Unilesional mycosis fungoides is associated with increased expression of microRNA-17~92 and T helper 1 skewing.

Background: The molecular basis of unilesional mycosis fungoides (MF), characterized by a solitary lesion that is clinicopathologically indistinguishable from multifocal patch or plaque MF (early MF), is unknown.

Objectives: To investigate the microRNA profile in unilesional MF distinguishing it from early MF.

Methods: Biopsy samples of unilesional MF and early MF were evaluated with the Affymetrix microRNA array, with further comparison with inflammatory dermatosis, using quantitative polymerase chain reaction.

Vitamin D Induces Cyclooxygenase 2 Dependent Prostaglandin E2 Synthesis in HaCaT Keratinocytes.

The active metabolite of vitamin D calcitriol and its analogs are well-known for their anti-inflammatory action in the skin, while their main side effect associated with topical treatment of inflammatory disorders is irritant contact dermatitis. Prostaglandin E2 (PGE2 ) is pro-inflammatory at the onset of inflammation and anti-inflammatory at its resolution. We hypothesized that induction of PGE2 synthesis by calcitriol in epidermal keratinocytes may contribute both to its pro-inflammatory and anti-inflammatory effects on the skin.

Vitamin D inhibits captopril-induced cell detachment and apoptosis in keratinocytes.

Background: Captopril, an angiotensin I-converting enzyme inhibitor, is a commonly prescribed antihypertensive drug. Its cutaneous side-effects include pemphigus vulgaris acantholysis and bullous pemphigoid-like cell-matrix detachment. This medication also triggers apoptosis in human keratinocytes.

Vitamin D protects keratinocytes from deleterious effects of ionizing radiation.

Background: Radiotherapy can induce severe skin responses that may limit the clinically acceptable radiation dose. The responses include erythema, dry and moist desquamation, erosions and dermal-epidermal blister formation. These effects reflect injury to, and reproductive failure of, epidermal cells and may also be due to dysregulation of the tissue remodelling process caused by excessive proteolytic activity.

Two modes of ERK activation by TNF in keratinocytes: different cellular outcomes and bi-directional modulation by vitamin D.

Inflammation, elicited in the skin following tissue damage or pathogen invasion, may become chronic with deleterious consequences. Tumor necrosis factor (TNF) is a key mediator of cutaneous inflammation and the keratinocyte an important protagonist of skin immunity. Calcitriol, the hormonally active vitamin D metabolite, and its analogs attenuate epidermal inflammation and inhibit the hyperproliferation of keratinocytes associated with the inflammatory disorder, psoriasis.