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Uveal melanoma (UM) is the most frequent primary ocular malignancy of adults; it exhibits an almost invariably poor prognosis with onset of liver metastases within 10–15 years after the diagnosis. Serine and arginine-rich splicing factor 1 (SRSF1) is an RNA-binding protein with proto-oncogene functions, including stimulation of angiogenesis, cell migration and cell growth; regarding the complex regulation of tumor angiogenesis, it has been suggested that SRSF1 regulates the alternative splicing of vascular endothelial growth factor-α, promoting the formation of its pro-angiogenic isoform. The immunohistochemical expression of SRSF1 on a series of 85 primary UMs, including 39 metastasizing and 46 non-metastasizing cases, was investigated; to clarify the potential pathogenetic role of SRSF1 in this tumor and its effect on angiogenesis, we correlated our immunohistochemical findings with the clinico-pathological features, the prognostic data and blood vascular microvessel density (MVD) findings of the cases from our series. Cases with higher immunohistochemical expression of SRSF1 also had higher MVD, higher metastatic potential and shorter metastasis-free survival; conversely, cases with lower SRSF1 immunoexpression showed lower MVD, lower metastatic risk and longer metastasis-free survival times. Our results suggested that SRSF1 has a negative prognostic role and a pro-angiogenic function in UM. [ABSTRACT FROM AUTHOR]

Background: Currently, radiotherapy represents the most widely employed therapeutic option in patients with uveal melanoma. Although the effects of proton beam radiotherapy on uveal melanoma end ocular tissues have been histologically documented, their appearance at MR imaging is still poorly understood. The purpose of our study was to elucidate the magnetic resonance (MR) semiotics of radiotherapy-induced changes to neoplastic tissues and ocular structures in patients with uveal melanoma undergoing secondary enucleation after proton beam radiotherapy. Methods: Nine patients with uveal melanoma who had undergone proton beam radiotherapy, MR imaging, and subsequent secondary enucleation were retrospectively selected. The histopathologic findings evaluated for irradiated tumors were necrosis, fibrosis, and viable tumor, while the histopathologic findings evaluated for extratumoral ocular/periocular tissues were radiation-related intraocular inflammation, vitreous hemorrhage, optic nerve degeneration, iris neovascularization, and periocular fibrotic adhesions. On MR images, the appearance of the abovementioned histologic features was assessed on conventional and diffusion-weighted sequences. Results: T2-weighted sequences performed better in detecting radiation-induced necrosis, fibrosis, optic nerve degeneration, and periocular fibrotic adhesions. T1-weighted sequences were preferable for identifying cataracts, vitreous hemorrhage, and inflammatory complications. Contrast-enhanced T1-weighted sequences were irreplaceable in assessing iris neovascularization, and in confirming inflammatory complications. Conclusions: In the light of their increasing role in the multidisciplinary management of patients with uveal melanoma, radiologists should be aware of the MR appearance of the effects of radiotherapy on neoplastic and ocular tissue, in order to improve the accuracy of follow-up MR examinations. [ABSTRACT FROM AUTHOR]

The human Wilms' tumor gene (WT1) was originally isolated in a Wilms' tumor of the kidney as a tumor suppressor gene. Numerous isoforms of WT1, by combination of alternative translational start sites, alternative RNA splicing and RNA editing, have been well documented. During human ontogenesis, according to the antibodies used, anti-C or N-terminus WT1 protein, nuclear expression can be frequently obtained in numerous tissues, including metanephric and mesonephric glomeruli, and mesothelial and sub-mesothelial cells, while cytoplasmic staining is usually found in developing smooth and skeletal cells, myocardium, glial cells, neuroblasts, adrenal cortical cells and the endothelial cells of blood vessels. WT1 has been originally described as a tumor suppressor gene in renal Wilms' tumor, but more recent studies emphasized its potential oncogenic role in several neoplasia with a variable immunostaining pattern that can be exclusively nuclear, cytoplasmic or both, according to the antibodies used (anti-C or N-terminus WT1 protein). With the present review we focus on the immunohistochemical expression of WT1 in some tumors, emphasizing its potential diagnostic role and usefulness in differential diagnosis. In addition, we analyze the WT1 protein expression profile in human embryonal/fetal tissues in order to suggest a possible role in the development of organs and tissues and to establish whether expression in some tumors replicates that observed during the development of tissues from which these tumors arise. [ABSTRACT FROM AUTHOR]

Congenital anomalies of the kidney and urinary tract (CAKUT) include isolated kidney malformations and urinary tract malformations. They have also been reported in Prune-Belly syndrome (PBS) and associated genetic syndromes, mainly 13, 18 and 21 trisomy. The AA focuses on bladder and urethral malformations, evaluating the structural and histological differences between two different cases of megacystis. Both bladders were examined by routine prenatal ultrasound screening and immunohistochemistry, comparing the different expression of smooth muscular actin (SMA), S100 protein and WT1c in megacystis and bladders of normal control from fetuses of XXI gestational age. Considering the relationship between the enteric nervous system and urinary tract development, the AA evaluated S100 and WT1c expression both in bladder and bowel muscular layers. Both markers were not expressed in the bladder and bowel of PBS associated with anencephaly. In conclusion, megacystis could be considered only a macroscopic definition, concerning the size of the fetal bladder rather than the embryologic origin; it may be a single or multiple malformation; the possible association with the bowel and/or encephalic malformations will decide the outcome and prognosis in fetal megacystis. [ABSTRACT FROM AUTHOR]

MacroH2A is a histone variant whose expression has been studied in several neoplasms, including cutaneous melanomas (CMs). In the literature, it has been demonstrated that macroH2A.1 levels gradually decrease during CM progression, and a high expression of macroH2A.1 in CM cells relates to a better prognosis. Although both uveal and cutaneous melanomas arise from melanocytes, uveal melanoma (UM) is biologically and genetically distinct from the more common cutaneous melanoma. Metastasis to the liver is a frequent occurrence in UM, and about 40%–50% of patients die of metastatic disease, even with early diagnosis, proper treatment, and close follow-up. We wanted to investigate macroH2A.1 immunohistochemical expression in UM. Our results demonstrated that mH2A.1 expression was higher in metastatic UM (21/23, 91.4%), while only 18/32 (56.3%). UMs without metastases showed mH2A.1 staining. These data could suggest a possible prognostic role for mH2A.1 and could form a basis for developing new pharmacological strategies for UM treatment. [ABSTRACT FROM AUTHOR]

Uveal melanoma represents the most common primary intraocular malignancy in adults; it may arise in any part of the uveal tract, with choroid and ciliary bodies being the most frequent sites of disease. In the present paper we studied ABCB5 expression levels in patients affected by uveal melanoma, both with and without metastasis, in order to evaluate if ABCB5 is associated with a higher risk of metastatic disease and can be used as a poor prognostic factor in uveal melanoma. The target population consisted of 23 patients affected by uveal melanoma with metastasis and 32 without metastatic disease. A high expression of ABCB5 was seen in patients with metastasis (14/23, 60.9%), compared to that observed in patients without metastasis (13/32, 40.6%). In conclusion, we found that ABCB5 expression levels were correlated with faster metastatic progression and poorer prognosis, indicating their role as a prognostic factor in uveal melanoma. [ABSTRACT FROM AUTHOR]