Some Scleroderma Patients are Protected from Cancer

Some scleroderma patients carry enriched antibodies that may prevent cancer and provide immunity to other systemic sclerosis-associated conditions, such as scleroderma renal crisis and SSc-gastrointestinal disease. (©PhuShutter,Shutterstock.com)

Researchers writing in Arthritis and Rheumatology have found that some scleroderma patients carry enriched antibodies that may prevent cancer and provide immunity to other systemic sclerosis-associated conditions, such as scleroderma renal crisis and SSc-gastrointestinal disease.

The development of cancer is more prevalent in scleroderma patients than the general population, but it has a 2.8 times higher risk in a subset of patients with anti‐RNA polymerase III large subunit (anti‐RPC155) antibodies. Of these, 85 percent of patients do not develop cancer. This suggests that cancer might be a trigger for an autoimmune response in the presence of scleroderma that halts the cancer or prevents it from emerging.

To test this theory, Shah and colleagues evaluated serum antibodies from 168 patients who were anti-RPC-155 positive. Nearly half (80 patients) had a history of cancer, while the remaining 88 did not. Another band, 194 kDa, of the polymerase I subunit (RPA 194) was also detected in nearly 40 percent of the SSc patients with cancer, compared to only 6 percent of those without.

THE FINDINGS

(1) Anti-RPA194 antibodies were significantly more common in the group without cancer (16/88, 18.2%) than the group with cancer (3/80, 3.8%; p=0.003).
(2) Patients with anti-RPA194 and anti-RPC155 were significantly less likely to have severe gastrointestinal disease (26.3% vs 51.0%, p=0.043) than patients with only anti-RPC155.

The authors concluded that the subgroup of patients with both RPC 155 and RPA 194 antibodies was protected from cancer.

REFERENCE

Shah AA, Laiho M, Rosen A, Casciola-Rosen L. “Scleroderma patients with antibodies against the large subunits of both RNA polymerases-I and -III are protected against cancer.” Arthritis and Rheumatology. 2019 Mar 19. DOI: 10.1002/art.40893. [Epub ahead of print]