Cancer metastasis--a multistep process.

Dermatologists are confronted daily with proliferative growths which can reach considerable size, but mean no danger to the patient. Seborrheic keratoses are one example. Other growths, such as basal cell carcinoma, are locally destructive.

Differential protease expression by cutaneous squamous and basal cell carcinomas.

To assess the postulated role of plasminogen activation in tumor invasion, we have investigated the cellular sites of synthesis for urokinase-type (uPA) and tissue-type (tPA) plasminogen activators and their inhibitors (PAI-1 and PAI-2) in two human cutaneous neoplasia that differ in their metastatic potential. The combined use of zymography on tissue sections and in situ hybridization demonstrates that uPA is produced by malignant cells of squamous cell carcinomas (SCC) but not by basal cell carcinomas (BCC), whereas tPA is detected exclusively in nonmalignant dermal tissue. In addition, we show that SCC neoplastic cells simultaneously produce variable amounts of PAI-1, and that PAI-1 production correlates inversely with uPA enzymatic activity.

Anetodermic prurigo nodularis (with Pautrier's neuroma) responsive to arotinoid acid.

A woman had symmetrically distributed pruritic nodules for more than 40 years. Microscopically they were characterized by proliferation of nonmyelinated nerve fibers (Pautrier's neuroma) and a total absence of epidermal involvement. Anetoderma developed at the site of former nodules.

Isotretinoin differs from other synthetic retinoids in its modulation of human cellular retinoic acid binding protein (CRABP).

Isotretinoin differs from acitretin and Ro137410 by its striking sebostatic effect in acne after oral, but not topical, administration. The reason for this is not yet understood. Previous studies indicate that cellular retinoic acid binding protein (CRABP) might be implicated in the action of synthetic retinoids.