散人先生 ABC : アスピリンが乳ガンを防止する！

　これはちょっと誤解あり。正確には、こう。

NEW YORK (Reuters Health) - Aspirin has been shown to protect against breast cancer, but new research suggests that this effect is limited to cancers that contain hormone receptors.
　Breast cancers can have receptors for two female hormones-estrogen and progesterone. Cancers with these receptors, known as receptor-positive tumors, are stimulated to grow by the corresponding hormone. Tamoxifen, a popular anti-breast cancer drug, works by blocking estrogen from binding to its receptor on breast cancer.