Expression Patterns of Programmed Cell Death 4 Protein in Normal Human Skin and Some Representative Skin Lesions

The study investigated the expression of the tumor suppressor protein PDCD4 in human skin and various skin lesions. PDCD4 was primarily found in the suprabasal layers of the epidermis and in specific areas of hair follicles, sebaceous glands, and sweat glands, indicating its role in differentiation. In contrast, PDCD4 expression was reduced in the basal cell layer and in areas with high cell proliferation, such as the bulbar area of hair follicles. The study also found that PDCD4 expression was suppressed in the epidermis overlying adult T-cell lymphoma and in the HaCaT keratinocyte cell line when exposed to certain growth factors. Skin cancers generally showed lower PDCD4 expression compared to normal skin, suggesting that enhancing PDCD4 expression could potentially aid in the prevention or treatment of some skin cancers.