Immuno-hormonal network in postmenopausal women: disturbance in breast cancer patients

Antibodies to estradiol and progesterone (Es and Pg) modulated their blood serum concentration and biological effects in immunized animals. Antibodies to membrane steroid receptors acted as hormone agonists or antagonists in cell cultures.

Here we studied the levels of Es and Pg, idiotypic immunoglobulin (Ig) A1 and anti-idiotypic IgG2 specific to Es and Pg in the serum of postmenopausal women (82 healthy donors and 443 breast cancer patients).

It was found that individual high ratios of Pg/Es (> 4), IgA-Pg1/IgA-Es1 (> 1) and IgG-Pg2/IgG-Es2 (> 1) were associated with low breast cancer risk (OR = 0.4-0.5). High ratios of IgA-Pg1/IgA-Es1 and IgG-Pg2/IgG-Es2 were associated with a high Pg/Es ratio in healthy women but not in breast cancer patients. The levels of idiotypic IgA to benzo[a]pyrene correlated significantly with IgA-Es1 and IgA-Pg1 levels in both compared groups. IgA-Pg1/IgA-Es1 ratio correlated with IgG-Pg2/IgG-Es2 only in healthy women but not in breast cancer patients.

The normal immune-hormonal balance supports the real adaptation of the organism to environmental carcinogens and inhibits the initiation and promotion of carcinogenesis. The disturbance between certain elements of this network (immune-hormonal disbalance) could stimulate carcinogenesis. Further studies of immune-hormonal interaction could be helpful for understanding the pathogenesis of other carcinogen-induced steroid-dependent diseases in humans.