Research Paper

Genes & Nutrition

, Volume 8, Issue 1, pp 79-90

First online:

The soybean peptide lunasin promotes apoptosis of mammary epithelial cells via induction of tumor suppressor PTEN: similarities and distinct actions from soy isoflavone genistein

  • John Mark P. PabonaAffiliated withPhysiology and Biophysics, University of Arkansas for Medical SciencesArkansas Children’s Nutrition Center
  • , Bhuvanesh DaveAffiliated withArkansas Children’s Nutrition CenterThe Methodist Hospital Research Institute
  • , Ying SuAffiliated withArkansas Children’s Nutrition CenterDana-Farber Cancer Institute, Harvard Medical School
  • , Maria Theresa E. MontalesAffiliated withPhysiology and Biophysics, University of Arkansas for Medical SciencesArkansas Children’s Nutrition Center
  • , Ben O. de LumenAffiliated withUniversity of California Berkeley
  • , Elvira G. de MejiaAffiliated withUniversity of Illinois at Urbana-Champaign
  • , Omar M. RahalAffiliated withArkansas Children’s Nutrition CenterInterdisciplinary Biomedical Sciences, University of Arkansas for Medical Sciences
  • , Rosalia C. M. SimmenAffiliated withPhysiology and Biophysics, University of Arkansas for Medical SciencesArkansas Children’s Nutrition CenterInterdisciplinary Biomedical Sciences, University of Arkansas for Medical Sciences Email author 

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Breast cancer is the leading cause of cancer deaths in women. Diet and lifestyle are major contributing factors to increased breast cancer risk. While mechanisms underlying dietary protection of mammary tumor formation are increasingly elucidated, there remains a dearth of knowledge on the nature and precise actions of specific bioactive components present in foods with purported health effects. The 43-amino acid peptide lunasin (LUN) is found in soybeans, is bioavailable similar to the isoflavone genistein (GEN), and thus may mediate the beneficial effects of soy food consumption. Here, we evaluated whether LUN displays common and distinct actions from those of GEN in non-malignant (mouse HC11) and malignant (human MCF-7) mammary epithelial cells. In MCF-7 cells, LUN up-regulated tumor suppressor phosphatase and tensin homolog deleted in chromosome ten (PTEN) promoter activity, increased PTEN transcript and protein levels and enhanced nuclear PTEN localization, similar to that shown for GEN in mammary epithelial cells. LUN-induced cellular apoptosis, akin to GEN, was mediated by PTEN, but unlike that for GEN, was p53-independent. LUN promoted E-cadherin and β-catenin non-nuclear localization similar to GEN, but unlike GEN, did not influence the proliferative effects of oncogene Wnt1 on HC11 cells. Further, LUN did not recapitulate GEN inhibitory effects on expansion of the cancer stem-like/progenitor population in MCF-7 cells. Results suggest the concerted actions of GEN and LUN on cellular apoptosis for potential mammary tumor preventive effects and highlight whole food consumption rather than intake of specific dietary supplements with limited biological effects for greater health benefits.

Keywords

Lunasin Genistein Soy Apoptosis PTEN Mammary epithelial Breast cancer