Anti-tumor and anti-ovarian autoantibodies in women with ovarian cancer.

PROBLEM There is a lack of validated marker(s) for the diagnosis of early-stage ovarian cancer (OVCA). The objective was to determine if women with OVCA had antibodies, to assess their potential as markers of ovarian cancer. The secondary objective was to compare the prevalence of antibodies to proteins from normal ovary and ovarian tumors to determine if antibodies primarily recognize tumor antigens, as many antigens are common to tumor and normal ovary. METHOD OF STUDY Serum samples from patients with OVCA, borderline or benign ovarian tumors, endometrial cancer and healthy women were examined for anti-ovarian and anti-tumor antibodies by immunoassay. Immunoreactive proteins were characterized by one- and two-dimensional Western blot. RESULTS Ovarian (81%, P < or = 0.001) and anti-tumor (69%, P < or = 0.001) autoantibodies in OVCA were significantly different from those of control sera. A majority of OVCA serum samples reacted with proteins at about 50 kDa from normal ovary or ovarian tumors in one-dimensional Western blot. While there were similar reactions in two-dimensional Western blots, there are differences between reactions to normal and tumor antigens and between reactions to autologous and allogeneic tumors. CONCLUSION Serum autoantibodies are significantly associated with OVCA. Anti-tumor antibodies may provide a useful marker for the detection of ovarian cancer.