No abstract

Mammalian SWItch/sucrose non fermentable (SWI/SNF) remodeling of chromatin modulates transcription and DNA repair. The Brahma (BRM) catalytic subunit of the SWI/SNF complex is one of two mutually exclusive subunits that provide energy for remodeling. BRM has been identified as an important cancer susceptibility locus; however, to date no mutations have been identified in the BRM gene. We performed genetic analysis of BRM in human non-melanoma skin cancers, precancerous lesions, and normal skin revealing a common nonsynonymous point mutation present in one of ten squamous cell and two of six basal cell carcinoma of the skin. This hotspot was not present in germ-line DNA from the same patients, nor in epithelial precancerous lesions. The observed G:C to T:A transversion is typical of mutations occurring following oxidative damage, such as that caused by UVA radiation. This previously unreported hotspot mutation occurs in a highly conserved region of the BRM gene.

Sweet syndrome is an inflammatory disease characterized by fever and painful erythematous plaques with a dermal neutrophilic infiltrate. It is most common in adults, where it is often parainflammatory or paraneoplastic, but is rare in children. We describe 3 cases of neonatal Sweet syndrome, including 1 patient who had myelodysplastic syndrome and immunodeficiency, the first report of a premalignancy underlying infantile Sweet syndrome. We reviewed the literature on patients presenting with neutrophilic dermatosis in the first 6 months of life. Of 20 cases, 6 had a probable viral etiology, 4 primary immunodeficiencies, 3 neonatal lupus syndrome, 1 gastrointestinal involvement, 1 HIV, and 5 probable genetic cases. Three of these had chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome, caused by mutations in the PSMB8 gene. Most children who presented within the first 6 weeks of life had either a serious underlying condition, such as primary immunodeficiency, or a genetic Sweet syndrome, with 2 fatalities among this latter group. The outcome of postinfective cases was good. Extracutaneous involvement was unusual, whereas postinflammatory scarring and cutis laxa occurred in a minority of patients. In conclusion, Sweet syndrome in the neonatal period often heralds a serious underlying disorder and requires thorough investigation.

Background  Nonmelanoma skin cancer is caused by exposure to ultraviolet radiation within sunlight. Actinic keratoses (AKs) are benign precursor lesions that can develop into invasive squamous cell carcinoma (SCC). Little is known about the molecular events that lead to human skin cancer progression from benign to invasive. Objectives  To determine novel genes that may be involved in skin cancer progression based on data from an initial microarray screen of human skin cancers. Methods  The SWI/SNF chromatin remodelling ATPase subunit BRM was identified as being downregulated in SCC but not AK compared with normal skin in our microarray screen. Therefore reverse transcription-polymerase chain reaction, gene methylation and protein expression was used to study BRM and its alternative ATPase subunit BRG1 in a range of human skin cancers. Results  We found reduced levels of mRNA coding for BRM but not BRG1 in SCC. BRM mRNA levels in AK were similar to those in normal skin. Deregulation of BRM did not result from hypermethylation of CpG regions in the promoter of these genes. Both BRM and BRG1 protein was reduced by about 10-fold in 100% of SCC and basal cell carcinoma, but not in AK specimens examined. Conclusions  BRM protein may be decreased due to low levels of mRNA, while BRG1 protein loss appears to be post-translational. BRM and BRG1 may be novel tumour suppressor genes for human skin cancer. They appear to be involved after development of benign lesions, and are downregulated during progression towards invasion.

Hormonal therapy with either tamoxifen or aromatase inhibitors is commonly used to treat women with breast cancer in both the adjuvant and recurrent disease setting. Cutaneous adverse reactions to these drugs have been rarely reported in the literature. We report an unusual case of urticarial vasculitis following the aromatase inhibitor anastrozole that localised to the unilateral trunk and mastectomy scar, and review the literature on the cutaneous adverse effects of hormonal therapy for breast cancer.