Outcomes of open versus robotic partial nephrectomy: a 20-year single institution experience.

Robotic assisted partial nephrectomy (RPN) has emerged in urologic practice for the management of appropriately sized renal masses. We provide a 20-year comparison of the outcomes of open partial nephrectomy (OPN) versus RPN for renal cell carcinoma (RCC) at our institution. An IRB-approved retrospective review was conducted of RCC patients at a single institution from 2000 to 2022 who underwent RPN or OPN. In addition to demographics, procedural details including ischemia and operative time were collected. Oncologic outcomes were evaluated through Kaplan-Meier statistical analysis to determine recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) analysis. 849 patients underwent RPN while 385 underwent OPN. 61% were male with average age of 58.8 ± 12.8 years. Operative time was shorter in the open group (184 vs 200 min, p = 0.002), as was ischemia time (16 vs 19 min, p = 0.047). However, after 2012, RPN became more common than OPN with improving ischemia time. RPN patients had significantly improved RFS (HR 0.45, p = 0.0004) and OS (HR 0.51, p = 0.0016) when controlled for T-stage and margin status. More > pT1 masses were managed with OPN than RPN (11.2 vs 5.4%, p < 0.0001). At our institution, RPN had an increasing incidence with reduced ischemia time compared to OPN over the last 10 years. While higher stage renal masses were more often managed with OPN, selective use of RPN does offer improved oncologic outcomes. Further investigation is needed to evaluate optimization of the selection of RPN versus OPN in the nephron-sparing management of renal masses.

Intensive Glycemic Management Is Associated With Reduced Retinal Structure Abnormalities on Ocular Coherence Tomography in the DCCT/EDIC Study.

OBJECTIVE: To investigate quantitative and qualitative changes in retinal structure using optical coherence tomography (OCT) and their associations with systemic or other risk factors in individuals with type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS: In the Epidemiology of Diabetes Interventions and Complications (EDIC) study, OCT images were obtained during study years 25-28 (2019-2022) in 937 participants; 54% and 46% were from the original intensive (INT) and conventional (CONV) glycemic management treatment groups, respectively. RESULTS: Average age for participants was 61 years old, diabetes duration 39 years, and HbA1c 7.6%. Participants originally in the CONV group were more likely to have disorganization of retinal inner layers (DRIL) (CONV 27.3% vs. INT 18.7%; P = 0.0003), intraretinal fluid (CONV 24.4% vs. INT 19.2%; P = 0.0222), and intraretinal cysts (CONV 20.8% vs. INT 16.6%; P = 0.0471). In multivariable models, sex, age, smoking, mean updated systolic blood pressure, and history of "clinically significant" macular edema (CSME) and of anti-VEGF treatment were independently associated with changes in central subfield thickness, while HbA1c, BMI, and history of CSME and of ocular surgery were associated with DRIL. Visual acuity (VA) decline was associated with significant thinning of all retinal subfields except for the central and inner nasal subfields. CONCLUSIONS: Early intensive glycemic management in T1D is associated with a decreased risk of DRIL. This important morphological abnormality was associated with a history of macular edema, a history of ocular surgery, and worse VA. This study reveals benefits of intensive glycemic management on the retina beyond features detected by fundus photographs and ophthalmoscopy.

Dual targeting ovarian cancer by Muc16 CAR T cells secreting a bispecific T cell engager antibody for an intracellular tumor antigen WT1.

Epithelial ovarian cancer is the most lethal of gynecological cancers. The therapeutic efficacy of chimeric antigen receptor (CAR) T cell directed against single antigens is limited by the heterogeneous target antigen expression in epithelial ovarian tumors. To overcome this limitation, we describe an engineered cell with both dual targeting and orthogonal cytotoxic modalities directed against two tumor antigens that are highly expressed on ovarian cancer cells: cell surface Muc16 and intracellular WT1. Muc16-specific CAR T cells (4H11) were engineered to secrete a bispecific T cell engager (BiTE) constructed from a TCR mimic antibody (ESK1) reactive with the WT1-derived epitope RMFPNAPYL (RMF) presented by HLA-A2 molecules. The secreted ESK1 BiTE recruited and redirected other T cells to WT1 on the tumor cells. We show that ESK1 BiTE-secreting 4H11 CAR T cells exhibited enhanced anticancer activity against cancer cells with low Muc16 expression, compared to 4H11 CAR T cells alone, both in vitro and in mouse tumor models. Dual orthogonal cytotoxic modalities with different specificities targeting both surface and intracellular tumor-associated antigens present a promising strategy to overcome resistance to CAR T cell therapy in epithelial ovarian cancer and other cancers.

Development of a p-Hydroxybenzyl-Alcohol-Linked Glutamate Prodrug for Activation by Pseudomonas Carboxypeptidase G2.

Directed enzyme-prodrug therapies used for targeted drug delivery require prodrugs that are chemically stable and processed efficiently by the activating enzyme. We recently reported the development of AMS-6-Glu (2), a glutamate-masked version of the cytotoxic natural product 5'-O-sulfamoyladenosine (AMS, 1) that can be activated by Pseudomonas carboxypeptidase G2 (CPG2). Herein, we report the development of a second-generation prodrug, AMS-5'-PHOBA-Glu (5), that undergoes cleavage by CPG2 with >160-fold higher efficiency. Use of a p-hydroxybenzyl alcohol (PHOBA) self-immolative linker overcame unexpected chemical instability observed with a conventional p-aminobenzyl alchohol (PABA) linker.

Host Interactions with Engineered T-cell Micropharmacies.

Genetically engineered, cytotoxic, adoptively transferred T cells localize to antigen-positive cancer cells inside patients, but tumor heterogeneity and multiple immune escape mechanisms have prevented the eradication of most solid tumor types. More effective, multifunctional engineered T cells are in development to overcome the barriers to the treatment of solid tumors, but the interactions of these highly modified cells with the host are poorly understood. We previously engineered prodrug-activating enzymatic functions into chimeric antigen receptor (CAR) T cells, endowing them with a killing mechanism orthogonal to conventional T-cell cytotoxicity. These drug-delivering cells, termed Synthetic Enzyme-Armed KillER (SEAKER) cells, demonstrated efficacy in mouse lymphoma xenograft models. However, the interactions of an immunocompromised xenograft with such complex engineered T cells are distinct from those in an immunocompetent host, precluding an understanding of how these physiologic processes may affect the therapy. Herein, we expanded the repertoire of SEAKER cells to target solid-tumor melanomas in syngeneic mouse models using specific targeting with T-cell receptor (TCR)-engineered T cells. We demonstrate that SEAKER cells localized specifically to tumors, and activated bioactive prodrugs, despite host immune responses. We additionally show that TCR-engineered SEAKER cells were efficacious in immunocompetent hosts, demonstrating that the SEAKER platform is applicable to many adoptive cell therapies.

Host-cell Interactions of Engineered T cell Micropharmacies.

Genetically engineered, cytotoxic, adoptive T cells localize to antigen positive cancer cells inside patients, but tumor heterogeneity and multiple immune escape mechanisms have prevented the eradication of most solid tumor types. More effective, multifunctional engineered T cells are in development to overcome the barriers to the treatment of solid tumors, but the interactions of these highly modified cells with the host are poorly understood. We previously engineered prodrug-activating enzymatic functions into chimeric antigen receptor (CAR) T cells, endowing them with an orthogonal killing mechanism to conventional T-cell cytotoxicity. These drug-delivering cells, termed Synthetic Enzyme-Armed KillER (SEAKER) cells, demonstrated efficacy in mouse lymphoma xenograft models. However, the interactions of an immunocompromised xenograft with such complex engineered T cells are distinct from those in an immunocompetent host, precluding an understanding of how these physiologic processes may affect the therapy. Here, we also expand the repertoire of SEAKER cells to target solid-tumor melanomas in syngeneic mouse models using specific targeting with TCR-engineered T cells. We demonstrate that SEAKER cells localize specifically to tumors, and activate bioactive prodrugs, despite host immune responses. We additionally show that TCR-engineered SEAKER cells are efficacious in immunocompetent hosts, demonstrating that the SEAKER platform is applicable to many adoptive cell therapies.

Dual targeting ovarian cancer by Muc16 CAR-T cells secreting a bispecific T cell engager antibody for an intracellular tumor antigen WT1.

Epithelial ovarian cancer is the most lethal of gynecological cancers. The therapeutic efficacy of chimeric antigen receptor (CAR) T cell directed against single antigens is limited by the heterogeneous target antigen expression in epithelial ovarian tumors. To overcome this limitation, we describe an engineered cell with both dual targeting and orthogonal cytotoxic modalities directed against two tumor antigens that are highly expressed on ovarian cancer cells: cell surface Muc16 and intracellular WT1. Muc16-specific CAR-T cells (4H11) were engineered to secrete a bispecific T cell engager (BiTE) constructed from a TCR mimic antibody (ESK1) reactive with the WT1-derived epitope RMFPNAPYL (RMF) presented by HLA-A2 molecules. The secreted ESK1 BiTE recruited and redirected other T cells to WT1 on the tumor cells. We show that ESK1 BiTE-secreting 4H11 CAR-T cells exhibited enhanced anticancer activity against cancer cells with low Muc16 expression, compared to 4H11 CAR-T cells alone, both in vitro and in mouse tumor models. Dual orthogonal cytotoxic modalities with different specificities targeting both surface and intracellular tumor-associated antigens present a promising strategy to overcome resistance to CAR-T cell therapy in epithelial ovarian cancer and other cancers.

The effect of surgical weight loss on diabetes complications in individuals with class II/III obesity.

AIMS/HYPOTHESIS: The aim of this study was to determine the effect of bariatric surgery on diabetes complications in individuals with class II/III obesity (BMI > 35 kg/m2). METHODS: We performed a prospective cohort study of participants with obesity who underwent bariatric surgery. At baseline and 2 years following surgery, participants underwent metabolic phenotyping and diabetes complication assessments. The primary outcomes for peripheral neuropathy (PN) were a change in intra-epidermal nerve fibre density (IENFD, units = fibres/mm) at the distal leg and proximal thigh, the primary outcome for cardiovascular autonomic neuropathy (CAN) was a change in the expiration/inspiration (E/I) ratio, and the primary outcome for retinopathy was a change in the mean deviation on frequency doubling technology testing. RESULTS: Among 127 baseline participants, 79 completed in-person follow-up (age 46.0 ± 11.3 years [mean ± SD], 73.4% female). Participants lost a mean of 31.0 kg (SD 18.4), and all metabolic risk factors improved except for BP and total cholesterol. Following bariatric surgery, one of the primary PN outcomes improved (IENFD proximal thigh, +3.4 ± 7.8, p<0.01), and CAN (E/I ratio -0.01 ± 0.1, p=0.89) and retinopathy (deviation -0.2 ± 3.0, p=0.52) were stable. Linear regression revealed that a greater reduction in fasting glucose was associated with improvements in retinopathy (mean deviation point estimate -0.7, 95% CI -1.3, -0.1). CONCLUSIONS/INTERPRETATION: Bariatric surgery may be an effective approach to reverse PN in individuals with obesity. The observed stability of CAN and retinopathy may be an improvement compared with the natural progression of these conditions; however, controlled trials are needed.

Canine-Inspired Chemometric Analysis of Volatile Organic Compounds in Urine Headspace to Distinguish Prostate Cancer in Mice and Men.

Canines can identify prostate cancer with high accuracy by smelling volatile organic compounds (VOCs) in urine. Previous studies have identified VOC biomarkers for prostate cancer utilizing solid phase microextraction (SPME) gas chromatography-mass spectrometry (GC-MS) but have not assessed the ability of VOCs to distinguish aggressive cancers. Additionally, previous investigations have utilized murine models to identify biomarkers but have not determined if the results are translatable to humans. To address these challenges, urine was collected from mice with prostate cancer and men undergoing prostate cancer biopsy and VOCs were analyzed by SPME GC-MS. Prior to analysis, SPME fibers/arrows were compared, and the fibers had enhanced sensitivity toward VOCs with a low molecular weight. The analysis of mouse urine demonstrated that VOCs could distinguish tumor-bearing mice with 100% accuracy. Linear discriminant analysis of six VOCs in human urine distinguished prostate cancer with sensitivity = 75% and specificity = 69%. Another panel of seven VOCs could classify aggressive cancer with sensitivity = 78% and specificity = 85%. These results show that VOCs have moderate accuracy in detecting prostate cancer and a superior ability to stratify aggressive tumors. Furthermore, the overlap in the structure of VOCs identified in humans and mice shows the merit of murine models for identifying biomarker candidates.

Potentiating antibody-dependent killing of cancers with CAR T cells secreting CD47-SIRPα checkpoint blocker.

Chimeric antigen receptor (CAR) T-cell therapy has shown success in the treatment of hematopoietic malignancies; however, relapse remains a significant issue. To overcome this, we engineered "Orexi" CAR T cells to locally secrete a high-affinity CD47 blocker, CV1, at the tumor and treated tumors in combination with an orthogonally targeted monoclonal antibody. Traditional CAR T cells plus the antibody had an additive effect in xenograft models, and this effect was potentiated by CAR T-cell local CV1 secretion. Furthermore, OrexiCAR-secreted CV1 reversed the immunosuppression of myelomonocytoid cells both in vitro and within the tumor microenvironment. Local secretion of the CD47 inhibitor bypasses the CD47 sink found on all cells in the body and may prevent systemic toxicities. This combination of CAR T-cell therapy, local CD47 blockade, and orthogonal antibody may be a combinatorial strategy to overcome the limitations of each monotherapy.

American Association of Clinical Endocrinology Clinical Practice Guideline: Developing a Diabetes Mellitus Comprehensive Care Plan-2022 Update.

OBJECTIVE: The objective of this clinical practice guideline is to provide updated and new evidence-based recommendations for the comprehensive care of persons with diabetes mellitus to clinicians, diabetes-care teams, other health care professionals and stakeholders, and individuals with diabetes and their caregivers. METHODS: The American Association of Clinical Endocrinology selected a task force of medical experts and staff who updated and assessed clinical questions and recommendations from the prior 2015 version of this guideline and conducted literature searches for relevant scientific papers published from January 1, 2015, through May 15, 2022. Selected studies from results of literature searches composed the evidence base to update 2015 recommendations as well as to develop new recommendations based on review of clinical evidence, current practice, expertise, and consensus, according to established American Association of Clinical Endocrinology protocol for guideline development. RESULTS: This guideline includes 170 updated and new evidence-based clinical practice recommendations for the comprehensive care of persons with diabetes. Recommendations are divided into four sections: (1) screening, diagnosis, glycemic targets, and glycemic monitoring; (2) comorbidities and complications, including obesity and management with lifestyle, nutrition, and bariatric surgery, hypertension, dyslipidemia, retinopathy, neuropathy, diabetic kidney disease, and cardiovascular disease; (3) management of prediabetes, type 2 diabetes with antihyperglycemic pharmacotherapy and glycemic targets, type 1 diabetes with insulin therapy, hypoglycemia, hospitalized persons, and women with diabetes in pregnancy; (4) education and new topics regarding diabetes and infertility, nutritional supplements, secondary diabetes, social determinants of health, and virtual care, as well as updated recommendations on cancer risk, nonpharmacologic components of pediatric care plans, depression, education and team approach, occupational risk, role of sleep medicine, and vaccinations in persons with diabetes. CONCLUSIONS: This updated clinical practice guideline provides evidence-based recommendations to assist with person-centered, team-based clinical decision-making to improve the care of persons with diabetes mellitus.

Early and Midterm Complications of the Continent Catheterizable Indiana Pouch Urinary Diversion: A 7-year Experience.

OBJECTIVES: To describe the most recent 7 year experience with 137 Indiana pouch patients at a single institution and provide data on complications with this type of urinary diversion during the first postoperative year. METHODS: We queried our bladder cancer database to identify all patients who underwent cystectomy with continent catheterizable urinary reservoir between 2012 and 2018. Pre-, intra-, and postoperative data were collected. Complications were stratified into early (within 90 days) and midterm (90-365 days). The primary outcomes were postoperative complications, and overall and cancer-specific mortality. RESULTS: A total of 137 patients underwent open cystectomy with Indiana pouch creation. Of these, 93% were radical cystectomies. On average, the operation took 422 minutes. There were 53 (39%) patients who experienced any type of complication during the first postoperative year (Clavien II-V). Twenty-five patients (18.2%) readmitted in the early postoperative period vs 18 (13.1%) patients midterm. There were 10 (7.3%) patients that required early reoperation and 11 (8%) in the midterm period. The overall mortality rate was 1.5% early and 3.7% midterm, with the majority of the mortality rate attributed to cancer progression (85.7%). CONCLUSION: Patients undergoing continent catheterizable reservoir urinary diversion appear to have comparable complication rates to other urinary diversions published in the literature. At high-volume urologic institutions, Indiana Pouch creation is a suitable option for select patients desiring a continent diversion.

mTORC1 regulates high levels of protein synthesis in retinal ganglion cells of adult mice.

Mechanistic target of rapamycin (mTOR) and mTOR complex 1 (mTORC1), linchpins of the nutrient sensing and protein synthesis pathways, are present at relatively high levels in the ganglion cell layer (GCL) and retinal ganglion cells (RGCs) of rodent and human retinas. However, the role of mTORCs in the control of protein synthesis in RGC is unknown. Here, we applied the SUrface SEnsing of Translation (SUnSET) method of nascent protein labeling to localize and quantify protein synthesis in the retinas of adult mice. We also used intravitreal injection of an adeno-associated virus 2 vector encoding Cre recombinase in the eyes of mtor- or rptor-floxed mice to conditionally knockout either both mTORCs or only mTORC1, respectively, in cells within the GCL. A novel vector encoding an inactive Cre mutant (CreΔC) served as control. We found that retinal protein synthesis was highest in the GCL, particularly in RGC. Negation of both complexes or only mTORC1 significantly reduced protein synthesis in RGC. In addition, loss of mTORC1 function caused a significant reduction in the pan-RGC marker, RNA-binding protein with multiple splicing, with little decrease of the total number of cells in the RGC layer, even at 25 weeks after adeno-associated virus-Cre injection. These findings reveal that mTORC1 signaling is necessary for maintaining the high rate of protein synthesis in RGCs of adult rodents, but it may not be essential to maintain RGC viability. These findings may also be relevant to understanding the pathophysiology of RGC disorders, including glaucoma, diabetic retinopathy, and optic neuropathies.

A TCR mimic CAR T cell specific for NDC80 is broadly reactive with solid tumors and hematologic malignancies.

Target identification for chimeric antigen receptor (CAR) T-cell therapies remains challenging due to the limited repertoire of tumor-specific surface proteins. Intracellular proteins presented in the context of cell surface HLA provide a wide pool of potential antigens targetable through T-cell receptor mimic antibodies. Mass spectrometry (MS) of HLA ligands from 8 hematologic and nonhematologic cancer cell lines identified a shared, non-immunogenic, HLA-A*02-restricted ligand (ALNEQIARL) derived from the kinetochore-associated NDC80 gene. CAR T cells directed against the ALNEQIARL:HLA-A*02 complex exhibited high sensitivity and specificity for recognition and killing of multiple cancer types, especially those of hematologic origin, and were efficacious in mouse models against a human leukemia and a solid tumor. In contrast, no toxicities toward resting or activated healthy leukocytes as well as hematopoietic stem cells were observed. This shows how MS can inform the design of broadly reactive therapeutic T-cell receptor mimic CAR T-cell therapies that can target multiple cancer types currently not druggable by small molecules, conventional CAR T cells, T cells, or antibodies.

It is time for a moonshot to find "Cures" for diabetic retinal disease.

Diabetic retinal disease (DRD), the most common complication of diabetes and a leading cause of blindness in working age individuals, is now understood to be a form of sensory neuropathy or neurovascular degeneration. Current treatments are focused on advanced vision-threatening disease and a single molecular target, vascular endothelial growth factor, has an approved therapy. We trace the evolution of understanding of DRD pathogenesis, identify new approaches to clinical assessment, trials infrastructure and design, and target identification to accelerate selection and evaluation of new therapeutics that will speed development of potentially curative interventions. Critically, the "Restoring Vision Moonshot" framework will address gaps in knowledge to be filled to achieve the goal of restoring sight and preventing vision loss in persons with diabetes.

Engineering CAR-T cells to activate small-molecule drugs in situ.

Chimeric antigen receptor (CAR)-T cells represent a major breakthrough in cancer therapy, wherein a patient's own T cells are engineered to recognize a tumor antigen, resulting in activation of a local cytotoxic immune response. However, CAR-T cell therapies are currently limited to the treatment of B cell cancers and their effectiveness is hindered by resistance from antigen-negative tumor cells, immunosuppression in the tumor microenvironment, eventual exhaustion of T cell immunologic functions and frequent severe toxicities. To overcome these problems, we have developed a novel class of CAR-T cells engineered to express an enzyme that activates a systemically administered small-molecule prodrug in situ at a tumor site. We show that these synthetic enzyme-armed killer (SEAKER) cells exhibit enhanced anticancer activity with small-molecule prodrugs, both in vitro and in vivo in mouse tumor models. This modular platform enables combined targeting of cellular and small-molecule therapies to treat cancers and potentially a variety of other diseases.

Awareness of Diabetic Retinopathy: Insight From the National Health and Nutrition Examination Survey.

INTRODUCTION: This study determines the prevalence and associated correlates of people unaware of their diabetic retinopathy diagnosis in the U.S. METHODS: Participants unaware of diabetic retinopathy from the National Health and Nutrition Examination Survey from 2005 to 2008 were identified. The prevalence of those unaware of their diabetic retinopathy diagnosis was determined. Descriptive statistics and logistic regression were used to determine correlates associated with being unaware of one's diabetic retinopathy diagnosis (completed in 2018‒2020). RESULTS: Among 5,563 participants aged ≥40 years who underwent fundus photography, the prevalence of those unaware of their diabetic retinopathy diagnosis was 10.6% (9.8 million). This included 23.1% of those with self-reported diabetes (2.9 million) and 6.8% of those who reported not having diabetes (6.9 million). Among participants reporting diabetes with photographic evidence of retinopathy, 70.1% were unaware. Among individuals with self-reported diabetes, correlates of being unaware of one's diabetic retinopathy diagnosis included diabetes diaganosis for ≥10 years (OR=3.15, 95% CI=1.78, 5.56), HbA1c ≥6.5% (OR=2.92, 95% CI=1.65, 5.18), and treatment with insulin only (OR=4.04, 95% CI=1.43, 11.39). Self-reported hypertension was associated with decreased odds of undiagnosed diabetic retinopathy (OR=0.48, 95% CI=0.28, 0.82). Among those without self-reported diabetes, correlates of being unaware of diabetic retinopathy included older age (OR=1.02, 95% CI=1.01, 1.04), male sex (OR=1.83, 95% CI=1.31, 2.56), Black race (OR=1.81, 95% CI=1.12, 2.92), Hispanic race/ethnicity (OR=1.60, 95% CI=1.14, 2.25), elevated blood pressure (OR=1.54, 95% CI=1.23, 1.93), current smoking (OR=1.74, 95% CI=1.21, 2.51), and history of stroke (OR=2.20, 95% CI=1.06, 4.58). CONCLUSIONS: A substantial proportion of individuals with diabetic retinopathy are unaware of the diagnosis. These data provide a path toward refining efforts to diagnose and treat diabetic retinopathy to decrease the burden of preventable blindness.

Insulin-like growth factor-2 regulates basal retinal insulin receptor activity.

The retinal insulin receptor (IR) exhibits basal kinase activity equivalent to that of the liver of fed animals, but unlike the liver, does not fluctuate with feeding and fasting; it also declines rapidly after the onset of insulin-deficient diabetes. The ligand(s) that determine basal IR activity in the retina has not been identified. Using a highly sensitive insulin assay, we found that retinal insulin concentrations remain constant in fed versus fasted rats and in diabetic versus control rats; vitreous fluid insulin levels were undetectable. Neutralizing antibodies against insulin-like growth factor 2 (IGF-2), but not insulin-like growth factor 1 (IGF-1) or insulin, decreased IR kinase activity in normal rat retinas, and depletion of IGF-2 from serum specifically reduced IR phosphorylation in retinal cells. Immunoprecipitation studies demonstrated that IGF-2 induced greater phosphorylation of the retinal IR than the IGF-1 receptor. Retinal IGF-2 mRNA content was 10-fold higher in adults than pups and orders of magnitude higher than in liver. Diabetes reduced retinal IGF-2, but not IGF-1 or IR, mRNA levels, and reduced IGF-2 and IGF-1 content in vitreous fluid. Finally, intravitreal administration of IGF-2 (mature and pro-forms) increased retinal IR and Akt kinase activity in diabetic rats. Collectively, these data reveal that IGF-2 is the primary ligand that defines basal retinal IR activity and suggest that reduced ocular IGF-2 may contribute to reduced IR activity in response to diabetes. These findings may have importance for understanding the regulation of metabolic and prosurvival signaling in the retina.