Description
The pathogenesis of acne has been linked to multiple factors such as increased sebum production, inflammation, follicular hyperkeratinization, and the action of Propionibacterium acnes within the follicle. 13-cis Retinoic Acid (13-cis RA, isotretinoin) is the most potent agent in acne treatment. Surprisingly, its mechanism of action in acne is still unknown. Gene expression profiling of skin from 8 patients treated with isotretinoin was performed to gain insights into its mechanism of action. Skin biopsies were obtained from the patients at baseline and at 8 weeks isotretinoin treatment. Gene array expression profiling was conducted using Affymetrix HG-U133A 2.0 arrays in order to examine changes in gene expression as a result of treatment. After treatment, 784 genes were significantly changed: 197 up-regulated and 587 down-regulated. The majority of genes that were up-regulated at 8 weeks encode structural proteins of the extracellular matrix such as collagens, fibulin and fibronectin. The preponderance of genes that were down-regulated at 8 weeks are involved in the metabolism of steroids, cholesterol and fatty acids.