Potential Target for Treating Psoriasis Found

The key to stopping the skin disease psoriasis (search) may be a molecule called Stat3 —a potential new target for psoriasis treatment.

Stat3 is found in most human skin cells that make up psoriasis patches, say scientists including Shigetoshi Sano of the University of Texas M.D. Anderson Cancer Center in Houston. Sano’s team also found Stat3 in psoriasis patches on mice bred to have a psoriasis-like disorder.

In their mouse study, Sano’s team found that blocking Stat3’s function slows the onset of psoriasis patches and heals the patches, too.

Reporting their findings in the online edition of the journal Nature Medicine, the researchers say they don’t know exactly how Stat3 exerts its influence. Still, they think future psoriasis treatments focused on Stat3 might work.

Psoriasis is one of the most common inflammatory skin conditions, affecting about 2% of people in western countries. It usually affects adults, but kids and teens can get it, too. Psoriasis causes patches of itchy, scaly, and sometimes inflamed skin.

Although they can appear anywhere, these patches are most likely to crop up on your knees, elbows, hands, feet, scalp or back.

The symptoms of psoriasis can vary a great deal depending on its severity, ranging from mildly annoying to truly debilitating.

Its cause is unknown. Sano and colleagues say it’s not clear if the problem is caused by abnormal skin cells or immune system problems, although both may be factors. There is no cure for psoriasis, although various treatments are available.

Stat3 has also gotten attention for other skin-related conditions. It’s essential for healing skin wounds, says Sano’s team.

In September, other researchers announced that lab tests on mice show that the gene that makes Stat3 may play a role in skin cancer. The gene may also be related to cancers of the prostate, breast, lung, head and neck, brain, and pancreas, according to that report.

By Miranda Hitti, reviewed by Michael W. Smith, MD

SOURCES: Sano, S. Nature Medicine, advanced online publication, Dec. 12, 2004. WebMD Medical Reference from Healthwise: “Psoriasis: Topic Overview.” WebMD Medical Reference from Healthwise: “Psoriasis: Treatment Overview.” WebMD News: "Gene Tied to Growth of Skin Cancer.” News release, Nature.