Digoxin use and the risk of breast cancer in women.
ABSTRACT Digoxin resembles estrogen chemically and may have estrogenic effect. We hypothesized that digoxin use might increase breast cancer incidence and examined if use might be associated with risk of breast cancer, categorized by estrogen receptor (ER) status. To determine if being under care for heart disease biased the findings, rate ratios in users of angina drugs were similarly evaluated as a control exposure group.
Women using digoxin and angina drugs were identified in the nationwide Danish Prescription Database, available between 1995 and 2008. Incident breast cancers were identified in the Danish Cancer Registry and further classifying by ER status. Relative risks (RR) were compared to nonusers using age- and period-adjusted incidence rate ratios.
Two thousand one hundred forty-four of 104,648 women using digoxin developed breast cancer. Current digoxin users were at increased risk of breast cancer (RR, 1.39; 95% CI, 1.32 to 1.46), but risk was not increased in former users (RR, 0.91; 95% CI, 0.83 to 1.00). The increased risks in digoxin users were marginally higher for ER-positive breast cancers (RR, 1.35; 95% CI, 1.26 to 1.45) and ER unknown breast cancers (RR, 1.51; 95% CI, 1.38 to 1.64) than for ER-negative breast cancers (RR, 1.20; 95% CI, 1.03 to 1.40). Among 137,493 women exposed to angina drugs only (a comparison group with cardiovascular disease; n = 2,658 breast cancers), incidence was not increased in current or former users.
Women currently using digoxin had a significantly increased risk of breast cancer. Risk normalized when digoxin was stopped. No risk increases were observed in women using angina drugs only. The higher risk of developing ER-positive breast cancers supports an estrogen-mimicking mechanism.
[show abstract] [hide abstract]
ABSTRACT: Some successful chemotherapeutics, notably anthracyclines and oxaliplatin, induce a type of cell stress and death that is immunogenic, hence converting the patient's dying cancer cells into a vaccine that stimulates antitumor immune responses. By means of a fluorescence microscopy platform that allows for the automated detection of the biochemical hallmarks of such a peculiar cell death modality, we identified cardiac glycosides (CGs) as exceptionally efficient inducers of immunogenic cell death, an effect that was associated with the inhibition of the plasma membrane Na(+)- and K(+)-dependent adenosine triphosphatase (Na(+)/K(+)-ATPase). CGs exacerbated the antineoplastic effects of DNA-damaging agents in immunocompetent but not immunodeficient mice. Moreover, cancer cells succumbing to a combination of chemotherapy plus CGs could vaccinate syngeneic mice against a subsequent challenge with living cells of the same type. Finally, retrospective clinical analyses revealed that the administration of the CG digoxin during chemotherapy had a positive impact on overall survival in cohorts of breast, colorectal, head and neck, and hepatocellular carcinoma patients, especially when they were treated with agents other than anthracyclines and oxaliplatin.Science translational medicine 07/2012; 4(143):143ra99. · 7.80 Impact Factor