US youth perspectives on eye trauma and eye protection.

Eye injuries from sports, activities, and work are a leading cause of vision loss in youth. Most eye injuries can be prevented with protective eyewear. An open-ended survey on youth perspectives on eye trauma and protection was administered to the MyVoice Text Message Cohort of US youth ages 14-24 years. Qualitative, text message responses were coded using thematic analysis. The survey was distributed to 798 recipients; 641 (80.3%) responded. Many youth were concerned about the impact of excessive screen use (n = 278 [43.8%]) and sunlight or UV exposure (n = 239 [37.6%]) on their eye health. Fewer were concerned about injury from sports and activities (n = 115 [18.1%]) or job-related eye risks (n = 77 [12.1%]). The most common actions that youth took to protect their eyes included sun protection (eg, sunglasses; n = 300 [47.2%]), refractive correction (eg, glasses, contacts; n = 195 [30.7%]) and screen protection (eg, blue light blocking glasses; n = 159 [25.0%]). Fewer wore eye protection for sports or activities (n = 54 [8.5%]) or work (n = 41 [6.5%]). Youth concerns about eye injury from screens and sunlight are misaligned with the main causes of vision loss in this population, suggesting that public health education is needed to promote optimal eye safety.

A Qualitative Assessment of the Experiences with Eye Health and Barriers to Eyeglasses among U.S. Youth.

SIGNIFICANCE: Uncorrected refractive error is the main cause of visual impairment in U.S. youth and has profound impacts on individuals and society. Identifying and addressing barriers to eyeglasses in this population are critical to maximize youth academic performance, workplace productivity, and quality of life. PURPOSE: We aimed to understand youth experiences with eye health, assess the value that youth place on vision, and identify barriers to refractive correction directly from a nationwide sample of youth to inform interventions to address uncorrected refractive error in this population. METHODS: An open-ended poll was distributed to the MyVoice Text Message Cohort of U.S. youth eliciting youth experiences with eye health and barriers to wearing eyeglasses. Text message responses were coded using grounded theory. RESULTS: Of 1204 recipients, 88.3% (n = 1063) responded. The mean age ± standard deviation was 20.3 ± 2.4 years, 58.8% (n = 625) were male, 74.0% (n = 787) were White, and 41.4% (n = 440) reported low socioeconomic status. Four major themes emerged from the open-ended responses: (1) many youth have experienced problems with their eyes or eyesight (n = 699 [65.8%]); (2) many youth value their eyesight highly (n = 905 [85.1%]; e.g., "Eyesight is one of the most important aspects of my health, particularly in our digital world…"); (3) common reasons youth might not wear glasses even if they need them include concerns over appearance (n = 553 [52.0%]; e.g., "I thought every pair made me look ugly…"), cost (n = 171 [16.1%]), inconvenience (n = 166 [15.6%]), and discomfort (n = 104 [9.8%]); and (4) youth are open to purchasing eyeglasses online (n = 539 [50.7%]). CONCLUSIONS: Appearance, cost, inconvenience, and discomfort are critical barriers to wearing eyeglasses among U.S. youth. A multisectoral response is necessary to address these barriers.

Periorbital edema as the presenting sign of protein-losing enteropathy from excessive cow's milk intake.

We report the case of a 15-month-old girl who presented with bilateral, positional periorbital edema, systemic hypoalbuminemia, and profound iron deficiency caused by excessive cow's milk intake. Her symptoms rapidly improved with reduction of cow's milk intake and iron supplementation.

Treatment of Congenital Ptosis in Infants With Associated Amblyopia Using a Frontalis Muscle Flap Eyelid Reanimation Technique.

PURPOSE: To determine the efficacy of a frontalis muscle flap eyelid reanimation technique for correction of severe congenital ptosis and associated amblyopia in infants. METHODS: The authors performed a retrospective chart review of patients 12 months of age or younger with unilateral or bilateral congenital ptosis and associated amblyopia or deemed at high risk for amblyopia due to visual deprivation. Following ptosis repair via a frontalis muscle flap technique, primary outcomes of postoperative eyelid position and amblyopia reversal were assessed. RESULTS: Seventeen eyes of 12 participants were included for study. Seven of these patients had simple congenital ptosis, and the remainder had ptosis as part of a syndrome. Nine were diagnosed with amblyopia preoperatively, and the remaining 3 were too young for acuity testing but had occlusion of the visual axis by the ptotic eyelid in primary gaze. Postoperatively, the mean margin-to-reflex distance 1 was 2.4 mm (range: 0.0-4.0), and 9 patients (75%) demonstrated no evidence of amblyopia. Only 2 patients had eyelid asymmetry greater than 2 mm, which in both cases was due to lack of frontalis activation by the patient secondary to ongoing visual impairment. The most common complication was lagophthalmos in 6 eyes (35.3%), with no significant associated surface keratopathy. CONCLUSIONS: The frontalis muscle flap technique may offer a new and effective approach to treating infants with severe congenital ptosis causing poor eyelid excursion and associated amblyopia while avoiding use of an implant.

Phenotypic Variation in a Four-Generation Family with Aniridia Carrying a Novel PAX6 Mutation.

Aniridia is a congenital disease that affects almost all eye structures and is primarily caused by loss-of-function mutations in the PAX6 gene. The degree of vision loss in aniridia varies and is dependent on the extent of foveal, iris, and optic nerve hypoplasia and the presence of glaucoma, cataracts, and corneal opacification. Here, we describe a 4-generation family in which 7 individuals across 2 generations carry a novel disease-causing frameshift mutation (NM_000280.4(PAX6):c.565TC>T) in PAX6. This mutation results in an early stop codon in exon 8, which is predicted to cause nonsense-mediated decay of the truncated mRNA and a functionally null PAX6 allele. Family members with aniridia showed differences in multiple eye phenotypes including iris and optic nerve hypoplasia, congenital and acquired corneal opacification, glaucoma, and strabismus. Visual acuity ranged from 20/100 to less than 20/800. Patients who required surgical intervention for glaucoma or corneal opacification had worse visual outcomes. Our results show that family members carrying a novel PAX6 frameshift mutation have variable expressivity, leading to different ocular comorbidities and visual outcomes.

Angle closure glaucoma in congenital ectropion uvea.

PURPOSE: Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. OBSERVATIONS: Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). CONCLUSIONS AND IMPORTANCE: Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

TMSB4Y is a candidate tumor suppressor on the Y chromosome and is deleted in male breast cancer.

Male breast cancer comprises less than 1% of breast cancer diagnoses. Although estrogen exposure has been causally linked to the development of female breast cancers, the etiology of male breast cancer is unclear. Here, we show via fluorescence in situ hybridization (FISH) and droplet digital PCR (ddPCR) that the Y chromosome was clonally lost at a frequency of ~16% (5/31) in two independent cohorts of male breast cancer patients. We also show somatic loss of the Y chromosome gene TMSB4Y in a male breast tumor, confirming prior reports of loss at this locus in male breast cancers. To further understand the function of TMSB4Y, we created inducible cell lines of TMSB4Y in the female human breast epithelial cell line MCF-10A. Expression of TMSB4Y resulted in aberrant cellular morphology and reduced cell proliferation, with a corresponding reduction in the fraction of metaphase cells. We further show that TMSB4Y interacts directly with ß-actin, the main component of the actin cytoskeleton and a cell cycle modulator. Taken together, our results suggest that clonal loss of the Y chromosome may contribute to male breast carcinogenesis, and that the TMSB4Y gene has tumor suppressor properties.

MACROD2 overexpression mediates estrogen independent growth and tamoxifen resistance in breast cancers.

Tamoxifen is effective for treating estrogen receptor-alpha (ER) positive breast cancers. However, few molecular mediators of tamoxifen resistance have been elucidated. Here we describe a previously unidentified gene, MACROD2 that confers tamoxifen resistance and estrogen independent growth. We found MACROD2 is amplified and overexpressed in metastatic tamoxifen-resistant tumors. Transgene overexpression of MACROD2 in breast cancer cell lines results in tamoxifen resistance, whereas RNAi-mediated gene knock down reverses this phenotype. MACROD2 overexpression also leads to estrogen independent growth in xenograft assays. Mechanistically, MACROD2 increases p300 binding to estrogen response elements in a subset of ER regulated genes. Primary breast cancers and matched metastases demonstrate MACROD2 expression can change with disease evolution, and increased expression and amplification of MACROD2 in primary tumors is associated with worse overall survival. These studies establish MACROD2 as a key mediator of estrogen independent growth and tamoxifen resistance, as well as a potential novel target for diagnostics and therapy.

Single copies of mutant KRAS and mutant PIK3CA cooperate in immortalized human epithelial cells to induce tumor formation.

The selective pressures leading to cancers with mutations in both KRAS and PIK3CA are unclear. Here, we show that somatic cell knockin of both KRAS G12V and oncogenic PIK3CA mutations in human breast epithelial cells results in cooperative activation of the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways in vitro, and leads to tumor formation in immunocompromised mice. Xenografts from double-knockin cells retain single copies of mutant KRAS and PIK3CA, suggesting that tumor formation does not require increased copy number of either oncogene, and these results were also observed in human colorectal cancer specimens. Mechanistically, the cooperativity between mutant KRAS and PIK3CA is mediated in part by Ras/p110α binding, as inactivating point mutations within the Ras-binding domain of PIK3CA significantly abates pathway signaling. In addition, Pdk1 activation of the downstream effector p90RSK is also increased by the combined presence of mutant KRAS and PIK3CA. These results provide new insights into mutant KRAS function and its role in carcinogenesis.

The growth response to androgen receptor signaling in ERα-negative human breast cells is dependent on p21 and mediated by MAPK activation.

INTRODUCTION: Although a high frequency of androgen receptor (AR) expression in human breast cancers has been described, exploiting this knowledge for therapy has been challenging. This is in part because androgens can either inhibit or stimulate cell proliferation in pre-clinical models of breast cancer. In addition, many breast cancers co-express other steroid hormone receptors that can affect AR signaling, further obfuscating the effects of androgens on breast cancer cells. METHODS: To create better-defined models of AR signaling in human breast epithelial cells, we took estrogen receptor (ER)-α-negative and progesterone receptor (PR)-negative human breast epithelial cell lines, both cancerous and non-cancerous, and engineered them to express AR, thus allowing the unambiguous study of AR signaling. We cloned a full-length cDNA of human AR, and expressed this transgene in MCF-10A non-tumorigenic human breast epithelial cells and MDA-MB-231 human breast-cancer cells. We characterized the responses to AR ligand binding using various assays, and used isogenic MCF-10A p21 knock-out cell lines expressing AR to demonstrate the requirement for p21 in mediating the proliferative responses to AR signaling in human breast epithelial cells. RESULTS: We found that hyperactivation of the mitogen-activated protein kinase (MAPK) pathway from both AR and epidermal growth factor receptor (EGFR) signaling resulted in a growth-inhibitory response, whereas MAPK signaling from either AR or EGFR activation resulted in cellular proliferation. Additionally, p21 gene knock-out studies confirmed that AR signaling/activation of the MAPK pathway is dependent on p21. CONCLUSIONS: These studies present a new model for the analysis of AR signaling in human breast epithelial cells lacking ERα/PR expression, providing an experimental system without the potential confounding effects of ERα/PR crosstalk. Using this system, we provide a mechanistic explanation for previous observations ascribing a dual role for AR signaling in human breast cancer cells. As previous reports have shown that approximately 40% of breast cancers can lack p21 expression, our data also identify potential new caveats for exploiting AR as a target for breast cancer therapy.

Mutation of a single allele of the cancer susceptibility gene BRCA1 leads to genomic instability in human breast epithelial cells.

Biallelic inactivation of cancer susceptibility gene BRCA1 leads to breast and ovarian carcinogenesis. Paradoxically, BRCA1 deficiency in mice results in early embryonic lethality, and similarly, lack of BRCA1 in human cells is thought to result in cellular lethality in view of BRCA1's essential function. To survive homozygous BRCA1 inactivation during tumorigenesis, precancerous cells must accumulate additional genetic alterations, such as p53 mutations, but this requirement for an extra genetic "hit" contradicts the two-hit theory for the accelerated carcinogenesis associated with familial cancer syndromes. Here, we show that heterozygous BRCA1 inactivation results in genomic instability in nontumorigenic human breast epithelial cells in vitro and in vivo. Using somatic cell gene targeting, we demonstrated that a heterozygous BRCA1 185delAG mutation confers impaired homology-mediated DNA repair and hypersensitivity to genotoxic stress. Heterozygous mutant BRCA1 cell clones also showed a higher degree of gene copy number loss and loss of heterozygosity in SNP array analyses. In BRCA1 heterozygous clones and nontumorigenic breast epithelial tissues from BRCA mutation carriers, FISH revealed elevated genomic instability when compared with their respective controls. Thus, BRCA1 haploinsufficiency may accelerate hereditary breast carcinogenesis by facilitating additional genetic alterations.

PIK3CA mutations and EGFR overexpression predict for lithium sensitivity in human breast epithelial cells.

A high frequency of somatic mutations has been found in breast cancers within the gene encoding the catalytic p110α subunit of PI3K, PIK3CA. Using isogenic human breast epithelial cells, we have previously demonstrated that oncogenic PIK3CA "hotspot" mutations predict for response to the toxic effects of lithium. However, other somatic genetic alterations occur within this pathway in breast cancers, and it is possible that these changes may also predict for lithium sensitivity. We overexpressed the epidermal growth factor receptor (EGFR) into the non-tumorigenic human breast epithelial cell line MCF-10A, and compared these cells to isogenic cell lines previously created via somatic cell gene targeting to model Pten loss, PIK3CA mutations, and the invariant AKT1 mutation, E17K. EGFR overexpressing clones were capable of cellular proliferation in the absence of EGF and were sensitive to lithium similar to the results previously seen with cells harboring PIK3CA mutations. In contrast, AKT1 E17K cells and PTEN -/- cells displayed resistance or partial sensitivity to lithium, respectively. Western blot analysis demonstrated that lithium sensitivity correlated with significant decreases in both PI3K and MAPK signaling that were observed only in EGFR overexpressing and mutant PIK3CA cell lines. These studies demonstrate that EGFR overexpression and PIK3CA mutations are predictors of response to lithium, whereas Pten loss and AKT1 E17K mutations do not predict for lithium sensitivity. Our findings may have important implications for the use of these genetic lesions in breast cancer patients as predictive markers of response to emerging PI3K pathway inhibitors.

Reduced mismatch repair of heteroduplexes reveals "non"-interfering crossing over in wild-type Saccharomyces cerevisiae.

Using small palindromes to monitor meiotic double-strand-break-repair (DSBr) events, we demonstrate that two distinct classes of crossovers occur during meiosis in wild-type yeast. We found that crossovers accompanying 5:3 segregation of a palindrome show no conventional (i.e., positive) interference, while crossovers with 6:2 or normal 4:4 segregation for the same palindrome, in the same cross, do manifest interference. Our observations support the concept of a "non"-interference class and an interference class of meiotic double-strand-break-repair events, each with its own rules for mismatch repair of heteroduplexes. We further show that deletion of MSH4 reduces crossover tetrads with 6:2 or normal 4:4 segregation more than it does those with 5:3 segregation, consistent with Msh4p specifically promoting formation of crossovers in the interference class. Additionally, we present evidence that an ndj1 mutation causes a shift of noncrossovers to crossovers specifically within the "non"-interference class of DSBr events. We use these and other data in support of a model in which meiotic recombination occurs in two phases-one specializing in homolog pairing, the other in disjunction-and each producing both noncrossovers and crossovers.