HOW MIGHT PREGNANCY IMMUNIZE AGAINST BREAST-CANCER

PROBLEM: This study investigated how pregnancy might protect against b reast cancer. METHOD OF STUDY: A critical review of the literature was done. RESULTS/CONCLUSIONS: Support for an active role in pregnancy im munizing against breast cancer comes from case studies demonstrating a reciprocal correlation between pregnancy and breast cancer as well as recent experiments supporting the fetal antigen hypothesis that confi rms the presence of a tumor-specific antigen, MUC1, on both fetal and breast cancer tissues. Multiparous women also generate anti-MUC1 major histocompatibility complex-restricted cytotoxic T cell cytolytic acti vity against MUC1-bearing tumor cell lines. Careful investigation of t he fetal antigen hypothesis and tolerogenic mechanisms may lead to eff ective vaccination protocols against breast cancer and other cancers.