Study: Cancer may trigger scleroderma

Results of a Johns Hopkins study suggest that cancer triggers the autoimmune disease scleroderma.

Patients with scleroderma often make immune proteins or antibodies to another protein, RPC1, according to a news release. These antibodies are believed to cause the organ damage characteristic of scleroderma, though it’s not known what causes the production of these antibodies.

Using blood and tumor tissue samples from 16 patients with scleroderma and different kinds of cancer, the research team found that cancers from most patients with severe scleroderma had a mutation in the gene POLR3A, which codes for RPC1. These alterations created a “foreign” form of the RPC1 protein, which the researchers say appears to trigger an immune response.

“The most significant finding is that specific mutations in autoantigens in cancer initiate the immune response in a subset of scleroderma patients, suggesting that cancer is an initiator of scleroderma in some patients,” study investigator Antony Rosen, M.D., tells Dermatology Times. “This may have broader implications for other autoimmune diseases, and for understanding the role of the immune system in controlling cancer.”

Dr. Rosen, vice dean for research at Johns Hopkins University School of Medicine, says the team’s findings should spur research into the possible cancerous origins of other autoimmune diseases, including lupus and myositis, and whether immune responses to antigens other than RPC1 are involved.

The study was published online Dec. 5 in Science.