Hemangiomas: new insights and classification

Urea-modulated UT-B urea transporter internalization is clathrin- and caveolae-dependent in infantile hemangioma-derived vascular endothelial cells

The aim of this study was to investigate the manner of urea-modulated UT-B urea transporter (UT) internalization in infantile hemangioma-derived vascular endothelial cells (HemECs). The immunohistochemistry assay was performed to identify infancy hemangioma-derived endothelial cell line (XPTS-1) cells. Cell toxicity was detected with the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay. Quantitative real-time polymerase chain reaction and Western blot analysis were measured to analyze the expression of UT-B. UT-B internalization was observed by confocal microscopy. The clathrin inhibitor chlorpromazine (CPZ) and caveolin endocytic disrupter methyl-β-cyclodextrin (MβCD) were used in XPTS-1 cells transfected with UT-B-GFP to repress endocytosis. Urea-promoted UT-B expression in a concentration-dependent manner in an infantile XPTS-1 cell line. CPZ and MβCD significantly inhibited UT-B protein internalization. The pretreatment of UT-B-GFP cells with adaptor protein2 (AP2)-μ2-siRNA and caveolin-siRNA significantly inhibited UT-B protein internalization. Our findings suggested that urea-mediated UT-B UT internalization is clathrin and caveolae dependent in infantile HemECs.

Pulsed dye laser and topical timolol gel versus pulse dye laser in treatment of infantile hemangioma: A double-blind randomized controlled trial

Background:

Infantile hemangioma (IH) is the most common tumor during infancy that usually appears as macular and gradually becomes a plaque or tumor. Approximately, 20% of all IH cases results in adverse effects and the Pulsed dye laser (PDL) 585 nm is a vascular laser leading to selective the micro vascular damage. Results of studies on non-selective B-blockers (e.g., timolol) indicate their effectiveness in preventing hemangioma growth. The aim of this study is a comparison of PDL plus timolol and PDL in the treatment of IH.

Materials and Methods:

This double-blind study was carried out on 30 infants (1-12 months old) and the patients were divided into two groups. Group A was treated with the four sessions PDL and the timolol gel 0.05% and Group B with PDL.

Results:

There were no differences in the mean age of patients for the diagnosis of hemangioma (Group A: 32.69 ± 24.64 days, Group B: 25.69 ± 21.16 days, P = 0.39) and the mean age at the start of the treatment (Group A: 148.125 ± 85.88 days, Group B: 146.25 ± 60.87 days, P = 0.94). There were a statistical difference in the mean of lesion size reduction (Group A: 17.62 ± 6.97 cm and Group B: 12 ± 5.71 cm, P = 0.018), mean percentage change in size mean (Group A: 71079 ± 23.41% and Group B: 54.59 ± 25.46%, P = 0.050) visual analog scale (Group A: 7.19 ± 1.51, Group B: 5.62 ± 1.78, P = 0.012) after treatment. There was no correlation between the time of beginning the treatment and the results (P = 0.857).

Conclusions:

Application of timolol with PDL is accompanied by the highest efficacy, cost benefits and the short time of treatment.

Malignant transformation of infantile hemangioma to angiosarcoma: response to chemotherapy with bevacizumab

We describe a child initially diagnosed with multi-focal infantile hemangioma (cutaneous, hepatic, pulmonary), a benign vascular lesion, which underwent malignant transformation to angiosarcoma. The use of anti-angiogenic agents, such as bevacizumab, an anti-vascular endothelial growth factor (VEGF) antibody, has been reported in adults with angiosarcoma. Treatment with chemotherapy (gemcitabine and docetaxel) and bevacizumab resulted in disease response with progression free survival of 12 months. This report describes the response to chemotherapy and bevacizumab in a child with angiosarcoma and highlights the potential for malignant transformation of benign vascular lesions and the need for careful monitoring.

Management of infantile hemangiomas: current trends

Infantile hemangiomas (IH) are common vascular tumours. IH have a characteristic natural course. They proliferate rapidly during the early infantile period followed by a period of gradual regression over several years. Most of the uncomplicated IH undergo spontaneous involution, with a small proportion of cases requiring intervention. These are children with IH in life-threatening locations, local complications like haemorrhage, ulceration and necrosis and functional or cosmetic disfigurements. Systemic corticosteroids have been the first line of treatment for many years. Recently, non-selective beta-blockers, such as oral propranalol and topical timolol, have emerged as promising and safer therapies. Other treatment options include interferon α and vincristine which are reserved for life-threatening haemangiomas that are unresponsive to conventional therapy. This review mainly focuses on the current trends and evidence-based approach in the management of IH.

Urea immunoliposome inhibits human vascular endothelial cell proliferation for hemangioma treatment

BACKGROUND

Urea injection has been used in hemangioma treatment as sclerotherapy. It shrinks vascular endothelial cells and induces degeneration, necrosis, and fibrosis. However, this treatment still has disadvantages, such as lacking targeting and difficulty in controlling the urea dosage. Thus, we designed a urea immunoliposome to improve the efficiency of treatment.

METHODS

The urea liposome was prepared by reverse phase evaporation. Furthermore, the urea immunoliposome was generated by coupling the urea liposome with a vascular endothelial growth factor receptor (VEGFR) monoclonal antibody using the glutaraldehyde cross-linking method. The influence of the urea immunoliposome on cultured human hemangioma vascular endothelial cells was observed preliminarily.

RESULTS

Urea immunoliposomes showed typical liposome morphology under a transmission electron microscope, with an encapsulation percentage of 54.4% and a coupling rate of 36.84% for anti-VEGFR. Treatment with the urea immunoliposome significantly inhibited the proliferation of hemangioma vascular endothelial cells (HVECs) in a time- and dose-dependent manner.

CONCLUSIONS

The urea immunoliposome that we developed distinctly and persistently inhibited the proliferation of HVECs and is expected to be used in clinical hemangioma treatment.

Evaluation of plasma tissue factor and tissue factor pathway inhibitor levels in childhood hemangiomas

BACKGROUND

The purpose of the study was to evaluate the plasma levels of tissue factor (TF), an angiogenic marker, and tissue factor pathway inhibitor (TFPI), an antiproliferative protein, in the childhood hemangiomas at proliferative and regressive stages.

PROCEDURE

The study included 30 patients with hemangiomas and 30 healthy children. Localization, number, stage, type, duration of growth, and complications of the hemangiomas were determined. Venous blood samples from all individuals were collected into citrated tubes and centrifuged. Supernatant plasma was separated, aliquated, and stored at -70 degrees C until samples could be assayed. Plasma levels of TF and TFPI were measured with quantitative ELISA kits.

RESULTS

Plasma TF and TFPI levels did not show any significant difference between the study and control groups. When plasma TF and TFPI levels of the children in the control group and in the study group who were in proliferative and regressive stage were compared to each other, no statistically significant difference could be detected.

CONCLUSIONS

Plasma TF and TFPI levels of our patients with hemangiomas were not different from healthy children and they did not show any significant difference in proliferative and regressive stages.

[Infantile hemangiomas: differential diagnosis and associated anomalies]

Infantile hemangiomas are frequent benign vascular tumors that are often easily recognized. However, the diagnosis between infantile hemangiomas and other vascular tumors, whether benign or malignant, may be difficult. This chapter describes the different clinical presentations of hemangiomas and details the investigations that are needed to confirm the nature of the lesion and to diagnose the potentially associated anomalies. Knowledge on differential diagnosis enables clinicians to detect hemangiomas that can lead to complications and that necessitate a multidisciplinary approach.

Basic science and clinical aspects of vascular anomalies

PURPOSE OF REVIEW

Patients with vascular and lymphatic anomalies are often 'medical orphans' ascertained through distinct medical specialists. Multidisciplinary vascular anomalies programs provide focused expertise in diagnosis and treatment for patients. National and international workshops on vascular anomalies are fostering clinical and basic science research to enhance our understanding of vascular development and vascular anomalies. Herewith is presented an update of recent advances in the study of vascular/lymphatic anomalies.

RECENT FINDINGS

New original findings include (1) the identification of distinct cell surface markers and other cellular properties in hemangiomas and vascular malformations relevant to vascular development, (2) the discovery of novel genetic mutations and susceptibility genes in patients with vascular anomalies, (3) recognition of new risk stratifications and clinical issues for patients with hemangiomas and vascular malformations, and (4) the elucidation of sequelae from the disorders as well as side effects of recent and previous therapies for vascular anomalies.

SUMMARY

Vascular anomalies are an attractive model for the study of human disorders of vasculogenesis and angiogenesis. The etiology of these disorders is unclear and likely represents a multifactorial process. Clinical clues are leading to scientific investigations that may enable targeted therapies, prevention strategies, or both.