Construction and characterization of OC125 single-chain antibody

Ovarian cancer is the leading cause of death from gynecological cancers in Western countries. Over 70% of the patients present with late stage disease, the five-year survival rate for these patients remains at best of 15-30%. Tumor antigen CA125 expression has been shown to correlate with the clinical course of the disease, and CA125 is currently used as a predictor of clinical recurrence in ovarian cancer and to monitor response to chemotherapy treatment. Previous studies showed that CA125 is a high molecular weight glycoprotein having properties of a mucin-type molecule. The biochemical and molecular nature and the function of this antigen are poorly understood. In this study, we have developed an approach based upon intracellular expression of single-chain antibodies (ScFvs) to achieve selective abrogation of CA125, thus to study the role of CA125 in human ovarian cancer cells. The study shows that a ScFv against the CA125 antigen was constructed, and that the soluble antibodies bind to CA125 protein in ELISA when expressed in E.coli."--Résumé abrégé par UM