Critical role of Aquaporin-1 and telocytes in infantile hemangioma response to propranolol beta blockade.

Propranolol, a nonselective ß-adrenergic receptor (ADRB) antagonist, is the first-line therapy for severe infantile hemangiomas (IH). Since the incidental discovery of propranolol efficacy in IH, preclinical and clinical investigations have shown evidence of adjuvant propranolol response in some malignant tumors. However, the mechanism for propranolol antitumor effect is still largely unknown, owing to the absence of a tumor model responsive to propranolol at nontoxic concentrations. Immunodeficient mice engrafted with different human tumor cell lines were treated with anti-VEGF bevacizumab to create a model sensitive to propranolol. Proteomics analysis was used to reveal propranolol-mediated protein alteration correlating with tumor growth inhibition, and Aquaporin-1 (AQP1), a water channel modulated in tumor cell migration and invasion, was identified. IH tissues and cells were then functionally investigated. Our functional protein association networks analysis and knockdown of ADRB2 and AQP1 indicated that propranolol treatment and AQP1 down-regulation trigger the same pathway, suggesting that AQP1 is a major driver of beta-blocker antitumor response. Examining AQP1 in human hemangioma samples, we found it exclusively in a perivascular layer, so far unrecognized in IH, made of telocytes (TCs). Functional in vitro studies showed that AQP1-positive TCs play a critical role in IH response to propranolol and that modulation of AQP1 in IH-TC by propranolol or shAQP1 decreases capillary-like tube formation in a Matrigel-based angiogenesis assay. We conclude that IH sensitivity to propranolol may rely, at least in part, on a cross talk between lesional vascular cells and stromal TCs.

Early initiation of treatment with oral propranolol for infantile hemangioma improves success rate.

BACKGROUND/OBJECTIVES: Early referral and treatment of infantile hemangioma (IH) is a major challenge for treatment success. However, there is a lack of data supporting a specific threshold for initiating treatment with oral propranolol. The aim of this analysis was to find factors, such as age at treatment initiation, leading to a higher success rate with oral propranolol treatment. METHODS: Based on data from the pivotal phase 2-3 clinical trial of oral propranolol in IH, we used Generalized Additive Model (GAM) charts with Generalized Linear Models (GLM), then a rule discovery algorithm, to identify sub-groups presenting a high probability of occurrence of the predefined outcome (i.e., success [complete or nearly complete resolution of the target hemangioma] at 6 months of treatment). RESULTS: Our analyses identified that patients who started oral propranolol 3 mg/kg/day before the age of 10 weeks had a success rate of 86%, higher than the 60% success rate for all patients that received the same regimen commencing after 10 weeks of age. CONCLUSIONS: Treatment initiation before 10 weeks of age was associated with a significantly higher rate of treatment success with oral propranolol 3 mg/kg/day. Infants with IH requiring treatment should be referred to an expert center and treated as soon as possible.

Medical management of vascular anomalies of the head and neck.

Depending on impairment, treatment of vascular anomalies is decided on a case-by-case basis in pluridisciplinary consultations. Interventional treatments, especially surgery and sclerotherapy, are usually partially efficient and management of patients with vascular anomalies increasingly involves the use of medical drugs. The most common vascular tumor is infantile hemangioma where first-line medical treatment, when necessary, is propranolol. Kasabach-Merritt phenomenon is now largely treated with sirolimus whereas first-line treatment of coagulation disorders associated with venous malformations is based on low-molecular-weight heparins or direct anticoagulants. Sirolimus is the standard treatment for painful inflammatory manifestations of low-flow vascular malformations such capillary, venous, and lymphatic malformations that can occur singly or in combination but PIK3CA inhibitors, originally developed in oncology, have shown promising results in patients with PIK3CA-related overgrowth spectrum. Currently, medical treatments are poorly developed for high-flow malformations such as arteriovenous malformations. However, new research aimed at delineating the different arteriovenous malformations based on molecular findings has given new hope for future development of targeted therapies.

Is Infantile Hemangioma a Neuroendocrine Tumor?

Infantile hemangioma (IH) is the most common infantile tumor, affecting 5-10% of newborns. Propranolol, a nonselective ß-adrenergic receptor (ADRB) antagonist, is currently the first-line treatment for severe IH; however, both its mechanism of action and its main cellular target remain poorly understood. Since betablockers can antagonize the effect of natural ADRB agonists, we postulated that the catecholamine produced in situ in IH may have a role in the propranolol response. By quantifying catecholamines in the IH tissues, we found a higher amount of noradrenaline (NA) in untreated proliferative IHs than in involuted IHs or propranolol-treated IHs. We further found that the first three enzymes of the catecholamine biosynthesis pathway are expressed by IH cells and that their levels are reduced in propranolol-treated tumors. To study the role of NA in the pathophysiology of IH and its response to propranolol, we performed an in vitro angiogenesis assay in which IH-derived endothelial cells, pericytes and/or telocytes were incorporated. The results showed that the total tube formation is sensitive to propranolol only when exogenous NA is added in the three-cell model. We conclude that the IH's sensitivity to propranolol depends on crosstalk between the endothelial cells, pericytes and telocytes in the context of a high local amount of local NA.

Cutaneous Infantile Haemangiomas with Intracranial and Intraspinal Involvement: A European Multicentre Experience and Review.

Infantile haemangiomas are very common benign tumours in the first months of life. They are mostly cutaneous; however, extracutaneous lesions are possible, and occur in very rare cases in the central nervous system. A European multicentre observational retrospective study was conducted in the last 5 years. Seven patients with intracranial or intraspinal infantile haemangiomas were selected and treated with oral propranolol. Propranolol was interrupted after complete or almost complete resolution of infantile haemangiomas. All patients tolerated the treatment well without side-effects. Central nervous system infantile haemangiomas are probably underestimated due to the frequent absence of symptoms and their spontaneous involution. However, they should be investigated in case of segmental cutaneous infantile haemangiomas, particularly on the head, neck, upper trunk, lumbar or sacral area in order to diagnosis intra-central nervous system involvement at an early stage.

Germline Loss-of-Function Mutations in EPHB4 Cause a Second Form of Capillary Malformation-Arteriovenous Malformation (CM-AVM2) Deregulating RAS-MAPK Signaling.

BACKGROUND: Most arteriovenous malformations (AVMs) are localized and occur sporadically. However, they also can be multifocal in autosomal-dominant disorders, such as hereditary hemorrhagic telangiectasia and capillary malformation (CM)-AVM. Previously, we identified RASA1 mutations in 50% of patients with CM-AVM. Herein we studied non-RASA1 patients to further elucidate the pathogenicity of CMs and AVMs. METHODS: We conducted a genome-wide linkage study on a CM-AVM family. Whole-exome sequencing was also performed on 9 unrelated CM-AVM families. We identified a candidate gene and screened it in a large series of patients. The influence of several missense variants on protein function was also studied in vitro. RESULTS: We found evidence for linkage in 2 loci. Whole-exome sequencing data unraveled 4 distinct damaging variants in EPHB4 in 5 families that cosegregated with CM-AVM. Overall, screening of EPHB4 detected 47 distinct mutations in 54 index patients: 27 led to a premature stop codon or splice-site alteration, suggesting loss of function. The other 20 are nonsynonymous variants that result in amino acid substitutions. In vitro expression of several mutations confirmed loss of function of EPHB4. The clinical features included multifocal CMs, telangiectasias, and AVMs. CONCLUSIONS: We found EPHB4 mutations in patients with multifocal CMs associated with AVMs. The phenotype, CM-AVM2, mimics RASA1-related CM-AVM1 and also hereditary hemorrhagic telangiectasia. RASA1-encoded p120RASGAP is a direct effector of EPHB4. Our data highlight the pathogenetic importance of this interaction and indicts EPHB4-RAS-ERK signaling pathway as a major cause for AVMs.

Infantile haemangioma.

With a prevalence of 4·5%, infantile haemangiomas are the most common benign tumours of infancy, arising in the first few weeks of life and exhibiting a characteristic sequence of growth and spontaneous involution. Most infantile haemangiomas do not require therapy. However, to identify at-risk haemangiomas, close follow-up is crucial in the first weeks of life; 80% of all haemangiomas reach their final size by 3 months of age. The main indications for treatment are life-threatening infantile haemangioma (causing heart failure or respiratory distress), tumours posing functional risks (eg, visual obstruction, amblyopia, or feeding difficulties), ulceration, and severe anatomic distortion, especially on the face. Oral propranolol is now the first-line treatment, which should be administered as early as possible to avoid potential complications. Haemangioma shrinkage is rapidly observed with oral propranolol, but a minimum of 6 months of therapy is recommended.

A randomized, controlled trial of oral propranolol in infantile hemangioma.

BACKGROUND: Oral propranolol has been used to treat complicated infantile hemangiomas, although data from randomized, controlled trials to inform its use are limited. METHODS: We performed a multicenter, randomized, double-blind, adaptive, phase 2-3 trial assessing the efficacy and safety of a pediatric-specific oral propranolol solution in infants 1 to 5 months of age with proliferating infantile hemangioma requiring systemic therapy. Infants were randomly assigned to receive placebo or one of four propranolol regimens (1 or 3 mg of propranolol base per kilogram of body weight per day for 3 or 6 months). A preplanned interim analysis was conducted to identify the regimen to study for the final efficacy analysis. The primary end point was success (complete or nearly complete resolution of the target hemangioma) or failure of trial treatment at week 24, as assessed by independent, centralized, blinded evaluations of standardized photographs. RESULTS: Of 460 infants who underwent randomization, 456 received treatment. On the basis of an interim analysis of the first 188 patients who completed 24 weeks of trial treatment, the regimen of 3 mg of propranolol per kilogram per day for 6 months was selected for the final efficacy analysis. The frequency of successful treatment was higher with this regimen than with placebo (60% vs. 4%, P<0.001). A total of 88% of patients who received the selected propranolol regimen showed improvement by week 5, versus 5% of patients who received placebo. A total of 10% of patients in whom treatment with propranolol was successful required systemic retreatment during follow-up. Known adverse events associated with propranolol (hypoglycemia, hypotension, bradycardia, and bronchospasm) occurred infrequently, with no significant difference in frequency between the placebo group and the groups receiving propranolol. CONCLUSIONS: This trial showed that propranolol was effective at a dose of 3 mg per kilogram per day for 6 months in the treatment of infantile hemangioma. (Funded by Pierre Fabre Dermatologie; ClinicalTrials.gov number, NCT01056341.).

Skin Patterns Associated with Upper Airway Infantile Haemangiomas: A Retrospective Multicentre Study.

The aim of this study was to define the skin patterns at high risk for upper airway infantile haemangioma. A retrospective multicentre French observational study was conducted between January 2006 and January 2015 and all confirmed airway haemangioma were included. Thirty-eight patients with airway haemangioma from 9 centres were included. Thirty-one patients had a cutaneous or mucosal haemangioma: 21 with a location considered at high risk for airway haemangioma (large segmental mandibular haemangioma), 4 with a very mild facial involvement (lower lip or S1 (frontotemporal segment according to Haggstrom and Frieden)) and 6 with either lesions of the neck or body, or association of both. We report here the largest cohort of airway haemangioma. A third of patients do not completely fit with the definition of the high-risk area of airway haemangioma. Segmental lower lip and neck involvement also seem to be very suggestive areas. Clinicians must be able to recognize these areas.

A prospective study of risk for Sturge-Weber syndrome in children with upper facial port-wine stain.

BACKGROUND: Upper facial port-wine stain (PWS) is a feature of Sturge-Weber syndrome (SWS). Recent studies suggest that the distribution of the PWS corresponds to genetic mosaicism rather than to trigeminal nerve impairment. OBJECTIVES: We sought to refine the cutaneous distribution of upper facial PWS at risk for SWS. METHODS: This was a prospective multicenter study of consecutive cases of upper facial PWS larger than 1 cm² located in the ophthalmic division of trigeminal nerve distribution in infants aged less than 1 year, seen in 8 French pediatric dermatology departments between 2006 and 2012. Clinical data, magnetic resonance imaging, and photographs were systematically collected and studied. PWS were classified into 6 distinct patterns. RESULTS: In all, 66 patients were included. Eleven presented with SWS (magnetic resonance imaging signs and seizure). Four additional infants had suspected SWS without neurologic manifestations. Hemifacial (odds ratio 7.7, P = .003) and median (odds ratio 17.08, P = .008) PWS patterns were found to be at high risk for SWS. A nonmedian linear pattern was not associated with SWS. LIMITATIONS: Small number of patients translated to limited power of the study. CONCLUSIONS: Specific PWS distribution patterns are associated with an increased risk of SWS. These PWS patterns conform to areas of somatic mosaicism. Terminology stipulating ophthalmic division of trigeminal nerve territory involvement in SWS should be abandoned.

Haemangioma family burden: creation of a specific questionnaire.

To develop and validate a specific questionnaire to assess burden on families of children with infantile haemangioma (IH): the Haemangioma Family Burden questionnaire (HFB). Items were generated from a literature review and a verbatim report from parents. Subsequently, a study was implemented at the Necker Hospital and the Pellegrin Children's Hospital for psychometric analysis. The HFB was refined via item reduction according to inter-question correlations, consensus among experts and exploratory factor analysis. A 20-item questionnaire, grouped into 5 dimensions, was obtained. Construct validity was demonstrated and HFB showed good internal coherence (Cronbach's α: 0.93). The HFB was significantly correlated with the mental dimension of the Short-Form-12 (r = -0.75), and the Psychological General Well-Being Index (r = -0.61). HFB scores differed significantly according to the size and localization of the IH. A validated tool for assessing the burden on families of children with IH is now available.

Treatment of infantile haemangiomas: recommendations of a European expert group.

UNLABELLED: With a prevalence of 2.6-4.5 %, infantile haemangiomas (IH) represent the most common tumour of infancy. While the majority of IH does not require therapy and regresses spontaneously, about 10 % of IH exhibit complications such as obstruction, ulceration or disfigurement. With the advent of oral propranolol, many conventional treatment options have become obsolete. This paper summarizes current recommendations for management of complicated IH. These recommendations have been written by an expert group after a consensus process including bibliographic review, several drafts of synthesis, meetings with quantitative voting system and redaction of an approved final manuscript. CONCLUSION: Oral propranolol is the first-line agent for the treatment of complicated IH. WHAT IS KNOWN: • Infantile haemangiomas (IH) are the most common tumours of infancy. Within a very short period after its discovery and long before the publication of randomized controlled trials, propranolol has become the number one agent for the treatment of complicated IH. What is New: • We report IH treatment recommendations of an international, interdisciplinary team of experts, based on an up-to-date review of the literature.

[Infantile hemangiomas: the revolution of beta-blockers]. / Hémangiomes infantiles: la revolution des bêtabloquants.

Infantile hemangioma is the consequence of both postnatal vasculogenesis and angiogenesis. Hypoxia appears to play an important role as a contributory factor. Infantile hemangiomas have variable clinical features: superficial, deep or mixed. They can be localized or segmental involving a large skin area. Localized infantile hemangiomas are usually benign, unless they are located near a noble structure (airway orbit...), while segmental infantile hemangioma may be associated with complex underlying birth defects (PHACES and SACRAL syndromes). Clinical follow-up of infants with infantile hemangioma must be particularly careful in the first weeks of life since 80% of all infantile hemangiomas have reached their final size at age 5 months. A majority of infantile hemangiomas are mild and do not required any treatment. Main indications for treatment are: vital risk (heart failure, respiratory distress), functional risk (amblyopia, swallowing disorders...), painful ulceration and disfigurement (face involvement of nose, lips...). Propranolol, has been quickly adopted as the first line medical treatment for complicated infantile hemangioma; and it is the only treatment to have a marketing authorization in this indication. It is recommended to begin the treatment as early as possible before three months of age to minimize the risk of complications and sequelae.

RASA1 mutations and associated phenotypes in 68 families with capillary malformation-arteriovenous malformation.

Capillary malformation-arteriovenous malformation (CM-AVM) is an autosomal-dominant disorder, caused by heterozygous RASA1 mutations, and manifesting multifocal CMs and high risk for fast-flow lesions. A limited number of patients have been reported, raising the question of the phenotypic borders. We identified new patients with a clinical diagnosis of CM-AVM, and patients with overlapping phenotypes. RASA1 was screened in 261 index patients with: CM-AVM (n = 100), common CM(s) (port-wine stain; n = 100), Sturge-Weber syndrome (n = 37), or isolated AVM(s) (n = 24). Fifty-eight distinct RASA1 mutations (43 novel) were identified in 68 index patients with CM-AVM and none in patients with other phenotypes. A novel clinical feature was identified: cutaneous zones of numerous small white pale halos with a central red spot. An additional question addressed in this study was the "second-hit" hypothesis as a pathophysiological mechanism for CM-AVM. One tissue from a patient with a germline RASA1 mutation was available. The analysis of the tissue showed loss of the wild-type RASA1 allele. In conclusion, mutations in RASA1 underscore the specific CM-AVM phenotype and the clinical diagnosis is based on identifying the characteristic CMs. The high incidence of fast-flow lesions warrants careful clinical and radiologic examination, and regular follow-up.

Topical timolol for small hemangiomas of infancy.

Propranolol has become the treatment of choice of large and complicated infantile hemangiomas. There is a controversy concerning the safety of systemic propranolol. Here we show that topical use of the beta-blocker timolol can also inhibit the growth and promote regression of infantile hemangiomas. In this case series we treated 11 infantile hemangiomas in nine children including six preterm babies with the nonselective betablocker timolol. A timolol containing gel was manufactured from an ophthalmic formulation of timolol 0.5% eyedrops. This gel was applied using a standardized occlusive dressing (Finn-Chambers) containing approximately 0.25 mg of timolol. In all infants topical timolol was associated with growth arrest, a reduction in redness and thickness within the first 2 weeks. Seven hemangiomas showed almost complete resolution, and four became much paler and thinner. No data are available on the transdermal absorption of timolol. Even supposing complete absorption of timolol from the occlusive dressing, a maximum dose of 0.25 mg of timolol would result per day and hemangioma. Regression of infantile hemangiomas treated using 0.5% timolol gel in this case series occurred earlier than spontaneous regression which is generally not observed before the age of 9-12 months. The promising results need to be verified in prospective randomized trials on topical beta blocker administration for infantile hemangiomas which should address dose, duration, and mode of application.

Diagnostic value of polymerase chain reaction analysis of skin biopsies in purpura fulminans.

Even though prompt diagnosis and treatment of purpura fulminans (PF) is essential to reduce mortality, early administration of antibiotics may preclude identification of the causative agent by standard bacterial cultures and thus render definitive diagnosis impossible. Here we present a case of an infant with PF and negative bacterial cultures for whom polymerase chain reaction (PCR) analysis of a cutaneous biopsy specimen obtained 4 days after initiation of antibiotics identified the genomic sequence of Neisseria meningitidis genogroup C. When bacterial cultures fail to provide useful information, PCR of skin biopsy specimens can be a valuable diagnostic tool in PF.

IFAG and childhood rosacea: a possible link?

Idiopathic facial aseptic granuloma (IFAG) is a disorder that usually occurs during early childhood. Its pathogenesis remains poorly understood. The objective of this study was to investigate possible relationships between IFAG and childhood rosacea. This was a retrospective multicenter study of patients attending four French dermatologic centers diagnosed with IFAG between October 2000 and July 2007. Patients and their parents were asked to come for a follow-up visit or to make an appointment for a telephone interview. Clinical symptoms of childhood rosacea were recorded: flushing, permanent or recurrent erythema; facial telangiectasia; papules and pustules on the face without comedones or microcysts; preferential location of the lesions on the convexity of the face; and ophthalmologic involvement of rosacea (recurrent chalazions, conjunctival hyperemia, keratitis). Thirty-eight patients, 20 girls and 18 boys, were included in the study. The median age at the time of diagnosis of IFAG was 43 months, with a median follow-up of 3.9 years. Sixteen patients (42.1%) had at least two criteria of childhood rosacea, 11 of 32 (34.4%) with a single lesion and 5 of 6 (83.3%) with multiple lesions. Children with IFAG are at risk for childhood rosacea, and follow-up is advised, including periodic ophthalmologic assessment.