Hypoxia regulates the production and activity of glucose transporter-1 and indoleamine 2,3-dioxygenase in monocyte-derived endothelial-like cells: possible relevance to infantile haemangioma pathogenesis.

BACKGROUND: Infantile haemangioma (IH) may present as a precursor area of pallor prior to the initial proliferative phase, which implies that the early lesion may be hypoxic. OBJECTIVES: To examine the effect of hypoxia on the expression and activity of two key molecular markers of IH, glucose transporter-1 (GLUT1) and indoleamine 2,3-dioxygenase (IDO). METHODS: IH endothelial cells express both haematopoietic and endothelial cell markers. CD14+ monocyte-derived endothelial-like cells have been employed in the study of IH and is the cell type used in this study. RESULTS: GLUT1 transcript, protein and activity levels were strongly induced by hypoxia and remained elevated following 2 days of normoxic recovery. IDO transcript levels were not affected by hypoxia, although IDO protein level was reduced fivefold and IDO activity >100-fold following 2 days of hypoxia. The protein and activity levels returned to normal following 2 days of normoxic recovery. CONCLUSIONS: The findings link the tissue hypoxia that precedes lesion development and the expression and/or activity of two key IH proteins. The early hypoxic insult may contribute to the elevated GLUT1 levels in IH lesions, while the very low IDO activity during the hypoxic phase may promote activation of immune cells in the lesion, which release cytokines that trigger IDO expression and activity and entry into the proliferative phase. Interestingly, IH lesion development shares some common features with ischaemia-reperfusion injury.

Incontinentia pigmenti case series: clinical spectrum of incontinentia pigmenti in 53 female patients and their relatives.

A retrospective case series of 53 female patients with incontinentia pigmenti (IP) including 28 secondary cases (female relatives of probands) was reviewed and compared with other series in an attempt to estimate more accurately the true disease burden of patients with IP. We found that, while the frequency of the first three cutaneous stages of IP was comparable with previous studies, none of the secondary cases manifested any serious neurological complications but all displayed stage IV pale anhidrotic reticulate lines on their posterior calves. This important clinical feature of IP in secondary cases has previously been under-represented in studies that often involved only paediatric probands. Hence, mildly affected cases of IP are often undiagnosed and under-represented in case series to date, possibly leading to inappropriately high estimates of neurological and eye involvement. With the availability of genetic testing, it is now feasible to confirm the variability of the phenotype and the risk of complications in IP.

Primary leiomyosarcoma of the skin.

Leiomyosarcomas of the skin are frequently misdiagnosed clinically. This tumour however, exhibits typical histological and immunohistochemical features. This collection of seven cases of cutaneous leiomyosarcoma on the trunk and limbs of adults with a mean age of 63 years and a range of 49-78 years demonstrates that the clinical diagnosis in each case, from seven different clinicians, did not include the correct diagnosis. In each case, the special immunohistochemical stains were helpful in making the diagnosis with actin and vimentin being positive and S100 and prekeratin stains being negative.

Cimetidine for mucosal warts in an HIV positive adult.

An HIV-positive adult presented with recalcitrant mucosal warts which failed to respond to therapies including curettage and cautery, cryocautery and oral etretinate. There was an apparent complete resolution of intra- and peri-oral warts with the histamine H2 antagonist, cimetidine.