A dominant-negative SOX18 mutant disrupts multiple regulatory layers essential to transcription factor activity.

Few genetically dominant mutations involved in human disease have been fully explained at the molecular level. In cases where the mutant gene encodes a transcription factor, the dominant-negative mode of action of the mutant protein is particularly poorly understood. Here, we studied the genome-wide mechanism underlying a dominant-negative form of the SOX18 transcription factor (SOX18RaOp) responsible for both the classical mouse mutant Ragged Opossum and the human genetic disorder Hypotrichosis-lymphedema-telangiectasia-renal defect syndrome. Combining three single-molecule imaging assays in living cells together with genomics and proteomics analysis, we found that SOX18RaOp disrupts the system through an accumulation of molecular interferences which impair several functional properties of the wild-type SOX18 protein, including its target gene selection process. The dominant-negative effect is further amplified by poisoning the interactome of its wild-type counterpart, which perturbs regulatory nodes such as SOX7 and MEF2C. Our findings explain in unprecedented detail the multi-layered process that underpins the molecular aetiology of dominant-negative transcription factor function.

The association of photo-induced collagen degeneration and the development of telangiectasias in rosacea.

Rosacea is a chronic, often progressive disorder characterized by facial erythema, telangiectasias, papules, pustules, and/or rhinophyma. In this study, we investigated the tissue structure in rosacea compared to controls. We performed a case-control study between five patients with mild-to-moderate erythematotelangiectatic rosacea (ETR) and five matched controls. Facial biopsy samples from rosacea patients and controls were stained with picrosirius red for collagen and CD31 for microvessel identification. Mean collagen content was significantly greater in control samples (19.603% ±8.821%) compared to rosacea samples (16.812% ± 7.787%, p = 0.030). In contrast, mean microvessel density was significantly higher in rosacea patients (4.775 E-5 ± 1.493 E-5 µm-3 ) compared to controls (2.559 E-5 ± 8.732 E-6 µm-3 , p = 0.004). Mean microvessel lumen area was also significantly higher in rosacea patients (491.710 ± 610.188 µm2 ) compared to controls (347.879 ± 539.624 µm2 , p = 0.003). We identified a correlation between decreased collagen content and increased microvessel size and density in rosacea patients that was not observed in controls. These structural changes to the dermal matrix may contribute to the characteristic vessel growth and dilation in rosacea.

Metabolic Phenotyping in Venous Disease: The Need for Standardization.

Venous thromboembolism (VTE), chronic venous disease (CVD), and venous leg ulceration (VLU) are clinical manifestations of a poorly functioning venous system. Though common, much is unknown of the pathophysiology and progression of these conditions. Metabolic phenotyping has been employed to explore mechanistic pathways involved in venous disease. A systematic literature review was performed: full text, primary research articles on the applications of nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) in human participants and animals were included for qualitative synthesis. Seventeen studies applying metabolic phenotyping to venous disease were identified: six on CVD, two on VLU, and nine on VTE; both animal (n = 6) and human (n = 10) experimental designs were reported, with one study including both. NMR, MS, and MS imaging were employed to characterize serum, plasma, urine, wound fluid, and tissue. Metabolites found to be upregulated in CVD included lipids, branched chain amino acids (BCAA), glutamate, taurine, lactate, and myo-inositol identified in vein tissue. Upregulated metabolites in VLU included lactate, BCAA, lysine, 3-hydroxybutyrate, and glutamate identified in wound fluid and ulcer biopsies. VTE cases were associated with reduced carnitine levels, upregulated aromatic amino acids, 3-hydroxybutyrate, BCAA, and lipids in plasma, serum, thrombus, and vein wall; kynurenine and tricarboxylic acid pathway dysfunction were reported. Future research should focus on targeted studies with internal and external validation.

Understanding the evolving phenotype of vascular complications in telomere biology disorders.

Vascular complications such as bleeding due to gastrointestinal telangiectatic anomalies, pulmonary arteriovenous malformations, hepatopulmonary syndrome, and retinal vessel abnormalities are being reported in patients with telomere biology disorders (TBDs) more frequently than previously described. The international clinical care consortium of telomere-associated ailments and family support group Dyskeratosis Congenita Outreach, Inc. held a workshop on vascular abnormalities in the TBDs at the National Cancer Institute in October 2017. Clinicians and basic scientists reviewed current data on vascular complications, hypotheses for the underlying biology and developed new collaborations to address the etiology and clinical management of vascular complications in TBDs.

Linoleic acid content of human meibum is associated with telangiectasia and plugging of gland orifices in meibomian gland dysfunction.

To examine the relation between changes in the free fatty acid (FFA) composition of human meibum and both objective signs and subjective symptoms of meibomian gland dysfunction (MGD), we analyzed the FFA content of meibum collected from both MGD patients and control subjects. Thirty-eight patients with MGD (13 men and 25 women; mean age ± SD, 66.9 ± 15.0 years) were evaluated. Various objective signs and subjective symptoms of MGD were assessed. Meibum was analyzed by liquid chromatography-Fourier transform mass spectrometry, and the relation between the FFA composition of meibum and each objective sign and subjective symptom was examined by principal component analysis (PCA). No relation was apparent between the FFA composition of meibum and individual subjective symptoms or objective signs of MGD. However, a PCA score plot for meibum samples grouped on the basis of the severity of both telangiectasia and plugging of meibomian gland orifices revealed clear separation of mild and severe groups. This separation of the two groups was largely due to a significantly increased linoleic acid content in meibum of the severe group (3.56%, versus 0.70% of total FFAs in the mild group). The relative amount of linoleic acid in meibum was thus associated with the severity of telangiectasia and plugging of gland orifices in MGD, suggesting that this FFA might contribute to the pathogenesis of these signs.

Aortic Dilatation Associated With a De Novo Mutation in the SOX18 Gene: Expanding the Clinical Spectrum of Hypotrichosis-Lymphedema-Telangiectasia Syndrome.

BACKGROUND: We report a 13-year-old female patient followed since birth for multiple rare congenital defects, including hypotrichosis, telangiectasia, and severe dilatation of the ascending aorta. METHODS: Comprehensive phenotype assessment throughout childhood included repeated echocardiographic measurements, evaluation of renal function, and immunohistochemical analysis of skin biopsy samples. Whole-exome sequencing was performed for the patient and both unaffected parents. RESULTS: We identified a novel de novo mutation in the transcription factor SOX18 (c.481C>T:p.Gln161*) in the patient, which was absent in all unaffected family members. Echocardiography revealed early onset and progressive dilatation of the ascending aorta. Skin biopsy results confirmed the defects of the blood vasculature in the presence of intact lymphatic vessels. Assessment of renal function did not show any signs of renal problems or renal failure in the patient. CONCLUSIONS: The genetic finding of a pathogenic SOX18 mutation enabled the diagnosis of the rare hypotrichosis-lymphedema-telangiectasia syndrome in our patient. The identification of a novel stop gain mutation in the SOX18 gene in association with dilatation of the aorta highlights the importance of this gene during the development of the circulatory system. Our study highlights the importance of whole-exome sequencing in the rapid identification of genes and gene mutations involved in rare conditions and thus expanding the knowledge and spectrum of clinical manifestations associated with them.

Apoptosis for prediction of radiotherapy late toxicity: lymphocyte subset sensitivity and potential effect of TP53 Arg72Pro polymorphism.

We tested apoptosis levels in in vitro irradiated T-lymphocytes from breast cancer (BC) patients with radiotherapy-induced late effects. Previous results reported in the literature were revised. We also examined the effect of TP53 Arg72Pro polymorphism on irradiation-induced apoptosis (IA). Twenty BC patients, ten with fibrosis and/or telangiectasias and ten matched controls with no late reactions, were selected from those receiving radiotherapy between 1993 and 2007. All patients were followed-up at least 6 years after radiotherapy. Using the combination of both CD3 and CD8 antibodies the in vitro IA was measured in CD3, CD8 and CD4 T-lymphocytes, and CD8 natural killer lymphocytes (CD8 NK) by flow cytometry. The TP53 Arg72Pro genotype was determined by sequencing. Patients with late radiotherapy toxicity showed less IA for all T-lymphocytes except for the CD8 NK. CD8 NK showed the highest spontaneous apoptosis and the lowest IA. IA in patients with toxicity appears to be lower than the control patients only in TP53 Arg/Arg patients (P = 0.077). This difference was not present in patients carrying at least one Pro allele (P = 0.8266). Our data indicate that late side effects induced by radiotherapy of BC are associated to low levels of IA. CD8 NK cells have a different response to in vitro irradiation compared to CD8 T-lymphocytes. It would be advisable to distinguish the CD8 NK lymphocytes from the pool of CD8+ lymphocytes in IA assays using CD8+ cells. Our data suggest that the 72Pro TP53 allele may influence the IA of patients with radiotherapy toxicity.

Telangiectatic hyperplastic nodule associated with vascular malformation in a patient with chronic hepatitis B: radiologic and pathologic features.

Recognizing hepatocellular nodules that cannot be classified as typical for hepatocellular carcinoma, hepatocellular adenoma, or focal nodular hyperplasia is important, especially in a patient with high risk for hepatocellular carcinoma. The authors report a case of a 53-year-old man with chronic hepatitis B, who was referred to the hospital with a liver mass found on routine imaging follow-up. Abdominal ultrasound revealed a 2.4-cm hypoechoic lesion. Contrast computed tomography showed homogeneous arterial enhancement and mild hyperdensity on portal venous phase images. Due to the high risk for hepatocellular carcinoma, the patient underwent laparoscopic left lateral segmentectomy that revealed a 2.2-cm poorly defined red-brown lesion. The nodule was diagnosed as a hypervascular/telangiectatic hyperplastic hepatocellular nodule based on histopathologic findings and immunostaining profile with negative glutamine synthetase, diffuse positive CD34 highlighting hyperplastic endothelial cells along the telangiectatic sinusoids and dilated vascular channels, and CK7 and CK19 reactive normal bile ducts within the lesion.

Mammosphere cells from high-passage MCF7 cell line show variable loss of tumorigenicity and radioresistance.

Mammosphere culture of cancer cell lines is an important approach used for enrichment of stem-like cancer cells (SLCs), but over-subcultured cell lines have been experimentally shown to change properties over time. It remains unclear if mammosphere cells (MSs) derived from high-passage cancer cell lines retain the tumorigenicity and radioresistance seen in MSs from primary or low-passage cell lines. In this study, we report that mammospheres derived from MCF-7 sublines after different passage numbers were consistently enriched for CD44+/CD24(-/low) cells but were not consistently enriched for tumorigenic and radioresistant cells. The tumorigenicity and radioresistance of MSs were associated with their sphere-forming ability, proliferation ability in vitro, and intracellular reactive oxygen species (ROS) levels. The radioresistant MSs showed significant cell cycle arrest in G2/M phase after X-ray irradiation and expressed higher ataxia telangiectasia mutated (ATM) mRNA levels. These results suggest that MSs from high-passage cancer cell lines were not consistently enriched for stem-like cancer cells with higher tumorigenicity and enhanced radioresistance.

Lack of significant estrogen and progesterone receptor expression in nasal telangiectasias in hereditary hemorrhagic telangiectasia: an immunohistochemical analysis.

CONCLUSION: This immunohistochemical study of estrogen and progesterone receptors could not confirm a significant expression in nasal telangiectasias. Thus, a specific effect of these hormones or anti-hormone therapy on malformed nasal vessels has to be questioned and only offered under strict clinical control. OBJECTIVE: The efforts to control recurrent epistaxis in hereditary hemorrhagic telangiectasia (HHT) using alternative methods are very intense. Hormone or anti-hormone therapy has frequently been postulated and the reported results are controversial. Therefore it was important to find an explanation regarding a possible impact of hormonal therapies by immunohistochemical evaluation of progesterone and estrogen receptor expression on nasal telangiectasias of affected patients. METHODS: Tissue samples of nasal mucosa with evidence of telangiectasias from 14 patients with HHT were analyzed for the expression of progesterone and estrogen receptors on the nuclei of endothelial cells of the malformed vessels using immunohistochemistry. RESULTS: Progesterone receptors were not detected in any of the cases and only two cases showed a weak expression of estrogen receptors with an immunoreactive score of 2/12.

Unilateral nevoid telangiectasia syndrome: a case report and review of the literature.

We report on a 43-year-old Caucasian female who presented with bright red macules in a unilateral distribution in the left C5-8 and L3-5 dermatomes. Histopathologic examination showed superficial papillary dermal telangiectasia with minimal chronic inflammation. Immunohistochemical stains for estrogen and progesterone receptors (ER/PR) were negative. A diagnosis of unilateral nevoid telangiectasia syndrome (UNTS) was given. UNTS is an uncommon disorder first described by Alfred Blaschko in 1899. It is comprised of telangiectasias occurring in a predominantly unilateral dermatomal distribution and often affecting the trigeminal, cervical, and upper thoracic dermatomes. It can be either congenital or acquired and has a 2:1 female:male ratio. UNTS has been reported in relation to hyperestrogenic states, with half of the reported cases related to pregnancy, puberty, or liver disease. However, the vast majority of cases show no increase in estrogen and progesterone receptors in lesional skin. UNTS may be more common than previously believed, and shows some response to vascular laser therapy. Differential diagnoses include hemangioma, angioma serpiginosum, and rarely, nevus flammeus.

Hepatocellular carcinoma arising in a pigmented telangiectatic adenoma with nuclear ß-catenin and glutamine synthetase positivity: case report and review of the literature.

Telangiectatic hepatocellular adenoma is a rare, recently recognized subtype of hepatocellular adenoma that is often underrecognized by pathologists. We report a case of hepatocellular carcinoma arising within a pigmented telangiectatic hepatocellular adenoma in a noncirrhotic man with diffuse glutamine synthetase and nuclear ß-catenin positivity. This case highlights malignant transformation of telangiectatic adenomas, and describes a previously unreported association between pigment deposition and telangiectatic adenoma. Radiology, gross pathology, and histopathology are shown. Review of the literature with attention to ß-catenin and glutamine synthetase staining, malignant transformation, patient characteristics, the presence of Dubin-Johnson-like pigment, and genetic characteristics of telangiectatic adenomas are discussed.

The continuum of primary retinal telangiectasia.

BACKGROUND: Primary retinal telangiectasia is characterized by abnormalities in the retinal vasculature. Any alteration of the normal retinal vasculature may result in variable degrees of retinal leakage, hemorrhages, and exudates. The retinal telangiectatic conditions of Coats' disease, Leber's miliary aneurysms, and idiopathic macular telangiectasia (IMT), although historically considered separate entities, may in fact be variants of the same pathophysiologic vascular process. This is based on observations noting that they share similarities in pathogenesis, histology, and clinical presentation. These observations are controversial and are contested in the literature. Conversely, others have documented Coats' disease, Leber's miliary aneurysms, and IMT as unique and separate retinal conditions, each with specific features. METHODS: Three cases are presented spanning the spectrum of primary retinal telangiectasia. Clinical evaluation, dilated fundus examination, and auxiliary testing document both the similar characteristics that the entities share as well as the distinct features, which define each disease's nomenclature and categorization. CONCLUSION: Coats' disease, Leber's miliary aneurysms, and IMT may be part of a singular clinical spectrum sharing pathophysiologic and histopathologic features and similarities in clinical presentation.

Macular telangiectasia: patterns of distribution of macular pigment and response to supplementation.

PURPOSE: By analyzing the patterns of macular pigment (MP) in type 2 idiopathic telangiectasia eyes, different stages in the changes reflecting the extent of disease can be observed. The purpose of this study was to determine whether the amount and the pattern of MP can be influenced by supplementation. METHOD: Eleven patients with type 2 idiopathic telangiectasia received 12 mg lutein and 0.6 mg zeaxanthin (Ocuvite Lutein AMD) daily for 9 months. For a period of 12 months, MP concentration was determined every 3 months by autofluorescence (2 excitation wavelengths: 488 and 514 nm). RESULTS: When central accumulation of MP was similar to that in healthy subjects (with segment of reduced MP in the temporal fovea: MP Class I), supplementation enriched the MP at 0.5 degrees, 2 degrees, and 5 degrees to 6 degrees. In MP Class II (reduced concentration of MP centrally), accumulation could be detected at 2 degrees and 5 degrees to 6 degrees but not centrally. In MP Class III (oval-shaped effacement of MP centrally, surrounding oval-shaped ring of MP at 5 degrees-7 degrees eccentricity), supplementation promoted MP accumulation only at 5 degrees to 6 degrees. CONCLUSION: After oral supplementation with lutein/zeaxanthin, an increase in the MP was detected only in areas where the MP was present at baseline. Supplementation did not produce an increase in the area where the MP was absent. Degenerative processes causing an impairment in transport and storage of lutein and zeaxanthin may play a leading role in the pathogenesis of type 2 idiopathic telangiectasia.

Elevated vascular endothelial growth factor level in Coats' disease and possible therapeutic role of bevacizumab.

PURPOSE: To compare intraocular vascular endothelial growth factor (VEGF) level in patients with and without Coats' disease, and to report a case of Coats' disease that responded to intravitreal injection of bevacizumab. METHODS: Intraocular fluid was obtained from four eyes with Coats' disease (subretinal fluid in three eyes and aqueous in one eye) and from five eyes with rhegmatogenous retinal detachment (subretinal fluid in four eyes and vitreous in one eye). Intraocular VEGF level was compared between these two groups. In one eye with stage 2B Coats' disease, macular edema, visual acuity, and intraocular VEGF level were compared before and after intravitreal injection of bevacizumab. RESULTS: Mean intraocular VEGF level in eyes with Coats' disease was 2,394.5 pg/ml, compared to 15.3 pg/ml in eyes with rhegmagenous retinal detachment. In the eye with stage 2B Coats' disease, macular edema was reduced after bevacizumab injection, and the visual acuity improved from 0.05 to 0.2. Intraocular VEGF level decreased from 1247 pg/ml to 20.4 pg/ml 1 month after the injection. CONCLUSION: Coats' disease is associated with increased intraocular VEGF level. Bevacizumab may be a valuable adjunctive treatment for Coats' disease.