sFRP2 in the aged microenvironment drives melanoma metastasis and therapy resistance.

Cancer is a disease of ageing. Clinically, aged cancer patients tend to have a poorer prognosis than young. This may be due to accumulated cellular damage, decreases in adaptive immunity, and chronic inflammation. However, the effects of the aged microenvironment on tumour progression have been largely unexplored. Since dermal fibroblasts can have profound impacts on melanoma progression, we examined whether age-related changes in dermal fibroblasts could drive melanoma metastasis and response to targeted therapy. Here we find that aged fibroblasts secrete a Wnt antagonist, sFRP2, which activates a multi-step signalling cascade in melanoma cells that results in a decrease in ß-catenin and microphthalmia-associated transcription factor (MITF), and ultimately the loss of a key redox effector, APE1. Loss of APE1 attenuates the response of melanoma cells to DNA damage induced by reactive oxygen species, rendering the cells more resistant to targeted therapy (vemurafenib). Age-related increases in sFRP2 also augment both angiogenesis and metastasis of melanoma cells. These data provide an integrated view of how fibroblasts in the aged microenvironment contribute to tumour progression, offering new possibilities for the design of therapy for the elderly.

Bi-allelic Alterations in AEBP1 Lead to Defective Collagen Assembly and Connective Tissue Structure Resulting in a Variant of Ehlers-Danlos Syndrome.

AEBP1 encodes the aortic carboxypeptidase-like protein (ACLP) that associates with collagens in the extracellular matrix (ECM) and has several roles in development, tissue repair, and fibrosis. ACLP is expressed in bone, the vasculature, and dermal tissues and is involved in fibroblast proliferation and mesenchymal stem cell differentiation into collagen-producing cells. Aebp1-/- mice have abnormal, delayed wound repair correlating with defects in fibroblast proliferation. In this study, we describe four individuals from three unrelated families that presented with a unique constellation of clinical findings including joint laxity, redundant and hyperextensible skin, poor wound healing with abnormal scarring, osteoporosis, and other features reminiscent of Ehlers-Danlos syndrome (EDS). Analysis of skin biopsies revealed decreased dermal collagen with abnormal collagen fibrils that were ragged in appearance. Exome sequencing revealed compound heterozygous variants in AEBP1 (c.1470delC [p.Asn490_Met495delins(40)] and c.1743C>A [p.Cys581∗]) in the first individual, a homozygous variant (c.1320_1326del [p.Arg440Serfs∗3]) in the second individual, and a homozygous splice site variant (c.1630+1G>A) in two siblings from the third family. We show that ACLP enhances collagen polymerization and binds to several fibrillar collagens via its discoidin domain. These studies support the conclusion that bi-allelic pathogenic variants in AEBP1 are the cause of this autosomal-recessive EDS subtype.

Spontaneous pneumothorax and hemothorax frequently precede the arterial and intestinal complications of vascular Ehlers-Danlos syndrome.

Vascular Ehlers-Danlos syndrome (vEDS) is a connective tissue disorder due to defective type III collagen production and is associated with arterial rupture, spontaneous intestinal perforation, and gravid uterine rupture. Spontaneous pneumothorax and/or hemothorax (P/HTX) also occurs in vEDS patients. The temporal relation of pulmonary manifestations to arterial and intestinal complications in vEDS has not been well described. This was investigated in a multi-institutional retrospective case series of vEDS patients with confirmatory testing for COL3A1 mutation between 2000 and 2012. Data abstracted included demographics, family histories, presentation, and management of associated complications. Ninety-six cases (39% males, mean age 38.6 ± 15.5 years, range 8-79) had confirmatory testing for vEDS. P/HTX was documented in 17 (17.7%) cases. Most P/HTX preceded the diagnosis of vEDS (81%). Diagnosis of vEDS was made after arterial or intestinal complications at a mean of 7 years (range 0-26) post the initial P/HTX. In conclusion, spontaneous P/HTX is an early manifestation of vEDS frequently preceding an arterial complication or intestinal perforation. Thus, a spontaneous P/HTX in a young patient should trigger a differential diagnosis that includes vEDS. This should lead to an investigation of other vEDS features and subsequent genetic testing if vEDS features are present.

Heritable disorders of connective tissue: Description of a data repository and initial cohort characterization.

We describe a data repository on heritable disorders of connective tissue (HDCT) assembled by the National Institutes of Health's National Institute on Aging (NIA) Intramural Research Program between 2001 and 2013. Participants included affected persons with a wide range of heritable connective tissue phenotypes, and unaffected family members. Elements include comprehensive history and physical examination, standardized laboratory data, physiologic measures and imaging, standardized patient-reported outcome measures, and an extensive linked biorepository. The NIA made a commitment to make the repository available to extramural investigators and deposited samples at Coriell Tissue Repository (N = 126) and GenTAC registry (N = 132). The clinical dataset was transferred to Penn State University College of Medicine Clinical and Translational Science Institute in 2016, and data elements inventoried. The consented cohort of 1,009 participants averaged 39 ± 18 years (mean ± SD, range 2-95) at consent; gender distribution is 71% F and 83% self-report Caucasian ethnicity. Diagnostic categories include Ehlers-Danlos syndrome (classical N = 50, hypermobile N = 99, vascular N = 101, rare types and unclassified N = 178), Marfan syndrome (N = 33), Stickler syndrome (N = 60), fibromuscular dysplasia (N = 135), Other HDCT (N = 72). Unaffected family members (N = 218) contributed DNA for the molecular archive only. We aim to develop further discrete data from unstructured elements, analyze multisymptom HDCT manifestations, encourage data use by other researchers and thereby better understand the complexity of these high-morbidity conditions and their multifaceted effects on affected persons.

Clinical and biochemical profiles suggest fibromuscular dysplasia is a systemic disease with altered TGF-ß expression and connective tissue features.

Fibromuscular dysplasia (FMD) is a rare, nonatherosclerotic arterial disease for which the molecular basis is unknown. We comprehensively studied 47 subjects with FMD, including physical examination, spine magnetic resonance imaging, bone densitometry, and brain magnetic resonance angiography. Inflammatory biomarkers in plasma and transforming growth factor ß (TGF-ß) cytokines in patient-derived dermal fibroblasts were measured by ELISA. Arterial pathology other than medial fibrodysplasia with multifocal stenosis included cerebral aneurysm, found in 12.8% of subjects. Extra-arterial pathology included low bone density (P<0.001); early onset degenerative spine disease (95.7%); increased incidence of Chiari I malformation (6.4%) and dural ectasia (42.6%); and physical examination findings of a mild connective tissue dysplasia (95.7%). Screening for mutations causing known genetically mediated arteriopathies was unrevealing. We found elevated plasma TGF-ß1 (P=0.009), TGF-ß2 (P=0.004) and additional inflammatory markers, and increased TGF-ß1 (P=0.0009) and TGF-ß2 (P=0.0001) secretion in dermal fibroblast cell lines from subjects with FMD compared to age- and gender-matched controls. Detailed phenotyping of patients with FMD allowed us to demonstrate that FMD is a systemic disease with alterations in common with the spectrum of genetic syndromes that involve altered TGF-ß signaling and offers TGF-ß as a marker of FMD.

Molecular diagnosis in vascular Ehlers-Danlos syndrome predicts pattern of arterial involvement and outcomes.

OBJECTIVE: The management of arterial pathology in individuals with vascular Ehlers-Danlos syndrome (vEDS) remains a challenge. Here we describe the correlation between COL3A1 gene mutation type and the clinical phenotype in individuals with vEDS. METHODS: Individuals with confirmed molecular diagnoses of vEDS were enrolled in a multi-institutional natural history study. Data collected included demographics, clinical and family histories, arterial pathology (aneurysm, dissection, and rupture), operative details, and autopsy reports. Individuals were classified into two cohorts by the type of COL3A1 mutations and their effect on the amount of normal collagen produced: those with mutations that lead to minimal (MIN) production (10%-15%) of normal type III collagen and those with haploinsufficiency (HI) mutations that lead to production of 50% of the normal type III collagen. RESULTS: A cohort of 68 individuals (72%) from 56 families had arterial pathology (44% male) with 13% HI. The HI group was older at the time of their first vascular event (mean, 42 [range, 26-58] years vs 33 [range, 8-62] years; P = .016) and had a higher incidence of aortic pathology than the MIN group (56% vs 21%; P = .025). Visceral arterial pathology was seen in 43 arteries in 23 individuals in the MIN group vs only one artery in five individuals in the HI group. Emergency surgical procedures were more likely to be undertaken when vEDS diagnosis was not known (81% vs 41%; P = .005), and 81% of these procedures were open surgical repair compared with 19% endovascular repairs (P = .019). Open and endovascular repairs were equally used in the elective setting. Postoperative complications were highest when the diagnosis of vEDS was not known (62% vs 14%; P < .001) and when procedures were undertaken in an emergency setting (5% vs 55% P < .001). Mortality due to arterial complications was 0% in the HI cohort and 21% in the MIN cohort (P = .132). CONCLUSIONS: Arterial pathology in vEDS individuals is related to the underlying COL3A1 mutation type. The arterial pathology in individuals with HI mutations occurs at later ages with a higher incidence of aortic disease compared with other COL3A1 mutation types. Molecular diagnosis is recommended because diagnosis confirmation, appropriate surveillance, and prophylactic interventions in an elective setting improve surgical outcomes.

Allele-specific siRNA knockdown as a personalized treatment strategy for vascular Ehlers-Danlos syndrome in human fibroblasts.

The vascular type of the Ehlers-Danlos syndrome (vEDS) is caused by dominant-negative mutations in the procollagen type III (COL3A1) gene. Patients with this autosomal dominant disorder have a shortened life expectancy due to complications from ruptured vessels or hollow organs. We tested the effectiveness of allele-specific RNA interference (RNAi) to reduce the mutated phenotype in fibroblasts. Small-interfering RNAs (siRNAs) discriminating between wild-type and mutant COL3A1 allele were identified by a luciferase reporter gene assay and in primary fibroblasts from a normal donor and a patient with vEDS. The best discriminative siRNA with the mutation at position 10 resulted in >90% silencing of the mutant allele without affecting the wild-type allele. Transmission and immunogold electron microscopy of extracted extracellular matrices from untreated fibroblasts of the patient with vEDS revealed structurally abnormal fibrils. After siRNA treatment, collagen fibrils became similar to fibrils from fibroblasts of normal and COL3A1 haploinsufficient donors. In addition, it was shown that expression of mutated COL3A1 activates the unfolded protein response and that reduction of the amount of mutated protein by siRNA reduces cellular stress. Taken together, the results provide evidence that allele-specific siRNAs are able to reduce negative effects of mutated COL3A1 proteins. Thus, the application of allele-specific RNAi may be a promising direction for future personalized therapies to reduce the severity of vEDS.

A mutation in TGFB3 associated with a syndrome of low muscle mass, growth retardation, distal arthrogryposis and clinical features overlapping with Marfan and Loeys-Dietz syndrome.

The transforming growth factor ß (TGF-ß) family of growth factors are key regulators of mammalian development and their dysregulation is implicated in human disease, notably, heritable vasculopathies including Marfan (MFS, OMIM #154700) and Loeys-Dietz syndromes (LDS, OMIM #609192). We described a syndrome presenting at birth with distal arthrogryposis, hypotonia, bifid uvula, a failure of normal post-natal muscle development but no evidence of vascular disease; some of these features overlap with MFS and LDS. A de novo mutation in TGFB3 was identified by exome sequencing. Several lines of evidence indicate the mutation is hypomorphic suggesting that decreased TGF-ß signaling from a loss of TGFB3 activity is likely responsible for the clinical phenotype. This is the first example of a mutation in the coding portion of TGFB3 implicated in a clinical syndrome suggesting TGFB3 is essential for both human palatogenesis and normal muscle growth.

Complement component 4 copy number variation and CYP21A2 genotype associations in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is an autosomal recessive disorder of cortisol biosynthesis caused by CYP21A2 mutations. An increase in gene copy number variation (CNV) exists at the CYP21A2 locus. CNV of C4, a neighboring gene that encodes complement component 4, is associated with autoimmune disease susceptibility. In this study, we performed comprehensive genetic analysis of the RP-C4-CYP21-TNX (RCCX) region in 127 unrelated 21-OHD patients (100 classic, 27 nonclassic). C4 copy number was determined by Southern blot. C4 CNV and serum C4 levels were evaluated in relation to CYP21A2 mutations and relevant phenotypes. We found that the most common CYP21A2 mutation associated with the nonclassic form of CAH, V281L, was associated with high C4 copy number (p = 7.13 × 10(-16)). Large CYP21A2 deletion, a common mutation associated with the classic form of CAH, was associated with low C4 copy number (p = 1.61 × 10(-14)). Monomodular RCCX with a short C4 gene, a risk factor for autoimmune disease, was significantly less frequent in CAH patients compared to population estimates (2.8 vs. 10.6 %; p = 1.08 × 10(-4)). In conclusion, CAH patients have increased C4 CNV, with mutation-specific associations that may be protective for autoimmune disease. The study of CYP21A2 in relation to neighboring genes provides insight into the genetics of CNV hotspots, an important determinant of human health.

Junction site analysis of chimeric CYP21A1P/CYP21A2 genes in 21-hydroxylase deficiency.

BACKGROUND: Chimeric CYP21A1P/CYP21A2 genes, caused by homologous recombination between CYP21A2 (cytochrome P450, family 21, subfamily A, polypeptide 2) and its highly homologous pseudogene CYP21A1P (cytochrome P450, family 21, subfamily A, polypeptide 1 pseudogene), are common in patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD). A comprehensive junction site analysis of chimeric CYP21A1P/CYP21A2 genes is needed for optimizing genetic analysis strategy and determining clinical relevance. METHODS: We conducted a comprehensive genetic analysis of chimeric CYP21A1P/CYP21A2 genes in a cohort of 202 unrelated 21-OHD patients. Targeted CYP21A2 mutation analysis was performed, and genotyping of chimeric CYP21A1P/CYP21A2 genes was cross-confirmed with Southern blot, RFLP, and multiplex ligation-dependent probe amplification analyses. Junction sites of chimera genes were determined by sequencing the long-PCR products amplified with primers CYP779f and Tena32F. An updated bioinformatics survey of Chi-like sequences was also performed. RESULTS: Of 100 probands with a chimeric allele, 96 had a chimera associated with the severe classic salt-wasting form of CAH, and the remaining 4 carried an uncommon attenuated chimera with junction sites upstream of In2G (c.293-13A/C>G), which is associated with a milder phenotype. In addition to 6 of 7 reported chimeras, we identified a novel classic chimera (CH-8) and a novel attenuated chimera (CH-9). Attenuated chimeras explained prior genotype-phenotype discrepancies in 3 of the patients. Sequencing the CYP779f/Tena32F amplicons accurately differentiated between classic and attenuated chimeras. The bioinformatics survey revealed enrichment of Chi-like sequences within or in the vicinity of intron 2. CONCLUSIONS: Junction site analysis can explain some genotype-phenotype discrepancies. Sequencing the well-established CYP779f/Tena32F amplicons is an unequivocal strategy for detecting attenuated chimeric CYP21A1P/CYP21A2 genes, which are clinically relevant.

Doxycycline ameliorates the susceptibility to aortic lesions in a mouse model for the vascular type of Ehlers-Danlos syndrome.

The vascular form of Ehlers-Danlos syndrome (vEDS), a rare disease with grave complications resulting from rupture of major arteries, is caused by mutations of collagen type III [α1 chain of collagen type III (COL3A1)]. The only, recently proven, preventive strategy consists of the reduction of arterial wall stress by ß-adrenergic blockers. The heterozygous (HT) Col3a1 knockout mouse has reduced expression of collagen III and recapitulates features of a mild presentation of the disease. The objective of this study was to determine whether changing the balance between synthesis and degradation of collagen by chronic treatment with doxycycline, a nonspecific matrix metalloproteinase (MMP) inhibitor, could prevent the development of vascular pathology in HT mice. After 3 months of treatment with doxycycline or placebo, 9-month-old HT or wild-type (WT) mice were subjected to surgical stressing of the aorta. A 3-fold increase in stress-induced aortic lesions found in untreated HT mice 1 week after intervention (cumulative score 4.5 ± 0.87 versus 1.3 ± 0.34 in WT, p < 0.001) was fully prevented in the doxycycline-treated group (1.1 ± 0.56, p < 0.001). Untreated HT mice showed increased MMP-9 activity in the carotid artery and decreased collagen content in the aorta; however, in doxycycline-treated animals there was normalization to the levels observed in WT mice. Doxycycline treatment inhibits the activity of tissue MMP and attenuates the decrease in the collagen content in aortas of mice haploinsufficient for collagen III, as well as prevents the development of stress-induced vessel pathology. The results suggest that doxycycline merits clinical testing as a treatment for vEDS.

Circulating transforming growth factor-beta in Marfan syndrome.

BACKGROUND: Marfan syndrome (MFS) is caused by mutations in the fibrillin-1 gene and dysregulation of transforming growth factor-beta (TGF-beta). Recent evidence suggests that losartan, an angiotensin II type 1 blocker that blunts TGF-beta activation, may be an effective treatment for MFS. We hypothesized that dysregulation of TGF-beta might be mirrored in circulating TGF-beta concentrations. METHODS AND RESULTS: Serum obtained from MFS mutant mice (Fbn1(C1039G/+)) treated with losartan was analyzed for circulating TGF-beta1 concentrations and compared with those from placebo-treated and wild-type mice. Aortic root size was measured by echocardiography. Data were validated in patients with MFS and healthy individuals. In mice, circulating total TGF-beta1 concentrations increased with age and were elevated in older untreated Fbn1(C1039G/+) mice compared with wild-type mice (P=0.01; n=16; mean+/-SEM, 115+/-8 ng/mL versus n=17; mean+/-SEM, 92+/-4 ng/mL). Losartan-treated Fbn1(C1039G/+) mice had lower total TGF-beta1 concentrations compared with age-matched Fbn1(C1039G/+) mice treated with placebo (P=0.01; n=18; 90+/-5 ng/mL), and circulating total TGF-beta1 levels were indistinguishable from those of age-matched wild-type mice (P=0.8). Correlation was observed between circulating TGF-beta1 levels and aortic root diameters in Fbn1(C1039G/+) and wild-type mice (P=0.002). In humans, circulating total TGF-beta1 concentrations were elevated in patients with MFS compared with control individuals (P<0.0001; n=53; 15+/-1.7 ng/mL versus n=74; 2.5+/-0.4 ng/mL). MFS patients treated with losartan (n=55) or beta-blocker (n=80) showed significantly lower total TGF-beta1 concentrations compared with untreated MFS patients (P< or =0.05). CONCLUSIONS: Circulating TGF-beta1 concentrations are elevated in MFS and decrease after administration of losartan, beta-blocker therapy, or both and therefore might serve as a prognostic and therapeutic marker in MFS.

Contemporary management of vascular complications associated with Ehlers-Danlos syndrome.

OBJECTIVES: There has been debate regarding the safety of performing elective procedures in patients with vascular manifestations associated with Ehlers-Danlos syndrome (EDS). The purpose of this study was to review the surgical management and clinical outcomes of EDS patients undergoing vascular procedures at a tertiary medical center with multimodality expertise in connective tissue disorders. METHODS: All patients with EDS undergoing endovascular and open vascular procedures at a single-institution academic medical center from 1994 to 2009 were retrospectively reviewed. Clinical data were evaluated including patient demographics, length of stay (LOS), and mortality outcomes during hospital course and long-term follow-up. RESULTS: A total of 40 patients with EDS were identified, including individuals diagnosed with classic (n = 15), hypermobility (n = 16), and vascular (n = 9) types of EDS. These patients collectively underwent 45 endovascular and 18 open procedures for vascular disease during the time period, including embolization (n = 37), angioplasty (n = 8), arterial bypass (n = 5), and aortic aneurysm repair (n = 13). All cases were performed electively, except for one (2%) urgent endovascular and one (5%) emergent open procedure. Endovascular procedures were associated with a median LOS (interquartile range [IQR]) of 2 (1 to 3) days with no procedure-related mortality or in-hospital deaths among all EDS types, whereas open vascular procedures had median LOS (IQR) of 6 (5 to 8) days with one (6%) in-hospital death occurring in a vascular EDS patient. Survival free of any complication at 5 years was 85% and 54% following endovascular and open procedures, respectively. CONCLUSIONS: The elective surgical management of vascular disorders in EDS patients using open and endovascular procedures has been associated with good outcomes. Our results suggest that vascular interventions in these EDS patients can be safely performed and should not be withheld until rupture or acute symptoms arise.

The phenotypic spectrum of contiguous deletion of CYP21A2 and tenascin XB: quadricuspid aortic valve and other midline defects.

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is an autosomal recessive disorder and is the most common cause of ambiguous genitalia in the newborn. The genes encoding 21-hydroxylase, CYP21A2, and tenascin-X (TNX), TNXB, are located within the HLA complex, in a region of high gene density termed the RCCX module. The module has multiple pseudogenes as well as tandem repeat sequences that promote misalignment during meiosis leading to complex gene rearrangements, deletions and gene conversion events. CYP21A2 mutations cause CAH, and TNX deficiency has been identified as a cause of hypermobility type Ehlers-Danlos syndrome (EDS). Here we report on a three-generation family with a heterozygous deletion encompassing CYP21A2 and TNXB that initially came to medical attention due to the diagnosis of CAH in the proposita. Southern blotting and PCR-based analysis of the RCCX module revealed a CYP21A2 deletion extending into TNXB in one allele and a CYP21A2 point mutation in the other allele. Family history is notable for joint hypermobility. Additional radiological and clinical investigations showed a quadricuspid aortic valve, single kidney, bicornuate uterus and a bifid uvula in the proposita, and mitral valve prolapse in her mother. These findings further delineate the phenotype of the CAH-TNX contiguous gene deletion syndrome and point to an intersection of connective tissue dysplasias with a common gene-mediated endocrine disorder.

Syndrome of occipitoatlantoaxial hypermobility, cranial settling, and chiari malformation type I in patients with hereditary disorders of connective tissue.

OBJECT: Chiari malformation Type I (CM-I) is generally regarded as a disorder of the paraxial mesoderm. The authors report an association between CM-I and hereditary disorders of connective tissue (HDCT) that can present with lower brainstem symptoms attributable to occipitoatlantoaxial hypermobility and cranial settling. METHODS: The prevalence of HDCT was determined in a prospectively accrued cohort of 2813 patients with CM-I. All patients underwent a detailed medical and neuroradiological workup that included an assessment of articular mobility. Osseous structures composing the craniocervical junction were investigated morphometrically using reconstructed 3D computed tomography and plain x-ray images in 114 patients with HDCT/CM-I, and the results were compared with those obtained in patients with CM-I (55 cases) and healthy control individuals (55 cases). RESULTS: The diagnostic criteria for Ehlers-Danlos syndrome and related HDCT were met in 357 (12.7%) of the 2813 cases. Hereditability was generally compatible with a pattern of autosomal dominant transmission with variable expressivity. The diagnostic features of HDCT/CM-I were distinguished from those of CM-I by clinical stigmata of connective tissue disease, a greater female preponderance (8:1 compared with 3:1, p < 0.001), and a greater incidence of lower brainstem symptoms (0.41 compared with 0.11, p < 0.001), retroodontoid pannus formation (0.71 compared with 0.11, p < 0.001), and hypoplasia of the oropharynx (0.44 compared with 0.02, p < 0.001). Measurements of the basion-dens interval, basion-atlas interval, atlas-dens interval, dens-atlas interval, clivus-atlas angle, clivus-axis angle, and atlas-axis angle were the same in the supine and upright positions in healthy control individuals and patients with CM-I. In patients with HDCT/CM-I, there was a reduction of the basion-dens interval (3.6 mm, p < 0.001), an enlargement of the basion-atlas interval (3.0 mm, p < 0.001), and a reduction of the clivus-axis angle (10.8 degrees, p < 0.001), clivus-atlas angle (5.8 degrees, p < 0.001), and atlas-axis angle (5.3 degrees, p < 0.001) on assumption of the upright position. These changes were reducible by cervical traction or returning to the supine position. CONCLUSIONS: The identification of HDCT in 357 patients with CM-I establishes an association between two presumably unrelated mesodermal disorders. Morphometric evidence in this cohort-cranial settling, posterior gliding of the occipital condyles, and reduction of the clivus-axis angle, clivus-atlas angle, and atlas-axis angle in the upright position-suggests that hypermobility of the occipitoatlantal and atlantoaxial joints contributes to retroodontoid pannus formation and symptoms referable to basilar impression.

Aortic Dissection in Patients With Genetically Mediated Aneurysms: Incidence and Predictors in the GenTAC Registry.

BACKGROUND: Aortic dissection (AoD) is a serious complication of thoracic aortic aneurysm (TAA). Relative risk for AoD in relation to TAA etiology, incidence, and pattern after prophylactic TAA surgery are poorly understood. OBJECTIVES: This study sought to determine the incidence, pattern, and relative risk for AoD among patients with genetically associated TAA. METHODS: The population included adult GenTAC participants without AoD at baseline. Standardized core laboratory tests classified TAA etiology and measured aortic size. Follow-up was performed for AoD. RESULTS: Bicuspid aortic valve (BAV) (39%) and Marfan syndrome (MFS) (22%) were the leading diagnoses in the studied GenTAC participants (n = 1,991). AoD occurred in 1.6% over 3.6 ± 2.0 years; 61% of AoD occurred in patients with MFS. Cumulative AoD incidence was 6-fold higher among patients with MFS (4.5%) versus others (0.7%; p < 0.001). MFS event rates were similarly elevated versus those in patients with BAV (0.3%; p < 0.001). AoD originated in the distal arch or descending aorta in 71%; 52% of affected patients, including 68% with MFS, had previously undergone aortic grafting. In patients with proximal aortic surgery, distal aortic size (descending thoracic, abdominal aorta) was larger among patients with AoD versus those without AoD (both p < 0.05), whereas the ascending aorta size was similar. Conversely, in patients without previous surgery, aortic root size was greater in patients with subsequent AoD (p < 0.05), whereas distal aortic segments were of similar size. MFS (odds ratio: 7.42; 95% confidence interval: 3.43 to 16.82; p < 0.001) and maximal aortic size (1.86 per cm; 95% confidence interval: 1.26 to 2.67; p = 0.001) were independently associated with AoD. Only 4 of 31 (13%) patients with AoD had pre-dissection images that fulfilled size criteria for prophylactic TAA surgery at a subsequent AoD site. CONCLUSIONS: Among patients with genetically associated TAA, MFS augments risk for AoD even after TAA grafting. Although increased aortic size is a risk factor for subsequent AoD, events typically occur below established thresholds for prophylactic TAA repair.

Broadening the Spectrum of Ehlers Danlos Syndrome in Patients With Congenital Adrenal Hyperplasia.

CONTEXT: The contiguous gene deletion syndrome (CAH-X) was described in a subset (7%) of congenital adrenal hyperplasia (CAH) patients with a TNXA/TNXB chimera, resulting in deletions of CYP21A2, encoding 21-hydroxylase necessary for cortisol biosynthesis, and TNXB, encoding the extracellular matrix glycoprotein tenascin-X (TNX). This TNXA/TNXB chimera is characterized by a 120-bp deletion in exon 35 and results in TNXB haploinsufficiency, disrupted TGF-ß signaling, and an Ehlers Danlos syndrome phenotype. OBJECTIVE: The objective of the study was to determine the genetic status of TNXB and resulting protein defects in CAH patients with a CAH-X phenotype but not the previously described TNXA/TNXB chimera. Design, Settings, Participants, and Intervention: A total of 246 unrelated CAH patients were screened for TNXB defects. Genetic defects were investigated by Southern blotting, multiplex ligation-dependent probe amplification, Sanger, and next-generation sequencing. Dermal fibroblasts and tissue were used for immunoblotting, immunohistochemical, and coimmunoprecipitation experiments. MAIN OUTCOME MEASURES: The genetic and protein status of tenascin-X in phenotypic CAH-X patients was measured. RESULTS: Seven families harbor a novel TNXB missense variant c.12174C>G (p.C4058W) and a clinical phenotype consistent with hypermobility-type Ehlers Danlos syndrome. Fourteen CAH probands carry previously described TNXA/TNXB chimeras, and seven unrelated patients carry the novel TNXB variant, resulting in a CAH-X prevalence of 8.5%. This highly conserved pseudogene-derived variant in the TNX fibrinogen-like domain is predicted to be deleterious and disulfide bonded, results in reduced dermal elastin and fibrillin-1 staining and altered TGF-ß1 binding, and represents a novel TNXA/TNXB chimera. Tenascin-X protein expression was normal in dermal fibroblasts, suggesting a dominant-negative effect. CONCLUSIONS: CAH-X syndrome is commonly found in CAH due to 21-hydroxylase deficiency and may result from various etiological mechanisms.

Transforming growth factor-ß (TGF-ß) pathway abnormalities in tenascin-X deficiency associated with CAH-X syndrome.

Patients with congenital adrenal hyperplasia (CAH) with tenascin-X deficiency (CAH-X syndrome) have both endocrine imbalances and characteristic Ehlers Danlos syndrome phenotypes. Unlike other subtypes, tenascin-X-related Ehlers Danlos syndrome is caused by an extracellular matrix protein deficiency rather than a defect in fibrillar collagen or a collagen-modifying enzyme, and the understanding of the disease mechanisms is limited. We hypothesized that transforming growth factor-ß pathway dysregulation may, in part, be responsible for connective tissue phenotypes observed in CAH-X, due to this pathway's known role in connective tissue disorders. Fibroblasts and direct tissue from human skin biopsies from CAH-X probands and age- and sex-matched controls were screened for transforming growth factor-ß biomarkers known to be dysregulated in other hereditary disorders of connective tissue. In CAH-X fibroblast lines and dermal tissue, pSmad1/5/8 was significantly upregulated compared to controls, suggesting involvement of the bone morphogenetic protein pathway. Additionally, CAH-X samples compared to controls exhibited significant increases in fibroblast-secreted TGF-ß3, a cytokine important in secondary palatal development, and in plasma TGF-ß2, a cytokine involved in cardiac function and development, as well as palatogenesis. Finally, MMP-13, a matrix metalloproteinase important in secondary palate formation and tissue remodeling, had significantly increased mRNA and protein expression in CAH-X fibroblasts and direct tissue. Collectively, these results demonstrate that patients with CAH-X syndrome exhibit increased expression of several transforming growth factor-ß biomarkers and provide a novel link between this signaling pathway and the connective tissue dysplasia phenotypes associated with tenascin-X deficiency.

Transforming growth factor-ß and inflammation in vascular (type IV) Ehlers-Danlos syndrome.

BACKGROUND: Vascular Ehlers-Danlos syndrome (VEDS) causes reduced life expectancy because of arterial dissections/rupture and hollow organ rupture. Although the causative gene, COL3A1, was identified >20 years ago, there has been limited progress in understanding the disease mechanisms or identifying treatments. METHODS AND RESULTS: We studied inflammatory and transforming growth factor-ß (TGF-ß) signaling biomarkers in plasma and from dermal fibroblasts from patients with VEDS. Analyses were done in terms of clinical disease severity, genotype-phenotype correlations, and body composition and fat deposition alterations. VEDS subjects had increased circulating TGF-ß1, TGF-ß2, monocyte chemotactic protein-1, C-reactive protein, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and leptin and decreased interleukin-8 versus controls. VEDS dermal fibroblasts secreted more TGF-ß2, whereas downstream canonical/noncanonical TGF-ß signaling was not different. Patients with COL3A1 exon skipping mutations had higher plasma intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, and VEDS probands had abnormally high plasma C-reactive protein versus affected patients identified through family members before any disease manifestations. Patients with VEDS had higher mean platelet volumes, suggesting increased platelet turnover because of ongoing vascular damage, as well as increased regional truncal adiposity. CONCLUSIONS: These findings suggest that VEDS is a systemic disease with a major inflammatory component. C-reactive protein is linked to disease state and may be a disease activity marker. No changes in downstream TGF-ß signaling and increased platelet turnover suggest that chronic vascular damage may partially explain increased plasma TGF-ß1. Finally, we found a novel role for dysregulated TGF-ß2, as well as adipocyte dysfunction, as demonstrated through reduced interleukin-8 and elevated leptin in VEDS.