Mucin1 expression in focal epidermal dysplasia of actinic keratosis

Treatment of actinic keratosis through inhibition of cyclooxygenase-2: Potential mechanism of action of diclofenac sodium 3% in hyaluronic acid 2.5

Cyclooxygenase‐2 (COX‐2) and its metabolic product prostaglandin E₂ (PGE₂) are induced in response to growth factors, inflammatory cytokines, tumor promoters, activated oncogenes, and, in the skin, ultraviolet (UV) radiation. Accumulating evidence suggests a role for the COX‐2/PGE₂ pathway in tumorigenesis in various tissue types including cutaneous squamous cell carcinoma. There is also strong evidence for a role in the development of actinic keratoses (AKs) — common dysplastic lesions of the skin associated with UV radiation overexposure — considered as part of a continuum with skin cancer. Non‐steroidal anti‐inflammatory drugs (NSAIDs) exert their anti‐inflammatory, analgesic, and antipyretic effects by reversibly or irreversibly acetylating COX isoforms, inhibiting downstream prostaglandins, and may have a chemopreventive role in malignancies, including skin cancer. Topical treatment of AK lesions with the NSAID diclofenac sodium 3% in combination with hyaluronic acid 2.5% has been shown to be effective and well tolerated, although the mechanism of action remains to be elucidated.

CD44 Immunoexpression in the Progression of Actinic Keratosis and Cutaneous Squamouscarcinoma

CD44 seems to confer the needed conditions for malignant neoplasms to grow and progress. The present study aims to investigate the role of CD44 expression in pre-invasive and invasive squamous lesions of the skin. We investigated 89 cases of preinvasive and invasive cutaneous lesions, of which 28 corresponded to actinic keratosis (KIN- keratinocyte intraepithelial neoplasia) with varying degrees of severity and 61 cases of squamous cell carcinoma with variable degrees of differentiation. The statistical analysis of CD44 immunoexpression indicated significantly higher values for KIN I and II compared to KIN III, as well as for KIN lesions in comparison with squamous cell carcinomas. Similar results were observed in well differentiated carcinomas compared to moderate and poorly differentiated lesions. These observations suggest that CD44 expression plays a role in the progression of cutaneous squamous neoplasia.