Identification of Differentially Expressed Genes in Actinic Keratosis Samples Treated with Ingenol Mebutate Gel

The study investigated the effects of ingenol mebutate gel on gene expression in actinic keratosis (AK) lesions in 15 immunocompetent patients. After treatment, 60% of patients showed a response, with 40% achieving complete clearance of AK lesions. Microarray analysis identified 128 differentially expressed genes, with a significant number of genes downregulated that are associated with epidermal development, keratinocyte differentiation, and cornification. In patients who responded to treatment, 388 genes were downregulated, many of which were related to epidermal development and immune system pathways. The study also confirmed the downregulation of specific genes using qRT-PCR, supporting the microarray results. The findings suggest that ingenol mebutate gel treatment leads to changes in gene expression that are related to skin development and immune response, and genetic markers were identified that may predict therapeutic response. However, the study had limitations due to the small sample size and limited biopsy material, indicating a need for further research with larger sample sizes to confirm these results.