Obstruction of the Tear Drainage Altered Lacrimal Gland Structure and Function.

Purpose: Orbital glands and drainage conduits are two distinct entities that constitute the lacrimal apparatus system, the malfunction of which leads to a range of ocular surface disorders. Despite the close functional relationship, how the two parts interact under pathophysiological conditions has not been directly tested. The study aims to investigate the lacrimal gland (LG) structural and functional changes upon the drainage system obstruction, thus, testing their function link. Methods: Dacryocystectomy was performed in C57BL/6 mice to create a surgical model for tear duct (TD) obstruction (STDOB). Prickle1 mutant line with congenital nasolacrimal duct dysplasia serves as a genetic model for TD obstruction (GTDOB). Alterations of the LG and the ocular surface in tear duct obstruction mice were examined. Results: STDOB and GTDOB mice showed similar ocular surface phenotypes, including epiphora, corneal epithelial defects, and conjunctival goblet cell abnormalities. At the molecular and cellular levels, aberrant secretory vesicle fusion of the LG acinar cells was observed with altered expression and localization of Rab3d, Vamp8, and Snap23, which function in membrane fusion. LG secretion was also altered in that lactoferrin, lipocalin2, and lysozyme expression were increased in both LG and tears. Furthermore, STDOB and GTDOB mice exhibited similar LG transcription profiles. Conclusions: Physical obstruction of tear drainage in STDOB or GTDOB mice leads to LG dysfunction, suggesting a long-distance interaction between the tear drainage conduits and the LG. We propose that various components of the lacrimal apparatus should be considered an integral unit in diagnosing and treating ocular surface diseases.

Proteomic analysis reveals the heterogeneity of metabolic reprogramming in lacrimal gland tumors.

Lacrimal gland adenoid cystic carcinoma (ACC) is associated with high recurrence and mortality rates. Many recent studies have focused on the clinical features of the disease, and a better understanding of its underlying molecular mechanisms may help guide future treatment strategies. For proteomics quantitation, we analyzed normal tissues, benign tumor tissues and ACC tissues by LC-MS/MS with Tandem mass tags (TMTs) labeling. Bioinformatics analysis of the KEGG pathway found that, compared with normal tissues, the expression levels of major proteins related to cell metabolism were lower in benign tumors and cancer tissues of the lacrimal gland. In addition, we also performed IHC staining to verify the expression of representative proteins in tissue samples. All of these results indicated that compared with normal tissues, lacrimal gland tumors had unique metabolic reprogramming characteristics. Further Short Time-series Expression Miner (STEM) analysis revealed that glycine, serine and threonine metabolism in ACC tissues was significantly enhanced compared with that in normal tissues and benign tumor tissues. This finding suggested that glycine, serine and threonine metabolism might be the key to the malignant transformation of ACC; thus, assessing the metabolism in these tissues could be an effective approach enabling the early diagnosis of ACC, and the proteins involved in these metabolic pathways could represent therapeutic targets.

Vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1 alpha (HIF-1ɑ) in lacrimal gland Adenoid cystic carcinoma: Correlation with clinical outcome.

PURPOSE: VEGF and HIF-1α are important regulators of angiogenesis, overexpressed in various tumors. Lacrimal gland Adenoid cystic carcinoma (ACC) is a malignant tumor whose angiogenic properties remain unexplored. This study was designed to evaluate the expression of HIF-1α and VEGF in lacrimal gland ACC. METHODS: VEGF and HIF-1α immunoexpression was undertaken in 30 lacrimal gland ACC cases. mRNA expression of VEGF and HIF-1α was analysed in 17 cases by quantitative real time PCR. The results obtained were correlated with clinicopathological features and survival of the patients to determine the prognostic significance. RESULTS: Immunoexpression of HIF-1α and VEGF was seen in 36.6% and 46.6% ACC cases. HIF-1α expression showed significant association with advanced T-stage (P = 0.001) and VEGF with intracranial extension (P = 0.014) and solid histological pattern (P = 0.045). HIF-1α mRNA expression was seen in 29.4% cases and showed significant association with perineural invasion (P = 0.027). Recurrence occurred in 60%, distant metastasis in 20% and death in 20% cases. Survival analysis revealed that patients with HIF-1α, VEGF immunoexpression, solid histological pattern, perineural invasion, bone erosion, intracranial extension, metastasis, advanced T-stage, and exenteration had poor survival. On multivariate analysis VEGF immunoexpression (hazard ratio, 16.785; 95% confidence interval, 1.872-150.495; P = 0.012) was the most significant poor prognostic factor. CONCLUSIONS: This study demonstrates that VEGF is a potential predictor for poor clinical outcome in lacrimal gland Adenoid cystic carcinoma.

The FcεRI signaling pathway is involved in the pathogenesis of lacrimal gland benign lymphoepithelial lesions as shown by transcriptomic analysis.

This study aimed to analyze the role of the FcepsilonRI (FcεRI) signaling pathway in the pathogenesis of benign lymphoepithelial lesion of lacrimal gland (LGBLEL). Transcriptomic analysis was performed on LGBLEL and orbital cavernous hemangioma (CH) patients diagnosed via histopathology in Beijing Tongren Hospital, Capital Medical University, between July 2010 and October 2013. Four LGBLEL and three orbital CH patients, diagnosed between October 2018 and August 2019, were randomly selected as experimental and control groups, respectively. RT-PCR, immunohistochemical staining, and western blotting were used to verify genes and proteins related to the FcεRI signaling pathway. Transcriptomic analysis showed that the FcεRI signaling pathway was upregulated in the LGBLEL compared with the CH group. The mRNA expression levels of important genes including SYK, p38, JNK, PI3K, and ERK were significantly increased in the LGBLEL group (P = 0.0066, P = 0.0002, P = 0.0003, P < 0.0001, P < 0.0001, respectively). Immunohistochemical staining results showed that SYK, p38, and ERK were positively expressed in LGBLEL, while JNK and PI3K were not. The protein contents of P-SYK, P-p38, P-JNK, P-PI3K, and P-ERK were significantly higher in the LGBLEL than in the CH group (P = 0.0169, P = 0.0074, P = 0.0046, P = 0.0157, P = 0.0156, respectively). The FcεRI signaling pathway participates in the pathogenesis of LGBLEL.

Prognostic impact of Notch1 receptor and clinicopathological High-Risk Predictors in lacrimal gland adenoid cystic carcinoma.

PURPOSE: Adenoid Cystic Carcinoma (ACC) is an aggressive malignant lacrimal gland tumour associated with poor prognosis. Aberrant Notch signalling has been investigated in various tumours. However, very few studies on Notch signalling in lacrimal gland ACC are reported. The aim of the present study was to evaluate the status of Notch1 receptor and activated Notch1 (NICD1) in lacrimal gland ACC and to correlate it with high-risk clinicopathological features. METHODS: A total of 23 cases of histopathologically proven lacrimal gland ACC, who underwent surgical treatment, were included in this study. Expression of Notch1 receptor and NICD1 was evaluated by immunohistochemistry on formalin fixed paraffin embedded tissues. The results obtained were correlated with clinicopathological high-risk features and survival of the patients. Kaplan-Meier survival and multivariate analysis was performed to determine the prognostic significance. RESULTS: Overexpression of Notch1 receptor and NICD1 was observed in 65% and 39% of lacrimal gland ACC cases, respectively. On Kaplan-Meier survival analysis, patients with Notch1 receptor overexpression had reduced disease free survival. On univariate analysis, male gender, bone erosion, perineural invasion, solid histologic pattern, intracranial extension and advanced tumour stage were also indicators of poor prognosis. On multivariate analysis bone erosion was the most significant poor prognostic indicator. CONCLUSION: Our study demonstrates that overexpression of Notch1 receptor plays a critical role in the biology and aggressive behaviour of lacrimal gland ACC. Bone erosion, solid histologic pattern, advanced T stage, perineural invasion and intracranial extension are other high-risk clinicopathological predictors of lacrimal gland ACC.

Ocular PEComas are frequently melanotic and TFE3-translocated: report of two cases including the first description of PRCC-TFE3 fusion in PEComa.

Ocular perivascular epithelioid cell tumor (PEComa) is exceedingly rare. We reported two examples involving the choroid and subconjunctival tissue, respectively, in patients aged 17 and 20 years. Both tumors comprised packets and sheets of large polygonal cells with moderately pleomorphic nuclei and prominent nucleoli, traversed by delicate fibrovascular septa. Melanin pigmentation was present in one case. The tumors showed HMB45 and TFE3 immunoreactivity. TFE3 gene translocation was confirmed by FISH break-apart probes. RNA seq revealed PRCC-TFE3 and NONO-TFE3 fusions, with the former representing the first description of PRCC-TFE3 in PEComa. Critical reappraisal of the reported cases showed that ocular PEComa frequently affected young patents with melanin pigmentation, frequent TFE3 protein expression, and/or TFE3 gene translocation. No recurrence or metastasis was reported after complete excision despite the presence of cytologic atypia.

Evaluation of Ocular Parameters in Adult Patients with Celiac Disease.

PURPOSE: To evaluate ophthalmic parameters in adult celiac patients. METHODS: This cross-sectional study included 31 celiac patients (58 eyes) and 25 healthy controls (50 eyes). Tear break up time (TBUT), schirmer test were measured; corneal thickness, anterior chamber parameters were obtained using scheimpflug camera; retinal nerve fiber layer thickness (RNFL) evaluated by using spectral domain optical cohorence tomography. RESULTS: There were no statistically significant differences between the groups in terms of gender, age, and intraocular pressure (p > .05). Schirmer's test results and TBUT were significantly lower in celiac patients (p < .001, p < .001). Additionally, the superior RNFL was significantly thinner (p = .017), nasal RNFL thicker (p = .007), and anterior chamber depth larger (p = .037) in celiac patients. The tissue transglutaminase 2 IgA antibody and superior RNFL were negatively correlated (r = -0.394, p = .012). The anterior chamber volume and anti-gliadin IgA antibody were positively correlated (r = 0.369 p = .027). CONCLUSION: Celiac disease affects Schirmer's test results, TBUT, segmental RNFL thickness, and anterior chamber parameters. Ocular parameters might be affected in celiac disease especially in the presence of high antibody titer.

Malformation of Tear Ducts Underlies the Epiphora and Precocious Eyelid Opening in Prickle 1 Mutant Mice: Genetic Implications for Tear Duct Genesis.

Purpose: Obstruction of the tear drainage causes a range of ocular surface disorders. Hitherto, the genetics of tear duct development and obstruction has been scarcely explored, and related animal models are lacking. This study aims to study the potential role of the Wnt/PCP pathway mediated by Prickle 1 in tear duct development and diseases. Methods: A severe hypomorphic Prickle 1 mutant was generated. Histology and immunohistochemistry were performed to compare wild type, Prickle 1 hypomorphic, and null mutant tear ducts. In situ hybridization was conducted to identify the signaling components in the developing tear ducts. Three-dimensional (3D) reconstruction was used to detect the human embryonic tear duct. Results: Here, we report that a severe Prickle 1 hypomorph mouse line exhibited epiphora. This phenotype was due to the blockage of the tear drainage by incompletely formed nasolacrimal duct (NLD) and lacrimal canaliculi (LC), which also causes precocious eyelid opening. We observed a dose-dependent requirement of Prickle 1 for tear duct outgrowth. An investigation of the expression of Wnt/PCP core genes demonstrated a subset of PCP signaling components expressed in the developing tear duct. Furthermore, Prickle 1 is not required for the expression of Fgfr2/Fgf10 and p63 genes, which are associated with the NLD and LC hypoplasia in humans. Last, we showed that Prickle 1 expression in the developing tear drainage system is conserved between mice and humans. Conclusions: The study suggests that malformed tear ducts caused by disruption of Prickle 1 underlies the epiphora and precocious eyelid opening.

Deterioration of contrast sensitivity in eyes with epiphora due to lacrimal passage obstruction.

PURPOSE: Epiphora causes deterioration in contrast sensitivity in some eye diseases. This study was conducted to investigate contrast sensitivity in eyes with epiphora caused by lacrimal passage obstruction. METHODS: This single-center, prospective case series enrolled 57 patients with unilateral lacrimal passage obstruction. The best-corrected visual acuity (BCVA), contrast sensitivity function, and lower tear meniscus of the affected and contralateral unaffected eyes were compared. The area under the log contrast sensitivity function (AULCSF) was calculated. RESULTS: The BCVA did not significantly differ between the affected and contralateral eyes, while the AULCSF was significantly lower in the affected eyes than that in the contralateral eyes (median 1.35, interquartile range 1.22-1.44 vs. median 1.36, interquartile range 1.28-1.46, P = 0.032). Lower tear meniscus parameters were significantly higher in the affected eyes than those in the contralateral eyes (P < 0.005). CONCLUSIONS: The contrast sensitivity function is significantly diminished in eyes with epiphora caused by lacrimal passage obstruction.

Clinical Implications of Goblet Cells in Dacryoadenosis and Normal Human Lacrimal Glands.

PURPOSE: The purpose of this study was to investigate an enlarged dacryoadenotic lacrimal gland and normal lacrimal glands for the presence of goblet cells (mucocytes). DESIGN: Retrospective clinicopathologic series. METHODS: An enlarged lacrimal gland (dacryoadenosis) without obvious histopathologic alterations was extensively evaluated histochemically, immunohistochemically, and ultrastructurally to detect the presence of goblet cells and to compare the findings with those in five normal lacrimal glands. RESULTS: Granular, zymogen-rich pyramidal acinar cells in normal glands predominated over a previously not reported subpopulation of nongranular, pale-staining cells in both dacryoadenotic and normal lacrimal glands. These cells histochemically stained positively with mucicarmine and Alcian blue. Immunohistochemical and electron microscopic evaluations established that there was a displacement or replacement of cytoplasmic gross cystic disease fluid protein-15 and CK 7-positive tonofilaments in the pale acinar cells by myriad mucus granules. The goblet cells constituted approximately 2% of the normal acinar cells and 5% of dacryoadenotic acinar cells. A depletion of myoepithelial cells and ectopic intra-acinar ductular cells were also observed in dacryoadenosis. CONCLUSION: Dacryoadenosis is caused by an increase in the number of acini without individual acinar cell hyperplasia. A normal cytologic feature of the lacrimal gland is the presence of acinar goblet cells that had been long overlooked; they are increased in number in dacryoadenosis. Intra-acinar ductular cells and the scattered loss of myoepithelial cells are other abnormalities in dacryoadenosis. The presence of lacrimal gland goblet cells may have physiologic implications for the precorneal tear film and its derangements as well as for the histogenesis of mucus-producing carcinomas.

N-Glycanase 1 Transcriptionally Regulates Aquaporins Independent of Its Enzymatic Activity.

Patients with pathogenic mutations in NGLY1 cannot make tears and have global developmental delay and liver dysfunction. Traditionally, NGLY1 cleaves intact N-glycans from misfolded, retrotranslocated glycoproteins before proteasomal degradation. We demonstrate that Ngly1-null mouse embryonic fibroblasts, NGLY1 knockout human cells, and patient fibroblasts are resistant to hypotonic lysis. Ngly1-deficient mouse embryonic fibroblasts swell slower and have reduced aquaporin1 mRNA and protein expression. Ngly1 knockdown and overexpression confirms that Ngly1 regulates aquaporin1 and hypotonic cell lysis. Patient fibroblasts and NGLY1 knockout cells show reduced aquaporin11 mRNA, supporting NGLY1 as regulating expression of multiple aquaporins across species. Complementing Ngly1-deficient cells with catalytically inactive NGLY1 (p.Cys309Ala) restores normal hypotonic lysis and aquaporin1 protein. We show that transcription factors Atf1/Creb1 regulate aquaporin1 and that the Atf1/Creb1 signaling pathway is disrupted in Ngly1-deficient mouse embryonic fibroblasts. These results identify a non-enzymatic, regulatory function of NGLY1 in aquaporin transcription, possibly related to alacrima and neurological symptoms.

Corneal Sensory Experience via Transient Receptor Potential Vanilloid 1 Accelerates the Maturation of Neonatal Tearing.

Tearing maturates rapidly after birth, and external environmental challenges play a key role in promoting lacrimal functional maturation. However, little is known about the facilitative factors underlying this developmental process or the potential of application of these factors to treat hypofunction of the lacrimal gland. In this study, eye opening and the subsequent ocular surface sensory experience, which is thought to be involved in postnatal maturation of lacrimal function, were investigated. Our results demonstrated that eye opening after birth is essential for the maturation of neonatal tearing. The maturation process of lacrimal function is dependent on the ocular surface sensory experience via transient receptor potential cation channel subfamily member 1 after birth. This study provides, for the first time, important evidence of the sensory experience of the ocular surface in relation to the maturation of functional tear secretion during the postnatal period.

Investigating the potential of carboxymethyl pullulan for protecting the rabbit eye from systematically induced precorneal tear film damage.

The present investigation was aimed to develop a rabbit model for protecting the rabbit eye from systematically induced precorneal tear film (PTF) damage, evaluation of carboxymethyl pullulan for its protective action against PTF damage and its curative potential. For the same, pullulan was modified by carboxymethylation and structural modification was confirmed by spectral attributes. Further, the carboxymethyl pullulan (CMP) solutions (0.1-2.0%, w/v) were evaluated for their physical properties and its concentration 1.5% (w/v) was found to fit the criterion to prepare an eye solution. The safety and non-toxicity of CMP (1.5%, w/v) eye solution was confirmed by HET-CAM method and rabbit eye irritation test. Further, a systematic rabbit eye model was developed that mimic PTF damage in day to day life. Therefore, three levels of PTF damage were developed equating symptoms of damage due to high temperature (level I) or long term mobile use (level II) or heavy air pollution (level III). Thus, a representative model with benzalkonium chloride (BAC, 0.1% v/v, 0.2% v/v and 0.3% v/v), administered two drops twice a day for two days to develop level I, level II and level III eye damage. The CMP (1.5%, w/v) eye solution possessed a protective potential against level I and II PTF damage. The rabbit eyes remained unharmed and comparable with the normal control during the complete experimental period. Additionally, CMP (1.5%, w/v) eye solution has shown early fast recovery (8 days) from PTF damage induced by instillation of PTF damage agent (BAC). Carboxymethyl pullulan eye protective solution has normalized the tear film stability in rabbit eye model. It is established from the present work that, carboxymethyl pullulan has protective action against precorneal tear film damage and it potentiates the early recovery too.

INI1/SMARCB1-Deficient Carcinoma (Rhabdoid Tumor) of the Lacrimal Gland.

Integrase interactor 1 (INI1) is a tumor suppressor gene that is ubiquitously expressed in all nucleated cells. The loss of INI1 protein activity was first demonstrated in aggressive pediatric tumors, including atypical teratoid/rhabdoid (AT/RT) tumor of the central nervous system and malignant rhabdoid tumor of the kidney. Subsequently, INI1 deficiency was discovered in other pediatric and some adult neoplasms. The spectrum of INI1-negative tumors includes a wide variety of neoplasms that occur over a wide age range, are variably aggressive, and have a variable rhabdoid component on histopathologic evaluation. In this report, the authors describe a 27-year-old gravid woman with INI1-deficient carcinoma of the lacrimal gland, previously not described in this location.

Ocular Adnexal Amyloidosis: A Mass Spectrometric Analysis.

PURPOSE: Ocular adnexal amyloidosis (OAA) may represent localized manifestation of an underlying systemic process. Accurate identification of the amyloid fibrils can guide the systemic evaluation and treatment. The aim of this study was to characterize subtypes of OAA using immunohistochemistry and mass spectrometric analysis and to correlate with ocular involvement and systemic association. DESIGN: Retrospective case series. METHODS: Review of patients with OAA subtyped by immunohistochemistry and mass spectrometric analysis at the Cleveland Clinic from June 1995 to June 2017. RESULTS: While immunohistochemistry identified AL amyloid protein in 67% (4/6) of specimens tested, mass spectrometry identified AL amyloid protein in all specimens (10/10). AL lambda was identified in 5 (50%) samples, kappa in 3 (30%), and both kappa and lambda light chains in 2 (20%). The 5 cases of conjunctival amyloidosis were either AL lambda only (3 cases) or both lambda and kappa (2 cases). There were 3 cases that had associated systemic involvement. Two of these had eyelid skin involvement and AL kappa amyloidosis and the other patient had uveal involvement and AL lambda amyloidosis. CONCLUSIONS: Primary amyloidosis-AL is the most common form diagnosed by mass spectrometric analysis in patients with OAA. Immunohistochemistry is ineffective in the characterization of the amyloid deposits in a significant number of cases. Evaluation to exclude systemic involvement or associated underlying lymphoproliferative disorder is warranted.

Recurrent rearrangements of the PLAG1 and HMGA2 genes in lacrimal gland pleomorphic adenoma and carcinoma ex pleomorphic adenoma.

PURPOSE: Lacrimal gland tumours constitute a wide spectrum of neoplastic lesions that are histologically similar to tumours of the salivary gland. In the salivary gland, pleomorphic adenoma (PA) is frequently characterized by recurrent chromosomal rearrangements of the PLAG1 and HMGA2 genes, a genetic feature retained in carcinoma ex pleomorphic adenoma (ca-ex-PA) that makes it possible to distinguish ca-ex-PA from de novo carcinomas. However, whether PLAG1 and HMGA2 gene rearrangements are found in lacrimal gland PA and ca-ex-PA is not known. METHODS: Twenty-one lacrimal gland PAs and four ca-ex-PAs were retrospectively reviewed and subjected to break-apart fluorescence in situ hybridization (FISH) for rearrangements of the PLAG1 gene. Cases without PLAG1 abnormalities were subjected to HMGA2 break-apart FISH. Immunohistochemical staining for PLAG1 and HMGA2 protein was performed and correlated with gene status. RESULTS: Sixteen of 21 PAs showed rearrangement of PLAG1 and were all positive for PLAG1 protein. Two of the remaining five PAs showed rearrangement of HMGA2 and were the only cases positive for HMGA2 with immunohistochemistry. The three FISH-negative PAs expressed PLAG1 protein. All four ca-ex-PAs showed rearrangement of PLAG1 and expressed PLAG1 protein. None of the de novo carcinomas showed rearrangement of either of the two genes or expression of the two proteins. CONCLUSION: Rearrangement of PLAG1 and HMGA2 and expression of the corresponding proteins are frequent and specific findings in lacrimal gland PA and ca-ex-PA. The mechanism for PLAG1 overexpression in FISH-negative PAs is yet to be clarified.

Melanorrhea: Noncontiguous spread of palpebral conjunctival melanoma to the nasolacrimal duct.

A 42-year-old Asian Indian male with a history of conjunctival melanoma in the left eye presented with a recurrent tumor in the upper tarsal conjunctiva. The tumor was completely excised under margin control, followed by two-staged eyelid reconstruction. During the second stage of the eyelid reconstruction, a brown-colored discharge was noted at the punctum, which on cytology was confirmatory of melanoma. Left dacryocystectomy with en bloc nasolacrimal duct (NLD) excision was performed. Histopathology demonstrated infiltration of the NLD by the tumor with no presence of melanoma in the lacrimal sac. Lacrimal oncorrhea is a term used to describe tumor spread by free-floating cells in the tear film. All conjunctival tumors carry a risk of tumor spread by oncorrhea.