Microbiology and Biotechnology Letters (한국미생물·생명공학회지)

The Korean Society for Microbiology and Biotechnology (한국미생물·생명공학회)
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Meta-Analysis for Effect of Dietary Isoflavones on Breast Density and Hot Flush Suppression

이소플라본의 유방암 항암효능에 대한 메타분석

  • Kwon, So-Jeen (Department of Biology Education, Teachers College, Kyungpook National University) ;
  • Song, Bang-Ho (Department of Biology Education, Teachers College, Kyungpook National University)
  • 권소진 (경북대학교 사범대학 생물교육과) ;
  • 송방호 (경북대학교 사범대학 생물교육과)
  • Received : 2011.07.01
  • Accepted : 2011.07.26
  • Published : 2011.09.28
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Abstract

For establishing the efficacy against breast cancer occurrence, women's mammographic breast density and hot flush remission related to pre and post-menopausal symptoms were selected as biomarkers. Meta analysis applied the final selection of 40 papers from Medline to assess the efficacy of isoflavone-rich soy or supplements versus placebo under randomized controlled trials. Interestingly, the exposure to the purified isoflavones was more effective than the exposure to the crude extract of soy isoflavones for hot flush suppression. The length and the amount of dosage dependency is the most appropriately suggested to be one year long with 50~100 mg/day of isoflavone-rich soy or supplements. Funnel plots was used to interpret the results, overall effect of isoflavones on breast density in post-menopausal women was revealed to be less effect [effect size: 0.062, 95% confidence interval (CI): 0.005 to 0.12], than that of pre-menopausal women (effect size: 0.101, CI: -0.003 to 0.205). The reason why breast density was found higher among the pre-menopausal than the post-menopausal women is that the phytoestrogens of dietary isoflavones were antagonized against estrogen by the basis of estrogen receptor binding affinity. Overall, the Meta analysis reported that isoflavone had limited influence on breast density by suppressing the expansion by only 2%, while it was more effective to suppressing the hot flush, showing a dramatic decrease of 23%.

대두 이소플라본 성분의 유방암 항암성과 다양한 폐경기 증상의 완화 효능을 분석하고자 유방밀도와 안면홍조현상의 억제능을 생체 마커로 설정하였다. 중재 유형으로 대두, 적클로버, 승마 등에서 정제된 이소플라본과 대두의 조추출액을 설정하여 지난 15년간의 관련 논문을 색인, 40여 편의 중재논문을 선별하였다. 이소플라본의 효과는 유방영역, 밀집, 비밀집 영역, 홍조의 심화도, 발생 빈도, 혈관질환성 등을 종속변수로 설정, 복용량, 복용기간, 복용시기, 폐경 여부 등의 요인에 따른 항암 효과를 비교분석하였다. 그 결과 중재유형별로 유방밀도와 안면홍조의 억제효능에서 전자는 대두 추출물에서, 후자는 정제된 이소플라본에서 현저하게 강한 효능이 나타났다. 종속변수로써 유방밀도는 밀집영역과 음영백분율에서는 양성적 효능이 인정되었고, 안면홍조에서는 홍조의 심화도에 비해 발생빈도가 현저히 억제되었다. 유방 밀도와 안면홍조에 강한 억제 효능이, 복용량에서는 50 mg/일 이상 100 mg/일 미만, 복용기간은 1년 정도가 가장 효율성이 높은 노출기간으로 판정되었다. 특히 폐경 전이 폐경후보다 유방밀도와 안면홍조의 억제효과가 더 강하게 나타났다. 이상의 결과 포괄적인 메타분석에서 유방밀도는 이소플라본에 의해 2%가 억제되어 효능이 약하였지만 안면홍조는 23%의 강한 억제효능이 있는 것으로 해석되었다.

Keywords

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