[Correlation between the effect of chemotherapy on complement conformation and on CA-125 antigen in the blood plasma of patients with ovarian carcinoma].

Correlation was investigated between blood-plasma levels of C3(H2)O (conformation pattern of C3 component of the complement) and tumor-associated marker CA-125 in patients with ovarian cancer before and after chemotherapy. Since a drop in CA-125 level after chemotherapy was associated with similar changes in C3(H2)O fraction, it seems reasonable to suggest that change in conformation of C3 is a response of the immune system to cancer.