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Beta blockers and breast cancer mortality: a population- based study
Thomas I Barron1, Roisin M Connolly, Linda Sharp
1Trinity College, University of Dublin, Dublin, Ireland. barront@tcd.ie
Summary
Beta blocker propranolol use was associated with reduced breast cancer progression and mortality. This finding supports preclinical data on the role of beta-adrenergic signaling in breast cancer.
Area of Science:
- Oncology
- Pharmacology
- Cardiology
Background:
- Preclinical studies indicate beta-2 adrenergic signaling inhibition hinders breast tumor progression and metastasis.
- Beta-blockers are commonly prescribed cardiovascular medications with potential anti-cancer effects.
Purpose of the Study:
- To investigate the association between beta-blocker use and breast cancer characteristics and mortality.
- To determine if beta-1 selective (atenolol) or non-selective (propranolol) beta-blockers impact breast cancer outcomes.
Main Methods:
- Observational study using linked national cancer registry and prescription data (2001-2006).
- Identified women with invasive breast cancer (Stage I-IV).
- Matched propranolol users (n=70) and atenolol users (n=525) to non-users (n=4,738) based on beta-blocker use in the year prior to diagnosis.
Main Results:
- Propranolol use was linked to significantly lower odds of T4 tumors (OR 0.24) and N2/N3/M1 disease (OR 0.20) at diagnosis.
- Propranolol users had a significantly lower cumulative probability of breast cancer-specific mortality (HR 0.19).
- No significant differences in tumor characteristics or mortality were observed for atenolol users compared to non-users.
Conclusions:
- Human data support preclinical findings that inhibiting beta-2 adrenergic signaling can reduce breast cancer progression.
- Non-selective beta-blocker propranolol shows potential in improving breast cancer outcomes.
- Further research into beta-adrenergic signaling pathways in cancer is warranted.
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