Ocular findings in patients with acquired ATTRv amyloidosis following domino liver transplantation.

PURPOSE: To investigate the presence of amyloidosis-related ocular findings in patients who received domino liver transplantation from ATTRv amyloidosis donors. METHODS: We reviewed the ocular findings in patients who had previously undergone domino liver transplantation and received ophthalmologic examinations between January 2009 and March 2023. The presence of amyloidosis-related ocular findings was retrospectively assessed by two ophthalmologists. RESULTS: During the study period, a total of 7 patients with 14 eyes were examined. All patients were considered as acquired ATTRv amyloidosis. The mean age at the final visit was 64.6±8.4 years (52-75 years), and the mean time since domino liver transplantation was 167.6±76.2 months (69-257 months). The two evaluators' assessments for amyloidosis-related ocular findings were completely identical. No amyloid fibril deposition was observed in the pupil, lens, or vitreous. Five patients (10 eyes) had a Schirmer test result of 5mm or less than 5 mm, and four patients with a total of 8 eyes underwent fluorescein angiography and indocyanine green angiography, and no evidence of retinal amyloid angiopathy was found on fluorescein angiography. However, three patients with 6 eyes showed choroidal amyloid angiopathy on indocyanine green angiography. CONCLUSION: While cases of choroidal amyloid angiopathy were observed, serious amyloidosis-related ocular complications such as vitreous opacity or secondary glaucoma did not occur even in the long term after domino liver transplantation.

Long-term surgical results of trabeculectomy for secondary glaucoma in Val30Met hereditary transthyretin amyloidosis.

This study reports the long-term results of trabeculectomy (LEC) for secondary glaucoma in hereditary transthyretin (ATTRv) amyloidosis patients and its correlation with prior vitrectomy. A retrospective case series was conducted involving 31 consecutive eyes of 20 ATTRv amyloidosis patients who underwent LEC between 2007 and 2020. The mean follow-up period was 73.2 ± 37.0 months (range: 20-181 months). Postoperative intraocular pressures (IOPs) were evaluated based on the following criteria: (a) IOP between 6 and 21 mmHg without additional glaucoma surgeries, except for laser suture lysis, (b) IOP between 6 and 15 mmHg without additional glaucoma surgeries, except for laser suture lysis, and (c) IOP between 6 and 21 mmHg without additional glaucoma surgeries, except for needling and laser suture lysis. Kaplan-Meier analysis revealed survival rates after LEC of 0.52 at 36 months, 0.42 at 60 months, and 0.25 at 84 months under criterion (a); 0.49 at 36 months, 0.27 at 60 months, and 0.11 at 84 months under criterion (b); and 0.76 at 36 months, 0.71 at 60 months, and 0.65 at 84 months under criterion (c). Eyes with a history of small gauge transconjunctival vitrectomy (SGTV) exhibited a tendency towards lower survival rates, although no statistically significant difference was observed (log-rank test; p = 0.193 under criterion (a) and p = 0.0553 under criterion (b)). Our findings suggest that LEC and additional needling procedures can provide some control over IOP; however, the overall postoperative outcomes of LEC for ATTRv amyloidosis remain unsatisfactory, even in the era of SGTV with reduced conjunctival scarring.

Role of Adrenomedullin 2/Intermedin in the Pathogenesis of Neovascular Age-Related Macular Degeneration.

Adrenomedullin 2 (AM2; also known as intermedin) is a member of the adrenomedullin (AM) peptide family. Similarly to AM, AM2 partakes in a variety of physiological activities. AM2 has been reported to exert protective effects on various organ disorders; however, its significance in the eye is unknown. We investigated the role of AM2 in ocular diseases. The receptor system of AM2 was expressed more abundantly in the choroid than in the retina. In an oxygen-induced retinopathy model, physiological and pathologic retinal angiogenesis did not differ between AM2-knockout (AM2-/-) and wild-type mice. In contrast, in laser-induced choroidal neovascularization, a model of neovascular age-related macular degeneration, AM2-/- mice had enlarged and leakier choroidal neovascularization lesions, with exacerbated subretinal fibrosis and macrophage infiltration. Contrary to this, exogenous administration of AM2 ameliorated the laser-induced choroidal neovascularization-associated pathology and suppressed gene expression associated with inflammation, fibrosis, and oxidative stress, including that of VEGF-A, VEGFR-2, CD68, CTGF, and p22-phox. The stimulation of human adult retinal pigment epithelial (ARPE) cell line 19 cells with TGF-ß2 and TNF-α induced epithelial-to-mesenchymal transition (EMT), whereas AM2 expression was also elevated. The induction of EMT was suppressed when the ARPE-19 cells were pretreated with AM2. A transcriptome analysis identified 15 genes, including mesenchyme homeobox 2 (Meox2), whose expression was significantly altered in the AM2-treated group compared with that in the control group. The expression of Meox2, a transcription factor that inhibits inflammation and fibrosis, was enhanced by AM2 treatment and attenuated by endogenous AM2 knockout in the early phase after laser irradiation. The AM2 treatment of endothelial cells inhibited endothelial to mesenchymal transition and NF-κB activation; however, this effect tended to be canceled following Meox2 gene knockdown. These results indicate that AM2 suppresses the neovascular age-related macular degeneration-related pathologies partially via the upregulation of Meox2. Thus, AM2 may be a promising therapeutic target for ocular vascular diseases.

Microhook ab interno trabeculotomy for secondary glaucoma in patients with hereditary transthyretin amyloidosis.

PURPOSE: To report surgical outcomes of a Microhook ab interno trabeculotomy (µLOT) procedure for glaucoma secondary to hereditary transthyretin amyloidosis (ATTRv). STUDY DESIGN: Retrospective case series. METHODS: Medical records of patients with glaucoma secondary to ATTRv with transthyretin Val30Met variant, who underwent µLOT, were retrospectively reviewed. Surgical success was categorized according to the postoperative intraocular pressures (IOPs, mmHg) as follows: (a) 6 ≤ IOP ≤ 21; (b) 6 ≤ IOP ≤ 18; and (c) 6 ≤ IOP ≤ 15, without light perception loss or additional glaucoma surgery. Secondary outcomes were glaucoma medication scores and postoperative complications. RESULTS: This study included 18 eyes (13 patients, 6 men). The mean follow-up period was 25.2±9.8 months (7-38 months). Kaplan-Meier analysis indicated success rates of (a) 1.00 at 6, 1.00 at 12, and 0.43 at 24 months; (b), 1.00 at 6, 0.93 at 12, and 0.43 at 24 months; (c) 0.94 at 6, 0.75 at 12, and 0.27 at 24 months after operation. Postoperative IOPs were significantly reduced from the baseline of 25.2±5.8 mmHg to 11.5±2.7 at 3, 12.3±4.1 at 6, and 13.8±3.9 at 12 months (Dunnett's test). Medication scores were also improved at 3 and 6 months but without a significant reduction at 12 months. There were no severe complications requiring surgical intervention except for additional glaucoma surgery. CONCLUSION: µLOT for secondary glaucoma in ATTRv is safe and effective 1 year after surgery, but the effects diminish after 2 years.

Application of optical coherence tomography angiography to assess systemic severity in patients with hereditary transthyretin amyloidosis.

Hereditary transthyretin amyloidosis is an autosomal dominant form of amyloidosis caused by an abnormality in transthyretin, with various ocular manifestations. Among these, ocular amyloid angiopathy has attracted attention because of its direct link to visual impairment and its correlation with systemic severity. We hypothesized that optical coherence tomography angiographic parameters would be useful biomarkers of amyloidosis systemic severity and investigated their correlation with the systemic severity score. The primary outcome was the correlation between the systemic severity score and choriocapillaris flow deficit percentage. Secondary outcomes were the correlations between the systemic severity score and retinal optical coherence tomography angiographic parameters, including foveal avascular zone size and circularity and superficial/deep/total retinal perfusion and vessel densities. The choroidal and retinal vasculature was quantified in 36 eyes from 36 patients (age, 51.8±12.1 years; disease duration, 13.4±6.2 years). Ten eyes had a history of vitrectomy for vitreous opacity. Choriocapillaris flow deficit percentage was not significantly correlated with the systemic severity score (Spearman's rank correlation: r = 2.96×10-2, p = 0.863). Similarly, foveal avascular zone size and circularity, and superficial/deep/total retinal perfusion and vessel densities were not significantly correlated with the systemic severity score. These results may indicate that optical coherence tomography angiographic parameters are not sufficient to predict amyloidosis severity.

CHOROIDAL AMYLOID DEPOSITION: A Multicenter Study of Amyloid Lesions Identified in Late Indocyanine Green Angiography.

PURPOSE: To characterize choroidal amyloid angiopathy (CAA) using late-phase indocyanine green angiography (ICGA). METHODS: This was a multicenter retrospective observational case series on patients with transthyretin (ATTR) and AL amyloidosis who underwent ICGA. The timing of hyperfluorescence and longitudinal changes were analyzed. RESULTS: Thirty-two patients (27 with ATTR and 5 with AL) with mean age of 58.9 ± 17.4 years were included. Hyperfluorescent spots in the very late phases of ICGA, corresponding to CAA, were observed in 49 of 55 eyes (89%). The median time to maximal staining was 672 (95% confidence interval, 644-752) seconds, which was significantly later than the initial staining (503 [95% confidence interval, 447-521], P < 0.0001; Wilcoxon signed rank test). In seven patients with ATTR amyloidosis who underwent follow-up of ICGA, the CAA was stable in two patients and improved in five patients during treatment. However, 3 patients (43%) had worsening vitreous opacities in both eyes, and 4 patients (57%) developed secondary open-angle glaucoma. CONCLUSION: Most patients with amyloidosis were found to have CAA on ICGA. Up to 12.5 minutes is required for maximal ICG staining. Choroidal amyloid angiopathy improved in most patients with systemic treatment and may serve as a marker of systemic disease status.

OCULAR ANGIOGRAPHIC FEATURES IN JAPANESE PATIENTS WITH VAL30MET HEREDITARY TRANSTHYRETIN AMYLOIDOSIS.

PURPOSE: To investigate ocular angiographic features of hereditary transthyretin amyloidosis with transthyretin Val30Met mutation (hATTR-V30M) in Japanese patients. METHODS: We retrospectively reviewed 102 eyes of 51 patients with hATTR-V30M who underwent fluorescein angiograms and indocyanine green angiograms between 2012 and 2018. Systemic severity score, fluorescein angiograms, indocyanine green angiograms, and ocular amyloidosis presentations at the final angiograms and subsequent neovascular events were evaluated. Primary outcomes were the frequency of choroidal amyloid angiopathy and retinal amyloid angiopathy (RAA). Secondary outcomes were their correlations to the systemic severity score. RESULTS: Six eyes could not be evaluated by fluorescein angiogram because of vitreous opacity. Of 96 eyes evaluated, RAA was detected in 36 (37.5%). Neovascularization was not detected. Indocyanine green angiogram indicated choroidal amyloid angiopathy in 46/51 patients (90.2%), with distinct patterns-diffuse (n = 6), focal (n = 14), and punctiform (n = 26)-based on late-phase hypercyanescence. Retinal amyloid angiopathy and choroidal amyloid angiopathy grades were associated with systemic severity (ρ = 0.57 and 0.50, respectively; both P < 0.05). At 35.4 ± 28.4 (0-96) months, iris-rubeosis was observed in one eye and vitreous hemorrhage in two. CONCLUSION: Retinal amyloid angiopathy was less common and choroidal amyloid angiopathy was frequent, and their severity correlated with the systemic severity score. The frequencies of RAA and subsequent neovascular events in this study may suggest regional differences in the ocular angiographic features of hATTR-V30M.

Adrenomedullin Ameliorates Pulmonary Fibrosis by Regulating TGF-ß-Smads Signaling and Myofibroblast Differentiation.

Pulmonary fibrosis is an irreversible, potentially fatal disease. Adrenomedullin (AM) is a multifunctional peptide whose activity is regulated by receptor activity-modifying protein 2 (RAMP2). In the present study, we used the bleomycin (BLM)-induced mouse pulmonary fibrosis model to investigate the pathophysiological significance of the AM-RAMP2 system in the lung. In heterozygous AM knockout mice (AM+/-), hydroxyproline content and Ashcroft scores reflecting the fibrosis severity were significantly higher than in wild-type mice (WT). During the acute phase after BLM administration, FACS analysis showed significant increases in eosinophil, monocyte, and neutrophil infiltration into the lungs of AM+/-. During the chronic phase, fibrosis-related molecules were upregulated in AM+/-. Notably, nearly identical changes were observed in RAMP2+/-. AM administration reduced fibrosis severity. In the lungs of BLM-administered AM+/-, the activation level of Smad3, a receptor-activated Smad, was higher than in WT. In addition, Smad7, an antagonistic Smad, was downregulated and microRNA-21, which targets Smad7, was upregulated compared to WT. Isolated AM+/- lung fibroblasts showed less proliferation and migration capacity than WT fibroblasts. Stimulation with TGF-ß increased the numbers of α-SMA-positive myofibroblasts, which were more prominent among AM+/- cells. TGF-ß-stimulated AM+/- myofibroblasts were larger and exhibited greater contractility and extracellular matrix production than WT cells. These cells were α-SMA (+), F-actin (+), and Ki-67(-) and appeared to be nonproliferating myofibroblasts (non-p-MyoFbs), which contribute to the severity of fibrosis. Our findings suggest that in addition to suppressing inflammation, the AM-RAMP2 system ameliorates pulmonary fibrosis by suppressing TGF-ß-Smad3 signaling, microRNA-21 activity and differentiation into non-p-MyoFbs.

Micropulse laser trabeculoplasty under maximal tolerable glaucoma eyedrops: treatment effectiveness and impact of surgical expertise.

AIM: To evaluate the effectiveness of micropulse laser trabeculoplasty (MLT) for eyes with open angle glaucoma (OAG) under maximal tolerable glaucoma eyedrops and to assess the effect of expertise performing MLT on its clinical effectiveness. METHODS: Medical records of 42 consecutive eyes of 34 patients diagnosed with OAG who underwent MLT were retrospectively reviewed. The effectiveness was determined using the Kaplan-Meier survival analysis. Failure was defined as an intraocular pressure (IOP) reduction of <20% from baseline, an IOP >21 mm Hg during two consecutive follow-up visits, or surgical intervention for OAG. To determine the impact of MLT surgical expertise on clinical effectiveness, the eyes were divided into two groups according to whether the procedure was conducted by an experienced specialist (defined as a glaucoma specialist who had conducted at least ten MLT procedures) or a less experienced glaucoma specialist. The difference in expertise was determined using a log-rank test. RESULTS: MLT was conducted by three glaucoma specialists. The overall survival rates were 0.76, 0.48, and 0.44 at 1, 3, and 6mo, respectively. The survival rates for MLT performed by a less experienced glaucoma specialist were 0.62, 0.31, and 0.25 (n=21 eyes) at 1, 3, and 6mo, respectively, whereas the survival rates for MLT performed by an experienced glaucoma specialist were 0.90, 0.64, and 0.64 (n=21 eyes) at 1, 3, and 6mo, respectively. The log-rank test showed a significant difference in the survival curves of the two groups (P=0.0061). CONCLUSION: The 6-month effectiveness of MLT for controlling IOP is relatively limited in eyes with OAG using maximal tolerable glaucoma eyedrops. However, its effectiveness may be improved if performed by a glaucoma specialist with sufficient MLT experience.

Adrenomedullin-RAMP2 and -RAMP3 Systems Regulate Cardiac Homeostasis during Cardiovascular Stress.

Adrenomedullin (AM) is a peptide hormone with multiple physiological functions, which are regulated by its receptor activity-modifying proteins, RAMP2 and RAMP3. We previously reported that AM or RAMP2 knockout (KO) (AM-/-, RAMP2-/-) is embryonically lethal in mice, whereas RAMP3-/- mice are apparently normal. AM, RAMP2, and RAMP3 are all highly expressed in the heart; however, their functions there are not fully understood. Here, we analyzed the pathophysiological functions of the AM-RAMP2 and AM-RAMP3 systems in hearts subjected to cardiovascular stress. Cardiomyocyte-specific RAMP2-/- (C-RAMP2-/-) and RAMP3-/- showed no apparent heart failure at base line. After 1 week of transverse aortic constriction (TAC), however, C-RAMP2-/- exhibited significant cardiac hypertrophy, decreased ejection fraction, and increased fibrosis compared with wild-type mice. Both dP/dtmax and dP/dtmin were significantly reduced in C-RAMP2-/-, indicating reduced ventricular contractility and relaxation. Exposing C-RAMP2-/- cardiomyocytes to isoproterenol enhanced their hypertrophy and oxidative stress compared with wild-type cells. C-RAMP2-/- cardiomyocytes also contained fewer viable mitochondria and showed reduced mitochondrial membrane potential and respiratory capacity. RAMP3-/- also showed reduced systolic function and enhanced fibrosis after TAC, but those only became apparent after 4 weeks. A reduction in cardiac lymphatic vessels was the characteristic feature in RAMP3-/-. These observations indicate the AM-RAMP2 system is necessary for early adaptation to cardiovascular stress through regulation of cardiac mitochondria. AM-RAMP3 is necessary for later adaptation through regulation of lymphatic vessels. The AM-RAMP2 and AM-RAMP3 systems thus play separate critical roles in the maintenance of cardiovascular homeostasis against cardiovascular stress.

Deposits on Retinal Surface Seen on OCT in Ocular Amyloidosis.

PURPOSE: To investigate the tomographic features in patients with hereditary amyloidosis transthyretin (hATTR). DESIGN: Retrospective case series and analysis of B-scan OCT images. PARTICIPANTS: A total of 120 patients (240 eyes) diagnosed with hATTR. METHODS: We performed a retrospective review of the treatment history and retrospective analysis of the OCT images of patients with hATTR. The parameters analyzed were the age at which the last OCT was performed, presence of ocular amyloidosis, history of pars plana vitrectomy (PPV), systemic treatment, and genetic mutations. Two independent evaluators evaluated the OCT images for characteristic needle-shaped pattern deposits on the retinal surface, and a third evaluator resolved any differences in their evaluations. MAIN OUTCOME MEASURES: The frequency of characteristic needle-shaped deposits on the retinal surface seen on OCT. RESULTS: The mean age at the time of the last OCT was 56.5 ± 14.9 years. Ninety-nine patients had gene encoding transthyretin (TTR) with the Val30Met mutation, and 21 patients had other mutations. Of 240 eyes, 128 had signs of ocular amyloidosis. Fifty of 73 eyes (68.5%) with a history of PPV for vitreous opacities exhibited characteristic deposits on OCT. Four of 31 eyes with vitreous opacity but without a history of PPV showed deposits on the retinal surface. No eyes without a history of vitreous opacities revealed the characteristic needle-shaped deposits. CONCLUSIONS: Characteristic needle-shaped deposits on the retinal surface seen on OCT are significant because they are seen in most of the vitrectomized eyes presenting with ocular amyloidosis.

Adrenomedullin-Receptor Activity-Modifying Protein 2 System Ameliorates Subretinal Fibrosis by Suppressing Epithelial-Mesenchymal Transition in Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is a leading cause of visual impairment. Anti-vascular endothelial growth factor drugs used to treat AMD carry the risk of inducing subretinal fibrosis. We investigated the use of adrenomedullin (AM), a vasoactive peptide, and its receptor activity-modifying protein 2, RAMP2, which regulate vascular homeostasis and suppress fibrosis. The therapeutic potential of the AM-RAMP2 system was evaluated after laser-induced choroidal neovascularization (LI-CNV), a mouse model of AMD. Neovascular formation, subretinal fibrosis, and macrophage invasion were all enhanced in both AM and RAMP2 knockout mice compared with those in wild-type mice. These pathologic changes were suppressed by intravitreal injection of AM. Comprehensive gene expression analysis of the choroid after LI-CNV with or without AM administration revealed that fibrosis-related molecules, including Tgfb, Cxcr4, Ccn2, and Thbs1, were all down-regulated by AM. In retinal pigment epithelial cells, co-administration of transforming growth factor-ß and tumor necrosis factor-α induced epithelial-mesenchymal transition, which was also prevented by AM. Finally, transforming growth factor-ß and C-X-C chemokine receptor type 4 (CXCR4) inhibitors eliminated the difference in subretinal fibrosis between RAMP2 knockout and wild-type mice. These findings suggest the AM-RAMP2 system suppresses subretinal fibrosis in LI-CNV by suppressing epithelial-mesenchymal transition.

Baerveldt glaucoma drainage implant surgery for secondary glaucoma in patients with transthyretin-related familial amyloid polyneuropathy.

PURPOSE: To investigate outcomes associated with Baerveldt glaucoma drainage implant (BGI) surgery for refractory glaucoma secondary to transthyretin (TTR)-related familial amyloid polyneuropathy (FAP) with TTR Val30Met mutation. STUDY DESIGN: Retrospective case series. METHODS: Medical records of 5 eyes of 4 patients were reviewed. All patients had refractory glaucoma secondary to FAP with a history of unsuccessful intraocular pressure (IOP) control by trabeculectomy with mitomycin C, underwent BGI surgery, and were followed up for at least 1 year. The primary outcome was mean postoperative IOP, and secondary outcomes included the number of ocular hypotensive medications and postoperative complications. RESULTS: The mean postoperative follow-up period was 52.4 months. The mean preoperative IOP of 37.0 mmHg was reduced to 13.4 mmHg immediately postoperatively, and respective subsequent means were 15.8, 13.0, 14.4, and 16.8 mmHg at 1, 3, 6, 12, and 24 months (P < 0.05). The preoperative mean number of ocular hypotensive medications of 5.4 was reduced to respective means of 2.2, 1.6, 2.8, 2.8, and 2.8 at 1, 3, 6, 12, and 24 months. One eye suffered from IOP elevation and underwent cyclophotocoagulation at 26 months. Another was dropped from further analyses because of deterioration in the patient's general condition due to FAP progression. The remaining 3 eyes exhibited adequate IOP control (13, 13, 13 mmHg) at the final visit. CONCLUSION: BGI surgery may be the current optimal treatment for patients with refractory glaucoma secondary to TTR-FAP with regard to achieving long-term IOP reduction.

Investigation of the therapeutic mechanism of subthreshold micropulse laser irradiation in retina.

PURPOSE: Subthreshold micropulse laser irradiation has been used for the treatment of retinal edema; however, there are few reports about the mechanism of its therapeutic effect. In this study, we compared threshold short pulse and subthreshold micropulse laser irradiation in mice and investigated their mechanism. METHODS: Nine to 12-week-old male C57BL/6J mice were used in this study. After general anesthesia, threshold short pulse or subthreshold micropulse laser irradiation was performed on the right eye using IQ577. Enucleation was performed 24 h after the laser irradiation, and histological and gene expression analyses were carried out. RESULTS: Coagulation spots and atrophy of the retinal pigment epithelium were observed after threshold short pulse laser irradiation but not after subthreshold micropulse laser irradiation. Twenty-four hours after laser, aquaporin (AQP) 1, 2, 7, and 11 levels were significantly elevated by 1.7- to 3-fold in the threshold short pulse laser group compared with non-treated control group. AQP 3 was increased significantly and prominently by 100-fold. VEGF-A and VEGFR2 were upregulated 1.5- and 2.3-fold, respectively. In the subthreshold micropulse laser group, AQP 3 was increased by 6-fold compared with the non-treated control group. Angiopoietin-1 and the adrenomedullin (AM) receptor CLR were decreased by 0.6-fold and 0.5-fold, respectively. CONCLUSION: Threshold short pulse laser irradiation caused retinal damage and prominent changes in the expression of various genes. Contrarily, subthreshold micropulse laser irradiation did not induce retinal damage; it upregulated AQP 3, which might have improved retinal edema by drainage of subretinal fluid.

Small gauge vitrectomy for vitreous amyloidosis and subsequent management of secondary glaucoma in patients with hereditary transthyretin amyloidosis.

We conducted a retrospective observational study including 31 eyes of 20 patients in order to investigate the efficacy of 25-gauge vitrectomy for vitreous opacity with minimal conjunctival invasion and subsequent management of intraocular pressure (IOP) secondary to hereditary transthyretin amyloidosis. We followed up these patients for an average of 44.7 ± 32.6 months. The primary outcome was best corrected visual acuity (BCVA) at 1 month after surgery and at the final follow-up visit, with management of subsequent IOP elevation. Secondary outcomes included the post-vitrectomy IOP survival rate, to determine the frequency of IOP elevation requiring glaucoma surgery. Mean age at vitrectomy was 55.4 ± 9.1 years. Logarithm of the Minimum Angle of Resolution (LogMAR) BCVA showed immediate improvement from 0.73 ± 0.62 to 0.00 ± 0.22 at 1 month (p = 4.1 × 10-7), an improvement that was maintained up to the final follow-up visit, when IOP was maintained at 13.1 ± 5.2 mmHg. The survival rate of post-vitrectomy IOP control was 0.51, 0.38, and 0.23 at 12, 24, and 60 months, respectively. A poor post-vitrectomy IOP survival rate suggests that removing vitreous amyloid via 25-gauge vitrectomy is not sufficient to guarantee good visual function; subsequent careful follow-up and proper glaucoma management is also required in order to achieve this goal.

Deficiency of the adrenomedullin-RAMP3 system suppresses metastasis through the modification of cancer-associated fibroblasts.

Tumor metastasis is a primary source of morbidity and mortality in cancer. Adrenomedullin (AM) is a multifunctional peptide regulated by receptor activity-modifying proteins (RAMPs). We previously reported that the AM-RAMP2 system is involved in tumor angiogenesis, but the function of the AM-RAMP3 system remains largely unknown. Here, we investigated the actions of the AM-RAMP2 and 3 systems in the tumor microenvironment and their impact on metastasis. PAN02 pancreatic cancer cells were injected into the spleens of mice, leading to spontaneous liver metastasis. Tumor metastasis was enhanced in vascular endothelial cell-specific RAMP2 knockout mice (DI-E-RAMP2-/-). By contrast, metastasis was suppressed in RAMP3-/- mice, where the number of podoplanin (PDPN)-positive cancer-associated fibroblasts (CAFs) was reduced in the periphery of tumors at metastatic sites. Because PDPN-positive CAFs are a hallmark of tumor malignancy, we assessed the regulation of PDPN and found that Src/Cas/PDPN signaling is mediated by RAMP3. In fact, RAMP3 deficiency CAFs suppressed migration, proliferation, and metastasis in co-cultures with tumor cells in vitro and in vivo. Moreover, the activation of RAMP2 in RAMP3-/- mice suppressed both tumor growth and metastasis. Based on these results, we suggest that the upregulation of PDPN in DI-E-RAMP2-/- mice increases malignancy, while the downregulation of PDPN in RAMP3-/- mice reduces it. Selective activation of RAMP2 and inhibition of RAMP3 would therefore be expected to suppress tumor metastasis. This study provides the first evidence that understanding and targeting to AM-RAMP systems could contribute to the development of novel therapeutics against metastasis.