Presence of human papillomavirus type 6 DNA in the perineal verrucoid lesions of Hailey-Hailey disease

[Acne vulgaris. The role of hormones]

Peripherally active androgens control cellular functions by binding to androgen receptors. Follicular keratinocytes and sebocytes are target cells for androgens, which, directly or indirectly, stimulate keratinocyte proliferation and the volume of sebaceous glands as well as the sebum secretion rate. Acne often begins with the adrenarche, namely with the up- regulation of adrenal synthesis of dehydroepiandrosterone sulfate, a hormone that is upstream to testosterone. The majority of acne patients exhibit normal levels of circulating androgens, while sebaceous glands from acne regions exhibit a stronger sensitivity to androgens than the sebaceous glands from other parts of the body. Hormone-like active lipids, hormones in diet and neuropeptides may also play a role in the development of acne lesions. The target of antiandrogen treatment of the skin is mainly the sebaceous gland and the primary effect is sebostasis.

SOX9 is a key player in ultraviolet B-induced melanocyte differentiation and pigmentation

SOX (SRY type HMG box) proteins are transcription factors that are predominantly known for their roles during development. During melanocyte development from the neural crest, SOX10 regulates microphthalmia-associated transcription factor, which controls a set of genes critical for pigment cell development and pigmentation, including dopachrome tautomerase and tyrosinase. We report here that another SOX factor, SOX9, is expressed by melanocytes in neonatal and adult human skin and is up-regulated by UVB exposure. We demonstrate that this regulation is mediated by cAMP and protein kinase. We also show that agouti signal protein, a secreted factor known to decrease pigmentation, down-regulates SOX9 expression. In adult and neonatal melanocytes, SOX9 regulates microphthalmia-associated transcription factor, dopachrome tautomerase, and tyrosinase promoters, leading to an increase in the expression of these key melanogenic proteins and finally to a stimulation of pigmentation. SOX9 completes the complex and tightly regulated process leading to the production of melanin by acting at a very upstream level. This role of SOX9 in pigmentation emphasizes the poorly understood impact of SOX proteins in adult tissues.

Expression of sex-determining genes in the scalp of men with androgenetic alopecia

BACKGROUND

The regulation of the cutaneous steroidogenesis in patients with androgenetic alopecia remains largely unclear.

OBJECTIVE

The purpose of this study was to quantify the expression of the sex-determining genes in different scalp areas.

METHODS

Paired scalp specimens from frontal and occipital scalp areas of 10 patients were examined by real-time RT-PCR for mRNA expression and of 40 patients (mean age 34.9 years, range 22-58) by Western blotting for protein analysis.

RESULTS

The SOX-9 mRNA was most abundant in the skin, while SF-1 mRNA was sparsely detected. The protein levels of DAX-1, SRY and WT-1 were significantly higher in the bald scalp (p=0.003, 0.004 and 0.03, respectively). Only the SRY expression showed a positive correlation with the baldness severity in Norwood-Hamilton classification (p=0.024). There was no association between patient's age and the protein levels. Immunostaining of SOX-9 was detected in the outer root sheath keratinocytes of hair follicles but not in the dermal papillae.

CONCLUSION

Further study on a larger population, including normal subjects and female patients, is needed to confirm the pathogenic role of sex-determining genes in androgenetic alopecia.