A novel anticancer agent, consisting of a monoclonal antibody linked to a chemotherapy drug, showed substantial antitumor activity in ovarian cancer cell lines and in mice, according to a study published online July 29 in the Journal of the National Cancer Institute.

The agent, known as an immunoconjugate, targets a protein, EphA2, which is overexpressed in many human cancers but is absent or expressed at low levels in normal tissues.

Anil K. Sood, M.D., of The University of Texas M.D. Anderson Cancer Center in Houston, and colleagues tested the immunoconjugate in ovarian cancer cell lines, where it bound to cells with high levels of EphA2 but not to those without the protein. In mice, the EphA2 immunoconjugate inhibited tumor growth by 85% compared with that in mice treated with a control immunoconjugate, a highly statistically significant difference. In cell lines, its antitumor effects were also statistically significantly related to decreased proliferation and increased apoptosis of tumor cells.

Chemotherapy drugs typically affect both tumor and normal tissues, which can result in side effects. The immunoconjugate tested by the in this study allows for highly selective delivery of chemotherapy. “In summary,” the authors write, “the findings herein provide a novel EphA2-targeted immunoconjugate with potent antitumor activity in ovarian carcinoma. Further preclinical and clinical development…appears to be warranted.”

Source:
Steve Graff
Journal of the National Cancer Institute