Background: Survivin and livin are highly expressed in cancer cells and transformed cells, but show little or no expression in normal differentiated tissues. Human antibody responses to tumor-associated antigens have been detected, but little is known about the response to survivin and livin in breast cancer patients.
Methods: We examined the prevalence of anti-survivin and livin antibodies in breast cancer patients with a specific enzyme-linked immunosorbent assay (ELISA) using recombinant protein.
Results: Using a cutoff value for positivity determined as the mean absorbance +2SD for healthy control samples, sera from 11 of 46 breast cancer patients (23.9%) were positive by the ELISA using recombinant survivin protein. Of 46 samples from the same breast cancer patients, 15 (32.6%) were positive for anti-livin antibodies. In addition, 24 (52.2%) were positive for 1 or both ELISAs using the respective proteins. Intensity of anti-livin antibody responses did not correlate with intensity of anti-survivin responses.
Conclusions: Anti-livin antibodies were detected in sera from breast cancer patients by an anti-livin ELISA using full-length recombinant livin protein. Like survivin, livin may act as a major cancer antigen in breast cancer patients.