tretinoin and Keratosis--Seborrheic

Seborrheic keratosis is one of the most common skin benign tumors in humans with a high occurrence rate of 80%-100% in people > 50 years of age; however, its pathogenesis is still unclear. The standard treatment includes cryotherapy and laser surgery for physically removing lesions. Drug therapy for this condition has not been well established. We aimed to evaluate the use of all-trans retinoic acid (ATRA)-loaded microneedle (MN) patches as a simple, alternative therapeutic option to traditional surgical treatments. This therapeutic strategy was designed to induce the proliferation of basal keratinocytes and accelerate stratum corneum turnover, leading to the lesion falling off the surface of the skin. The MN patch induced epidermal hyperplasia and marked expression of heparin-binding epidermal growth factor-like growth factor mRNA and protein corresponding to ATRA activity in the skin of HR-1 hairless mice. The acceleration of stratum corneum turnover was also observed by the dansyl chloride method. The skin irritation study in mice and safety study in humans support the safety findings of our study. Overall, MN patches can offer an effective and safe means of ATRA delivery into the skin, and the ATRA-loaded MN patch appears to be an effective pharmaceutical product providing a novel therapeutic option for seborrheic keratosis.

Topics: Adult; Animals; Collagen; Cytokines; Dermatologic Agents; Drug Delivery Systems; Female; Heparin-binding EGF-like Growth Factor; Humans; Hyperplasia; Intercellular Signaling Peptides and Proteins; Keratosis, Seborrheic; Male; Mice; Mice, Hairless; Microinjections; Middle Aged; Needles; Receptors, Retinoic Acid; RNA, Messenger; Skin; Skin Irritancy Tests; Transdermal Patch; Tretinoin

Pigmented lesions such as of seborrheic keratosis and senile lentigo, which are commonly seen on skin of people>50years of age, are considered unattractive and disfiguring because of their negative psychological impact. Drug therapy using all-trans retinoic acid (ATRA) is an attractive option for self-treatment at home. We have developed an ATRA-loaded microneedle patch (ATRA-MN) and confirmed the pharmacological effects of ATRA-MN application in mice. Here, we describe a clinical study to evaluate the safety and efficacy of ATRA-MN in subjects with seborrheic keratosis or senile lentigo.. ATRA-MN was applied to the lesion site of each subject for 6h once per week for 4weeks. The skin irritation reaction was scored to assess adverse reactions and blood tests were performed to evaluate the presence of systemic adverse reactions. To assess the treatment effect using ATRA-MN, the desquamation and whitening ability of the investigational skin was observed.. Desquamation of the stratum corneum was observed following four ATRA-MN applications at 1-week intervals, but ATRA-MN applications did not induce severe local or systemic adverse effects.. These results showed that ATRA-MN treatment is promising as a safe and effective therapy for seborrheic keratosis and senile lentigo.

Topics: Aged; Aged, 80 and over; Female; Humans; Keratolytic Agents; Keratosis, Seborrheic; Lentigo; Male; Middle Aged; Needles; Skin; Transdermal Patch; Tretinoin