Retinoblastoma is the most common intraocular cancer in children. While the primary tumor can often be treated by local or systemic chemotherapy, metastatic dissemination is generally resistant to therapy and remains a leading cause of pediatric cancer death in much of the world. In order to identify new therapeutic targets in aggressive tumors, we sequenced RNA transcripts in five snap frozen retinoblastomas which invaded the optic nerve and five which did not. A three-fold increase was noted in mRNA levels of ACVR1C/ALK7, a type I receptor of the TGF-β family, in invasive retinoblastomas, while downregulation of DACT2 and LEFTY2, negative modulators of the ACVR1C signaling, was observed in most invasive tumors. A two- to three-fold increase in ACVR1C mRNA was also found in invasive WERI Rb1 and Y79 cells as compared to non-invasive cells in vitro. Transcripts of ACVR1C receptor and its ligands (Nodal, Activin A/B, and GDF3) were expressed in six retinoblastoma lines, and evidence of downstream SMAD2 signaling was present in all these lines. Pharmacological inhibition of ACVR1C signaling using SB505124, or genetic downregulation of the receptor using shRNA potently suppressed invasion, growth, survival, and reduced the protein levels of the mesenchymal markers ZEB1 and Snail. The inhibitory effects on invasion, growth, and proliferation were recapitulated by knocking down SMAD2, but not SMAD3. Finally, in an orthotopic zebrafish model of retinoblastoma, a 55% decrease in tumor spread was noted (p=0.0026) when larvae were treated with 3 μM of SB505124, as compared to DMSO. Similarly, knockdown of ACVR1C in injected tumor cells using shRNA also resulted in a 54% reduction in tumor dissemination in the zebrafish eye as compared to scrambled shRNA control (p=0.0005). Our data support a role for the ACVR1C/SMAD2 pathway in promoting invasion and growth of retinoblastoma.
Keratoconus is a highly prevalent (1 in 2000), genetically complex and multifactorial, degenerative disease of the cornea whose pathogenesis and underlying transcriptomic changes are poorly understood. To identify disease-specific changes and gene expression networks, we performed next generation RNA sequencing from individual corneas of two distinct patient populations-one from the Middle East, as keratoconus is particularly severe in this group, and the second from an African American population in the United States. We conducted a case: control RNA sequencing study of 7 African American, 12 Middle Eastern subjects, and 7 controls. A Principal Component Analysis of all expressed genes was used to ascertain differences between samples. Differentially expressed genes were identified using Cuffdiff and DESeq2 analyses, and identification of over-represented signaling pathways by Ingenuity Pathway Analysis. Although separated by geography and ancestry, key commonalities in the two patient transcriptomes speak of disease-intrinsic gene expression networks. We identified an overwhelming decrease in the expression of anti-oxidant genes regulated by NRF2 and those of the acute phase and tissue injury response pathways, in both patient groups. Concordantly, NRF2 immunofluorescence staining was decreased in patient corneas, while KEAP1, which helps to degrade NRF2, was increased. Diminished NRF2 signaling raises the possibility of NRF2 activators as future treatment strategies in keratoconus. The African American patient group showed increases in extracellular matrix transcripts that may be due to underlying profibrogenic changes in this group. Transcripts increased across all patient samples include Thrombospondin 2 (THBS2), encoding a matricellular protein, and cellular proteins, GAS1, CASR and OTOP2, and are promising biomarker candidates. Our approach of analyzing transcriptomic data from different populations and patient groups will help to develop signatures and biomarkers for keratoconus subtypes. Further, RNA sequence data on individual patients obtained from multiple studies may lead to a core keratoconus signature of deregulated genes and a better understanding of its pathogenesis. Keratoconus (KCN) is a condition where the cornea develops bilateral ectasia, becomes progressively thin and protrudes conically. The patient develops astigmatism, myopia, corneal scarring, with eventual loss of vision 1-5. The major form of keratoconus is asyndromic, where the cornea alone is affected. However, syndromic types of KCN also exist, and are associated with Down, Leber congenital amaurosis, Turner, Marfan and Ehlers-Danlos syndromes 6. Isolated KCN affects individuals in adolescence with an incidence and prevalence of 13.3/100,000
Our series information indicated a different distribution of benign and malignant epithelial lesions with a slightly higher rate of malignancy. BMT was the commonest benign tumor where recurrence was a squeal of incomplete surgical excision. ACC was the commonest malignant tumor with shorter duration of symptoms and radiologic evidence of invasiveness that correlated with the histopathologic features.
Purpose Myeloid sarcoma (MS) of the orbit is an uncommon condition in occurring in children, generally coupled to myeloproliferative neoplasms. Observations We describe two rare cases of orbital MS in young boys with aggressive local symptoms but without evidence of acute myeloid leukemia (AML), both patients underwent orbitotomy for gross-tumor resection and biopsy. At follow up, there was no evidence of recurrence nor evolution of the myeloproliferative neoplasms clinically and by radiological and laboratory work-up. We also provide a detailed description of the magnetic resonance imaging presentation, with an extensive pathological analysis correlation. Conclusions and importance A comprehensive revision of the literature on isolated orbital MS was carried out with particular emphasis on clues for differential diagnosis and treatment options, stressing the need to consider MS even in the absence of sign and symptoms of an underlying myeloproliferative disorders.
IMPORTANCE Although a variety of well-characterized diseases, such as sarcoidosis and granulomatosis with polyangiitis, affect the lacrimal gland, many patients with dacryoadenitis are diagnosed as having nonspecific orbital inflammation (NSOI) on the basis of histology and systemic disease evaluation. The ability to further classify the disease in these patients should facilitate selection of effective therapies.OBJECTIVE To test the a priori hypothesis that gene expression profiles would complement clinical and histopathologic evaluations in identifying well-characterized diseases and in subdividing NSOI into clinically relevant groups. DESIGN, SETTING, AND PARTICIPANTSIn this cohort study, gene expression levels in biopsy specimens of inflamed and control lacrimal glands were measured with microarrays. Stained sections of the same biopsy specimens were used for evaluation of histopathology. Tissue samples of patients were obtained from oculoplastic surgeons at 7 international centers representing 4 countries (United States,
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