Relative paradigms between autoantibodies in lupus and autoantibodies in cancer

Autoantibodies which are reactive with intracellular antigens have been studied extensively in autoimmune rheumatic diseases such as systemic lupus erythematosus (lupus), Sjogren's syndrome, scleroderma, dermatomyositis/polymyositis, and other related diseases [1]. Autoantibodies are being recognized with increasing frequency in other illnesses including type I diabetes [2], the paraneoplastic neurological disease syndromes [3,4], liver diseases [5], bullous skin diseases, inflammatory bowel diseases, thyroid and other endocrinopathies, haematopoietic disorders and many others [6]. Autoantibody to p53 was detected in breast cancer [7] but for a time the main interest was in T cell-mediated autoimmunity [8], until it became evident that humoral immunity was also a prominent response in many different types of cancer [9–11]. In this paper, we will review and discuss the special features of spontaneously occurring autoantibodies and in the case of cancer, how some patients’ immune systems appear to be sensing aberrant cellular mechanisms related to tumorigenesis and reporting these events in the form of the contemporaneous appearance of neo-antibodies. There are some similarities between autoantibodies in lupus (and other autoimmune diseases) and autoantibodies in cancer and there are some differences, but important insights into aetiology, pathogenesis and therapeutic strategies could be gained by careful analysis of the deeper implications of autoimmune responses in both lupus and cancer.