and COX-2 inhibitor, on laser-induced choroidal neovascularization (CNV) in mice and non-human primates (common marmosets). CNV was induced by laser irradiation on the unilateral or bilateral eye of each mouse or common marmoset, respectively, under anesthesia. The CNV was visualized using fluorescence labeling with intravenous injection of fluoresceinconjugated dextran (molecular weight = 2,000 kDa), and quantified in the retinal pigment epithelia (RPE)-choroidal flatmounts. Diclofenac-loaded liposome or diclofenac ophthalmic solution was instillated to the eye surface daily for 14 days and 21 days in mice and common marmosets, respectively. In the mouse CNV model, 0.1% diclofenac-loaded liposome eye drops administered four times a day (q.i.d.) significantly reduced CNV formation in the RPE-choroidal flatmounts compared with those in empty liposome eye drops. Diclofenac-loaded liposome (0.1%) eye drops, administered once a day (s.i.d.), twice a day (b.i.d.), and three times a day (t.i.d.), also reduced CNV formation in a frequency-dependent manner. Furthermore, diclofenac-loaded liposome (0.03% and 0.1%) eye drops administered t.i.d. reduced CNV formation in a dose-dependent manner, significantly so at 0.1%. In the common marmoset CNV model, late hyperfluorescence and leakage by fluorescein angiograms was observed within or beyond the lesion borders at 17 days after laser irradiation, and diclofenac-loaded liposome eye drops (0.1% t.i.d.) tended to attenuate the late hyperfluorescence and leakage. Diclofenac-loaded liposomes had significantly reduced CNV formation in the RPE- choroidal flatmounts at 21 days after laser irradiation. In conclusion, diclofenac-loaded liposome eye drops enhance penetration to the RPE-choroid, and reduce the CNV formation. These results suggest that a drug-loaded liposome is a useful tool for drug delivery into the posterior segment of the eye.

Edaravone is a free radical scavenger that protects against laser-induced choroidal neovascularization in mice and common marmosets.

Choroidal neovascularization (CNV) is a main characteristic in exudative type of age-related macular degeneration (AMD). Our study aimed to evaluate the effects of edaravone, a free radical scavenger on laser-induced CNV. CNV was induced by laser photocoagulation to the subretinal choroidal area of mice and common marmosets. Edaravone was administered either intraperitoneally twice a day for 2 weeks or intravenously just once after laser photocoagulation. The effects of edaravone on laser-induced CNV were evaluated by fundus fluorescein angiography, CNV area measurements, and the expression of 4-hydroxy-2-nonenal (4-HNE) modified proteins, a marker of oxidative stress. Furthermore, the effects of edaravone on the production of H2O2-induced reactive oxygen species (ROS) and vascular endothelial growth factor (VEGF)-induced cell proliferation were evaluated using human retinal pigment epithelium cells (ARPE-19) and human retinal microvascular endothelial cells, respectively. CNV areas in the edaravone-treated group were significantly smaller in mice and common marmosets. The expression of 4-HNE modified proteins was upregulated 3 h after laser photocoagulation, and intravenously administered edaravone decreased it. In in vitro studies, edaravone inhibited H2O2-induced ROS production and VEGF-induced cell proliferation. These findings suggest that edaravone may protect against laser-induced CNV by inhibiting oxidative stress and endothelial cell proliferation.