Secreted TNF-α and IL-1 in patients with SS are localized in the same area as extracellular HMGB-1 in the lymphocytic infiltrates, suggesting that HMGB-1, together with TNF-α and IL-1, may constitute a pro-inflammatory loop in SS, promoting persistent glandular inflammation [19]. This evidence concerns the gene HMGB1 and synovial sarcoma.