Cutaneous vascular anomalies. Part I. Hamartomas, malformations, and dilation of preexisting vessels

Unusual Genital Wart Lesions: A Case Series on Angiokeratoma of Fordyce

Angiokeratoma is a vascular cutaneous disorder that is generally asymptomatic and presents with multiple dark red to blue or black papules over the skin. The prevalence of angiokeratoma increases as the age increases and it is more common after third and fourth decades of life. There are different types of angiokeratoma which may be localized forms (angiokeratoma of Mibelli, angiokeratoma circumscriptum, solitary angiokeratoma, and angiokeratoma of the scrotum or vulva) or diffuse variant (angiokeratoma corporis diffusum). Here, we report a series of five rare cases of angiokeratoma of Fordyce, of which two cases had vulval involvement and one case showed lesions on unilateral scrotal wall which was unusual.

3D imaging of vascular anomalies using raster-scanning optoacoustic mesoscopy

OBJECTIVES

Vascular anomalies such as capillary malformations (CMs) and infantile hemangiomas (IHs) are common pediatric vascular disorders that are treated with therapeutic laser. The treatment method, however, relies on subjective evaluation of clinical findings and can have unpredictable results. Raster-scanning optoacoustic mesoscopy (RSOM) is an innovative imaging technology using pulsed-light laser to excite hemoglobin, generating ultrasound waves that are converted into three-dimensional images of tissues. RSOM can provide objective information about superficial structures such as the microvasculature of vascular anomalies.

MATERIALS AND METHODS

In this study, we explore the clinical potential of RSOM to study vascular anomalies before and after laser treatment. We scanned nine patients with CM (n = 6) and IH (n = 3) who underwent laser treatment and calculated the blood vessel volume.

RESULTS

Overall, there was a posttreatment volume increase in CM, and a decrease in IH.

CONCLUSION

These findings support the possibility that RSOM may have a role in developing an objective method of evaluating these lesions, leading to a tailored treatment approach and avoidance of adverse outcomes.

Silhouette Lymphangioma: An Unknown Macular Form of Cutaneous Lymphangioma

Unusual angiomatous or lymphangiomatous vascular malformations are rarely seen. One of them is lymphangioma (LA), which is a rare benign lymphovascular abnormality. LA is usually seen in the types of circumscriptum (or capillary), cavernous and cystic. Here, we report a unique case of LA with a patchy appearance. The patient presented due to unusual symptoms and eccentric clinical manifestation of the lesion. Here, we present a new lymphatic entity which was diagnosed as LA with its clinical, radiological and pathological findings. Written informed consent of the patient was obtained for this report. To the best of our knowledge this macular form of cutaneous LA has not been previously reported in literature. Macular LA should be kept in mind when faced with a colored long-term macular lesion on the skin.

Progressive cutaneous angiomatosis in the metatarsal region of a cat

CASE DESCRIPTION

A 1.5-year-old 4.0-kg (8.8-lb) castrated male mixed-breed cat was evaluated because of an 8-month history of repeated bleeding from a hole in the skin next to the left metatarsal pad.

CLINICAL FINDINGS

The cat had swelling in the distal region of the left pelvic limb, and blood dripped from a 2-mm-diameter hole in the skin adjacent and proximal to the metatarsal pad. Radiographic findings for the distal aspect of the left pelvic limb were compatible with a soft tissue inflammatory process. Results of histologic examination of a wedge biopsy sample, including the affected skin and subcutaneous tissue, indicated cutaneous angiomatosis. Angiography revealed anomalous vessels in the metatarsal region.

TREATMENT AND OUTCOME

Surgical resection of the skin, subcutaneous tissue, and anomalous vessels in the affected metatarsal region of the left pelvic limb was performed. However, similar abnormal clinical signs recurred and did not respond to treatment, including prednisolone (2.0 mg/kg [0.9 mg/lb], PO, q 12 h for 4 days) and doxycycline (10 mg/kg [4.5 mg/lb], PO, q 24 h). The left pelvic limb was amputated, and no recurrence of similar abnormalities in the cat's other limbs was evident within a 15-month follow-up period.

CLINICAL RELEVANCE

Findings in the cat of the present report highlighted that cutaneous angiomatosis could recur in a short period of time and that amputation of the affected limb was a viable treatment option when surgical resection was not successful.

Outcome with topical sirolimus for port wine stain malformations after unsatisfactory results with pulse dye laser treatment alone

We used a topical formulation of sirolimus for treating port wine stain (PWS). Although pulsed dye laser (PDL) is the current treatment of choice for PWS, fast neovascularization after treatment is a major drawback. With PDL therapy there has been insufficient improvement and frustrating side effects. The objective was to study the efficacy and safety of combining topical sirolimus with PDL as dual therapy in managing PWS. We report five PWS cases that were treated with PDL initially, followed by 0.5-1% topical sirolimus. With dual therapy there was significant improvement over a shorter duration. More published studies of topical sirolimus are needed to clarify the role of dual therapy in managing PWS associated with capillary malformations. We encourage further prospective and comparative studies with a larger sample size.

SIMILAR CASES PUBLISHED

1.

Spontaneous Venous Aneurysm: Report of a Non-traumatic Superficial Venous Aneurysm on the Distal Arm

Venous aneurysms are benign acquired vascular lesions. A 59-year-old man developed a lesion on his right wrist that would enlarge and flatten depending on whether his arm was dependent or elevated; he had no prior history of trauma to the site. Examination of his wrist revealed a soft, compressible nodule contiguous with venous structures in the area. The history and clinical appearance established the diagnosis of a superficial venous aneurysm. Venous aneurysms typically occur on extremities, either in the superficial or deep venous systems; a prior history of trauma is often elicited. Clinical observation may be appropriate for the management of venous aneurysms; however, symptomatic lesions often require excision. In conclusion, venous aneurysms often appear in adults; trauma may or may not precede their appearance. Asymptomatic lesions may be observed, whereas surgery may be necessary to resolve the condition if the aneurysm is symptomatic.

Classification of vascular malformations

With the term „hemangioma” different vascular anomalies are described. Here one has to discriminate the congenital vascular tumours from the vascular anomalies. But for a clear indication a definite classification is necessary. Basis is the actual ISSVA classification. In the latest version they have incorporated the embryological aspects of the Hamburg Classification. Especially in the vasculogenetic (″extratruncular″) malformations one found increasing genetic defects. Here is an overlap to the neuro-ectodermal syndromes. By this, common therapeutic strategies are in progress.

Misnomers in Dermatology

Background:

Dermatology lexicon is rich with descriptive terminology. However, for a variety of reasons, it also includes a number of misnomers. ObjectiveTo review the more commonly encountered and critically appraised misnomers in dermatology.

Methods:

A search of MEDLINE (1966 – 2004), eMedicine dermatology text and electronic versions of two standard dermatology texts, Fitzpatrick's Dermatology in General Medicine and Dermatology, was performed using the permutations of the terms: dermatology, skin, cutaneous, and misnomer.

Results:

Greater than 40 misnomers were identified.

Conclusions:

Misnomers in dermatology stem largely from lack of appreciation of underlying etiology or histopathological features of certain skin conditions, imprecise historical observations and erroneous eponymous credit. Historical, clinical, or histopathological explanations are used to clarify the nature of the misnomers, and in some cases suggestions for improved terminology are provided.

Surgical management of vascular anomalies in children at a tertiary care hospital in a resource-limited setting: a Tanzanian experience with 134 patients

BACKGROUND

Vascular anomalies pose major diagnostic and therapeutic challenges among pediatricians and pediatric surgeons practicing in resource limited countries. There is paucity of published data regarding this subject in Tanzania and Bugando Medical Centre in particular. This study describes our experiences on the challenges and outcome of surgical management of childhood vascular anomalies in our environment.

METHODS

Between January 2009 and December 2013, a prospective study on the surgical management of vascular anomalies was undertaken at Bugando Medical Centre.

RESULTS

A total of 134 patients (M; F = 1:2.5) were studied. The median age at presentation was 6 years. Of the 134 patients, 101 (75.4%) were diagnosed as having vascular tumors and 33 (24.6%) had vascular malformations. The head and the neck were the most frequent anatomical site recorded as having a tumor (56.7% of patients). Out of 134 patients, 129 (96.3%) underwent surgical treatment. Failure to respond to non-operative treatment (86.8%), huge disfiguring/obstructing mass (4.7%), infection (3.1%), ulceration (3.1%) and hemorrhage (2.3%) were indications for surgical intervention. Tumor excision and primary wound closure was the most common type of surgical procedure performed in 80.6% of patients. Surgical site infection was the most frequent complications accounting for 33.8% of cases. Mortality rate was 1.5%. Tumor excision and primary wound closure gave better outcome compared with other surgical options (p < 0.001). Outcome of injection sclerotherapy in 3 (3.7%) children, serial ligation of feeder vessels employed in 2 (1.6%), and conservative treatment in 5 (3.7%), were poor and required conversion to surgical excision. Despite low mortality rate recorded in this study, but ugly scar, 14 (20.6%) and limb deformity, 6 (8.8%) were problems. The overall result of surgical treatment at the end of follow up period was excellent in 108 (87.1%) patients.

CONCLUSION

Surgical excision and primary wound closure gave good outcome which could be employed in complicated and vascular anomalies which failed to respond to other treatment in regions with limited resources.

Diagnosis and Management of Infantile Hemangioma

Infantile hemangiomas (IHs) are the most common tumors of childhood. Unlike other tumors, they have the unique ability to involute after proliferation, often leading primary care providers to assume they will resolve without intervention or consequence. Unfortunately, a subset of IHs rapidly develop complications, resulting in pain, functional impairment, or permanent disfigurement. As a result, the primary clinician has the task of determining which lesions require early consultation with a specialist. Although several recent reviews have been published, this clinical report is the first based on input from individuals representing the many specialties involved in the treatment of IH. Its purpose is to update the pediatric community regarding recent discoveries in IH pathogenesis, treatment, and clinical associations and to provide a basis for clinical decision-making in the management of IH.

Vascular Anomalies Classification: Recommendations From the International Society for the Study of Vascular Anomalies

Vascular anomalies represent a spectrum of disorders from a simple "birthmark" to life- threatening entities. Incorrect nomenclature and misdiagnoses are commonly experienced by patients with these anomalies. Accurate diagnosis is crucial for appropriate evaluation and management, often requiring multidisciplinary specialists. Classification schemes provide a consistent terminology and serve as a guide for pathologists, clinicians, and researchers. One of the goals of the International Society for the Study of Vascular Anomalies (ISSVA) is to achieve a uniform classification. The last classification (1997) stratified vascular lesions into vascular malformations and proliferative vascular lesions (tumors). However, additional disease entities have since been identified that are complex and less easily classified by generic headings, such as capillary malformation, venous malformation, lymphatic malformation, etc. We hereby present the updated official ISSVA classification of vascular anomalies. The general biological scheme of the classification is retained. The section on tumors has been expanded and lists the main recognized vascular tumors, classified as benign, locally aggressive or borderline, and malignant. A list of well-defined diseases is included under each generic heading in the "Simple Vascular Malformations" section. A short definition is added for eponyms. Two new sections were created: one dealing with the malformations of individually named vessels (previously referred to as "truncular" malformations); the second groups lesions of uncertain or debated nature (tumor versus malformation). The known genetic defects underlying vascular anomalies are included in an appendix. This classification is meant to be a framework, acknowledging that it will require modification as new scientific information becomes available.

Pediatric dermatohistopathology--histopathology of skin diseases in newborns and infants

While neonatal skin physiology has been thoroughly examined using non-invasive techniques in recent years, only few systematic studies and review articles addressing the histopathology of neonatal skin have been published thus far. In most cases, histopathological findings of dermatoses in neonatal skin do not significantly differ from those seen in adult skin. Nevertheless, a comprehensive knowledge of embryonic and fetal skin development as well as the microanatomical structure of neonatal skin can contribute to a better understanding of various dermatoses of infancy. In the first part of this review article, we present the histopathological features of such skin diseases, which, though generally rare, almost exclusively appear during the first weeks of life due to distinctive structural and functional features of neonatal skin. The second part is dedicated to classic dermatoses of infancy and their histopathological features.

A clinical approach to diagnose patients with localized telangiectasia

Telangiectasia, or dilated blood vessels, may represent a benign condition or a marker of a much more serious internal or cutaneous malignancy (e.g., mycosis fungoides). They can be generalized or localized in distribution. 'Localized telangiectasia? can be macular or papular. Macular ones can be further divided into two major categories: primary and secondary. They can occur on their own (primary), after skin injury (e.g., sun damage, post-radiation therapy, after prolonged topical steroid application), or may arise due to an underlying condition (secondary). While telangiectases can spring from a multitude of possible causes, the location of the lesions, in combination with a careful history and exmination, often helps in elucidating the correct diagnosis. A patient with localized telangiectasia as a manifestation of malignancy may be difficult to diagnose, however the diagnosis is one of exclusion, and a thorough evaluation should be performed before diagnosing this condition. This article reviews possible conditions to consider in these patients and suggests an approach to their evaluation.

Late onset palmar angiokeratoma circumscriptum: An unusual presentation

Angiokeratomas (AK) are a group of capillary vascular malformations encompassing several unrelated conditions, predominantly seen on the lower extremities. AK can be classified into localized and diffuse forms. The diffuse forms comprise Fabry's disease, which is the result of α-galactosidase deficiency. The cutaneous AK includes the Mibelli type, the Fordyce type, angiokeratoma circumscriptum (AC), and ‘solitary and multiple papular angiokeratoma’. We describe a case of AC with unusual features including late onset and palmar affection. Amongst the possible therapeutic options, cryotherapy was considered. However, the patient was lost to follow up.

Ado-trastuzumab emtansine-associated telangiectasias in metastatic breast cancer: a case series

Treatment of HER2-positive metastatic breast cancer with ado-trastuzumab emtansine (T-DM1), a novel antibody-drug conjugate, has resulted in both improved progression-free and overall survival. Recognition and treatment of diverse adverse events related to T-DM1 is critical for safety and tolerability. The most frequent adverse events with T-DM1 include fatigue, diarrhea, anemia, elevated transaminases, and mild-to-moderate hemorrhagic events, which are thought to be related to induced thrombocytopenia. Here, we present five case series of cutaneous and mucosal telangiectasias, definitely related to T-DM1. The development of telangiectasias represents a newly recognized adverse effect of T-DM1. We provide description and timing of the telangiectasias and review the mechanisms that may explain the formation of these vascular lesions in association with T-DM1. Further, we describe associated bleeding events and propose that induced telangiectasias could represent an additional cause of T-DM1-associated hemorrhage.

The use of sodium tetradecyl sulphate for the treatment of venous malformations of the head and neck

INTRODUCTION

Vascular malformations have devastating cosmetic effects in addition to being associated with pain and bleeding. Sclerotherapy has been used as an effective therapeutic modality for the management of vascular malformations. The purpose of this case series is to describe our clinical experience of using sodium tetradecyl sulphate (STS) 3 % in the treatment of venous malformation lesions of head and neck.

MATERIALS AND METHODS

Thirteen patients were included in this study (three male and ten female; age range between 8 months and 54 years; mean age 18.2 years, ±SD 15.71). The patients were treated by 3 % STS intralesional injections. Of the thirteen patients treated, complete resolution occurred in four patients (28.57 %), a good response occurred in five patients (35.7 %), a moderate response in two patients (14.28 %), a mild response in two patients (14.28 %) and no response in one patient (7.14 %). The side effects encountered in all patients were pain and edema after injection which was controlled by oral analgesics and an intramuscular injection of dexamethasone. In addition, two patients developed a superficial ulceration (11.76 %) which healed uneventfully, and one patient developed ecchymosis after injection (5.88 %).

CONCLUSION

Sclerotherapy with 3 % STS is a simple, safe, and effective modality for the treatment of venous malformations.

Congenital and infantile skin lesions affecting the hand and upper extremity, part 1: vascular neoplasms and malformations

Many dermatologic conditions may be present on a newborn infant's upper extremity that can evoke concern for parents and/or primary caregivers. Although the pediatrician typically remains the first care provider, often these children are referred to specialists to diagnose and treat these lesions. Hand surgeons should be familiar with different infantile skin lesions on an upper extremity. Some lesions are best observed, whereas others require treatment with nonoperative measures, lasers, or surgical interventions. A 2-part series is presented to aid the hand surgeon in becoming familiar with these lesions. This part 1 article focuses on vascular neoplasms and malformations. Particular attention is paid to the multiple types of hemangiomas and hemangioendotheliomas, telangiectasias, angiokeratomas, as well as capillary, venous, and lymphatic malformations. Diagnostic tips and clinical photographs are provided to help differentiate among these lesions. In addition, the recommended treatment for each is discussed.

The dermal arteries of the human thumb pad

The arteries of the skin have been postulated to form a profound plexus at the dermal/hypodermal junction and a superficial plexus in the papillary dermis. Our article aims to rebut this concept and to provide an alternative description of the arrangement of the dermal arteries. Employing a novel technique, we produced digital volume data (volume size: 2739 × 2054 × 3000 μm(3) ; voxel size: 1.07 × 1.07 × 2 μm(3) ) from biopsies of the skin of the thumb pads of 15 body donors. Utilizing these data, we analysed the arrangement of the dermal arteries with the aid of virtual re-sectioning tools, and, in three specimens, with high-quality three-dimensional (3D) surface models. In all specimens we observed a tree-like ramification of discrete dermal arteries. The terminal branches of the arterial trees gave rise to the ascending segments of the capillary loops of the dermal papillae. None of the specimens showed a superficial arterial plexus. This suggests that the skin of the human thumb pad can be split in discrete 'arterial units'. Each unit represents the zone of the papillary dermis and epidermal/dermal junction, to which blood is supplied exclusively by the branches of a single dermal artery. The concept of dermal arterial units is in contrast to all existing descriptions of the architecture of the dermal arteries. However, whether it can be transferred to the skin of other body parts, remains to be tested. Likewise, the consequences of arterial units for understanding the mechanisms of wound healing and the appearance and genesis of skin diseases remain to be examined.

The risk of misinterpreting genital signs of sexual abuse in cadavers: a case report

The significance of genital findings in a case of suspected child sexual abuse has been widely debated in the past decades, as shown by the different classifications available in literature. In the case of postmortem examination, the search for signs of sexual abuse is considerably more difficult because of the superimposition of postmortem modifications, which may determine tissue modifications that can be mistaken for traumatic lesions. This study aims at reporting a case where presumed findings of the first autopsy were denied by histological analysis; in detail, what looked like a possible bruise of the hymen was correctly recognized as hypostasis (livor) of the hymenal tissue by histological analysis. This case report suggests caution in the analysis and discussion of genital lesions found during postmortem examination since the superimposition of cadaveric modifications may radically modify the morphology of soft tissues.

[A new location of angiokeratoma circumscriptum]

BACKGROUND

Angiokeratomas are papular telangiectasias having a common histology of ectasia of the superficial dermal vessels surmounted by a hyperkeratotic epidermis.

PATIENTS AND METHODS

The patient was a 9-year-old girl born of non-consanguineous parents after a well-followed pregnancy with problem-free delivery at term. From birth, she had a tumefaction of the left side of the nose and the left half of the upper lip that gradually increased in size without obstructing the nasal orifice and bled easily. Examination revealed the presence of tumefaction of the left nostril and the left half of the upper lip projecting towards the contralateral side especially in the nose. It was soft and painless, with the presence at the surface of dull red keratotic papules of 1 to 2 mm in diameter. Examination of the nasal mucosa revealed the same appearance of papules.

DISCUSSION

Angiokeratoma circumscriptum is a rare congenital malformation, the rarest of five types. Since its initial description in 1890, few cases have been reported. However, female predominance has been noted with a male/female sex ratio of 1/3. It appears to be due to a genetic mutation that is probably autosomal, but the site of which is still unknown. In view of the special features of this case, several diagnoses were suggested, including Rendu Osler's disease, superficial lymphangioma and verrucous angioma.

CONCLUSION

The particularity of this case is that it includes the first description of this site, which posed a therapeutic problem, especially concerning the choice of laser type to be used.

Telangiectasia macularis multiplex acquisita: a new entity in Chinese populations and an analysis of associated factors

BACKGROUND

  Telangiectasia macularis multiplex acquisita (TMMA) is a rarely documented entity with distinctive clinical manifestation. Most patients are middle-aged adults. It may be associated with other diseases such as hepatitis, diabetes, or cardiovascular diseases.

OBJECTIVES

  To assess the clinical presentation of TMMA and its association to other systemic diseases, especially the correlation to liver disease, in Taiwan.

METHODS

  We identified and retrospectively analyzed clinical criteria-matched and skin biopsy-proven patients from 2002 to 2010 at a single medical center. The clinical criteria for diagnosis of TMMA included: (i) crops of telangiectasia superimposed on erythematous macules symmetrically on bilateral upper arms, possibly extending to the forearms, shoulders, V-shaped area of the anterior chest, back or thighs; (ii) no mucosal or systemic involvement; (iii) not associated with autoimmune diseases, such as lupus erythematosus, dermatomyositis or systemic scleroderma that may induce cutaneous telangiectasia; and (iv) no ataxia or unsteady gait.

RESULTS

  Twenty-five patients were enrolled in this study. The male-to-female ratio was 19:6. The age of onset was variable, mostly between the third to sixth decades. The V-shaped area of the anterior chest was commonly involved (68%), in addition to the arms (100%). Viral hepatitis was diagnosed in 56.5% of the patients (13/23); 38.9% (7/18) and 50% (9/18) of the patients had diabetes and hypertension, respectively. In addition, 64.7% of the patients (11/17) had dyslipidemia. The pathological reports of most cases showed only mild perivascular lymphocytic infiltration with or without telangiectasia.

CONCLUSIONS

  TMMA should be assigned to a distinct entity with unique clinical manifestation. It has not been well recognized and mostly misdiagnosed as other diseases with telangiectasia. It is important to evaluate the complete liver function tests when TMMA is suspected.

Drosophila Src regulates anisotropic apical surface growth to control epithelial tube size

Networks of epithelial and endothelial tubes are essential for the function of organs such as the lung, kidney and vascular system. The sizes and shapes of these tubes are highly regulated to match their individual functions. Defects in tube size can cause debilitating diseases such as polycystic kidney disease and ischaemia. It is therefore critical to understand how tube dimensions are regulated. Here we identify the tyrosine kinase Src as an instructive regulator of epithelial-tube length in the Drosophila tracheal system. Loss-of-function Src42 mutations shorten tracheal tubes, whereas Src42 overexpression elongates them. Surprisingly, Src42 acts distinctly from known tube-size pathways and regulates both the amount of apical surface growth and, with the conserved formin dDaam, the direction of growth. Quantitative three-dimensional image analysis reveals that Src42- and dDaam-mutant tracheal cells expand more in the circumferential than the axial dimension, resulting in tubes that are shorter in length-but larger in diameter-than wild-type tubes. Thus, Src42 and dDaam control tube dimensions by regulating the direction of anisotropic growth, a mechanism that has not previously been described.

Breast cancer and spider telangiectasias at diagnosis and its relation to histopathology and prognosis: a population-based study

Angiogenesis is one of the hallmarks of breast cancer. The status of angiogenesis is important in therapy choice. Spider telangiectasias (telangiectasias) may reflect an increased ability to form vessels. Our first aim was to identify patient and tumor characteristics associated with the occurrence of telangiectasias at the time of breast cancer diagnosis. The second aim was to study the overall survival in relation to the occurrence of telangiectasias at the time of breast cancer diagnosis. A standardized questionnaire was used to interview 1682 consecutive breast cancer patients about risk factors between 1980 and 2009. Occurrence of telangiectasias at the time of breast cancer diagnosis on the upper thorax, head, and/or neck was recorded by one physician. In the cohort, 93 women (5.5%) had telangiectasias. Occurrence of telangiectasias was positively associated with weight, odds ratio (OR) 1.02 (95% confidence interval (CI) 1.00-1.05) per kg, ever-use of oral contraceptives OR 2.67(CI 1.55-4.63) and hormone replacement therapy OR 2.68(CI 1.63-4.39), and negatively associated with parity OR 0.45(CI 0.25-0.79). Telangiectasias were not present in patients with comedo breast cancer. Patients with occurrences of telangiectasias diagnosed before the age of 50 had a statistically non-significant worse overall survival, whereas the patients with occurrences of telangiectasias diagnosed at age 50 or after had a statistically significant better overall survival (P interaction = 0.016). The relationship between the occurrence of telangiectasias and the overall survival in the older patient-group was independent of ever-use of HRT. Hormonal risk factors for breast cancer were associated with the occurrence of spider telangiectasias. The occurrence of telangiectasias may reflect the angiogenic status of the tumor. We hypothesize that telangiectasias could be used as selection criteria for anti-angiogenic therapy in younger breast cancer patients. Therefore, patients with comedo breast cancers maybe a group that may benefit less from anti-angiogenic therapy.

Down-regulation of mir-424 contributes to the abnormal angiogenesis via MEK1 and cyclin E1 in senile hemangioma: its implications to therapy

Background

Senile hemangioma, so-called cherry angioma, is known as the most common vascular anomalies specifically seen in the aged skin. The pathogenesis of its abnormal angiogenesis is still unclear.

Methodology/Principal Findings

In this study, we found that senile hemangioma consisted of clusters of proliferated small vascular channels in upper dermis, indicating that this tumor is categorized as a vascular tumor. We then investigated the mechanism of endothelial proliferation in senile hemangioma, focusing on microRNA (miRNA). miRNA PCR array analysis revealed the mir-424 level in senile hemangioma was lower than in other vascular anomalies. Protein expression of MEK1 and cyclin E1, the predicted target genes of mir-424, was increased in senile hemangioma compared to normal skin or other anomalies, but their mRNA levels were not. The inhibition of mir-424 in normal human dermal microvascular ECs (HDMECs) using specific inhibitor in vitro resulted in the increase of protein expression of MEK1 or cyclin E1, while mRNA levels were not affected by the inhibitor. Specific inhibitor of mir-424 also induced the cell proliferation of HDMECs significantly, while the cell number was decreased by the transfection of siRNA for MEK1 or cyclin E1.

Conclusions/Significance

Taken together, decreased mir-424 expression and increased levels of MEK1 or cyclin E1 in senile hemangioma may cause abnormal cell proliferation in the tumor. Senile hemangioma may be the good model for cutaneous angiogenesis. Investigation of senile hemangioma and the regulatory mechanisms of angiogenesis by miRNA in the aged skin may lead to new treatments using miRNA by the transfection into senile hemangioma.